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Many kinds of power assist device have been developed. By using the exoskeleton, a high generated torque actuator can be introduced. An assistance performance of these devices becomes high. On the other hand, a realization of exoskeleton which has the same D.O.F of a human is not easy from considerations about a size and strength of device. The purpose of this study is to develop power assist device which is easy to use like normal clothes and does not restrict movement even though the assistance rate is not so high. User can be assisted by wearing this one on which the pneumatic soft actuator, which has a high power weight ratio and a light weight, is put. Final goal of this wear is to reduce a physical burden caused by heavy equipment such as a heatproof suit for a firefighter and so on. In this paper, the structure of power assist wear is discussed, and the assistance effect under the condition that a heavy load is applied to upper body is verified from iEMG.

When humans and robots implement a cooperative task, information (intention) transfer between them is an important problem as the task becomes complicated. In the paper, a haptic interface using a pneumatic parallel manipulator is developed to realize "information transfer by means of contact". The contact information given by the human, namely contact force vector and contact point on the manipulator, is detected by the interface itself and such information is transferred to the robot by being connected with some reference signal. The pneumatic parallel manipulator works as a kind of elastic body even when its position is controlled owing to the air compressibility. Focusing on this characteristic and introducing an idea of compliance center with a spherical shell, contact force vector and contact point are detected without a force sensor. The validity of the proposed method is confirmed through some experiments.

In order to make a robot perform a contact task with an environment, robot must have an enough skillfulness and compliance simultaneously.Parallel manipulator has attracted an interest because of its features such as a multiple d.o.f. for its compact mechanism which is available for complicated tasks. In the meanwhile pneumatic actuator has a high power/weight ratio and an inherent compliance function due to the air compressibility which makes it possible to perform a minute force regulation. In this paper we apply an impedance control to the prototype of parallel manipulator driven by pneumatic cylinders and its control performances are investigated.There are 2 general impedance control strategies, one is force based type and the other is position based one. In the former one the influence of manipulator's dynamics such as inertia force and damping one affect on the control variable directly, while in the latter one applied external force works as a disturbance. Therefore we construct both types of control system based on the pressure control system to kill out the influence of these disturbances which are estimated with a dimension of a pressure by using a disturbance observer. Moreover we comprise an simplified position based impedance control system. The control performances are compared among the proposed three control systems analytically and the validity of them are proved by some experiments.

Many kinds of power assist device have been developed, and are driven with various actuators such as an electric motor, a hydraulic cylinder and so on. By using the exoskeleton, a high generated torque actuator can be introduced. An assist performance of these devices becomes high. On the other hand, a realization of exoskeleton which has the same D.O.F of a human is not easy from considerations about a size and strength of device. In this study, the power assist wear for lower limb is developed. The developed wear is like trousers. A human can be assisted by just wearing trousers on which the pneumatic soft actuators are put. The pneumatic soft actuator has a high power weight ratio, and has a light weight. These features contribute to realize the simple structure which is like clothes. In this paper, the structure of power assist wear is discussed, and the application of power assist wear to assist going up and down stairs are described.

The goal of this paper is to attain a robust positioning control of a pneumatic driving system. A positioning control system positively focusing on the pressure control is investigated from the view that the pressure control is indispensable for improvement of control performances. A disturbance observer is employed to improve the pressure response and compensate the influence of friction force and parameter change. Consequently the improvements of robustness against payload and of positioning accuracy have been attained

A pneumatic driving system has been used in the production facilities of various industries. However, high performance can not be easily achieved with these pneumatic systems because of the high nonlinear properties resulting from air compressibility and friction. Therefore it has been used mainly for relatively simple tasks. Recently, pneumatic systems must have high performance since they are used for robotics and mechatronics. As a fuzzy control uses fuzzy rules described with only a qualitative relationship between the input and output of the system without any mathematical modeling, it is considered to be useful for controlled plants with high nonlinear characteristics.This study is for improving the pneumatic servo system by providing the fuzzy control with advanced functions. The hybrid controller switched from the fuzzy control to Pl control in the neighborhood of the desired position has been proposed. It is capable of improving the dynamic response when the reference position and load are changed. It has been confirmed that the fuzzy control is very effective for use with advanced pneumatic system.

A vibration isolation table must have functions of both the vibrationabsorption and the fast and accurate positioning. The concept of a two degreesof freedom control may be considered to be effective to reconcile such twofunctions. In this study, a design approach is proposed to realize this typeof control system for a pneumatic vibration isolation table, which uses thecomplementary sensitivity function as an index to adjust the parameters ofcontroller. Comparing the control performance with that obtained from an usualPI controller, it can be assured that the proposed controller is useful forthe active control of a pneumatic vibration isolation table.

In this study, we aim at developing a mechanical device to support human rehabilitation motion of their wrist joint instead of a physiotherapist. Pneumatic parallel manipulator is introduced as a mechanical equipment from a view that pneumatic actuators bring minute force control property owing to the air compressibility and parallel manipulator's feature of multiple degrees of freedom is suitable for the complex motion of human wrist joint. To cope with the shortage of physiotherapist, we propose a method to acquire P.T.'s rehabilitation motion and implement it for a patient using the equipment. The validity of the proposed system is confirmed through some experiments.

In the coming advanced age society, an innovative technology to assist the activities of daily living of elderly and disabled people and the heavy work in nursing is desired. To develop such a technology, an actuator safe and friendly for human is required. It should be small, lightweight and has to provide a proper softness. A pneumatic rubber artificial muscle is available as such actuators. We have developed some types of pneumatic rubber artificial muscles and applied them to wearable power assist devices. A wearable power assist device is equipped to the human body to assist the muscular force, which supports activities of daily living, rehabilitation, heavy working, training and so on. In this paper, some types of pneumatic rubber artificial muscles developed in our laboratory are introduced. Further, two kinds of wearable power assist devices driven with the rubber artificial muscles are described. Some evaluations can clarify the effectiveness of pneumatic rubber artificial muscle for such an innovative human assist technology.

In this study, the bilateral type pneumatic wearable master-slave device has been developed in order to feed back a force information to the trainer. Developed device is constructed with a master and a slave devices using pneumatic rubber muscles. A reaction torque of the slave device is estimated by a disturbance observer. By feeding back the estimated torque to a torque control system of the master device, a user of the master device can feel the reaction torque from the of slave. In this paper, the structure of the developed device is discussed, and then the control system is described. Finally, the validity of the proposed device is evaluated from the experiments that assume rehabilitation of an elbow.

Nowadays, the breast cancer, over ahead of stomach one, holds the highest cancer incidence rate among Japanese women. Detection of breast cancer is done by palpation diagnosis, which require doctor to have highly experienced technique. In this study, we develop a palpation simulator which forms a woman's actual breast model holding active controlled variable stiffness property. A pneumatic parallel manipulator is employed as mechanical part of our simulator. In order to display a concrete stiffness feeling to human (doctor), control strategy is proposed where the contact point is detected using an idea of graphical intersection test. A reference stiffness is realized by constructing a compliance control system. By regulating the reference stiffness value according to the contact point, a palpation motion is executed. The validity of the proposed palpation system are confirmed through some experiments and analysis.

In this study, in order to realize an assist of independent life for the elderly or people in need of care and relieve a physical burden for care worker, an active support splint driven by pneumatic soft actuator (ASSIST) has been developed. ASSIST consists of a plastic interface with the palm and arm and two rotary-type soft actuators put in both sides of appliance. McKibben type pneumatic rubber muscles are on the both sides of rotary-type soft actuators for relieving a restrained feeling when the device is not operated. In this paper, the structure of ASSIST is described, and then the effectiveness of this splint is experimentally discussed based on the experiments for movable range assist for the wrist.