Yao Xuliang, Wang Xiaowei, Wang Feng, Zhang Le
College of Automation, Harbin Engineering University, Harbin 150001, China.
College of Mechanical engineering, Jiujiang Vocational and Technical College, Jiujiang 332007, China.
Sensors (Basel). 2020 Jan 31;20(3):795. doi: 10.3390/s20030795.
This paper studies three-dimensional (3D) straight line path following and obstacle avoidance control for an underactuated autonomous underwater vehicle (AUV) without lateral and vertical driving forces. Firstly, the expected angular velocities are designed by using two different methods in the kinematic controller. The first one is a traditional method based on Line-of-sight (LOS) guidance law, and the second one is an improved method based on model predictive control (MPC). At the same time, a penalty item is designed by using the obstacle information detected by onboard sensors, which can realize the real-time obstacle avoidance of the unknown obstacle. Then, in order to overcome the uncertainty of the dynamics model and the saturation of actual control input, the dynamic controller is designed by using sliding mode control (SMC) technology. Finally, in the simulation experiment, the performance of the improved control method is verified by comparison with two traditional control methods based on LOS guidance law. Since the constraint of an AUV's angular velocities are considered in MPC, simulation results show that the improved control method uses MPC, and SMC not only improves the tracking quality of the AUV when switching paths near the waypoints and realizes real-time obstacle avoidance but also effectively reduces the mean square error (MSE) and saturation rate of the rudder angle. Therefore, this control method is more conducive to the system stability and saves energy.
本文研究了一种无横向和垂直驱动力的欠驱动自主水下航行器（AUV）的三维（3D）直线路径跟踪与避障控制。首先，在运动控制器中采用两种不同方法设计期望角速度。第一种是基于视线（LOS）制导律的传统方法，第二种是基于模型预测控制（MPC）的改进方法。同时，利用车载传感器检测到的障碍信息设计一个惩罚项，可实现对未知障碍的实时避障。然后，为克服动力学模型的不确定性和实际控制输入的饱和问题，采用滑模控制（SMC）技术设计动态控制器。最后，在仿真实验中，通过与两种基于LOS制导律的传统控制方法比较，验证了改进控制方法的性能。由于MPC中考虑了AUV角速度的约束，仿真结果表明，采用MPC和SMC的改进控制方法不仅在航点附近切换路径时提高了AUV的跟踪质量并实现实时避障，而且有效降低了舵角的均方误差（MSE）和饱和率。因此，这种控制方法更有利于系统稳定并节省能量。
