TY - GEN
T1 - Scalable Minimally Actuated Leg Extension Bipedal Walker Based on 3D Passive Dynamics
AU - Islam, Sharfin
AU - Carter, Kamal
AU - Yim, Justin
AU - Kyle, James
AU - Bergbreiter, Sarah
AU - Johnson, Aaron M.
N1 - Funding Information:
∗ Equal Contributors. This work was supported in part by the National Science Foundation under Grants IIS-1813920 and CCF-2030859 to the Computing Research Association for the CIFellows Project. 1Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA, [email protected] 2Department of Mechanical Engineering, Columbia University, New York, NY 10027, USA Fig. 1. A small (15cm leg length), minimally actuated, quasi-passive walker capable of walking and turning with open-loop control and a single actuator per leg. The nonconcentric foot curvature, hip position, and mass distribution are key to stable walking.
Publisher Copyright:
© 2022 IEEE.
PY - 2022
Y1 - 2022
N2 - We present simplified 2D dynamic models of the 3D, passive dynamic inspired walking gait of a physical quasi-passive walking robot. Quasi-passive walkers are robots that integrate passive walking principles and some form of actuation. Our ultimate goal is to better understand the dynamics of actuated walking in order to create miniature, untethered, bipedal walking robots. At these smaller scales there is limited space and power available, and so in this work we leverage the passive dynamics of walking to reduce the burden on the actuators and controllers. Prior quasi-passive walkers are much larger than our intended scale, have more complicated mechanical designs, and require more precise feedback control and/or learning algorithms. By leveraging the passive 3D dynamics, carefully designing the spherical feet, and changing the actuation scheme, we are able to produce a very simple 3D bipedal walking model that has a total of 5 rigid bodies and a single actuator per leg. Additionally, the model requires no feedback as each actuator is controlled by an open-loop sinusoidal profile. We validate this model in 2D simulations in which we measure the stability properties while varying the leg length/amplitude ratio, the frequency of actuation, and the spherical foot profile. These results are also validated experimentally on a 3D walking robot (15cm leg length) that implements the modeled walking dynamics. Finally, we experimentally investigate the ability to control the heading of the robot by changing the open-loop control parameters of the robot.
AB - We present simplified 2D dynamic models of the 3D, passive dynamic inspired walking gait of a physical quasi-passive walking robot. Quasi-passive walkers are robots that integrate passive walking principles and some form of actuation. Our ultimate goal is to better understand the dynamics of actuated walking in order to create miniature, untethered, bipedal walking robots. At these smaller scales there is limited space and power available, and so in this work we leverage the passive dynamics of walking to reduce the burden on the actuators and controllers. Prior quasi-passive walkers are much larger than our intended scale, have more complicated mechanical designs, and require more precise feedback control and/or learning algorithms. By leveraging the passive 3D dynamics, carefully designing the spherical feet, and changing the actuation scheme, we are able to produce a very simple 3D bipedal walking model that has a total of 5 rigid bodies and a single actuator per leg. Additionally, the model requires no feedback as each actuator is controlled by an open-loop sinusoidal profile. We validate this model in 2D simulations in which we measure the stability properties while varying the leg length/amplitude ratio, the frequency of actuation, and the spherical foot profile. These results are also validated experimentally on a 3D walking robot (15cm leg length) that implements the modeled walking dynamics. Finally, we experimentally investigate the ability to control the heading of the robot by changing the open-loop control parameters of the robot.
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U2 - 10.1109/ICRA46639.2022.9812053
DO - 10.1109/ICRA46639.2022.9812053
M3 - Conference contribution
AN - SCOPUS:85136333011
T3 - Proceedings - IEEE International Conference on Robotics and Automation
SP - 207
EP - 213
BT - 2022 IEEE International Conference on Robotics and Automation, ICRA 2022
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 39th IEEE International Conference on Robotics and Automation, ICRA 2022
Y2 - 23 May 2022 through 27 May 2022
ER -