Fig. 4 Rover extrusion sequence. Fig.1 Integrated design logic diagram 3.4 Support-Material Deposition Strategy Fig. 2 Construction process Fig. 3 Diagrammatic section of the construction method Fig. 4 Support material distribution for the column
Fig.1 Angle of repose table for granular materials DEPTH OF FOOTINGS - FOUNDATIONS (2012) Available at: http://www.abuildersengineer.com/2012/11/ depth-of-footings-foundations.html (Accessed: 2 November 2016).
Fig. 5 Support material distribution for the dome Fig. 6 Deposition sequence for two columns 3.2 Multi-Robot System Design Fig. 1 Proposed heterogeneous multi-robot system which includes a paste deposition rover (top-left), a support material dispensing rover (top-right), a stationary unit for material preparation (bottom-left) and an UAV equipped with an infrared sensor (bottom-right). Fig. 2 Multiple rovers work together towards the same goal. Fig. 3 An example of on-board sensing in which a light sensor is used to identify the material over which the rover is situated. Fig. 4 Comparison between global and local awareness.
3.5 Robotic Prototyping - Primary Deposition & Support Material Deposition Fig. 1 First sample was printed to calibrate the speed of the deposition and to test that the mixture keeps the coil shape. Fig. 2 Process pseudocode Fig. 3 The column was generated as an initial geometry for testing. Fig.4 Pneumatic extruder was used as an end-effector during the deposition process. Fig. 6 After the curing process is complied, support material has to be removed. Fig. 7 The part of the column that was printed during the Test 1 after the drying process.
Fig. 5 Stigmergic communication in which the 3D scan of a support heap generated by the ’s infrared sensor is used to define the rover’s locomotion routines.
Fig. 8 Simulation of column tool path execution with the industrial robotic arm KUKA KR-30
Fig. 6 Discretization of a 3D space into a 2D grid with obstructions.
Fig. 9 Deposition process of the column. Active printing time was 18 min.
Fig. 7 Grid-based approach with differential grid resolution.
Fig. 10 Column deposition process.
Fig. The five elements of cloud robotics. Goldberg, K. (2014) Robots with their heads in the clouds – aspen ideas. Available at: https://medium. com/aspen-ideas/robots-with-their-heads-in-the-cloudse88ac44def8a#.57xo0e596 (Accessed: 6 December 2016). Fig. 9 Device-user integration through the implementation of cloud robotics. 3.3 Primary Deposition Strategy Fig. 1 Transition from a linear extruded element to a massive extrusion. Fig. 2 Wall thickness differentiation enabled by the deposition strategy. Fig. 3 Linear displacement mechanism which makes it possible to execute the deposition strategy with a rover.
Fig. 11 Front view of the column that was printed during the Test 2 after the support material was removed. Fig. 12 Simulation of dome tool path execution with the industrial robotic arm KUKA KR-30. Fig. 13 Deposition process of the dome. Active printing time was 24 min. Fig. 14 Dome deposition process. Fig. 15 Top view of the dome after the deposition process was complied. Fig. 16 Front view of the dome that was printed during the Test 2 after the support material was removed. 3.7 Secondary Deposition Strategy Fig. 1 Secondary deposition pattern Fig. 2 Infrared sensor Kinect V.2
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