针对水下机器人常规反步跟踪控制的速度跳变问题,提出了基于生物启发模型的反步滑模混合控制方法.应用生物启发模型的平滑、有界输出特性,产生渐变的参考跟踪速度,克服了速度跳变问题,也满足了推进器推力约束.同时自适应滑模控制算法产生跟踪控制律,对于水下干扰及模型不确定影响具有鲁棒性,能够实现水下机器人稳定、准确的轨迹跟踪控制.所提方法的稳定性通过Lyapunov理论进行了证明,并将该方法对FALCON开架水下机器人进行水平面离散轨迹跟踪控制的仿真研究,实验结果表明了提出控制方法的有效性.
To deal with the speed-jump in the conventional backsteepping tracking control for underwater vehicles, we propose a hybrid control combining the backstepping and the sliding-mode control based on the biological inspired model.Because of the smoothness and boundedness of the output from the bio-inspired model,this control produces a gradually varying reference tracking-speed for the underwater vehicles instead of a jumping reference tracking-speed which cannot be followed by the propeller thrust of underwater vehicles.An adaptive sliding-mode control algorithm is applied to generate the tracking control law which ensures the robust performance in the presence of underwater disturbance and model uncertainties to achieve the stable and accurate trajectory-tracking.The stability of the proposed method can be proved by Lyapunov theory.Finally,this control has been applied to simulate the horizontal discrete trajectory tracking-control on FALCON open-frame underwater vehicle.Experiment results validate the effectiveness of the proposed control method.