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Abstract This paper explores new ways to use energy shaping and regulation methods in walking systems to generate new passive-like gaits and dynamically transition between them. We recapitulate a control framework for Lagrangian hybrid systems, and show that regulating a state varying energy function is equivalent to applying energy shaping and regulating the system to a constant energy value. We then consider a simple one-dimensional hopping robot and show how energy shaping and regulation control can be used to generate and transition between nearly globally stable hopping limit cycles. The principles from this example are then applied on two canonical walking models, the spring loaded inverted pendulum (SLIP) and compass gait biped, to generate and transition between locomotive gaits. These examples show that piecewise jumps in control parameters can be used to achieve stable changes in desired gait characteristics dynamically/online.
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Impact-Free Gaits for Planar Bipeds: Changing Walking Speed and Gait
The problems of changing the walking speed and stride length of impact-free gaits for point-foot planar bipeds are addressed. The impact-free gaits are designed using an approach developed in prior work. It is shown that the impulse controlled Poincar´e map (ICPM) approach can be modified to transition between orbits defining gaits with different walking speeds, and the continuous controller can be changed during the swing phase to transition between gaits that have distinct stride lengths. The effectiveness of the approaches is demonstrated using simulations carried out on a five-link biped.
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- Award ID(s):
- 2043464
- PAR ID:
- 10559148
- Publisher / Repository:
- 2024 4th Modeling, Estimation and Control Conference
- Date Published:
- Subject(s) / Keyword(s):
- Path Planning and Motion Control, Robotics
- Format(s):
- Medium: X
- Location:
- Chicago, IL
- Sponsoring Org:
- National Science Foundation
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