Hiroaki Kawamoto

The Hybrid Assistive Limb (HAL®) is an exoskeleton wearable robot suit that assists in voluntary control of knee and hip joint motion. There have been several studies on HAL intervention effects in stroke, spinal cord injury, and cerebral palsy. However, no study has investigated HAL intervention for patients with cerebral palsy after surgery. We report a case of using HAL in a postoperative patient with cerebral palsy. A 15-year-old boy was diagnosed with spastic diplegia cerebral palsy Gross Motor Function Classification System level IV, with knee flection contracture, equinus foot, and paralysis of the right upper extremity with adduction contracture. He underwent tendon lengthening of the bilateral hamstrings and Achilles tendons. Although the flexion contractures of the bilateral knees and equinus foot improved, muscle strength decreased after the soft tissue surgery. HAL intervention was performed twice during postoperative months 10 and 11. Walking speed, stride, and cadence were increased after HAL intervention. Post HAL intervention, extension angles of the knee in stance phase and hip in the pre-swing phase were improved. In the gait cycle, the proportion of terminal stance in the stance and swing phase was increased. Hybrid Assistive Limb intervention for postoperative patients with cerebral palsy whose muscle strength decreases can enhance improvement in walking ability. Further studies are needed to examine the safety and potential application of HAL in this setting.

We propose a design for an ultra-multijointed assistive robot finger. Gripping necessitates the flexion and extension of a finger and is a basic function in daily life. Therefore, to enable people with hand paralysis to grip, it is necessary to assist their finger movement. To do so, we propose a novel ultra-multijointed assistive robot finger mechanism. This mechanism consists of many joints, wires, a finger frame, and a movement point. These joints enable the structure to adapt to the length and location of the wearer's finger and assist its bidirectional movement. The mechanism is moved by a linear power unit driven by a wire. Two assistive robot fingers are glued onto a glove to enable the user to stably grip everyday objects. We carry out four experiments to confirm the finger's range of motion, basic flexion and extension motions, flexion force of the fingertip, and grip performance for everyday objects. Experiments with five able-bodied participants show that the assistive robot finger does not limit the hand's range of motion. Furthermore, our assistive robot finger can assist finger movement. The force of the fingertip is more than 9.8 N, allowing everyday objects to be gripped successfully. Hence, the assistive robot finger developed in this study may have the potential to help those with hand paralysis grip everyday objects.

下肢機能障害者にとって立ち座り動作を日常的に行うことは，運動・生理機能の維持・改善だけでなく，自立した生活を送るための第一歩として非常に重要な役割を有する．しかし，日常的に自立した生活の中で立ち座り動作の学習を促進し運動機能改善を可能とする支援技術の研究開発は未開拓領域であった．我々は，立ち座り動作の自立的な再獲得および脳神経科学に基づいた下肢機能障害者の立ち座り動作の改善を実現するために，装着の手間が少ない方法で人-機械間の情報的・物理的なインタラクションが可能な立ち座り型サイバニックシステムを新たに提案・研究開発してきた．本解説では，立ち座り型サイバニックシステムの特色と本システムを用いた立ち座り動作の学習による脳神経系と末梢系の神経情報伝達ループの再構成へ向けた取り組みに関して述べる．

The purpose of this research was to propose a control method for Robot Suit HAL to provide walking support for hemiplegic patients, and to confirm its effectiveness. Support for the affected side of a patient's body was provided using motion data from the unaffected side. The HAL was used to sense angle and angular velocity data for the hip and knee joints on the unaffected side, and to generate motion in these joints on the affected side using feedback control based on the motion of the unaffected joints. Clinical experiments were conducted with a stroke patient with hemiplegia, to validate the proposed control method and evaluate the change of the patient's gait with and without wearing HAL. The results revealed that the affected side could be made to perform effectively by generating motion based on that of the unaffected side. As a result, symmetrical gait appeared significantly.

The purpose of this research was to develop a control method for Robot Suit HAL, in order to provide walking support for hemiplegic patients. Support for the affected side of a patient's body was provided using motion data from the unaffected side. The HAL was used to sense angle and angular velocity data for the hip and knee joints on the unaffected side, and to generate motion in these joints on the affected side using feedback control based on the motion of the unaffected joints. Initial experiments were conducted with an able-bodied subject, to validate the proposed control method. The results revealed that the affected side could be made to perform effectively by generating motion based on that of the unaffected side.

Our goal is to enhance the quality of life of patients with hemiplegia by means of an active motion support system that assists the impaired motion such as to make it as close as possible to the motion of an able bodied person. We have developed the Robot Suit HAL (Hybrid Assistive Limb) to actively support and enhance the human motor functions. The purpose of the research presented in this paper is to propose the required control method to support voluntarily motion using a trigger based on patient's bioelectrical signal. Clinical trials were conducted in order to investigate the effectiveness of the proposed control method. The first stage of the trials, described in this paper, involved the participation of one hemiplegic patient who is not able to bend his right knee. As a result, the motion support provided by the HAL moved the paralyzed knee joint according to his intention and improved the range of the subject's knee flexion. The first evaluation of the control method with one subject showed promising results for future trials to explore the effectiveness for a wide range of types of hemiplegia.

Our goal is to try to enhance the QoL of persons with hemiplegia by the mean of an active motion support system based on the HAL's technology. The HAL (Hybrid Assistive Limb) in its standard version is an exoskeleton-based robot suit to support and enhance the human motor functions. The purpose of the research presented in this paper is the development of a new version of the HAL to be used as an assistive device providing walking motion support to persons with hemiplegia. It includes the realization of the single leg version of the HAL and the redesign of the original HAL's Autonomous Controller to execute human-like walking motions in an autonomous way. Clinical trials were conducted in order to assess the effectiveness of the developed system. The first stage of the trials described in this paper involved the participation of one hemiplegic patient who has difficulties to flex his right knee. As a result, the knee flexion support for walking provided by the HAL appeared to improve the subject's walking (longer stride and faster steps). The first evaluation of the system with one subject showed promising results for the future developments.