Floating Body Heading Control System Research

This paper researches on the heading control of floating body based on fuzzy control method. The floating body has an outboard machine as its power system, which is fixed on a rotating shaft, in order to produce thrust in the scope of 180 degrees in the horizontal plane, with similar functions of Z-propulsion.The whole control system is comprised of two subsystems, one is remote control system, which is mainly about a PC that charge on the display of Human-Computer Interaction interface; the another is the onboard DSP control system, used to operat the outboard machine. Data radio is used for the communication between the two subsystems.The whole control system alse has two control modes: manual and autocontrol mode. In manual control mode, the floating body is controlled by the operator, the onboard control system only execute the commands from remote control system and feedback the state information of the floating body; and in the autocontrol mode the operator only gives the heading information, the onboard control system will collect the position and posture information of the floating body and autocontrol the heading by the fuzzy control method.The onboard control system has a TMS320F2812 as its CPU to process most tasks, such as communication with the remote control system, feedback the state of the floating body and execute the commands send by the remote control system. The collected state informations such as lifting positon, petrol oil and so on, is used for the feedback of system controller and is sended to the remote control system to inform the operator. 8 channel UART ports were externed from the CPU by using 2 TL16C554 chips to fit the requirements of communication.The control method adopted is fuzzy look up table method. The input variables are the deviation of the heading of the floating body and its change rate; the output variables are the throttle and stall control volume of the outboard machine; and the control rules are set according to the module experiments and operating experience. By controlling the thrust produced by outboard machine, we try to control the heading of the floating body.At last, the procedure of the whole control system is designed, in which implemented the collecting of GPS/INS data and the state of outboard machine, the command decode, the look up table procedure for fuzzy control. Also some experiments were made, the experimental results prove that the designed control method can rightly output the throttle and stall control volume of the outboard machine.