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In this paper, we deal with a remote robot system in which a user can operate an industrial robot with a force sensor at a remote location by using a haptic interface device. We apply a method using the wave filter together with the phase control filter which was previously proposed by the authors to the remote robot system for stabilization control. We also propose a method to enhance the haptic quality. By experiment, we demonstrate the effectiveness of the proposed method. We compare the proposed method with the conventional method quantitatively and clarify which domains the proposed method is applied to more effectively.

By experiment, this paper investigates the performance of kinematics stability of a master-slave manipulator system targeting for haptic-enabled remote control. Experiment of master-slave motion reflection was carried out, and the trajectories of both ends had been recorded by motion capture cameras. Experimental results illustrated inverse kinematics algorithm using Pieper's Solution can facilitate motion reflection with adequate stability and accuracy.

This paper considers tele-rehabilitation system by using the electrical stimulation based on the bilateral teleoperation for a human lower limb. The tele-rehabilitation means that a physical therapist rehabilitates a patient who is away from the physical therapist. When the therapist cannot check the condition of the patient directly, the haptic interface is used to feel the condition by the haptic sense. And the therapist moves the patient's lower limb by using the electrical stimulation indirectly through the haptic interface. In this way, the system that both the therapist side and the patient side are controlled each other is called as the bilateral teleoperation. However, the time delays of the communication cause the instability for the bilateral teleoperation. First, the mathematical model of a human lower limb is considered by using the linearization, the phase-lead filter is designed. Next, the paddle system as a haptic interface is modeled, the feedback controller is proposed. The scattering transformations and wave filters are constructed. Finally, the proposed tele-rehabilitation system is verified with respect to the stabilization and the control performance in the simulation and the experiment. As a result, the stability is compensated, the position error between the paddle and human lower limb is small.

In this paper, system design and motion control of a nursing lift robot which runs on the ground is presented. This supporting lift robot provides a power assist function for transfer aid system with hoisting and lowering, and also an omnidirectional motion function, using DDSS (Differential Drive Steering System). Further, logic control to suppress limit cycle of lift at grounding is proposed. The effectiveness of the proposed robot has been demonstrated through a lot of experiments in the present research.

This paper considers a written communication system based on a multilateral teleoperation using robust control. First, a pen equipment as an interface of the written communication system is developed. By using the pen equipment, the proposed written communication system based on sharing haptic information is indicated. Next, the non-passive approach is applied to the written communication system. The control objectives obtained from the stability condition and control performance are given. Next, the robust controller design is considered, because the motor of the pen equipment is influenced by the another motor. The pen equipments are modeled as a mathematical equation by the experimental results. A robust controller is designed so as to satisfy the stability condition of the non-passive approach. In the simulation and the experiment, it is verified that the control objectives are satisfied. Writing a character is demonstrated between two clients by using the written communication system in the experiment. As a result, two clients can recognize the character by sharing the haptic information.

In this paper, at first, a teleoperation robot systemwith haptic feedback for rehabilitation is presented. A teleoperation mechanism capable of providing force feedback by means of adjusting the system’s impedance is proposed. The stability of the teleoperation with haptic feedback via a time-delay communication environment is mathematically proved. The proposal operates theoretically with both passive and active assisted movement using teleoperation to rehabilitate of upper limb function. An EMG-moment arm model is proposed for assessing muscle strength. The performance of a two-joint link model using six muscles and a nonlinear relationship between EMG signals and muscle force is confirmed feasible in experiments with five subjects.

Holonomic omnidirectional mobile robot is useful with its high mobility in narrow or crowded place, and omnidirectional robot equipped with normal tires is desired for difference excess, vibration suppression and riding comfort. Caster-drive mechanism using normal tire has been developed to realize a holonomic omnidiredctional robot, however, there remains some problems. This paper presents effective systems to control the caster-drive wheels of omnidirectional mobile robot. Two kinds of Differential-Drive Steering System (DDSS) are proposed to improve the operation ratio of motors. One is using bevel pair gear and the other is using planetary gear to generate driving and steering torque effectively from two motors. Simulation results show the proposed system is effective for holonomic omnidirectional mobile robots.

In this paper, a novel measurement method to obtain three-dimensional shapes is proposed based on use of a bilateral vibration touch probe that outputs feedback voltage in accordance with its position. Measurement with high precision and rapid speed is realized by the probe. The probe has high rigidity with a simple structure. It can therefore move with high acceleration. In addition, a dimensional inspection can be performed by measuring several characteristic points, and a measurement of the characteristic points is used to shorten the measurement time, where it is assumed that rough positions of the characteristic points are provided. A new method using the probe of dimensional inspection is proposed, and the effects are shown based on experimental results.

In this paper, a power assisted wire suspension system which supports the setting of a mould is presented. The purpose of this system is to eliminate a worker's burden and to assist the skill for unskilled workers. This system measures the swing angle of the rope and the fluctuation of the mould's weight caused by operator's force, and it moves the AC servomotors of both the horizontal and vertical axes work in accordance with the detected swing angle and the force respectively. The effectiveness of this power assisted system is confirmed by experiments for setting of the mould.

In this paper, a power-assisted wheelchair to support helpers is presented. The model reference control system is proposed such that the wheelchair comfortably moves at the ideal speed with helper's weak force, and H infinity controller is implemented in order to highly maintain the control quality regardless of the disturbance such as the variation of a passenger's mass or the slope of the road. The effectiveness of the proposed system is validated through various experiments such as the comparison with the PI controller, change of patient, the up-and down-slope, and the rotary motion.

For improving the operability of an omni-directional wheelchair provided with a power assist system, the system must be able to adapt to the individual characteristics of the many different attendants that will use it. For achieving this purpose, an innovative human-interface using a touch panel that provides easy input and feedback information in real time of the operation of a power-assisted wheelchair was developed. The system was tested experimentally with many different attendants and the results show that in addition to providing a human friendly interface by using the touch panel system with a monitor, the system can successfully adapt to the particular habits of the attendants. Furthermore, control of the rotation center of the OMW is proposed by making use of the OMW's potential advantage and coordination transformation.

In this paper, a master-slave robot system involving haptic feedback and teleoperation for rehabilitation is presented. A teleoperation mechanism capable of force feedback by means of brake is proposed. The stability of the teleoperation system with haptic feedback via a time-delay communication environment is mathematically proved. Moreover, in order to reduce the packet transfer rate for data transmission, a deadband control approach is used. A new data reconstruction algorithm is proposed to improve the system's performance while maintaining the system's stability. This system allows passive assisted movement utilizing teleoperation for the rehabilitation of upper limb function.

In this paper, development of the force sense sharing network game using the websocket and physics engine is described. In this game, a game player can put a force on a haptic device placed at a remote location, and measured force is added to a physics engine which operates force interference calculations. At the same time, the physics engine sends back the resultant position to the haptic device in order to present the force sense to the game player. The websocket is adopted in order to realize the fast real-time two-way communications, which involves multilateral tele-control, and connect to unspecified large number of clients in the Internet. It is confirmed in the experiment using the network emulator that the position and force information coincide between the server and the client under a communication delay environment, and system is stabilized in multilateral tele-control.

In this paper, a power assisted system for an overhead crane is presented. This system is realized by measuring the swing angle of a crane and moving the trolley and girder in the desired direction. Therefore, operators can move a heavy object freely using only slight force. In this paper, two kinds of controllers are proposed. One is a PD controller that emulates the dynamics of object with damping and it moves the object in proportional velocity to the operating force in steady-state. Another is a PID controller that maintains the velocity of object continuously after operators cease the application of their force. Its dynamics, damping characteristics, steady-state and admissible condition of controller gain are discussed in regard to the respective controllers. This system is applied to an experimental overhead crane in the laboratory, and the effect of energy saved by the power assist is shown by measuring the heart rate of operator.

The purpose of this paper is to present the expert massage robot using a multi-fingered robot hand. First, the fingertip forces applied by an expert human therapist was measured using sheet distribution pressure sensors, and the obtained data was recorded in a computer. After the measurements were taken, the human expert's fingertip force was reproduced by teaching and playback method using the robot. Through simulation and experiments, the usefulness of the proposed control systems was demonstrated. Second, in order to advance the above teaching and playback control system, the present paper gives a modeling of human skin muscle through robot perception of impedance, and a control strategy using impedance control to implement adaptive control system, even if human condition is changed. The model validity is demonstrated via many experiments by using multi-fingered robot hand and human body. Based on robot perception of human muscle impedance, impedance control is proposed, and its effectiveness is shown via computer simulation study.

In this paper, the path planning considering rotary motion of load is presented for automous overhead crane. First, we give the condition of interference between a rectangular load and obstacles, and a movable area without interference is decided in the configuration space. Secondly, a secure path planning is derived by the potential method based on extended 3-dimensional diffusion equation considering rotary motion. Furthermore, the parameter of suppressing rotary motion in the extended diffusion equation is clarified, and its effect is demonstrated. Finally, Quadratic curved surface interpolation method is proposed to get the smooth path planning, and the effectiveness of the proposed method is demonstrated through simulation results.

In the aged society, it has become more important than in the past to develop technologies for human assist. In this paper, a power assist system for the attendant of an omni-directional transport wheelchair is developed. The applied force of the attendant is measured by a force sensor attached to handles of the wheelchair. The desired motion of the wheelchair is estimated from the output signal of the force sensor using fuzzy reasoning. Then, it is transmitted to four motors of the wheelchair to make it move toward desired direction. The effectiveness of the proposed method is examined by experiments.

In this paper, a master-slave robot system with haptic feedback, human sensing and teleoperation for rehabilitation of upper limb function is presented. The physician could adjust on-line the exercise based on the EMG signal of the patient and force feedback. Moreover, in the present teleoperating system, it is shown that the stability is guaranteed due to the passivity of the master arm's mechanism, in spite of the communication time delay.

Wheelchairs are the most common used device in order to allow elderly and handicapped people more independence and greater interaction in their communities. The purpose of this research is to control the motion of an Omnidirectional Mobile Wheelchair (OMW) while considering user's comfort. A human model is built for evaluating the proposed controller, considering that the human upper body consists of two rigid parts: head and torso. The proposed controller can not only control OMW fast and effectively but can also improve users’ comfort greatly by suppressing vibration caused mainly by inappropriate acceleration while driving.

An omni-directional wheelchair is highly maneuverable in narrow or crowded areas such as residences, offices and hospitals. However, with the increase in the degrees of freedom accompanying omni-directional wheelchairs, it has become more important than in the past to develop a smooth and vibrationless motion control system. In this paper, a novel motion control method for an omnidirectional wheelchair considering the suppression of vibration of both the wheelchair and the patient is proposed. In the proposed control system, the vibration of the wheelchair is suppressed by notching the frequency characteristics at the natural frequency of both the wheelchair and human's organs. The designed controller satisfies various control specifications such as settling time and stability by using feedback from only the wheelchair's position data. The effectiveness of the proposed system is evaluated by the output signal of a sensor attached to the wheelchair and by a descriptive inspection by several users.

Aiming to assist operators, our laboratory had proposed power assisted wire suspension system. A system to estimate the operating force based on ground reaction force and human behavior has been developed. However, it is necessary to measure the human behavior (position, velocity, and acceleration) of 17 points on the body with the conventional human dynamics model. Therefore, the system is extremely expensive and not practical, because of large number of sensors. In addition, fewer sensor units worsen the estimation accuracy of the operating force. In order to improve the estimation accuracy of the operating force, it is important to identify positions of center-of-gravity and masses of links. Thus, this paper presents the novel human dynamics model estimating the operating force and parameters using extended Kalman filter based on human behavior with only 6 sensor units and ground reaction force. Improvement of the estimation accuracy is confirmed by experiments.

This research is suggested a design method a tele-operation control for liquid container transfer by an overhead crane system that allows the operator to control the speed of the overhead crane freely and to feel the swing of the rod instinctively through the reaction force. In remote control, the information of the distant place is important. Particularly, feeling the reaction force for operation is important like watching the rod's movement with cameras. The proposed system in this research can be used via the internet and can be controlled from everywhere. For example, operating in a place such as the steel and the casting factory where is bad work environment due to a high temperature and mine dust, this tele-control system using the internet as its communication line can be useful, since it allows the operator to control the crane from a safer and good environment place. The usefulness of proposed system is demonstrated by an experiment.

Social communication based on visual and auditory has enabled communication. However, Internet communication based on haptic interface has not generally spread yet. This study will achieve that tens of thousands of people share the sense of force and enjoy the Internet games such as tug-of-war by stabilizing the whole system in spite of Internet communication delay. Our proposed method consists of the phase control filter and phase compensation filter. First, phase characteristics of the scattering matrix is derived, and it is proved that the combination of phase control filter and scattering matrix are passive. Second, the combination of phase compensator and mechanical model in the emulator are also passive. Thus, the closed loop system being non-passive system, in which input/output are force/position, can be stabilized. Finally, validation for our proposed system is demonstrated though some simulation.

In this paper, we propose algorithms of design for a motion path that is capable of strengthening specific muscles. By using the proposed algorithm, it is possible to design a motion path maximizing the activity of an agonist muscle and minimizing the activity of other muscles. EMG signal is measured during a trainig experiment and the degree of muscular revitalization is evaluated by the amplitude of EMG signal. Finally, the effectiveness of proposed approach is demonstrated through experiments.

This paper presents a tele-control system comprised of a robot hand/arm and an operator. In our system, the angle of the finger of the robot hand is controlled according to the angle of the operator's finger, and the position of the robot arm is controlled according to the position of the operator's arm. Simultaneously, the operator feels the environmental force as detected by the touch sensor attached to the robot hand, resulting in so-called bilateral master/slave control. To date, there have been a few studies of bilateral master/slave systems that use a multi-fingered humanoid robot hand in communication networks with delay caused by physical distance. The purpose of our study was to achieve tele-operation with bilateral master/slave control between the operator's hand/arm and the multi-fingered humanoid robot hand/arm using the Internet with delay caused by distance. For our experiment, the operator was in the USA, and the multi-fingered humanoid robot hand/arm and object were in Japan. Using our system, the operator could successfully grasp and move an object while he felt the reaction force from the object. This technology can applicable to tele-operation such as feeling the hardness and weight of the stone which exist in the moon, on the ground etc.

This paper presents a design method for a tele-operation controller for an overhead crane system that allows the operator to control the speed of the overhead crane freely and to feel the swing of the rod instinctively through the reaction force. Feeling the reaction force makes it easier for the operator to know about the swing of the rod than simply seeing the rod's movement through cameras. This system can be used via the internet and can be controlled from everywhere. For example, operating in a place such as a nuclear power plant, where it could be dangerous for humans to be in the case of an accident, this tele-control system using the internet as its communication line can be useful, since it allows the operator to control the crane from a safer place. The use of our system is demonstrated by an experiment run jointly by Toyohashi and Toyota.

Specific muscle training is expected to be used for efficient rehabilitation and care prevention. In this paper, we propose algorithms for designing a motion path capable of strengthening specific muscles. By using the proposed algorithms, it is possible to design a motion path maximizing the activity of an agonist muscle and minimizing that of other muscles. For training, the load is applied by using a 2-link arm. EMG signal is measured during a training experiment, and the degree of muscular revitalization is evaluated by the amplitude of EMG signal. Finally, the effectiveness of the proposed approach is demonstrated through experiments.

In this paper, a power-assisted attitude control system consisting of parallel wires is proposed. This system controls the attitude of an object, thus reducing the burden on the operator and allowing direct manipulation. In our previous research, a power-assisted control system for an overhead crane was proposed. Operators could move a heavy object freely in horizontal and vertical directions and adjust one-degree-of-freedom (1-DOF) attitude by inputting a slight force grasping the object directly, that meant the operator did not feel any sensors. Our newly proposed equipment consists of an overhead crane and two linear cylinders. A power-assisted 2-DOF attitude control algorithm that controls the length of the cylinders and hoisting motion of the crane synchronously is proposed, and the effectiveness of the system is demonstrated in some experiments.

This paper presents a tele-control system constructed by a robot hand/arm and operator. The angle of the robot hand is controlled by the angle of the operator's finger, and the operator feels the environmental force, as detected by the touch sensor of the robot hand, constituting so-called bilateral master/slave control. The position of the robot arm is controlled by the position of the operator's arm.So far, there has been little research using a multi-fingered humanoid robot hand in a network environment where communication delay exists. The purpose of our study is to achieve tele-operation between an operator's hand/arm and a multi-fingered humanoid robot hand/arm with delayed time. Therefore, this study constructs a system that can grasp and manipulate objects stably, despite the communication delay.In the experiments, the operator operates humanoid robot hand/arm of Toyohashi University of Technology from USA. The operator grasp and moves an object in Japan by operating the humanoid robot hand/arm. The staff in Japan gives the operation instruction to the operator in USA during experiment. The operator operates robot according to the voice. The experimental results show that this system can grasp and manipulate objects stably, despite the communication delay. In addition, the operator grasped the object using a multi-fingered humanoid robot hand/arm by master/slave control feeling fingertip force by tele-operation between USA and Japan.

This paper gives an advanced driving control system that considers sway suppression of a passenger's posture in an electrical wheelchair. We proposed a passenger model that considers the passenger's physical frame and seating condition. The passenger's seating condition is classified as upright, standard, or round-shouldered posture. The sway of a passenger with round-shouldered posture is smaller than that of a passenger with upright posture, and they can be represented by the proposed model. To suppress the sway of a wheelchair passenger's posture, the wheelchair driving pattern is optimized using the proposed passenger's posture model. The comfort of the passenger with respect to the proposed wheelchair driving is evaluated through experiments.

So far, a lot of lift walkers have developed to help patients. However, the use of the conventional lift walkers may change the walking posture and reduce curative effect. In this paper, the walk using the lift walker is analyzed and the method to support appropriate walk is suggested. First, the walk in accordance with graded weight is measured with 3D motion analysis system. Next, variation of velocity, step length, term, and each joint of walk are evaluated. Finally, the method which does not change the walking posture is proposed. As the result, it is clarified that the lift walkers obstruct the motion of hip, knee, and foot joint.

Our proposed power-assisted wire suspension system has three advantages. First, the structure is simple, and the cost is lower than that of other rigid systems, because the mechanism is based on an overhead crane. Second, it is easy to effect sequence control using this system because the sequence control is based on the velocity control. Finally, this system is expected to supply efficient conveyance by any operator, because operators can move heavy objects directly with two hands. In this study, we compared the effectiveness of the proposed power-assisted system that has sequence control with the conventional operation using buttons through experiments involving the measurement of the precision of the positioning and the work time needed to assemble objects.

In this paper, a teleoperation mechanism capable of providing force feedback by means of adjusting the system's impedance is proposed for a master-slave telerehabilitation robot system. The stability of the teleoperation with haptic feedback via a time-delay communication environment is mathematically proved. By using the proposed teleoperation mechanism, the telerehabilitation system can work theoretically with both passive assisted movement and active assisted movement for the rehabilitation of upper limb function. Experiments with single DOF master-slave robot system show the effectiveness of the proposed mechanism.

To improve the operability of a power-assist omnidirectional wheelchair driven by attendant, an improved neuro-fuzzy control system and an innovative human-interface using a touch panel was developed. The neuro-fuzzy controller was modified to improve the operability of diagonal motions. Moreover, the touch panel provides easy input and feedback information of the operation to adapt to the individual characteristics of different attendants in real time. The proposed system was tested experimentally with many attendants, and the experimental results show that the system can adapt successfully to the different tendencies of attendants.

This paper presents an advanced control system for a driving control system of an electrical wheelchair. The aim of the control system is to make possible a comfortable ride in the wheelchair. For this, a passenger model that uses a backrest in the wheelchair has been constructed and a driving pattern that suppresses a passenger’s posture behavior has been developed using optimization methods. Then, the quality of the ride while a passenger drives the wheelchair has been evaluated by a questionnaire and by measurements of emotional sweating. In comparison with the conventional driving pattern, the proposed driving pattern suppresses about half of the passenger’s previous posture behavior and improves the comfort of wheelchair driving.

This paper presents a tele-control system constructed from a multi-fingered robot hand and operator. The angle of the robot hand is controlled by the angle of the operator's finger, and the operator feels the environmental force, as detected by the robot hand, constituting so-called bilateral master/slave control. In the experiments, the operator grasped the object in spite of Round Trip Time (RTT) as Osec, 0.56sec, using a multi-fingered humanoid robot hand by master/slave control feeling fingertip force. However, with increases in the RTT, the operation became more difficult. We also analyzed the stability of the master site and the slave site by frequency characteristics. The results showed that this system was unstable. However, grasping by tele-control with a communication delay was demonstrated.

It is difficult for a novice rider to navigate an omni-directional wheelchair through a narrow space such an elevator door or a path along the wall because it is always necessary to keep in mind the width of the vehicle. Such navigation can produce stress in the operator. In those cases, a navigation guidance system that appeals to human's sensation of touch can be useful. In this paper, a novel navigation guidance system using a haptic feedback joystick is proposed for the omni-directional wheelchair. The present navigation guidance system adopts a force feedback joystick in order to induce the operator to evade obstacles.

This paper proposes an intelligent massage control system by using multi-fingered robot hand with hybrid impedance control, which is able to create the movement and the force of robot such as the human's massage. Therefore, the various massage points, such as the change of the stiffness of human skin muscle, can be controlled by using impedance control method. The hybrid impedance control is comprised of the two methods of the position-based and the force-based impedance control were applied. The position-based impedance control is used to control the lateral position of massage on the human skin muscle. On the other hand, the force-based impedance control is used to control the force of the vertical direction on human skin muscle. This paper also gives the identification of human skin muscle through robot perception of impedance to decide the parameter of impedance controller. The control strategy using impedance control to implement an adaptive control system is presented, when human condition is changed with soft and hard skin muscle. Effectiveness of massage control system by using multi- fingered robot hand with hybrid impedance control is demonstrator through actual massage experiments of pushing and rubbing motion.

This paper proposes an intelligent massage control system by using multi-fingered robot hand with hybrid impedance and force control, which is able to create the movement and force of robot to behave as similar as the human's massage. Therefore, the various massage points, such as the changing of hardness and softness of human skin muscle condition, can be appropriately controlled by using hybrid impedance and force control method. The impedance control is used to control the lateral position of massage on the human skin muscle. The perpendicular direction one, while force control is carried out for the vertical direction on human skin muscle. This paper also gives a modeling of human skin muscle through robot perception of impedance to decide the parameter of impedance controller. The control strategy using a hybrid impedance and force control to implement an adaptive control system is presented, when human condition is changed with soft and hard skin muscle. For the robot fingertip force, PI servo compensation is used together with impedance control. Based on using both impedance and PI servo compensation, the effectiveness of the massage position and force control is shown through actual massage motion experiments.

In this paper, a novel power assist system for the attendant of an omni-directional transport wheelchair is proposed. The input force of the attendant is measured using a force sensor attached to the handle of the wheelchair. The desired motion of the wheelchair is estimated from the output signal of the force sensor using fuzzy reasoning. Then, it is transmitted to four motors of the wheelchair to make it move toward the desired direction. The effectiveness of the proposed method is examined by simulations and experiments.

The present paper gives a haptic feedback control of a holonomic omni-directional mobile wheelchair (OMW) with a haptic joystick for the operation of disable people or elderly people considering not only the navigation task but also user's comfort and safety. In the present research a haptic joystick was designed and applied with being maneuverable for users and free of joystick's vibrations. If an obstacle is detected in the direction of movement, the impedance of the joystick in this direction is changed. Namely, the closer the obstacle is the bigger the impedance value becomes. By this function, users spontaneously understand that they are in risk of obstacle collision and then users can change the direction of movement, by their decision, in order to avoid it. Furthermore, for the command input by human joystick operation, velocity control of OMW is executed by means of frequency shaped control to achieve the comfort drive for users. The proposed approach is thought to be reasonable as a man-machine existing control system.

In the aged society, it has become more important than in the past to develop technologies for human assist. In this paper, a power assist system for the attendant of an omni-directional transport wheelchair is developed. The input force of the attendant is measured using a force sensor attached to the handle of the wheelchair. The desired motion of the wheelchair is estimated from the output signal of the force sensor using fuzzy reasoning. Then, it is transmitted to four motors of the wheelchair to make it move toward desired direction. The effectiveness of the proposed method is examined by experiments.

The purpose of This work is to describe the development of a safe, semi-automatic man-machine control system in which the automatic control of a machine is incorporated with manual instructions from an operator. First, a haptic joystick which can provide suggestive information to a crane operator via haptic feedback was developed. Second, operational support was provided to the joystick through the application of the impedance control and the gravity compensation. Third, restrictions on the crane's velocity were, imposed by haptic control. Finally, the validity of the proposed haptic control system which can easily and safely transfer a load to arbitrary positions without colliding with obstacles was demonstrated experimentally.

In this paper, riding comfort of an omnidirectional wheelchair (OMW) driven by joystick is studied for the case when OMW moves in X direction, Y direction, or in a slanting direction. In order to achieve the comfort driving specific spectrum elements such as natural frequency of OMW and discomfort frequency of human organs are suppressed. In order to evaluate the comfort, a human model which considers human upper body composed of two parts: torso and head, has been developed and used in order to test the effectiveness of the proposed approach. Experimental results of velocity control are shown.

This paper presents a massage motion control system comprised of position control and force control in a multi-fingered robot hand. By making use of an algorithm which converted the desired fingertip trajectory into the desired angle of links in each finger by means of inverse kinematics, the finger position control from the initial position of the multi-fingered robot hand to a target position of the objects for massage was achieved. Its controller was used until the robot hand contacted the objects for massage. After contact was made, the fingertip position control was switched to a force control position needed to apply pressure for the massage. The fingertip forces exerted by an expert human therapist was measured using sheet distribution pressure sensors, and the data obtained was recorded in a computer. After the measurements were taken, the human expert's fingertip force was reproduced by the robot hand. The fingertip force of the robot hand was controlled using feedback obtained with a 6-axis force sensor. To make the force of each fingertip of the four-fingered robot hand track to the fingertip force exerted by the expert human massage therapist, PI servo compensation and a Jacobian matrix were really applied for the human's shoulder. Through simulation and experiments, the usefulness of the proposed control systems was demonstrated.

An omni-directional wheelchair is highly maneuverable in narrow or crowded areas such as residences, offices and hospitals. However, with the increase in the degrees of freedom accompanying omni-directional wheelchairs, it has become more important than in the past to develop a smooth and vibrationless motion control system. This paper presents a novel motion control method for an omni-directional wheelchair considering the suppression of vibration of both the wheelchair and the user. In the proposed control system, the vibration of the wheelchair is suppressed by notching the frequency characteristics at the natural frequency of both the wheelchair and human's organs. The designed controller satisfies various control specifications such as settling time and stability by using feedback from only the wheelchair's position data. The effectiveness of the proposed system is evaluated by the output signal of a sensor attached to the wheelchair and by a descriptive inspection of several users.