Impact-aware humanoid robot motion generation with a quadratic optimization controller
This work addresses a specific problem for humanoid robotics by enabling more dynamic interactions, though it builds incrementally on existing continuous dynamics controllers.
The paper tackled the problem of enabling humanoid robots to perform impact-aware tasks with non-zero contact velocities, which was previously limited to near-zero velocities to avoid breaking contacts or falling. The result was a controller that allows robots to generate such velocities while satisfying hardware limits and stability constraints, without assumptions on impact location or timing.
Impact-aware tasks (i.e. on purpose impacts) are not handled in multi-objective whole body controllers of hu-manoid robots. This leads to the fact that a humanoid robot typically operates at near-zero velocity to interact with the external environment. We explicitly investigate the propagation of the impact-induced velocity and torque jumps along the structure linkage and propose a set of constraints that always satisfy the hardware limits, sustain already established contacts and the stability measure, i.e. the zero moment point condition. Without assumptions on the impact location or timing, our proposed controller enables humanoid robots to generate non-zero contact velocity without breaking the established contacts or falling. The novelty of our approach lies in building on existing continuous dynamics whole body multi-objective controller without the need of reset-maps or hybrid control.