In this project, we developed a robotic walking support system with an omni-directional mobile base. Its objective is to assist elderly or handicapped people in their daily activities and improve their quality of life.  We have proposed a motion control algorithm to aid the users who cannot properly control their walking support system. It changes the maneuverability of the system based on the concept of a variable center of rotation to aid the user. Experimental results show the validity of the proposed motion control algorithm.