A novel Kalman filter for dead reckoning of biped robots is proposed. In order to reflect the change of the foot contact condition, its observation error model is adaptively varied in accordance with the reaction force. For the rolling or rotation happened on the supporting foot, the minimum velocity point (MVP) which proposed in our previous work is introduced into the kinematics computation. MVP estimation is sensitive to the attitude error, so that we lower that influence by taking the ground reaction force at the contact point into consideration. The efficacy of the proposed method is verified through simulations.

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The proposed robot recommendation system is able to make recommendations based on the real-time estimation of the shopper's choice. Our system estimates shoppers' attentions using only head movements The first experiment validated the capability of our intention estimator in a kiosk-shop scenario. In the second experiment, a Humanoid robot intervened in the decision process. As a result, we found that our system significantly changed the shoppers' choices in the two-alternative-forced-choice literature.

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In this paper, we developed a new human-like robotic upper limb with large working area thanks to the novel robotic shoulder using a double joint mechanism. This joint mechanism is composed of two ball joints driven by the pneumatically connected linear actuator pairs to enlarge the range of motion compared to a simple ball joint while keeping the simplicity of the control. Thanks to not only the robotic shoulder but also the robotic blade bone and elbow joint with human comparable range of motion, the robot is capable of throwing a ball like a human. We also investigated the characteristics of the shoulder joint mechanism.

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Ultrasound-guided needle placement such as radiofrequency ablation has been widely used for safe and low-invasive procedures. Meanwhile, an ultrasound probe has to be placed for monitoring tumor and needle positions. Therefore, we have developed a probe scanning robot using pneumatic actuators to automatically visualize a needle in 2D echogram plane. However, it was difficult that the system with a conventional 2D probe follows both the target tumor and the needle. Thus, focusing on xPlane imaging of a matrix array probe, which provides two cross-sectional echograms in real-time, we developed an improved system to compensate three-dimensional motion of a target by the visual feedback.

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Laparoscopic surgery brings many benefits for patients such as smaller scars, less pain, and shorter hospitalization compared with open surgery. Moreover recently, single-incision laparoscopic surgery (SILS), in which surgical instruments and a laparoscope are inserted into a single incision, provides more cosmetic benefits than the conventional laparoscopic surgery and has received a lot of attention as "scarless surgery" although it is more difficult to operate it than laparoscopic surgery. In order to overcome the difficulty of SILS, we developed a locally-operated master device and a flexible slave robot system, and confirmed the feasibility of the proposed system by conducting a basic task and an ex vivo cholecystectomy using a box trainer. As results of the experiments, we confirmed that our system provided surgeons shorter switching time, more stable operation, and fewer collisions than the conventional SILS. We also showed that the proposed system is available for single-port laparoscopic cholecystectomy.

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This paper presents a simple training simulator for endoscopic surgery based on augmented reality. The basic function of our proposal is to provide repetitive practice the fundamental operations for cutting, removing, and suturing organ tissue. Augmented reality indicates a straight line and/or a circulate line on a display as a target trajectory for training. After constructing the basic functions of the training simulator, we will evaluate the training effects with beginner students.

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In the purpose of pathological state by exhalation, we have developed an expiration gas analysis system. Also now there are various problems when subjects use the equipment for collecting breath gas. So we have developed the new equipment for collecting breath gas that using a pressure sensor to improve the ability to collect the sample. And because we want to know the difference between breathing resistance of the new equipment for collecting breath gas and currently equipment for collecting breath gas. So we have a subject to use the equipment of both. And we examined the breathing resistance at that time.

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This paper addresses falling prevention by a humanoid robot which adaptively switches a standing balance controller and a hopping motion controller. In the previous research, the author proposed a switching framework between a balance controller and stepping motion controller based on the Maximal Output Admissible (MOA) set. Different from stepping or walking motion, a hopping motion requires control of COG in the vertical direction. In this paper, the MOA set is extended so as to deal with the vertical COG dynamics. The effectiveness is validated with a simulation of falling prevention.

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Motion control of a humanoid robot is challenging problem because its dynamics is complicated. In previous studies, a macroscopic model is derived from the relationship between the Center of Gravity (COG) and Zero Moment Point (ZMP) to make it easier to design controllers. The authors proposed the maximal output admissible (MOA) set framework based on the macroscopic model and applied it to the falling avoidance control. In this paper, we approximately calculate the MOA set on a humanoid robot with joint servo system by measurement and identification of a response to a disturbance. The effectiveness of the proposed method is verified with an experiment.

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This paper describes the development of a one-legged jumping robot with artificial muscles. The jumping robot has a waist, a knee and an ankle. Its weight is 12.34 kg, and its height is 1010 mm. The jumping robot has a total of 13 actuators: 10 mono-articular types and 3 bi-articular types. A pneumatic artificial muscle actuator that can expand radially and contract axially is used. The actuators for mono-articular and bi-articular muscles are installed in the rear and the front of the thigh and the shin for the muscles to antagonize each other. The effectiveness of the mechanism of the jumping robot is verified through a jumping experiment.

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This research shows how to apply the Reaction Null-Space method for controller design of a humanoid robot such that the balance and motion/force control subtasks are dynamically decoupled. The performance of the controller is verified via simulations, using the model of a miniature humanoid robot HOAP-2.

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This paper presents Support System for auto-Pathological Diagnosis (P-SSD) to make the supervised database. In Japan, cancer is the most cause of death, and the number of patients who are suffering with cancer is still increasing. However pathologists are almost constant. This makes them lot busy, and tends to cause the fault of the diagnosis. To prevent the fault of the diagnosis, auto pathological diagnosis is needed. A lot of methods for auto pathological diagnosis have been proposed, however, pathological images are usually unique format, and researchers need to have special knowledge to work on these images. Therefore we proposed P-SSD to support for researchers and pathologists. P-SSD enables us to handle unique format with OpenCV. In addition, P-SSD have the other functions to make developing auto pathological diagnosis easily. P-SSD consists of the four functions. In this paper, we developed the system which makes the supervised database.

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We have studied technologizing and digitalizing methodologies for medical professional skills based on the mechanism, control, and image processing technologies. In this paper, we analyzed the probe manipulation task between rib bones and propose probe manipulation mechanisms to acquire ultrasound images avoiding the effects of rib bones.

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Minimally invasive surgery accelerates postoperative recovery, but can only be applied by surgeons having advanced surgical skills. This paper introduces a master-slave manipulator system for laparoscopic surgery using a 6-axis vertical articulated robot for a slave arm with a forceps. The control mode of the system consists of a non-trocar mode, a trocar mode and a transitional mode between the two modes in order to ensure insert and remove motions of the forceps. An orientation adjustment motion before an insert motion of the forceps under the transitional mode is achieved by the motion of the 4th axis and the 5th axis of the slave arm. The orientation adjustment motion and insert motion under the transitional mode and master-slave motion under the trocar mode are shown by evaluation experiments of the master-slave manipulator system including the 6-axis vertical articulated robot.

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In the needle insertion procedure, the physician detects to reach the insertion target using the force acting on the needle tip. So, the friction force should be compensated. The research of estimating the friction force in real time has not performed. In this study, we designed the estimation system of the friction force using the characteristic of the needle insertion force. As the result of needle insertion experiment, we elucidated a characteristic that the slope of the total insertion force and friction force regression line was 1.0 during the needle insertion. The friction force acting on the needle was modeled based on the characteristic that is result of needle insertion experiment. The estimated and measured friction forces were found to be qualitatively consistent.

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We develop and study a manual stop switch of the mobile robot. We evaluate manual stop system by questionnaire. The operator or administrator is not near to the mobile robot at all times, so it is necessary to find uncontrollable robot and stop it by third person. In addition, the range of movement of the robot is wide and there are some situations which are dangerous. We are trying to solve this problem using a prototype switch using a mesh network. We develop safety switch and send out questionnaire in my laboratory to evaluate practicability of it. As a result, we show efficiency and safety through use of whole system.

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Japan is rapidly aging. It is expected that elderly patients who need gait training will increase. We have developed a passive-type walking support machine equipped with a lift device which provides a patient with partial body weight support and prevents the patient from falling down. In this paper, we propose a new walking support system which consists of the lift device and a treadmill. The treadmill has a safety device. The safety device is controlled by a motor and prevents the patient from falling down, when the controller of the walking support system works. Furthermore, the safety device can stop the belt of the treadmill if the safety device detects an unexpected velocity of the belt under breaking down of the controller. The effectiveness of the treadmill with the safety device is verified by experiments.

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In Japan, the number of aged people is rapidly increasing. It is expected that elderly patients who need gait training will increase. In hospitals, walking support robots are needed that can safely support the gait training. We have proposed a walking support robot equipped with two velocity-based safety devices and experimentally examined the usefulness of the velocity-based safety devices. This paper proposes a new walking support robot equipped with not only two velocity-based safety devices but also a contact force-based safety device. These safety devices consist of only mechanical components without actuators, controllers, or batteries. Firstly, we explain the walking support robot proposed in this paper. Secondly, we show the developed walking support robot. Finally, we verify the effectiveness of the contact force-based safety device by experiments.

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Human safety is one of the most important issues in human-friendly robotics. We have proposed a safety device to improve the safety of human-friendly robots for humans. The safety device consists of only mechanical components without actuators, controllers and batteries. The safety device is attached to each drive-shaft of a robot and locks the drive-shaft after detecting an unexpected robot motion on the basis of the drive-shaft's angular velocity. In this paper, we start with reviewing the structure and mechanism of the safety device. Then, we explain a theoretical analysis of the safety device. Furthermore, we propose a method for further improving the safety device. Finally, we discuss the effectiveness of the method for improving the safety device from the theoretical analysis results and the experimental results.

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This paper describes a patient robot in psychiatric field as an application of android robots which have human-like appearance. The purpose of the patient robot is to offer reproducible and realistic interview training to psychiatric trainees as a standardized patient of unipolar depression. Subjective evaluation of educational and training effects of interview training with the patient robot was evaluated in actual psychiatric education by the experiment in which students conducted an interview with the patient robot.

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A five degree-of-freedom miniature parallel robot has been developed to precisely and safely remove the thin internal limiting membrane in the eye ground during the eye surgery called vitreoretinal surgery. A simulator has also been developed to determine the design parameters of the robot. The size of the developed robot is 85 mm x 100 mm x 240 mm, and the weight is 770 g. The robot incorporates a function for emergency retraction to remove the surgical instrument from the eye in case of bleeding. Experiments were conducted to evaluate the performance, and the results demonstrated that the robot satisfied all the requirements and had the positioning resolution of 12.7 μm.

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Purpose of this study was development of the new devices that could manipulate a hydrogel as a support for the cell sheet with air pressure. With reference to the stamp-type device to be used for the cell sheet stacking, the convex-type device for limiting the contact area with the support of the cell sheet was developed. The device was evaluated by measuring suction force to hold the hydrogel and by transport experiment considering clinical usage. It was confirmed that the developed device had enough suction force to hold the hydrogel. The hydrogel using the convex-type device failed to transport in the case of vacuum break. The reason why vacuum break occurred was that surface of the device could not follow the deformation of the hydrogel due to hardness of the device.

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Recently, movable-tip laparoscopes have been developed and commercially used. Many kinds of laparoscope holder control systems also have been developed and commercially available. Conventional laparoscope holders, however, cannot drive a tip joint of a movable-tip laparoscope. In this paper, we develop a laparoscope holder control system where a movable-tip laparoscope is held by the 4-DOF pneumatic-driven scope holder we developed, and the tip joint of the laparoscope is driven by a link mechanism using pneumatic cylinders. PD and PID control and feed forward control based on inverse dynamics of the scope holder and the device driving the tip joint are applied to the system.The experiment of the laparoscope position control shows that the laparoscope can be controlled to watch an object in different viewpoints in this system.

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There is a social demand on a wearable robot that is useful in enhancing wearer's locomotive capabilities.However,a wearable robot has some unique risks.Fall is one of the most severe risk.This study focuses on the effect of applying sudden motion interference to the wearer when using a wearable robot.A motion capture system and forceplates record the human response to the perturbation to assess a risk of fall.We observe a characterized response like circumduction gait and effectiveness of the recovery despite the change in the joint angles and COPs.

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In order to develop a safe robot, it must be protected from a harm by a robot. Determining the specifications of the robot to identify hazards, we must conduct a risk assessment based on the specifications. In this report, a case study of developing a vending robot, we performed a determination of the specifications and a risk assessment. As a result, we can analyze that much of the harm is the crash between human and robot. We proposed safety measures to reduce this risk and investigated the crash safety testing and running durability test in order to verify measures of the effect.

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In this study, it aim to develop the system to operate the robots safely and efficiently. Especially, I research avoidance behavior of mobile robots to prevent mobile robots from crashing. This behavior based on attribute of the obstacle (ex. Speed of obstacle, probability of movement, personal space).This study, it is expected that such home, or office, to accelerate the dissemination of mobile robots coexisting with human.

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As the complexity of robots deployed in the real world increases, the use of formal specifications in the development of safety-critical robot systems is becoming increasingly important. A formal specification gives confidence in the correctness, completeness, and accuracy of a system design. In this paper, we present a model of a redundant control architecture for a mobile robot. The model is specified using the Architecture Analysis and Design Language (AADL). This formal language allows the model to be analysed to prove system properties such as sufficient processor capacity and control latency. We present the results of a model completeness analysis, a processor capacity analysis, and a latency analysis.

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In this paper, we achieved the local micro-injection into C. elegans with multiple microbeads. The multiple probe type injection tool was developed to inject multiple microbeads into C. elegans at one time. We tried to inject as line or spot area of C. elegans body.

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We developed a valve fractal stent to treat the cerebral aneurysm what is one of a cerebrovascular disease. The stent has a valve part to path through a coil. The valves have fractal structures. So, the blood flowing into cerebral aneurysm is prevented. We performed a Particle Image Velocimetry (PIV) experiment to evaluate the inflow into cerebral aneurysm. By the experiment result, we visualized the stream line by using the cerebral aneurysm. By calculation, we succeeded in a 55% reduction in the inflow by using the valve fractal stent.

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For analysis of biological samples, e.g. flagellar motor, we previously proposed the local environmental control system with nano/micro dual pipettes to change local ion/reagent concentration arbitrarily. However, in this system, the capability to control the local ion/reagent concentration was not sufficient. So, in this paper, to achieve more arbitrary local environmental control, we propose on-chip local environmental control system using micro fluidic chip with world-to-chip interface (WtCI) and micropipette. We develop the system and demonstrate the feasibility of the on-chip local environmental control system using micro fluidic chip with WtCI and micropipette.

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The single cell analysis has attracted much attention to reveal the detailed and localized biological information, which is not obtained by the conventional group cell analysis due to the statistical assay, on individual cells. To analyze the detailed and localized properties of single cells, local environmental control technique, which is the technique to change and sense the local environment around single cells, is effective. Therefore, local environmental control technology for single cell analysis is desired and being established. In particular, a system that operates with stability is important. To build the system which can achieve high speed (high time resolution) and prolonged analysis is useful for an understanding of various life processes. For example, biological molecular motor is a good candidate for analysis. In this study, we try to develop a real time and long time observation system that can changing and keeping local environment condition stably. And then we apply this system for analyze the one kind of biological molecular motor, "bacteria flagella motor", which rotational principle is largely unknown.

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This paper describes the development of a waist of a human friendly robot. The waist that has 3DOFs installs a collision force suppression mechanism every joint. Also, the whole robot body is covered by air cushion bag. When a collision between an object and the robot occurs, collision force is suppressed passively by the collision force suppression mechanism and the air cushion. Using the robot, collision experiments are conducted and the effectiveness of the collision force suppression mechanism is confirmed.

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The goal of this research is to develop a fail-safe safety tactile sensor using a viscoelastic tube and an ultrasonic signal, which is flexible and detectable a wide area with high reliability. As a fundamental experiment, in this paper, the propagation characteristics of an ultrasonic signal in a bending viscoelastic tube are investigated. Through the experimental results, we could drive the estimation equations of the rate of sound pressure loss and propagation time delay due to a tube curvature, and found that there was strong correlation between the coefficient of the sound pressure loss rate and time delay. The effectiveness of the estimation method was confirmed through an experiment. In addition, self-diagnostic algorithm was also proposed to realize a self-diagnosis of the sensor system.

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In this paper, we focus on a safety system for human-manipulator cooperation works. The safety system is to avoid collision between the human and the manipulator for safe humanmanipulator cooperation work using a high speed perception system of the environment. First, new safety distance is defined because International Organization for Standardization (ISO) only lays down rules on the safety distance by sensor curtains. Our new safety distance shows that high sampling rate can improve safety for the cooperating works with human. Then, highspeed 3D measurement using volume intersection is introduced. Our system can reach 100 [Hz] sampling rate on 2.5 GHz Intel Core i5 PC. Finally, we explain collision avoidance algorithm. In the experiment, the manipulator was successfully able to avoid collision with the human.

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In this paper, we proposed a stiffness changeable joint mechanism with a fail-safe function. The mechanism can change its stiffness to three states, elastic-solid-elastic, according to the safety and task situation. Each stiffness state can be switched by positioning a stiffness changing part moved by a rotary slider that is automatically return to its original state. The prototype of the joint mechanism was manufactured and its stiffness changeable function was confirmed. In addition, its impact force reduction function was confirmed through impact experiments.

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In this paper, to improve the spatiotemporal resolution and to reduce the invasiveness, mouse muscle cell lines, C2C12 myoblasts were genetically introduced light-gated ion channel, channelrhodopsin (ChR). The light pulses depolarized the membrane potential of a ChR-expressing myotube and eventually evoked action potentials dependent on the intensity and duration of the illumination. The light-activated contraction of the photosensitive myotube was obvious in synchronous to the light pulses of the given frequency and the pattern (1-10 Hz). This technique could facilitate the studies such as the fundamental biological processes during myogenic development, the stem cell therapy for muscular disorder, and the bioengineering using the muscle-powered actuator.

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In this study, we measured mechanical properties of cell sheet by using uniaxial tensile test system which we developed. We applied kelvin model (viscoelastic model) which applied single cells for deriving mechanical properties such as elastic modulus and viscous modulus. Mechanical properties of Fibroblast (NIH-3T3) cell sheet and myoblast (C2C12) cell sheet were derived by fitting equation which related kelvin model to measured stress-strain curves of cell sheet. Furthermore, for confirming drag response on cell sheet mechanical properties. By deriving mechanical properties of cell sheet, we confirmed mechanical properties of cell sheet which are different from that of single cells.

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This manipulation method we proposed can implement the multi-freedom manipulation of bio-objects without contact in an open space. Compared with other bio-micro manipulation methods, this system manipulates a micro object by controlling multiple microfluidic streams onto it. The advantage of this method is open space, multi-function, multi-scale, and non-invasive manipulation.

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Reasonable risk estimation is indispensable for building a safe human-robot coexistence system. Risks are estimated from the severity of harm and the probability of occurrence of harm in which we focus on the latter. Taking into consideration the possibility of avoiding or limiting harm, we propose a new method for estimating the collision probability between an end-effector tip and an eyeball when the robot goes out of control. With a self-diagnosis function, the robot makes the braking motion and comes to a complete stop. The method basically computes the intersection between the two volumes of the manipulability ellipsoid constructed through motions of the end-effector tip and a human eye.

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A robot operator is required to work in close proximity to the industrial robot while power of robot actuators is active. Physical contact between the operator and the robot can occur during the operations, especially collaborative mode. In these operations, the robot requires power and force limitation which is provided as 80W of rated motor power by the japanese regulation. This report describes that the actual motor power around 80W is measured as an operating force toward the operator and the risk of measured force level is considered.

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Recent years, Japan is facing a "Super Aging Society". The various types of electric wheelchairs are developed and offered commercially for old people and/or disabled people. However, wheelchair-related accidents have increased in each year. In this research, we pay attention to the electric wheelchair driving support. We look at the functional safety of the electric wheelchair. Based on intrinsically-safe electric wheelchair, we add driving support system to increase functional safety. The driving support system processes the environmental information sensor data including the 3D laser Range scanner and biological monitoring sensor data including electrooculogram, and assists avoidance of dangerous objects.

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Atmosphere representation/understanding for humans-robots interaction in multi-agent society is investigated by applying the concept of atmosfield, support vector regression, and a new visualization method using fuzzy sets. It provides the necessary information for each agent to communicate with each other smoothly. Experiments by four agents (humans) are done using 13 scenarios that cover most part of the atmosfield, and it is confirmed that the necessary atmosphere information for each agent is obtained with the average accuracy 90%. It is aimed to open a new way for the realization of a human friendly distance education system as a potential application of the proposals.

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Next-generation lunar/planetary exploration spacecraft need to solve problems of conventional landing methods and mechanisms such as high rebound, impossibility of reuse and high cost. For this purpose, the authors discuss the landing method by means of Base-Extension Separation landing Mechanism (BESM) which uses energy conversion with springs and separable units. In the authors' conventional studies, its effectiveness was confirmed for a simple case based on single-axis restriction. However, the investigation of tumble prevention cannot be treated in the simple case. The purpose of this preliminary report is the response analysis of a slope landing case of BESM for more practical landing situations.

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We have developed a mechatronic-system-embedded building blocks, named 'mechatro-tsumiki' that interacts with player's operations such as assembling, building, stacking, lining-up, and handling. We develop the novel 'mechatro-tsumiki' prototypes utilizing the characteristics of various wooden materials. When various vooden materials are applied for the 'mechatro-tsumiki' blocks, each block has the distinctive character according to the wooden material applied. We applied six types of wooden materials for the 'mechatro-tsumiki' blocks in this study, then we evaluated their differences based on the characteristics of the wooden materials.

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We developed a practical legged robot system "Whitegoat Mk II" with a wide range and highly durable telescopic manipulator. This is a successor of our multi legged robot series based on our original 3D linkage leg driving mechanism. The points of redesign are: simplified structure for mass production; replacement of the original parts to commercially available parts stocks. Through the trial operations, the each modified units show the intended performances. This Whitegoat Mk II will be a reference of the production model.

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In this paper, we propose the methods to deform the robot hands made of shape memory gel efficiently. We have developed the robots using the shape memory gel and performed their basic experiments. The shape memory gel is rigid at room temperature and soft at high temperature. The robot using shape memory gel can be deformed repeatedly. We develop two kinds of the system. One is press machine system and the other is molding system using grasped objects. The former is the system to press and deform heated and soft robot hand using linear transmission and molds. The latter is the system to grasp intricately-shaped objects.

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Battery capacity is a bottleneck for long-term deployment of an AUV. Recently, the use of a seafloor station has been proposed for extended deployment of an AUV. This paper reports about a development of noncontact charging system by electromagnetic field resonant coupling for long-term development of a hovering type AUV. It was experimentally verified that the system can send about 200W of electricity through seawater at the gap of 15mm.

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In this study, we develop a curved surface adaptive unit to realize snake robots' undulatory progression on a curved surface such as cylindrical surface. The unit is composed of unit-compliance mechanism using springs between unit and robot, and wheels-stretching mechanism using slider link between wheels. The unit can adapt to changes in relative position of a curved surface and the robot, and changes in distance between surface contact point and the unit center. Experiment with snake robot on cylinder surface is carried out in order to demonstrate the effectiveness of the adaptive function to curved surface of the developed unit.

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The climbing robot for traveling outside pipe or trees, is required a special mechanism different from the moving mechanism for performing normal flat road. For example, snake-like robot with the articulated mechanism is raised and lowered while rotating the body by controlling the complexity of the joint, or the climbing tree robot that while holding the pillar body by gripping mechanism such as a robotic hand. Under such circumstances, we aimed at implementation of a climbing plant like robot which can climb pipes and trees by winding its body. In this study, we developed winding mechanism inspired by climbing plant. It consists of silicone rubber, reinforced fiber and air hose. It can wind for pipes by using air pressure. In this paper, we report a basic design and prototype evaluation of the winding mechanism driven by air pressure.

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The conventional screw propeller is widely used to propel boats and underwater vehicles. Recently, the use of a bio-inspired oscillating elastic fin has been proposed as an alternative propulsion mechanism. It is thought that the new mechanism will improve efficiency and safety, relative to the screw propeller. The optimum elasticity of the fin is not constant and changes based on swimming speed and task. However, it is very difficult to exchange fins of different stiffness while moving. We have developed a propulsion mechanism using a variable stiffness fin with torsional rectangular elastic plates. In this study, we made a model boat to provide basic data for the development of the boats and autonomous underwater vehicles using the variable stiffness fin. In this paper, we examined the propulsion characteristics of the model boat using two different shapes of the fins: previous rectangle fin and crescent shaped fin.

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