Design of command shaper using gain-delay units and particle swarm optimisation for vibration control of a flexible system

Conventional command shaping method involves convolving a desired command with a sequence of impulses that may prove computationally expensive or unsuitable for a fast system. Moreover, a priori knowledge of the system parameters, such as resonance frequencies and associated damping ratios, is required to design the exact sequence of impulses to produce a command that results in zero residual vibration. A new command shaping method is proposed using gain and delay units to shape the reference input to reduce vibration of a flexible system. Assuming that, no prior information is available about the system, a new variant of particle swarm optimisation (PSO) algorithm is proposed and used to derive the gain values and the amount of delay. The effect of total number of delay and gain units is also analysed. A twin rotor system is used as the flexible system where the control strategy is applied and the results show the effectiveness of the proposed control strategy.