Recently, aging of the population progresses with increasing speed. In this research, we have proposed an MR fluidbased Gait-assist cane for elderly people and have developed a prototype. The developed gait-assist cane has three legs and the compliance of each leg can be controlled independently. It improves the walking stability on the irregular terrain. Experimental results illustrate the validity of the proposed system.

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In this research, we are developing a novel intelligent wheelchair based on the passive robotics. In this paper, we propose a driving assistance system according to the slope angle in environment. Since the road gradient there are various, travel control can respond to each is important. Important points are compensates the fact that with a tilt angle sensor, to measure the angle of the variable slope, and by controlling the servo brake, the effect of gravity varies depending angles, an important point is the driving support algorithm. The effectiveness of our proposed system is verified by the experiments with our wheelchair.

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Wheelchairs have been typical mobilities for lower-limb disabled patients, however, long-term use of them have caused disuse of lower-limb and over use of upper limb. A cycling wheelchair was introduced as a solution to these problems. As relying on healthy part when hemiplegic patients arc riding the cycling wheelchairs is discovered in the investigation, over use of healthy part in daily use of the cycling wheelchair is another problem. Still more, for patients who are not able to bend one leg because of the other side either is stiffened of the knee joint or physically not exists, the cycling wheelchair is hard to ride with one leg. For the second step, crank torque during one-leg-pedaling is discussed and a pedaling assistive control is proposed.

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We previously proposed a biometric technology that uses skin surface deformations of amputated upper limbs. In this technology, an input device containing a strain sensor is pasted on the forearm and reads skin surface deformations caused by forearm twist motion to gain an input signal. In this study, we changed the input device containing the strain sensor to an input device containing a bending sensor and developed an electric prosthesis with the device.

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In this study, we develop a robot sensor system that can recognize a person and follow it. The sensor system is composed of multiple Kinect sensors, we call it "Multi-Kinect". Since the field of view of a single Kinect sensor is narrow, this sensor makes it wider by using three Kinect sensors. Furthermore, this sensor can identify a person and re-recognize it by image processing when an occlusion occurs. Herewith, an autonomous mobile robot with this sensor accomplishes a human detection and follows the specific person.

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For an autonomous mobile robot, an important task to accomplish while maneuvering in outdoor rugged environments is terrain traversability analyzing. Due to the large variety of terrain, a general representation cannot be obtained a priori. Thus, the ability to determine the traversability based on the vehicle motion information and its environments is necessary, and more likely to enable access to interesting sites while insuring the soundness and stability of the mobile robot. We introduce a novel method which can predict motion information based on extracted image features from outdoor university campus environments, to finally estimate the traversability of terrains. A wheeled mobile robot equipped with an optical sensor and an acceleration sensor was used to conduct experiments.

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This paper presents a target tracking system for a mobile robot in both indoor and outdoor environments. A stereo camera, which is robust to sunlight and illumination changes, is used. Human regions in images are detected from 3D information. Using color information, a target region is discriminated from the detected human regions. Hue and saturation are chosen as features robust to illumination changes. Finally, a mobile robot is controlled based on the 3D information of the detected target region. The effectiveness of the proposed system is verified through human following experiments in both indoor and outdoor environments.

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To correct radial distortion of camera lenses, fitting of polynomial model to the distortion is commonly done. Although approximation of radial distortion using low degree polynomial model is sufficient for simple optical structure lens, some kinds of super-wide-angle and low-distortion lens which have complex optical structure cannot be approximated sufficiently by low degree polynomial model. This paper describes the camera calibration method for such lenses using higher degree polynomial model. First, the application of the model to distortion design of super-wide-angle and low-distortion lens is provided. Second, the experiment on calibration of the real lens with the model is presented. As a result, more accurate fitting to radial distortion is done by using higher degree polynomial model.

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The purpose of the study on wearable power assist devices is to develop support system for those who require care. The power assist device is get heavy when the degree of freedom increases so as to prevent disturbing the movement of the human. The purpose of this study is to extract the major modes of human meal behaviors for design of the light weight power assist device by calculating the optimal degree of freedom through mode analysis. Measurement of meal behavior was used motion capture. The major modes were extracted by the mode analyses using singular value decomposition method. As the results of the analyses, the both shoulders flexion and extension motions, the left shoulder adduction and abduction, the left elbow extension and flexion were identified as the major modes of human meal behavior. The results will be utilized for the optimal mechanical design of the light weight wearable assist device.

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In recent years, development of the upper limb assist device for old people and physically handicapped person. However, the exoskeleton type has a significant problem that the system will not appropriately assist human motions when upper limb assist device has no adequate assignment of kinematical degree of freedom. One of the complexity of kinematical complexity of human arm is the kinematical structure of scapula. Therefore, it is necessary to investigate the scapular complex mechanism. The purpose of this study is the design of the exoskeleton type upper arm power assist device including the significant degrees of freedom of human scapular mechanism. In this study, meal behavior of human is measured by a motion capture system and implemented mode analysis of the motion. We derived reduced and ecessary degrees of freedom in scapular model.

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It is difficult for many wheelchair users to climb a step because the front casters of a wheelchair are small. In this paper, we proposed the system for a wheelchair user to climb a step safely without manual operation. We proposed the system for climbing a step applied a wheelie motion about a five-wheeled wheelchair with a single drive wheel. We derived the kinematics model about the wheelie motion of the five-wheeled wheelchair and simulated the traction force needed to perform the wheelie motion. In some experiments, we showed the position of the drive wheel is related to perform the wheelie motion easily.

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There are many patients with movement impairment, which is paralysis caused by a brain stroke. Sufficient rehabilitative training is necessary for these patients. Rehabilitation support systems for upper limbs using force display devices are expected to quantify the effects of rehabilitative training and enhance the motivation of patients. In this paper, we describe about development of exercise bike for upper and lower Limbs.

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This research aims to develop a robot which can shoot a mobile target following a given camera work describing a space-time robot trajectory in the target's local coordinates. The robot calculates the target position using a vision and laser-based person detector and on-line modifies the trajectory to which a path planner is applied to generate a robot motion command. Since the target moves continuously moves in the image due to the errors in target detection and motion control, we post-process the captured image sequence so that the target is always at the center of image. For this post-process, we extract Harris features in the target region and calculate optical flow for the features to estimate the target motion in the image, which is then used for horizontally translate the image. We validated the proposed method by shooting experiments for several target motions.

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Autonomous navigation in outdoor environments requires self-localization capability. This report describes an application of a view-based localization method to mobile robot navigation. Our localization method uses a two-stage SVM-based localization for increasing robustness to change of weather and seasons. It also adopts a Markov localization approach for an efficient and reliable localization. In applying the view-based method to mobile robot navigation, the change of robot heading during motion may degrade the localization performance. To cope with this problem, we use a panoramic image to search a range of orientations for a matched view. Additionally, a navigation course is divided into straight courses by corner. We also deal with a corner localization by examining views corresponding to the heading before and after turning the corner. We validated the effectiveness of the method using actual image sequences.

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Mobile robots can be controlled smoothly using forward course situation in the future. The course situation is analyzed in detail through the images obtained by the cmos image sensor or something like that. In this study, the quantity of the information recognized by image processing is important and the method to make the course of a mobile robot to the target point using the visual information in the future is discussed. Fundamental experiments were performed to know the accurate dimensions and the placement of the known rectangular (line segment) target based on the transformed images of it taken by a cmos image sensor.

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By the prosperity of Internet circulation, the net mail-order firm must send out a product more quickly. To cope with this, introduction of the Automatic Guided Vehicle is pushed forward in the distribution warehouse of each net mail-order firm. It is called AGV for short. AGV is an automatic conveyance chassis. AGV is given instructions in detecting magnetic tape laid by floor and a magnetic stick, and it can run according to information from floor automatically. It plans the reduction of personnel expenses by automation and speedup of the conveyance or the automation to use this AGV for the transportation of the product in the warehouse. In this study, an image-processing module acquiring the information of the position and the information of the position gap from an image of the two-dimensional bar code acquired is developed.

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There are growing needs for assistive robots which support independent life of elderly and disabled people or help people who work at the assistance and the nursing care. We are studying on establishment of the methodologies of developing such robotic care devices. We use ICF (International Classification of Functioning, Disability, and Health) and SysML in the development processes. In this paper, we describe the concept of modeling and requirements analysis using ICF and SysML, and show some examples of the model of nursing services focusing on transfer support activities. We also show some problems to solve in order to realize the concept of our studies.

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Home Oxygen Therapy (HOT) patients need to carry the portable oxygen cylinder when they go out. However the portable oxygen cylinder seem to be heavy for carrying. I propose to a robotic cart for carrying oxygen cylinder to support HOT patients. Propose robotic cart applies compliance control to operate the cart itself easily by using handle shape interface which is usually attached to the popular carry cart, and then the robotic cart becomes to be able to follow the patients by carrying their portable oxygen cylinders. In this paper we describe the robotic cart operation.

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The demand of assistive technology will increase by the lack of caregivers because Japan is becoming aging society. The power-assisted wheelchair which assists the driving force by electric motors is expected to be widely used as a mobility support system for elderly people and disabled people. This study proposes a novel torque adjustment method to improve both the driving efficiency and energy efficiency using fuzzy inference. Some driving experiments show the effectiveness of the proposed control system.

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This paper proposes a feature value design method using dummy variable for the high-precision motion discrimination of myoelectric hand. Then the false discrimination lead to the serious accidents. Therefore this study designs the dummy variables in order to improve the discrimination precision. Dummy variables are designed particularly for some motion pairs which are difficult to distinguish. Some experiment results show the proposed method can improve the discrimination rate in all subjects.

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Aimming to design a soft robotic fish for more flexible and efficient fish-like motion by biomimetic method, we are developing a snake-like robot with body undulating propulsion using the piezoelectric fiber composite (PFC) as soft actuator by mimicking the sea snake. Due to the large deformation of flexible structure and complicated dynamics with fluid, the design method for soft fish robots has not been established, and we need to study it by considering the coupling between them. In this paper, the sea snake-like robot using PFC is developed by the analytical simulation with considering the coupling between flexible structure and fluid. The efficient body undulating propulsion based on meandering motion is realized successfully from the prototype, and its swimming efficiency is similar to the real sea snake's.

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Currently, many ships or underwater vehicles use ballast to control their buoyancy, although it is harmful to the environment. We have been developing a volume variable buoyancy control device inspired by a hypothesis on the volume control mechanism of sperm whales. We proposed several mechanisms and achieved the depth control using one of the mechanisms. As the next step of this study, we focus on waste heat of ships. Usually large ships adopt a co-generation system, in which heat are wasted. Because our proposed mechanism needs a large amount of heat, we consider that our mechanism works well in the system. First, we manufactured a prototype mechanism utilizing stretch of rubber sheet. Its shape is a cylinder, in which heated water flows. Also, we built a prototype system composed of a pump, a thermostat chamber and volume valuable mechanism, and investigated the system through an experiment.

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In this paper, we improved the capability of a human-portable underwater robot for soil core sampling. We have already proposed an underwater robot for core sampling. However, the motion efficiency of the developed robot was low. To solve this problem, we developed an attitude control mechanism in order to reduce the drag force acting on the robot. Furthermore, we also developed an automatic control system for operator support.

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Authors have been developing the underwater robot which can be used for environmental protection work in the sea near Okinawa. It is difficult to get the position of underwater robot, because GPS does not work in water. Our research field (the Okinawan sea) is high degree of transparency, so we try to develop the inexpensive measurement for underwater robot using a monocular camera. In this paper, we illustrate the measurement method and examination of the position accuracy.

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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.

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In recent years, the population of young people has been decreased due to the declining birth rate and a growing proportion of elderly people, and the elderly over the age of 65 increases. In the caregiving in the old-age home, physical burden of caregiver increases due to the increase of their work. In these point of view, we have developed a care transfer machine to reduce the physical burden of caregiver in the caregiving work. In this study, the physical stress of the care receiver that caused by the proposed care transfer machine is investigated. The measurement of physical stress is performed by using EMG. As results of the measurement, maximum muscle potential is 0.03 [mV] in riding action. Further, muscle potential in the consciously straining is 0.06 [mV]. Therefore we estimate that the developed transfer machine doesn't affect the physical stress on the care receiver through some experimental results.

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The purpose of this research is the motion discrimination by electromyography(EMG) considering the angle change of the upper arm. Myoelectric signals with another shoulder and elbow motions have the potential for causing the false discrimination, which leads to the serious accidents. Therefore this study proposes a discrimination method with linear interpolation of the training data between shoulder and elbow angles. Some experiments show the effectiveness of the proposed method.

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In this study, targeting on the early rehabilitation of handicaps, the life support system termed as REACH: Robotics Enhanced Assistant Conquering Handicaps, is proposed. This system recognizes situation and condition of the handicaps using cameras and RGB-D sensors. Based on the recognition, the system supplies optimum and individual support to each handicap. When the system receives requests of the support via control devices, the requests are converted to commands, which the robots of the system are able to execute. By realizing the commands by robots, the handicaps are supported by the system. In this paper, to simplify the robot of the system, the novel mechanism for controlling the living environment is described.

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Ocean development has actively progressed in the sea near Japan. However, in marine research, it is impossible for people to work in deep sea because of low temperature, high pressure and so on. Therefore, AUVs (Autonomous Underwater Vehicles) are expected as applications such as investigating and mapping a submarine volcano and so on. In previous researches, many AUVs have been developed, however they have to change the attitude when the robot change the direction of movement. In this research, we developed an AUV which is able to move all directions in a small space in the same as a quad-rotor helicopter.

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Housing component design of floating buoy NOMAD for lake water pollution monitoring has been presented. The housing consists of a control module, solar cell modules and a drogue module. Drogue module is sail-like object capturing the drag by flow in deep zone of lake water. Thus, in designing control module, specific consider has been paid to reduce the drag by flow below the surface. Consequently, a control module prototype which employs a hemisphere housing has been designed. The induced drag is significantly decreased as compared to the former prototype case. The flow characteristics of the designed buoy should be experimentally investigated.

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The ocean that covers 71% of the Earth's surface is the source of origin of the life and biological evolution. Furthermore, ocean plays major role in regulating the weather and the climate of the planet. The features of the deep ocean also effects on controlling the climate of the earth. In addition, lots of discoveries, abundant mineral resources, energy, marine lives, and hydrothermal vent in the deep ocean have attracted research scientists of various fields. In spite of attractive discoveries, we are still unable to get clear information about the mechanism of the Deep Ocean and ecological system, because Deep Ocean is an extreme environment that has high pressure, darkness and radio attenuation. Recently, Autonomous Underwater Vehicles (AUVs) are used in Deep Ocean research activities as a powerful tool. AUVs are enrich with various facilities that can take photographs include lifestyle of marine lives, etc. In this paper, we have proposed a method to recognize the Benthos on the deep seabed automatically for various research activities. As a result, the proposed method has shown that it can detect about 84.7% of targets in the deep ocean images and capability of recognition is about 74% of the detected targets.

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Autonomous Underwater Vehicles (AUVs) arc one of the key technologies for deep oceanic research. The working space for AUVs is one of extreme environments and very hard for human to access directly. AUV is one of solutions to access the deep ocean, however, many problems exits to be the sufficient tool. One of big problems for AUVs is the self-localization, and in order to estimate its position, the dead-reckoning is often used. The dead-reckoning method is week to disturbances from its nature of algorithm, so that we introduced Monte Carlo method in the estimation process of localization. In this paper, we introduce a goal searching algorithm based on Monte Carlo method.

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Among the Japanese women, the disease rate of breast cancer became the most highest one, over ahead of that of stomach cancer. Detection of breast cancer is implemented by both palpation diagnosis and mammography. Palpation motion requires for doctor to have a highly skilled technique. In this study, we aim at developing a palpation simulator which has an actual breat model to be touched by human in natural manner. The developed palpation simulator is composed with multiaxis orthogonal axis driven with pneumatic cylinders. Force based compliance control system in implemented to display force feeling from lump model constructed in a VR environment. The validity of the proposed palpation system are confirmed through some experiments and analysis.

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In this paper, we present a tele-operated mobile robot system for old age surveillance. The robot operates in autonomous mode in which the robots navigates in the environment and search for unusual situation of elderly people. If a patient is lying on the floor, the robot informs the user. The user switches the control mode from autonomous to haptic based user control. In the autonomous mode, the robot utilizes the visual sensor ana landmarks to monitor the entire environment. The robot is equipped microphone, speaker and monitor making it possible to communicate with the user in remote place. In addition, the robot utilizes the vital sensors to check the patient's condition. The preliminary surveillance experiments show a good performance.

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Currently, there is a big problem of aging society in the world. So, we are developing the equipment for supporting elderly people's standing-up movement. In this report, we examined operation start timing of the experimental equipment from the movement of the center of gravity, buttocks lifting, load applied to the handrail, and grip strength of the person. As a result, the timing for operation start by grip strength has the highest evaluation point, and that by buttocks lifting evaluation has the lowest evaluation point. In the next step, we will make a quantitative evaluation and establish the control method of the supporting equipment.

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This paper discusses the development of H-WAMC, especially the method for decision of the desired trajectory of leg motion generator. First of all, the desired trajectory was determined based on the motion of human knee joint and ankle joint during human walking. Next, the effectiveness of the slider-crank mechanism on the reduction of driving energy was evaluated by the comparison of the driving energy of slider-crank mechanism with the energy of ball-screw. Finally, the validity of the desired trajectory was demonstrated by the measurement of posture and grand reaction forces the human walking with and without using prototype leg motion generator.

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Authors have been developing an underwater robot that able to execute the object lifting operation. The robot has two vertical thruster that used for vertical movement control. At the object lifting operation, the thrust of these thrusters is used for lifting. We previously proposed the new mechanism "Passivity Posture Maintenance Mechanism for a Thruster", in order to use the thrust effectively and lift up an object easily. We also have already confirmed the effectiveness of this mechanism. Therefore, this paper presents to confirm about object lifting operation by the basic experiments in the sea.

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Underwater is extreme environment. So, underwater robots are employed to some tasks for human's safe. However, high-speed motion in underwater condition is occurred drag forces. In this paper, we propose a sampling device for underwater robots. It was designed as a high-speed mechanism. Because, a mechanism which it has performances higher than human make new applications. The high-speed motion is needed an energy and an efficient transmission system. We explain a design of the mechanism.

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Oceans cover more than 70% of the earth's surface and their space is 300 times larger than the space on land, and, ocean resources such as methane hydrate and cobalt rich crust exist in deep ocean. As the tools to access the deep ocean, underwater robots attract high attention, and it is important to give young generation motivations to underwater technologies. So that we are working on the outreach activities related underwater technologies through underwater competitions. In this paper, we introduce a small ROV (Remotely Operated Vehicle) and robot system using a graphical programing language MATLAB/Simulink.

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In this paper, Manta-like robot is proposed to perform the fin with flapping and feathering motion. The part of the edge of the fin having the elastic or rigid is controlled by three servo motors .The propulsion performance of the fin is evaluated by swimming number for frequency by the fin vibration. The swimming number has the maximum value for the frequency of the flapping motion. The result shows that the controlled feathering angle is important to swim for the Manta-like robot.

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A captive balloon system named InfoBalloon has been developed as a system for collecting and distributing disaster information. To support a disaster area, the captive balloon has to be stably moored. However, height, position and posture of the captive balloon are in danger of changing by wind in mooring. So it is necessary to evaluate behavior of the balloon in various wind conditions and methods of mooring to develop steadier InfoBalloon. We know the motions of the balloon are different depending on the conditions of the mooring point, so we evaluate the balloon motion of each mooring condition under changing wind direction and wind speed with the mooring simulator. Finally, we simulate rotation around the axis of symmetry of the balloon.

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This paper presents a new method to advance and to carry wired sensors like a camera inside narrow and curving pipelines, which is aimed at inspecting inside the pipelines. To fulfill this request, a Twin-tube Probe Robot is proposed. So far, it was verified through experiments that this robot was able to climb up narrow and curving pipelines. This time, a steering mechanism is proposed, realizing the curving motion with two degrees of freedom. By utilizing this steering system, this robot was successfully able to cross over obstacles by lifting up the head unit. Additionally, this mechanism was capable of selecting the propelling direction in T-shaped junction.

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When an active volcano erupts, typically, a restricted area is set around the crater for safety. However, it is important to observe inside of the restricted area for a forecast of disasters, such as debris flow. There arc some proposals of visual observation methods in restricted areas, e.g. a tele-operated mobile ground robot with cameras. However, there is no sample-return method for obtaining volcaniclastic materials from such restricted areas. Therefore, in this research, we developed two sample-return devices that hang down from multi-rotor UAV. In this paper, we introduce our developed devices, and report indoor and outdoor experiments.

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Active Scope Camera (ASC) is a special video scope for search and rescue operation, which has self-propulsion with the ciliary vibration drive proposed by the authors previously. Although the conventional ASC has running direction control functions, ASC still needs more stable direction control capability. In this paper, we propose a new direction control method using air blow. The preliminary experiments were conducted to confirm the potential and basic characteristics.

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Most maritime nation now focuses on the seabed mineral resources which are buried in one's exclusive economic zone (EEZ). Of course, Japan is no exception because it is a natural resource-poor country. But the its EEZ area is sixth largest and its volume is forth largest in the world. Basic on such background, Japan strongly needs new underwater vehicles which can work in order to contribute seabed resource exploration. So JAMSTEC has been developing new AUV "YUMEIRUKA" specific to that. In this paper, its outline and some key technologies are explained.

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Japan Agency for Marine-Earth Science and Technology (JAMSTEC) has been developing three autonomous underwater vehicles (AUVs). And one of them is "OTOHIME". The aim of this vehicle is to measures the amount of chemicals near the seafloor and observes the seafloor condition and topography. Although It is still in a developmental stage, it is soundly near completion because various tests are repeatedly conducted. In this paper, its outline and some key technologies are explained.

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Many insects can jump several times their own body length. Locusts with their powerful hind-leg can for example jump up to five times as high 250mm. We have been working on high power joint mechanism imitating locust hind-leg. The mechanism can produce a several times as much power as mounted actuator and separates normal and rapid motion by controlling the actuator force. This paper proposes fin actuator with the high power joint mechanism which can realize rapid motion of two directions. The fin actuator consist two motors with cams, two wires, one spring and L-shape link. Our analysis of output characteristics showed that the proposed fin actuator develops higher output power than mounted actuator.

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Localization under water is required for the underwater mobile robot to conduct the survey autonomously. There is a conventional method using inertial navigation system as a localization under water, however it takes high costs. In this study, we propose a laser odmetry as a localization for underwater mobile robot. The laser odometry is a method to estimate motion by tracking the laser speckle pattern. It can measure three dimensional positions and a rotation. In this paper, we introduce a principle of the laser odometry, the construction of the sensor unit, and the results of measurement accuracy experiments under water.

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This paper describes on the development of an aerial work robot with the manipulation function. Until now, a moving means of the search robot for a dangerous building has been developed by the crawler. However, the crawler is difficult to correspond to the place uneven terrain or the elevation of the ladder. In order to solve the problem, it is suggested the flying robot with a manipulation function approach to make its own access road. This time, we propose a method for door opening operation. And, through experimentation, we have verified the effectiveness of this approach to the problem.

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Robot technology is expected to become applicable to missions on rough terrain, such as rescue activities, environmental investigations, and planetary exploration. Tracked vehicles are effective against such environments because the contact pressure of the vehicle can be distributed more widely. In order to improve mobility, new mechanisms such as a serpentinetype tracked vehicle have been proposed. We previously proposed the flexible mono-tread mobile track (FMT). The first prototype called WORMY has a mechanical problem, i.e., track belt interference and derailing, when it moves flexing. This paper proposes and validates a new design strategy of the FMT adopting layered structure of its body. The layered structure reduces space between vertebrae, which can solve the derailing problem. A new prototype adopted the layered structure is developed in order to validate its mobility. We also evaluate effectiveness of passive retroflexion against obstacles.

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