The pybullet simulation of RRP hopper based on the Raibert decoupled controller.
(Reference: https://github.com/YuXianYuan/Hopping-in-Three-Dimensions)
- Fixed the base. Selecting the joint PD gain for the FIGHT phase that can track the given foot trajectory (Add the damping gain on the P joint is recommended).
- Fixed the base on the vertical dimensional. Adding the thrust, and adjusting the stiffness gain of the P joint that keeps stable hopping.
- Without constrained. Setting a small body velocity gain, and adjusting the PD gain for body attitude control that keeps the body stable.
- Adjusting the body velocity gain that makes the body track the given velocity command.
Performances demo
Hopping speed up to 2m/s
In the case of hopping in place, resist the 0.5 roll/pitch disturbance
Horizontal velocity tracking accuracy ±0.2m/2
Body attitude change within 0.1 while hopping stability
Hard to track a low speed < 0.3m/s, because the body can not go through the neutral point and resulting in taking a step back
(Note: You can greatly improve the dynamic performance by adjusting the parameter)
Pinocchio - 2.6.3 https://github.com/stack-of-tasks/pinocchio
Pybullet - 3.1.7 https://pybullet.org/wordpress/
Shihao Feng