李宗刚, 夏文卿, 葛立明, 杜亚江. 仿生机器鱼胸/尾鳍协同推进闭环深度控制[J]. 机器人, 2020, 42(1): 110-119. DOI: 10.13973/j.cnki.robot.190026
引用本文: 李宗刚, 夏文卿, 葛立明, 杜亚江. 仿生机器鱼胸/尾鳍协同推进闭环深度控制[J]. 机器人, 2020, 42(1): 110-119. DOI: 10.13973/j.cnki.robot.190026
LI Zonggang, XIA Wenqing, GE Liming, DU Yajiang. Closed Loop Depth Control of Biomimetic Robotic Fish Cooperatively Driven by Pectoral Fin and Caudal Fin[J]. ROBOT, 2020, 42(1): 110-119. DOI: 10.13973/j.cnki.robot.190026
Citation: LI Zonggang, XIA Wenqing, GE Liming, DU Yajiang. Closed Loop Depth Control of Biomimetic Robotic Fish Cooperatively Driven by Pectoral Fin and Caudal Fin[J]. ROBOT, 2020, 42(1): 110-119. DOI: 10.13973/j.cnki.robot.190026

仿生机器鱼胸/尾鳍协同推进闭环深度控制

Closed Loop Depth Control of Biomimetic Robotic Fish Cooperatively Driven by Pectoral Fin and Caudal Fin

  • 摘要: 为改善机器鱼定深控制过程中的动态性能与稳态性能,根据深度误差的大小将定深控制过程分解为趋近阶段与巡游阶段,给出了一种基于中枢模式发生器(central pattern generator,CPG)与模糊控制相结合的闭环运动控制方法.为此,首先建立了以压力传感器信号为反馈输入,通过模糊控制器调节控制参数的CPG运动控制模型.在此基础上,针对误差较大的趋近阶段,采用胸/尾鳍协同方式,通过趋近模糊控制器改变摇翼关节的偏置量与幅值来使机器鱼快速到达期望深度;针对误差较小的巡游阶段,采用改变攻角方式,通过巡游模糊控制器改变胸鳍攻角来使机器鱼保持在期望深度.两阶段之间通过胸鳍CPG的启停实现切换.模糊控制器设计时利用了基于最小二乘法对实验数据拟合而得出的俯仰角变化率与控制参数的近似关系,提高了机器鱼趋向期望深度的速度并减小了在期望深度巡游时的稳态误差.仿真与实验结果验证了所提控制方法的有效性.

     

    Abstract: To improve the dynamic and steady-state performance of robotic fish in depth control, the depth control process is divided into two stages named the approaching stage and the cruising stage according to the depth error, and then a closed-loop motion control method is presented by combining central pattern generator (CPG) and fuzzy control. Firstly, a motion control model based on CPG is established, in which the feedback inputs are the signals of pressure sensor and the control parameters are adjusted by fuzzy controller. On this basis, a cooperative driving mode of the pectoral fin and the caudal fin is employed for the approaching stage with large depth errors, and an approaching fuzzy controller is used to control the offset and amplitude of the feather joint such that the robotic fish can move to the desired depth rapidly. For the cruising stage with small depth error, a cruising fuzzy controller is employed to control the attack angle of the pectoral fin such that the robotic fish can cruise at the desired depth. The switch between those two stages is achieved by initiating and inhibiting the CPG of the pectoral fin. In the design of fuzzy controllers, the approximate relations between the control parameters and the changing rate of pitch angle obtained through fitting the experiment results by the least squares method, is utilized. So, the speed of the robotic fish moving to the desired depth is increased and the steady-state error when cruising at the desired depth is decreased. The validity of the proposed method is verified by the simulation and experiment results.

     

/

返回文章
返回