Flexible Beam Robust H∞ Loop Shaping Controller Design Using Particle Swarm Optimization

In this paper a new strategy is proposed to design a fixed-structure robustcontroller for a flexible beam. Robust controller designed by the conventional H∞loop shaping method is not appropriate for a beam because of its high order andcomplicated form. Fixed-structure H∞ loop shaping control in conjunction withparticle swarm optimization (PSO)algorithm is used to overcome this drawback.The performance and robust stability conditions of the H∞ loop shaping controllerare formulated as the cost function in the optimization problem. PSO is adopted tooptimize the parameters and cost function. The proposed control design and H∞loop shaping method are successfully applied on the flexible beam, and results of thetwo approaches are compared. Simulation results show the superiorities of theproposed controller in terms of having a lower order and simple structure; besidesthe beam stability and robust performance are retained as well. Also in comparisonto the solutions based on genetic algorithms, the use of PSO shows better efficiencyin terms of computational time.

Keywords:

Fixed-structure , Robust controller , Flexible beam , H∞ loop shaping , Particle swarmoptimization