The determination of maximum endpoint tracking error due to uncompensated inertial payload dynamics is investigated. The problem is formulated on the basis of well-known kinetic and kinematic relationships with constraints on maximum joint positions and velocities as well as the generalized force/speed constraint relationship for each actuator. An endpoint tracking error objective function is formed, and numerical optimization is used to determine the maximum. An example computation is presented to show the tracking error under progressively increasing payload using a PUMA 560 manipulator with its first three joints in motion.>

Kinematic resolved-rate control is extended to the coordinated control of multiple robot arms cooperatively manipulating a single object. To provide the capability to control the forces applied to the jointly manipulated body and to the external environment, a force feedback loop is closed around the system. This results in a multiarm realization of the damping control method. The problem of redundancy in determining the distribution of loads among the manipulators is handled by minimizing a quadratic cost function in task-space force and torque. A coordinate system structure is described that permits manipulator control relative to a control reference frame which may be independent of the base coordinate systems of the respective manipulators and of the world reference system.>