Dynamic Modeling and Control Method of Walking Posture of Multifunctional Elderly-Assistant and Walking-Assistant Robot for Preventing Elderly Fall

A new multifunctional elderly-assistant and walking-assistant robot has been proposed in our lab to assist the elderly completing daily life and outdoor activities. The robot has two major functions, running as an intelligent wheelchair, and walking like a smart cane. When the robot assumes walking posture and the elderly is falling over, the robot adjusts to an appropriate position and supports the elderly giving balance thereby preventing fall. As a prerequisite condition that the robot supports the human balance, stability of the robot should be ensured. A dynamic model is proposed to present the stability of human-robot system. A feedforward-feedback compound control method is used to support the human balance and ensure stability of the robot. Model and simulation of the control system is conducted using Matlab/Simulink. The simulation results show the performance of fall prevention by the robot and provide a basis for the actual control system. The research process provides a reference for the stability of the elderly-assistant and walking-assistant robot system.