Kengo Ohnishi

Home-Use Upper Limb Rehabilitation Device for Cervical Spinal Cord Injured Patients

This paper presents mechatronics device system to assess and assist the rehabilitation of the palsy arm. The device is developed for assisting the physical and occupational treatment of the patient with cervical spinal cord injury. The system consists of a PC and a joystick-type controller. The controller contains a triaxial load cell to measure the force exerted. With this system, we propose isometric training with biofeedback of visual effects as in video games. The subject is to adjust the force while tracking the target along the trajectory displayed on the screen. For evaluating the performance, accuracy is computed from the recorded training results. Pilot test is carried out on cervical spinal cord injured patients and compared with the senior able-bodied. Results of the pilot test showed that the system is capable of assessing the difference of the individuals.

Field test of a force control rehabilitation system for quantitative evaluation of the disorder in the upper extremities

This paper reports on a field test of our simple force-sensor-based rehabilitation device that can be handled at homes or neighboring medical institutions. We propose a tri-axial load cell controller system for quantitatively evaluating the visually guided motor control characteristic of a weak palsy arm. The result is recorded in the database while evaluation is presented for each trial. The system is tested at an orthopedic clinic with outpatients: cervical spinal cord injured patient and 2 other cases. Their mid-term testing results are discussed.

The Development of Gait Training System for Computer-Aided Rehabilitation

This paper reports on the development of a gait training system and its experimental results. The outstanding feature of the system is the constant dynamic adjustment of the tension lifting the trainee based on the information from floor reaction force. The load on the trainees foot on the floor is regularly maintained at a low-burden level; therefore, the load on the foot is similar to the effect of walking in a pool. The system was tested on a handicapped person, and improvements in balancing ability were shown.

A gait training system for human adaptive walking posture

This paper deal with the modification of a gait training system. This system is designed to produce artificially similar the effects to gait training in a swimming pool. The weight of the patient is supported by a slinging system, while the patient walks on force plates placed on a round track. The slinging force is controlled by the data collected from the force plates. The purpose of the system is to control the slinging force to maintain the most effective load on the patients lower extremity during training, and to adapt the slinging force to the patients recovery. To achieve this purpose, the load meter on the force plate is designed to enhance the measurement performance. Tests revealed that dynamic response improved with the new design. Furthermore, the human interface also improved by mounting a display that projects the patients foot by means of a movie camera. The patients gait posture can be significantly improved by adapting this method.

Development of a robotic digit joint mechanism for knot tying task

In this paper, we propose a novel transmission mechanism for developing a robotic hand for performing knot tying task. Our goal is to develop a robotic hand system that supports the people with disability in dexterous hand movements. The target is to handle clothing and other soft material which require both precision and strong grasp during its sequence. First, the design concept is discussed by analyzing the digit movements and their functions in a knot tying sequence. An issue of developing transmission mechanism is discussed from the result. A mechanism applying a swash plate cam is presented for joint movement control to minimize weight and complexity, while being capable of holding high torque. A prototype digit is assembled and tested to confirm its characteristic and discussion of future modification is presented.

An examination about walking posture on Gait Training System for computer-aided rehabilitation

Our Gait Training System is a training device that aims to obtain the effect of the walk training in the warm water swimming pool. A trainee is supported by the slinging system while walking on the force plate. Slinging power is controlled on the basis of information instrumented from the force plates. The training effects are evaluated on the basis of the data that obtained from the force plate etc. This system is tested by handicapped person to inspect the function and efficacy. A major problem of deficient body alignment of the walking posture is found from the test. We propose mounting a monitor and the result of improvement is shown. The effect on the walking posture using the Gait Training System is experimented on normal persons. The difference of the posture in normal gait and device-supported gait is shown.