Trajectory generation for kinematically connected multiple manipulators

This paper represents an algorithm for planning and generating the motions of visual sensor and manipulators that are kinematically connected. In this paper, KIST Humanoid robot is used for verifying the algorithm. This robot has a vision system and two robot arms, and they are mounted on a single robot body. Given a task to be performed, the robot arms need to generate a short path for arm with satisfying the conditions of robot posture and joint constraints. Simultaneously, the camera must be placed for optimal viewing conditions so the task progress can be monitored. Since their robots are kinematically connected, motion of arm robot interferes with the motion of camera and similarly camera motion affects the arm motion. For generating a path for desired motion regardless of other robot's motion, this paper use the robot's kinematic redundancy. From an inverse matrix of Jacobian, null matrix of redundant robot is constructed, and then the equations of motion of connected robot are induced for the case of following the fixed and moving target. For realize more human-like motion, problems are extended to the motion of 3 connected robots. For generating the concurrent motion of two arms and visual tracking, property of 'task-priority' and 'null motion generation by null matrix' is used and relating equations are obtained. From these results, graphic simulations are performed and verified.