Novel humanoid push recovery using knee joint

Push recovery is one of the most challenging problems for the current humanoid robots. The importance of push recovery can be well observed in the real environment. The critical issue for a humanoid is to maintain and recover its balance against any disturbances. In this research two novel strategies have been devised to recover the balance of the humanoid which are called "knee strategy" and "knee-hip strategy". Also, a mathematical model validates the efficiency of the proposed strategies as demonstrated in the paper. Stable regions of proposed strategies illustrate that the humanoid can recover its stability in a robust manner. Experiments have been conducted on a humanoid robot and demonstrate that the proposed strategies can help the robot to recover the stability in the real environment.