Shaking force minimization of high-speed robots via centre of mass acceleration control

Abstract

This paper deals with the problem of shaking force balancing of high-speed manipulators. The known solutions of this problem are carried out by an optimal redistribution of moving masses which allows the cancellation or the reduction of the variable loads on the manipulator frame. In this paper an innovative solution is developed which is based on the optimal control of the robot links centre of masses. Such a solution allows the reduction of the acceleration of the total mass centre of moving links and, consequently, the considerable reduction in the shaking forces. The efficiency of the suggested method is illustrated by the numerical simulations carried out for different trajectories: for examined planar two and three link serial manipulators the shaking force reduction reaches up to 77%. This approach is also a more appealing alternative to conventional balancing methods because it allows the reduction of the shaking force without counterweights. As a result, the input torques are also decreased, which is shown using dynamic simulation software.