Printing Functional Systems
Hod LipsonMechanical & Aerospace Engineering
Computing & Information ScienceCornell University
Computational Synthesis Labhttp://ccsl.mae.cornell.edu
Cornell UniversityCollege of Engineering
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Adaptation
• Changing environments, tasks, internal structures – Behavioral adaptation– Morphological adaptation
Breeding machines in simulation
Lipson & Pollack, Nature 406, 2000
Emergent Self-Model
Bongrad, Zykov, Lipson (2006) Science, in press
Damage Recovery
With Josh Bongard and Victor Zykov
Making Morphological Changes in Reality
Printable Machines
Multi-material processes
LinearMotor
ThreadedRod
SyringeBarrel Plunger
Deposition via Syringe Extruder Tool
>250um
MaterialFluid
Reservoir
PIEZO-ACTUATOR
Material FluidReservoir
~30V,DC-10kHz
Deposition via Ink-Jet
~100um
Continuous pathsVolume Fill
High-resolution patterning, mixingThin films (60nm)
Multi-material RP
Illustration: Bryan Christie
Our RP Platform
Fabrication platform: (a) Gantry robot for deposition, and articulated robot for tool changing, (b) continues wire-feed tool (ABS, alloys), (c) Cartridge/syringe tool
Some of our printed electromechanical / biological components: (a) elastic joint (b) zinc-air battery (c) metal-alloy wires, (d) IPMC actuator, (e) polymer field-effect transistor, (f) thermoplastic and elastomer parts, (g) cartilage cell-seeded implant in shape of sheep meniscus from CT scan.
Printed Active Materials
With Evan Malone
Zinc-Air Batteries
With Megan Berry
Zinc-Air Batteries
IPMC Actuators
IPMC: Ionomer
Ionomeric Polymer-Metal Composite
• “Ionic polymer”• Branched PTFE
polymer• Anion-terminated
branches.• Small cation
First printed dry actuator
• Quantitative characterization
• Improve service life– Reduce solvent
loss– Reduce internal
shorting
• Improve force output, actuation speed
Embedded Strain Gages
Silver-doped silicon
Robot finger sensor
IPMC: Ionomer
Ionomeric Polymer-Metal Composite
• “Ionic polymer”• Branched PTFE
polymer• Anion-terminated
branches.• Small cation
First printed dry actuator
• Quantitative characterization
• Improve service life– Reduce solvent
loss– Reduce internal
shorting
• Improve force output, actuation speed
IPMC Actuators
ResultsPower [W]
Force [mN]
100% Printable Robot
Printed Agarose MeniscusCell Impregnated Alginate Hydrogel
CAT Scan
Direct 3D Print after 20 min.Sterile Cartridge
Multi-material 3D Printer
Multicell print
With Daniel Cohen, Larry Bonassar
The potential of RP
• Physical model in hours
• Small batch manufacturing
• New design space
• Design, make, deliver and consume products
• Freedom to create
Learning from the history
• Similarity with the computer industry– In the ’50s-’60s computers…
• Cost hundreds of thousands of $• Had the size of a refrigerator• Took hours to complete a single job• Required trained personal to operate• Were fragile and difficult to maintain
• Vicious circle– Niche applications Small demand– Small demand High cost
Niche applications
Digital PDP-11, 1969
Stratasys Vantage, 2005
Exponential Growth
Source: Wohlers Associates, 2004 report
RP Machine Sales
The Killer App?
Honeywell’s “kitchen Computer”
• Robust
• Low cost
• Hackable
Precision: 25µmPayload: 2KgAcceleration: 2gVolume: 12”x12”x10”
Fab@Home
Fab@Home
Fab@Home: “Fablab in a box”
www.FabAtHome.com
Digital Structures
Reconfigurable systems
Zykov, Mytilianos, Adams, Lipson Nature (2005)
• Fukuda et al: CEBOT, 1988
• Yim et al: PolyBot, 2000
• Chiang and Chirikjian, 1993
• Rus et al, 1998, 2001
Murata et al: Fracta, 1994
Murata et al, 2000
Jørgensen et al: ATRON, 2004
Støy et al: CONRO, 1999
Programmable Self AssemblyStochastic Systems:
scale in size, limited complexity
Whitesides et al, 1998
Winfree et al, 1998
Saul Griffith, Nature 2005
Hardware implementation: 2D
White, Kopanski & Lipson, ICRA 2004
Implementation 1: Magnetic Bonding
With Paul White, Victor Zykov
Construction Sequence
High Pressure
Low Pressure
Construction Sequence
Construction Sequence
Construction Sequence
Construction Sequence
Construction Sequence
Reconfiguration Sequence
Reconfiguration Sequence
Implementation 2: Fluidic Bonding
Accelerated x16
With Paul White, Victor Zykov
Real Time
With David Erickson, Mike Tolley
a) t = 18.8 s b) t = 19.3 s c) t = 19.5 s d) t = 19.7 s
e) t = 4.9 s f) t = 8.6 s g) t = 14.3s h) t = 15.6s Figure 5. Assembly and Disassembly of 500 μm Silicon Tiles on PDMS Substrate
500 µm
With Mike Tolley, Davis Erickson
Tile dimension: 500μm
Randomized Machines
Dictyostelium Cytoskeleton of a mammalian cellDon Ingber, Scientific American 1998 With Chandana Paul
Particle RoboticsTensegrity Robotics
Grand Challenges
• Can we design machines that can design other machines?
• Can we make machines that can make other machines?
• Can we make machines that can explain other machines?