Fuzzy-PID control for the position loop of aerial inertially stabilized platform

摘要

Due to multiple-source disturbances, frame dynamic characteristics of aerial inertially stabilized platform (ISP) changes, leading to nonlinear and time-varying position loop error. Therefore, conventional PID control with fixed parameters can't bring performance of high accuracy and fast response. In this paper, control strategy that sets K_d at a certain value, and adjusts K_p and K_i in real time is proposed. Meanwhile, a fuzzy-PID controller selecting position loop error and its changing rate as observed value is designed with online modification of proportion and integration parameters. The principle prototype of aerial ISP made by our research group helps to conduct static leveling and dynamic vehicle experiments. The results indicate that overall performance of the platform is improved much for the reason that compared with conventional PID control, the fuzzy-PID control brings faster leveling speed and better steady precision.