Takehito Kikuchi

Development of isokinetic exercise machine using ER brake

ER fluid has rheological characteristics which can be controlled by the electric field. Using particle-type ER fluid, we developed a brake device. In this study, this ER brake was used in an isokinetic exercise system for rehabilitation training under restriction of constant rotational speed of a joint during exercise. Such a passive system using a brake is basically safe for human use.

Quasi-3-DOF Rehabilitation System for Upper Limbs: Its Force-Feedback Mechanism and Software for Rehabilitation

Rehabilitation robots are effective to evaluate quantitatively rehabilitative therapies. Some kinds of haptic devices have been developed by many researchers and evaluated its efficiency with clinical tests for example upper limb training for patients with spasticity after stroke. Almost all the devices for upper limb rehabilitation have only 2-DOF for its active motion (except for wrists). But the upper limb of human works in 3-D space even except for the wrist; therefore designing a rehabilitation system for 3-D training is important. We developed new haptic devices which have 2-DOF force-feedback function on a worktable but the inclination of the worktable can be adjusted. We named this system Quasi-3-DOF Rehabilitation System for Upper Limbs or PLEMO. In this paper, we describe the mechanism of PLEMO and its software for the upper limb rehabilitation.

Development of Shear Type Compact MR Brake for the Intelligent Ankle-Foot Orthosis and Its Control; Research and Development in NEDO for Practical Application of Human Support Robot

A brake in which the magnetorheologic fluid (MRF) is used has a simple structure and good responsibility. Therefore, MR brake is expected to perform a good adaptability for human-coexistence system. Being applied in an ankle-foot orthosis, however, conventional MR brake is too large to fit. Then, in this study we developed a shear-type MR brake with multi layer disks and minute gaps (50 micrometers) to realize compactness and high performance. This paper describes the development of a shear type compact MR brake and a new controllable ankle-foot orthosis with this brake. Furthermore, we design algorithm to control an ankle. We assist gait of a patient by changing a brake force.

Leg-Robot for Demonstration of Spastic Movements of Brain-Injured Patients with Compact Magnetorheological Fluid Clutch

In this study, we propose a leg-shaped robot (Leg-Robot) with a compact magnetorheological fluid clutch to demonstrate several kinds of haptic control of abnormal movements of brain-injured patients. This system can be used in the practical training for trainees of physical therapies (physiotherapists). In this paper, we especially focus on ankle clonus, which is one of the abnormal movements usually arising after stroke. We suggest a control method to demonstrate haptics of the ankle clonus. We also confirmed its effectiveness for learning of the test skill.

Compact MR fluid clutch device for human-friendly actuator

In this paper, we describe a design method and experimental results of a newly developed MR Fluid clutch which has a multi-layered disks and micro-size (50 micro meters) gaps of MR Fluid. The micro-size gap works for the reduction of magnetic resistance, amount of power supply and size of the total system. Static torques of the device was predictable with conventional magnetostatic analyses. Additionally, dynamic test shows that its response time is about 20 milliseconds.

A 6-DOF Rehabilitation Support System for Upper Limbs including Wrists "Robotherapist" with Physical Therapy

Rehabilitation for upper limbs is important for aged people, stroked patients and so on. In recent years, the needs for rehabilitation support systems are increasing, which use robot technology and virtual reality technology. Applying these technologies make efficient rehabilitation possible. But there is no rehabilitation support system that has 6-DOF for upper limbs including wrists besides application software of physical therapy. We developed a 6-DOF-rehabilitation support system for upper limbs including wrists, named Robotherapist. Furthermore we develop new application software for clinical training and evaluation on the basis of physical therapy. Therefore Robotherapist make more effective rehabilitation possible. This paper presents the mechanism of Robotherapist and its software on physical therapy.

Intelligently controllable Ankle Foot Orthosis (I-AFO) and its application for a patient of Guillain-Barre syndrome

Ankle-Foot Orthoses (AFOs) are orthotic devices supporting movements of ankles for disabled people for example hemiplegia, peroneal nerve palsy, etc. In our research, we have developed the intelligently controllable AFO (I-AFO) which can control its ankle torque by using compact Magneto-rheological fluid (MRF) brakes. In this paper, we describe the gait-control tests with I-AFO for a patient of the Guillain-Barre syndrome. The subject has difficulty in his voluntary movement of the peripheral part of the inferior limb, and there are physical limitations on his ankle. By applying the I-AFO, his gait control was improved by the prevention of drop-foot in the swing-phase and the forward promotion in the stance-phase.

Development of a 6-DOF Force Display System with High Safety and its Application to Rehabilitation

Movements of the upper limbs are indispensable for daily activities. Rehabilitation for upper limbs is important for aged people or patients of paralysis caused by stroke. Because of aging of society, the number of stroke patients will increase more in the near future. In recent years, the needs for rehabilitation support systems are increasing, which use robot technology and virtual reality technology. Applying these technologies make efficient rehabilitation possible. This paper presents the development of a 6-DOF rehabilitation system for upper limbs including wrists. This system ensures efficient rehabilitation training which focus on the harmonic movement of the whole upper limb

Initial clinical tests for assessment models of synergy movements of stroke patients using PLEMO system with sensor grip device

In recent years, many researchers have studied on the rehabilitation robotics to assist medical staff or patients. Some kinds of haptic devices have been developed and evaluated its efficiency with clinical tests, for example, upper limb training for patients with spasticity after stroke. Almost all the devices for upper limb rehabilitation have only 2-DOF for its active motion except for wrists. But the upper limb of human works in 3-D space even except for the wrist; therefore designing a rehabilitation system for 3-D training is important. To meet this demand, we have developed a rehabilitation system for upper limbs, “PLEMO”. PLEMO is a kind of haptic device. However, in the previous system, we could not detect symptoms of abnormal movement of patients, for example synergy patterns of stroke patients, because of a lack of sensors. In this paper, we developed new sensing device for detecting such abnormal symptoms. The purpose of this study is to build an appropriate evaluation system for stroke patients with such information of abnormal symptoms. As a first step, we conducted reaching/pulling tests with this device. In this clinical evaluation, the subject is six stroke patients with different Brunnstrom stages (3, 4, 5) and twenty seven healthy subjects. By comparison with a patient movement (stage 3, 4, 5) and a normal movement, we recognized some differences of gripping forces, grip rotation angle and ground reaction forces among their movements.

Development of Quasi-3DOF upper limb rehabilitation system using ER brake: PLEMO-P1

In recent years, many researchers have studied the potential of using robotics technology to assist and quantify the motor functions for neuron-rehabilitation. Some kinds of haptic devices have been developed and evaluated its efficiency with clinical tests, for example, upper limb training for patients with spasticity after stroke. However, almost all the devices are active-type (motor-driven) haptic devices and they basically require high-cost safety system compared to passive-type (brake-based) devices. In this study, we developed a new practical haptic device PLEMO-P1; this system adopted ER brakes as its force generators. In this paper, the mechanism of PLEMO-P1 and its software for a reaching rehabilitation are described.