Yuzo Kaneshige

A new mobility-aid vehicle with a unique turning system

The development of assistive technologies, especially mobility devices, has an important impact on the daily activities and social participation of elderly people. The authors have developed a new mobility aid, ldquoTread-Walkrdquo, which extends mobility activities, maintains body function and maintains natural walking appearance. In the current research, we designed and developed a more natural operation system based on human walking movements. The new system concept is to use separate treadmill belts to measure the acceleration/deceleration force of each leg and use it as the input signal to change the direction of the system. This new device, ldquoTread-Walk 2rdquo, permits the user to walk naturally while a servo motor amplifies his normal walking speed. Its main components are a treadmill with two belts, two middle driving wheels, and four omni-directional casters. Sensors in the treadmill detect forward and backward reaction forces that are applied to the surfaces of the belts during walking. These forces for each leg are recognized as signal of the userpsilas intention to change direction and are used to turn the vehicle. These sensors also control the rotational speed of the driving wheel motors. Preliminary evaluations indicate that this turning system is both safe and effective for use by elderly people.

A steering system of a new mobility-aid vehicle: Tread-walk

In Japan, independent living and freedom of movement are expected, even by aged persons, and the importance of preventive medicine and walking as part of overall efforts to maintain health are continuously promoted. To those ends, we have been developing a new mobility device, known as Tread-Walk (TW), which incorporates the following concepts: ldquoimproved mobility,rdquo ldquohealth maintenance,rdquo and ldquoa natural walking appearance.rdquo The device operates by means of three controls: a free treadmill velocity control (which allows the user to walk at their desired velocity), a driving control, and a steering control. In this paper, we propose an innovative steering control method that enables users to turn the device in a safe and stable manner. The newly developed steering system was designed to provide optimum support to the physical characteristics of elderly people. Furthermore, the rotational system of the device was constructed in a way that takes into consideration the centrifugal force imposed on the center of gravity of a person who is walking or standing. A number of simulations were conducted into the properties of our new steering system and it was determined that the rotation of the TW system could be safely implemented.