The Research Of Robotfish-Explorer Based On Undulating Principle

Now underwater robot-explorers play an increasingly important role in the marine resources exploration. Most traditional underwater robot-explorers are driven by screw propeller, in which, however there're some limitations on efficiency, maneuverability, power consumption and etc. On the other hand, animals in the water such as cephalopod and fish have outstanding locomotion ability and high efficiency. So it is a very important to clarify how these animals locomote, which can be very useful in the development of a new type of high-efficiency underwater robot-explorer, which can be used in marine resources exploration and military affairs.The work of this dissertation focused on the prototype research of a cuttlefish based Robotfish-Explorer. In comparison with most fish-like-robots which are body and/or caudal fin(BCF) mode, the Robotfish- Explorer is developed on the basis of the undulatory locomotion of the cuttlefish's paired lateral fins which has much better maneuverability and motion stability and belongs to the median and/or paired fin(MPF) mode. It has the great advantages in not only pelagic swimming, but also in flexible swimming in a small area.In the dissertation, through the experiment and theoretical analysis, we managed to have on the cuttlefish locomotion, especially on its pair-fin's undulatory locomotion. From research, we have known that cuttlefish has high efficiency and maneuverability. Based on the bionic principle, an integrated prototype system has been developed to verify the feasibility and the performance of the mechanism we designed which mostly included flexible undulatory fin, direction control device, pitching control device and some other accessorial parts. In the project, The MCU MSP430F149 was employed for the control system. As a result, the prototype can be controlled by commands from RS232 serial port or remote controller. And through the simulation and design of the double PI control, we can control the rotate speed of DC servomotor very well. Then finishing the software based on C, it's used for the prototype control and communication. Finally, some experiments were performed and the results showed that our mechanical design and control system could work very well. The experimental results also gave some suggestion to optimize the design of the undulatory fin.The final goal of this study is to develop a novel type of underwater vehicles with good performances such as high efficiency, maneuverability, motion capability and so on, used in exploring the marine resources. The work we have done is just preliminary study, and further work is necessary in the future to improve mechanical design, motion control system, the motion capability and so on.