Worlds Within Worlds
Printing Functional Systems
Hod Lipson
Mechanical & Aerospace Engineering
Computing & Information Science
Cornell University
Cornell University
College of Engineering
Computational Synthesis Lab
http://ccsl.mae.cornell.edu
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
Threaded
Rod
~30V,
DC-10kHz
Linear
Motor
PIEZO-ACTUATOR
Material Fluid
Reservoir
Syringe
Barrel
Plunger
Material
Fluid
Reservoir
>250um
~100um
ol
To
Mo
n
tio
Deposition via Syringe Extruder Tool
Continuous paths
Volume Fill
o
To
lM
oti
on
Deposition via Ink-Jet
High-resolution patterning, mixing
Thin 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
Printed Active Materials
Some of our printed electromechanical / biological components: (a) elastic joint (b) zinc-air battery (c) metalalloy 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.
With Evan Malone
Zinc-Air Batteries
With Megan Berry
Zinc-Air Batteries
IPMC Actuators
IPMC: Ionomer
Ionomeric PolymerMetal 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 PolymerMetal 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
With Daniel Cohen, Larry Bonassar
Multi-material 3D Printer
CAT Scan
Direct 3D Print after 20 min.
Sterile Cartridge
Printed Agarose Meniscus
Cell Impregnated Alginate Hydrogel
Multicell print
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
Digital PDP-11, 1969
– Niche applications  Small demand
– Small demand  High cost
 Niche applications
Stratasys Vantage, 2005
Exponential Growth
RP Machine Sales
Source: Wohlers Associates, 2004 report
The Killer
App?
Honeywell’s
“kitchen Computer”
• Robust
• Low cost
• Hackable
Fab@Home
Precision: 25µm
Payload: 2Kg
Acceleration: 2g
Volume: 12”x12”x10”
Fab@Home
Fab@Home: “Fablab in a box”
www.FabAtHome.com
Digital Structures
Reconfigurable systems
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
Zykov, Mytilianos, Adams, Lipson Nature (2005)
Programmable Self Assembly
Stochastic 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
Real Time
With Paul White, Victor Zykov
500 µm
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
140
Unconstrained
Number of units
120
100
Square
80
60
40
H-Shape
20
Layered Square
0
0
2,000
4,000
6,000
Time
With David Erickson, Mike Tolley
8,000
10,000
Tile dimension: 500μm
With Mike Tolley, Davis Erickson
Randomized Machines
Tensegrity Robotics
Don Ingber, Scientific American 1998
Cytoskeleton of a mammalian cell
Particle Robotics
With Chandana Paul
Dictyostelium
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?