Abstract:

When a humanoid robot walks in the environment, it will face many disturbances, including unknown external push, contact forces on the body, and impact ground reaction forces.

There are many unpredicted disturbance when a humanoid robot operates in a real environment. One of the most common disturbances is “push”. Different types of pushes should be handled with different strategies, and the strategy introduced in this thesis involves dealing with an external push from both the front and back of the robot in a sagittal direction.

The proposed COG angular momentum regulator effectively counteracts external forces and disturbances by generating motion of the upper body via using the CMP criterion and the ground reaction forces as feedback. Furthermore, the online COG and footstep planning strategy address two different types of pushes that are also introduced. The overall push recovery strategy developed in this thesis shows the successful recovery of the robot from a push state.