LEICA DISTO D110
"Redesign Leica Disto D110 using Human Factors approach"
MSc Product Design Engineer
SAUMIL BHANDARI
TABLE OF CONTENT
. Introduction to Human Factors
. Product Analysis
. User Personas
. Usability Test Strategy
. Exploratory Test
. Insights & Prototype Improvement
. Comparative Testing
. Insights
. Improvement
. Insights & Improvement
. Assessment Test
. Insight & Improvement
. Summary of Issues
DELIVER
. Product . Interaction
References
EXECUTIVE SUMMARY
Following is the result of a 3 month project completed for the subject Human Factors while studying Product Design Engineering at Glasgow School of Art. The aim of the project was to research and analyze an existing product using the scientific discipline of Human Factors and accordingly propose design changes to the existing product. Each student had the option of choosing a product and the product I chose was a Leica D110 Laser Distance Measure. Leica d110 is currently the smallest laser distance measure in the market and is sold as an entry level product by Leica for Architects, Quantity Surveyors, Space Planners and DIYers.
My approach on this project has been more on the usability of the tool for the intended user. Through this project, I propose changes on the physical interface of the Leica D110. An important part of my redesign solution to the interface involves providing separate space allocation for the buttons which serve as 'MODES' for the user and the buttons which perform a 'FUNCTION'. This ideology is not very new and has been employed by various product companies to enhance the experience Human-Computer Interaction(HCI). The separate space allocation for a keyboard and mouse in a computer system is a fitting example. I thrive for simplicity in complex interfaces hence, my solutions provide the redesign of the existing product by changes that do not hinder the already existing manufacturing line and saves the company a lot of money hence works best in the present ecosystem of the company. An example is the introduction of printed ruler on the outer housing of the device. Anthropometric data for finger size of 95% percentile of population in Europe was used to decide 1.8 cm as the diameter of concave touch button for measuring.
My approach for this project has been equally scientific and creative keeping in mind the Human Factors ideology and methods. The basis of my changes to the existing design of Leica D110 have been the iterative Usability tests performed on real intended users of the product. Number of iterations have been performed using the models and prototypes made after each test to further refine the solution by identifying finer problems in usability of device. One of the solutions of not providing proper error feedback was actually first identified by the test user itself. The nature of usability tests conducted varied from exploratory tests to assessment tests to competitive tests depending on the stage of development. The ability to use different evaluative measures depending on the nature of tests has been a huge learning experience.
Lastly, to re-design a tool like Laser distance measure that then can be used to design other things has been a great experience under the guidance of my tutors at Glasgow School of Art.
Saumil Bhandari MSc Product Design Engineering
INTRODUCTION to HUMAN FACTORS
Human Factors is the study of how humans behave physically and psychologically while interacting with particular environments, products or services. This behaviour is influenced by sociological, economic as well as ideological factors unique to each individual. Hence, Human Factors incorporates within its discipline frameworks and tools which help the designer make sense of the complex information gathered from the human-technology interactions. The approach to the Human Factors studies is scientific in nature as the discipline relies heavily on analysis of user centred experiments using models and prototypes for suggesting appropriate design changes to the existing systems.
PRODUCT ANALYSIS
A laser distance measure is an electronic tape measure uses the laser technology to measure distance between two surfaces. Leica Disto D110 is an entry level laser distance measure used by professionals as well as DIYers. Typical applications include creating floor plans, quantity surveying among others.
Laser ON symbol
Previous reading
Measure/ Switch ON
Area Mode
Clear Screen/ Previous reading/Switch OFF Bluetooth
USER PROFILES
Data gathered from ethnographic interviews and observations was grouped into four categories that describe the personality of the user. Drawing from user persona framework described by Patrick W Jordan(3) qualitative data was grouped into four categories namely 'Physio-pleasure', 'Psycho-pleasure', 'Socio-pleasure', Ideo-pleasure'.
USABILITY TEST STRATEGY
Different stages of the process require different nature of testing. Since the project was an exercise in redesigning an existing product, Assessment tests will first be conducted to seek insights for further improvements. Improvements made will be prototyped and tested against the earlier versions. These phase of testing comes under Comparative test category which are ideally performed iteratively until the improvements are refined enough for high fidelity prototyping. Given the time-frame for this project, only one iteration will be performed. At-last, the higher fidelity prototypes will be tested against established benchmarks for validation.
ASSESSMENT TEST
ACTION
INTERACTION
Cardboardplastic packaging Pamphlets, mini-books
Wants to use the device
INTENTION
Wants to understand device usage
EXPERIENCE
How should I open it?
Excited about using the new device.
How do I assemble the packaging after unpacking?
Oh! Do I have to read all the manuals?
Why don't I learn by start using the device.
Batteries, Device, Pocket clip, Storage case
Laser alignment, Buttons, Feedback sound
Laser alignment, Buttons, Feedback sound, Posture
Wants to understand device usage
Subconsciously feel the psychological pleasure on hearing the clicking sound of part fitments during assembly.
Wants to understand device usage
Which button does what?
Why is it showing error?
I should know how to make measurements before going to a site
It might not be accurate
Use it to take actual measurement for door fitments
Ah! That is real quick as compared to measuring tape
What to press next?
LCD , Pen, Notebook
Memorize/record measurement for making a door
It shows exact reading up-to decimals as opposed to measuring tape.
EMOTION
positive negative
PROBLEM
The objective of the test was to evaluate user's experience of using the Leica Disto D110 by identifying pain points against quantifiable parameters like discoverability, usability and intuitiveness.
The test user is a door repair and fitment technician. He had a prior knowledge of a laser distance measure though he did not use one regularly.
The user was given a task scenario of measuring dimensions of door cavity for fitting a door. The environment for the test was a Lobby where the entry door had to be replaced. As a test monitor, I guided the user whenever it was required to make the test flow seamless.
Various questions asked after the test were used to evaluate user's experience against quantifiable parameters like discoverability, usability and intuitiveness. Since the test was qualitative in nature, observations were made into user's emotion while using the device. The test was recorded in a video format for later analysis.
The packaging unpacked with a various papers like license agreement, advertisement pamphlet. As a result the most important instruction manual was not easily distinguishable.
Once opened the packaging is clumsy to pack again and not suitable for storing all the important papers that came with it.
Hence, a simple, rugged packaging was designed with instruction graphics printed on the packaging itself.
COMPARATIVE TESTING
Old Packaging
New Packaging
A low fidelity cardboard prototype of the improved packaging was to be compared with the original packaging for usability and discoverability.
The test user was an employee of building maintenance and repair company.
The task was divided into two back to back sessions with the user opening the packaging, reading the manual, assembling the device and repacking the important papers. Similar task was performed for both the packaging followed by questionnaire session with the user.
The test was recorded in a video format for later analysis.
TASK ANALYSIS
Interaction between button press and LCD screens was analyzed by mapping all the LCD screens chronologically under each mode and functionality.
An important insight deciphered was that a long press led to change of mode from single measure mode to continuous measure mode whereas single press of area button led to area mode. This meant multiple interactions possible with 'ON/ MEASURE' button for measuring distance as well as for changing modes. Thus, non uniform interaction for changing modes led to few functionalities undiscovered by user. The red screens depict the problems LCD states on the Task analysis time line on the right.
IMPROVEMENT
FUNCTION
MODE
The usability of the device was divided in to modes and functions. Modes include continuous measure mode, single measure mode and area mode and bluetooth mode whereas the basic functions performed by the device are the measure and clear the reading.
Hence,Different buttons and interactions were associated with 'MODE' and 'FUNCTION'.
INSIGHT & IMPROVEMENT
Received Signal too low
Measuring time too long
Received Signal too high
Data Transfer Error
The target surface is partially reflective or too far away for accurate measurement.
Target surface is too close
Check bluetooth connection
To comprehend the error feedback the user needs to refer the manual for its correct meaning.
Simple intelligible error feedback needed to be displayed on LCD screens. The inbuilt bluetooth of the device communicates with mobile phone to display country specific language for the error feedback.
All the LCD screens possible under each mode and functionality was reproduced into a foam prototype. The user was asked to map each foam prototype to each task. This was done to test the improvements made.
ASSESSMENT TEST
The objective of the test is to validate the improvements made against set benchmarks for better usability.
The test user was a house painter technician. The task scenario was to carry out measurement of a wall to calculate the amount of paint needed for the wall.
User was asked to write a series of steps he would undertake to carryout the required task. Afterwards, each written task had to be assigned a unique foam prototype shown on the left.
INSIGHT & IMPROVEMENT
An important insight deciphered was that while measuring in uncomfortable situations as shown in the picture above the push button interface for measurement can disturb the alignment of device leading to inaccurate measurements. Secondly, laser distance measure way of measuring distances is an unintuitive way of measurement in contrast to using a measuring tape. A visual scale was printed on the outer form to allow for a sense of scale as well as intuitive orientation of the device.
Concave touch buttons Printed Scale
SUMMARY of ISSUES
PROBLEM
ACTION
Non - reusable packaging Too many instruction manuals
.Hidden Functions .Unintuitive measurement Poor Error Feedback
Open Packaging
Read the instruction manual
SOLUTION
Simple Rugged packaging
Basic instruction graphics on the packaging
Assemble the device
Measurement Trial Measure Record
. Different buttons for 'MODES' & 'FUNCTIONS'
. Printed Scale on outer form
Intelligible Feedback
DELIVER
BETTER ACCURACY
BETTER USABILITY BETTER INTERACTION
INTERACTION
The three different modes could be accessed using a spherical multi-state switch. Please note that the screen changes orientation to display mode and then switches back to horizontal orientation for measurement automatically.
INTERACTION
Once the mode is selected the two major functions namely 'taking measurement' and 'clearing the screen' can be performed using the concave touch button interface. Hence 'Modes' and 'Functions' have different interactions.
REFERENCES
1.Human Factors in Product Design: Current Practice and Future Trends
W. Green, Patrick W. Jordan
2.Understanding different types of Usability Tests Handbook of Usability Testing: How to Plan, Design, and Conduct Effective Tests
Jeffrey Rubin Dana Chisnell
3.Frameworks for User Profiles Designing Pleasurable Products: An Introduction to the New Human Factors, Patrick W. Jordan
4.Case Studies, Computer Interface design Designing Interactions
Bill Moggridge
5.Anthrometric data for 95 percentile finger size of man and women The Measure of Man and Woman: Human Factors in Design , Alvin R.Tilley, Henry Dreyfuss Associates
6.Details about other distance measures sold by Leica http://www.leica-geosystems.com/en/Leica-DISTO-D110_105308.htm 3/3/15 7:50 PM
7.Details about competitors . http://www.boschtools.com/Products/Tools/Pages/BoschProductDetail.aspx?pid=dlr130k
8.Technology used in Laser Distance Measure Master's Thesis - Design of Lidar-system, Department of Electrical and Information Technology Lund University Martin Andersson -mola.tf@gmail.com, Johan Kjörnsberg-johan.kjornsberg@gmail.com
9. PUGH MODEL evaluative measure http://cuba.coventry.ac.uk/maedesign/concept-design/l1-matrix-evaluation/ 20/4/2015 6:50 PM
