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Programmable Matterwith Modular Robots

Daniela RusCSAIL, MIT

Z. Butler, P. Corke, C. Detweiler, B. Donald, K. Gilpin, K. Kotay,C. Levey, I. Paprotny, I. Vasilescu, M. Vona, Y. Yoon

Motivation

Fixed architecture robot = fixed task set Flexible architecture robot = versatility

•Multiple locomotion gaits•Multiple manipulation gaits•Self-assembly•Self-repair

How do living cells differentiate? •Synthetic engineering exploration

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Self-reconfiguring Robots

blob

snake

slinky

•Multiple modules•Physically connected•Capable of autonomousstructural change•Multiple functionalities---form follows function

Programming matter byself-reconfiguration

All modules identical/active Connections Actuation by rotation, sliding, scaling Local communication

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Programming Matter Example:The Molecule

2 atoms, 1 bond, 5 connectors/atom 4 rotational degrees of freedom 4 Futaba S9204 10 Micro Mo motors FDM fabrication

Programming Matter Example

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Programming Matter:Distributed Control

Abstract model of relative motion: cubeSynthesize task-specific local rules (manually or learning)Prove correctnessCompile to specific hardware actuation

Programming Matter:Distributed Locomotion

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Programming MatterDistributed Control Analysis

Correctness: Some rule can always be applied Eastward motion results form all possible

sequences of rule activations The robot remains connected

Obstacle field must be shorter than therobot

Programming Matter:Another WayProof outline1. A rule can always be applied2. Rule applications Þ east movement3. The cell array remains connected

Graph equivalence1. No leaves2. Cycles : eastward displacement3. Nodes are connected cell arrays Automated proofs can be produced

for a given rule set and cell array

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Programming Matterby Disassembly

Initial configuration Finished product

Self-assembly as Sculpting

Programming Matter byDisassembly Trade-offs Simple actuation

mechanism fordisconnection

Disconnectioneasier, faster, morerobust than makingconnections

Gravity pullsmodules away

Must start from pre-assembled structure

Must rely onexternal force fordiscarding modules(gravity)

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Programming Matterby Disassembly Example

Motor

Magnet Assembly

“Switchable” Magnet

Li-PolyBatteries

Tilt Sensor

IR PhotodiodeIR LED

ARM Processor

2-D Accelerometer

Hall Effect Sensor

Miche Module

Programming MatterSelf-disassembly Algorithm

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Programming Matter Self-Disassembly Execution

5 trials, 120 secs average completion, some units can’t fall

Programming MatterLocalization with Tokens

Idea: each module computes a relative coordinateBenefits: global structure not known/needed

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Programming Matter Shape Distribution

Idea: included modules only receive message along shortest pathBenefits: no global knowledge/need of shape

Programming Matter:Self-disassembly Example

15 trials, 90 secs average completion

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What Types of Modular Robots?

Spectrum of capabilities: Self-reconfiguring: Actuation, Connection,

Computation, Sensing, Communication Self-disassembling: Connection, Computation, Sensing,

Communication Computation, Sensing, Communication Computation and Communication Inert

Spectrum of sizes: Large to Tiny Robots Spectrum of applications: ground, water, space

Programming Matterwith Microrobots

Untethered actuators Self-release Power-delivery

With B. Donald

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Programming Matter with Microrobots

Plate length: 80 microns; width 2 microns; speed 1.5 mm/sec

Programming Matter withRobots and Passive Blocks

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Programming Matterwith Robots and Passive Blocks

Programming MatterUnderwater

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Summary

Modular robots as alternative to fixedarchitecture robots

A spectrum of capabilities for modules The future:

BioChemical+Electromechanical Robotics(Wet+Dry)

Distributed control of millions of tiny modules

Questions