基于七自由度(seven degrees of freedom, 7-DOF)机械手臂的结构和自运动特性,提出通过对关节位置进行几何分析，求解机械臂逆运动学的方法.该方法在自运动构型的基础上,以0坐标系为其他坐标系的基系,根据同一向量在不同坐标系之间的投影特性与关节角之间存在着的对应关系，实现对七自由度机械臂逆运动学的求解.该方法能够求解出针对任一特定末端位姿的所有理论逆解.通过引入机械臂优化的二次目标，对所有理论逆解进行优化，可得最优逆解用于机械臂控制.与梯度投影法等通用算法相比，该方法具有直观简练、计算量小等优点,且不同的末端位姿求解过程互不影响，对系列性末端位姿连续求解不存在累积误差.
Based on the structure of a robot manipulator with seven degrees of freedom (7-DOF) and its self-motion characteristic, a geometric method is proposed to find solution of inverse-kinematics of a robot. The algorithm is at the level of position for inverse kinematics. Self-motion of the redundant manipulator is described and used to solve inverse kinematics of the redundant manipulator. The inverse-kinematics is solved using its self-motion. Computation involved in the method is easy. It is efficient in solving the inverse kinematics.
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