This paper presents a study on bioinspired closed-loop Central Pattern Generator (CPG) based control of a robot fish for obstacle avoidance and direction tracking. The biomimetic robot fish is made of a rigid head with a pair of pectoral fins, a wire-driven active body covered with soft skin, and a compliant tail. The CPG model consists of four input parameters: the flapping amplitude, the flapping angular velocity, the flapping offset, and the time ratio between the beat phase and the restore phase in flapping. The robot fish is equipped with three infrared sensors mounted on the left, front and right of the robot fish, as well as an inertial measurement unit, from which the surrounding obstacles and moving direction can be sensed. Based on these sensor signals, the closed-loop CPG-based control can drive the robot fish to avoid obstacles and to track designated directions. Four sets of experiments are presented, including avoiding a static obstacle, avoiding a moving obstacle, tracking a designated direction and tracking a designated direction with an obstacle in the path. The experiment results indicated that the presented control strategy worked well and the robot fish can accomplish the obstacle avoidance and direction tracking effectively.

本文提出了一种基于生物启发的闭环中央模式发生器（CPG）的机器人鱼控制技术，用于避障和方向跟踪。仿生机器人鱼由带有一对胸鳍的刚性头，覆盖有柔软皮肤的金属丝驱动主动体和顺应性尾巴制成。CPG模型由四个输入参数组成：拍打幅度，拍打角速度，拍打偏移以及拍打中拍打阶段与恢复阶段之间的时间比。机鱼具有在机鱼的左右两侧安装的三个红外传感器，以及一个惯性测量单元，可从中感应周围的障碍物和运动方向。根据这些传感器信号，基于CPG的闭环控制可以驱动机器人逃避障碍物并跟踪指定方向。提出了四组实验，包括避开静态障碍物，避开运动障碍物，跟踪指定方向以及在路径中带有障碍物的情况下跟踪指定方向。实验结果表明，所提出的控制策略效果良好，机器人鱼可以有效地完成避障和方向跟踪。