As the number of automobiles in the world is increasing, problems associated with environment and safety are becoming serious matter. One of the solutions to these problems is platooning of trucks. Platooning means a number of vehicles form convoy and run in one group. One of the agendas for practical realization of this platooning is a self-tuning of control gains. In this paper, as a measure of self-tuning of control gains, fuzzy inference based self-tuning of control gains is proposed. This method makes a fuzzy inference from a meander cycle and amplitude of a vehicle, and outputs the changing rates of control gains. New gains are produced from the product of these output values and previous gains

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Nagasaki Prefectural Government is now promoting "Nagasaki EV&ITS Project" in Goto islands, Nagasaki. Its objectives are construction of a model of "Driving Tours of the Future" which integrates EV (Electric Vehicles) and ITS (Intelligent Transport Systems) and installation of EV, quick charging environment and information environment using ITS spots. Furthermore, construction of distributive micro grids is planned to realize an advanced EV society model where EV, ITS and smart grids are harmonizing each other. In this paper, this challenging project is introduced and it is proposed to utilize this environment as an experimental field for advanced technologies to build a next-generation society.

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Precise and accurate 3D model of a road structure is basic information that can be utilized for various purposes, such as safety measures, driving simulation, and reference data for autonomous driving. Generally, the 3D model of a tunnel has been constructed using gyro sensor, however, error accumulation becomes a considerable problem in the case of long tunnels. We tried a method to obtain the most optimal structure of a tunnel by geometric processing: (1) Acquire a set of partial structures by static scanning, and align them by 3D matching using edge feature (2) Fix the absolute position of the data at both ends of the tunnel by GPS and align the rest data again. We modeled the Kanaya Tunnel in Shin-Tomei Expressway, whose length is 4.6 km by this method. The error in lateral direction was up to 0.1% relative to the tunnel length.

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This paper proposes a novel force sensing device for laparoscopic instruments using air flow rate, which has the advantages of MRI-compatibility, easy fabrication/sterilization and compactness, compared to conventional devices. The proposed force sensor works with air flows through pipelines to its sensing part. Forces acting on the sensing part can be sensed by measuring the air flow rates because the impedance of the air flow channels varies depending on the applied forces. Based on this principle, a prototype of 3-axis force sensor embedded in a laparoscopic forceps was developed. Effectiveness and feasibility of the measurement principle was verified through a primary experiment using the prototype.

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This paper proposes a remotely operated brachytherapy system for oral cancer. The purpose of the system is to reduce exposure dose of the operator (healthcare workers) by keeping him or her away from Au grain-seeds at a distance of I m. The system is designed so that the operator can perform the same procedure as the conventional brachytherapy treatment. It is composed of a five degree-of-freedom applicator manipulator to implant Au grain-seeds, a finger device to grasp organs in mouth, operational parts for them, and a base arm. The applicator manipulator and the finger device are installed on the base arm fixed on a shield for radiation proof. The finger device is composed of a three-DoF parallel mechanism so that its fingertip can move in three directions. This paper shows results of insertion experiments.

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Laparoscopic surgery is an effective method as alternative to open surgery. Robotic manipulators with multi-DOF forceps have been reported. To ensure more intuitive and much safer manipulation, haptic sensation to operators is an indispensable function of the system. The high backdrivability of the pneumatic actuator allows the detection of external forces from pressure data and compliance control of the system without the use of force sensors. We have prototyped a model of surgical robot system, which has high performance in the estimation of external forces. In this paper, we developed a forceps manipulator with pneumatic drive having a rotating mechanism at the tip. The forceps has total 4-DOF including gripper. The redundant movement can be achieved with the 4-DOF supporting manipulator we have developed. Therefore, the forceps can improve the operability and external force estimation since the singular point can be avoided.

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In laparoscopic surgery, it is difficult to grasp organs such as liver, spleen and kidney using only slender laparoscopic surgery instruments. In this paper, we propose a three-fingered hand that can be inserted through a 10 mm trocar. Each finger is composed of two springs which are cut from cylindrical columns and driven by pneumatic cylinders to bend in order to achieve a soft grasp of organs. In addition to that, this mechanism helps us to estimate a grasping force for organs. Therefore, this hand is adequate for grasping organs. The mechanism of the hand is introduced. Then, the effectiveness of this hand is demonstrated with some experiments.

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This paper describes a trajectory generation method for a master-slave surgical robotic system. Because the data from the master system is intermittent due to the limit in master-slave communication rate, interpolation is required to achieve the smooth motion of the slave robot. In particular, real-time interpolation is crucial for surgical systems. To cope with this problem, we propose a new smooth trajectory generation method by minimizing jerk using a quintic B-spline. To ensure the third-order continuity in position, velocity and acceleration, the trajectory of next time segment is generated using several fictive control points. In addition, we impose a minimum jerk constraint to obtain a smooth trajectory. The proposed method was tested and compared with a conventional trajectory generation method. The experimental results show that the proposed method generated a smoother trajectory with fewer jerks, which is sufficient for use in real-time control of the surgical robotic system.

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Furusho Laboratory of Fukui University of Technology is developing PLEMO series which are passive type rehabilitation system only using brakes. In this study, we developed new type brake using nanoparticle MR fluid and conducted conceptual design of rehabilitation system.

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Furusho Laboratory of Fukui University of Technology is developing PLEMO series which are passive type rehabilitation system only using brakes. In this study, we developed rehabilitation software using Flash/AS3 for graphics and C language for control software.

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The Profhand is a cycling chair that is used for mobility and rehabilitation of the disabled. This study aims to improve the performance of the Profhand in outdoor environments. The Profhand has problems with climbing over steps and slopes which are commonly found in roadways and sidewalks. To solve this problem, this research intends to implement a power assist system for the Profhand. A power assist system also has the added benefit of increasing the distance the user can travel. In this paper, improvement of the structure for climbing over steps is presented.

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Crutches are often used in rehabilitation by injured patients. However, patients are not usually familiar with how to use crutches properly. Improper usage can cause the patients to fall, potentially leading to further injury. In order to ensure patients' safety, a training environment for crutch walk training with a LCD projector was developed. In this training environment, proper landing position was estimated from the motion of a crutch, and it was instructed on the walk way by a LCD projector that is hung from the ceiling. The effectiveness of landing position instruction with a LCD projector was confirmed through experiment.

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The lower extremity dysfunction uses knee-ankle-foot orthosis (KAFO) that fix the movement of the knee to prevent giving way. However, because the movement of the knee is fixed, walking is difficult. So, they want the knee joint with extension stop that can fix knee to extension position during the stance phase, and flex knee during the swing phase. Therefore, we developed the stance-control (SC) system. This SC system presumes the lower limbs motion from the plantar pattern, and it controls the movement of the knee.

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This paper presents a micro computer based controller for joystick car drive systems. The controller controls a motor angle so that a angle of steering wheel or that of gas/brake pedals are operated to drive and maneuver vehicles. The disconnection of wires and devices can be detected by the controller, such as a motor, potentio-meters, and a clutch. To measure dynamic parameter changes or to manage control parameters, support software for PC are also developed together with the controller.

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Recently, laparoscopic surgery has been performed in abdominal surgery, and a variety of robotic support systems for laparoscopic surgery have been developed. We have developed a multi-DOF robotic forceps manipulator using a novel omnidirectional bending mechanism termed double-screw-drive (DSD) mechanism, so far. However, the tip of this manipulator can move only on the hemisphere surface. In this paper, the DSD mechanism was improved so as to extend a motion space of the tip position, which is termed new DSD mechanism. Kinematics of the new DSD mechanism was analyzed, and equations to control the new DSD mechanism into the given bending posture were derived. In addition, experiment on position tracking control was carried out using a joystick-type manipulator for teleoperation.

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This paper presents the development of a small size multi-degree-of-freedom manipulator for medical applications using high precision 3D cam mechanism and crown gear reducer. The 3D cam functions similar to a bevel gear in that it is a transmission mechanism for nonparallel input-output axes. However, the 3D cam mechanism has theoretically zero backlash can be miniaturized much easier than a bevel gear. Using the 3D cam mechanism, the multi-degree-of-freedom manipulator was implemented as a serial manipulator. Results of the evaluation of the prototype small size multi-degree-of-freedom manipulator are presented.

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Surgery simulator is expected to help plan surgery procedures and train surgical techniques. In brain surgery, blunt dissection simulation is needed because it is a basic and important technique. Nakayama et al. proposed a method of computing fracture of soft tissue for blunt dissection simulation. However real-time simulation had not been achieved because of its high computational cost. This paper shows the system of the blunt dissection simulator with a haptic interface, and proposes a method for construction of real brain Finite Element Method(FEM) model by scanning the surface of a pig brain using a laser displacement sensor. Additionally the real-time performance of the simulator which parallelized by a multi-core processor is evaluated.

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In this paper, development and evaluation of a haptic device for a brain surgery simulator are presented. The haptic device enables to simulate medical operations with both hands at the area near the tip of two surgical instruments. In this study, a module for micro scissors was developed and evaluated by force display experiment. Furthermore, force display performance of the haptic device was evaluated by push simulation using a cube model of brain tissue. The results clarify the issues of the module and the haptic device.

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Autonomous positioning of surgical robotic forceps is very promising toward high-level assistant function such as automated task. It is the first step toward autonomous surgical systems that can make full use of the robotic system. To achieve high accuracy in positioning, visual servoing technique is utilized in many applications. However, in visual servoing, we cannot control the trajectory of motion in Cartesian space. Undesired behavior of forceps in Cartesian space may make damage to tissue or blood vessels. To cope with the problem, we propose a vision-guided positioning system with z-separated visual servoing. The interaction matrix is decomposed into positioning and approaching components. Approaching velocity is computed on the basis of difference of disparity, and positioning velocity is yielded by reformulated interaction matrix. The experimental results showed that the proposed method can control the trajectory in Cartesian space by adjusting approaching parameter. Furthermore, the needle gripping task is successfully performed. We expect that this method would be used for autonomous surgical system.

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The EMG information is mainly used for the interface of powered prostheses. However, it is difficult to bend fingers to a specified angle like a human. In this paper, five fingers are selected from ten fingers of feet for operating powered prosthesis's fingers. This system is to operate each finger of powered prostheses by obtaining joint displacement information of the fingers of feet. The joint displacement information is obtained with the five bend sensors. This proposed method makes it possible to operate each finger of powered prostheses independently.

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In this research, the person who requires long-term care is focused on. It's very hard for them to control complicated care support robots. Thus, we propose Multi Modal User Interface using 3 modes; "Motion and Gesture", "Shape of mouth" and "Gaze". This interface provides comfortable robot operation according to the care-receiver's physical disability. In this thesis, especially, "Motion and Gesture" is focused on.

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An Omni-direction type cane is designed for aiding the elderly and handicapped people walking. Fall prevention algorithm based on the relationship between user's COG and the cane is proposed. Because the size of the cane robot is small, when the robot is preventing the user falling down, the stability of the cane robot should be ensured firstly. Therefore, a new mechanical part called universal joint is designed for improving the stability of cane robot whiles the cane robot preventing the user falling down. The universal joint which is driven by two DC motors can reduce the moment that causing it falling over.

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Personal computers have much information of characters or figure. Therefore, it is difficult for visually impaired persons or elderly people to use PC relying on visual sensation. In response to this problem, various human interface were developed to support PC operation. However, these are not widely used yet. In this study, we aim to develop a force display touchpad for supporting PC use. This device presents information on the screen using the force. The 1st report described its basic concept and prototype. In this report, we have added a function on this device, which is similar to the ordinary tap function of touchpad.

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The purpose of this research is to develop a chopsticks type self-help device which allows the person with handicapped finger to have meal as healthy person do. The device is manipulated based on residual function of the subjects. Experimental results have shown that the device allow the person with handicapped finger to eat bite-size food and noodle. In this paper, in order to discuss about the effectiveness and improvements, we compare the eating motion by using the device with the motion by using the chopsticks. We analyze the comparison results focused on the taken time for meal and displacement of hand or head. Based on the analysis , we consider the improvement points of the device.

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The goal of this study is to develop a robot prosthetic hand system for amputees that estimate his/her desired finger angle from biosignals such as electromyography (EMG) signals or nerve signals and operate with the same motion as user's intention. Thus we have already proposed a finger joint angle estimation method using a histogram of surface EMG signals and a linear model. However, this method has a problem that the estimated angle is oscillated when a subject keeps his/her finger flexion. To solve this problem, we propose a new method to avoid estimator oscillation using time variation of histogram of flexor muscle. Moreover, a 2-DOF artificial finger robot has been designed and developed for patients who have his/her finger cut off. Using this robot and applying our proposed finger joint angle estimation method, we carried out the experiments that synchronize the robot with the subject's 3rd finger motion.

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In this paper, a force feedback control system for robotic surgery is constructed by using the force reflection type bilateral control. The haptic device 'Omega.7' is used as a master device, and two kinds of robotic forceps are used as a slave device. The DSD forceps is employed as the slave device for bending motion, and the modified RoticulatorTM forceps is employed as the slave device for grasping motion of the jaw. The motion of the robotic forceps tracks a manipulation of the 'Omega.7', and force added to the robotic forceps is reproduced on the 'Omega.7' as the reaction force. Therefore, operator can feel the reaction force in teleoperation. Experimental works were executed to verify the tracking performance of both position and force for the constructed force feedback control system.

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In this paper, we explain the surgical arm. First, we improve a conventional free brain spatula fixed instrument to advance its operability. The medical instrument has a flexible mechanism consisting of series of cylinders and sphere. Second, we propose a new type of surgical arm with multiple passive joints that can hold medical instruments or incised part etc. The proposed arm consists of differential gears, crossed helical gears and universal drive joints.

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Minimally Invasive Surgeries (MIS) becomes popular by use of catheters and forceps. The forceps generally consists of many micro parts, that makes it difficult to assemble the forceps. Therefore, we have developed a one part grasping forceps. The new forceps is no assemblage and no risk of part decomposition. This paper presents designing of grasping forceps, analysis of structure and verification experiment. As a result, the forceps grasped successfully platinum coil. The new forceps may innovate a new way of MIS.

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In this research, for supporting the disabled, we propose Multi Modal User Interface using 3 modes; "Motion and Gesture", "Shape of mouth" and "Gaze". This interface provides comfortable robot operation according to the care-receiver's physical disability. In this paper, "Gaze" mode is mainly explained and the experimental results are shown.

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This paper describes improvement of response capability to escalator of variably configured wheelchair with Z shape link mechanism. Escalator is an effective mass transportation method. But original wheelchair can't use escalator because of its instability on the uneven height steps. Accordingly in order to make the wheelchair correspond to escalator, Z shape link mechanism is applied to original wheelchair. In addition, mount mechanism to deform Z shape link. The method of experiment, measures the load of front wheels when height of escalator's step is given. Then research distance from rear wheels axle to the center of gravity on the load of front wheels. The experimental result shows that the stability on the escalator can be kept. Thereby, the response capability to escalator improved.

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The level walking of the passive walker that is realized only by a waist assist is high transfer efficiency very much. However, it is necessary to be beyond a potential barrier easily for the autonomy level walking. And, how to walk walking robot is very similar to a person's. Before, we studied the walking assist device based on human-assisted passive walking. In this paper, we introduce walking assist device harmonized with human and demonstrate an effect that the walking assist device gives to human walking.

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An active orthosis, called powered glove, is under development to provide pinching function to cervical cord injury patients. The ortotic part of this powered glove system is a leather glove that has drive strings which work like human tendons to flex/extend fingers. The tension of drive strings is controlled by a controller based on user's command. The command signal is obtained by a belt shaped interface fixed on user's head. This interface detects activity of temporal muscle which works to close a jaw. Therefore the user can operate the powered glove through gentle chewing. A prototyped glove system is applied to two cervical cord injury patients and tested how well the powered glove can improve upper limb ability of cervical cord injury patients by providing pinching function. It is observed that the prototyped glove system extends upper limb ability of both patients through the evaluation test.

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