1. A Compiler for Printable Robots
Ankur Mehta
PPR meeting
April 14, 2014

2. … in collaboration with
Daniela Rus
Erik Demaine, Marty Demaine
Byoungkwon An, Nicola Bezzo, Joe DelPreto, Peter Gebhard, Cindy Sung
Vincent Lee, Roger Lo, Ben Shaya
November 5, 2017
Ankur Mehta

3. Motivation
Allow non-experts to design and manufacture custom engineered robots
Employ inexpensive fabrication techniques
Simplify and streamline the design process
Enable rapid design iteration
Design a “robot compiler” to design printable electromechanical systems from specifications
November 5, 2017
Ankur Mehta

4. Robot compilers Vision: Big picture goal:
Autonomously co-generate mechanical, electrical, and software subsystem designs for personal robots
Big picture goal:
$ vim myrobot.rbt
“I want a robot to cook breakfast for me”
$ make myrobot
Parsing specification …done.
Determining behaviors …done.
Generating mechanisms …done.
Assembling components …done.
Printing …done.
Success!
November 5, 2017
Ankur Mehta

5. Let’s make some robots!
< video >
November 5, 2017
Ankur Mehta

6. Library of components Mechanical building blocks Mechanical assemblies
Electrical building blocks
Electromechanical mechanisms
November 5, 2017
Ankur Mehta

7. Library of components
November 5, 2017
Ankur Mehta

8. Hierarchical design
November 5, 2017
Ankur Mehta

9. Real world example
Request: “We need a robot with two rotating joints in series, rotating about the vertical axis. Each link is around 10cm. In ascii art form it is:
| | t
where | is a rotational axis, and t is the tool.”
“rotating joint”  ActuatedHinge
“link”  Beam
“the tool”  ActuatedGripper
November 5, 2017
Ankur Mehta

10. Database driven ecosystem
Composition
Generation
Python scripting engine
Python scripting engine
Parametrized component database
Other tools
ROSLab
2D / 3D CAD tools
MATLAB
Other tools
Robots!
Realization
Python scripting engine
Other tools
ROSLab
November 5, 2017
Ankur Mehta

11. Modular composition
User selects desired geometries with degrees of freedom and their ranges.
Standard user: assembles building blocks (GUI)
Expert user: can generate building blocks (Python)
November 5, 2017
Ankur Mehta

12. Robot creation process
< video >
November 5, 2017
Ankur Mehta

13. Component representation
{ Subcomponents }
Special case: EComponent
{ Parameters }
{ Connections }
Inherited by default
Can be altered by imposing constraints
Assembly instructions
November 5, 2017
Ankur Mehta

14. Mechanical representation
November 5, 2017
Ankur Mehta

15. Electronics - Hardware
Connect modules in chains
Unlimited number of devices
Devices easily distributed across robot
Easy to wire
Virtual pin numbers
Each device assigned a virtual pin
Users do not need to know about chain structure
Can view brain as giant microcontroller
Facilitates automatic composition
Facilitates auto-generation of software
November 5, 2017
Ankur Mehta

16. Electronics - Hardware
Modularize electrical system to mirror mechanical approach
Facilitates automatic layout and design
Electrical modules
Interface between brain and devices
Only need one signal wire – simplifies routing
3 general purpose inputs/outputs
Servos, LEDs, sensors, etc.
ATtiny Microcontroller
Code does not change based on attached devices or robot
November 5, 2017
Ankur Mehta

17. Electronics - Software
Android app automatically generates User Interface
Asks robot for description of devices via Bluetooth
Also includes graphical interfaces
User can wirelessly control robot without writing code
November 5, 2017
Ankur Mehta

18. Next steps
$ vim myrobot.rbt Come up with more robot ideas $ make myrobot Parsing specification …done. Determining behaviors …done. Define specification languages Translate between functional and structural specifications Generating mechanisms …done. Recommend mechanisms and parameters Assembling components …done. Automate component-level design decisions Optimize assembly Simulate and verify designs Printing …done. Expand fabrication capabilities Success!
November 5, 2017
Ankur Mehta