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31ENGINEERING INTEGRITY EIS

September 2011

J O U R N A L O F T H E E N G I N EER I N G I N TE G R I T Y S O C I ET Y

paper on: •

The Telescopic Cantilever Beam: Part 2 - Stress Analysis

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Contents Instrumentation, Analysis & Testing Exhibition 2012 .......................................................................................................... 1 Index to Advertisements ...................................................................................................................................................... 2 Editorial ................................................................................................................................................................................ 5 Technical Paper: The Telescopic Cantilever Beam: Part 2 – Stress Analysis .................................................................. 6 Technical Article: Mechanical Testing of Micro Specimens and Semi-finished Micro Products ..................................... 18 Report on EIS Forum “Seven posters - is that three too many?” ..................................................................................... 23 Corporate Sponsor Application Form ................................................................................................................................ 23 Industry News .................................................................................................................................................................... 24 Product News .................................................................................................................................................................... 28 Personal Membership Application Form .......................................................................................................................... 30 Profiles of Company Members ......................................................................................................................................... 31 News on Smart Materials and Structures ......................................................................................................................... 32 News from Formula Student ............................................................................................................................................. 33 Diary of Event ..................................................................................................................................................................... 33 Challenge to Improve the Process from design to product ............................................................................................. 34 News from British Standards ............................................................................................................................................ 35 “Open Access”, another instalment .................................................................................................................................. 36 Group News ...................................................................................................................................................................... 37 Committee Members ........................................................................................................................................................ 38 Sponsor Companies ......................................................................................................................................................... 39

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Editorial Welcome to the 31st edition of the EIS

graduates are joining their psychology colleagues

journal. With hurricanes blowing away

behind the counters of fast food restaurants. The authors

the last vestiges of summer we have a

of the study note the contrast between their findings and

bumper edition for you, containing two

the experience of employers in the sector, suggesting

papers and an extended range of news

that the shortage is really one of quality STEM graduates.

sections, including the new ‘product

Perhaps the private sector has yet to accept that education

news’ giving industry the opportunity to

standards are constantly improving!

announce key technology releases. With the new University tuition fee regime starting next The first paper, ‘the telescopic cantilever beam: Part 2’

year this has been a bumper year for recruitment in many

describes the stress analysis performed for a telescopic

institutions. The past couple of years of ‘plenty’ have

cantilever beam and follows from Part I published in the

allowed entry requirements to be raised, but whether or

last edition. The second paper, ‘Mechanical testing of

not the actual quality of the intake has improved remains

micro specimens and semi finished micro products’

to be seen. The over emphasis on rote learning at A-

provides user experience of test frame design specifically

level leaves many students, not just the weaker ones,

for the purpose of small scale testing. Something close

struggling to genuinely understand material, let alone

to our interests at Swansea, we are often asked to assess

analyse a problem they haven’t been given a model

a new material capability based on minimal material

answer for. In the new market lead system the student

availability before a full scale melt is produced.

will be king and University administrators will be straining

Development of new alloys often starts with the

every sinew to improve their student satisfaction ratings.

manufacture of small buttons of experimental alloy and

In this environment it is a brave or foolish lecturer who

a preliminary mechanical assessment is required from

denies the customer the spoon feeding they crave. At

a quantity of material more commonly utilized for a single

least employability will also be a headline key

mechanical test. The development of tests techniques

performance indicator.

for gaining a range of mechanical properties from minimal material represents a technological challenge.

Finally, the group events are proving extremely popular; with attendance at a record high. It is encouraging to see

Smart materials also hit on a pertinent point with regards

that many attendees were from the young engineers keen

to new exotic materials. Many advanced alloys nowadays

to advertise their work.

consist of the rare earth elements that offer improvements in temperature and mechanical capability. Future

Karen Perkins

availability and access to these elements is paramount

Honorary Editor

and forms a key part of new alloy development. The Industry news section again provides an interesting mix of topics with a range of green issues, robotics featuring in several guises and the application of phasechange materials in the development of ‘brain-like’ computers. Perhaps these computers will develop more understanding than the two chatbots who made the national news recently when their conversation rapidly descended into an argument. Despite our perennial concerns about the shortage of engineering

graduates,

recent

research

from

Birmingham University suggests that many engineering

5


ENGINEERING INTEGRITY, VOLUME 31, SEPTEMBER 2011 pp.6-17.

ISSN 1365-4101/2011

Technical Paper The Telescopic Cantilever Beam: Part 2 – Stress Analysis J. Abraham, D. W. A. Rees and S. Sivaloganathan, School of Engineering and Design, Brunel University, Uxbridge, Middlesex, UB8 3PH Abstract This paper is an extension to a Part 1 analysis of the deflection for a telescopic cantilever beam [1]. The Tip Reaction Model, proposed in that paper, establishes reactions at the tips of the overlapping portions as the mechanism of transfer of the external loads between sections of the telescopic beam. In Part 1 a three-section telescopic beam was analysed for deflection using these forces within a repeated integration method. In Part 2 the bending and shear stresses for the three-section cantilever, are obtained both analytically and numerically. A check upon stress levels is provided from a parallel study upon an equivalent, two-stepped, continuous beam. Graphical presentations of the beam stresses, found from applying the two methods to each structure, are self-validating. That is, the continuous beam theory provides a check upon numerical stress levels from FEA and, in turn, FEA provides a check upon the analytical stresses calculated from tip reactions within a telescopic beam. The fact that comparable stress levels were found confirms that the analytical technique proposed is perfectly adequate for a telescoping beam, just as the classical theory is adequate for continuous beams. Taken together, Parts 1 and 2 provide an analytical theory for bending of a discontinuous beam that did not exist heretofore, thereby obviating the need for a numerical solution.

To understand how the material in the beam resists the external loads it is seen that the beam sags beneath the applied loads. Sagging creates a compressive stress within longitudinal fibres lying in the upper half of the section and tensile stress within fibres in the bottom half. A neutral (unstressed) plane MN divides each half as shown in Figure 1. The equivalent compressive force acting on the upper area MEFN is given by ‘C’. Similarly the equivalent tensile force acting on the lower area MHGN is given by ‘T’. The external loads applied and the effective shear force S acting on the plane EFGH are assumed to be concentrated on the vertical plane of symmetry, as shown. The forces that act over length AX of the beam are therefore: (a) a vertical reaction RA at A, (b) external concentrated loads W1 and W2, (c) uniformly distributed load w acting over the length x , (d) shear force S offered by section EFGH, (d) a compressive resistance C and (e) a tensile resistance T. The magnitudes of the forces C and T are equal and, since they act in opposing directions, separated by a distance d, they form the section’s moment of resistance:

MR = Cd = Td

Taking moments about O gives the bending moment due to the external forces

(2)

1.0 Introduction Continuous structures balance the application of external loads with an internal resistance within their material which is commonly called stress. For a beam in particular, resisting moments arise from its internal stress to oppose the bending moments that the transverse loading produces. For example, consider the simply-supported beam with selfweight w/unit length subjected to four concentrated loads W1 ... W4 shown in Figure 1.

(1)

In continuous beams we may equate (1) and (2) when applying the principle that the moment at a given section due to externally applied loads equals the moment of resistance at that section. However, the same principle cannot be applied to telescopic beams within the discontinuous region between overlapping sections, especially where there is a sizeable gap between them. To overcome this the authors proposed [1] their Tip Reaction Model, the principle of which is summarised in the following section. 1.1 Tip Reactions

Figure 1: Moment of resistance within section at x-position

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The tip reaction model assumes that in a telescopic cantilever beam the overlapping ends have concentrated reactions that transmit the effects of the loads applied to the top surface of the cantilever assembly. Consider the threesection beam assembly shown in Figure 2. The fixed beam AB has an overlap of length CB with beam CD. The outer beam EF also has an overlap of length ED with beam CD. Tip reactions exist at the contact points C and B between


ENGINEERING INTEGRITY, VOLUME 31, SEPTEMBER 2011 pp.6-17.

along each length are converted to their respective stresses in the following section. The stress magnitudes are compared with those obtained from a finite element analysis. The analyses were carried out on a telescopic cantilever assembly consisting of three hollow sections the details of which follow. Comparable stress levels were anticipated from a further validation which compares magnitudes between the ‘moment of resistance’ theory and FEA for a continuous stepped-beam of similar dimensions and loading. 1.2 Bending Stress Figure 2: Telescopic beam assembly with three sections

beams AB and CD. Similarly, tip reactions exist at the overlapping ends E and D between beams CD and EF. In addition, Fig. 3a shows the external loading applied to the assembly which is a combination of self-weight and a concentrated end-load. Thus, each of the three-sections bears the loading shown in Figures 3b-d.

The longitudinal bending stress in a beam is calculated from the bending moment M by a standard expression [2]:

σ=

M y I

(3)

where I is second moment of area of the beam section and y is the distance from the neutral axis at which this stress applies. Consider the beam assembly shown in Figure 2 and assume that it is fixed at end A and carries a tip load at F. Due to self-weight and the tip loading applied there will be tensile stresses in all three beam sections above the horizontal of symmetry (neutral plane) and compressive stresses below the plane of symmetry. For each section depth: d 1 , d 2 and d 3 , the beam is represented by the vertical plane of symmetry upon which the maximum bending stress occurs at their top surfaces. These are found from Eq. (3) as:

σ1 =

M × d1 M ×d2 , σ2 = 2I 1 2I 2

and

σ3 =

M × d3 2I 3 (4a-c)

Figure 3: Telescopic assembly showing tip reactions within individual beams In Figs 3b-d each beam section is shown separately as a free-body diagram. Within each diagram the tip reactions are the forces applied to each section from its neighbour. Thus, the end-section exerts upon the middle section a downward force at D and an upward force at E (see Fig. 3c). The middle-section exerts equal forces upon the endsection at D and E but in opposition to these (see Fig. 3d). That the tip reactions must remain in equilibrium with the applied loading enables these reactions to be found [1]. Consequently, the internal shear force and moment within each length may be calculated from the reactions instead of the moment of resistance used normally for a continuous beam. The shear force and bending moment variations

The d- and I-values are referred to a chosen geometry given in the following section. The bending moment M in Eqs 4a-c varies within the length in a manner provided by an M-diagram constructed from the applied loading and the tip reactions. 1.3 Shear Stress

Figure 4: Shear stress parameters at depth position y1 for section x-x

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ENGINEERING INTEGRITY, VOLUME 31, SEPTEMBER 2011 pp.6-17.

Consider the uniform cantilever shown in Figure 4. Let a transverse shear force S apply vertically along the section X-X at a distance x from the fixed-end. It is required to find the shear stress within section X-X at a distance y1 (at EF) from the neutral axis as shown. The area above EF is a and the distance from the centroid of this area to the neutral axis is y. Given a uniform breadth b for the cross-section, the transverse shear stress at the required position is found from [2]:

(5)

CD and EF have an overlap of 300 mm. The second moment of area about the neutral axis for the cross-section of beams AB, CD and EF are 9232 mm4 6188 mm4 and 3900 mm4 respectively. Their linear densities (distributed self-weights) are 0.007536 N/mm 0.006594 N/mm and 0.005652 N/mm respectively. 2.2 Area Properties Consider the hollow, square rectangular section shown in Figure 5. The outer side depth is d and thickness is t for which the following relationships apply

Equations (3) - (5) may be applied to both telescopic and continuous beams when M and S are known. In what follows M and S are converted to their respective stress distributions from within the diagrams that show the variations in M and S over the length. The method of constructing S- and Mdiagrams for continuous cantilever beams, carrying combined concentrated and distributed loading, can be found in many texts [2-5]. The F- and M-diagrams for a telescopic beam may be constructed separately once the tip reactions for each of Figs 3b-d are known (see Part 1 [1]) and then superimposed to find their net values within the overlaps.

Figure 5: Hollow, square tubular section

Cross sectional area: 2.0 Case Study Formulation

A = (d 2 - (d - 2t)2) = 4t(d - t)mm2

The following three investigations have been made

Volume of a section, 1 mm long:

i. To calculate the bending and shear stresses from the tip reactions in a telescopic cantilever and compare these with the results of a Finite Element Analysis (ABAQUS). ii. To calculate the bending and shear stresses for a comparable, single-stepped cantilever and compare these with a Finite Element Analysis. iii. To compare the stresses between the telescopic and continuous cantilevers as provided by the analyses in (i) and (ii).

V / L = A = 4t(d - t) = 4t(d - t)mm3 / mm

Note that for (i) – (iii), the continuous cantilever, being a simpler structure to solve, offers greater certainty that realistic, agreeable stress levels will be provided by each technique.

Self-weight (density) of 1mm3 of steel (taking g = 10 m/s2)

Self-weights of 1 mm long beam sections (distributed loads)

× (7.85 × 10 −5 ) Nmm −3 = 3.14t ( d − t ) × 10 −4 N / mm (4) Second moments of area for a hollow square section

2.1 Model Geometry The model telescopic cantilever beam assembly consists of three hollow square steel sections, each 1 mm thick, with outer dimensions: 25mm x 25 mm x 1000 mm, 22 mm x 22 mm x 1200 mm and 19 mm x 19 mm x 1200 mm. A load of 30 N is applied at the end of the beam assembly. Beam CD and AB have an overlap of 400 mm and beams

8

I =

(d

4

− ( d − 2t ) 4 12

)

(5)

Equations (4) and (5) provide the I- and w -values for the section dimensions d and t given in Table 1.


ENGINEERING INTEGRITY, VOLUME 31, SEPTEMBER 2011 pp.6-17.

Table 1: Tubular square-section properties

3.0 Finite Element Analyses Two separate finite element analyses were conducted. The first applies to the assembled telescopic cantilever carrying a tip load of 30 N. The second applies to the single, stepped cantilever with comparable section dimensions under a similar load. 3.1 Telescopic Beam Assembly for FEA

Figure 6: Telescope beam assembly for FEA

Table 2: FEA (ABAQUS) for the telescopic beam assembly

In practice, telescopic beam sections slide upon and react their loading through these wear pads. Hence, four wear pads are introduced to make the FE analysis correspond with the analytical approach. Wear pad 1, of 0.5 mm thickness and 5 mm wide, is glued the inside of the free-end of beam 1 as shown in Figure 6. Similarly, wear pad 2, of similar dimension, is glued to the outside end of beam 2. Wear pad 3 is glued to the inner end of beam 2 and wear pad 4 is glued to outside end of beam 3, as shown. 3.2 Finite Element Analysis for the Assembly With the details of the telescopic beam assembly model provided in 3.1, Table 2 shows the finite element analysis procedure adopted by ABAQUS. The left-hand side shows the flow chart and the right-hand side gives the detail. 3.3 Finite Element Analysis of SingleStepped Beam Normally telescopic beam sections have a 1mm gap between sections to facilitate easy sliding. This clearance needs to be allowed for within an equivalent, continuous steppedcantilever. In Fig. 7, the end view 1 shows sections built up from the innersection, which results in the outer-

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ENGINEERING INTEGRITY, VOLUME 31, SEPTEMBER 2011 pp.6-17.

Figure 7: Equivalent continuous stepped-beam (third angle projection) section having a smaller dimension: 23mm Ă— 23mm having retained a 1 mm wall thickness. For the present analysis, the stepped section is reduced down from the outer-section, so that the resulting inner-section will have the larger dimension: i.e., 19mm Ă— 19mm for the end-view 2 in Fig. 7. Referring to Fig. 8, the maximum bending tensile stress for the assembly occurs along the top surface. The maximum shear stress occurs along the neutral plane. These maxima are used as the comparative measure for a scaled-down model under a tip load of 30 N.

Figure 8: Sectional view of the continuous stepped-beam sections is outlined in Appendices A1-A3. Firstly, in A1, the tip reactions are calculated from the formulae given in Part 1 [1]. In A2 the shear forces and moments are calculated from the tip reactions and the applied loading for the beam ACB. The resulting S- and M-diagrams appear beneath this separated beam in Fig. 9. In A3 the bending and shear stresses are calculated from applying Eqs 1-3 to the required Table 3: FEA for the continuous beam

3.4 Finite Element Analysis of the Continuous Cantilever Details of the continuous stepped-beam, provided in section 3.3, were submitted to ABAQUS for FEA. Table 3 shows the FE procedure as a flow chart with detailed explanations given on the right-hand side. 4.0 Stress Analyses for the Telescopic Cantilever The maximum bending stress comparison between the two techniques refers to the midwidth position at the top surface. This follows the line A1C1B1E1D1F1 between sections in Fig. 8. The maximum shear stress comparison refers to the mid-thickness of the walls lying upon the neutral plane. This follows the line A2C2B2E2D2F2 for one wall in Fig. 8. 4.1 Force Diagrams

and

Moment

A sample of the shear force and bending moment calculations required for one of the individual

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ENGINEERING INTEGRITY, VOLUME 31, SEPTEMBER 2011 pp.6-17.

positions in this beam’s section. Because of the reduced scale in the model, units of N and mm are used throughout in all these calculations. Similar calculations apply to the remaining beams for which full details have been given elsewhere [1]

this telescopic assembly where the bending stresses are also zero. However, the surface bending stress in the connecting tube is not zero at these positions. Here the reinforcement of the section area from within the overlap plays no part in the stress reduction, lying at the ends of the linear regions for beams AB, CD and EF, as shown. The reduction in stress across these regions is due entirely to the manner in which the bending moment diminishes with length. Within each overlap, away from its free-ends, the area reinforcement becomes effective, serving to equalise stress at the mid-position, as shown. It will be seen that this bending stress distribution has its greatest variation across the overlap compared to equivalent portion of the continuous stepped-beam. The greatest bending stress magnitude of 146 MPa in this figure shows that the structure would remain elastic, given a yield stress for a medium carbon steel of, say, 400 MPa. Their ratio, which provides safety factor approaching 3, would be regarded as an adequate figure for a practical design but a lower factor might be applied to achieve a weight reduction. Here we should note that the minimum safety factor is based upon the greatest stress which applies to the fixed-end only. A fully optimised cantilever design would employ tapered contoured beams as a means of maintaining a uniform safety factor throughout its length [5]. Figure 10 reveals that a similar, optimal design criterion may be applied to telescopic structure. 4.3 Shear Stress Distributions for a Telescopic Cantilever

Figure 9: Shear force (N) and bending moment (Nmm) diagrams for each beam 4.2 Bending Stress Distributions Figure 10 compares the bending stress distributions obtained analytically and numerically (thin and thick lines respectively). The unreinforced beam lengths AB, CD and EF are shown for which the stress axis refers to the maximum bending stress at their mid, outer surfaces. These stress values were obtained at 50 mm intervals along the top of the beam sections, as shown in Appendix A.3. FEA values of bending stress were obtained in the manner outlined in Table 2. The stress dips from FEA at lengths of 600 mm and 1500 mm can be explained by the presence of wear pads; they decrease the stress concentration in the overlap area between sections. Before and beyond each overlap the bending stress in each is seen to diminish from its greatest value at the fixed-end to zero at the free-end. Figure 10 shows that there are four further ‘free-ends’ within

Figure 11 shows the graphical comparison between the shear stresses obtained analytically with those from FEA (thin and thick lines respectively). Shear stress values apply to the mid-wall position upon the neutral plane, where they take their maximum value [2]. Analytical shear stress values were obtained at 50 mm length intervals within the neutral plane, as shown in Appendix A3. FEA values of shear stress were obtained directly from the telescopic beam assembly model (see Table 2). The overlay between the two shear stress distributions in Figure 11 is self-validating. Both show that the shear stress remains fairly uniform along with the shear force across the unreinforced lengths. The tip reactions enhance both this force and its stress within the overlap where, again, the shear stress is fairly uniformly distributed with the shear force (see Fig. 9). The reversal in the tip reaction between beams AB and CD and again between CD and EF is responsible for the alternation in sign of the shear stress within Fig. 11. Nowhere does the shear stress magnitude become zero despite it having a relatively low magnitude compared to the accompanying bending stress. As a design criterion, the application of a limiting shear stress becomes important to shorter length cantilever beams. This imposes a near uniform crosssection when minimising weight [5], in marked contrast to the taper imposed by an optimised bending design mentioned above.

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ENGINEERING INTEGRITY, VOLUME 31, SEPTEMBER 2011 pp.6-17.

Figure 10: Telescopic beam bending stresses from FEA and tip reaction analysis (Key: _______ Analytical; FEA) Figure 12: Single Beam Model

Figure 11: Telescopic beam shear stresses from FEA and tip reaction analysis (Key: _______ Analytical; FEA) 5.0 Stress Analysis for the Continuous Beam 5.1 Force and Moment Diagrams Appendix B1-B3 outlines the analysis of the single beam model idealised, in Figure 12. The shear force and bending moment diagrams, shown in Figure 13, have been constructed from the S- and M-values given in B1. Section B.2 gives a sample calculation for the bending and shear stresses compared in Figures 14 and 15.

5.2 Bending Stress Distributions for a Single SteppedBeam Bending stresses refer to the top surface of the single stepped beam where they attain their maximum values [3]. Analytical stress values were obtained at 50mm intervals along the beam, as shown in Appendix B.3. Numerical values of bending stress were obtained directly from FEA. Figure 14 compares the bending stresses obtained from each method (thin and thick lines respectively). Here the

12

Figure 13: Shear force and bending moment diagram for the continuous, stepped beam

stress distribution, are those for a continuous beam, but due to its stepped changes in area, stress discontinuities again appear. The corresponding stepped stress reductions differ from those found within the overlaps in a telescopic cantilever (see Fig. 10) despite the area having been


ENGINEERING INTEGRITY, VOLUME 31, SEPTEMBER 2011 pp.6-17.

increased by a similar amount. We have seen that in an overlap one area bears far more stress than the other with the greater showing here a two-fold increase over the stepped beam value. This reveals an inherent feature of telescoping: that each beam end within the overlap must be stressed separately as they cannot be considered in terms of an equivalent solid section. It is instructive here to make a further comparison between the overall bending stress distributions in Figs 10 and 14 when the overlaps are ignored. Thus, the maximum stress in both beams decreases linearly from its greatest value at the fixed-end to zero at the free-end, where the load acts. The overall stress appears to be distributed linearly along the entire length of the single beam when the thicker section interruptions are ignored. In contrast, due to the tip reactions, the overlap displaces the distribution to retain a similar stress magnitude at its start and finish. Within the overlap these each fall to zero at the ‘free-ends’ on either side as shown. Comparing the overlap regions in the telescopic beam with each region of increased area for the single stepped beam, the stress reduction is less severe for the former due to the effect of the reactions that exist either at the tip positions (analytical) or the equivalent reactions spread within the wear pad (FE). However, the stress variation is greater across the overlap as it falls to zero at each end. The greatest bending stress magnitude of 140 MPa in this figure shows that the structure remains elastic, given a yield stress for a medium carbon steel of, say, 400 MPa. Their ratio, which provides safety factor of almost 3, would be regarded as an adequate figure for a practical design but a lower factor might be applied to achieve a weight reduction.

shear stress occurs in the smallest cross-section for the free-end length as shown. The greatest deviation between the two predictions in Fig. 15 occurs at the step where there appears an almost twofold increase in the peak value from FE. Here the FE is likely to be more realistic given what is known of the effect of sharp section changes upon stress concentrations [6]. Everywhere the shear stress remains positive albeit of small magnitude compared to the bending stress values. This will always apply to long beams but for shorter beams, where section dimensions are similar to the length, shear can dominate. In fact, shear stress remains an important design criterion for thin-walled sections whose plates are at risk of local buckling in a shear mode [5].

5.3 Shear Stress Distributions for a Single-Stepped Beam

Figure 14: Continuous beam bending stresses from FE and Theory (Key: _________ Analytical; FEA)

Shear stress values apply to the neutral planes of the beam sections where their maximum values are attained [3]. Analytical shear stresses were found at 50mm intervals along the neutral plane as shown in Appendix B3. Numerical values of shear stress were obtained directly from the telescopic beam assembly model using FEA. Comparing Figs 13 and 15, the most significant difference between the two shear distributions is the alternation to the sign of the shear stress for the telescopic cantilever. This is a consequence of the reversal in the tip reaction between mating sections which, of course, is absent in a continuous beam. For the latter, nowhere is the bending stress and the shear stress zero despite their being lowered by the increase in the section area at each step. The stress shear magnitudes for telescopic and continuous beams are similar at the fixed end and are fairly uniformly distributed within the unreinforced lengths. The shear stress in the continuous beam does not alternate between positive and negative values but the stepped geometry provides a distribution that is influenced by the changing cross-section. The greatest

Figure 15: Continuous beam shear stresses from FE and Theory FEA) (Key: _________ Analytical;

13


ENGINEERING INTEGRITY, VOLUME 31, SEPTEMBER 2011 pp.6-17.

7.0 Conclusions RD =

The graphs of the beam stresses provided by applying the two methods as well as a Finite Element Analysis to each structure respectively are presented for comparison. On comparison, it can be seen that there is a definitive correlation between them. As mentioned earlier these are self validating in nature, in that the continuous beam theory provides a check upon numerical stress levels from FEA and, in turn, FEA provides a check upon the analytical stresses calculated from tip reactions within a telescopic beam. Whereas the paper preceding this outlined the Tip Reaction Model, as an appropriate mechanism for telescopic beams, taking into account their discontinuity, this paper takes it a step forward, by obtaining beam stress values for the same and then comparing it with the established classical theory. Comparable stress values, confirms that the model proposed is perfectly robust for application to a telescopic cantilever, just as is the classical theory for continuous beams. Given that telescopic cantilevers are finding increasing applications in today’s world of material and design optimisation, with the focus on weight saving in engineering applications, this theory for discontinuous beams counterbalances the need for a numerical solution and can be adapted as is needed for any given purpose.

wl 

1 

1200 × 0.005652   = 133.5648 N 2 

Similarly taking moments about D gives

RE =

=

1 

W × (1 − α 2 ) + α 2 

w3l3 (1 − 2α 2 )   2 

1  0.005652 × 1200(1 − 0.5)  30 × (1 − 0.25) +  = 96.7824 N 0.25  2 

Similarly taking moments about C gives

RB =

RB =

1

α1 1

α1

[ RD + w2 ×

l2 l − RE × (1 − 3 α 2 )] 2 l2

[ RD + 0.006594 ×

1200 − RE × (1 − α 2 )] 2

From earlier calculations RD = 133.5648N and RE = 96.7824N

∴ RB =

References

1

α1

[133.5648 + 0.006594 ×

1200 − 96.7824 × (1 − α 2 )] = 194.8032 N 2

1. Abraham, J. Estimating deflection and stress in a telescopic cantilever beam using the tip reaction model, Ph.D. Interim Report, School of Engineering and Design, Brunel University, November, 2010. 2. Rees, D. W. A. Mechanics of Solids and Structures, World Scientific, 2000. 3. Gere, J. M. and Timoshenko, S. P. Mechanics of Materials, Van Nostrand, 1984. 4. Benham, P. P. and Crawford, R. J. Mechanics of Engineering Materials, English Language Book Society/ Longman Group Limited, Essex, England, 1987. 5. Rees, D.W.A. Mechanics of Optimal Structural Design – Minimum Weight Structures, Wiley 2008. 6. Peterson, R. E. Stress Concentration Factors, Wiley 1974.

Thus when l1 = 1000, l2 = 1200, l3 = 1200, α1 =

APPENDIX A

At the fixing A the reaction is:

A1. Tip Reactions

RA = 30 + 0.007536 x 1000 + 0.006594 x 1200 + 0.005652 x 1200 = 52.2312N

Referring to Fig. 3a, the tip load is W = 10 N and the distributed self-weights are N/mm, w1 = 0.007536 w2 = 0.006594 N/mm and w3 = 0.005652 N/mm. Equations, derived in Part 1 [ ], provide the tip reactions RD, RB and RC in Fig. 3a-d:

RD =

14

1 

W + 33 = 30 + 2  0.25  α 2 

1 

wl 

W + 33 2  α 2 

Balancing forces give

RB + RE = RD + 0.006594 × 1200 + RC RC =194.8032 + 96.7824 - 133.5648 - 0.006594 x 1200 = 150.108N

1 and α 2 = 0.25 3

the reactions are RB = 194.8032 N RC = 150.108 N RD = 133.5648 N RE = 96.7824 N

And the bending moment is M A = (30 × 2700) + (0.005652 × 1200 × 2100) + (0.006594 × 1200 × 1200) + (0.007536 × 1000 × 500) = 108506.4 N mm


ENGINEERING INTEGRITY, VOLUME 31, SEPTEMBER 2011 pp.6-17.

A.2 Shear Force and Bending Moment Diagram for beam ACB Length AC Shear force is = 52.2312 - 0.007536 × x where x is the distance from A. Bending moment

Figure C.1: Section of the Beam above the Neutral Plane

x = −108506 .4 + (52.2312 × x − 0.007356 × x × ) 2

The centroid of the section’s half-area above the neutral plane is found from the square tube’s outer dimension d and common thickness t = 1 mm:

Therefore Shear force at

Bending moment at

 A −108506.4 N mm  C − 78524.2 N mm

y=

 

  d 1 d d  (d − 2) −  + × × 2  2 2 2 4   = = 2(d − 1) Ai

Ai yi

2

Length CB Shear force is = 52.2312 - 0.007536 × x + 150.108 where x is the distance from A.

(2(d − 2)(d − 1) + d ) = 2d 2

4(2(d − 1)

2

− 6d + 4 + d 8(d − 1)

2

2

=

3d − 6d + 4 8( d − 1)

Bending moment = −108506 .4 + (52.232 × x − 0.007536 × x ×

Therefore Shear Force at

C  B

x + 150.108 × ( x − 600)) 2

197.8176 N 194.8032 N

Area of cross section

=

C −78524.2 N mm Bending moment at  0 B

d d × 1 + × 1 + ( d − 2) × 1 = 2( d − 1)mm 2 2 2

The maximum shear stress follows from Eq. 5 as follows

τ Max = A.3 Calculation of Bending and Shear Stresses for Beam ACB Surface bending stress are maximum along the vertical plane of symmetry. Within the length AC for the beam AB in Figure 3, the bending moment at a distance x from A is M = − RB × (l1 − x) + RC × (l1 − a1 − x) − w1 × (l1 − x) ×

(l1 − x) 2

The maximum bending stress applies to the top surface where ymax = 12.5mm

σ Max =

− M × ymax − M × 12.5 = N / mm 2 I 9232

in which the sagging moment is positive. The shear force in AC is given by S = 52.2312 − 0.007488 × xN and the maximum shear stress lies at the mid-wall upon neutral plane in Fig. C1.

S × 2(d − 1) × (3d 2 − 6d + 4) S × (3d 2 − 6d + 4) = 8(d − 1) × I × 2t 4 I × 2t

Note: The b denominator in τ =

Say in this case is equal to Ib

2t. Within the overlap length CB for beam AB the bending moment is

M = − RB × (l1 − x ) − w1 × (l1 − x) ×

(l1 − x) 2

Once again the maximum bending stress applies to the top surface where ymax = 12.5mm

σ Max =

− M × ymax − M × 12.5 = N / mm 2 I 9232

in which the sagging moment is positive. The corresponding shear force expression is

15


ENGINEERING INTEGRITY, VOLUME 31, SEPTEMBER 2011 pp.6-17.

S = 52.2312 − 0.007536 × x + 150.108 N

Length CB

The maximum shear stress follows from Eq. 5 as follows

Shear force is = 52.2312 − 0.007536 × x − 0.006594 × ( x − 600) where x is the distance from A. Bending moment

τ Max =

S × 2(d − 1) × (3d 2 − 6d + 4) S × (3d 2 − 6d + 4) = 8(d − 1) × I × 2t 4 I × 2t

x = −108506 + (52.2312 × x − 0.007536 × x × ) − 0.006908 × 2 × ( x − 600) ×

Note: The b denominator in τ =

Say in this case is equal to Ib

2t where t=1mm, from Table1. APPENDIX B Analysis of the Single beam Model Referring to Table 1 and Fig. 15 it is appropriate here to construct the S and M-diagrams for the full continuous, stepped length ACBED. However, only a sample of the stress calculations is given; namely those for length portions AC and CB.

( x − 600) ) 2

C Therefore Shear force at  B

197.8176 N 194.8032 N

C −78524.2 Nmm Bending moment at  0 B Length BE Shear force is = −150.108 − 0.006594 × ( x − 600) where x is the distance from A. Bending moment

B1. S- and M- Calculations (Units: N and Nmm) Length AC Equating forces in the vertical direction and taking W = 30 N, gives the reaction at A

= −108506 + (52.2312 × x − 7.488 × ( x − 500)) − 0.006594 ×

RA = [(0.007536× 600) + (0.014444× 400) + (0.006908× 500)

B Therefore Shear force at  E

= 52.2312N ) + (0.01319 × 300) + (0.00628 × 900) + 30] = 52 .2312 N The bending moment at A is

× ( x − 600) ×

( x − 600) ) 2

42.0576 N 38.7606 N

 B −60570.7 Nmm Bending moment at   E − 40366.2 Nmm

M A = (30 × 2700) + (0.00628 × 900 × 2250) + (0.013188 × 300 × 1650) × × 800=) + ++ (0.006908××500 ××1250) ++ ( 0.014444×× 400

+ (0.007536 × 600 × 300) = 108506 N

The shear force in AC at a distance x from A is

= −150.108 − 0.006594 × ( x − 600 ) + 194.8032 + 96.7824 where x is the distance from A. Bending moment

S(x) = 33.3616 − 0.00753 × x

= −108506 + (52.2312 × x − 7.488 × ( x − 500)) − 0.006594 × ( x − 600) ( x − 1500 ) ( x − 600) ) − 0.005652 × ( x − 1500 ) × 2 2

The bending moment in AC at a distance x from A is

x M(x) = −108506 + (52.2312 × x − 0.007536 × x × ) 2 The linear and parabolic expressions give their extreme values at A and C:

 E −96.7824 N Therefore Shear force at   D − 98.478 N

A Shear force at  C

52.2312 N 47.7096 N

 A −108506Nmm Bending moment at  C − 78524.2 Nmm

16

Length ED Shear force is

0 E Bending moment at  D − 29289 .1Nmm  Length DF Shear force is = 52.2312 − 7.488 − 0.006594 × 1200 − 0.005652 × ( x − 1500) where x is the distance from A.


ENGINEERING INTEGRITY, VOLUME 31, SEPTEMBER 2011 pp.6-17.

Bending moment

x M = −56541.4 + (33.3616 × x − 0.007536 × x × ) − 0.006908 × 2

= −56541.4 + (33.3616× x − 7.488× ( x − 500) − 0.006594×1200× −

( x − 1800) ) × ( x − 1200) − 0.005652 × ( x − 1800) × 2

( x − 600) ) 2 Taking sagging moments as positive, and referring to Table 1 for the corresponding second moment of area for the length BC (Section 4), the maximum bending stress follows from Eq. 4:

006908 × ( x − 600) ×

 D 35.0868 N Therefore Shear force at  30 N F  D −29289.1Nmm Bending moment at  0 F The shear force diagram and the bending moment diagram for the continuous beam are shown in Figure 12.

σ Max =

− M × ymax − M × 12.5 = N / mm 2 I 16345

The accompanying shear force is B.2 Calculation of Bending and Shear Stresses Consider the sectional view of the continuous stepped beam shown in Figure 6. The maximum bending stress apply to line A1C1B1E1D1F1 in Fig. 9. The shear stress will be maximum along the line A2C2B2E2D2F2. Note that the area properties given in A3 again apply to each square tubular section of outer dimension d and thickness 1 mm. Length AB Consider, firstly, the uniform section within the length portion AC. The bending moment at the section at a distance x from A

S = 33.3616 − 0.007536 × x − 0.006594 × ( x − 600) The maximum shear stress follows from Eq. 5 as follows

τ Max =

S × 2(d − 1) × (3d 2 − 6d + 4) S × (3d 2 − 6d + 4) = 8(d − 1) × I × 2t 4 I × 2t

Say in this case is equal to Ib 2t where t=2mm and I =16345N/mm2 from Table1.

Note: The b denominator in τ =

x M = −56541.4 + (33.3616 × x − 0.007536 × x × ) 2

Taking sagging moments as positive, the maximum bending stress follows from Eq. 4:

σ Max =

− M × ymax − M × 12.5 = N / mm 2 I 9232

The shear force in AC is given by S = 52.2312 − 0.007488 × xN The maximum shear stress follows from Eq. 5 as follows

τ Max =

S × 2(d − 1) × (3d 2 − 6d + 4) S × (3d 2 − 6d + 4) = 8(d − 1) × I × 2t 4 I × 2t

Say in this case is equal to Ib 4 2t where t=1mm and I = 9232 mm from Table1.

Note: The b denominator in τ =

Length BC For the stepped length CB, the bending moment is

17


Technical Article Mechanical Testing of Micro Specimens and Semi-finished Micro Products Bernd Köhler*, Hubert Bomas*, Hans-Werner Zoch*, Bremen, and Jens Stalkopf°, Pfungstadt *IWT Stiftung Institut für Werkstofftechnik, Bremen, Germany ° Instron Deutschland GmbH, Pfungstadt, Germany

Established in 2007, the Collaborative Research Centre 747 “Micro Cold Forming - Processes, Characterisation, Optimisation” of the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) focuses on the provision of processes and methods for the manufacture of metallic micro components through metal forming technologies. The Project B4, Component Strength, deals with the static and dynamic investigation of the mechanical properties of micro specimens and semi-finished micro products. Mechanical testing of such micro specimens requires testing equipment specifically adapted to their small dimensions. Within the context of this special requirements profile, this paper discusses the comparative advantages of different testing machine types available on the market. To conduct the above-mentioned project, the testing system considered to be most appropriate for the task was procured, consisting of the Instron Electropuls™ E1000 electromechanical test machine equipped with the non-contacting Advanced Video Extensometer AVE. This article discusses some of the insights gained in the use of this testing system.

For this reason the mechanical properties of the manufactured semi-finished products and their post-forming behaviour in the finished component have to be analysed thoroughly, including their behaviour during failure, with a view to validating calculation methods and transferability of mechanical properties. Such analyses necessitate a testing system capable of meeting the specific requirements for static and cyclic testing of micro specimens. The system has to allow low forces and strokes to be set and controlled with sufficient accuracy, and provide for a method of strain measurement which takes into account the mechanical sensitivity of the test specimens. For the last two years, the Collaborative Research Centre has had a materials testing system of this type at its disposal. The following article will discuss some of the experience gained with this system.

The Collaborative Research Center 747 of the Deutsche Forschungsgemeinschaft “Micro Cold Forming - Processes, Characterisation, Optimisation” was established at Bremen University in 2007. The central focus of this Collaborative Research Centre is the investigation of processes and methods for the manufacture of metallic micro components by means of metal-forming technologies, i.e. of components which are smaller than 1 millimetre in at least two dimensions, and less than 5 mm in the third dimension [1]. These investigations encompass all relevant aspects of the forming process, from the development of materials to components testing.

1. Loads:

In this context, the Project B4, in which three of the authors work, deals with the determination of the mechanical properties of thin metallic semi-finished products, and components manufactured from these products, which, in general, cannot be derived from those of semi-finished products and components with significantly higher wall thickness. This is due to the statistical and technological effect of size, the dominant influence of surface, and dimensions in the scale of the material’s microstructure. Micro sheets with a sheet thickness in the order of the grain size of the material, for example, exhibit mechanical properties which are significantly different from those of larger-thickness sheets.

18

Test machine for micro specimens Critical requirements for a testing system for micro specimens and micro components, which is to permit both static and cyclic investigations, fall into three areas: Materials and specimen dimensions determine the load range to be covered by the test machine. Specifically with a view to dynamic testing, the machine must allow for precise control of low forces. 2. Dynamics: High dynamic performance of the machine is desirable, i.e. for a specimen with given material and geometry, the machine should provide for an adequate displacement amplitude at a maximum frequency of load cycles, whilst maintaining the preset waveform (e.g. a sine wave). 3. Stroke: To enable static tensile and compressive tests to be performed, an adequate piston stroke is required. As resonant testing machines do not permit static testing, and both, servo-pneumatic and spindle testing machines do not meet the above requirements with regard to dynamic performance and controllability, only electro-dynamic or servo-hydraulic machines are, in principle, suited to the application in hand. Electro-dynamically driven test machines are available on the market in various sizes with maximum load capacities ranging from ± 22 N up to ± 10 kN. By contrast, even the smallest servo-hydraulic systems provide a load capacity of


5 kN. Depending on the strength and dimensions of the specimens, the loads required for testing of micro specimens can be found predominantly in the range below 1000 N, whilst thin sheets with thicknesses in the range of 10 Âľm require forces of less than 10 N. Although electro-dynamic and servo-hydraulic systems basically exhibit a comparable dynamic performance when it comes to higher loads, even the smallest servo-hydraulic testing machines have been shown to be hard to control during cyclic tests with loads in the order of only a few Newtons, due to the relatively high moving masses of the machine. Besides, electro-dynamically driven machines are superior to their servo-hydraulic counterparts in a number of other ways which are shown in Figs 1 and 2 using the example of two 10 kN machines.

Figure 2. Electrodynamic testing machine

testing of micro specimens, an electro-dynamic testing machine type Instron E1000 (see Fig. 3) was considered the ideal solution.

Figure 1. Servohydraulic testing machine Due to the absence of the hydraulic power pack, the electrodynamic testing system has a lower footprint. It does not require a 3-phase power supply or a cooling water connection and is less maintenance-intensive, as there are no hydraulic hoses to replace, no oil filters or seals to change, no oil to be replaced and properly disposed of, and no maintenance of servo valves is required. In addition, the testing system is characterised by low noise emission. The electro-dynamic drive concept is therefore clearly superior to the servo-hydraulic concept considering the requirements profile for testing of micro specimens. Apart from their maximum load capacity, electro-dynamic testing machines available on the market also differ with regard to their maximum stroke, which is particularly relevant in the case of static tensile tests. Some of the test machines have a maximum piston stroke of 25 mm or less. Some electro-dynamical testing machines even require a costly additional drive unit to apply the static load. Considering all relevant requirements for static and cyclic mechanical

Figure 3. Testing machine ElectropulsTM E1000

19


This test machine is driven by a brushless linear motor and provides a maximum load capacity of ± 710 N for static tests and ± 1000 N for cyclic tests. The machine’s test space has a height of max. 610 mm, the maximum piston stroke is 60 mm, which is adequate for performing static tensile tests. The piston position is measured by means of a Linear Variable Differential Transformer (LVDT) in the setup mode, and by means of a calibrated incremental transducer in the displacement control mode. Two appendant Dynacell load cells calibrated to ISO 7500-1 with measuring ranges of ± 2kN and ± 250 N, respectively, and automatic inertia compensation are available for load measurement. Special attention was given in the selection of the test system to the accuracy of load control for small loads and in cyclic operation. Figure 4 shows the variation of the load amplitude for a cyclic tensile test under sinusoidal load at a stress ratio R = 0.1 and a frequency f = 20 Hz. The specimen was a micro rotary swaged wire made from steel grade 1.4301 with a diameter of 0.5 mm. The graph shows the feedback load amplitude at a command value of Fa = 40.5 N. The average load feedback amplitude determined over 2000 load cycles is F a = 40.487 N with a standard deviation of s = 0.055 N. The first 1000 cycles were not taken into account in the calculation of the mean value, to ensure that the result is not distorted by the process of stabilisation. Normalisation of the standard deviation with respect to the measuring range of the load cell used provides:

achievable displacement amplitude for three different loading conditions. The curve plotted without a specimen installed represents a limiting curve resulting from the maximum achievable acceleration of the moving masses. Looking at the plot with installed specimen at a static mean load of 200 N and a load amplitude of 100 N, you will find that a significant deviation from the limiting curve does not occur until a frequency above 100 Hz has been reached. When the mean load is increased to 500 N and the amplitude to 500 N, the curve shifts towards lower frequencies, i.e. a given displacement amplitude will not be achievable under these conditions unless the test frequency is reduced. Basically, the performance diagram shows that testing frequencies of 100 Hz can be achieved with the testing system in cyclic tests, provided that the stiffness of the specimen is adequate.

sn = s/250 N = 0.00022 = 0.022 %

Figure 5. Dynamic performance plot of the testing machine ElectropulsTM E1000 No-contact strain measurement

Figure 4. Fluctuation of load amplitude during cyclic test In contrast to mechanical testing with resonant testing machines, the linear motor driven electro-dynamic system enables the testing frequency to be varied within certain limits. The dynamic performance of the testing system is shown by way of example in Fig. 5 which illustrates the relationship between the testing frequency and the

20

In view of the micro dimensions of the test specimens (typical sheet thickness ranges between 10 µm and 100 µm), strain measurement using specimen-contacting methods such as strain gauges or clip-on extensometers is not feasible. On the one hand, such methods involve the danger of damaging the specimens during the attachment of the respective strain measurement device, on the other hand, the impact of these measuring methods on the result can no longer be neglected, as it can be with larger specimens. For this reason, a non-contacting optical strain measurement method was chosen. The system supplier provides such a solution as part of the ElectroPuls testing system in the form of the so called Advanced Video Extensometer (AVE), see Fig. 6. Essentially,


the AVE consists of a high-resolution digital video camera and an LED light source, which illuminates the specimen with pulsed, monochromatic, red, polarised light with a wavelength of 650 nm. For the application in hand, the video camera is configured with a lens system optimised for small specimens, which has a focal length of 55 mm and permits a viewing field of 60 mm in the axial direction, and 8 mm in the transverse direction. Strain measurement is achieved by tracing the axial movement of markings applied on the specimen with the video camera, and calculating strain by means of a realtime image processing system.

Figure 7. Gauge marks applied to a tensile specimen for the AVE reflections from the specimen surface and enabling optimum boundary definition between the marking and the specimen surface. In addition, an electronic bandpass filter in the camera ensures that only light with the wavelength of the mono-chromatic light source can pass, such that the influence of ambient lighting is eliminated. During the measurement, the centres of gravity of the markings are computed in real time and the strain is determined from their distance.

Figure 6. Video extensometer AVE (a) with integral illumination unit (b) Measurement of the original gauge length, which is defined by the markings on the specimen and which is essential for strain measurement, is achieved prior to the test by the calibrated AVE, with an absolute accuracy of ± 2.5 µm. The markings take the form of two spots with a diameter between 0.5 and 3 mm (Fig. 7), or alternatively lines with a thickness between 0.25 and 2.5 mm, which can be applied in different ways, e.g. by means of a suitable marker pen or by means of a template, or by means of adhesive spots. A suitable choice of colour has to be made to ensure adequate contrast between the marking and the background colour. In addition, a second polarisation filter in front of the camera lens works as analyser, suppressing undesirable

This eliminates potential errors due to a deformation of the markings under the influence of high strains. The minimum original gauge length, i.e. the distance between the markings at the beginning of the test, is 5 mm in the case of the camera lens used, maximum tracking speed for the markings is 150 mm/min. When the 55 mm lens is used, the resolution for displacement measurement is 0.5 µm, absolute accuracy is 2.5 µm or 0.5 % of gauge length, whichever is greater. Figure 8 shows the results of static tensile tests conducted on flat specimens with the shape shown in Figure 9. The test measured the yield strength Rp0.2, tensile strength Rm and elongation after fracture A of Al-99.5 micro sheets having a sheet thickness of 100 µm at various test velocities. The test system enabled the strain rate to be varied over more than two orders of magnitude, and the AVE enabled strain to be measured up to a nominal test velocity of 5 mm/s, equivalent to a strain rate of more than 0.2 s-1 Apart from measuring axial strain, the AVE also permits measurement in the transverse direction, meeting the requirements of ASTM E 8, EN 10001-1 and ISO 6892 for testing of metals.

21


Acknowledgements The authors would like to thank Deutsche Forschungsgemeinschaft (DFG) for their beneficial support provided during these studies within the framework of the Project B4 “Component strength” of the Collaborative Research Centre 747 “Micro Cold Forming – Processes, Characterisation, Optimisation”. Literature references 1

2

3 Figure 8. Mechanical properties of micro-flat-specimen of Al 99.5 (thickness 100 µm) in dependence of the strain rate

4

5

6 Figure 9. Sketch of the tensile specimen

With the help of the ElectroPuls testing system it has been possible, in cooperation with other Project Areas of the DFG Collaborative Unit, to make contributions in various fields: The further development of a PVD-based manufacturing process for AlSc micro sheets was supported by extensive studies of their physical properties [2]. In addition, the mechanical variables determined were used for the optimisation of micro cold forming processes such as deep drawing [3] and applied in FEM simulations [4]. Last, but not least, differences were observed in the mechanical properties of micro specimens [5], which can be attributed to typical size effects occurring on transition into the micro range [6]. On the whole, the test system described here has proven itself as a valuable and flexible tool for the DFG Collaborative Research Centre 747 for meeting the wide spectrum of requirements in the static and dynamic testing of micro specimens and components.

22

F. Vollertsen: Size effects in manufacturing, F. Vollertsen, F. Hollmann (Hrsg.): Strahltechnik vol. 24, BIAS Verlag Bremen (2003), S. 1-9, ISBN 3-933762-14-6. H.-R. Stock, B. Köhler, H. Bomas, H.-W. Zoch: Properties of aluminium-scandium alloy thin sheets produced by physical vapour deposition, Materials and Design, 31 (2010) 576-581. F. Vollertsen, Z. Hu, H.-R. Stock, B. Koehler: On the limit drawing ratio of magnetron sputtered aluminiumscandium foils within micro dee drawing, Prod. Eng. Res. Devel. 4, 5 (2010) 451-456. P. Bobrov, J. Lütjens, J. Montalvo Urquizo, W. Wosniok, M. Hunkel, A. Schmidt, J. Timm: Zu einer verteilungsbasierten Modellierung von Mikrowerkstoffen, F. Vollertsen, S. Büttgenbach, O. Kraft, W. Michaeli (Hrsg.): 4. Kolloquium Mikroproduktion, BIAS Verlag Bremen (2009), S. 235-242, ISBN 978-3-933762-32-0. B. Köhler, H. Bomas, J. Lütjens, M. Hunkel, H.-W. Zoch: Yield strength behaviour of carbon steel microsheets after cold forming and after annealing, Scripta Mat. 62 (2010) 548-555. F. Vollertsen, D. Biermann, H. N. Hansen, I. S. Jawahir, K. Kuzman: Size effects in manufacturing of metallic components, CIRP Annals – Manufacturing Technology 58, 2 (2009) 566-587.


Report on EIS Forum “Seven posters - is that three too many?” The forum took place at the annual EIS instrumentation exhibition at Silverstone on 8th March. It was chaired by Colin Dodds with an invited panel of guest speakers: David Hamer from Lotus Renault GP, David Purdy from Cranfield University, Defence Academy, Bruce Oliver from Lola Cars and Bernard Steeples ex Ford and now an engineering consultant. Colin opened the proceedings with a short presentation describing the 7-post application and how it differed from the classic 4-post road simulator and then, each guest speaker took it in turn to express his views on the subject before opening up the topic to short presentations and questions from the floor. Since the F1 application was the main interest at Silverstone the discussion focused more on the performance (ride and handling, leading to lap time) side rather than structural

integrity. A consensus agreed that the 7-post was best suited to refining dynamic response of a F1 car and had little application elsewhere whereas the 4-post system has a plethora of applications ranging from full vehicle durability, ride, packaging studies and dynamic response. The session closed with a presentation by Chris Lamming from the University of Bath who discussed control techniques for aero-loaders. The feedback was positive from a number of attendees and this type of forum may become an annual event coupled with the instrumentation exhibition. However, there was fear that the forum detracted from attendance at the exhibition; the exhibition attendance was small in the afternoon. This should be resolved prior to introducing the forum as an annual event. That said, the forum was a success.

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Industry News Welcome to the Industry News section of the journal. Thank you to everyone for their submissions, of which we received over 500 press releases. The nominal limit for entry is 200 words, which should be sent to eis@amberinstruments.com or posted to EIS, c/o Amber Instruments Ltd, Dunston House, Dunston Road, Chesterfield, S41 9QD. We would appreciate you not sending entries by fax. Paul Armstrong

Exeter study brings brain-like computing a step closer to reality The development of ‘brain-like’ computers has taken a major step forward with the publication of research led by the University of Exeter. Published in the journal Advanced Materials and funded by the Engineering and Physical Sciences Research Council, the study involved the first ever demonstration of simultaneous information processing and storage using phase-change materials. This new technique could revolutionise computing by making computers faster and more energy-efficient, as well as making them more closely resemble biological systems. Computers currently deal with processing and memory separately, resulting in a speed and power ‘bottleneck’ caused by the need to continually move data around. This is totally unlike anything in biology, for example in human brains, where no real distinction is made between memory and computation. To perform these two functions simultaneously the University of Exeter research team used phasechange materials, a kind of semi-

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conductor that exhibits remarkable properties. Their study demonstrates conclusively that phase-change materials can store and process information simultaneously. It also shows experimentally for the first time that they can perform generalpurpose computing operations, such as addition, subtraction, multiplication and division. More strikingly perhaps it shows that phase-change materials can be used to make artificial neurons and synapses. This means that an artificial system made entirely from phase-change devices could potentially learn and process information in a similar way to our own brains.

CPT receives investment boost for its ‘green’ car technology The UK Low Carbon Innovation Fund (LCIF), based at the University of East Anglia (UEA), has invested £400,000 in new automotive technologies designed to improve fuel efficiency and reduce carbon emissions. Controlled Power Technologies (CPT) has developed a range of products to help car makers meet tightening legislation on CO 2 emissions by making the car significantly more fuel efficient, through mild electric hybridisation, without the need to redesign the car or the car engine. The UK Essexbased specialists have a range of products currently in development. CPT chief executive Nick Pascoe said: “Although we are now working on applications around the world, our products and technologies have all been developed by our experienced

and growing team of engineers in the East of England and we are proud of our roots here. LCIF joins the list of our major shareholders at an exciting stage as we work to bring our more developed products to market. We welcome and appreciate LCIF’s support and its recognition of the fruits of our work since the launch of CPT in 2008.” Launched in 2010, the Low Carbon Innovation Fund is part of a £20 million venture capital investment programme, including an £8m contribution from the European Regional Development Fund. The fund, which is based at the University of East Anglia, invests in SMEs across the East of England – a region which aspires to become a leading, world class low carbon economy. Companies interested in seeking investment from the fund should contact Kevin Murphy on 0207 2481506. Further details can be found at www.lowcarbonfund.co.uk and www.cpowert.com/

UK first as TfL installs eco-lighting in a London road tunnel In a UK-first, innovative, eco-friendly lights have been installed in a central London tunnel by Transport for London (TfL) helping to improve safety, reduce maintenance closures as well as cut energy consumption and costs. The Upper Thames Street westbound tunnel is now entirely lit with low energy, long-life LED (Light Emitting Diode) lights providing a host of benefits for Londoners. The design and colour of the lights is designed to improve visibility for


cyclists and motorists to boost safety. The lights will also cut CO 2 emissions by more than 60 per cent compared with conventional systems, helping to reduce TfL’s energy bills. Projections show the cost of lighting the tunnel could fall from around £50,000 each year to less than £10,000, delivering a potential annual saving of at least £40,000. The innovative lights are also expected to last for 20 years as opposed to the existing system’s two year life span, significantly reducing the need for maintenance closures. Upgrading the lighting system in Upper Thames Street tunnel is just one way the Mayor of London and TfL are working together to make the Capital cleaner and greener. London is already leading the way on the introduction of hydrogen buses and electric vehicles while the Capital’s cycle revolution is increasing the numbers of bikes on the streets and improving cycling safety. Subject to funding, it is hoped that further schemes can be developed across London, delivering further benefits to road users across the Capital.

‘Walking Chair’ could be step-up for disabled access A student inspired by moving sculptures has designed a prototype ‘walking chair’ that he hopes could go on to give people with mobility problems greater freedom. Martin Harris, 21 – who is about to complete his BA (Hons) Product Design degree at the University of Derby – developed his batterypowered chair, which uses metal legs instead of wheels, after seeing

the ‘walking sculptures’ of Dutch artist and engineer Theo Jansen. Martin, originally from Birmingham, said: “I first saw Theo Jansen’s work many years ago, he calls the walking sculptures Strandbeests . The walking mechanism had so much potential and I wanted to put it to a practical purpose.” Instead of wheels the chair moves on a dozen legs, six on each side, which are made up of 216 separate pieces bolted together. The ‘one size fits all’ seat is completely adjustable, so it will comfortably accommodate anybody. The prototype can move at the maximum wheelchair speed limit of four miles per hour. It is powered by standard wheelchair batteries and motors, which gives it a range of several miles on a single charge. Martin added: “Most motorised wheelchairs are optimised to work indoors or outdoors, not both. The walking chair is compact enough for use indoors whilst also having the all-terrain ability to cross soft surfaces, such as sand or grass, which can prove difficult for wheeled chairs. “This design is a prototype, and I’d be happy to see someone take up the concept and develop it further, for commercial use.”

Robotics Centre to pave the way for robots of tomorrow A groundbreaking new robotics centre set to make significant technological advances, including developing assistive robots to help children and adults with special needs, has been launched by the University of Sheffield and Sheffield

Hallam University. The Sheffield Centre for Robotics (SCentRo) will combine the expertise from both universities in a bid to boost research into the creation of animal-like robots, selfdriving cars, robots for the farms of the future and robots that can intelligently communicate with humans. Devices on display at this year’s Towards Automatic Robotics Systems ( TAROS) conference included: • Shrewbot - a unique animal-like robot that can seek out and identify objects with its artificial whiskers using a new technology that was developed jointly by the Active Touch Laboratory at the University of Sheffield and Bristol Robotics Laboratory. The technology will enable the robot to function in spaces where vision cannot be used. • Guardians – firefighter assisting robots developed by Sheffield Hallam University. • Grail - a robotic arm designed for use in domestic and catering scenarios developed by the University of Sheffield’s Department of Automatic Control and Systems Engineering. • The Tactile Helmet - a supersensing helmet being developed by the University of Sheffield’s Department of Psychology to help firefighters find their way in smokefilled buildings. The helmet works by detecting walls and obstacles through an ultrasound sensor which converts the signal to a tactile stimulus such as a buzz on the head when near a wall. SCentRo, visit: www.scentro.ac.uk

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Industry News The Infrastructure Show (NEC,Birmingham, 17-19 October) The show will offer visitors a fresh insight into major rail infrastructure projects alongside the opportunity to understand how these schemes are managed to reduce environmental impact and meet spending targets plus the chance to learn about the latest product and system innovations in the sector. A major highlight of the show will be its sector-focused hubs and Keynote Theatre, featuring expert speakers from Network Rail, Crossrail, HS2, London Underground and others in a series of free-to-attend talks. The Rail hub will also provide a forum for visitors to meet with specialist suppliers and manufacturers and see major project updates from the biggest clients. A diverse range of leading sector suppliers and manufacturers showcasing the latest product innovations will also be attending The Infrastructure Show. Among the major exhibitors already confirmed for the event are ACO Technologies, Cleshar Contract Services, Costain, CPM Group, CU Phosco Lighting, JCB, Peri Ltd, Severn Trent Services, Vinci Construction UK Korec Kosran, RMD Kwikform, Tony Gee & Partners and Topcon. A full exhibitor list is available from www.infrastructure-show.com

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London, including such measures as a ‘no-idling zone’, Bosch believes that the use of Start/Stop technology for vehicles in London could reduce CO2 emissions by over 500,000 tonnes annually. ”Bosch is at the forefront of developing technologies to make gasoline and diesel engines more efficient and less polluting”, said Peter Fouquet, President of Bosch in the UK. The system works by automatically switching off a vehicle’s engine when it comes to a stop, for example at traffic lights. When the clutch is depressed, or the foot is taken off the brake pedal for an automatic transmission, the engine restarts seamlessly in a fraction of a second. ”A Start/Stop system can reduce a vehicle’s CO2 emissions by 8 percent in average city driving, and up to 15 percent in dense city traffic. In addition, the technology also reduces noise pollution”, Fouquet said. “The benefit can be further improved when a Bosch ultraefficient alternator is added.” See Bosch’s Start/Stop system in action for vehicles with both manual and automatic transmissions via the following link: www.youtube.com/user/ boschautomotive

500,000 tonnes of vehicle CO2 emissions could be saved in London with Start/Stop technology

University doubts after ‘A’ level results? - Current students recommend a working gap year despite the fee increases.

Following the announcement by Transport Secretary Philip Hammond of the creation of a ‘Clean Air Fund’ to improve air quality in

Students struggling with their options in the light of their ‘A’ level results have clear advice from a survey of current university students who took

a working gap year with ‘The Year in Industry’ programme (YINI). They are overwhelmingly recommending that ‘A’ level students in relevant subjects should in principle go on the programme, with 94% of those surveyed saying they would recommend the programme, and, significantly, only one in six see the 2012 fee increase as presenting a strong reason not to undertake this career changing paid gap year in 2011/12. ‘The Year in Industry’ programme, run by educational charity EDT, specialises in placing students on a paid working gap year with leading engineering, technology or science companies. The survey results throw the benefits of a working gap year through “The Year in Industry” into sharp focus: • 94% said YINI had helped them decide their career preferences • 97% said YINI had made them more employable • 75% said it had helped them in their degree studies

Turing Bombe rebuild team leader recognised with honorary doctorate On the 4th June 2011, John Harper was among over 200 students receiving various qualifications from the Open University at Ely cathedral but what made John special was he was the only one receiving an honorary doctorate. The Open University presented John with this honour in recognition of his work, leading a team of talented volunteers to recreate the Turing Welchman Bombe at Bletchley Park. John Harper, a qualified chartered engineer, is a key member of those


visionary enthusiasts who undertook the long and complex process of recreating the technology of World War Two. He has been the driving force in preserving much historical material in danger of being lost, persuasively obtaining funding, industrial and governmental support, often in an environment of disinterest. The World War Two Bombe Rebuild is on public display at Bletchley Park, and is normally demonstrated at weekends. www.bletchleypark.org.uk

Dedication of Bletchley Park Memorial by HM The Queen Her Majesty The Queen dedicated a public memorial at Bletchley Park, Milton Keynes, Buckinghamshire on Friday 15 July, to commemorate all those that provided vital service at Bletchley Park and its ‘Outstations’ during World War II. This was The Queen and Duke of Edinburgh’s first visit to the home of the wartime code breakers. They were accompanied throughout the visit by Sir Francis Richards, Chairman of the Bletchley Park Board of Trustees and Simon Greenish, Director of the Bletchley Park Trust. The Royal Party was provided with a short tour of the museum and shown some of the restoration projects which have taken place at Bletchley Park to rebuild the machines which assisted with the wartime decryption of enemy codes. These included the Turing Bombe, brainchild of mathematical genius Alan Turing, and Colossus, the world’s first electronic computer. The Queen was also shown an Enigma machine and

given a demonstration of how it worked. Following the ceremony, The Queen was shown the Roll of Honour which lists the names of all of those who served at Bletchley Park and its ‘Outstations’ during the War. This has been compiled over a number of years and includes nearly 11,000 names. www.bletchleypark.org.uk

Engineers find leaky pipes with Artificial Intelligence University of Exeter engineers have pioneered new methods for detecting leaky pipes and identifying flood risks with technologies normally used for computer game graphics and Artificial Intelligence. These techniques could help to identify water supply and flooding problems more quickly than ever before, potentially saving people from the traumatic experience of flooding or not having water on tap. Existing methods for detecting leaks often result in false, so-called ‘ghost’ alarms. University of Exeter engineers have developed a new approach, based on technology originally developed in the field of Artificial Intelligence. The new technology is implemented as a piece of software located on a computer in the control room of a water company. The software continuously receives and processes data coming from the flow and pressure sensors installed in the water system. It then searches for anomalies indicating the presence of the leak. When a potential problem is identified, an alarm is generated to notify the control room operator. The operator

also receives information on the likely location of the leak and suggestions of immediate actions to take to isolate it.

F1 in Schools™ out and about at Silverstone, London, Goodwood and Grove. F1 in Schools™ had a busy couple of weeks in July with the initiative flying the flag for young engineering talent and showcasing winners of its innovative Formula 1™ linked education programme at a number of high profile events. The Santander Formula 1 British Grand Prix was the highlight of the year for winners of F1 in Schools 2011 National Finals Awards, with eight teams visiting this prestigious event on the British sporting calendar. Prior to the Grand Prix weekend the reigning UK F1 in Schools champions, ‘Dynamic’, from St. John Payne Catholic Comprehensive School in Chelmsford, Essex, were guests of Hilton Racing for a high profile media event, the Hilton on Park Lane Pit Stop Challenge. A group of UAE primary school students flew in to the UK to link with the Bloodhound SSC land speed record project at the Goodwood Festival of Speed earlier this month and this week teams of 9-11 year old primary school students competed at the T1 Primary Racing Challenge 2011 finals, supported by F1 in Schools, held at the Williams F1 team HQ. For further information about F1 in Schools visit www.f1inschools.co.uk.

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Product News New release of computing software The latest, substantial new release of Maple™, the flagship technical computing software for mathematicians, engineers and scientists from Maplesoft™ (Waterloo, Canada), has over 270 new mathematical functions and over a thousand enhancements to existing algorithms. Now available from Adept Scientific (Letchworth, Herts), Maple 15’s record-breaking solvers for differential equations is just one of many new advances in Maple 15 which enables customers to solve more complex problems even faster.

offering users the latest technologies as part of the complete vibration test solution from Brüel & Kjær. Both of the new variants promise to save time and simplify testing procedures by virtually guaranteeing signal underranges and overloads are eliminated. This is thanks to dual, parallel A/Ds that deliver an exceptionally wide 130 dB dynamic range for the input channels, without the need for programmable voltage range circuitry. Bruel & Kjaer, Royston, Herts. Tel: 01763 255 780, www.bksv.com Net shape steel and titanium castings

Adept Scientific, Letchworth, Herts. Tel: 01462 480055. Email:leads@adeptscience.co.uk

10 MHz USB data acquisition module with two isolated Analog inputs Data Translation announces the release of a cutting-edge data acquisition module that sets new standards in 16-bit high-speed data acquisition via USB 2.0. With up to 10 MHz signal sampling and direct streaming to the PC, the new DT9862 can provide twice the USB throughput rates achievable with comparable solutions currently available on the market. All I/O channels are galvanically isolated to ensure ultra-high measurement accuracy and signal integrity. In addition, the new module also features flexible clock and trigger functions (e.g. pre-, post- and abouttrigger modes). Data Translation GmbH, Germany. Tel: +49 (0)7142/95 31-0. www.datatranslation.eu

Over the years, Castings Technology International (Cti) has perfected the manufacture of castings from precision-machined polystyrene patterns. As in the Lost Wax process, layers of ceramic are built up on the pattern, which is removed on firing to leave an inert ceramic shell mould. These can be used to produce prototype Replicast® castings and to meet a market need for short lead-time, one-off and low volume castings. More recently the MEGAshell ® technology has enabled exceptionally large ceramic shell moulds to be produced to deliver the benefits of Replicast ® of a size and weight far greater than most casting manufacturers would have believed possible. Castings Technology Int., Rotherham, South Yorks. Tel: 0114 2541166, Email: m.ashton@castingstechnology.com, New low energy solenoid valves from Gems Sensors give fast response and high flow

Good vibrations Sound and vibration leader, Brüel & Kjær, has released its next-generation vibration controller. Type 7541 and 7542 vibration controllers are designed to meet the requirements of vibration testing for production test applications,

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Gems Sensors & Controls, a global market leader in fluid sensing and control solutions, has introduced the energy efficient E Series family of pneumatic solenoid valves, specifically engineered to give fast response and high flow rates in a wide range of air

and dry gas applications. The fast response times, combined with high pressure and flow capabilities, make the E-Series solenoid valves ideal for use in a wide range of applications, including medical and respiratory healthcare instruments, printing machinery and sorting equipment, automated packaging and air monitoring systems. Gems Sensors and Controls, Basingstoke, Hampshire. Tel: +44 (0)1256 320244. Email: sales@gems-sensors.co.uk Electric motion control system for Wimbledon Centre Court retractable roof Moog Industrial Group, a division of Moog Inc. (NYSE: MOG.A and MOG.B) has signed a new 5 year contract with SCX Special Projects, Sheffield, UK to continue its support of the motion control system for the Wimbledon Centre Court Retractable Roof, London until August 2015. The new service and support contract is managed by Moog’s operation based in Tewkesbury, UK. Since the installation of the retractable roof in 2009, Moog’s motion control system has helped ensure uninterrupted play during all weather for tennis fans worldwide throughout the 2009 and 2010 Wimbledon Championships. The new contract is now set to continue this successful run until 2015. Easy to use modular test controller from MOOG handles wide range of tasks Moog’s latest test controller is intended for simple and complex tests on components, materials and vehicles. The new Modular Test Controller is the latest addition to a family that already includes larger units dedicated to aerospace and automotive testing, as well as the Portable Test Controller. Based on input from customers at leading material, automotive and


aerospace test laboratories, it provides for efficient operation in an array of testing applications, including shock absorber tests, single-axis test systems, vibration and performance evaluation tests. Moog, Nieuw-Vennep, The Netherlands. Tel: +31 (0)25 246 2034. New motorized pendulum impact testing system for increased productivity and operator safety Available in capacities from 300 via 450, 600 and 750, up to 900 J, Instron’s newly developed MPX motorized pendulum impact testers are ideally designed for testing metals to Charpy and Izod standards. Thanks to their motor-driven raising of hammer with auto-return after test, all MPX systems are quick and easy to operate for increased productivity and operator safety. An electromagnetic brake/clutch control allows the hammer to be safely dropped, whilst its dual latch design prevents accidental release and a safety enclosure with interlocks prevents the hammer from dropping and stops movement when any door is open. An adjustable latch height allows for lower pendulum energy/velocity.

technology that provides a reliable solution for high frequency problems as well as full system vibro-acoustic evaluation. As acoustics takes more of a defining role in product development, vibroacoustic engineers need better tools to assess concepts and early stage designs. Unlike other methods, SEA does not require geometrical details, but merely global system properties. This is why SEA is ideal early in the concept phase when design details, like CAD or a FEM mesh, are not available. www.lmsintl.com PULS UK introduces life expectancy data logging to QS/QT 40 power supplies Leading Din Rail power supply manufacturer PULS UK has introduced data logging to its single-phase QS40 and three-phase QT40 1 kW units. The move will enable the company to establish life expectancy figures based on actual in service conditions.

Recent distribution agreement brings best-in-class Statistical Energy Analysis (SEA) technology to the world’s leading acoustic simulation package.

PULS uses semi conductor technology to collect data relating to operating temperature, input voltages and other vital information which can later be downloaded to calculate the life expectancy of the product. The company is also developing a version that can be downloaded externally allowing customers to monitor the condition of the power supply and schedule its replacement during normal maintenance programmes. PULS expects its new technology to be particularly effective in mission critical applications, such as oil and gas installations, where power failure could result in serious consequences for operators.

LMS International and InterAC have signed a strategic partnership to distribute InterAC’s SEA+, SEAVirt and related SEA modules to complement the market-leading LMS Virtual.Lab Acoustics package. In the world of vibro-acoustic simulation, SEA is a

Power supply manufacturers use MTBF (Mean Time Between Failure) procedures to estimate the life expectancy of their products using accepted industry figures; but PULS is the first to provide accurate information based on real-life operating conditions.

Instron Deutschland Pfungstadt, Germany. Tel: +44 (0) 6157 4029 600.

GmbH,

LMS-InterAC partnership completes the LMS Acoustic Simulation solutions to cover the full frequency range.

Toyohashi Tech researchers (Japan) develop magnonic crystal-based ultra-high sensitive magnetic fields sensors for monitoring heart and brain activity and room temperature High sensitivity magnetic sensors are important in medical diagnostics for applications such as monitoring heart and brain activities, where mapping distributions of localized extremely weak magnetic fields arising from these organs could provide early warning of life threatening diseases and malfunction. Mitsuteru Inoue and colleagues at Toyohashi University of Technology (Toyohashi Tech) have developed high sensitivity magnetic sensors using magnonic crystals—artificial magnetic crystal structures capable of controlling the propagation of magnetostatic waves. Magnonic crystals support the propagation of magnetostatic waves through the crystal spin system or suppress the propagation of waves due to the periodicity of the crystal structure. Contact: Ms. Junko Sugaya and Mr. Masashi Yamaguchi, International Affairs Division Tel: (+81) 0532-442042, E-mail:ryugaku@office.tut.ac.jp New Sidewinder(TM) reference design can provide a complete base station on a single PCB Cambridge Consultants, a leading design and development firm, has launched Sidewinder(TM), the smallest commercially available 2G and 3G small-cell platform. Ideal for use in mobile phone communications and professional radio, Sidewinder is software configurable between GSM/ GPRS/EDGE, WCDMA/HSPA+ and other SDR applications, providing new levels of adaptability for cellular base stations. It offers a low cost of entry for companies wishing to exploit these standards and sets a new benchmark in flexible, cost effective designs. Contact: +44 (0)208 408 8000.

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The Engineering Integrity Society is an independent charitable organisation, supported and sponsored by industry. The Society is committed to promoting events and publications, providing a forum for experienced engineers and new graduates to discuss current issues and new technologies. We aim for both company and personal development and to inspire newly qualified engineers to develop their chosen profession. Events run provide an ideal opportunity for engineers to meet others who operate in similar fields of activity over coffee and lunch. All of our events enable engineers to establish and renew an excellent ‘contact’ base while keeping up to date with new technology and developments in their field of interest. We are involved in a wide range of Industrial sectors including Automotive, Aerospace, Civil, Petrochemical etc and continue to be interested in new members from all sectors. None of the above can be done without your continued support! Act now and become an EIS Member today. Benefits: EIS members receive a subscription to ‘Engineering Integrity’, mailed direct to your office or private address. Discounts to EIS events. CDs with all the information the Society holds on file of presentations and overheads from conferences past to present. Plus access to Task Groups, to take part, or to receive information and recommendations. I would like to join the EIS for an annual fee of £25 I am already a Society member and would like to give the following additional amount to support the Society’s activities (Please specify amount) _____________ If you are a UK tax payer we are able to reclaim approximately 28% of your subscription if you check the box (Remember to notify us if you no longer pay an amount of income tax and/or capital gains tax equal to the tax we reclaim on your donations)

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Profile of Company Members Adept Scientific plc

MIRA Limited

Amor Way Letchworth Herts SG6 1ZA UK

Watling Street Nuneaton Warwickshire CV10 0TU UK

Tel: +44(0)1462 480055 Fax: +44(0)1642 480213 Website: www.adeptscience.co.uk

Tel: +44 (0)247 635 5000 Fax: +44 (0)247 635 8000 Email: enquiries@mira.co.uk Website: www.mira.co.uk Contact: Kristy Thompson, Marketing Manager

Adept Scientific is one of the world’s leading suppliers of software and hardware products for research, scientific, engineering and technical applications on desktop computers. Adept’s customer base includes world-leading technologybased manufacturing corporations, universities in the UK, Ireland, Germany and Denmark, small and medium-sized businesses, government departments, local authorities, hospitals, charities and NGOs. In the academic, business and technical world Adept Scientific is known for its efficiency and expertise in supplying solutions essential for customers’ business requirements, offering the highest level of support and back-up.

Millbrook Proving Ground Ltd Station Lane Millbrook Bedfordshire MK45 2JQ UK Tel: +44 (0)1525 404242 Fax: +44 (0)1525 403420 Email:neil.fulton@millbrook.co.uk Website:www.millbrook.co.uk Contact: Neil Fulton Millbrook is one of Europe’s leading locations for the development and demonstration of every type of land vehicle, from motorcycles and passenger cars to heavy commercial, military and off-road vehicles. Our custom-built facility provides virtually every test, validation and Homologation service necessary for today’s demanding programmes, complemented by a worldwide reputation for confidentiality, service and competitiveness. We also engineer, develop and build low-volume service vehicles, trial and evaluate vehicle capability, investigate inservice failures and provide specialist Driver Training.

MIRA is a highly customer-focused, world-class, independent vehicle engineering consultancy, shaping everything we do around the partnerships we create. We harness the skills, experience and knowledge of our talented experts to provide our customers with intelligent solutions to their challenging problems. MIRA offers full system design, test and integration expertise to the global automotive, defence, rail and transport industries. MIRA’s technical facilities provide a truly global centre of excellence from which to innovate, engineer, test and implement market changing solutions.

Research by the Younger Engineer Are you just starting out on an engineering career or currently studying for a postgraduate degree. Would you like to tell us about your research? What is the hot topic at the moment? We have many industrial readers who would be extremely interested in hearing about your research, both what it involves and its background. Articles of up to 850 words (approx 1 A4 page) can be published under our new ‘Research of the Younger Engineer’ in the journal, presenting a great opportunity to make industry aware of your work. Send your articles to the Editor: Dr Karen Perkins Materials Research Centre School of Engineering Swansea University SA2 8PP

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News on Smart Materials and Structures Welcome to our column on Smart Materials, with the usual mix between technical news and forthcoming evens in the field. The MEMS industry relies heavily upon rare-earth metals (Neodymium, Yttrium, Gadolinium for example). It is now a well know fact that 97 % of rare earth metals worldwide are produced in PR China, and this situation generates some concern about any possibility of monopolising the market (“Put all the eggs in a basket, but watch that basket”, as popular wisdom enunciates). A recent paper produced by a team from the University of Tokyo and published in Nature Geoscience (http:// www.nature.com/ngeo/journal/v4/ n8/full/ngeo1185.html) describes up to 78 sites, between 3000 and 6500 m below the South and North Pacific surface. These sites could provide up to one fifth of the world’s consumption of rare earth elements, definitely not a negligible percentage. There are some strong environmental concerns about mining rare earth minerals, both above and below the sea. However, considering the extremely strategic role that these metals invest in our t e c h n o l o g y, I w a n t e d t o g i v e a particular mention to this discovery. Something else that may be a future game-changer for systems and architectures for active control, embedded systems and model simulation is the new Intel Tri-gate chip (http://newsroom.intel.com/ docs/DOC-2032), which should allow to continue the validity of Moore’s law beyond the 22 nm and 14 nm processors (the latter currently considered as the limit for integration due to quantum mechanics effects). Although this transistor appears to have been designed essentially to cut a big

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slice of the market for tablets and smart phones (currently monopolised by ARM, a truly British success story), it is foreseeable that the use of the chip will have more than an application, from sensor systems with high throughput bus data rates to high-end design and simulation software tools. In the field of Structural Integrity, I would like to highlight the recent d e ve lo pment of an optical fibre corrosion sensor based on light reflection principles, and produced by a team from the University of Texas at Arlington. The design of the sensor is based on an optical fibre reflection device coupled to a tube/film sub-assembly, formed by welding a sacrificial metallic film to a steel tube. One side of the sacrificial metallic film is polished and isolated from the environment, while the opposite side is exposed to the corrosive environment. The corrosion pits erode the sacrificial film, and reduced the reflectivity of the polished surface, which is then detected by the fibre optics. The full description of this interesting sensor has been recently published in Smart Materials and Structures (IoP, http://iopscience.iop.org/0964 1726/20/8/085003/pdf/0964 1726_20_8_085003.pdf). Another recent interesting development generated by a team from Fraunhofer Institute and University Technical Darmstadt is the use of active piezoelectric patches to reduce crack propagation in aluminium plates (http://iopscience.iop.org/0964 1726/20/8/085009/pdf/0964 1726_20_8_085009.pdf). The main idea behind the concept is to lower the cyclic stress intensity factor near the tip of the crack using low voltage piezo actuators, decreasing therefore significantly the crack growth rate. The paper also describes a statistical analysis

made on several test layouts, and showing an average 20 % reduction of crack propagation in the various cases. A promising start for this concept, and a very good piece of work from the German team. We look now at a selection of incoming conferences in the area of smart materials and structures. For the audience interested in St r u c t u r a l H e a l t h M o n i t o r i n g a n important event this year will be SHM 2011 in Krakow (Poland: http:/ /en.shm2011.pl/). Embedded within the conference there will be a short c o u r s e o n St r u c t u r a l H e a l t h Monitoring with prestigious speakers of the field. Preparations are already underway for CIMTEC 2012 (4 th International Conference of Smart Materials and Systems, Montecatini (Italy: http:// w w w. c i m t e c - c o n g r e s s . o r g / 2 0 1 2 / general_outline.asp). The conference has several parallel sessions, and promises to be one of the true happenings of the season in the smart materials field. For people having the chance of travelling through India at the beginning of next year, the Indian Institute of Te c h n o l o g y of Bangalore organises the 6 th ISSS Conference (ISSS – 12: http:// isssonline.in/isss-2012), which is anticipated to be one of the major events in Asia next year. Closer to home is the ECCOMAS SMART’11 organised by Fraunhofer IZFP in Saarbrücken (Germany – URL at h t t p : / / w w w. i z f p . f r a u n h o f e r. d e / smart11/). Best wishes for a fruitful activity in the months to come. Fabrizio Scarpa Professor of Smart Materials and Structures, Bristol University


News from Formula Student Institution to host Air C a p t u r e Week to demonstrate key climate c h a n g e solution

T

h e Institution of Mechanical Engineers will be hosting “Air Capture Week” in October to raise a w a r e n e s s amon g s t t h e p u b l i c , policy makers and engineers of one of the most innovative emerging technologies in the fight against climate change. The week long series of events, which will start on 24 October, will feature an international summit of experts, workshops, discussions and debates, as well as a live public demonstration of air capture technology. The latter will be given by Professor Klaus Lackner from Columbia University in front of a London audience on the evening of 26 th October. By using air capture machines to remove CO2 from the air and then storing it underground, it creates negative emissions which help reduce the concentration of greenhouse gases in the atmosphere. CO2 captured by the devices could also be used for carbon recycling, where industries that require CO2 as a chemical feedstock for making products such as substitute fuels, source their CO2 from the atmosphere and thereby establish ‘closed’ loops for carbon. Air capture technologies currently provide a viable solution to historic emissions produced in the last century and difficult to manage emissions like those from

aviation,shipping and dispersed industries.

a big enough scale to make a difference.

Furthermore as international climate change negotiations stall these technologies buy the world time to get to grips with cutting emissions produced.

The Institution of Mechanical Engineers is calling on UK Government to:

Efforts to combat climate change have largely and rightly focused on mitigation – so cutting the amount of greenhouse gas emissions, particularly the CO2, we produce. While work must continue to reach a global agreement with ambitious cuts to emissions, there is also a real need for governments and industry to look at creative and ingenious ways of preventing climate change by tackling difficult emissions sources and taking out t h e g r e en hou se g ase s w e h ave already put in the atmosphere – essentially cleaning up air. As will be demonstrated during the Institution’s”Air Capture Week”, the technology to make these CO2 absorbing machines already exists, but government and businesses need to prioritise funding in these technologies to make them happen quickly and on

• support more detailed work to establish the cost of air capture technology and demonstrate its feasibility; • develop policy frameworks that enable the adoption of negative emissions and carbon recycling approaches to mitigation; and • provide international leadership on negative emissions and carbon recycling. With the lack of international progress in the mitigation of climate change, there is an urgent need for governments and businesses to fund technology development and to accept that air capture is a key part of the solution to the bigger climate change problem. Dr Tim Fox Head of Energy and Environment at the Institution of Mechanical Engineers

Diary of Events Instrumentation, Analysis and Testing Exhibition Tuesday, 6 March 2012 10:00 - 16:00 Silverstone Race Track International Exhibition Centre

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Challenge to Improve the Process from design to product This article is intended to stimulate a debate on a subject frequently discussed but rarely addressed. Within organisations each technology section is driven by its own objectives but the communication between sections is generally nobodies responsibility. Our process from design through prediction test and production needs to improve if we are to realise the demands of product improvement in shorter time and lower cost whilst ensuring product life and warranty. The challenge is to achieve the following targets and for Managements to accept the need for the required organisation to:1. Improve and validate predictive models. 2. Use simpler materials with lower manufacturing sensitivity. 3. Reduce test time and power consumed by 50%. 4. Maintain or increase product fatigue life. 5. Optimise and monitor manufacturing effects on fatigue. 6. Reduce time to market. Technologies used in the complete process appear to have become increasingly isolated and whilst they have improved their own process the transfer of data between has remained historic and limited. 1. Improve and validate predictive models Predictions often use inappropriate material data. Materials are now offered that suggest improved life but frequently suffer from the difficulty of maintaining their advantageous properties through the manufacturing process. The quality control material inspection generally only provides information based on static values of a sample which has not been stabilised and has unknown

34

residuals. Testing has shown that material from different suppliers all to the same specification and passed goods inward inspection had a difference in fatigue results of 5 to 1.

material can be significant. Flat steel sheet is bent straight to meet flatness specifications. This has the potential to create wide variation within the sheet of residual strain.

2. Use simpler materials with lower manufacturing sensitivity The manufacturing process is significant in creating the final material condition in the component and yet few if any measurements are made to identify manufacturing changes which control and improve component life. When components are formed and welded significant changes to these properties almost always take place. The degree of work done in the forming process and the distributed thermal changes in the welding process can result in significant residual strain variations.

When components are formed and welded significant changes to these properties almost always take place. The degree of work done in the forming process and the distributed thermal changes in the welding process can result in significant residual strain variations. Control and manipulation of induced residuals has shown 3 to 1 life improvement.

A 3 to 1 life variation caused by an uncontrolled cooling process after welding creating residual strain from thermal gradients. 3. Reduce test time and power consumed by 50% Frequently information provided for a test is a load profile to be applied. The anticipated deflections at the loading points should be provided but often are not. These deflections fix the flow, response and power requirements of the servo hydraulic actuators of the test rig. Often the limitations of the rig are not identified until the rig is built. With a complete set of initial information the rig limitations can be identified and addressed. Modifications to reduce test time and power and give a repeatable test with the available equipment can be proposed. Slowing down the fewer high velocity amplitudes and speeding up the many lower velocity amplitudes can significantly reduce test time whilst applying the same profiles. Test times are frequently reduced by a factor of 4 and in many cases a factor of 8. The test takes 12% to 25% of the original time and uses less power. 4. Maintain or increase product life Difference in residual strain in received

5. Optimise and reduce manufacturing effects of fatigue Test reports generally give arrangement definitions and life as a cycle count with details of failure location if appropriate. If no failure occurs little or no information is provided as to how much life was still in the component. It is generally an assumption that the test carried out did have the load distribution of the predictive model. Techniques are available which give 3 D strain distributions of the component under test providing overlay files for model validation. These show actual load path and real deflections. Huge differences between the predicted and achieved are apparent when unlike data is compared. Incorrect changes in design can result from this non validated process. 6. Reduce time to market By applying these techniques and continually updating and validating each stage of the process with real information significant changes can be made in time to market for a new product. It is important to develop the complete product process based on measured and improved data instead of a comparative evaluation based on previous units. Discussion The communication between technologies needs to be improved and techniques, which are available


News from British Standards BS 8888:2011 Later this year, a new revision of BS 8888 will appear, which will be the most significant update since the standard was first published in 2000. The year 2000 was when the British Standards Institution (BSI) withdrew BS 308, the UK’s national standard for engineering drawing, and adopted instead the international system for technical specifications which is defined in ISO standards. This international system for technical product specification is known as Geometrical Product Specification (ISO GPS). It is defined in a range of interlinked ISO standards, and has been adopted throughout Europe, and also by many other countries across the globe. In fact, the only alternative in widespread use is the American system of geometric dimensioning and tolerancing which is defined in the ASME Y14.5 standard. When the UK adopted the ISO GPS system, BSI also published a new standard, BS 8888, which was intended to ease and simplify the transition from BS 308 to the ISO GPS system. BS 8888 has since been revised and up-dated several times, to keep abreast of developments and changes within the ISO GPS system.

BS 8888 was always conceived of as a ‘signpost’ document, which would guide people through the ISO system, and provide some explanation about how to work with it. In large part it is an index, which is essential if users are to find information amongst the large number of ISO standards that constitute the ISO GPS system. Despite this, it is still often difficult to work with a system which is dispersed across a wide range of different standards, and although there is some structure to the way in which these documents are organised and interrelate, it is still somewhat haphazard in many areas. When this is coupled with the fact that the ISO GPS system is continuing to expand, with the development of many new capabilities for the definition of technical requirements, in ever increasing detail, there are clearly going to be challenges for anyone attempting to work with it. In an attempt to address these challenges, the next revision of BS 8888, due for publication towards the end of 2011, is going to incorporate a substantial amount of technical content which has been brought across from some of the key ISO standards. The aim is to provide the basic elements of technical product specification, and ISO GPS, in a single document. This will not replace the ISO standards, which will still be referenced from within the British Standard, and will provide more

extensive and more detailed content, but it should mean that the most fundamental elements of the system will be gathered together in a more accessible format. The document will be split into two sections, the first for Technical Product Documentation, and the second for Geometrical Product Specification. The first section will cover the manner in which information is presented, such as the layout of drawing sheets, projections, format of dimensions and tolerances, representation of features, etc. The second section will deal with how products are specified, with the use of datums, geometrical tolerances, surface texture requirements etc. At the time of writing this, an early draft is being published by BSI for public comment and feedback, although there is still further detail to be added, and some further changes to be made, before final publication. If you read this in time, you will be able to have a look at the draft document, and pass on any comments or feedback (BSI publishes draft standards for comment at http:// drafts.bsigroup.com/). Iain Macleod Iain Macleod Associates and Chair of BSI technical committee TDW/4/8 which is responsible for the maintenance and development of BS 8888.

Continued from previous page employed to control and validate each stage of the process. The global market demands less sophisticated and more economic controlled materials which are less vulnerable to the manufacturing process. Cost and time of each step of the process has to be reduced and our

predictive modelling capability improved by validation that include controlled production processes.

within one technology area as being their responsibility. I look forward to your comments.

The technologies are available and mature.

Norman Thornton Engineering Consultant

The problem is that there is no organisational responsibility for the improvement of information between technologies. Techniques are not seen

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“Open Access”, another instalment In the last issue of the Journal I contributed a column on Open Access technical information. I also promised a short series about large-scale changes which are taking place in publishing practices. Here is the second. The first article was about institution repositories, and how this has made a difference to accessing research information. Alongside these changes similar ones have been occurring in availability of teaching material. A development which was initially called Open Courseware (OCW), and is now usually called Open Educational Resources (OER), has made much teaching material freely available in all subjects. Downloading is immediate and copyright is usually a Creative Commons License. If you want to know more about this sort of License look up my article in this journal (reference below). Briefly it means that you can do what you like with the information as long as you say where it came from and don’t use it to earn money. You may not be involved in education, but some OER material may still be useful to you. For example, the UK Open University have released many of their courses under Creative Commons Licences, using the heading OpenLearn. They list 36 courses under Engineering and Technology, 29 under Computing and ICT, and 38 under Business and Management. I have known for some time that there was an OpenLearn course called “Finding Information in Engineering and Technology”. Recently I needed to read another one called “Finding Information in Business and Management”. As I started this article I had a closer look and discovered ‘Finding Information in’ Computing and ICT, Arts and History, Education, Health and Lifestyle, Modern Languages, Mathematics, Science and Nature, and Society. Many us spend time searching for information these days. Perhaps these free courses might be worth a look.

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All ten of the courses have the same framework, with bolted-on bits to suit each subject. You will probably be able to skip the starting questionnaire about how competent you are already. You will also know how to use keywords, but the section about how to systematically build a keyword list for a serious search may sharpen your performance. You probably use a general search engine like Google, but the courses list many more sources under various headings. Taking the Engineering and Technology one, the list is:

• • • • •

pleasant to read) Relevance (whether it is what you want) Objectivity (it should be objective, that is not biased) Method (how was the information obtained) Provenance (who published it, how qualified are they) Timeliness (is it old or recent)

There are about 200 words of text for each of the six points, giving guidance about what to look for.

Search engines; Google, Yahoo!, AltaVista, Ask.com, Google Scholar. Subject gateways (Directories) BUBL, Intute, TechExtra, Books and electronic books WorldCat. Databases ROUTES, Recent Advances in Manufacturing, TRIS Online. Images Arts and Humanities Data Service, British Library Picture Library. Journals Directory of Open Access Journals (plus some advice on general journal searching). Encyclopedias Wikipedia, Encarta. Patents Esp@cenet, UK Patents Office, World Intellectual Property Organisation. News sources EureaAlert, Abyz News Links

Information produced by searches will normally be stored on a hard disk. Your space on this disk will have your files, usually separated into folders or other divisions. Organising these so that you can get the one you want when you want it can be a problem. If you are using Microsoft Windows this has a ‘Find’ command, but this can be slow. The courses point out that a faster alternative is a desktop search tool such as:

A description is given of the characteristics of each source. At the end of the list is a section giving five questions to help you decide whether a particular source is right for your task.

Many other facilities are provided on a computer equipped for office use. Alerts can be set to give regular notice of new information, groups can be joined, RSS feeds can be used and so on. These are all described in the courses.

The modules I have used then go on to a section about checking whether the information found is of good quality. Most of us know that much of the information on the internet is unreliable. If reliability is important an approach called PROMPT is recommended. This suggests checking six qualities. These are: •

Presentation (is it easy and

• • • • •

Ask Copernic Google Desktop Windows Live Toolbar Yahoo! Desktop Search

These also offer more ways of organising the files.

Reference Sherratt, Frank “Free teaching information: what does it mean for companies?” Engineering Integrity, Vol. 21, March 2007, pp 26-30 Frank Sherratt, Engineering Consultant


Group News Simulation, Test & Measurement Group The Instrumentation Analysis and Testing Exhibition held at Silverstone in March this year drew an all time record high of exhibitors, attendees and income for the EIS. Against a backdrop of shrinking and cancelled exhibitions across the UK and across Europe, the EIS is clearly growing well and providing what the many other events lack. We are building on our success this year and, just as we outgrow the Jimmy Brown Centre at Silverstone, they kindly built us a massive new Exhibition area, which opened a few months ago. It will provide us far more space and maintains our now familiar view over the start-finish line – which was also moved. The Open Forum we held during the exhibition on 4 & 7 Poster testing attracted a guest panel covering production, military and motorsport speakers and attendees from wider industries still. Our particular thanks to Colin Dodds for chairing with his contagious humour, mixed perfectly with his own experience and knowledge. The single forum event will be increased and cover : KERS, Vision and Lasers, CAE Testing, Electric Actuation, Data Protocols, Acoustic Emission and Vehicle Simulators. If you have some sound experience and would like to be on the guest panel for any of these or even ask questions for the floor, we would love to hear from you. The whole exhibition will again be in early March (6th) and include a wide range of exhibitors, presentations, workshops and the forums, so it’s a useful day away from your PC’s and meetings. As always you are

guaranteed EIS hospitality, refreshments and will invariably meet up with many people you haven’t seen for a while. The STMG would like to thank Peter Blackmore for chairing the EIS for so many years. The EIS was recently described to me as the who’s-who in the world of Fatigue and Testing. To everyone who’s met him Peter clearly epitomises the uniqueness and quality of characters in the EIS. Conway Young Chairman

Sound & Vibration Product Perception Group The last event that the SVPP held was a one-day seminar on 29th March 2011 entitled ‘Low Carbon Transportation in New Sound Environments’. As with the previous event in Dec 2009, it was a joint event with Warwick Innovative Research Centre, held at their Digital Suite within the University of Warwick campus. Thanks to an outstanding effort by the committee, a very interesting programme was organised, including three presenters from Germany. Despite the challenging economic situation a total of 44 delegates attended, which met our expectation. One welcome addition was the attendance of two Warwick University student groups who show-cased their projects in the exhibition area, and attended some of the presentations. One of these groups showed their research on which type of sounds could

be emitted from EVs as pedestrian warnings, having developed their own sound synthesis software and hardware, which they demonstrated at the event using mobility scooters. The other group showed their work on an ultra light-weight speaker system using a foil laminate which can be formed to a shape suitable for mounting in a vehicle facia area. We were very pleased to have the student participation as it satisfies one of the key EIS objectives - to get young engineers engaged with EIS and its events. We will plan to do this again at the next event. The seminar finished with an expert panel session, where most of the presenters were joined by other experts to answer questions from the audience in the style of BBC ‘Question Time’. A very wide range of questions were put to the panel, ranging from emerging technology to new environmental legislation, and each member of the panel in turn gave their views. This has now become a regular feature of the SVPP events as it is not only highly informative (and entertaining!), but also seems to hold most of the delegates until a much later time of day (due to the quantity of good questions and comprehensive answers we actually finished at 5.00 even though timetabled for 4.30!). At some past events, people have started slipping away from midafternoon, which can leave a rather sparse lecture theatre for the concluding address! The committee is now in the early stages of planning the next one-day event to be held in early May 2012, once again a joint event with WIMRC at the their venue, and we expect soon to be publishing a call for papers on a topical sound and vibration product perception subject. John Wilkinson Chairman

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Committee members President: Peter Watson O.B.E. Acting Chairman Trevor Margereson, Engineering Consultant ............................................................................................... 07881 802410 Vice Chairman Robert Cawte, HBM United Kingdom .......................................................................................................... 0121 733 1837 Treasurer Khaled Owais, TRaC Environmental & Analysis .......................................................................................... 01926 478614 Company Secretary Robert Cawte, HBM United Kingdom .......................................................................................................... 0121 733 1837 EIS Secretariat Lisa Mansfield ............................................................................................................................................... 02476 730126 Communications Sub Committee – ‘Engineering Integrity’ Journal of the EIS Honorary Editor Karen Perkins, Swansea University ............................................................................................................. 01792 295666 Managing Editor Catherine Pinder ........................................................................................................................................... 07979 270998

Durability & Fatigue Group Chairman Robert Cawte, HBM United Kingdom .......................................................................................................... 0121 733 1837 Secretary Khaled Owais, TRaC Environmental & Analysis .......................................................................................... 01926 478614 Members John Atkinson, Sheffield Hallam University .................................................................................................. 0114 2252014 Martin Bache, Swansea University ................................................................................................................ 01792 295287 Peter Blackmore, Jaguar Land Rover ........................................................................................................... 01926 646757 Feargal Brennan, Cranfield University .......................................................................................................... 01234 758249 Emanuele Cannizzaro, Atkins Aerospace ..................................................................................................... 01454 284242 Amirebrahim Chahardehi, Cranfield University ............................................................................................ 01234 754631 John Draper, Safe Technology ..................................................................................................................... 0114 255 5919 Steve Hughes, Bodycote ............................................................................................................................... 01524 841070 Karl Johnson, Zwick Roell Group ................................................................................................................. 0777957 8913 Davood Sarchamy, British Aerospace Airbus ................................................................................................. 0117 936 861 Giora Shatil, Darwind ........................................................................................................................... +31 (0)30 6623987 Frank Sherratt, Engineering Consultant ....................................................................................................... 01788 832059 James Trainor, TRW Conekt Engineering Services ................................................................................... 0121 627 4244 John Yates, University of Sheffield ............................................................................................................... 0114 222 7748

Sound & Vibration Product Perception Group Acting Chairman John Wilkinson, Millbrook Proving Ground ................................................................................................... 01525 408239 Members Marco Ajovalasit, Brunel University ............................................................................................................... 01895 267 134 Alan Bennetts, Bay Systems ......................................................................................................................... 01458 860393 Dave Boast, Avon Rubber .............................................................................................................................. 01373 863064 Mark Burnett, MIRA ......................................................................................................................................... 02476 355329 Peter Clark, Proscon Environmental ............................................................................................................. 01489 891853 Gary Dunne, Jaguar Land Rover ................................................................................................................... 02476 206573

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Henrietta Howarth, Southampton University ................................................................................... 023 8059 4963/2277 Paul Jennings, Warwick University ..............................................................................................................02476 523646 Rick Johnson, Sound & Vibration Technology ............................................................................................. 01525 408502 Chris Knowles, JCB .................................................................................................................................... 01889 59 3900 Colin Mercer, Prosig ...................................................................................................................................... 01329 239925 Jon Richards, Honda UK ..............................................................................................................................01793 417238 Nick Pattie, Ford ....................................................................................................................................................................

Simulation, Test & Measurement Group Chairman Conway Young, Tiab .....................................................................................................................................01295 714046 Members Paul Armstrong, Amber Instruments ............................................................................................................. 01246 260250 Ian Bell, National Instruments ...................................................................................................................... 01635 572409 Steve Coe, Data Physics (UK) .......................................................................................................................01323 846464 Colin Dodds, Dodds & Associates ............................................................................................................... 07880 554590 Dave Ensor, MIRA .......................................................................................................................................... 02476 355295 Graham Hemmings, Engineering Consultant ............................................................................................ 0121 520 3838 Neil Hay, Napier University ........................................................................................................................... 0131 455 2200 Richard Hobson, Serco Technical & Assurance Services ............................................................................ 01332 263534 Trevor Margereson, Engineering Consultant ............................................................................................... 07881 802410 Ray Pountney, Engineering Consultant ........................................................................................................ 01245 320751 Tim Powell, MTS Systems ............................................................................................................................ 01285 648800 Mike Reeves, Engineering Consultant ......................................................................................................... 01189 691870 Gordon Reid, Engineering Consultant ......................................................................................................... 01634 230400 Nick Richardson, Servotest ...........................................................................................................................01784 274428 Paul Roberts, HBM United Kingdom ............................................................................................................ 0785 2945988 Jarek Rosinski, Transmission Dynamics .................................................................................................... 0191 5800058 Geoff Rowlands, Product Life Associates .................................................................................................... 01543 304233 Frank Sherratt, Engineering Consultant ....................................................................................................... 01788 832059 Bernard Steeples, Engineering Consultant .................................................................................................. 01621 828312 Marcus Teague, LDS Test & Measurement ................................................................................................. 01763 255 255 Norman Thornton, Engineering Consultant ................................................................................................. 07866 815200 Jeremy Yarnall, Consultant Engineer ........................................................................................................... 01332 875450

Sponsors The following companies are SPONSORS of the Engineering Integrity Society. We thank them for their continued support which helps the Society to run its wide-ranging events throughout the year. Adept Scientific

Millbrook Proving Ground

AWE Aldermaston

MIRA

Bruel & Kjaer

MOOG

Datron Technology

National Instruments

Doosan Babcock

Polytec

HBM United Kingdom

Rutherford Appleton Laboratory

Instron

ServoTest

Kemo

Techni Measure

Kistler Instrumemts

TRaC Environmental & Analysis

LMS UK

Transmissions Dynamics

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CPD dynamics 2012 SHORT COURSES Intensive short courses for engineers working in environmental testing and those concerned with design assurance, reliability and type approval testing, product development and screening.

VIBRATION TESTING 18 – 19 January 2012

CLIMATIC TESTING 15 – 16 February 2012

PRACTICAL SIGNAL PROCESSING 21 – 22 March 2012

MECHANICAL SHOCK TESTING 19 April 2012

Further information from:

Andy Tomlinson, CPD Dynamics Ltd.

andy@cpd-dynamics.co.uk www.cpd-dynamics.co.uk

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Engineering Integrity Issue 31