Real-time image recognition at 1000 fps is realized by implementing a circuit module to calculate higher-order local auto-correlation (HLAC) features on a high-speed vision platform. The high-speed vision platform, on which the HLAC circuit module is hardware-implemented, can extract 25 HLAC features at 1000 fps from 1024×1024 pixel images. In the experimental results, high-speed projected images are recognized by using HLAC features.

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In this paper, we propose a new zoom and focus tracking system. First, a new zoom and focus mechanism for a high speed-vision is proposed. The mechanism consists of a varifocal lens and two DC blush motors. It is lightweight, and it has good performance to be controlled at high speed. Next we design a control system for a high-speed zoom and focus mechanism for a high-speed vision. In the control system, zoom is controlled by the area of a target, and focus is controlled based on SML(Sum of modified Laplacian).

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Increased health damage caused by asbestos has become a problem recently. Removal of asbestos from building materials or rendering it harmless are common means of alleviating asbestos hazards. In the process, a judgment of whether asbestos are included in building materials is required. Complying with an official method, particles and asbestos in microscope images of samples made from pulverized building materials should be counted to judge whether the samples contain asbestos. This task is performed manually and requires enormous amount of time and burden. Asbestos containing judgment support system with image processing is being developed to improve its efficiency. However, low brightness particles must not be detected because of judging not harm but harmless, detecting low brightness asbestos is difficult. This study is intended to establish a method is also able to detect low brightness asbestos, we propose an asbestos detection method focusing on frequency distribution of the image.

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This paper proposes a weighted feature selection technique for visual servoing with occlusion recovery. The proposed control algorithm selects a set of correctly extracted image features, and it estimates all image features from the correctly extracted image features. The control input signal is calculated by using the selected image features with weight in order to reduce discontinuities caused by the change of the selected set.

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This work describes the development of a stereo vision system used as a 3D sensor to detect obstacles in outdoor environments. Camera captures frames with high sampling rate which makes the stereo vision capable for 3D scanning of mobile obstacles. We implemented the stereo system with two IEEE1394 cameras using wide angle lenses and casing developed using rapid prototyping. We use a fast stereo algorithm provided as a function in OpenCV to generate highly reliable disparity maps calculated with sub pixel accuracy. From the disparity map we reconstruct a 3D environment, and then filter out the objects according to their height from ground level up to 2 meters in order to detect only the objects that could block the robot's path. The filtered objects are then clustered using a blob extraction technique. From various experiments we confirmed this system to be capable of detecting obstacles. This system uses resolution of 640x480 and is capable of reconstructing the 3D environment and detecting obstacles at a rate of 20fps+.

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Successful multi-target tracking requires locating the targets and labeling their identities. For the tracking systems, the latter is more challenging. In this paper, we propose a method for multiple persons tracking using multiple cameras and laser range finders. Our method estimates 3D positions of human body and head, and labels their identities. The method is composed of multiple particle filters, and each particle filter tracks each person correctly by integrating information from laser range finders and the target-specific information from multiple cameras. Integration of these two types of sensors enables complement of each weak point and the correct tracking of the target. Moreover, we develop a new particle filter framework that tracks the human head by using the estimated human body position simultaneously. Our experimental results demonstrate the effectiveness and robustness of the method in multiple persons tracking.

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In this paper, an outer shell type 2 DOF bending manipulator using spring-link mechanism is presented. In medical robotic applications for endoscopy, a small-sized multiple DOF manipulator within medical treatment devices (such as endoscope, suction tube, electric knife and so on.) will be beneficial. The spring-link mechanism is a combination of a fiat spring and a rigid link with a passive joint connection. The outer shell bending manipulator is composed by four spring-link mechanism. By locating the four spring-link mechanism around the manipulator, it is possible to place medical devices inside of the manipulator. The advantages of the manipulator comparing conventional manipulators are: high rigidity, high precision and outer shell structure.

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This paper describes the development of force feedback method for a remote laparoscopic surgical system. We developed a remote laparoscopic surgical system and have been conducted several time of tele-surgery experiment over the conventional network infrastructure. However, in this surgical system, it is difficult to configure appropriate power output from lack of sense of force. Consequently, we apply force feedback to a remote laparoscopic surgical system. We measure force applied on a tip of the forceps by measuring force applied on driving shafts of a forceps. Furthermore, we conducted a task evaluation experiment of force feedback through remote operation.

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In this paper, a separation model for blunt dissection simulation of a brain surgery is discussed. In the separation model, fracture behavior of brain tissue and its representation in the simulation are important. A brain tissue is modeled by using finite element method. The finite element model is composed of three layers in which a connective tissue model is sandwiched between two brain parenchyma models. In order to represent the fracture behavior in the finite element model, when the principal stress generated at an element exceeds its maximum, the element is removed from the model. In order to validate the separation model, fracture experiments are performed using a agar. The experimental results are compared with the fracture simulation results.

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Endoscopic Submucosal Dissection (ESD) is type of a minimally invasive surgery. In this surgery, it is difficult to ensure visual field of edges of the excised tissue when doctors perform to detach submucosa. We have been developing a surgical tool that can hold up diseased tissue with a vacuum contact parts which doesn't make mucosal tissue damaged and enable to inflect automatically. In this paper, we had experimented the retention force of surgical tool developed here for gastric mucosa tissue of pig. Experimental results indicated that this tool was able to produce the retention force by using a Bellows type vacuum pad, and the retention force was independent of the plicae size and prevent some damages to the mucosal tissue.

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We have proposed a novel method to produce biological models using polyurethane elastomer, which has high photoelastic coefficient. And a method to analyze stress states on the model by circular polarized light method. In this paper, we propose stress measurement on biological model by image reconstruction which is a stress measurement method using photoelastic effect. With this method, the cross section of the model was reconstructed accurately by the image reconstruction processing. And, each pixel stress states of not only principal shear stress, but also each stress difference and shear stress can be measured. Consequently, it should be valuable for various applications not only surgical simulations but also hemodynamic studies and pathological studies.

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Research concerning a control method intended for a surgical robot, which prevents the overload of fragile tissues is shown in this paper. In particular, we proposed that the simulation based parameter setting method to ensure the robustness of the performance relative to the variation of the organ stiffness parameter. The simulation and experimental result suggests that our control method helps to prevent stress overload and that the proposed parameter setting method is effective in realizing the robustness relative to the variation of the organ stiffness parameter.

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In recently year, disparity in medical treatments between different domains is a serious problem of the elderly dominated society. So realization of robotic tele-surgery would be expected for elimination of the disparity in medical treatments between different domains. For the development of intra-operative assisting system, a clarification of the relation between network disorder and operability during a surgery is required. This study aims to evaluate operability quantitatively under the delay environment and propose required conditions of surgical assisting system. In this paper, the three kinds of simulator are developed and the operability of gripping motion under the delay environment is evaluated with this integrated simulation system.

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Nowadays, an Objective Structured Clinical Examination (OSCE) has been proposed as a modern type of examination often used in medicine to test skills. OSCE is a practical exam in which students are evaluated by experienced examiners using a check list. However, the examiner lacks of information which cannot be obtained through the simple observation. In this paper, we have proposed the development of a suture training system which provides quantitative information of the task. In particular, the details of the Waseda-Kyotokagaku Suture No. 2 Refined II (WKS-2RII) are given. Experiments were carried out to confirm the effectiveness of the proposed training system and the proposed evaluation function.

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In the teleoperated minimally invasive surgery systems, measurement and display of sense of force to the operator is a problem. In order to carry out safer and more precise operations using robotic manipulators, force measurement and operator feedback are very important factors. We have proposed a pneumatic surgical manipulator that is capable of estimating external force, without the use of force sensors. However, there was a problem that the surgical manipulator could not work well in the abdominal cavity due to mismatch of working space between them. Also, the force estimation had a sensitivity of only 3[N] because of inertia and friction effect. In this paper, we newly developed an improved model of the surgical manipulator IBIS IVto solve this problem. We conducted some experiments including in-vivo experiment and confirmed that the effectiveness and improvement of the manipulator.

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We have developed the surgical robot system with heart-beat canceller for coronary artery bypass grafting. This robot system accomplishes the compensation by synchronized with heart-beat. But the ability of synchronization is not enough because of transfer element backlash. Therefore the purpose of the research is a design and evaluation of the control system for synchronization at high speed. We designed the control system using P-D controller and evaluated frequency response and then we did synchronization experiment. In the result the synchronization was not achieved because the error of heart-beat measurement was large. So we need to reduce this error in the future.

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In this research, we focus on the method of rehabilitation with stretch reflexes for the hemiplegic upper limb in stroke patients. We propose a new device which utilizes electromagnetic force to evoke stretch reflexes. The device can exert an assisting force safely, because the electromagnetic force is non contact force. In this paper, we develop a support system applying the proposed device for the functional recovery training of the hemiplegic upper limb. The results obtained from several clinical tests with and without our support system are compared. Then we discuss the validity of our support system.

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We proposed the rehabilitation program that treated the contracture turning attention to the sense of the paralysis finger by using perception support RT that fed back biotechnology to non-paralyzed side and prevented the sensation of motion on the paralyzed side that had been proposed last year to the hemiplegic subject. Actually, when the rehabilitation program was applied to the hemiplegic subject, the utility of rehabilitation that used perception support RT was suggested because postponing the posture maintenance time was seen while training and range of motion also showed the extension.

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Hemiplegia patients will more or less lose their accuracy of position sense. Therefore, their paralyzed-side-motion is inferior to that of non-paralyzed-side. We thus aimed at the symmetry motion and proposed a rehabilitation program and a new rehabilitation-assisting RT device that bio-feedback their differential. We performed this practice to two chronic hemiplegia patients once in a week, and as a result, differential in joint angle of symmetry motion decreased significantly after the practice. In addition, we verified that this efficiency sustained at least one week on one patient. And so, these results raise the possibility of curing the patient's paralyzed-side-motion.

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Until now, some rehabilitation robot systems for upper limbs were developed by many researchers. It is important for designing a rehabilitation system, which trains in the 3-DOF spaces because the upper limbs of human's works in 3-DOF spaces even expect for the wrist. However, there was few rehabilitation support robot system for 3-D training with high safety. Therefore, we developed the quasi-3-DOF rehabilitation system; PLEMO. The quasi-3-DOF rehabilitation system has 2-DOF force-feedback function in working plane but the angle of the working plane can be adjusted. PLEMO system does in the middle of clinical evaluation. The development objective and mechanism of new handle, which was developed to improve the efficacy of the training, are reported and compared with the performance of the former mechanism; moreover, software compliant with new handle is presented and its training efficacy to stroke patients is discussed.

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In this paper, a surgical motion base for neurosurgery is presented. By introducing a new parallel mechanism, high rigidity and accuracy can be implemented by composing remote center of motions and a linear motion into a parallel mechanism. The robot can be easily mounted on a conventional surgical head frame. A 3 DOF passive mechanism is introduced for adjusting the robot position on the head frame. Mechanical evaluations are conducted and reported in this paper.

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Endoscopic surgery is minimally invasive and presents many advantages for the patients such as reduced pain, small scar, and quick recovery. However, it has a problem such as difficulties in cooperation between the surgeon who mainly operates surgical instruments and the camera assistant who operates the endoscope. To solve this problem, the automatic endoscope positioning system that holds and automatically operates the endoscope instead of the human camera assistant has been actively studied all over the world. However, it is difficult to make an accurate model of actual endoscope operation during surgery. In this paper, we propose a novel endoscope positioning algorithm inspired by biological systems dynamics. Moreover, we propose an evaluation function in which an actual endoscopic procedure is appropriately reflected through gallbladder removal simulations, and a new algorithm is completed.

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The clinical target of this study is intrauterine patch coverage of fetal myelomeningocele. The collagen patch is supposed to be stabilized onto the fragile fetal tissue during the laser fixation process. In this study, a patch-stabilizer using wire driven mechanism has been developed for precise force control on the patch without damaging fetal tissue. The diameter of the patch-stabilizer's shaft is 2.4[mm] and the stabilizing part holds collagen patch with diamond shape mechanism using wire driven. The patch-stabilizer is moved by the ball screw to stabilize the collagen patch and the stabilizing force is estimated with the wires tension. In this paper, the wires tension is controlled less than 0.4[N] and the stabilizing force is small enough to stabilize the collagen patch onto the fetal tissue.

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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. Moreover, this paper presents the evaluation based on the motion direction in FNF mode test with Robotherapist.

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This paper proposes a new biofeedback system that enables hemiparetic patients to notify the possible room to weight to the paralyzed-side body and reduce any unexpected muscle tense caused by the anxiety against toppling. To let patients to overcome fight-or-flight response when walking produced by paralysis, we designed a rehabilitation training protocol using a biofeedback device, PALTY that steadily gives a small increased target between each session referring to exposure therapy which is a cognitive behavioral therapy technique for reducing fear and anxiety responses, then enabling them to getting to weight to the paralyzed-side body. Evaluation experiments indicating a hemiparetic patient got to make the increased duration time to weight to the paralyzed-side body due to the BF supportive information confirm the effectiveness of the proposed system and protocols.

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The authors are developing a leg robot as educational tool for physical therapy training. The leg robot can simulate some problems of a knee joint, such as contracture, rigidity, spasticity and so on. However, there are two kinds of differences between actual knee joint mechanism of human and the knee joint mechanism of the previous patient robot. This paper presents a leg robot having a new knee joint mechanism with rolling, sliding and coming off. In the new knee joint mechanism the range of motion of the rolling motion becomes wider, and the coming off motion can be controlled.

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In our country the number of handicapped people is estimated to increase because of sickness and injury, etc. Because of their physical handicaps, activities of daily life (ADL) will become difficult. So, handicapped people require training for rehabilitation to recover their ability to use upper limbs. In rehabilitation training, the patient and the occupational therapist (O.T.) train together. The O.T. demonstrates and facilitates motions that give a constant load to patient's limbs and moves their limbs, slowly repeating the flexion and extension. The machine can often substitute for the O.T. 's motion in rehabilitation. Therefore, we developed an upper limb rehabilitation support system using a pneumatic cylinder. In this paper, we reports the characteristics and the rehabilitation support functions of the system.

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This paper investigates the role of reflex circuits and biarticular muscles on reaching behaviors. Both mechanisms are impremented on a 6dof musculoskeletal arm driven by McKibben pneumatic actuators. Experimental results show that the proposed reflex circuit realizes load compensation and biarticular muscles contribute in realizing a straight reaching motion with bell shaped velocity profile.

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Haptic object recognition by a robot hand is essential for adapting to human environment because of its role in multimodal sensing and detecting affordance. An intrinsic difficulty of such recognition is due to its locality. Tactile information is local compared to vision, and slight difference in contact condition dramatically changes the sense. We hypothesize that the structure of the human hand is the key for avoiding the difficulty. The robot hand with the adaptive design of the human hand, covered with soft skin with multiple tactile receptors, is developed. The hand performs robust haptic recognition through repetitive grasping by virtue of its adaptive design.

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In this paper, we propose that the general definition of mind is "hiding active regions" in the object observed when it expresses a conventional behavior and verify that there is mind in robots and /or machines by revealing the existence of the hiding active regions in them. We also suggest that the characteristic function of mind is to elicit "unconventional behaviors" in unusual environment. These ideas may change the way to identify robots as human beings from Turing test to the experiments to elicit unconventional behaviors and bring essentially organic relationship between human beings and robots.

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In this paper, we develop an intelligent walking support machine with the safety devices, which provide a patient with partial body weight support and prevent the patient from fulling. The constant force springs are used in order to provide the patient with partial body weight support. The powder brake, which can control the torque, is used as the device to prevent patient's falling. We propose a new control method to prevent patient's falling When a patient normally uses this support machine, the machine provides the patient with partial body weight support. After the machine detected the patient's full, the machine prevents the fall by applying the impedance control to the powder brake. The usefulness of the walking support machine is experimentally examined.

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We have developed a rehabilitation aid system by employing a non-contact human walking sensing technique in order to visualization of progress in walk rehabilitation. This system enables the stable and perfectly non-contact measurement of human walking, which was impossible using the conventional methods. A study has been carried out on a normal subject by fastening a left leg onto a splint with bandages. As a result, it is possible that a rehabilitant and a physical therapist know objectively the pace of progress in walk rehabilitation using this rehabilitation aid system.

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A hand motion recognition system using forearm SEMG is developed. In this system can recognize 18 hand and finger motions from the change of forearm SEMG. However this system cannot estimate the strength of muscle. So, the estimation method of muscle strength was experimentally developed. In this method, muscle strength was estimated using linear approximation for the amplitude of SEMG. In this paper, we evaluate this method.

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Human dynamical balancing capability is affected by physical exercise and aging. Although the deterioration of this capability sometimes causes accidents and falls, the precise mechanism of this capability has not been clarified. Thus, we are creating a measuring and training device to determine the level of this capability, improve patients' physical condition, and help them prevent losing any further physical strength. In this study, we designed and created a prototype for a new device that is different in structure from our previously developed device in order to enhance the multiplicity of training. The new device is based on use of a pair of small-sized "two-parallel wheel sub-vehicles," and these two sub-vehicles can be connected to each due to the computer control. Through experiments, we investigated the behavior of trainees with this device, and examined the possibility of the device being used for measuring and training purposes.

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In recent years, we are anxious about a global water shortage. The main cause of water lack is the surplus use of the water resources by the human. Therefore, the approach on positive water saving is needed for resolution of the water shortage. On the one hand, there is much water which is used to toilet washing at general home. Consequently, it is necessary to develop the sewage disposal system that functions under water saving. We focused on the bowel peristalsis as a model of the kind of mechanism which can convey the sludge even with the little water. In this paper, we suggested two mechanisms which unitize the whole pump, and compared the capability of them. Additionally, we made the peristaltic pump of six units with superior mechanism, and had liquid transportation experiments.

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In recent years, the robot has been in the field of medical scene and human life. These robots operate in an environment close to human, it is necessary to achieve the coordination of work and ensure the safety of people, when these robots contact with humans. Therefore, these robots be flexible and lightweight, it is desirable to have the characteristics a close to human behavior. For this reason, we have studied and developed an artificial muscle actuator using straight-fiber-type artificial muscles derived from the McKibben-type muscles. In this study, we propose a new method of joint stiffness control to make a delicate operation on the artificial muscles manipulator, consider the position control and stiffness control separately.

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A poly vinyl chloride (PVC) gel actuator shows great potential for use as an artificial muscle because of such positive characteristics as movement in the air, large deformation, and being lightweight. We have proposed the structure of a contraction type actuator to construct an artificial muscle [4]-[6]. However, this actuator could not perform contraction force. In this study, we propose the structure of the multilayer PVC gel actuator to generate contraction force and evaluate its characteristics. The experimental results showed that the contraction rate of the proposed actuator was about 4%, and the contraction force was 1.9kPa. The characteristics of the PVC gel actuator are very effective for constructing an artificial muscle.

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It is necessary to estimate required joint torque for power-assist with an exoskeleton robot. In order to estimate required torque in control, relationship between the generated knee joint torque and EMG signals during the deep knee flexion is analyzed in this research.

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This study focuses on the importance of a riding posture of bicycle. Recently, the utilization of bicycle has been reviewed against latter social issues, such as global warming, destabilizing oil price, and diseases associated with adult lifestyle habits. A riding form of bicycle is basically determined with the mechanical settings of bicycle components, especially the saddle height has an significant influence on user's performance because muscular activities and joint mobilities are forcibly restricted. Conventional determination method for saddle height of bicycle is depending on the individual riding feelings, since there were no numerical evaluation method for the relationship between bicycle position and user's physical properties. Then we firstly define a new performance evaluation criterion based on leg electromyography during pedaling, and propose an optimization method of bicycle saddle height by using Fuzzy inference.

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Somatic sensation deteriorates due to aging and spinal cord injury. Training for the recovery of somatic sensation is required because of the prevention of overturning and the gait training. In this paper we propose a rehabilitation system to promote recovery of somatic sensation for patients with sensory disturbance caused by spinal cord injury. The prototype system consisting of a training device and two kinds of training applications for clinical experiments are developed. The training device consisting of electromagnets and a mouse (computing) enables us to give resistance feeling to patients.

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In this paper, we report light-weight robot namely Robot Skin which is guiding the upper-body motion for therapeutic application. This robot is designed by wear-comfort centric concept. To achieve this target we performed hand pulling test based on anatomical knowledge and we introduced actuator based on shape memory alloy for light weight actuator. To verify the advantage of the proposed method and the developed robot we carry out several experiments with healthy subjects to instruct upper limb and hand finger movement.

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Insects in nature can be regard as tiny and precision system. So in recent years, there are researches of cyborg insect, which utilize insects as micro-robot. However, there is issue battery cells that are too heavy and don't fit insect. In this paper, we propose to get electric power from insects. Power generation was done using two methods, transforming from insect motion energy and from an insect chemical energy into electric energy. Piezoelectric elements are used to transform insect's motion energy into electric energy. To transform insect chemical energy into electric energy, electrodes attached enzyme and mediator are implanted into insect body. As a result, output maximum electric power was 40nW from insect motion, and 581nW from insect body fluid. This result shows ability of a novel battery for cyborg insects.

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One of the control methods of leg mechanism imitating the motion control characteristics of human musculoskeletal system is proposed in this paper. In particular, the relation between muscular stiffness and/or stiffness of leg mechanism is considered. A servo motor is used for muscle. The muscular strength/stiffness is generated by performing apparent compliance control by giving servo rigidity using general position control. The arrangement of servo motors in the leg mechanism is equivalent to the human muscular arrangement with mono-articular muscles and bi-articular muscles. It is effective as the mechanism and control method for human mimetic flexible motion control.

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We developed a distant voice recognition system using a sound gathering parabola attached to an arm rest portion of a wheelchair as the control method of an electric wheelchair of having taken universal design into consideration. Because, a headset type microphone is kept at arm's length by elderly people and the woman. The run experiment under an environmental noise using this equipment was conducted. From the results, we verified the usefulness of using the parabola when the wheelchair was run under 60 [dB(A)] sound level. That sound level is same situation with a hospital room. We also verified the usefulness of the headset type microphone when recognized under over 60 [dB(A)] sound level.

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Since about 90% of the vision impaired in Japan are said to have low visual capacity (hereafter referred to as "LVs"), Tactile Walking Surface Indicator's("TWSIs") visual recognizability has great significance. For color conspicuity, sufficient data on LVs is not yet collected, while the data on people with on vision impairment are ready. In order to study proper TWSI colors, based on scientific-evidence and independent from conventional wisdom, we created a system to measure the conspicuity focusing exclusively on colors. In conclusion the system's usability to measure color conspicuity for LVs was verified.

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This paper provides a simple health care system based on vocalization. Our health care system is composed of a tonometer, a clinical thermometer, a microphone and a PC. This system can record several vital signs (blood pressure, pulse rate and bodily temperature) and voice simultaneously. We examine the relationship between the formants of vocalization and vital signs using the multiple regression analysis. The systolic pressure, diastolic pressure and bodily temperature are estimated based on the formants of vocalization.

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We propose a procedure to construct the environment burying IC tags for indoor navigation system. It is necessary for the environmental construction to put IC tags to constant distance and to write in information. Therefore, constructors spend much labor. We solve the problem by an automatic writing robot with omni-directional wheels and a PSoC. We checked the workings of the robot by easy experiments.

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This paper proposes a robust and practical positioning method of an underwater vehicle around support legs of on-water platforms. As our economic activity expands, some large-scale infrastructures such as runways and piers have been built as on-water platforms. Since such facilities are basis of national strength, it is very important to maintain their reliability through periodical inspection and patrol. The method enables an underwater vehicle, especially an autonomous underwater vehicle (AUV) to operate around such structures in order to realize efficient and reliable maintenance of them. The key idea of the method is to stochastically update the vehicle's state relative to the support legs using two types of perceptional sensors, sonar and camera. This paper also reports the results of tank experiments using the AUV Tri-Dog 1.

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This paper introduces the underwater robot HAL-urabo. HAL-urabo is a hovering type autonomous underwater vehicle (AUV) designed to take part in student competitions, and to develop a functional lowcost AUV kit, with fully documented physical and electrical design and an open source code. The vehicle has an overall length of 0.83m and weighs 11kg, with a maximum depth rating of 10m. The basic concept behind the development of the vehicle is that a person without expert knowledge of ocean engineering could purchase the necessary components, and build an AUV for a budget of around 300,000yen, or US$3,000.

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Real-time accurate localization is essential for in many underwater vehicle applications. In particular, close-range seafloor observation requires precise positioning in relation to bottom structures or to coordinates on a map. This paper proposes a real-time terrain based localization method that realizes robust positioning that does not require any artificial landmarks. The method stochastically determines vehicle's position relative to the map using the Particle Filter method, based on an inertial navigation system (INS) and a profiling sonar mounted on the vehicle. The reference bathymetric map is constructed a prior, either by the vehicle itself, or by other platforms. The proposed method is implemented on the hovering type AUV TUNA-SAND and sea trials were carried out. We succeeded in the real-time localization and verified the performance of the proposed method.

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