全垫升气垫船PID-非奇异终端滑模的航迹保持

Trace-keeping Control of Air Cushion Vehicle based on PID- Nonsingular Terminal Sliding Mode Control

全垫升气垫船的操纵性较差,为使其在高速状态下能够准确的按设定航迹航行,设计了PID-非奇异终端滑模的航迹间接控制算法。外环的航迹引导采用PID控制,内环的航向跟踪采用非奇异终端滑模控制。利用滑模对非线性不确定性系统的强鲁棒性,弥补气垫船系数摄动问题,减小气垫船对外界干扰的敏感度。采用RBF神经网络辨识外界扰动来消除控制器抖振的影响,保持了滑模控制的强鲁棒性。仿真结果表明,在外界风干扰下,本文设计具有控制精度高、超调量小、稳定性好等特点,提高了气垫船的航迹保持能力。

A PID-nonsingular terminal sliding mode indirect control system, which is designed for enhancing the maneuverability and realizing the trace-keeping control accurately of air cushion vehicle(ACV) in high speed state is proposed in the paper. PID is introduced to design tracking guidance control which is outer loop. The nonsingular terminal sliding model control is researched for the course control that is inner loop. Sliding mode control as well known duce to its unique robust control performance for nonlinearity and uncertainty system. Then it is used to compensate for the uncertainties and reduce sensitivity to external disturbance of ACV. In order to reduce the chattering of the sliding mode control, a RBF neural network is introduced to approximate external disturbances to offset the disadvantages and guarantee robust performance. Under conditions of wind disturbances, the simulation results of the PID-nonsingular terminal sliding mode control system can achieve good stability and high precision.