Inverse dynamics with optimal distribution of contact forces for the control of legged robots

In addition to well-thought mechanical designs, there is a need for advanced control algorithms that can provide the versatility needed to locomote on difficult, potentially extreme terrains. Such a controller should offer two important features: high tracking performance to guarantee precise feet and hand placements when needed and control of contact forces created by the robot on its environment. Contact forces play a very important role for locomotion on difficult terrain. For example, when the robot is walking on a slippery terrain the controller can minimize tangential contact forces to prevent slipping, or create specific contact forces to locomote on terrains that require close to climbing motions. In this presentation, we would like to discuss a new inverse dynamics controller that can guarantee both high tracking performances and an optimal control of contact forces at the same time [6]. The controller can dramatically improve the locomotion of robots on difficult terrains and is simple and robust enough to be used in fast control loops.

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