Real-time joystick control and experiments of redundant manipulators using cosine-based velocity mapping

Abstract

In this paper, to achieve the real-time joystick control of redundant manipulators, two schemes are proposed and investigated: one scheme is a cosine-based position-to-velocity mapping, which maps the position of the joystick in the motion range to the velocity of the robot end-effector for the real-time end-effector velocity generation; and the other is a real-time joystick-controlled motion planning (JCMP) scheme, which is based on minimum-velocity-norm (MVN) and used to resolve the velocity-assigned inverse-kinematics problem of redundant manipulators. In addition, the JCMP scheme is formulated as a standard quadratic program (QP) subject to equality and bound constraints. For the purpose of experimentation, a numerical algorithm based on piecewise-linear equations (PLE) is developed for solving the resultant QP problem. Furthermore, the proposed schemes are implemented on the planar six degrees-of-freedom (six-DOF) motor-driven push-rod robot manipulator controlled by a joystick. Computer-simulation and experiment results validate the realization and effectiveness of such schemes and the numerical algorithm.