General Kinematics and Simulation for Mobile Robot Adapted Three Unconstraint Rollers

In recent years, efficient mobility is required for omni-directional mobile robots in the logistics industry. There are various types of rollers mounted on mobile robots. Among them, omni-directional rollers (omni roller) are considered to have excellent omni-directional mobility and easy control. Assuming a circular mechanism, kinematics has been derived assuming an arbitrary arrangement along this circumference, and several studies have evaluated roller arrangements in terms of the speed efficiency of the driving rollers. To evaluate the roller arrangement, kinematics is necessary, in which not only the contact position of the rollers but also the direction is a parameter. In this study, kinematics is derived for a mobile robot equipped with three omni-rollers, with the contact position and direction of the rollers as parameters, and the behaviors of the roller velocity is investigated for the robot's movement in all directions.