In the previous researches, a 6-wheeled mobile robot employing the linkage mechanism, "Zaurus", has been developed to extend maneuverability of wheel type mobile robots. Neural network and PID controllers are introduced as the control system for Zaurus, and their performance are compared. In this research, neural network and PID controllers are redesigned, because the experimental results using Zaurus are different from the results of simulation. The results of the simulation and experiments using Zaurus have improved by introducing the models of motor driver.

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The swarm intelligence such as cooperative transportation and collision avoidance is actively researched for cooperated operation by many robots. This paper describes development of small mobile robot "WITH" which can be moved to Omni-direction, and each part is modulated.

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A mobile mechanism using wheels is one of the most popular mechanisms for mobile robots. Because, its energy efficiency is high, mechanism is simple and the control system is well investigated. However, the wheel type mobile robots have difficulty in the rough terrain movement. In the previous research a 6-wheeled mobile robot employing the linkage mechanism, "Zaurus", has been developed to enhance maneuverability of wheel type robots. In this paper, we propose an environment recognition system that selects optimum controller for Zaurus in each environment. This system using the self-organizing map (SOM) is fed the linkage data because the Zaurus has linkage mechanism which changes the shape according to the environment.

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The systematic classification method of hand motions, which indicates the minimum mechanism of robot hands, is suggested. The performance of existent robot hands is not as high as that of human hands because the performance of existent actuators does not come up to that of human muscle in the same volume. It is important for robot hands to accomplish aimed tasks with their minimum mechanism. Human hand motions are analyzed quantitatively in consideration of robot hand mechanisms such as engagement mechanism of DIP joint and PIP joint. According to the results of analyses, three items, that is, needed fingers, joints which need to be set up actuators and fundamental movements which we define in this study are got. Moreover, the figure of systematic classification of human hand movement for robot hand by three items is created.

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This paper presents the development of simple structure and light weight robot finger which can grasp various shapes of objects by self adapting to their shapes. This finger was designed for grasping object which is used in daily life, in order to use for prosthesis. This finger consists of three phalanges, interconnected by the joints of leaf spring. The three phalanges are driven by a single tendon. First, mathematical model of the finger was constructed in order to optimize dimensional design for distributed forces to each phalanx. Second, finger was made and grasping experiment was made. Finally, the results of maximum ejection force for the finger are presented.

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In this paper, we consider a grasping method for robot hands including the uncertain center of gravity (COG) of an object, based on numerical analysis. Such a method has robustness and stability for grasping, and we will be able to achieve high generality robot hands.

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Human hand is a multifunctional end effctor which is widely used for various purposes. The purpose of our study is to realize dexterous manipulation task with universal robot hand system which has the same capability as human hand. In this report, we propose the strategy to hold object and technique of optimize the torque or pressure value. In the evaluation experiments, the system could rotate the wheel object dexterously.

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Recently, a robotic hand with tactile sensors is important for manipulating objects dexterously. However, computer resources are needed for processing tactile sensor information because tactile sensor has numerous measument points in general. For resolving this problem, this paper proposes a fast sensing method with the genetic algorithm. The validity of the proposed method shows in some experiments.

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This paper describes an accuracy of shape recognition in rotating manipulation. First the time-series pressure distribution is messured with a distributed pressure sensor on the universal robot hand. Kurtosis is calculated from a pressure distribution, and the time-series kurtosis in a rotation manipulation is found. Second the time-series kurtosis is cut out with the feature kurtosis values to obtain short kurtosis patterns. The degree of similarity between these short kurtosis patterns using the DP matching recognizes the object's shape in rotating manipulation. We confirm that the recognition accuracy is high through experiments.

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The Harmonic Drive^[○!R](HD) has been used in the market of FA and measurement devices. In these markets, the customer requirement is smaller gear-head and actuator. We developed more small gear head CSF-3 and AC servo actuator RSF-3A corresponding to the customer demand. The key technology of development for CSF-3 and RSF-3A is as follows. CSF-3: Manufacturing technique, Measuring technique, and Overcoming of wear problem of early stage. RSF-3A: Achievement of High density alignment coil, Development of thin type encoder, and Assembly technique. The world smallest gear head CSF-3 with the feature of zero backlash, high accuracy and high torque has been commercialized by these key technology was established. Additionally, RSF-3A with the feature of small and light weight has been commercialized, too.

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In this study, we propose a strategy of knotting using a high-speed multifingered robot hand and tactile sensors. The strategy is divided to three steps: a loop generation, a replacement of ropes, and a pulling of a rope. Through these three steps, a knotting is achieved by only one multifingered hand. And, in order to allow the continuous motion, we have added one step: "a shift of rope". The experimental results are shown using the multifingered hand with tactile sensors. Finally, we analyze a behavior of the replacement of rope to produce a high rate of success.

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In this paper we develop a tendon-driven robotic hand. This hand is composed of a three DOF thumb robot and a four DOF forefinger robot. The thumb robot is controlled with four tendons. The forefinger robot is controlled with four active and two passive tendons, which are useful to realize biomechanical features of human forefinger. The DIP and PIP joints of the forefinger robot are realized interlocked motion in non-contact tasks, and move independently in contact tasks. This paper shows the basic kinematics of the proposed tendon-driven mechanisms and designs prototype models.

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This paper designs human interface of a supervisory control system for a robotic hand. Slave controllers are designed for preshaping, pinching and orientation control of grasped objects. We chose Data Glove as master device beacuse of without remake master device. The Data Glove doesn't map hand configuration but minimum information for operation. We propose the model of human hand and the method for orientation control of grasped objects by the Data Glove, experiment using real machine and validate the method.

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Students becoming therapists have less opportunities of repeated training with joint contractures. A robot hand for the education/training of rehabilitation has been developed. This paper presents a model of adhesion joints, which is one of the joint contractures. The robot hand imitating adhesion joints is controlled by the force control based on torque control. The effectiveness of proposed method is demonstrated by experiments.

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In this paper, we consider which posture of grasped object is best when we grasp it by pinching with friction. Up to now, we have analyzed this issue for circular object in the 2D grasping with two fingers. Here, we consider the grasping of rectangular object. As case of the circular object, we obtained a similar conclusion that the optimal posture is determined by the two friction cones at the two contact points.

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Impact manipulation can generate a large force in a moment. Therefore it is effective for press-fitting operations. In this research, we model a press-fitting and analyze it for realization by robot manipulator. We analyze the relation between hitting velocity and press-fitting depth. A necessary hitting velocity for a desired press-fitting depth can be obtaind by the relation. We adopt an under-actuated manipulator for hitting at the sweetspot. Simple Genetic Algorithm is introduced to plan a manipulator motion to generate a desired hitting velocity. We experiment press-fitting operations to drive an under-actuated manipulator to the plan.

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Some environmental contact tasks by a manipulator need large static force; such as press-fitting and inserting connector. Then, We propose and design a novel end-effector for a small manipulator to generate large force, and analyze the force generated by the end-dffector. In addition, We devise a method to increase a stroke. Finally, to move heavy objects by a position controlled manipulator, we introduce to motion planning methods with this structure in consideration of manipulator torque and compare them by total motion time.

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The report introduces the hardware to attach the multiple sensory bilateral control systems. For the multi-finger hand which is remotely controlled not only vision but power feelings by master-slave method. At this work, the constructions of the unilateral control systems are conducted to a remote teaching systems, and manufacture of a master glove are reported.

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This paper presents a new mechanism for artificial fingers. It enables a rotation of adduction/abduction of the MP joint in addition to the flexion/extension of the DIP, PIP and MP joints. The key mechanism is the newly invented Double Planetary Gear System (DPGS) that allows three DOF motions of the finger in a compact placement of all actuators in a palm. The planetary gear system receives two input torques; one is an active torque coming from DC-motors, which activate solar gears, the other is a passive torque generating around the carrier of the planetary gears. This active/passive hybrid actuation enables a gripping with unknown shape object with no sensory feedback. This paper describes the kinematics and the kinetics of the newly developed mechanism followed by the kinetics of pinching the object by two-fingers. It also shows the results of a couple of experiments. Additionally, we show a new mechanical design aiming for constructing a multi-fingered hand.

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This paper discusses a dynamic manipulation for a disk-like object on a single gripper plate, where both the position and the orientation of object are dynamically controlled. The main driving force for manipulating the object is produced by the combination of inertial and frictional forces. We first explain how to control the object for the desired position and orientation. We then show an experimental result for confirming the basic idea, where we utilize a high-speed single gripper manipulator with the assistance of a high-speed vision.

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This paper discusses a piercing based food handling robot where two needles are inserted into a food and a palm presses the food. Such a piercing type hand has a potential to grasp the food even in the case where the food is put into a lunch box. There are two ways for piercing foods, one is the inner directional arrangement where two needles are implemented so that they push object through the piercing force, and the other is the outer directional arrangement where two needles are implemented so that they pull object. We found that the outer directional arrangement is more effectually working from the viewpoint of the firm grasping.

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Until now, various robot hands have been proposed and developed. However, diversity of human skills has not been achieved. Utilization of tools can be considered as one of solutions, because human being utilizes various tools. However, it is very difficult to handle the various tools for a robot hand. In this paper, a novel hand mechanism is introduced. The proposed hand can handle various opening and closing type tools e.g. pliers, nipper, scissors. Its concept and design are introduced.

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We present our 3-D cam transmission mechanism designed for developing a non-backdrivable robotic finger with strong gripping force. The modification of the cam dog frame of the cylindrical-cam has reduced the backlash in the contact surfaces within the cam. Experiments show that the positioning error is similar to that of the gyro-cam mechanism, which had minimum error. The dynamic characteristics of the two cam dog shapes are described by comparing their rotational displacements of the joint and motor shaft. The gyro-cam shows a better response, and cylindrical cam needs further adjustment and lightweight solution.

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This paper proposes a method that a multi-fingered robot hand realize in-hand manipulation performed by a human hand using a principal component analysis (PCA) of joint angles. The numbers of dimensions calculated by the PCA and the reconstructed hand postures between human and robot hand are compared. The result showed that the number of dimensions of the robot hand closes in the number of the human hand.

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The purpose of this research is to develop a teaching system for a multi-fingered robot hand. First, this paper describes a recognition method for manipulation using the contact state transition on the palm surface. Second, the teaching system is developed by using the recognition method and a multi-fingered robot hand "NAIST-hand" developed by us. The experimental result showed that object manipulation is realized by the robot hand by transferring the primitives recognized by the method.

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In this paper, we investigate a ball pitching motion as one of human's dexterous object manipulations. We present a contact model between a robot finger and a ball, and calculate the driving force of the finger for obtaining a desired direction, velocity, and angular velocity of the ball.

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In this paper, we propose a passage algorithm through a narrow space for Autonomous Mobile Robots. We form a steady formation by making Delaunay-Diagram using profiles of surrounding robots. And we resolve deadlock by using the phase gap of Nonlinear Oscillators that input profiles of surrounding obstacles. We verified the effectiveness of the proposing system by simulations and experiments.

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This paper is intended to intensively discuss how intelligence of real-time adaptability can be designed from perspective of "embodied system". One of the significant features of our approach is that we explicitly exploit an "emergent phenomenon" stemming from the interaction between control and mechanical dynamics in order to control locomotion in real time. To start from simplicity, we focus attention on locomotion of a protozoan organism, e.g., slime mold and amoeba, which exhibits remarkably intelligent behaviors, such as avoiding hazardous condition, approaching nutrients and humidity, and solving a maze. These behaviors are based on amoeboid movement, which is driven by the flexible epitheca and the protoplasm in the absence of a central nervous system or specialized organs. In light of these facts, we made a simulation model, particularly focusing on epitheca consisting of "real-time tunable springs" and "low of conservation of protoplasmic mass", the former of which is used to deal with local interaction dynamics and the latter of which is used to deal with global interaction dynamics. Simulation results indicate that the proposed model can induce highly adaptive locomotion according to the situation without losing the coherence of the entire system.

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One of the most graceful phenomena widely observed in nature is self-assembly; living systems spontaneously assemble their body structure through the developmental process. While this remarkable phenomenon still remains much to be understood in biology, the concept of self-assembly becomes undeniably indispensable also in artificial systems as they increase in size and complexity. Based on this consideration, this paper discusses the realization of self-assembly with the use of a multi-robot system. The main contributions of this paper are concerns the exploitation of emergent phenomena stemming from the interplay between the control and mechanical systems, this allows us to significantly simplity the control algorithms required for the spontaneous self-assembly. Preliminary simulation results show that stable self-assembly is achieved irrespective of the initial positional relationship between the modules.

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This paper intensively investigates how heterogeneity of system components influences the adaptability of the resultant behavior by taking a modular robot as a practical example. To this end, we have introduced different adhesiveness between the modules. Simulation resuts strongly support that a certain heterogeniety significantly improves the adaptability that can not be achieved only by homogeneous modules.

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This paper shows the development of precise needle insertion manipulator driven by flexible rack. We aim at the precise positioning of manipulator with drive transmission using flexible rack. The mechanism to realize precise positioning using flexible rack dive is supposed. And, we develop the needle insertion manipulator using the supposed mechanism. The characteristics of flexible rack drive is measured and modeled to make controller. The controller of manipulator is made from simulation result using flexible rack drive model. The experiment to measure the precision of manipulator was carried out. The developed manipulator realizes precise positioning at 20μm.

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This paper shows the development of MRI compatible needle insertion manipulator and guidance control of manipulator using visual information. MRI is used to obtain organ shape, shape of abdominal wall and shape of cancer and to see the overall positional relationship of those tissues. And, endoscope is used to obtain real-time information of organ displacement. The needle insertion manipulator is guided by an artificial potential field approach using these information. The experimental result showed the approach to target tumor was realized.

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The intra-operative evaluation of soft tissue balance in knee arthroplasty is executed with trial components of article knee joint. It is needed for excellent long-term result after knee arthroplasty to confirm the proper soft tissue balance. So to assist surgeon, we proposed the robotic instrument for intra-operative evaluation. This paper reports the in vitro experiment with the robotic instrument that consists of tensing robot and 6DOF measurement of the knee joint. We could adjust the soft tissue balance quantitatively by cutting distal femur seeing the robotic data.

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The clinical target of this study is intrauterine patch coverage of fetal myelomeningocele. The collagen patch is supposed to be stabilized onto the fragile fetal tissue during the laser fixation process. In this paper, a robotic patch stabilizer using wire driven mechanism (2 D.O.F, Max bending angle is 45[deg]) has been developed for precise force control on the patch without damaging fetal tissue. The diameter of the stabilizer's shaft is 2.4[mm] and the length of the stabilizing part is 60[mm].The driving wires are moved using an ultrasonic motor while the tension of the wires is measured using a force sensor. The stabilizing force was estimated by the wire tension with 3.5 % error between the estimated value and the measured value. The future work is to control the stabilizing force using a phantom of fetal fragility.

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In recent year, robotics and computer technology introduced in surgical domain allow surgery to be performed more precise medical care. In particular, computer technology enables precise surgical simulation using virtual reality or computer graphics. In our research, we will focus on constructing an intra-operative navigation system with online information of organs and surgical tools based on surgical simulation with mechanical models. This proposed simulation system consists of two simulators and an actual manipulator: virtual slave manipulator, organs deformation calculator and master controller. In this paper, we illustrated the organs deformation calculator and an experiment with pig liver and this simulator.

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Minimally invasive surgery has recently become a key word in medical engineering. In this operation, to introduce surgical instruments, spatulas which push tissues aside and retain the approach path to the affected area as well as workspace for the insertion of such instruments are necessary. Therefore, a new type of hydraulically-driven flexible manipulator for neurosurgery has been developed. With an attached balloon and using only physiological saline for the drive system, safety of the brain tissue, especially in terms of pressure, is assured as is the simplicity of the mechanism. In addition, this provides the advantage of MRI compatibility. In this paper, we developed the third prototype and constructed the model for sensing the retract pressure.

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We propose a surgical dissection training device that allows residents to repeatedly practice through self-trainings surgical skills needed for exposures and dissections in laparoscopic surgery. The device (100^*100^*8[mm]) is composed of three elements: 1) a pair of silicone membranes to sandwich other elements at the top and bottom which imitate peritoneums; 2) nonwoven membrane(s) placed between the silicone membranes, imitating adipose tissues which can decrease visibility; 3) silicone tube(s) covered with cotton fabrics having a loose weave, to imitate vessel(s) surrounded over with adipose tissues. The mechanical properties are decided to become in accordance with those of actual porcine intestines measured through tensile and peel tests in terms of toughness, elasticity and peeling strength. In addition, a surgical dissection training system was developed, with which residents practice surgical maneuvers, viewing operation fields on a computer monitor connected with a CCD camera. In vitro experiments indicating novices could perform a dissection task after a short training faster than when without any training confirm usefulness of the proposed dissection training system.

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We newly developed a flexable retractor with large contact areas and roundish corners that allows stably and safely manipulating organs in the narrow abdominal cavity. The retractor has been revised in terms of contact safety form and human finger-sized retracting surface design. Compared to earlier ones, it has a smaller retracting surface to retract targeted organs stably while avoiding unexpected physical injury to surrounding ones during laparoscopic surgery. The retracting surface enables to spread from a φ 12[mm] thin bar to 8^*6[cm^2] plane corresponding to areas of four fingers laid close which are used when surgeons make retraction of small intestine in open surgery. In addition, the head of retracting surface is formed to make all projections 120[deg] and have roundish corners to disperse and reduce risks to injure organs. In vivo experiments indicating the retractor enables to easily move away small intestine to identify a targeted rectum without causing any injury and bleeding confirm the effectiveness of the proposed design method.

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Works by multiple robots are expected to improve the task efficiency. Therefore various researches are performed about the cooperation with multiple robots. Against this background, this paper deals with the pursuit problem that is a typical task for multi-agent system. Most of previous studies on multi-agent system assume homogeneous ability of each agent. In our research, individuality of agent abilities is considered for application in real environment. In this paper, we especially focus on the speed difference between preys and the predator, and propose scatter algorithm in order to improve capture rate when speed difference doesn't exist. Several simulation experiments are carried out, and show the effectiveness of the proposed algorithm.

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Tracking control is an essential requirement for robot swarms capable of performing a wide variety of tasks in an unknown dynamic environment. In this paper, we present a cooperative tracking strategy that enables large swarms of robots to split into smaller groups and follow multiple moving goals in the presence of environmental constraints. Using a network of local interactions, the proposed strategy is implemented with two principal functions of both adaptive flocking and determination of a goal direction. During the flocking process, the robots with limited range of sensing are able to maintain a uniform distance to each other, while following multiple moving goals. Finally, we verify the effectiveness of the proposed tracking strategy by computer simulations both in empty and cluttered environments.

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The definitions of life have been advocated since a long time ago, and numerous attempts have been made to explain essential aspects of life from various perspective, such as self-replicative, dissipative, and autopoietic systems. In this paper, we present a novel model of active floating units which can self-assemble on the water surface. We focus especially on the shape of the unit, which is an essential factor of aggregation but difficult to deal with existing frameworks. After several experiments, a unique self-assembling behavior was observed by exploiting several physical-level forces; 6 units which have a cake-cut shape gather into a cluster and form a propeller-like pattern, which is unique to the configuration. This kind of hierarchical behavior is considered crucial to achieve morphogenesis of a multi-unit system. The results shown here provide a good starting point for speculation about the level of autonomy of a unit in the complex environment when the system creates a self-assembling pattern.

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In recent years, traffic accidents have been serious problems. We discuss about traffic accident and catch the relation between vehicles as a mutual reaction relation of an antibody, and propose the traffic accident avoidance algorithm by using the immunity network. In this paper, we evaluate this algorithm by using a micro traffic simulator "KAKUMO" and verify the effectiveness of this system. The vehicles' behaviors were evaluated not only from microscopic viewpoint as safety but also from macroscopic viewpoint as improvement of traffic smoothness

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This paper deals with recognition of object-shape by using signal propagation characteristics along multiple robots attached to the object. The robots have local communication and mechanical function to recognize the difference between object and obstacle. Signal Propagation emerges when sufficient robots surround the object and send or receive a signal. It is found that when the robots surround the object high density, the number of robots receiving the signal changes according to the radius of the object. We clarified the relation between the obtained signal propagation character and the object shape and found that there exists a permissible robot size to recognize the object shape.

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The haptic parameters for a forceps are important in order to develop the laparoscopic surgery simulators. We investigated the forceps's motion and applied force operated by skilled surgeons during the laparoscopic surgery using a sensor forceps. The required haptic parameters of the forceps for the laparoscopic surgery simulators were identified.

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It is very difficult to provide with the belt pulley in a minute structural manipulator joint. In the structure that the belt pulley is not used, the relation of wire displacement joint rotation corner and wire tension-rotating torque becomes nonlinear. The control grows this method, and difficultly it becomes, and the loss of the torque grows, too. So, the moment arm changeable type joint is designed, and it is confirmed that there are appropriate parameters to design linear joint.

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Purpose of this study is the development of surgical robot system with heartbeat compensation. By driving manipulator using the sensing data of the heartbeat, the position and orientation of heart and that of the manipulator are synchronized and relatively fixed. Hereby minimum motion like interarterial coronary anastomosis under the heartbeat becomes possible and therefore it will be minimally invasive. This paper describes the method of heartbeat compensation, master-slave surgical system and heartbeat compensation system. The Shincronaized motion is to make the robot follow to the movement of the heart, the detected heart position is input to the slave robot. The Shincronaized vision is to offer the image of a geostationary heart. We report on the work experiment to combine the Shincronaized motion with the Shincronaized vision.

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In late years, ultrasonic surgical aspirators are used in laparoscopic surgery. Their probes' configuration, which is linear shape, encumbers accurate surgical techniques. We propose a bendable probe that can be controlled at someone's discretion. NiTi alloy and ASTA2^[○!R] ware selected as probe materials, because of their high modulus and low Young's modulus. In this paper, we describe an evaluation of vibration properties of two alloys selected as probe materials by measuring their vibration transmissibility. Compared them, ASTA2^[○!R]'s one was more than 5 times as large as NiTi alloy's. We confirmed ASTA2^[○!R]'s vibration property is of service for this new probe.

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In this paper, a remote surgery experiment between Japan and Thailand using a Research and Development Internet is described. In the experiment, the image and audio information was transmitted by a newly developed low latency CODEC system to shorten the time-delay. By introducing the low latency CODEC system, the time-delay was shortened compared with the past remote surgery experiments despite the longer distance.

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Laparoscopic surgery and catheter surgery become popular as minimally invasive surgery. It is important to develop micro forceps for more delicate operation at the delicate area. Development of micro forceps need advanced processing technology to make minimum parts. Moreover it is necessary to design the holding mechanism that's compose of extremely few parts, and develop the material it's not broken while operating even if the size is downed. In this study we designed micro forceps that's compose of four parts, those are two holding parts (width 0.5mm), an exterior pipe (diameter 1.0mm), and spring (line diameter 0.05mm). Then we succeed in making prototype of micro forceps, it is made by Metal Injection Molding technology.

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Laparoscopic surgery becomes popular as minimally invasive surgery. It is important to develop a functional forceps for more delicate operation. In this study we have designed and developed a laparoscopic surgical forceps with high rigid bending joint. The tip joint has 3 degrees of freedom which are grasping, rotating and bending. The bending motion has been produced by linear slide of two half-outside pipes. Both feasibility and effectiveness of this forceps were verified experimentally.

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