四足机器人Trot步态偏航分析及其控制

Yaw Analysis and Control of Quadruped Robot in Trot Gait

为了解决四足机器人在对角小跑步态中存在的绕对角线翻转而导致在直线行走时出现偏航问题,在理论分析偏航现象的基础上提出一种姿态控制方法。首先建立四足机器人整体运动模型,通过数值分析和计算,得到偏航产生的根本原因:一是机体由于重力影响,会产生绕支撑对角线的翻转力矩;二是处于支撑相时,髋关节产生的反作用力矩,导致步态时序会提前或延后,引起绕机体对角线翻转。然后在此基础上,建立姿态控制模型,通过传感器测得偏航值,反方向补偿其偏航。最后进行动力学仿真实验,发现机器人在不加姿态控制的情况下,出现较大偏航值,而在应用姿态控制之后,偏航值得到了明显改善,仿真实验对比证明了该姿态控制方法有效地解决偏航问题。

In order to solve the yaw problem of quadruped robot when walking in a straight line due to turning around the diagonal in the diagonal trot gait,an attitude control method is proposed based on the theoretical analysis of yaw phenomenon.Firstly,the overall motion model of the quadruped robot is established.Through numerical analysis and calculation,the root causes of yaw are obtained:First,the body will produce overturning torque around the diagonal of support due to the influence of gravity;Second,in the supporting phase,the reaction torque generated by the hip joint will lead to the advance or delay of gait sequence,resulting in the reversal around the diagonal of the body.Then,on this basis,the attitude control model is established,the yaw value is measured by the sensor,and its yaw is compensated in the opposite direction.Finally,the dynamic simulation experiment shows that the robot has a large yaw value without attitude control,and the yaw value has been significantly improved after the application of attitude control.The comparison of simulation experiments shows that the attitude control method can effectively solve the yaw problem.