Design of the multi-tasks multi-processors system for an underwater robot

An underwater robot is widely used in many industries. The posture control of the robot is important since it makes a robot able to move in hard environment with stability and achieve precise motion following the desired trajectories. The designed underwater robot consists of 8 custom made thrusters in order control all robot state variables and make the motion achieve 6 Degrees-Of-Freedom. Robot hardware is separated into several hulls. Multi-processors design is implemented for robot hardware because it reduces complexity of wiring and it is easy to maintenance and future modification. Each processor has specific jobs with multi-tasks software approach in order to guarantee real-time response. Master Slave communication is used for communication between processors via RS485. Discrete Proportional Integral and Different (PID) controller is used as the robot posture controller. The experiments are conducted and all the robot controller gains are tuned. The experimental results show that robot can achieve real-time operation by using the designed multi-tasks multi-processors system and the proposed controller can control robot postures with robustness.