Selection and Designing of Command Shaper for Vibration Control of Flexible Manipulators: A Multi-objective Optimization Approach

Abstract

This paper presents a selection and design scheme of multimodal command shapers using the multi-objective genetic algorithm (MOGA). A control scheme comprised of a command shaper and a collocated proportionalderivative control is employed in order to reduce end-point vibration without sacrificing the system’s response speed. Command shaping causes a delay in the system’s response and, also, reduces system vibration and, in this manner, the amount of vibration reduction and the response delay conflict with each other. Conventional methods can hardly provide a solution that satisfies several design objectives demanded by practical applications due to the competing nature of these objectives. Furthermore, the selection of a shaping technique is crucial since robustness and computational complexity depend on the shaping technique. This paper proposes a combined approach to selecting and designing command shapers using MOGA. A comparative assessment of the performance of the proposed approach with the conventional single-objective and weighted-sum genetic algorithm optimization approaches is also provided. The proposed technique can provide a wide range of solutions in a single run to conflicting design objectives and satisfy associated goals.