Research On Control System Of A New Spherical Underwater Vehicle

The new spherical underwater vehicle has advantages of compact design, good concealment and high flexibility. It can be applied in certain fields where other big vehicles cannot enter. It can also be used to ocean monitoring, offering communication relay and location service for the ships in the ocean.Firstly, in this thesis, structure, drive system and mechanical design of the designed spherical underwater vehicle are described, which provides an overall understanding of the new spherical underwater vehicle.Secondly, the hardware design of the spherical underwater vehicle control system is described in detail. Hardware circuit including the designed LM3S615 system board and DC motor driver board are mainly based on ARM CPU and AVR coprocessor. These two circuit boards communicate to each other through the I2C bus. LM3S615 system board connects itself with a computer and a MTI attitude sensor through two RS232 serial ports separately. The master chip LM3S615 processes data from attitude sensor, and commands ATmega16 to use PWM to control speed of the water spray motor in order to achieve such movements as going straight, turning left, turning right, acceleration, deceleration and stop.Thirdly, software program design and control algorithm research about the control system of the spherical underwater vehicle are carried out. The traditional PID control and the new Neural Network PID control are studied. At the same time, a real-time adjusting control method based on attitude sensor signal feedback is proposed. This method is easy for engineering applications, and it can be applied for objects and environmental uncertainty. Experiments prove that the real-time adjusting control method based on attitude sensor signal feedback is feasible, and can obtain a good expectant result. Software program designed for use mainly divided into two modules, namely, ARM-based C-language programming and AVR-based C-language programming, the design is in strict accordance with the data transmission format.Lastly, hardware testing experiments, external circuit experiments and underwater motion experiments based on spherical underwater vehicle are carried out, the experimental results are analyzed, and the results show that this thesis designed a successful spherical underwater vehicle, and the design achieved a good spherical underwater vehicle motion control.