Walking Support and Power Assistance of a Wheelchair Typed Omnidirectional Mobile Robot with Admittance Control

Abstract

Walking ability is essential for the elderly/the disabled’s self-supported daily life. Currently the development of various robotic aids or devices for helping the elderly’s walking has attracted many researcher’s attentions. Guidecane ((Ulrich & Borenstein, 2001)), PAM-AID ((Lacey & Dawson-Howe, 1998)), Care-O-bot ((Graf et al., 2004)), PAMM ((S. Dubowsky, 2000)), and etc, are developed for intelligent walking support and other tasks for the elderly or the disabled. Mainly for the elderly’s walking support, a robotic power-assisted walking support system is developed (Nemoto & M. Fujie, 1998). The system is to support the elderly needing help in standing up from the bed, walking around, sitting down for rehabilitation. Meanwhile, a number of intelligent wheelchair-type aids are being designed for people who cannot walk and have extremely poor dexterity ((Yanco, 1998)-(Dicianno et al., 2007)). These devices are well suited for people who have little or no mobility, but they are not appropriate for the elderly with significant cognitive problems. Consequently, the facilities are generally reluctant to permit the elderly residents to use powered wheelchairs. Hence, the better solution is that the facility staff (the caregiver) pushes the wheelchair to move. Some technologies for the caregiver’s power assistance are proposed ((Kakimoto et al., 1997)-(Miyata et al., 2008)). Further, since the omnidirectional mobility is necessary to truly yield the user’s (here refer to the elderly/disabled, or the caregiver) intentions of walking speed and direction, omnidirectional mobility is investigated in order to obtain a smooth motion and high payload capability, not with the special tires but with the conventional rubber or pneumatic tires. An omnidirectional and holonomic vehicle with two offset steered driving wheels and two Walking Support and Power Assistance of a Wheelchair Typed Omnidirectional Mobile Robot with Admittance Control 5