Joint asymptotic stability of robotic manipulators during compliant and free motion

摘要

In this paper the global asymptotic connective stability of robotic manipulators during contact with a compliant work environment is demonstrated. This result is shown for a general class of nonlinear control laws that approximately compensate for both the generalized forces that arise due to contact and the nonlinear coupling terms amongst the manipulator degrees of freedom. Additionally, the joint asymptotic connective stability of robot manipulators is demonstrated. It is shown that a single control law can guarantee the asymptotic connective stability of the robotic manipulator under the following conditions [i] free motion during which no contact is made by the manipulator on the work environment and [ii] compliant motion during which the manipulator end-effector is in contact with a compliant environment. It is shown that this stability result holds only for generalized contact forces that are small in magnitude, hence the stability result is local in nature. A detailed numerical example is provided to illustrate the application of the concepts discussed in the paper. Additionally, numerical simulation results demonstrate that the theoretical claims made in this paper hold for the example problem.