分析了7自由度冗余机械臂的运动学正逆解, 采用Denavit-Hartenberg(D-H)坐标法进行正运动学建模, 获得机械臂末端相对于基座的空间位姿; 采用位姿分离法进行逆运动学建模. 求位置逆解时, 由约束条件分别获得前4个关节角位移解析解; 求姿态逆解时, 采用欧拉角表示机械臂末端相对于基座的姿态, 减少了计算量. 以SCHUNK模块化7自由度机械臂为例,进行了运动学正逆解分析, 并基于虚拟样机进行了仿真验证.
The kinematics for a 7-DOF (degrees of freedom) redundant manipulator is analyzed. The Denavit-Hartenberg (D-H) method is used to analyze forward kinematics. Position and attitude of the end-effector with respect to the base are obtained. Attitude is separated from position in analyzing inverse kinematics. For the position inverse kinematics, angular-displacement of the former four joints is obtained under a constraint condition. For the attitude inverse kinematics, the Euler angles are used to describe attitude of the end-effector with respect to the base. This way, the calculation is reduced. For the modular 7-DOF manipulator produced by SCHUNK, kinematics is analyzed and verified by virtual prototyping simulation.
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