基于串级PID的机器鱼位姿控制算法

针对三关节仿生机器鱼的位姿控制问题, 首先, 介绍三关节仿生机器鱼的硬件结构及其运动控制系统; 其次, 基于期望位姿建立坐标系, 构建机器鱼的位姿误差模型； 再次, 在串级比例-积分-微分(PID)控制系统的基础上, 提出基于串级PID的仿生机器鱼位姿控制算法; 最后, 在URWPGSim2D仿真平台和多水下机器人协作控制系统平台下分别进行算法仿真实验和实体实验. 实验结果表明: 与时变反馈控制算法相比, 基于串级PID算法的仿真机器鱼到达目标位姿所用时间增加, 但位置误差和方向角误差减小, 位姿控制的精度提高; 仿生机器鱼到达期望位姿所用时间为14.4 s, 位姿误差为(-3像素,-4像素,0.062 rad), 基本满足循迹和搬运等应用要求, 验证了算法的有效性.

Posture Control Algorithm of Robotic Fish Based on Cascade PID

Aiming at the posture control problem of three-joint biomimetic robotic fish, firstly, the hardware structure and motion control system of three-joint biomimetic robotic fish was introduced. Secondly, the coordinate system was established based on the expected posture to construct the posture error model of robotic fish. Thirdly, on the basis of cascade proportional-integral -differential (PID) control system, the posture control algorithm of biomimetic robotic fish based on cascade PID was proposed. Finally, the algorithm simulation experiment and the entity experiment were carried out on the URWPGSim2D simulation platform and the multi-underwater robots cooperative control system platform respectively. The experimental results show that, compared with the time-varying feedback control algorithm, the simulation robotic fish based on cascade PID algorithm takes longer to reach the target posture, but the position error and direction angle error decrease, which improves the accuracy of posture control. It takes 14.4 s for the biomimetic robot fish to reach the expected posture, and the posture error is (-3 px,-4 px,0.062 rad), which basically meets the application requirements such as tracking and handling, and verifies the effectiveness of the algorithm.