Taisuke Sakaki

Estimation of intention of user arm motion for the proactive motion of upper extremity supporting robot

This research aims at the estimation of intention of user arm motion supported by the wearable type robot on upper extremity for assisting to have meal. The algorithm or the estimation was proposed and verified by the experiments to investigate the gaze pattern at selecting food images.

Estimation of Intention of User Arm Motion for the Proactive Motion of Upper Extremity Supporting Robot

This research aims at the development of the estimation function of intention of user arm motion supported by the wearable type robot on upper extremity for assisting to have meal. It is shown that the basic concept of the function and the preliminary experimental results focusing on the stability of the robot motion with the function. If the robot arm has an estimation function, it can prepare by moving proactively to the target food in order to decrease the period to reach to the target and reduce the load for operating the robot. The system with the function comprises the processes of the measurement of gaze motion, the estimating of selecting the target calculating the robot motion and robot control. However, if the robot simply follows the gaze movement, it may cause oscillatory motion which gives unnecessary load to the user. Using the discrimination technique, the robot manipulator can guide the users upper extremity to approach to the target at the timing when the decision is done by the user. The method called “Proactive type” provides the stability of the robot motion. The experimental results show the possibility to estimate in advance the position of the food plate to be selected in order to complete the estimation algorithm for the proactive assistive motion of the robot.

Impedance control of a manipulator using torque-controlled lightweight actuators

The performance of a novel actuator for advanced robots is studied in terms of its compactness and force controllability. The authors present lightweight electric actuators and compact control drivers, and their sophisticated force control performance in the execution of dexterous and compliant manipulation. State and dynamic force controllability of the proposed actuator is verified by some impedance control experiments with a three degree-of-freedom manipulator.<<ETX>>

Robotic Stretcher for SMA Patient: Preliminary Tests on Controllability and Safety

Abstract Diseases such as ALS and SMA often cause motor disabilities by progressive loss of muscle power. However, some patients must lie horizontally and thus cannot operate a wheelchair. The aim of this study was to develop a robotic stretcher for an SMA patient with severe motor disabilities to enable her to maneuver independently inside a building. In the concept of the stretcher, the user can drive the stretcher using an applicable operating device while watching a display feed from cameras mounted on the stretcher. We have developed some new devices with operating algorithm, mechanical frame and control system suitable to the users limited abilities (motion in only one finger), and verified their functions by tests with prototype machine. In addition, we show some results of a risk assessment of the prototype machine.

An effective design method for welfare robot and its application to the design of meal-assistance robot

Recently, many welfare robots have been developed to solve problems in elderly society. However, very few welfare robots have been successfully commercialized. One of the reasons for the difficulty in commercializing them is the insufficient method of designing those kinds of robots. The present research aims to develop an effective design method for welfare robots. The author proposes a method focusing on the early stage of the mechanical design as the conceptual and basic design process: 1) prior research to investigate the conditions for evaluating the design, 2) arranging the goal for the evaluation items, 3) preliminary tests to investigate the standards of evaluation, 4) mock-up to determine the standards, and 5) specifications for detailed design. The proposed method concentrating on the concept design is applied to the design of a meal-assistance robot mechanism. The design derived by the proposed method is quite similar to the concept of the most recent version of the robot developed by the conventional design method as determined by interviewing medical staff.

Rehabilitation robots assisting in walking training for SCI patient

We have been developing a series of robots to apply for each step of spinal cord injury (SCI) recovery. We describe the preliminary walking pattern assisting robot and the practical walking assisting robot, which will be applied to the incomplete type of SCI to Quadriplegia. The preliminary experimental results are performed by normal subjects to verify the basic functions of the robot assisting and to prepare the test by SCI patients.

Rehabilitation Robot in Primary Walking Pattern Training for SCI Patient at Home

Recently, attention has been focused on incomplete-type spinal cord injury to the central spine caused by pressure on parts of the white matter conducting pathway such as the pyramidal tract. In this paper, we focus on a training robot designed to assist with primary walking pattern training. The target patient of this training robot is one who is relearning the basic functions of the usual walking pattern, especially for patients with the incomplete type SCI to the central spine, who are capable of standing by themselves but are not capable of performing walking motions. From the perspective of human engineering, we monitored the operator’s actions to the robot and investigated the movement of joints of the lower extremities, the circumference of the lower extremities and the exercise intensity with the machine. The concept of the device is to provide mild training without any sudden changes in heart rate or blood pressure, which will be particularly useful for the elderly and disabled.

Robotic stretcher for spinal muscular atrophy patient: Preliminary tests of user controllability

Diseases such as amyotrophic lateral sclerosis and spinal muscular atrophy (SMA) often cause motor disabilities through the progressive loss of muscle power. However, some patients must lie horizontally and thus cannot operate a wheelchair. The aim of this study was to develop a robotic stretcher for an SMA patient with severe motor disabilities to enable her to maneuver independently inside a building. The concept underlying the stretcher is that the user should be able to drive the stretcher using an applicable operating device while watching a display feed from cameras mounted on the stretcher. We have developed new devices with an operating algorithm, mechanical frame and control system suitable to the users limited abilities (motion in only one finger), and verified their functions through tests of a prototype machine operated by the target user.

Development of rehabilitation device for standing position weight bearing exercise using Wii balance board

Partial weight-bearing exercise is widely used in rehabilitation for patients with lower limb injuries. It is intended to help patients learn to what degree they can bear weight on the affected limb. General weight scales are widely used for this exercise to measure weight-bearing. These are easy to introduce, but involve some problems. One is that patients cannot easily read the scale to calculate weight-bearing rate. The purpose of this study is to develop a rehabilitation device to address this problem. The device combines the Nintendo Wii Balance BoardTM and a PC. It allows patients to observe the display unit while the device automatically calculates weight-bearing rate. In addition, patients can enjoy exercise with the Game Mode.

Rehabilitation robot in primary walking pattern training for SCI patient: Training robot for home-use based on the experiments of the hospital-use type

Recently, attention has been focused on incomplete-type spinal cord injury (SCI) to the central spine caused by pressure on parts of the white matter conducting pathway such as the pyramidal tract. In this paper, we focus on a training robot designed to assist with primary walking pattern training. The target patient of this training robot is one who is relearning the basic functions of the usual walking pattern, especially for patients with the incomplete type SCI to the central spine, who are capable of standing by themselves but are not capable of performing walking motions. We investigated the movement of joints of the lower extremities, the circumference of the lower extremities and the exercise intensity with the machine. From the experimental results the training robot for home-use based on the experiments on the hospital-use type is proposed. The operating panel, accessibility from wheel chair to the robot and the mechanism were modified for the home-use.