To perform service tasks effectively, service robots must be able to handle not only low-level sensory-motor data, but also high-level semantic information. These data and information are bi-directionally linked, where low-level data is passed up and high-level information is passed down in semantic relationships and hierarchy. In this paper, these data and information are described as robot knowledge and associated with each other to integrate them into unified robot knowledge for service robots. Experimental results that demonstrate the advantages of using the proposed knowledge framework are also presented.

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In this paper, we introduce the human search and identification in the diverse environment without human operation or intervention. A supervisory control system is developed to search and identify a specific enrolled person in an undiscovered room under a wide variety of conditions such as many different illumination conditions, human poses, distances, and indoor configurations. We also consider a substantial exploration with the detector for human evidences that makes path planning suitable for center position of the human localization data. To validate our approach, we integrate our functional components on the intelligent robot software architecture of the CIROS platform and demonstrate the challenging robot mission successfully in the 2009 Grand Challenge Contest.

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We applied phantom sensation and sensory saltation to generate spatial and directional information using a hand-held device providing vibrotactile cues, T-hive. A sphere-shape is applied to the handle of the T-Hive for comfortable gripping, and the input part can provide six degrees of freedom of motion for the handle. To maintain isolation among vibrotactile actuators, the surface of the sphere is divided into several pieces. Each vibrating module consists of a vibration motor, a section of sphere surface, and a vibration isolator. As an evaluation of the developed device, two experiments were conducted to test whether phantom sensation is applicable to the entire hand uniformly. Our results show that the phantom sensation occurs whole hand uniformly. Also, spatial and directional information is useful for displaying intuitive information for object control with vibrotactile feedback.

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This paper presents a comparative study on three different force reflection methods in the time-delayed rate-mode bilateral teleoperation of remote vehicles. The first force reflection method is to directly apply an external collision force to a remote vehicle. In the second and third force reflection methods, the reflected force is calculated in proportional to the velocity errors between commanded and actual velocities of a remote vehicle in the master site and the slave site, respectively. For the stable teleoperation, the energy-bounding algorithm is applied to three methods due to instability when time delays exist in bilateral teleoperation. Three different force feedback methods are compared through experiments in the existence of time delays.

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Recently, haptic feedback has been an issue in mobile devices with a touch screen. The haptic feedback plays a role in generating button sensation on the touch screen. For the haptic feedback, vibration motors have been widely used, because they are small enough to be equipped into the mobile devices. However, commercial vibration motor is not able to create various haptic sensations. For the generation of a wide variety of tactile sensations, this paper proposes a smart actuator with actuating and sensing function. This actuator is composed of a solenoid, a permanent magnet, and an elastic beam covered with piezoelectric material. When electric cur rent is applied into the solenoid, the electromagnetic force by solenoid bends the elastic beam covered with piezoelectric material. This mechanism causes the direct piezoelectric effect of the piezoelectric material, and the electric signal is created from the piezoelectric material. The stroke of the proposed smart actuator can be estimated from the electric signal. The estimated stroke is used as a signal for feedback control. By feedback control using electric signal from the smart actuator, unwanted aftershocks of vibration can be reduced. The vibration signal without aftershocks conveys more crispy sensation to users, and it can generate various haptic patterns.

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In this paper, we investigate the relationship between the performance of telerobotic systems and the two independent time-delay on different modality, which are haptic and video. Especially, we try to find some performance improvement when the amount of delay of haptic and video is synchronized. Experiments were conducted with 10 subjects by scanning the amount of video and haptic delay independently. It is rather interesting to note that the teleoperation performance was not that sensitive to video delay, and the synchronized video and haptic delay doesn't show better performance than the case when haptic delay is lower than video delay.

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The mobile haptic interface is a novel solution for providing haptic sensations in a large virtual environment where a user can walk around. The feasibility of mobile haptic interface has been demonstrated by several research groups, but a number of challenging issues still remain in order to fully integrate a mobile haptic interface into advanced large visual displays. This paper presents a review on the current research status on mobile haptic interfaces and related engineering and evaluation problems. In addition, the design and performance of the mobile haptic interface being developed in the authors' laboratory are described briefly.

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In this paper, we present a bond graph representation for deformable and fluid objects. The bond graph model contributes 1. a seamless coupling between deformable particles by mean of the bidirectional power connection (effort× flow), 2. a unified modeling of a wide range of materials in the energy domain. Using bond graphs, we first define a 1D particle model for elastic and plastic deformation. Next it is extended to 2D and 3D deformable models. Finally, the bond graph model of deformation is simulated and animated.

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Chameleons have developed a specialized ballistic tongue which elongates twice their body length at speeds larger than 3.5 m.s^<-1> and accelerations 350 m.s^<-2>. Our project studies and mimics the mechanisms of the tongue of the chameleon in order to develop new technologies for manipulators. A first experimental set-up performs remote catching at a speed of 3.5 m.s^<-1>. Its acceleration reaches more than 900 m.s^<-2> and it elongates seven times.

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Antenna Hair-type Object for Generating Empathy (AHOGE) is proposed as an impressive component for helping existing Robot Technology (RT) and IT systems, where AHOGE influence human with mentality expressive motions based on posture element on nonverbal communications. The proposed mentality expressive motions for AHOGE are defined based on a pleasure-arousal plane. AHOGE will be applied to communication robots and Internet appliance which work in living environment, and then encourages effective assistances and close communication between human and RT&IT systems.

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In this paper, we propose a rubber-reinforced serial chain of torsion springs for an impulse force generator based on snap-through buckling of closed elastica. The distinguished feature of the proposed device is to utilize an elastic energy of rubbers for generating impulse force. Utilizing an elastic energy of rubbers, its weight reduction of conventional ratio 11[%] is realized with maintaining its high elasticity and flexibility. The proposed device can generate the maximum momentum 14[Ns] with only the required maximum driving torque 15[Nm]. The values shows that the maximum momentum per unit of the maximum driving torque of the device is about 1.2 times as large as the impulse force generator using conventional one.

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An idea of multi-leg system for aerial vehicles is proposed. It is a novel alternative of conventional landing gear and realizes adaptation to undulated terrain, shock absorption, gripping the surface of the ground, and support of its body after landing. Concept of the multileg system, mechanical design for shock absorption, simulation and experimental results are shown.

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In this paper, a novel omnidirectional vehicle with anisotropic friction wheels is presented. The proposed wheel has a series of bendable "nodes" on its circumference, each of which is made of two materials with differing friction properties: one material exhibits high friction, and the other exhibits low friction. The high friction section of the node generates a high traction force, while the low friction section enables the wheel to passively slide. The wheels are arranged such that the robot wheel exhibits high traction in its driving direction (much like a conventional tire), but low traction when sliding laterally. Due to this "anisotropic friction" property, the proposed wheel enables a vehicle to realize omnidirectional motion (i.e. the vehicle can move any direction within the plane-forward, back, or laterally). While many other omnidirectional wheel drives exist, the proposed wheel is simpler than any other existing design because the wheel is composed of a single, moldable element. This paper summarizes the design of the proposed wheel and presents a comparison between a small omnidirectional vehicle that uses the proposed wheel and an omnidirectional vehicle that uses conventional wheels.

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In recent years, a large number of studies have focused on micro-robots. Moreover, yearly contests have been held in order to develop micro-robot technologies. As a result of these activities, various types of micro-robot have been proposed, including motor-type, piezoelectric-element-type, and electromagnet-type micro-robots. The present study considers a moving mechanism of and a control method for an electro-magnet-type micro-robot that can not only run in a straight line but can also turn using only one electromagnet by adjusting the directions of permanent magnets installed in the robot and the input voltage applied to the electromagnet. In the present paper, the straight running of the micro-robot is mathematically modeled, and the characteristics of the motion of the micro-robot running straight on a horizontal plane and on an inclined plane are investigated through a number of simulations experiments.

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Movable structures can change their shape because each of the components are connected by hinges. Origami is a movable structure that can the freely relocate the crease as hinge, and changes shape. However, there have been no rigid body structures that have origami-like characteristics, since there has been no mechanism that can relocate hinges. So we have designed HDRM (Hinge Double Relocation Mechanism) which can relocate hinges, and have constructed movable structures by combining the HDRM. HDRM has been invented by adapting the mentioned requirement. And from making actual machine, it was confirmed that the constructed movable structures can change into various shapes by changing structural fabric.

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In this paper, we first clarify the notion of redundancy in general product design concluding three types of redundancy. We then propose a new principle to balancing of mechanisms, which is called redundant servo motor (RSM). The RSM approach stems from the very basic concept of redundancy in system design, recognizes the redundancy of the servomotor in mechanism systems, and makes use of this redundancy to balancing of mechanisms. Since the RSM principle proposed in this paper may look similar to several proposals in the literature, which utilize the servo motor for balancing of mechanisms, this paper provides a critical comparison of the proposed RSM principle with the existing proposals. This comparison further enhances the promise of the proposed RSM principle and unifies the theory of redundancy for robotic mechanism design especially for dynamic balancing.

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In our research, we use GETA, Japanese traditional wooden-clogs. The simulator we developed can simulate human walking with GETA. The simulator employs Central Pattern Generator (CPG) for bipedal walking pattern generation. The CPG based walking pattern is one of the candidates for simulating human walking. The average Japanese body dimensions data are applied to the bipedal model so that human walking efficiency is evaluated on the simulator. The proposed simulator is compared with real human walking, by analyzing the swing leg trajectory and the data from the pressure sensor on the GETA. The data show the effectiveness of the simulator, and point out that efficiency of walking with GETA is better than normal walking without GETA.

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A laser tracking system is employed for measuring the robot arm's tip with high accuracy. The geometric parameters in the robot kinematic model are calibrated by minimizing errors between the measured positions and the predicted ones based on the model. The residual errors caused by non-geometric parameters are further reduced by using neural networks, realizing the high positioning accuracy of sub-millimeter order. To speed up the calibration process, the smaller number of measuring points is preferable. Optimal measuring points, which realize high positioning accuracy with small point number, are selected using genetic algorithm (GA).

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Reaction forces acting on the bucket of a wheel loader from a scooped rock pile are modeled for autonomous control of wheel loaders. First, the behavior of the rocks in the bucket is directly observed by using a mechanical simulator. Since it is revealed that the behaviors are different in the phases of scooping, the reaction forces models are assumed in each phase. Then, the reaction forces calculated by the assumed models are compared with the measured forces by a force sensor installed into the mechanical simulator. From the experimental results, the models are verified. By using the obtained model, efficient scooping algorithm is expected.

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Authors have been engaged in the research on the outdoor working robotics, and targeting the autonomous pile loading operation by a wheel loader in mining particularly. Authors developed a real sized autonomous wheel loader "Yamazumi-4," and succeeded the unmanned autonomous pile loading operation experimentally. The precise traveling control is necessary to repeat loading operations. The real sized construction machines like the wheel loader are difficult to control the travelling speed precisely. Authors adopted the path planning and path following control based on the odometer and succeeded to gain precise geometric shape of the path. This paper describes the path planning and path flowing control of the autonomous wheel loader.

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Automation of breaker operation in working front of an open-pit mine, where a hydraulic breaker is employed to break massive rocks down, is considered in this paper. A human operator of the breaker moves a rock to a proper place before the breaking operation by using tip of a chisel as an end effector of the breaker. This moving operation needs trained skill of human operator because of "one finger operation" and is very interesting task on a robotic viewpoint - this can be categorized in so called grasp-less manipulation. The present authors intend to realize automated handling of the rocks with one finger. Technical elements for this framework are recognition of rocks, manipulator motion planning and control. The authors set up an laboratory scaled down experimental environment and use small rocks with a robotic manipulator to show the potentials of implementation and realization of this task. This paper reports overviews of procedures for recognition by means of binocular stereo vision and for manipulator motion planning. The authors also refer to the one finger moving operations rocks by using a robotic manipulator for 30 times and their statistics.

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In this research, we developed ergonomic master manipulator of NOTES (Natural Orifice Translumenal Endoscopic Surgery) robot system and suggested ways to use biomechanical simulation program for designing ergonomic master. We suggested metabolic energy cost index as an index of tendency of fatigue and we suggested design factors which reduce user's fatigue. Furthermore, we developed biomechanical model for comparing the ergonomics of hand tools, like master controller for reducing time and money spending. In addition, we will compare simulation results with user emotional assessment result for justifying user's preference and convenience is related to metabolic energy cost index. By this research, ergonomic evaluation of hand tools can be done by simulation program without manufacturing and spending for time and money.

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The femoroacetabular impingement comes from the abnormal shape of acetrabulm and proximal femur. It is treated by resection of damaged soft tissue and shaping of bone to normal feature. Arthroscopic treatment of femoroacetabular impingement has many advantages, minimally incision, fast recovery, less pain. But, in some cases, revision is needed because of insufficient resection of damaged bone from miss understanding of surgical site. In this research, navigation for arthroscopic treatment of femoroacetabular impingement was developed. The characteristic feature of femur was used in surface registration. The er ror of registration was simulated

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Recently, commercial master-slave manipulators have been used for minimally invasive surgery. This study develops immersive user interface for simpler and more intuitive manipulation compared with existing robotic surgery systems, such as da Vinci system. By using a 3-DOF master console, the human operator is able to control Augmented Reality-based surgical images using a 6-DOF slave robot holding an endoscope under the constraint of fulcrum point. The efficiency of the Augmented Reality-based surgical images is demonstrated, and experimental results confirm the accuracy of the manipulator control related to constraints of fulcrum point.

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Natural orifice translumenal endoscopic surgery (NOTES) has been received much attention due to its scarless operation resulting in faster recovery and shorter hospital stays than traditional surgical intervention techniques. The instrument for NOTES which passes through a natural orifice and navigates inside of the body should be flexible to reduce damages to soft organs but sometimes stiff to enhance its maneuverability. Fewer efforts have been undertaken to achieve quantitative design parameters for development of the instrument. To address this issue, we designed an instrumentation consisting of strain gage based force sensors and motion tracking sensors attached to the distal of an endoscope to measure not only the interaction forces between the device and the organ but also angles of deflection and twist of the device. A series of in vivo experiments on a male mongrel were performed by inserting the instrumentation from mouth to stomach. The measured data of the angles and the forces could be used to quantitatively determine design parameters of the NOTES instrument that satisfy a trade-off between its flexibility and maneuverability.

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In this work a telepresence system was developed to investigate the negative effect of large time-delay in the communication particularly during incision process with a soft-body which is common to the medical teleoperation. For a telepresence system, time-delay decreases level of synchronization between hand movements and the contact force perception and accordingly presents an unrealistic telepresence experience to the operators. The experiments prove that the instability due to incorrect perception for the operators can cause severe damages to the test object, since the operators perform the incision depending on their force-feedback perception via a haptic device. In this work an incision force compensation algorithm based on real-time FEM simulation techniques and computer visualization of the incision mechanics is proposed to handle the corresponding instability problem. The algorithm substitutes the delayed force-feedback signal from the actual force sensor on the teleoperator end effector with one from simulation during incision; consequently the delayed force-feedback signal is compensated and the level of synchronization between hand movement and the incision force perception is improved. Therefore the telepresence system is maintained stable.

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We propose a non-invasive ultrasound theragnostic system that tracks movement in an affected area (kidney stones, in this study) by irradiating it with high-intensity focused ultrasound (HIFU). In this paper, the concept behind a novel medical support system that integrates therapy and diagnostics (theragnostics), is illustrated. The required functions for the proposed system are discussed and an overview of the constructed system configuration is illustrated. Problems of stone motion tracking by ultrasonography are described. To overcome with this problem, we should take 2 approaches. The first approach is to minimize the servoing error to enhance both the efficiency of the therapy and the safety of the patient. The second approach is to reduce the effect of the servoing error. Concerning the first approach, we showed 2 solutions. One is robust detection of the stone position by shape information. Another is the controller that compensates for periodic motion of the affected area. Concerning the second approach, we propse a solution to control HIFU irradiation power in accordance with the servoing error, mainly to enhance the safety of the patient.

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This paper presents a design of a pedal actuating mechanism for a joystick car drive system. To realize pedal control system by electric power, a pedal actuating mechanism with a DC motor is developed. A single DC motor actuates a gas pedal and a brake pedal by alternating the drive shaft rotation. The movement of the DC motor is controlled by a joystick operated by a car driver. This system is developed for handicapped persons to drive a car by themselves without any helps by other people. The joystick operation in back and forth direction controls acceleration or deceleration of a car. Thus Therefore a person, who has disabilities in legs together with some disabilities such as no enough force nor move their arms in wide area, can drive a car by oneself. To reinforce the safety of a car in case of system fault, an emergency brake system is also developed which is actuated by air pressure. Therefore a car can be stopped by manual operation in any case. A pedal actuating mechanism is driven by an electric DC motor which is controlled by a microcomputer system. A pedal position is PID controlled by feedback control to track the reference angle given by a joystick. The prototype mechanism is mounted on a real van. Additionally, the developed van equips with a lift on the back and wheelchair user can access to the drivers position with propelling a wheelchair in side of a van. The developed joystick controlled van is tested on a private road to test the possibilities of proposed joystick car drive system.

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Essential tremor is the most common of all involuntary movements. Many patients with upper limb tremor have serious difficulties performing daily activities. We developed a myoelectric controlled exoskeletal robot to suppress tremor. In this paper, we focus on developing a signal processing method to extract voluntary movement from a myoelectric in which the voluntary movement and tremor were mixed. First, a low-pass filter (LPF) and neural network (NN) were used to recognize the tremor patient's movement. Using these techniques, it was difficult to recognize the movement accurately, because the myoelectric signal of the tremor patient periodically oscillated. Then, short-time Fourier transformation (STFT) and NN were used to recognize the movement. This method was more suitable than LPF and NN. However, the recognition timing at the start of the movement was late. Finally, a hybrid algorithm of using both short and long windows' STFTs, which is a kind of "mixture of experts", was proposed and developed. With this type of signal processing, elbow flexion was accurately recognized without the time delay in starting the movement.

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Abstract: Body weight supported (BWS) gait rehabilitation was introduced in year 1987. This method provides a safe environment for gait rehabilitation. However, the trade off of this method is the restriction of pelvic motion, restriction of body weight shifting, non-optimized weight bearing on lower limb, and the lack of interaction between patient and the system. A robotic mechanism is designed to provide natural pelvic motion, with capability of active body weight support. Body weight support control strategy for the robotic mechanism is introduced in this paper, which aims to address the issues faced in conventional BWS apparatus. The control strategy allows the motion of the patient to deviate from the desired trajectory, allowing more active participation of the patient. BWS force will be increased in accordance to the extent of the deviantion between the patient's trajectory and desired trajectory. Experimental setup is built to verify the robustness and response of the proposed controller. The experimental results show that the control strategy is able to achieve the objective of this wor k. The details of the experiments and results are presented at the end of this paper.

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In this paper, a new master-slave system for upper limb rehabilitation is proposed. Haptic device (PHANTOM Omni) is used as master robot and the slave robot has been designed to be portable and wearable. It is potential to be used in passive and active training which are prevailing approaches in upper limb rehabilitation and it is also suitable in home-rehabilitation through therapist's teleoperation. We describe the mechanical design of elbow joint module, force model and some preliminary results of passive experiment.

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The purpose of this study is to develop a pneumatic artificial rubber muscle which has a high contractile rate in order to realize a required performance for a power assist device. The developed rubber muscle is constructed with two nylon bands and an expansion unit, which is put between nylon bands. The generated force from the expansion unit is converted to a contraction force by the nylon band. This rubber muscle can be realized the high contractile rate. In this paper, the structure and the characteristics of the developed rubber muscle are described, and then the applications of this muscle are discussed.

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The shutter unit using electromagnet for digital still cameras/video cameras require to minimize the device size, maximize the shutter speed and actuator responsibility, and minimize the power consumption. In this paper , the problem on the past shutter unit will be discussed, and a new shutter unit will be proposed based on the simulation analysis. The evaluation with prototype shutter unit show the validity of the proposed shutter unit.

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Micro robotic colonoscope is a non-invasive intelligent examination instrument in recent years. Stable supporting is essential to the slide inner wall of gastro intestine. Double balloons method can be fixed on the colon wall efficiently and safely. This research aims at development of a novel miniature injection pump used to transfer air between the two balloons. The pump is composed of a linear actuator, an active valve, and a bellow. The linear actuator uses a DC motor, a gear reducer and a screw pair. The active valve shut off the inlet or outlet by squeezing the air tube. Two Shape Memory Alloy helixes actuate the valve's compression bar independently. The mechanism is designed in 3D software and a prototype is fabricated and assembled. it has 15 mm diameter, and 50 mm length, and 8.5 g weight. Some experiments are performed to measure the parameters. The endurable pressure ranges from 12 atms to 19 atms. The operating process indicates that the pump can work reliably. A model of the shut-off force is built to identify the characteristics of the pump. The results are consistent with the theoretical analysis. This pump uses a squeezing-shut-off mechanism, which is simple and reliable without air-tight.

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Photostrictive actuator, which can induce control actions under irradiation of high-energy lights, has been investigated for non-contact active vibration control of flexible structures in the last decade. A number of photostrictive actuator configurations with uniform control actions have been designed and evaluated. In this study, boundary conditions of a quad-photostrictive actuator design are altered so as to achieve continuous non-uniform control forces and control moments. Distribution of the actuator induced strains are defined by the variation method. A new skew-quad photostrictive actuator design which can induce multidegree of non-uniform control forces and moments is proposed. Photonic control of a simply supported cylindrical shell laminated with this skew-quad actuator is investigated. Control actions of center-located skewquad actuator are defined in the modal domain. Control actions with different surface coverage or actuator sizes are evaluated.

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Severe vibration of manipulator may cause accuracy loss or even damage. This paper presents the active vibration control characteristics of manipulator using laminated piezoelectric actuator. The mathematical model of the piezoelectric actuator stripe is presented. General formulas of modal control force and corresponding components are derived based on the converse piezoelectric effects and modal expansion method. The distributed modal control characteristics of piezoelectric actuator segments at different locations are investigated and compared, and the lateral vibrations of the manipulator are evaluated.

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