Vermelding onderdeel organisatie

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Recent Developments in Passive Dynamic Walking Robots

Seminar

May 13, 2005 University of Nottingham, UK

Laboratory for Engineering MechanicsFaculty of Mechanical Engineering

Arend L. SchwabGoogle: Arend Schwab [I’m Feeling Lucky]

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Acknowledgement

TUdelft:Martijn WisseJan van FrankenhuyzenRichard van der LindeFrans van der HelmJaap Meijaard… MSc students

Cornell University:Andy RuinaMariano GarciaMike Coleman

Insitu Group: Tad Mc Geer

Collins, S., Ruina, A., Tedrake, R. and Wisse, M., 2005. ``Efficient Bipeal Robots Based on Passive-Dynamic Walkers’’, Science 307: 1082-1085

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Contents

• Passive Dynamic Walkers• Passive Dynamic Robots• The Simplest Walker• Cyclic Motion; Stability & Basin of Attraction• Stability: Fore-Aft and Sideways• Conclusions

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Walking Robots-Anthropomorphic Design-Energy Efficient Ct=(energy used)/(weight*distance)=0.2

Museon 2001 Mike 2002 Max 2003 Denise 2004

Stappo 1995 Bob 2000 Baps 2001

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Passive Dynamic Walking

Wire Walker by G. T. Fallis Patented in 1888.

Wire Walker, Model 2002

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Simplest Walking Model

Scaling with: M, l and g and limit case: m/M -> 0

Leaves one free parameter:

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Walking Motion

Walking Motion in Phase Plane

nn

1

Cyclic Motion if

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Family of Stable Cyclic Solutions

Stability of Cyclic Motion Determined by Characteristic Multipliers ||<1 But How Stable?

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Basin of Attraction of Cyclic Motion

Cyclic Motion (Fixed Point) : )1561.0,1534.0(),(

Poincare Section

with basin of Attractionand failure modes:-falling Forward-falling Backward-Running

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Basin of Attraction (Cont’d)Basin of Attraction: askew & enlarged

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A few steps into the Basin of Attraction

x = Cyclic Motion

1 = Start

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Effect of the Slope on the BOA

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Simplest Walking Robot

Simplest Walker (1999): 2D, straight legs and point feetwalking down a shallow slope.(copy of the 1988 Tad McGeer walker)

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Bob: a Bipedal Robot based on Simulations

Bob (2000): 3D, Flat Feet, Knees and Ankle Actuation

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Robot with Knees, Round Feet, and Actuation

Mike (2002)

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For-Aft Stability or How to Keep from Falling ForwardSwing Leg Control:’’You will never fall forward if you put your swing leg fast enough

in front of your stance leg’’

Uncontrolled Swing Leg Control

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Adding an Upper Body

Max (2003) Bisecting Hip Mechanism

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Adding an Upper Body

Max 2003 On Level Ground Self-Starting

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Going into 3DSideway Stability by means of Lean-to-yaw Coupling

As in a Skateboard:

Velocity dependent Stability

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Going into 3DSideway Stability by means of Lean-to-yaw Coupling

Or as in a Bicycle:

Velocity dependent Stability

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Going into 3D: Denise

Bisecting Hip Mechanism

Tilted Ankle Joint

Lean-to-yaw Coupling

Upper Body

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Going into 3D: Denise

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Conclusions

Passive Dynamic Robots:

- use less control and less energy - walk more naturally.- help understand human walking.