串联冗余自由度机构关节角位置的规划算法

Joint angle position planning approach for series redundant DOF mechanisms

为了建立一种实时求解串联冗余自由度机构关节角位置的方法,解决串联冗余自由度机构逆运动学求解中角位置的求解问题,给出了逆运动学的数值解。根据加权伪逆理论,采用瞬时最优速度表达关节空间角增量的方法,研究了关节空间角位置数值解法,给出了冗余自由度机构连续跟踪期望空间姿态时的关节空间角位置计算方法。在典型运动输入条件下,分别恒定速比关节位置算法和加权逆速度积分方法获得的关节位置和姿态误差进行仿真。为验证算法有效性,以卫星天线姿态稳定系统为研究对象,仿真结果表明,恒定速比关节位置算法在运动学逆解过程中能够保证天线姿态误差Frobenius(弗罗贝尼乌斯)范数小于10^(-4)。仿真结果表明:本文提出的方法能够连续给出冗余自由度机构运动过程中的关节空间角位置的希望值,实现了逆运动学角位置层面的数值解和理想的控制精度。

This paper proposes a method that can solve the joint angle position of a mechanism with series redundant DOFs in real time, solve the problem of attaining angular position in the inverse kinematics of the mechanism with series redundancy, and provide the numerical solution of inverse kinematics. According to weighted pseudo-inverse theory, this paper adopted the instantaneous optimum speed to represent the angle increment of joint space, studied the numerical solution of the joint space position, and presented the computing method for the joint spacers angle position as the redundant DOF mechanism tracks the desired space attitude continuously. Under typical motion in- put conditions, the joint position and attitude errors obtained by constant speed ratio joint position algorithm and weighted inverse velocity integral method were simulated. To verify the effectiveness of the algorithm, the satellite antenna attitude stabilization system was taken as the research target. Simulation results show that the constant speed ratio joint position algorithm can ensure that the attitude error of the antenna Fresenius norm is less than 10 -4 in the process of inverse kinematic solution. Simulation results show that the proposed method can give the desired value of joint space position continuously in the movement process of a mechanism with redundant DOFs. The nu- merical solution of the position of the inverse kinematics can be realized, and control precision is ideal.