Motion control of intelligent cane robot under normal and abnormal walking condition

In this study, we present an omni-directional cane robot for aiding the elderly and handicapped people walking. The motion control problem is investigated for both normal and abnormal walking conditions. In the case of the user´s normal walking aided by the cane robot, a concept called “Intentional Direction (ITD)” is proposed. Guided by the online estimated ITD, we apply the admittance control method in the motion control of cane robot. The gravity compensation is also considered because the user is possible to walk on a slope. For the abnormal walking, we mainly studied the case of user´s falling down. The Center of Gravity (COG) of user can be estimated from the angle of an inverted pendulum which represents human model. Fall prevention algorithm based on the relationship between user´s COG and the cane is proposed. This algorithm is also applied in the motion control of cane robot. The proposed method are verified through experiments.