Intro Design process iSprawl Stickybot Conclusion Spinybot 1 Bio-inspired robot design Sangbae Kim Biomimetic robotics Lab MIT
Dec 25, 2014
Intro Design process iSprawl Stickybot Conclusion Spinybot 1
Bio-inspired robot design
Sangbae Kim
Biomimetic robotics Lab MIT
Intro Design process iSprawl Stickybot Conclusion Spinybot 2
Outline • Vision • Design approach
– Bio-inspired design • iSprawl
– Hexapedal running robot
• Spinybot – Climbing robot using micro spines
• Stickybot – Gecko-inspired climbing robot with
Directional adhesives
• Conclusion & future work – Organic robotics
iSprawl
Spinybot
Stickybot
Intro Design process iSprawl Stickybot Conclusion Spinybot 3
Vision
• Mobile application • Unstructured/unexpected
environment • Compliant interaction
Biological inspiration
Bio-inspired robot design
Conventional robot design
• Grounded application • Structured/expected
environment • High-precision/speed position
control w/ stiff interaction
Intro Design process iSprawl Stickybot Conclusion Spinybot
Biological inspiration for locomotion?
4
Mechanical requirement
Biological requirement
Manufacturing
Energy source
Actuation
Control system
...
Grow
Eat
Evolve
Survive
Reproduce ...
Morphology
Energy exchange
Balance ...
Locomotion
Intro Design process iSprawl Stickybot Conclusion Spinybot 5
Passive compliance can replace the leg?
Oscar Pistorius
“Mechanical advantage”
1. 25% less energy expenditure
2. Nearly three times higher elastic energy recovery than human ankle
Photo: from dailymail.co.uk For limited tasks, passive mechanism may replace function of complicated system
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iSprawl - Power transmission system for Independent hexa pedal robot
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Biological Example for the Sprawl Robots
• Death-head cockroach Blaberus discoidalis – Fast (up to 10 body/s)
– Traverse rough terrain (up to obstacles 3X of hip height)
Blaberus discoidalis running over fractal terrain
(Full, et al., 1998)
Intro Design process iSprawl Stickybot Conclusion Spinybot 8
Functional Principles Learned from Biology
• Open loop control • Passive self-stabilization
– Compliant hips
• Thrusting legs • Differential leg function
(Sprawled Posture)
Active Thrusting
Force
Sprawled Posture
Primarily passive
trochanter- femur joint
(Full, et al., 1998)
(Full, et al., 1991)
(Garcia, et al., 2000, Meijer and Full 1999)
SLIP model
Intro Design process iSprawl Stickybot Conclusion Spinybot 9
Sprawlita
• Mass - .27 kg • Dimensions - 16x10x9
Leg length - 4.5 cm • Max. Speed 70+ cm/s
4+ body/sec • Hip height obstacle
traversal
Intro Design process iSprawl Stickybot Conclusion Spinybot 10
Flexible Power Transmission
Gear Motor
Slider
Flexible region (Arbitrary path)
Rigid region (Force output)
Rigid region (Force input)
Flexible cable
Flexible tube
Rigid Shaft Flexible Cable
Rigid Shell Flexible tube
Stroke length
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Rubber tube
spring
Rotational flexure with friction damper
Axial Leg Spring
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High speed camera
500 frames/sec Treadmill
Reflective Marker
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iSprawl Running
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Spinybot
• Length: 58cm
• Weight: 0.4 kg
• Motor pattern : fixed servo motor
• Battery: Lithume –polymer
• Gait: alternating tripod
• Developed with Alan Asbeck
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Climbing Experts Source of inspiration: geckos and insects
Photos: Mark Moffett
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Intro Design process iSprawl Stickybot Conclusion Spinybot 17
Stickybot
• Smooth wall climbing robot • Weight : 400g • Length : 38cm w/o tail • Actuation: 12 Servo motor • Highly underactuated leg and foot
design • Utilize Directional adhesive