Legged Locomotion • Quick perspective on motors and gearing • Overview of interim design reports • Static stability of legged locomotions • Static walking robots • Dynamic walking • Legged locomotion in space flight U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 1 Chariot Wheel Suspension (JSC) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 2 Chariot Gearing System (JSC) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 3 Good Things Seen in Design Review • Name/acronym for rover • Explicit discussion of lunar vs. Earth rover • Trades on wheel diameter/width • Trades on 4 vs. 6 wheels • Wheel design details • Static and quasi-static stability • Power budgeting and battery requirements • Slope and turning stability analysis • Systems engineering (e.g., requirements, WBS) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 4 Things I’d like to see, but didn’t (yet) • Structure detail • Mass estimates (falling within limit with margin) • Center of gravity • Detailed overall CAD • Suspension dynamics • Alternative seat placement options • “Baseball card” single-slide summary • Complete crew systems design (e.g., ingress/ egress aids, restraints, controls, displays) • Innovation? U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 5 Things I’d Prefer Not to See • 3D plots for monotonic functions • Plots with unlabeled trend lines • Fonts too small to be read • Misspelled/misused “Ackermann” • Misspelled words in general U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 6 Beyond the Scope… • Umbilical handling is part of the BioBot package, which is payload, not rover – you need to allocate deck space to BioBot package and crew seat(s) and interfaces • U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 7 Legged Stability • Define the support region as the convex polyhedron formed by supporting leg tips (“feet”) • System is statically stable if gravitational force vector from CG passes through stability region U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 8 Wave Gait U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 9 Wave Gait U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 10 Wave Gait U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 11 Wave Gait U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 12 RHex - A Simple “Walking” Robot (CMU) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 13 RHEX Video U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 14 Frame-Walkers • Two fixed sets of legs creating fixed stability regions • Legs move past each other and keep CG in stable region • Can steer by rotating frames with respect to each other U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 15 Dante II Repelling Robot (CMU) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 16 AMBLER Characteristics U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 17 AMBLER Walking Gait U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 18 AMBLER Mechanisms U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 19 AMBLER Maintaining Even Orientation U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 20 Rappelling Robots - Free-Body Diagram U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 21 Leg Arrangement for Rappelling U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 22 LEMUR (JPL) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 23 LEMUR Leg Mechanism U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 24 LEMUR II U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 25 LEMUR II Walking Gait (Unstable) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 26 LEMUR II Walking Gait (stable) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 27 Leg-Wheel Hybrid System (MEL) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 28 SPIDER Prototype (JSC) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 29 SPIDER (JSC) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 30 SPIDER Leg Articulation U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 31 Honda P2 and P3 U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 32 Walking Truck (GM - 1968) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 33 ATHLETE (JPL) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 34 ATHLETE in Action U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 35 ATHLETE With Larger Legs U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 36 Desert RATS 2008 - Moses Lake, WA U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 37 Dynamic Stability for Legged Robots • Uses reaction forces on ground to maintain orientation • Similar to trotting and running gaits for animals U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 38 Hopping Robot Concept (Marc Raibert) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 39 Hopping Robot Motion Visualization U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 40 2D Hopping Robot (Marc Raibert) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 41 Spring Flamingo (MIT) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 42 Quadruped Robot (Mark Raibert) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 43 Big Dog (Boston Dynamics) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 44 ATLAS (Boston Dynamics) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 45 DARPA Robotics Challenge Fails U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 46 DARPA Robotics Challenge Clips U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 47 Next-Generation ATLAS Clips U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 48 Parcour Atlas (Boston Dynamic) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 49 Valkerie (NASA JSC) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 50 Valkyrie Overview Video U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 51 Robonaut 2 on ISS U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 52 Robonaut 2 Legs U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 53 Project M (NASA JSC) U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 54 Robonaut in Space: The Vision U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 55 Robonaut in Space: the Reality U N I V E R S I T Y O F Legged Locomotion Overview ENAE 788X - Planetary Surface Robotics MARYLAND 56.