Research On Walking Stability Of Biped Robot

To realize stable dynamic walking of biped robot is becoming one of the main focuses in robotics, it has not only important academic value but also considerable significance of application. The fine trajectory of walking is the theory base and key techniques to realize stable walking of biped robot effectively.We laid emphasis on algorithm design and simulation for dynamic walking motion planning. The dynamic trajectory of walking planning method based on ZMP (Zero Moment Point) has been discussed in detail.The main achievements of this text include:1. Research on kinematics and kinetics characters of the robot, direct kinematics model and inverse model of the robot are built based on generalized coordinates. By lagrange dynamic equations, the dynamic model of the simplified biped is given respectively in the period of single-foot support and double-foot support, and this model is easy to control.2. Aiming at the factors influencing the walking stability of biped robot, leading to the center of gravity and ZMP equation reflecting static stability and dynamic stability. After this the stable walking condition has being formulated.3. Due to the restrain in the course of robot's walking, designing a hip trajectory and an ankle trajectory in time variable. Then the motion of the other joints trajectory is calculated according to dynamic equation. The ZMP trajectory in the course of walking is determined by ZMP equation.4. Take X direction trajectory of hip joints as reference variable instead of time variable, thus the space location planning idea of the relating locomotion of the parts of the robot is consolidated. Based on starting point, ending point and the middle highest point, the tracks of the foot and hip joint are planned related to parameters through 3rd order spline interpolation. To infer space function of each joints combined with reverse motion rules of robots.5. Under the environment of matlab, we taken ZMP stable margin as evaluation function for searching in the scope, optimal trajectory has been gotten. The joint angles have been calculated by kinematics, to make sure the walking stability of biped robot.