The PSO Output Control Based On Backstepping Method

For the control problem of a class of strict feedback nonlinear uncertainsystems, the controller based on the backstepping method can get a good controlperformance. However, because of its structural characteristics, the controllerbased on the backstepping method also exists some defects such as large controlredundancy and system buffeting in the actual control. The particle swarmoptimization (PSO) aigorith has the strong stochastic parallel search capability,and is easy to understand and implement. In order to overcome the shortage ofthe general backstepping method and get the desired control performance, thispaper aims to combine the PSO aigorith with the backstepping method andconstruct the Lyapunov function to design the PSO controller based on thebackstepping method.First, for the control problem of the strict feedback nonlinear uncertainsystems, the basic principle of backstepping method is introduced. Then, thebackstepping controller of a concrete nonlinear uncertain system is designed tomeet the static and dynamic performances and make the tracking errorarbitrarily small; The defects of general backstepping method such as largecontrol redundancy and system buffeting are mentioned via the theoreticalanalysis.Second, the basic principles and characteristics of the particle swarmoptimization (PSO) algorithm are introduced briefly. The improved PSOalgorithm is obtained by combining the PSO with other optimization algorithms.Then, the improved PSO algorithm is used to tune the stabilization coefficientsof the backstepping controller online to overcome the blindness of thetraditional way to try and determine the calm coefficients.At last, the structure and work principle of the motion platform driven bythe rectangular sheet linear ultrasonic motor are introduced briefly and its nominal dynamic model is derivated on the basis of relevant knowledge.Acorrding to the system characteristics, the PSO controller based on thebackstepping method is designed to control the the motion platform driven bythe rectangular sheet linear ultrasonic motor. The fitness function is determinedby the backstepping method and the parameter adjustment rate of the PSO isobtained by the Lyapunov function. The stability of the control system is provedand the control effects and robust of the control system are verified through thesimulation.