Prespecifiable fixed-time control for uncertain nonlinear system with input quantization

This paper focuses on the global prespecifiable fixed-time control problem of uncertain strict-feedback nonlinear system with input quantization. In contrast to the existing fixed-time control results, the signs of the control gains can be unknown in our paper. Unlike the traditional fixed-time control schemes, some exponential functions are added into the virtual controllers to accelerate the convergence rate. Besides, some dynamic switching functions are also introduced to compensate the unknown control signs. Based on the novel regulate law, the switching functions can be regulated online to ensure the fixed-time stability for the considered system. Furthermore, the settling time can be easily adjusted by selecting the controller parameters. Simulation results are provided to illustrate the effectiveness of the proposed control scheme.