本文主要研究两个平面三回转机器人操纵平面四连杆开链载荷的逆运动学和工作空间。首先，得到位置反问题的解，并用于研究固定在有效载荷连杆上的点的工作空间。这个问题的解是用运动学系数法求得的。该方法为机器人形成的闭合链的瞬时运动提供了有价值的几何洞察力。

THIS PAPER FOCUSES ON THE INVERSE KINEMATICS AND THE WORKSPACE OF TWO PLANAR THREE-REVOLUTE ROBOTS MANIPULATING A PLANAR FOUR-LINK OPEN-CHAIN PAYLOAD. FIRST, THE SOLUTION TO THE INVERSE POSITION PROBLEM IS OBTAINED AND USED TO STUDY THE WORKSPACE OF A POINT FIXED IN A LINK OF THE PAYLOAD. THE SOLUTION TO THIS PROBLEM IS OBTAINED USING THE METHOD OF KINEMATIC COEFFICIENTS. THIS METHOD PROVIDES VALUABLE GEOMETRIC INSIGHT INTO THE INSTANTANEOUS MOTION OF THE CLOSED CHAIN FORMED BY THE ROBOT.