Platform development of an omnidirectional mobile robot for the elderly's walking support and the caregiver's power assistance

In this paper, we proposed a new concept for omnidirectional mobile robot that not only can fulfill the walking support or walking rehabilitation for the elderly or the disabled, but also can realize power assistance for the caregiver when he/she holds the robot handle to move the robot while the elderly or the disabled is sitting in the seat. We postulated four necessary functions the robot should have and developed a test-bed robot platform for verifying the necessary functions and the technologies being developed. The most basic function of the robot, omnidirectional mobility realized by two active dual-wheel modules, is focused to discuss in detail. We first discussed the kinematics of an active dual-wheel module and pointed out that two modules are necessary to realize omnidirectional mobility. After we analyzed the omnidirectional mobility of two modules and derived the inverse kinematics of the robot, initiative and verification experiments are implemented and the robot's omnidirectional mobility is experimentally verified.