Anti-interference and stable walking of biped robot based on a structured gait

Aiming at biped robot´s weak ability to resist interference in unpredictable environment, this paper proposes a closed-loop control system based on the structured gait. By a simplified model of biped robot, walking parameters such as step length, amplitude, frequency are included in a unified gait vector as well as step phase, and a structured gait is constructed. According to inverse kinematics, we can get all the joint´s locomotion trajectory of biped robot, including that of hip joint acquired from Numerical Optimization method whose optimum index is maximum ZMP stable region. Then, taking the coarse-grained trajectory of characteristic variables as the reference input of the closed control loop, walking parameter generator adjusts four parameters of structured gait vector by obtaining feedback from multiple sensors, and guarantees the robot´s stability. At last, we perform simulation experiments by exerting external force and placing obstacles, which illustrate that the biped walking based on structured gait method is more robust and stable.