Dissociated jerk-limited trajectory applied to time-varying vibration reduction

Jerk-limited trajectories are a widespread solution for the trajectory planning of industrial machines-tools or robots. It is known that jerk limitation can reduce vibrations and in some cases can totally suppress residual vibration induced by a lightly damped stationary mode. However, for systems with time-varying mode, which is classically the case for configuration dependent mode or load mass variations, the previous result vanishes. This paper proposes to extend the jerk-limited profile (JL) properties to time-varying vibration problem. First, a guideline for designing a dissociated jerk-limited profile (DJL) based on simple and pragmatic Finite Impulse Response (FIR) filtering methodology is presented. Following the guideline, the time-varying vibration reduction principle is detailed. Then, experiments conducted on an industrial 3-axes Cartesian manipulator are presented. The experimental results show that the residual vibration magnitude is reduced to less than 23% of the original level obtained with JL profile and the settling time is reduced by 10%, demonstrating the efficiency of the proposed DJL trajectory planning. (C) 2012 Elsevier Ltd. All rights reserved.