A human can perceive the hardness of an object by tapping its surface. Hardness perception based on tapping is applied to rendering a virtual object in virtual reality systems, however little is known about the physical factor which affects the perceived hardness. We discussed the effects of the representative parameters on perceived hardness by psychophysical and mechanical experiments on real objects. We compared the ranked subjective hardness values and physical properties of objects, including their stiffness, viscosity, density, and Shore hardness, and the frequencies and time constants of the natural vibrations caused by tapping. The stiffness, frequency, and viscosity exhibited a relatively strong positive correlation with the perceived hardness. The results show that the viscosity influences the hardness perceived by tapping, as well as the stiffness, whereas the stiffness and elasticity are considered to be major factors in the hardness perceived by pinching or pushing.

Multi-sensory illusion in rubber hand illusion is a well known haptic illusion in the literature. In this study, we introduce Multi-sensory illusion into a form of master slave system to realize a further operability. As a preliminary test, we developed a 1 DOF bilateral rubber hand master slave system and investigated the effect of force feedback on Multi-sensory illusion.

In this research, we aim to modify a feeling of walking by applying vibration on sole. To apply the vibration, we developed a vibration application device with a vibrator attached on the sole of a clog. The intensity of the vibration was determined based on the difference in the acceleration obtained between while walking on the target and current ground conditions. Experimental results showed that some of feelings of walking can be modified by the proposed device.

In this paper, we propose a novel method to form a robot skin sensor by a piezoelectric material spraying technique. By spraying piezoelectric material and a pattern of electrodes, the robot skin is fabricated on a robot with 3D free form. We describe our method briefly, then report two fundamental experiments. According to the results, we confirm that a tactile sensor fabricated by our proposed method is applied for a robot skin sensor.

There are a lot of patients with movement impairment who are paralyzed by brain stroke. Sufficient rehabilitative training is necessary for these patients. Furusho and collaborators developed active type 3D Upper Limbs rehabilitation system EMUL at the 5-year NEDO Project and and 6-DOF Upper Limbs rehabilitation system “Serafy “ at the 2-year NEDO Project. Then, Passive type rehabilitation systems using brakes PLEMO series have been developed by Furusho Lab at the Osaka University and Fukui University of Technology. In this paper, the first prototype system of PLEMO-Z which is practical use version of rehabilitation system PLEMO series is presented.

There are a lot of patients with movement impairment who are paralyzed by brain stroke. Sufficient rehabilitative training is necessary for these patients. Furusho and collaborators developed active type 3D rehabilitation systems EMUL and Serafy at the NEDO Projects. Then, Passive type rehabilitation systems using brakes PLEMO series have been developed by Furusho Lab at the Osaka University and Fukui University of Technology. In this paper, improvement of upper limbs rehabilitation system PLEMO-Y(Kaken) is presented.

In this paper, brain-machine-interface for electric wheelchair using a bio-signal headset Emotiv EPOC is proposed. An electroencephalogram (EEG) of concentrated state and of relaxed state is distinguished using support vector machine (SVM), and crunching is detected based on the threshold criteria for electromyogram (EMG). Then, the electric wheelchair is controlled so as to move forward when user's concentration on consciousness is identified and stop when user's crunching movement is detected. In addition, accuracy of the identification rate for EEG was investigated. As a result, the concentration on consciousness was distinguished with 77.5% accuracy within 3.0 seconds in wheelchair operation environment. Realization of left-turn and right-turn is left as future work.

The five-wheeled wheelchair is composed by a manual wheelchair with an add-on mechanism on the back of a wheelchair. The add-on mechanism has the link configuration with the active-caster drive unit and the linear actuator. The active-caster is used for propelling the wheelchair and the linear actuator is used for changing the posture of the wheelchair. In our previous work, we confirmed that the proposed wheelchair could climb over a 100 mm step stably. In this paper, we propose the step descending strategy of the wheelchair and derive the design condition to satisfy the step climbing/descending strategies. Also, we propose the motion control system for the step climbing and descending motion.

Electric wheelchairs have been widely used by the elderly and care recipients. Since the wheelchairs require hand-operation, drivers cannot deal other tasks requiring their hands. It is preferable driver's hands is free for safety. Additionally it can get over a low level difference smoothly. In this study, an inverted pendulum type wheelchair is developed that enables turning based on sensing air pressure of the cushion, and back and forth movements by the motion of the driver without the hand-operation. Back and forth movements and rotational control systems for the wheelchair are designed using a disturbance observer.

To enable coordinated motion of the robotic wheelchair with a caretaker, position detection of the caretaker is indispensable. In this study, we developed a caretaker’s position detection system using electro-magnetic fluctuation (EMF) sensor and EM emitter. We installed three sensors behind the wheelchair and an emitter on the caretaker's waist. Experiment showed the ability to detect distance, direction, and touch status of the caretaker by using received signal strength indicator (RSSI).

In this paper, an android application for the sake of life rhythm improvement and dementia prevention is proposed for elderly people. This application has mainly 3 modes: alarm mode, friendly mode and game mode. In the alarm mode, by setting the time, users are informed the time for wake-up, breakfast, lunch, taking medicine, dinner and going bed through voice and text. The purpose of the friendly mode is to give users animal therapy effect like communication robots. In the friendly mode, users can touch a 3D cat model in the application, and can feed and pet the cat. This encourages users to keep using this application through mutual communication between users and the cat. In the game mode, two types of brain training games are prepared for users. One is a calculation game in which the randomly selected 20 questions about additions, subtractions or multiplications are given to users, and percentage of correct answers is shown at the last. The other is a rock-paper-scissors game to train use's judgement ability. Eventually, it is considered that elderly people with slight dementia can improve their life rhythm by using this application and wandering of those people at night can be decreased. In the future, in order to evaluate the developed application, verification through clinical experiment is required.

Now, low birthrate and longevity are progressing in Japan, the balance of the elderly and the young are largely collapsed. In addition, the care staff tends aging, when doing the nursing which is hard labor, it's worried to be interfered. Therefore intended to make up for the physical handicap of the elderly person by exercise support, the power assist suit is studied and developed. In this research, using water as a working fluid, propose a power assist suit that employs a combination of syringe and bellows. To manufacture this actual machine in this report, the required data of the actuator was measured.

In this study, a tactile feeling feedback device for myoelectric prosthetic hand users has been developed, in which the tactile feeling is conveyed to users by vibration. A miniature track ball (MTB) is attached to the fingertip of the myoelectric prosthetic hand and is used as a roughness sensor. Surface roughness is divided into 3 levels, which are rough, middle and smooth. Surface roughness of the object is measured by moving the MTB to a certain direction, and is identified as one of the roughness levels. In accordance with the identified roughness level, magnitude of vibration presenting to the user and presenting time are determined. In addition, direction to present vibration is calculated based on rotated direction of the MTB. The tactile feeling feedback device is mounted on an upper arm of the user, which has 9 vibration motors in cross alignment. Then, the tactile feeling is conveyed through vibration corresponding to the identified roughness by driving the vibration motors to the derived direction in turn. Finally, roughness identification and vibration distinction experiment was carried out to verify an effectiveness of the proposed tactile feeling feedback device.

Home Oxygen Therapy (HOT) patients must take the conveyance cart to carry oxygen equipment when they go out. However the equipment is heavy enough to discourage the patients from going out. Therefore we attempt to develop a mobile robotic conveyance, which is similar to the wheeled walker, to support HOT patient's going out.In this paper, we describe the mechanism of our developed prototype robotic cart which is lightweight and has a capability of getting over the steps or obstacles on the road.

Electric prosthetic hands for trans-radial amputees require low cost and high functionality. We propose a 2-DOF electric prosthetic hand with end effectors which can be changed depending on the situation. As end effectors we have produced a three-fingered hand for grasping various kind of objects and an end effector with moving chopsticks for eating. Moreover, a rotation mechanism is placed in the wrist part of the developed electric prosthetic hand to reduce compensatory motion. We perform an experiment to verify the usefulness of our solution. In addition, it can be produced easily and cheaply using a 3D printer.

An aging population in Japan has resulted in increase in the number of aged wheelchair users. They usually have difficulties in daily life such as taking bath and going to a lavatory, and they need assistance with transferring task by others such as caregivers. The assistance of transferring makes heavy physical burden on caregivers because they need to lift the elderly, although transferring is important behavior to be deeply related to going to a lavatory and a bath. In this paper, we propose an assistive robotic system for transferring a patient between a wheelchair and a bed that is small size, user-friendly and simple mechanism.

Data collection of EMG data with muscle fatigue is a time-consuming task because the rate of muscle fatigue accumulation varies according to individual. We propose an efficient data collection method of EMG data with muscle fatigue by adjusting load and duration given to each subject based on an objective criterion, that is, mean power frequency of EMG. We have demonstrated that the proposed method could reduce redundant data collection for a subject who is a recreational athlete with high endurance through data collection of EMG data of the hand opening and closing with muscle fatigue.

Goniometer and flexible Goniometer are used for measuring range of motion (ROM). However the method of measuring ROM of wrist with Goniometer has many problems. For examples, it can not measure wrist's motion mixed with motion of ulnar and radial flexion and palmar and dorsal flexion, it is difficult for dividing wrist's motion from motion of pronation and supination by arm and it has limitation on measurable ROM due to low elasticity of Goniometer. Therefore, we are developing the new type measurement system for ROM of wrist. In this paper we explain the measurement system for ROM of wrist. And we measure the ROM of healthy parson by using the measurement system. From measured data, we confirmed that measurement system can measure the ROM.

It is known that a passive dynamic walk for a biped robot is stabilized by limiting its angle of the ankle of the stance leg. Since the passive dynamic walk has a similarity with a relaxed human walking, it is anticipated that the ankle angle limitation also contributes to stabilize a human walk. In previous researches, we realized this ankle angle limitation mechanism into human shoes, and showed the stability effect of this shoes by recording integral EMG signals at the muscles that are known to contribute to posture control of a leg. In this paper, we show that the proposing shoes do not produce unnatural ankle torque and thus lighten load of legs in natural way during a walk. The analysis is done by the gait analysis using 3D motion sensors with force plates.

In this paper, we propose the cane that has shape-fitting mechanism to support a user on uneven terrain. The mechanism allows to fit to the ground passively. The grounded part consists of three shape-fitting fingers and the center rod. We explain the detail of the grounded part and three experiments about the performance evaluation.

In the aging society, the demand of the movement assisting devices for the elderly gradually increases. As one of these devices, an electric wheelchair is used. An electric wheelchair has two passive casters and two driving wheels. By the attachment position of the driving wheel related to the wheelchair frame, electric wheelchairs are divided into two types of drive systems such as front-wheel drive and rear-wheel drive. Each electric wheelchair has advantages and disadvantages about the operability and maneuverability. Especially, in the front-wheel drive, the wheelchair frame is moved in right and left direction in spite of commanding the straight motion. In this paper, we validate the cause that a front-wheel drive sways in right and left. Therefore, we built a simulation model and compared it with experimental results.

In recent years, it becomes difficult to care in constant attendance on each disability person. So the caretakers cannot have many time for movement support. Therefore we paid our attentions to the movement support for disability person who uses an electrical wheelchair. We thought that the expansion of moving area by using a robot arm on the electrical wheelchair. For example, it push a button of the elevator. In this report, we propose a controller. A proposed control method is made a database by using the inverse kinematics. And proposed controller is composed air pipe and control stick. We show that the experiment result of pushing the button by using the robot arm on the wheelchair.

Amid trends toward aging populations in developed nations, the number of people requiring nursing care has increased markedly. Slips and falls during ordinary daily activities are a common cause of fractured bones and muscle injury. Several studies have analyzed the movements produced by artificially generated slip and fall stimuli, but few have investigated these stimuli. We analyzed lower-limb motion following a slip and fall stimulus produced using a pulled free-walking system consisting of a controllable split-belt treadmill, where a speed difference between the belts could be applied to produce a slipping motion. In three male participants, we established slip motion by applying acceleration in the sagittal plane direction of the right leg immediately upon contact with the treadmill. Each participant demonstrated a different recovery method from falling.

Generally, children develop their ability to move as they grow, and gain various experience. However, handicapped children often can't move by themselves and lose a chance of some experience. We have developed some movement support equipment for handicapped children. In this paper, our attentions are concentrated on the seat of the movement support equipment. Usually, the seat of the wheelchair is fixed. So handicapped children can't approach low and high place. In this investigation, in order to enrich children's experience, we develop a unit of turning and lifting seat.

In the aging society of the future, as being the lower limbs disorders and decreased in physical strength, the number of those who need the device and the system that assists walking is expected to increase. More and more robot technology is applied to the nursing and social welfare. As for the electric wheelchair used now, the point that should be improved on correspondence to the serious illness object person (Hands and feet are handicapped) and the safety has been left. In the purpose of this research, the omni-wheel mobile walking assistance robot and the its interface controlling the motion patterns are to be developed. This paper describes the outline of walking assistance robot and analysis results of the motion sensing patterns.

Mentally and physically handicapped persons mainly live only on their beds, and have very few opportunities to go and see outside of a facility. Technologies of virtual reality have possibilities to enhance their quality of life, but such approaches have not been reported enough. Therefore, we have investigated the way to recognize intentions of them, and stimulate senses of feet. We developed two types sensors for finger and face motions to detect users' intention. Several kinds of games were used to motivate user's motions. The results shows the evidences of the intentions for two out of five subjects. Additionally we proposed electric stimulations to enhance the feeling of walking. Preliminary experiments for a healthy subject were conducted. As results, the subject could discriminate two different patterns for a front and back walking.

This paper proposes a novel control method which incorporates an EMG pattern classifier and a vision-based object classifier to control various motions of an electric artificial arm. The deep convolutional neural network is adopted as the object classifier and the posture of the electric artificial arm is controlled based on its classification result.The EMG signals are also used for controlling the phase of motion. To verify the proposed control method, a validation experiment was executed with 22 target objects. The 55 images for each target object were collected on the Web. The result revealed that the proposed method has high potential to control the various motions of the electric artificial arm.

This paper designs and evaluates a pair of walking assistive devices based on the arc foot of a passive walking robot. We aim to enable elderly people to walk with less muscular strength. This device is a kind of shoe that has an arc-shaped sole designed in order not to occur speed loss when walking. The arc-shaped sole substitutes for the ankle joint of a human. In addition, RoS-shaped sole and improved-RoS-shaped sole were designed. We evaluated the effectiveness of the assistive devices using an electromyography and a motion capture. Through experiments we confirmed that those soles are effective for the calf and the improved-RoS-shaped sole is the best in terms of the muscle load and the stability of the body balance.

We propose a pair of step-climbing units for a standard manual wheelchair. The target is a wheelchair user who has no disabled upper limbs and hopes independent life without caregivers. When traveling by car, it is easy to load them because their weights are light and they are not attached to the wheelchair. These devices are used combining with a pair of mobile slopes and move on the slopes. Therefore, they produce propelling forces to the rear wheels of a wheelchair .The shape is rectangular solid, and each unit comprises a DC motor and a crawler belt. We also discuss the controller using position and electric current data. Outdoor experimental results of climbing up two steps, which height was 18 cm each, confirmed effectiveness of the design.

There exist people who can't transfer on their own and need help for the move from a sitting posture to other sitting posture. However, many of them want to transfer without assistants. Therefore, we developed a robot that assists them to transfer on their own. The convention robot was not able to assist the people who cannot hold sitting position on their own. In order to increase users of proposing self-transfer assist robot, it is useful to realize the transfer of supine people, who can't keep the sitting position by themselves. In this investigation, we improved the mechanism of the arm part of the transfer robot and realized motions of the body hold part, which are used in the sitting up assistance to the sitting position at the end of the bed from the supine position. The proposing sitting up motion is constructed by the turning motion and the rising up motion.

In this paper, we suggest a body weight support system using rubberless artificial muscle. This system reduces the burdens on lower limbs by hanging a person with rubberless artificial muscle. We conduct the walking experiment and acquire EMG signal. After that, we confirm about the influence to give the muscle. From the above-mentioned result, the realization of a system performing body weight support appropriately corresponding to the movement of the person is possible by indicating the procedure that we suggested.

McKibben Pneumatic Actuator (MPA) is one of soft actuator. This actuator converts air pressure to tension. Lightness and high power density is charactoristic of MPA. MPA is called Pneumatic artificial muscle, used for the robots which imitate creatures, or rehabilitation equipment of limbs. MPA robot can achieve dynamic movement for example jumping and walking. MPA robot also can make steady movement by simple control. Therefore it is thought that MPA has the feature that stabilizes robot's motion. But it has not been studied thoroughly what charactor of MPA stabilizes robot's motion. To clarify the MPA feature that contributes to the realization of stable dynamic motion, we focus on jumping motion as an example of dynamic motion. We made a 2-dimension legged MPA robot and confirmed jumping of the developed robot with step inputs to MPAs. Next, We confirmed continuous jumping by periodic input and examined the relationship between the input period and jump height.

In recent years, Japan faces the issues of a super-aging society, population decrease and shortage of young workers. A robot that contact with people must be safe, light weight, and flexible. Therefore, we developed a device using a pneumatic cylinder to support a patient's upper limb motion. This supporting device has two modes corresponding to livelihood support and rehabilitation. Now, we are developing meal support mode using EMG to avoid muscle weakness as a new mode. In this paper, we reported the meal mode.

Walking is indispensable in daily lives especially for elderly person. Due to the again, their tibialis anterior muscle deteriorate and their dorsiflexion angle become small. Consequently, they tend to easily stumble and fall down. In this study, we develop walking support shoes for elderly person to support their dorsiflexion motion in swing phase by using wearer's weight. Concretely, the compressed pneumatic energy is transferred to the potential energy of a spring and the restitutive force of the spring is used as dorsiflexion moment. The validity of the proposed shoes are verified.

In the X-ray examination, pushing the stomach makes barium spread, then clear fold image and lesion of stomach can be taken. But, the pushing device for prone position is not implemented on conventional stomach X-ray systems. The inspection time becomes longer because the adjustment of the pushing quantity and the pushing position is difficult by the conventional technique. In this research, the moving mechanism for pushing position using the McKibben type artificial muscles has been developed for the purpose of shortening of the inspection time and reducing of the burden on patients. By controlling the length of artificial muscles which are attached to four places of the abdominal push mechanism, the pushing position is adjusted. We observed pushing force loading on the abdomen during fundamental experiments using the device, then the movement of the pushing position was confirmed.

Recently, many devices driven by pneumatic have been developed. Generally, they need large air compressor to obtain compressed air. However, such large and heavy pneumatic power source prevent such devices to be portable. Thus, in this paper, portable pneumatic power source using chemical reaction of sodium hydrogen carbonate and citric acid is proposed. Carbon dioxide generated in the chemical reaction is used for compressing air. Both sodium hydrogen carbonate and citric acid are generally used for cleaning, and it is cheap and non-poisonous. In addition, an experiment is conducted to verify effectiveness of proposed power source.

There is an input saturated phenomenon in the peculiar problem which is at the time of air pressure control. It makes degradation of the servo characteristics and a decline of the control performance. When doing posture control which considered input saturation by the preceding study, the problem such as the control performance falling has formed. By this study, we purpose to control system is reorganize, Improve input saturation and control performance doesn't fall.

The rehabilitation devices help to recover physical ability of patients for keeping Quality of Life. This study aims at developing a potable rehabilitation device which can be safe to use while holding it. In the previous study, the flexible spherical actuator using two ring-shaped flexible pneumatic cylinders was proposed and tested. In this paper, to measure attitude of the device, a flexible pneumatic cylinder with built-in wire-type linear potentiometer was proposed and tested. In addition, to decrease consumed air of the cylinder for portability, a hybrid flexible actuator that combined the cylinder with DC motor was proposed and tested. Position control systems using both actuators were proposed and tested. As a result, it was confirmed that the tested sensor could measure the displacement of cylinders and the position control using both actuators could be realized. The relatively long-period driving test using small-sized tank and tested hybrid actuator was also executed.

This paper describes method for hanging for pipes and lattice such as air conditioners using UAV. Recently UAVs are expected to utilize for information gathering and work at high altitude. Because continuous flying expends a huge amount of energy, attaching to wall and ceiling by using adhesion or absorption is effective function for saving energy. However, in factory or plant, wall and ceiling often are covered by pipes and lattice, using adhesion or absorption is difficult. Therefore, we propose the semi-active gripper which is pipes/lattice attachable, light weight, and energy saving. Then we show the effectiveness of our method through experiment.

Laparoscopic surgery has been widely conducted for reduction of patient’s burden. To ensure necessary vision and space under laparoscopic surgical environment, a hand-like device which can grasp organs are needed. In this paper, we describe the pneumatic-driven three-fingered hand type device with a wrist joint we developed. Each finger consists of two machined springs as flexible joint. Super-elastic alloy bands are implemented in the middle of the joints of the fingers so that the finger exerts enough grasping power to an object. The wrist consists of a flexible joint and a super-elastic round bar at the center as a backbone. The pneumatic driving system for the hand composed of nine pneumatic cylinders. We developed a dynamic model and confirmed to be capable of independent driving of each joint.

While many researchers have developed robots with McKibben pneumatic actuator (MPA) in previous studies, it has not well verified how do their properties exhibit stable motions from its simple structure. In this paper, we investigate standing stability of a 2-DOF legged robot driven by two pairs of MPA. After deriving stability conditions for the standing posture of the robot, we analyze the relation between stability conditions and combination of input pressures. From the result of analysis, we derive the design method of input pressures in order to realize various equilibrium postures. Moreover, we show the area of input pressure that satisfies the stability conditions.

This paper describes a new fluid powered manipulator for healthcare robot. It is possible to slip in the under body load in using air pressure, we propose a flexible manipulator capable of further assist the care recipient of repositioning by performing the operation in the human body under, this manipulator examined the design approach of the two mechanisms of the slipping mechanism and the bending mechanism constituting performed. And from the slipping experiment and supine to the under body load to roll over the operation assist to the lateral decubitus position and conducting experiments, we showed the effectiveness of the care support of this manipulator.

Recently, it is reported that the number of fall down accidents in elderly people has been increasing along with the progress of aging society. The main factor of fall down accident is the gap of the center of balance from declining in physical performance. Elderly people need to recover the declined in physical performance to prevent the fall down. One way to prevent the motion, it is walking training because it can do with low-stress. Then, we focused on the shoes which is used frequently and we develop the walking training system using the high-performance shoes. In this study, we developed the high-performance shoes which has two systems. One is the visual showing system that can see the walking state in real time, the other is walking assist system using pneumatics to lighten the burden that imposed on the body.

Electro-hydrostatic actuators (EHAs) are hydraulic actuators with high power-to-weight ratios that exhibit low energy loss. However, methods for identifying characteristics and parameter have not been fully established because of a number of nonlinear factors such as static frictions of hydraulic systems. Since EHAs are driven by servo motors and hydraulic motors on the load side, the actuators are expected to experience sympathetic vibrations. We apply a feedback modulator for the purpose of the friction compensation to make identification of characteristics possible experimentally. This study proposes to apply a two-inertia model and verify the dynamic characteristics.

In this study, we aim to develop a soft robot which can propel in sand smoothly by travelling wave locomotion. To move inside the sand, sufficient amplitude wave needs to be generated by the propulsion mechanism. In this paper, we propose a new pneumatic bending actuator which has large power and displacement of travelling wave. By connecting these actuators in series, a soft cord type robot with undulate propulsion mechanism can be realized. Through propulsion experiment, we stumbled on that at low pressure the robot can only move in the same direction as wave travelling direction, while at high pressure the robot move in opposite direction. To encounter this problem, we introduce two different propulsion principle, named propulsion by propagation of strain in low pressure and propulsion by counter force in high pressure. By utilizing this two propulsion principle and design the middle part in thicker structure, we can improve the travel length and propulsion velocity of the robot

Robots using hydraulic actuators perform in environment cohabiting with humans. Flexible operation and accurate detection of the external force are required to robots in order to work in safe. Backdrivability, which is an important characteristic to assure safety can be improved by using electro-hydrostatic actuators (EHAs). Although external force is estimated by pressure sensors, estimated force includes energy loss. In this paper, a reaction force observer is applied to an EHA. The proposed reaction force observer considers the energy loss in the non-linear elements, such as friction and backlash. In addition, experimental results showed an improvement of the reaction force estimation accuracy.

An adhesive mechanism using suction cups have features of simple structure and light weight, therefore the mechanism is often applied to the wall climbing robots. However the mechanism is difficult to adhere on convexconcave walls. Although by integrating many small suction cups as the adhesive mechanism, adaptability to convex-concave walls can be better, the system becomes larger and heavier, because each suction cup needs a valve for controlling the applied negative pressure. In this study, novel passive soft valves which lead to reduction of total size and weight for the adhesive mechanism have been developed. The developed valves are made from rubber material with diaphragm structure, and are driven by fluidic flow difference between adsorption and non-adsorption suction cups passively and then the valves corresponding to non-adsorption cups are closed, therefore leakage can be prevented automatically.

The goal of this study is to develop an artificial micro muscle in which a tiny compressor can be installed. Pneumatic actuators, such as pneumatic artificial rubber muscles (PARMs), have been widely used in many industrial and research applications because they are compact and lightweight. However, the compressors driving such actuators are relatively large. To solve this problem, the authors have been researching soft actuators driven by the gas-liquid phase change (GLPC) of fluorocarbon. In this research, PARM driving experiments utilizing the GLPC were conducted, and a PI control system was built to test step response of the actuators. The experimental results show that a time constant of 0.26 s was achieved when the pressure was increasing from 0.3 to 0.35 MPa.

This paper reports development of all mechanics power assist device driven by Rubberless artificial muscle. This device is designed considering with human’s natural movement and simplification due to configure all the mechanics. In this report, we suggest how to assist the movement of human, and we confirm the usability of this device experimentally.

In this study, we have been researched a very lightweight soft actuator with a folding structure made of plastic films. This actuator has several unique characteristics which are very lightweight, flexible, low-pressure drive. Some applications such as the wearable robotic and life support robots are expected. However, the force characteristics and the design method of the force don't make a clear. Because, the dynamic model of this actuator is complicates by wrinkles of pleated structures. In this paper, we focused on both the folding amount of a pleat part and the actuator size. We defined the pleat part to a rotational spring of variable stiffness. It is an object to establish a design method by deriving a static force characteristic experimentally.