In this paper, we propose an eye robot system with master slave control using operator-gaze tracking data, which can produce a high response level such as that of the human eyes. The operators can move a remote robot camera by only moving their eye (master) in front of an eye tracking apparatus and obtain visual information of the environment surrounding the robot's eye (slave). The use of ultrasonic motors has enabled the high responsiveness of the robot eye and the compactness of the robot body. In addition, we propose a graphical user interface (GUI) that makes the robot operation intuitive.

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This paper proposes reduction device by using fluid film lubrication type wave generator for robot and mechatronics etc. This reduction device can be achieved simple parts configuration compared with conventional type. Experimental setup was made for three types of wave generator of different materials. Variation of running torque was observed in the high-speed rotation. In addition, pressure distribution of the oil film in the sliding surface was analyzed.

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The compact and high-power actuator developed by the author is a key part of the device; Active Compliance device. The device is set between a robot and an end effector to enable soft handling. This actuator has some of the following features. This actuator has triple coils, twin magnets, and ball splines. This has made generating high-power and flat thrust characteristics in a compact structure realizable. Linearity of thrust is kept and magnetic flux saturations is constricted during high current. A temperature elevation of this actuator is reduced by the improvement in efficiency of the motors. In addition, the stiffness of the moving part is strengthened. And power consumptions during non-working hours have been lowered. In this paper, we introduce the structure of this actuator and explain the features described above.

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It is considered that robots used in life space need portability, quickness and high compliance as important factors to ensure safety and usability. To satisfy these factors, the reduction of mass of robots is focused in this paper. As a method of lightweight for robots, several soft actuators made of rubber material have been developed. In our researches, very lightweight and flexible pneumatic actuator has been developed by using inelastic films. We already developed bending type actuator using pleats structure. This actuator can bend without rigid links. Therefore, development of power assisting orthotics that doesn't require the exoskeleton is expected. This paper describes a new bending type soft actuator with pleats and bags structures. It seems that more powerful actuator by contraction of bags structure would be effective for wearable robot.

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Liquid nitrogen temperature is an important environment in biological and medical scientific areas. An actuator which has a high safety in a low-temperature environment is required. In this study, we fabricated and evaluated a soft film actuator for a liquid nitrogen temperature environment. The actuator was made by using polyimide films. The fabricated actuator generates a bending motion by applying positive pressure. A bending angle and generated torque of the actuator were formulated. Additionally, these characteristics were evaluated at room temperature and liquid nitrogen temperature. A bending deformation of the actuator was generated when a deferential pressure was about 3 kPa. Compared with a driving performance at room temperature, the performance at liquid nitrogen temperature was decreased. We have succeeded in driving the actuator at 78K.

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We propose a miniature micro motor using the stator that is a cube with a side length of one millimeter. The proposed motor uses a three-wave mode generated at the circumference of its hole, unlike bending vibration modes that is often used in existing micro ultrasonic motors. In this paper, we built an experimental setup and study how to improve of the torque and stability. The motor performance is compared with the analysis based on the Coulomb friction law.

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Pneumatic systems are used in several areas, such as industrial machines, rehabilitation tools and medical robots. However, conventional pneumatic systems become complicated because pneumatic systems have many electrical wires. To solve this problem, we have proposed a Multiplex Pneumatic Actuator Drive Method. This method needs two technical challenges; acoustic communication system and power supply device for each local module. In this paper, small control modules have been developed. When air supply line is 2.5[m] long and the air pressure is 600[kPa], the prototype system successfully works to control ten pneumatic actuators independently without any electrical lines. Therefore, prototype system works very well to show the gTeat potential of this proposed system.

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The advantages of pneumatic rubber actuator are good elasticity and light-weight. Thus, it is easy to implement it over the human body. However, conventional one needs a big compressor, which produces portability problem. With tube-free pneumatic actuator it is possible to have a precise control of pressure and its structure is formed by membranes which consist of polymer and platinum. Besides, the flexible electrode structure acts as a polymer actuator, having the potential of hybrid driven. In this paper, a new portable pneumatic actuator based on reversible chemical reaction is proposed and we show that a faster response time is performed by increasing the membrane area ratio.

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We have studied biohybrid systems integrating artificial components and microorganisms having high functions to improve the functions of microsystems. To increase controllability of such microsystems, we developed a magnetic actuation mechanism using a magnetic structure and an outside magnet. Water-soluble sacrificial layer was patterned by lift-off to release a structure from a substrate. Photoresist mixed with magnetic particles was spin-coated on the sacrificial layer and patterned by photolithography. The structure was assembled in a microfluidic chip. The layer was dissolved in water to release the component. We characterized the actuation of the magnetic structure by magnetizing the component.

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In recent years, a long and slender robot arm is required for entering narrow space while avoiding obstacles and doing various works such as inspection and searching at nuclear power plant, collapsed building, and so on. In this research, we established the design method of the robot arm that will be longer, lighter and slenderer than any other previous research and products with pneumatic McKibben artificial muscles which are quite light, compared with normal actuators such as a motor. Besides, toward the final objective length, 20m, we have made about 3m prototype of the robot arm and did the driving experiment of it.

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Measurement of contraction displacement of the pneumatic artificial muscle is generally using the distance sensor. However, when we use the distance sensor, system is increasing in size and pneumatic artificial muscle cannot be exhibited to flexibility. In this study, for the purpose of solving the problem, we have developed an axial displacement measuring device. This device utilize the relationship between the axial displacement and the radial displacement of the pneumatic artificial muscles. In this paper, we evaluate the measurement accuracy of this device and we confirmed the usability to measure length of the pneumatic artificial muscle.

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This paper proposes a mechanism of rotary actuator using three pneumatic artificial muscles. The mechanism consists of three pneumatic artificial muscles, an eccentric cam, an output axis and a base. It generates a rotary motion by sequentially shortening the pneumatic artificial muscles attached to the eccentric cam. This paper presents the structure of the prototype mechanism and the evaluation of the rotational motion.

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Recent years, the assist-equipment for the purpose of the living support and nursing care have been developed. That equipment usually used rubber actuators. In conventional researches, pneumatic plastic-film soft actuators are proposed. It is considered that pneumatic plastic-film soft actuator is effective to use for assist-equipment from advantages which are lightweight, flexibility and driving at low pressure. However, this actuator does not have sufficient characteristics in order to use for the assist-equipment. This paper focused on improvement of the responsiveness as one method of solving this problem. The principle of the micro-valve structure for plastic-film soft actuator is proposed, and basic experiment using the actuator is described.

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It is well known that a robot driven by McKibben pneumatic actuator (MPA) accomplish various and stable motion in spite of its simple control. However, the control and design of these robots depend on trial error. The important property of MPA for stable motion has not been discussed sufficiently. First, we investigate a periodic motion stability of planar-legged robot that consists two links and two MPA. Second, we propose an input design methodology of antagonistic MPA pair for simple periodic motion. Finally, we verified the validity of these results via experiments with the developed robot.

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In this paper, we investigate the relation of dynamic property between tension, contraction velocity and length of McKibben pneumatic actuators via some experiments. Although robots with McKibben pneumatic actuators are widely applied to rehabilitation, it has not been well verified how do their properties exhibit stable motions from its simple structure. We analyze the relation of output tension, contraction velocity and length. From the results of experiments, we conclude that the dynamic property depending on velocity of the actuator has relation to both the velocity and the length of the actuator and the general form from the relation can be approximated as the plane.

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The purpose of this study is to develop a light-driven SMA actuator. The shape memory alloy (SMA) actuator has many features such as a dynamic displacement value and a large generative force. Driven by the light, the SMA actuator can be downsized and used in many specific environments. In the previous study, the operation was limited to one direction moving. The actuator for driving on both directions is fabricated by replacing the SMA wire to the SMA plate. However SMA plate actuator cannot generate restitution force. To design the actuator structure, driving condition was simulated. Attaching a copper film as bias, the SMA plate actuator can recover the deformation to the initial state. Furthermore, SMA gripping actuator was fabricated and evaluated experimentally.

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Currently, there has already been dynamic characteristic model of the straight-fiber-type artificial muscle using air pressure. However, this model doesn't take into account the effect of air tube. Air transmission delay with longer air tube, and so response of artificial muscle changes drastically. Thus, it is impossible to apply this model. Therefore, in this paper, we built a dynamic characteristic model of the straight-fiber-type artificial muscle that is considered the effects of pneumatic tube for long distance. Then, setting artificial muscle of the earthworm type robot for 15A piping inspection that we have studied as a target, we compared the constructed model with the experimental values. As a result, we confirmed that this model can predict the response of the drive unit to some extent.

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In this study, we describe design and development of dead-reckoning navigational system for the mechanism. The mechanism has two Y-shaped electromagnets (EMs) and six piezoelectric actuators (PAs). This mechanism moves like an inchworm when sinusoidal displacement of PAs and rectangular sticking force to a floor of EMs are synchronized. We measure relative displacements in X, Y, and θ axes between two EMs by three optical linear encoders as its internal sensor. We also measure the mechanism's position and posture from CCD-camera image by an image analyzer to check the navigational performance of the inner sensor. In experiments, we make the mobile mechanism follow an octagon path with 45 degrees rotation at every apex by the inner sensor. We also discuss basic design and expected performance of combination of the inner and outer sensor based tracking control for applying this tiny mobile mechanisms to bio-medical and chip parts assembling applications.

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This paper reports improvement of pressure tightness and the number of contraction of Rubberless artificial muscle. To improve pressure tightness, polyester sheet was sewn to make it a cylindrical shape. In addition, wrinkles on the air bag sheet are reinforced by Kevlar strings. The net sleeve was replaced to Clean CutR sleeve to avoid plastic deformation and flaying. By doing these improvements, the lifetime of displacement achieved over 200,000 times.

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Pneumatic actuators have several advantages: high compliance, lightweight, safety, and low-cost. However, because pneumatic actuators have nonlinearity, the control of pneumatic actuators is very complex. Therefore, high controllability and high response devices are demanded. We have designed the flow control valve that can control flow rate smoothly. This flow control valve has simple structure using PZT resonance mode. In this paper, we aimed at stability of flow rate of the valve, and designed new orifice plates. From the results, we verified the condition to steady flow rate of the valve.

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This study proposes a high-speed locomotion mechanism for a pipe-inspection robot. As a result of the narrow and complex structures of pipeline networks, it is difficult for robots to move quickly within the pipes. The new pneumatic mechanism proposed here realizes high-speed locomotion along with advantageous features for pipe inspection including a small diameter and flexibility. First, we present the design concept of the novel locomotion mechanism using pneumatic flexible hollow-shaft actuators, which was previously developed by the authors. The prototype constructed to realize this concept and the associated mathematical model are then introduced. Second, the basic characteristics of the proposed mechanism are evaluated in terms of the holding force and the impellent force. Finally, the in-pipe movement performance is confirmed. The experimental results show that the designed robot can be propelled inside a 53-mm-diameter pipe at a maximum speed of 250 mm/s, which is exceedingly faster than conventional designs.

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Recently, the studies of life support robots have conducted actively. These robots have robot hands to assist the elderly and disabled people also and are required intrinsic safety, because there are many cases to contact mechaniually with humans. On the other hand, they are need to grasp various shape objects because there are wide variety in the living space. Conventional robot hands what can grasp such an object, are often consisted of the metal frames, electrical motors and gears in order to keep accuracy. These mechanisms are inevitably complex, high weight and stiffness. If the robot hand is a high weight, the moment to elementary part of manipulator is increased. For example, when these robots operate near people, it is also necessary to do at low speed to ensure safety. This case could make work efficiency down. Therefore, it is desirable that robot hands are lightweight and soft. We propose the extremely lightweight and soft robot hand using a pneumatic driven thin plastic-film actuator based on pleated structures. In this paper, the basic properties of the extremely lightweight and flexible the prototype robot hand, it is an object to be experimentally clarify the gripping force and holdable shapes.

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In this paper, we describe design of precise 3-axial servo controller for an inchworm mobile mechanism and simulation result of 1 axis control for checking the validity of the design. The inchworm mobile mechanism is composed of 6 piezoelectric actuators (PAs) and a pair of electromagnets (EMs). If one EM is fixed to a ferromagnetic floor, another EM can position X, Y, and Θ axes by 6 PAs. In previous study, we have developed 3-axial proportional-integral-derivative (PID) control with 50nm resolution for the mechanism with 4 linear encoders for measuring 3DoF motion of the free magnet precisely. However, we conclude that we need over 100ms of settling time because of mutual coupling effects among X, Y, and θ axes by PID controller. In this paper, we propose new design of servo controller to be robust against the disturbance and also reduce settling time, by using combination of bang-bang control and state feedback control. In this controller, we aim at establishment of 3-axial servo control in nanometer scale that can realize ±0.5μm positioning repeatability, and less than 10ms of settling time in 50μm×50μm of positioning range for getting sufficient working efficiency.

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This paper proposes a manipulator which can generate a translation and rotation of fluid field. It can translate and rotate an object. Its structure is simple and it consists of 2 plates with lattice-shaped air holes. We show its structure and principle of operation. We have experimentally verified that the manipulator can translate and rotate a variously-shaped object

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In this paper, we suggest a body weight cancelling system using rubberless artificial muscle. This system reduces torque due to the mass on lower limbs by hanging a person with rubberless artificial muscle. The control procedure to hang by constant power was suggested to perform stable body weight cancelling in this system. In addition, we aim to perform appropriate body weight cancelling in walking. Therefore, the validity of principle for detecting horizontal force was confirmed experimentally. From the above-mentioned result, the realization of a system performing body weight cancelling appropriately corresponding to the movement of the person is possible by indicating the procedure that we suggested.

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In this paper, a lightweight master interface for a surgical robot system is proposed. The position of the human hand is measured by a non-contact motion tracker, but the force feedback is realized by a handheld haptic device. A gripping force is displayed by a pneumatic bellows, which is smaller and more lightweight than electric motors. As for the slave manipulator, the gripper of a surgical forceps is actuated using a pneumatic cylinder. Force estimation is possible due to the back-drivability of the pneumatic actuator. Experimental results show the control performance of the haptic device and a constructed master-slave system.

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Contact state of upper and lower teeth is very important for diagnostic treatment of occlusal disorders. This paper discusses an actual occlusal motion with patient-specific 3D-motion display system. The system uses a patient-specific hybrid model to analyze detailed contact state of upper and lower teeth in eating foods. The hybrid model consists of maxillary and mandibular bone data with cone beam X-ray CT and precise teeth shape data with industrial X-ray CT. The proposed display system clearly shows the trajectories of each tooth and the guide function.

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In reconstructive surgery, thin blood and lymph vessels of about 1 mm in diameter are frequently anastomosed. Such tasks demand high dexterity of surgeons, but there is the problem that their dexterity decreases because specific surgical sites (submandibular region, nasal cavity, etc.) force them on awkward posture. A master-slave system may solve this problem because the master and slave can be separately arranged and surgeon can operate in comfortable posture. Therefore, the purpose of this study is to develop a master-slave system for reconstructive surgery. In this paper, we illustrate mechanical design of the developed slave manipulator and experimental results with this manipulator. The experimental results show that the developed manipulator has the resolution of less than 10 μm, the band width of 〜 Hz, and the master-slave system has good tracking property.

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While liver RFA treatment is minimally invasive, it is difficult for surgeon to confirm the ablated area on ultrasonic image. For accuracy improvement of RFA treatment we proposed an ablation supporting system for RFA. In this paper we discussed how the time interval affects the accuracy and analysis cost in the system. According to the experimental results under different time interval conditions it is suggested the time interval 30[s] was efficient to realize the goal temperature of the certain location close to the needle.

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For the longevity of total knee Replacement (TKR), it is important to predict the wear of polyethylene insert. The aims of this study were to show the mechanical properties of artificial knee joint using computer simulation of KneeSIM, and to evaluate its usefulness. Kinetic condition of computer simulation used the ISO data for wear test. Configuration parameters of KneeSIM were set to be correlated with the computer simulation result and ISO data, then, it was evaluated the force applied to the components. For the simulation of KneeSIM is included soft tissue, ligaments and patella, parameter settings need to be explored. However, computer simulation we proposed was there is a possibility that can evaluate the mechanical properties of the artificial knee joint.

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In the field of regenerative medicine, 3-D tissue engineering, which intends to regenerate lost tissues and organs, is mainly focused. We have already established a technique to make a 3-D construct only with cells. Cells construct is made by spheroid-culturing the cells and neatly arrange the spheroids. Namely, quality of spheroids is important. If there is a difference in the number of cells when dispensing the cells turbid liquid, spheroids in different sizes are generated. Therefore, this study was aimed to develop the spheroid morphological evaluation system. We used mesenchymal stem cell of rabbit. Upon reaching the required number of cells, we were dispensed into the special multiwell plate for forming spheroids. We analyzed the quantitative evaluation about spheroids using the developed system. In result, it was found that there is a range of cell number to form spheroids with high degree of circularity.

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We have proposed a force rendering method for palpation motion based on the haptic enhanced reality method. In this method, the force from a haptic device overlaps the reaction force from a base object. The key idea is to use a base object that has a material property similar to that of the target and to combine the virtual force produced by the haptic device with the reaction force from the base object. The purpose of this study is to develop a laparoscopic surgery training system for using the haptic enhanced reality method. In this paper, we describe the methods of contact detection and virtual force generation with a three-dimensional surgical phantom.

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In performing the finger joint ligament repair, became possible method using anchor. However, cases where the anchor loses have been reported. The purpose of this study was to evaluate about withdraw of anchor under simple tension and cyclic loading conditions. This experiment were performed using an evaluation simulator for clinical material we developed, and target was the anchor of the JuggerKnot. In the simple tensile test, the materials were pulled in 0.1mm/sec until rupture. In the cyclic loading test, the materials were pulled 200 times in 0.5Hz between from 10N of 30N, subsequently a simple tensile test was performed. It was found from the result that the strength of the anchor was improved by given repeated moderate load.

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Interventional radiology is a minimally invasive image-guided procedure that can be performed percutaneously. When computed tomography (CT) is used as an image-guidance for interventional radiology, the radiation exposure is a major problem to an operator who stands close to a CT gantry. To solve this problem, we are developing a remote control needle puncture robot which has five degrees of freedom. However, evaluation of the positioning performance of the robot was not conducted. In this paper, evaluation criteria of positioning performance required for a needle puncture robot is determined, and the performance of the robot is evaluated.

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Water-Filled Laparo-Endscopic Surgery (WaFLES) is a surgical technique which is performed by irrigating the abdominal cavity with liquid. By applying WaFLES to laser surgery, heat effect from the laser irradiation is reduced by cooling effect of the fluid irrigation in abdominal cavity. However, it is difficult to perform laser irradiation accurately inside the abdomen, because the organ is always floating in water by buoyancy. Therefore, we introduced a surgical robot system that enables a high-precision laser irradiation to a moving organ in abdominal cavity. In this study, as a basic technique we developed a system which measured organ motion in abdominal cavity filled with a liquid and then evaluated the usefulness of this system. Experiment results show that the motion error is about 0.3-0.6mm and the computation speed is about 56ms.

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In order to avoid infections caused by a percutaneous power supply cable for an implantable artificial heart, we propose a wireless power transmission system utilizing a magnetic resonant coupling technology, which can transmit electric power with wider gap than that in an electromagnetic induction technology. In order to compensate for decreasing the transmission efficiency due to the relative movement between a transmission coil and a receiver coil, coupling coefficient between the coils is enhanced by controlling attitude of the transmission coil according to the position and attitude of the receiver coil. In this study, effect of enhancing the transmission efficiency owing to both controlling the attitude of the transmission coil and matching the impedance was evaluated. Moreover, a motion capture Kinect is used for measuring the position and attitude of a patient implanting the receiver coil. The measurement accuracy of the Kinect was evaluated.

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One of the clinical treatment of heart disorders has myoblast cell sheet transplantation. Because the myoblast cell sheet is weak, it is difficult to transplant it without the damage. There a device of the scooping mechanism which can be moved without breaking the cell sheet was developed. However, it is difficult to transplant the cell sheet to beating heart with it. We have developed the surgical robot with a heart-surface-motion synchronization mechanism for myoblast cell sheet transplantation. The purpose of this study is to develop a new robot having the bent for clinical application, which applied scooping mechanism to its transplant mechanism. A success rate and an average damage score in transplant with the robot system under experimental environment became 60% and 99.5±4.2%, respectively. The results of transplant simulation with an imitation cell sheet show that our robot system is better than manual operation using the device of the scooping mechanism.

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To decrease human error of the pericardiocentesis, we aimed to develop the pericardiocentesis assistance device. Purposes of this paper are to design of the pericardiocentesis assistance device. We proposed the new pericardiocentesis assistance device that needle was not used. The proposed device is able to aspiratethe fluid in pericardial space by cutting the pericardium using the cutter. To cut the pericardium, we designed the two type cutter that are the stress type cutter and the shear type cutter. As the result of two type cutter comparison experiment, the shear type cutter was able to cut the mock pericardium.

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Pericardiocentesis-assist device is necessary for reducing medical accidents. One of the elements constituting the pericardiocentesis-assist device is a gripping mechanism of the pericardium. In this study, we aimed to identify the force that the proposed device could hold the pericardium without slip. Static friction force between the pericardium and a stainless steel and elastic force of the pericardium were measured. Grip force was determined to 20.3N.

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Vitreoretinal surgery is one of ophthalmic surgery. Recently, the ophthalmic endoscope is sometimes used in vitreoretinal surgery. However, it is difficult to operate while using the ophthalmic endoscope in vitreoretinal surgery. Therefore, the robot which holds the ophthalmic endoscope is required. Here we present the design of a robotic holder for the ophthalmic endoscope and its control method. In addition, an experiment have been carried out to test our presented control method and the result suggest the effectiveness of our presented control method.

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In recent years, the elderly population has steadily increased. In particular in Japan, the progress of the aging is proceeding at a rapid rate in comparison with other developed countries. Surgeries to elderly people carry a lot of risk, and there is a need for measures immediately. We have been developing a support system of liver surgery using IT technology. In this study, we focus on the measurement method of a knife tip during surgery.

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A new manipulator with a detachable commercial forceps has developed that can act as a third arm for a surgeon situated in a sterile area near the patient. A mobile locally operated detachable end-effector manipulator (LODEM) with back-drivability was developed and tested. This device uses electromagnetic brake for pitch and yaw axes, and wire transmission for insertion axis to achieve both manually-operable and motor-drivable manipulator. The mass was 5.8kg. The manually-operable force was less than 10N, sufficient for back-driving arm. The motor-drivable force was more than 10N, sufficient for pulling organs. The positional accuracy was 0.5mm, acceptable for handling organs. A mobile LODEM 3.0 was designed that allows minimally invasive robotically assisted endoscopic surgery.

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In this paper, a robotic laparoscope with three degrees of freedom which can be added to the surgical robot for single port surgery (SPS) developed in our previous study and enables the surgical robot to form the arrangement of the surgical instruments called rotation formation, was developed. In order to control the tip position of the robotic laparoscope in the direction which the surgeon intends, the kinematics of the robotic laparoscope was analyzed. Then, based on the inverse kinematics, a position control system using the PID controller was constructed. The experiments on the tip position tracking control for the robotic laparoscope were executed using the haptic device Omega.7. It was verified that the operator can control the tip of the robotic laparoscope intuitively and the tip position of the robotic laparoscope can track the target position accurately.

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In Japan, one of the major causes of death is vascular disease (stroke). If the patient stroke movement disorders such as hands and feet paralyzed prone, the limbs were allowed to stand, would be joint contracture. We develop a hydraulic rehabilitation equipment using a bellows for the purpose of preventing finger contractures. Rehabilitation equipment has the mechanism that allows hands and fingers flexion and extension automatically. In this report, we rethink the mechanical section of rehabilitation equipment, and develop a new mechanical section of rehabilitation equipment.

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In this study we developed a pneumatically-driven manipulator of the master-slave-type surgical robot. The manipulator has dual flexible joints and be capable of grasping and bending the tip in two degrees of freedom by two pneumatic cylinders. Considering the interoperability in real surgery, we proposed a mechanism so that the clean forceps part can be easily attached to and detached from the filthy drive unit. To verify the tracking performance, we actually conducted an experiment of the master-slave-system with the proposed manipulator.

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Recently, surgical robot is used in biliary-pancreatic surgery. However, complications, such as failure of the sutures, occur frequently. Therefore, we propose a membrane suture supporting system that prevent from unintentional needle penetration that cause failure of the sutures. Our strategy is that predict the ease of needle penetration through membrane from strain of that. We investigated relationship between strain of tissue isolated from porcine jejunum and penetration force by needle insertion experiment. As a result, the following relationship was suggested; when the strain increased at a constant rate of change, the penetration force became constant, however when the strain exceeded a certain value with the tension, the growth rate of the strain decreased, and the penetration force decreased.

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A new manipulator with a detachable commercial forceps has developed that can act as a third arm for a surgeon situated in a sterile area near the patient. A compact locally operated detachable end-effector manipulator (LODEM) with linear and circular slide mechanism was developed and tested. This device is a spherical-coordinate manipulator and uses circular stair-like slider for yaw and pitch axes, and linear telescopic slider for insertion axis to make wide working space on abdominal wall. The mass was 250g. The shortened size was 180^*60^*60mm and the expanded size was 230^*100^*60mm. The positional accuracy was 0.2mm, 1.2mm and 0.5mm respectively. A mechanism of compact LODEM was designed that allows minimally invasive robotically assisted endoscopic surgery.

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Microbubbles are expected as earners of acoustic targeted drug/gene delivery therapy. To realize the therapeutic system, we have proposed a technique that controls microbubble behavior in blood vessels using ultrasound emitted from the body surface. To apply this technique in vivo, robotic ultrasound transducer positioning on body surface is required. For this purpose, we have developed a robotic system to determine contact between the body surface and transducer, but adhesion of the surface of the transducer was not guaranteed. To address this issue, we propose a control system considering surface contact using reaction force and moment. We performed evaluation experiment of this system including self-weight moment compensation. As the result, we confirmed surface contact on body surface and the transducer.

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We have developed a prototype of quantitative vibratory sensation testing device in medical and rehabilitation fields. The vibration perception inspection using the tuning fork, it would be difficult to carry out inspection by Angle of tuning fork or the force that hit the tuning fork of examiner. Our goal is to perform acceleration feedback control of the vibration generator and to complete the quantitative vibratory sensation testing device. This paper presents results of the acceleration measurement of the vibration generator for perform the acceleration feedback control.

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The silicone retractor attachable to suction pipe was developed [1]. However, force sensing is also preferable in order to avoid the damage on brain tissue resulted from unexpected large force. With this in mind, this paper presents force sensing system attachable to suction pipe. The developed system has three functions of suction, retracting, force sensing at the same time. The sensing system was based on force visualization mechanism displaying force as a motion of colored poles. From the poles motion, Surgeon can then roughly understand the magnitude of retracting force. With camera in fiberscope, the retracting force can be measured with the resolution of 0.05 [N] until 0.3 [N]. The force visualization part was made of silicone, and then has the merit of disposable, low cost and easy sterilization. We showed the validity of the system by FEM analysis and experiment.

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