Pursuit-evasion Game for Underwater Robots Considering Both Position and Orientation

This work presents a pursuit-evasion game control method for the autonomous underwater vehicle performing the interception task of a moving target. The relative state equation between the vehicle and the target is originally derived based on their motion models, both positional and orientational. And then the interception task can be perfectly formulated as a zero-sum pursuit-evasion game model with respect to the relative state between the pursuer and the evader. To avoid the chattering during the motion control process, limitations of the control input, acceleration, and velocity for the vehicle are sequentially taken into account at each time step, which avoids large jerks in the kinematical and dynamical levels. To solve the control problem, the linear quadratic differential game method with the linear quadratic assumption is adopted, and thus simplifies the game control problem with a fast analytical solution for the pursuer and the evader, respectively. Simulation cases are conducted to validate the effectiveness of the presented underwater pursuit-evasion game control method, in which the vehicle enables to intercept the moving target within several hundred meters in the finite time.