Dynamic model analysis of a miniature robotic fish and its motion control based on integrated sensors

Recently, there has been an increasing interest in the motion, mechanism, and control of miniature robotic fish using smart actuators due to its efficiency and maneuverability. For a piezoelectric-driven miniature robotic fish, dynamic model of the dual-fin biological system was simulated, and sensors were integrated in the robot fish to measure its dynamic information and realized the motion control with DSP controller. A dynamics model around the structure and working principle of the robot fish was analyzed, and the relational mapping chain from the drive source to the motion of the fuselage was built. Then a lightweight inertial sensor module and a fin-integrated strain sensor were developed, to provide motion and force information of the robotic fish in real time. Especially, the motion state data measured by the inertial sensor is collected by DSP controller, and closed-loop motion control of the robotic fish was realized combining the PI control algorithm with the sensor's data as feedback information. This study verifies the effectiveness and feasibility of the proposed system with integrated sensors for the robotic fish and provides a theoretical and experimental basis for the development of miniature fish-imitating robots.