When the user operates various types of slave robots in master-slave system, the fact that the dimensions of user does not match the dimensions of slave robot influence on the task performance. In particular, it is important to define analytically the effect of disparity between user and robot upper/forearm dimensions. In this paper, we describe the methods of arm posture representation and present the effect of ratio of upper/forearm length on the task performance. From the evaluation results, we can conclude that the effect on working task performance is small in case of disagreement between user and robot upper/forearm dimensions is lower than 20 percent.

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It is obvious that the human's arm and the shift are not mechanically and strongly connected. We grasp the shift knob by the compliant finger and through the soft skin. In this condition, the phase difference between the motion of arm and that of shift results from the move-allowance of the knob in the palm. By observing the palm over the transparent knob by using high speed camera, it has found that the skin rapidly deforms. In this study, it is hypothesized that the horizontal stretch of skin enhances the perception of the undulation.

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This paper presents the development of the modeling of human driving behavior based on mode segmentation. The transition between modes can be regarded as a decision making in the human behavior. In this paper, two kinds of decision are considered under a hierarchical structure. First one is a "intentional decision" which is caused by the change of intending task. Second one is a "reflective decision" which is made to accommodate with the change of situation. The former is modeled by the logistic regression model while the latter is modeled by the discrete/continuous hybrid system (HS) model. The usefulness is verified through application to the driving behavior on the express way.

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We built an acoustical telepresence robot named TeleHead. TeleHead has a user-like dummy head and is synchronized with the user's head movement in real time. The user-like dummy head improves sound localization accuracy. However, making the user-like dummy head for all users is not realistic from the viewpoint of engineering. Therefore, we make several kinds of simplified dummy head and make sure of their influence on sound localization. The results show that the user-like dummy head is the best dummy head for sound localization experiments. Ball-like dummy heads with user-like pinna make second-best results. When using a simple ball-like dummy head, participants cannot localize sound at all. It suggests that accurate dummy head improves sound localization accuracy. On the other hand, there is a possibility of simplification of dummy head at the point of sound localization for the users.

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Though the shift knob merely describes an arc trajectory, we can actually perceive the bumps and holes which are related to the tactile senses which are generally called "Setsudo-kan" and "Suikomi-kan." In this paper, the features about a size and a direction of its perceived surface are shown. Furthermore, we consider that the novel approach based on the neuroscience is essential for the haptic perception phenomena. In this paper, the brain function with respect to the shift feel was investigated by fMRI.

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The authors propose a method to use slenderness ratio of hand area as well as the contour information of a large number of hand shapes in advance in a database, for estimation of the human hand posture with wrist rotation by a single camera. The experimental results showed that the standard deviation of estimation error in all finger joints and speed are 13.22degrees and 9〜13fps respectively, and 13.22degrees and 1.3fps respectively without the ratio of hand area, suggesting that our method is effective.

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This study proposed a three-dimensional tactile sensor that enables to use a thin and soft elastic body without requiring any such processing as drawing of pattern on the surface or injection of pigment, etc., in the belief that this would enable to produce a wide dynamic range and a high resolution. We manufactured an optical type pressure sensor capable of irradiating a light in parallel to an elastic body, in such a way that the contour line may indicate the shape of the object material and, with the position of incidence of this light as clue, estimating the "contact position of the object material," "magnitude of the force," and "angle of incidence of the force." The estimation experiment showed that the output of the tactile sensor exhibits the same accuracy as that of a conventional hard and heavy sensor.

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This paper deals with the path planning of human digits in grasping a cylindrical object with the thumb and index finger. The trajectory of the thumb from initial position to the target could be divided into three patterns, a convex, double convexes, and non-convex type line. Moreover, the digit of thumb approached to the cylindrical object along to a tangential line with respect to the lateral of the object. Based on the obtained characteristics, the trajectory of thumb was approximated by the Bezier curve. As a result, it could be found that the distinctive patterns could be adequately expressed by the Three-order Bezier curve.

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In this paper, three-dimensional caging by a multifingered hand (3D multifingered caging) is studied. Caging is a method to constrain an object in which robot bodies surround the object and make it inescapable from the "cage" composed of the robot bodies. In 3D multifingered caging, position-controlled robot hands can manipulate objects, and force control is not necessary. Furthermore, even a robot hand with low degrees of freedom can constrain an object to manipulate. We formulate caging problems and derive sufficient conditions. In addition, we propose a method to plan robot motion with the sufficient conditions.

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It is well known that the DIP and PIP joints of the index finger move connectedly. The anatomical structure is considered to contribute to dexterous handling of an object. This paper treats a graspless manipulation of an object on a plane with an under-actuated tendon-driven robotic finger, which realizes the anatomical characteristics of the index finger. Some simulation is executed to confirm the role of the anatomical characteristics in the manipulation task.

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This paper considers control design of grasping and manipulation systems by multi-fingered robot hands based on the distance between the centers of gravity for the fingertips and the object. In the control design of the systems, controllers are usually designed for the variables with respect to the motion of the object and the internal force. However, it can not handle the approching/releasing tasks directly since it does not have the variables with respect to the distance between the fingertips and the object. In this paper, we propose a control design method for the grasping and manipulation system by the two fingered robot hand based on the distance between the centers of gravity for the fingertips and the object. Since the controller has the variables with respect to the distance between the centers of gravity for the fingertips and the object as well as the motion of the object and the internal force, it can handle the approaching/releasing tasks directly as well as grasping/manipulation tasks. A numerical example is shown to prove efficiency of the proposed method.

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We have been trying to develop an Assistive MObile robot System (AMOS). The aim of AMOS is to replace only simple assistive work that is to transport the daily use objects in a designated indoor location to reduce the burden of the care taker. In the system, at first an operator gives a command to the system what to bring, and then mobile unit approaches to an object, pick up and relocate the object semi autonomously. In this paper, we proposed a method using Reinforcement Learning to acquire grasp planning to pick up a daily life object. We assumed that pose and Voxel data of the object are estimated previously by vision components. And then state space is compressed to reduce calculation time, and the calculation is performed in off-line. Afterwards we performed on-line experiments.

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This paper analyzes grasp stability of two objects in three dimensions. To accomplish tasks efficiently, multiple objects are grasped and manipulated by a robot hand. In order to design stable grasp, grasp stability of multiple objects is quantitatively evaluated. Local shape of the objects at contact point is approximated by ellipsoid. Independent parameters of position displacement of the objects are provided and then position displacement of the fingers is derived. The grasp stability is evaluated from the viewpoint of the potential energy method.

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In this paper, we discuss grasping method for considering friction or softness of the object for multi-fingered robot hands. Though the grasp of the object with a little friction or the soft (deformed) object in general are complex and difficult, we consider them applying the grasping method of Gravity Compensation Force and Binding Force. We also propose Mass-Spring-Damper Lattice as a soft (deformed) object to polish the grasping method.

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It is difficult to plan a Multi Fingered Hand, because Multi Fingered Hand have many joint and many degree of freedom. We try out teaching and playback method by Restriction Type Data Glove. It has the same form and the same structure as Multi Fingered hand. This method is easy to manipulate some object by Multi Fingered Hand. Grasping is a popular manipulation. Compliance control realize grasping object. We experiment the teaching and playback method to grasp rubber ball and circle type connector.

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A therapist makes rehabilitation program for a patient to help him recover and mitigate his lost abilities. This paper proposes a hand tele-rehabilitation system. The system consists of a hand rehabilitation support system for the patient and an anthropomorphic robot hand for the therapist. The therapist applies the force to the robot hand. The force transmits to the patient using the rehabilitation support system. The effectiveness of the proposed system is demonstrated experimentally.

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This paper illustrates the relationship between the knotting process and robot hand skills. To extract a necessary hand skill for knotting, the knotting motion by human is analyzed. As a result, loop production, rope permutation, and rope pulling are extracted. Moreover, taking the handling of both ends of a rope into account, rope moving is added. Then, the characteristics of these skills are clarified from viewpoint of the intersection description. Based on the analysis of knot and the characteristics of robot hand skill, the knotting process is described. Finally, the experimental results are shown by using a high-speed multifingered hand system.

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The paper presents dynamic unfolding of fabrics by pinching slip motion. By keeping the textile in contact with robot fingertips, the dynamic unfolding is done successfully in horizontal direction. The success rate depends on fingertips shape. The grasping force is important for dynamic unfolding of textile by pinching slip motion. We simulate the contact force between fingertips and the fabric. Here, we assume that the contact force is described by contact between fluid and an obstacle in duct. We confirm validity of the experimental results using computational fluid dynamics.

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In this research, the surface electromyogram (surface EMG) and the pinching force when pinching an object were simultaneously measured for quantification of sensory evaluation. Cylinders with the length of 20, 40, 60, 80 and 100 [mm] and weight of 300 and 600 [g] were used for the experiment. Experimental results show that subjects feel comfortable to pinch the cylinder when the length of cylinder was 60 [mm]. The pinching force became the smallest and both of EMGs of adductor pollicis muscle and flexor digitorum superficialis muscle became small.

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This paper addresses characteristics of clothes in slipping operation, and a robot hand that can operate the task. Robot hand operation have been emphasis on pick-and-place, rolling and so on. However slipping operation is not noticed, and operation procedure in flexible objects have not been established. So, we research in slipping operation on clothes. For that purpose, we turned out a robot hand that has potential for working the operation. In this paper, a control approach, hand shape and feature included. Finally, characteristics of clothes are verified by pressure sensor.

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In order to achieve a skillful handling like a human hand, it is necessary that a hand has a capability to manipulate tools. One important problem of tool handling with a multifingered hand is that relative positions among a robot hand, a tool and a handled object change during the handling. For this reason, it is necessary to measure the relative positions in realtime, and to control a hand so as to cancel the changes. In our research, we have resolved this problem by using a high speed visual servoing. In this paper, as an example, a tweezers is handled by a multifingered hand. A new method to control tools and an experiment result are shown.

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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 tele-operating universal robot hand which has the same capability as human hand. To realize dexterous manipirlation task with robot hand, force and tactile infomation are indispensable. So we develop a robot hand tele-operation system which displays force infomation of universal robot hand using haptic interface, and shows tactile infomation on the computer screen. In this paper, we verify effects of force and tactile feedback in robot hand tele-operation through the universal robot hand tele-operation experiment.

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A multifingered robot hand can dexterously change a position and orientation of an object by regrasping an object. This paper proposes a strategy of a regrasping operation by three soft-fingered robot hand. The regrasping operation is realized by combining five basic motions. An digital camera system and ARToolKit library are used to measure the position and orientation of an object. To verify the capability of the proposed strategy, regrasping experiments by using three objects with different shape were conducted. Experimental results showed its effectiveness and reasonable accuracy.

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In this paper, a task measurement system for teaching-playback using haptic devices in a virtual reality environment is presented. The system measures the trajectories and forces of an operator's fingers during the task of pulling and putting a ring. Then, the measured data is suitably converted for playing back by a robot manipulator. We conducted experiments in the following conversion method : resultant force of the measured force of the operator's fingers as a target force of the manipulator. The experimental results showed its effectiveness and feasibility.

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This paper describes a explore motion of a robot finger using force information at the fingertip. The explore motion can detect a useful information to handle a deformable object or stacked objects. As an example of task which contains explore motion, we exam a towel picking with a robot hand from a pile of towels while exploring a hollow between towels using force information.

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Through using the master slave control systems with the network for the multi-finger hand, the experimental operations for the delicate works have been evaluated to perform remotely them. There were accomplished the kind of efforts for the device to convert the feed back forces to the operator.

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In this paper, the shapes of grasping objects are categorized based on grasping configurations of a robot hand that are applicable to the objects. Grasping configurations vary depending on the shape and mechanism of robot hand. We utilize a parallel two-fingered gripper as a general robot hand and determined seven kinds of primitives for modeling and abstracting grasping objects. In addition, the configurations of robot hand are parameterized for each primitive shape.

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We are searching for hobby robot related business - The educational robot industry has commenced in Nagano. We are introducing this product into the current market as well as presenting it for future prospects.Recently, robot kits for educational purposes and small humanoid robot kits for hobbies have become popular nationwide, particularly in urban areas.Now, robot education related events using the same kits are being held in Nagano also.

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The autoclave processing by which CFRP are being manufacturing for various industrial areas and the other out of autoclave processing are introduced and discussed.

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This paper describes optimal control for speed up Mechatoronic GARABO. GARABO is spinning machine that was developed at Nagano prefecture in the Meiji era. For control of Mechatoronic GARABO, we need to detect a yarn tension, because a yarn thickness has a relationship with a yarn tension. However, tension sensor has bad effects on yarn spinning. Therefore, we don't use tension sensor. Instead of it, we estimate a yarn tension using a disturbance observer. A mathematical model of Mechatoronic GARABO is made up of the system considers disturbance. We define what a yarn tension is a part of disturbance. We can take High speed control of Mechatoronic GARABO based Estimated tension control by a Disturbance Observer

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Motion sensing technologies are continuously having developed for analyzing or controlling the actual dynamic robotic motions, which are getting quicker and more complex. In this paper, a new skew matrix operation shall be introduced to describe 3D dynamic high speed rotation. With this technology in combination with six-axis motion sensor, a tiny wireless motion capture system will be realized soon.

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The final goal of this research is to develop functional rubber structures such as friction free rubber, adherent rubber, and shock/ noise absorption rubber, which will work as a flexible rubber robot body, a soft robot skin and a sole of foot. This paper reports the first step of this research on a micro rubber structure realizing multi-legged passive walking, which shows a great potential of realizing friction free or self walking rubber with micro rubber legs. A prototype of the micro rubber structure with many passive legs are designed, fabricated, and tested. The rubber successfully realizes passive walking on a sloping road.

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The aim of our research is walking pattern generation for a humanoid robot based on the Passive Dynamic Walk (PDW) concept. The stability of the walking pattern is of main concern. It is well known that stable walk is possible, provided the system parameters and the initial conditions are chosen carefully. So far, no explicit relation between initial conditions and stability are known. Therefore, the conditions are usually set empirically. But this is feasible only for simple models. In this work, we show how a stable walking pattern for a multilink (four-link) planar model can be generated via a simple two-link PDW model. The walking pattern is then realized via the computed torque method. Results are demonstrated based on data from simulations.

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This paper describes passive dynamic based walking for humanoid robot that has multiple degrees of freedom joints and an upper limb. To be capable of passive dynamic walking in level ground, we introduce the passive dynamic walking approach to our motion control method, and applying sinusoidal waves to emerge the walking motion on the biped robot model with upper limb. In addition, to reduce the collision of the foot and the tread of the robot when the swing leg changed places into the stance leg, the stance leg was given the rolling effect that was indispensable to passive dynamic walking by giving the curvature in the direction of the pitch and the roll on the soles. As a result, it is shown that the humanoid robot could walk with smooth oscillating and swing movement, and steadily in level ground.

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Since most of traditional biped walkers based on Passive Dynamic Walking (PDW) have arc feet and locked ankle joint, they cannot realize multimodal locomotion except walking (e.g. keeping standing posture, running). In this paper, we consider how we can substitute the flat feet with the arc feet. We hypothesize that the arc feet correspond to a circular Roll Over Shape (ROS), which is a shape of trajectory of center of pressure in human walking. We found that this circular ROS was generated by ankle joint driven by flexible muscles antagonistically. Measuring ROS with various tensions of muscles and equilibrium positions of ankle joint, we investigate the relationship between ROS and walking behavior.

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In this paper we propose a novel mechanism that enables the active/passive hybrid walking (A/PH walking). The mechanism is composed of a planetary gear system combined with a four-bar linkage joint We also propose a self-energized driving system, in which some pneumatic energy restored during a stance phase is utilized for the supplementary driving the knee joint during the subsequent swing phase. We call "self-energized active/passive hybrid walking" for this type of walking. This paper presents the mechanism of Robot Tokai-Robo-Habilis2 that embodies self-energized A/PH walking.

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Harata et al. have applied a parametric excitation method to a kneed biped robot with semicircular feet and have shown that the robot can walk sustainably with only knee actuators. A swing-leg of a kneed biped robot has similar mechanism to an acrobot, and most acrobots are controlled in inverse direction like ornithoid walking. This suggests that the inverse bending a knee restores more the mechanical energy than forward bending, and hence, ornithoid walking is more efficient. In the current work, we first compare the forward bending to the inverse bending for a double pendulum, and show that mechanical energy of the inverse bending like ornitoid walking increases more than that of the forward bending like human walking by numerical simulation. Then, we propose a parametric excitation based ornithoid gait generation for a kneed biped robot, and show that it can walk sustainably by numerical simulation.

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Ballistic walking is an approach for generating energy-efficient dynamic bipedal gaits. This paper formulates a method for generating ballistic gait under a constraint on the restored mechanical energy, and discusses the optimality of mechanical energy restoration based on the gait efficiency. We introduce a planar fully-actuated biped robot for the ballistic walking model. The simulation results show that impulsive actuation cases give the maximum walking speed, and a symmetric gait is automatically generated only by the ankle-joint actuation which can be reproduced as a kicking force by the rear leg. We discuss the symmetric gait generation mechanism from the angular momentum point of view.

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This paper proposes a novel method for generating efficient dynamic bipedal gait imitating the property of virtual passive dynamic walking. The control input in this method can be synthesized without including any singularities, and generates constant-like torque. A simple underactuated biped robot with an upper body incorporating a bisecting hip mechanism is introduced for the simulation model. We also theoretically investigate what effect the upper body had on the robot's driving mechanism, and show that it accelerates or disrupts the natural forward-swinging motion of the swing leg. Numerical simulations prove the effect, and show that the generated gaits exhibit period-doubling bifurcation.

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In this paper, first, we demonstrate the mechanisms of knee extension of stance leg in passive walking, and show the important role of the circular arc foot. Secondly, we demonstrate the influence of foot on the knee motion of swing leg. Finally, we derive the desired foot shape of passive walker, and demonstrate the validity of the foot by experiment.

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Passive biped running can exhibit a stable limit cycle only by interaction between machine and environment. In this paper, we study experimentally the passive running by rimless wheel with springs. We demonstrate the transition from walking to running, and show the interesting characteristics of running.

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In this paper, we consider effects of a feet in various convex shapes to performance of underactuated passive dynamic walking. First, a coordinate system to define the foot shape is introduced and the relationship between a foot parameter and an angle of the leg is derived. Secondly, the virtual ankle-joint torque is derived from the equation of motion. Finaly, we propose a method to design convex foot shapes that attain desired virtual ankle-joint torques and verify the accuracy of generated virtual ankle-joint torques by numerical simulation.

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The purpose of our paper is to design a three dimensional passive walker with sprung ankle and flat foot. Some 3D passive walkers have been developed with circular-arc or spherical foot with some passive devices to compensate yaw and roll motions. However, the foot has yaw motion because of low friction. We propose a flat foot with sprung ankle which stabilizes the lateral motion, and give a design method for the spring stiffness. Moreover, we prospect an effect of resonance between the swing leg and roll motion. Finally, we verify its effectiveness through experiments.

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The studies of 3D biped walkers driven by pneumatic artificial muscles have been capturing interest. However, these robots have not realized stable and long time walking. We suggest the feedback control method with swinging arms using a rate gyroscope for stabilizing behavior of the walking. First, we obtained ideal angle and angle rate of osillating motion in flontal plane by modeling the robot. Secound, we performed experiments using real robot with control of swinging arms and compared to the model. As a result, We verified that our control method was effective for stable walking.

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This paper reports some interesting results on our experimental case study of parametrically excited dynamic bipedal walking. We describe the detailed specifications of the final walking machine that has telescopic legs, semicircular feet, free hip-joint, and counterweights. The walker finally succeeded in sustaining stable dynamic walking on level ground in accordance with the principle of parametric excitation utilizing the effects of semicircular feet and counterweights. We also conducted numerical analysis to examine the change of gait descriptors with respect to the physical parameters, and the results show that the counterweights are effective for improvement of the gait efficiency.

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This paper proposes a foot shape design to enhance stability of passive dynamic walk, which constrains fall down phenomenon. We describe the possibility of introducing an energy-efficient controller onto this configuration, which controls the constraining effect by changing ankle angle. We propose a constrains foot shape applying to a biped robot to realize the stability of the passive dynamic walk.

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In our earlier work, high stability of passive walking can be achieved by the global stabilization principle of fixed point. However, the walker is small size. In this study, the grown-up size passive walker with knee joint is developed. Especially, the new mechanisms synchronizing the lower parts of outer leg and making the inter-leg angle at heel-strike constant are adopted. The shape of arc foot is adequately designed. Furthermore, a similarity for the human walking is investigated.

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In our earlier work, high stability of passive walking can be achieved by the global stabilization principle of fixed point. However, our passive walker can't control the walking direction. Thus, it takes the side trip over. In this paper, we propose the turning mechanism for walking direction control of passive walker. And, the variable slope mechanism is designed in order to investigate the adaptability or the robustness of passive walking.

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Death due to drowning accounts for about 30 % of unintentional injuries of 1 to 4 year infants in Japan. Development of an infant drowning prevention system is strongly required. This paper describes a newly developed system for preventing infant drowning at home. The developed system can measure the wave motion of water in the bathtub using an accelerometer, detect the abnormal wave motion, and give a warning to guardians with a radio communication. This paper discusses the optimum shape and size of the floating body of the preventive system and also presents a system for collecting motion data of bathtub water for long time in an ordinary home in order to conduct science of bathtub water in everyday life.

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In this study we investigated how the inner cushion influenced on the pressure distribution which was working at the head, the back and the buttock of the children when they sat on the child seat. This inner cushion was pre-produced to reproduce the pressure distribution between the children's body and their mothers' body when the children sat on their mother. From the result, the pressure distribution was quite similar when the children sat on the inner cushion in compare with that when the children sat on mothers' body. Therefore it is expected that the children feel 'held feeling by their mother' when children sit on the inner cushion.

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