Kazuaki Sakai

Improvements of manipulation torque transfer mechanism and assist unit for one hand drive wheelchair with a triple ring

We develop a one hand drive wheelchair with original manipulation mechanism and power assist mechanism. In this investigation, first, we improve the transfer mechanism of this wheelchair. As a result, using an improved mechanism, the running resistance of the wheelchair decreased with about 1/2 to the previous one. The effects of this improvement are verified by long distance drive experiment using some one hand drive type wheelchairs. Secondly, we develop the assist unit, which has a new on/off mechanism constructed by link and sliding mechanism, in order to realize the sure assist torque transformation. During assist, improved unit surely keeps the distance of two rollers, which transfer assist torque to tires. Therefore, assist torques, provided by DC motor, are surely transfer to tires.

Torque measurement experiments of a torque detection mechanism implemented on hand-rims of a one hand drive wheelchair

We have been developed an original one hand drive wheelchair. This wheelchair has the original manipulation mechanism with a triple ring and power assist units, which realize some assist functions, the power assist function, the reverse prevention function on upward slops and so on. Furthermore, we have proposed a simple and useful manipulation torque detection mechanism. In this paper, we demonstrate results of torque measurement experiments, which shows that even if the grasping position of the hand on hand rims changes, the accurate detection of manipulation torque can be realized. The result, presented in this paper, shows the validity of the proposing torque detection mechanism.

Detection mechanism of manipulation torque for one hand drive wheelchair with a triple ring

A one hand drive wheelchair with power assist mechanism is developed. In this investigation, we propose a simple and useful manipulation torque detection method which yields wide detection areas with uniform distribution of stress. This method can be applied to a one hand drive wheelchair with complicated structure of manipulation mechanism with three rings. Moreover, even if the grasping position of the hand on hand rims changes, the accurate detection of manipulation torque can be realized. Therefore, it improves the controllability and the operability of the wheelchair. Numerical results given by FEM show the effectiveness of proposed method.

A strategy for step climb using wheelie on a one hand drive wheelchair with a triple ring

We have been produced a one hand drive wheelchair, which has the original manipulation mechanism with a triple ring and oower assist units. In this wheelchair, some assisi functions realize comfortable drive. In this paper, we newly develop an assist function of the one hand drive wheelchair, which realizes a step climb by using wheelie. We propose a strategy for the step climb using the manipulation mechanism and the assist unit. The usefulness of the proposed assist function is verified by experiments using a prototype.