Method of Controlling a Tankendo Robot Using a Mecanum Wheel Trolley Robot

Tankendo which is a form of martial arts that originated in Japan is suitable for even aged persons or women and is good for promotion of health since a short and easy to maneuver shinai (bamboo sword) is used during matches as well as during practice. However, since the population of persons active in Tankendo is small, it is not easy to gain experience of actual play against other human players. In this research, the authors propose a method of control of a Tankendo robot that employs a trolley robot that uses a mecanum wheel as the movement mechanism. Although this robot cannot start suddenly or stop suddenly like humans, since it has seven pivots, it is possible to finely control the direction or posture of the vehicle as well as its speed. The control commands are of the three types of “speed”, “direction of travel”, and “rotation ratio (curvature of the curve)”, and, in addition, trapezoidal speed control is being carried out in order to prevent loss of synchronization. In other words, there is a time delay until the target speed of the control command is reached. Using a trolley robot with these characteristics, the inputs are the "robot state" (position, posture, etc.) and the "opponent state" (direction of the shinai, movement speed, distance from the opponent, etc.) at the current instant of time, and the "robot control commands" from several instants of time earlier. For the output, an optimal reference table using "speed," "direction of travel," and " rotation ratio" is machine-learned using reinforcement learning. The authors propose a robot control method that can defend against a human attack by moving to an appropriate position at an appropriate time, just before the attack becomes effective strike.