In previous report, we have reported that 3 degrees of freedom precise mobile mechanism that is composed of three solenoid actuators and 4 "Moonie" piezoelectric actuators. The mechanism moves like an inchworm by an synchronization of an alternately fixing of two legs to a floor and vibrations of the piezoelectric actuators. However, this mechanism does not move precisely as designed because of ununiformity of the static forces among 6 legs and the floor. In this report, we have described newly-proposed frictional force control method based on the internal force feedback control of the 3 solenoid actuators with 6 pressure sensors attached to the 6 legs.

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Generally, low backlash mechanisms are required for robot joints to perform tasks accurately, so we are proposing a new concept of a low backlash reducer using precessing crown gears. We call it the crown reducer. The features of this reducer are low backlash, high reduction ratio and ease of downsizing which we believe will contribute to the design of small mechanisms such as finger joints of robot hands. This paper describes a improvement of input mechanism (press rotor) for increasing durability itself. Evaluations of the performance of a prototype reducer will be discussed.

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Since legged robot is expected to be suitable for activities in rough terrain, many studies have been focused on its motion control. In order to enhance the use of robot in human life and improve the movement speed, jumping is one of desired behaviors for robots. This study focus on the development of mechanical energy-efficient hopping robot with a spring leg and a drive control system. Applying the force to the spring leg at the robot's resonance frequency, the robot can jump by using compact actuators. In previous study, the algorithm using eccentric weight to make the robot to jump continuously have been shown. In this paper, the control method of the jump height is shown with the improved algorithm.

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Safety is important in the space where humans and robots coexist. Lightweight of robots is one way to achieve the essential safety for humans. To ensure safety, we make efforts to develop extremely lightweight soft actuators. So far, we have established design approach of a bending type soft actuator by utilizing plastic films with pleated structure. In addition, we verified that the actuator generates a helical twining movement by several oblique pleats. This paper indicates that the actuator can generate various helical shapes by changing two kinds of parameters which are folding angle and pleat pitch. Further, we experimentally developed the actuators and verified the helical shape.

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The purpose of this study is to investigate the properties of the shape memory alloy by using a fluorine-based inert liquid. We have made an SMA actuator having a cooling mechanism. We are also considering the application to the driving source of pediatric prosthetic hand power to the actuator. In this paper, we describe the development methods and prototype of the SMA actuator. Furthermore we explain experimental results of the basic characteristic. As the results, we confirmed that the fluorine-based inert liquid has a usefulness for the cooling of the SMA.

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An ultrasonic motor is generally composed of a vibrator and a rotor, and is driven by the frictional force between stator/rotor. Since the contact points on the stator draw elliptic trajectory, relative speed of the point against the rotor varies even when the rotor rotates with a constant speed. This may cause wear and a decrease in efficiency. This research proposes a novel method to reduce the relative speed variation to improve the efficiency of ultrasonic motors by superimposing harmonic vibration with driving vibration. Results of numerical calculation show that the efficiency may be improved by 27 % by the proposed method.

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Low cost "smart" servomotors widely used in robotics research present several control issues due to non-linearity at high torque and low performance controllers. Using publicly available physical simulation packages with PGS and Danztig solvers we can create very accurate faster than real-time models of a smart servomotor for use in control optimization. Simulation results are within 1.0 degree of the experimental results without external loading, and demonstrate identical non-linearity when the motor is driven above the torque limit.

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In this study, an ultrasonic motor for a solid-state high resolution nuclear magnetic resonance (NMR) spectrometer has been fabricated and evaluated. In solid-state NMR analysis, it is necessary to rotate samples at a high speed and a high preciseness. The motor are composed of non-magnetic materials. The motor consists of two sector shaped vibrators. The diameter and the height of a probe unit including a sample case and the motor are 31 mm and 50 mm. The unit was unaffected by the magnetic field. The rotation speed was 1200 rpm when the magnetic flux density was 9.4T. Additionally, we have successfully obtained a solid-state NMR analysis of glycine. From this result, the motor can be applied to sample rotation of solid state NMR spectrometer.

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A robot which runs under a human symbiotic environment needs to reduce the possibility of mechanical failures in collision. Most commercially available humanoid robots use actuators with gears, and they are damaged easily with a shock. Actuators, without gears for a drive division, using a polymer or the air pressure to resolve such problems have been developed so far. This paper focuses on the MR fluid that changes its apparent viscosity by a magnetic field and proposes a functional fluid linear actuator that transforms linear vibration one-way motion by controlling functional fluids. It shows the validity of the proposed functional fluid linear actuator so that we design and develop prototypes of the proposed actuator, design a controller for the actuator, and investigate the behavior of the actuator.

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We developed a linear actuator using ER gel to apply a human-coexistence robot, e.g. power assistance system or rehabilitation system. In this paper, we have treated a velocity control of the actuator referring to the to position and velocity response model. We have verified a vibration in the response of simple IP control system. Therefore, we introduce a disturbance observer to compensate the model error.

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In this study, a torsional transducer type ultrasonic motor which realizes the continuous rotation and the positioning of the angle in cryogenic temperature has been fabricated and evaluated. In the cryogenic temperature environment, the performance of the transducer falls. In order to drive the motor at cryogenic temperature, the torsional transducer is designed to generate the resonant stick-slip drive. The transducer can perform the resonant stick-slip drive by combining the first and the second vibration mode. The ultrasonic motor using the transducer was evaluated. The rotation speed and the starting torque are 111rpm and 0.75mNm at 4.5K. Moreover, a velocity control became possible in the low-speed range below 1.0rad/s by using a burst waveform.

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Press machine with a differential rotary to linear conversion mechanism was manufactured in order to evaluate the positioning performance of a punch. This differential rotary to linear conversion mechanism consisted of two rotary shafts, a rotation/translation shaft, three spur gears and a connecting block. A punch was attached to the end of the rotation/ translation shaft. In the positioning accuracy test of the punch, the positioning accuracy of the press machine was equivalent to that of the feed screw mechanism with a ball screw. In the input-output characteristics test, the press machine had superior input-output characteristics compared with the feed screw mechanism. Lastly, V bending work could be done by the press machine developed in this study.

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In recent years, many electrically powered vehicles are developed and produced on the whole world. Most of these products are driven by a single large electric motor instead of a gasoline engine. Generally, high power motors have problems that both of the maximum rotational speed and the responsiveness are lower than small motors. We consider Multi-Motor Power Unit can solve their problems. Multi-Motor Power Unit consists of many small DC motors and their outputs are transmitted to driving shaft through gears. We developed Gear-Train-Type Multi-Motor Power Unit that is improved from the basic idea of Multi-Motor System, and it keeps 1:1 gear ratio. Gear-Train-Type Multi-Motor Power Unit has a problem that the center gear loading all motor's output has to be large module. We had proposed new Multi-Motor Power Unit and named it as Tandem-Type Multi-Motor Power Unit. We had developed small-sized Tandem-Type Multi-Motor Power Unit and experimentally measured the maximum torque of it.

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Currently, practical wearable power assisted devices are developed by many companies and universities in Japan. These are also expected to apply to the welfare field. In this study, we had developed a new actuator that consists of more than two small DC motors, and named it as Sliding-Type Multi-Motor Power Unit (S-MMPU). The most significant structural feature of S-MMPU is that the output torque of each motor is transmitted to output shaft by using sliding contact between sphere attached on output shaft of each motor and a flat disk attached on output shaft of S-MMPU. Then S-MMPU has two functional features that are high back-drivability and torque upper limit function. The torque upper limit function is one of important features to guarantee the mechanical safety of the wearable power assisted device for human. To measure the quantitative characteristic of S-MMPU, we had developed prototype equipment of S-MMPU using 8 motors. We had examined the relationship among the output torque, the normal directional force between the spheres and the disk and motor current by using the experimental equipment. We had confirmed that the prototype of S-MMPU has the torque upper limit function from the experimental results.

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The engineering models for the muscle control system of human or animals are discussed in this study. The mechanisms for the signal transduction process inside neuron cells are proposed as structures with sequential parts in that neodymium magnets are embedded. The muscle actuator is also presented in this paper. Both of the signal transduction mechanism and the muscle actuator are applied to a robot hand and the fundamental performances are shown by performance tests.

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Pneumatic actuators have been widely utilized in various fields and have the important role for operating production facilities in plants with their advantages of light weight, low cost, safety, and high compliance. However, driving them needs not only the air supply line from compressor but also many electrical lines from valve controller, making the pneumatic drive system complicated. In this paper, we propose a new pneumatic control system using acoustic communication in an air supply line. This system needs two technical challenges; acoustic operating system and power supply device for each local module. This system realizes simple pneumatic drive system without electrical lines. This prototype system works very well to show the great potential of this proposed system. It controls successfully three pneumatic cylinders independently which are connected with an air supply line of 10[m] in length.

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Pneumatic actuators have been widely utilized in industrial machines with their advantages of low cost, safety, and high compliance. However, pneumatic systems need many air supply lines from a compressor, control lines from a controller, and power supply lines, making them complicated and large. This paper proposes a new control method reducing the number of control lines and power supply lines in pneumatic systems. It needs two key components; Multiplex Pneumatic Actuator Drive (MPAD) and Local Power Supply (LPS) for each local module. This paper deals with LPS from pneumatic line, firstly, we explain its outline design. Secondly, LPS is developed and is tested to confirm its performance. Thirdly, charging method is improved for high charging quantity. Finally, LPS is integrated into MPAD and they is shown that it reduces control lines and power supply lines in operational experiment.

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We had proposed a novel robot design and control method. The proposed robot has movable counter-weights and the robot joint angle is controlled by the position of the counter-weight. However, the proposed control method was affected by parameter estimation errors. To overcome this problem, this report proposes an adaptive control method for counter-weights without parameter identification. The effectiveness of this control method is demonstrated by experimental results of a 2-DOF robot arm.

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We propose a control of the two-degree-of-freedom robot manipulator based on an image coordinates of the eye-in-hand camera. In this method, the control input for each joint actuator are directly calculated using the position and velocity information represented on the image coordinate system of the eye-in-hand camera. The velocity and position information, which is necessary for PID control of the manipulator, can be obtained with low latency by using the high-speed camera and image processing by the FPGA circuit. We examined the performance of the position control of the robot manipulator through the experiments.

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We have developed a PVC gel artificial muscle which is high performance and soft. Therefore, we evaluated the characteristics of the PVC gel actuator using flexible mesh electrode instead of the rigid conventional stainless mesh electrodes in this study. As a result, we have found a material of flexible mesh electrode that shows better performance than that of the conventional PVC gel actuator.

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Pneumatic actuators can achieve compliance and flexibility easily. For the above-mentioned reasons, pneumatic actuators are used in widely fields of medical treatments and industries. However the pneumatic control vale that can control air flow rate smoothly is large scale weigh. The purpose of this study is development of the new flow control valve using torsional vibration. This valve can control air flow continuously and drive by power saving. In this report, firstly we show basic mechanism of the valve and expound the advantage to drive by low power. Next we designed the prototype of this valve using FEM. Finally, we confirmed the principle of the valve.

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We proposed the plasticized PVC gel actuator using electrostatic force. The gel is attracted to electrode applied positive voltage, since the inner negative charge is attracted to positive voltage. The actuator has high responsibility since the gel is moved in air. In this study, the dielectric constant of gel was increased by adding organic particle of polyaniline (PANI), which has high dielectric constant. The dielectric constant and Young's modulus of gel with 20% PANI were 2.8 and 1.6 times higher than pure gel, respectively. The displacement was 1.5 times, since the dielectric constant is effective for this actuator.

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In this paper, we investigate stability criterion of planar legged robot with 2 musculo-skeletal links with McKibben pneumatic actuators(MPA) at static equilibrium, considering redundancy of equilibrium condition and stiffness at the corresponding posture. Based on numerical analyses and the physical experiments, we conclude that stability at a standing posture deeply depends on dynamic characteristics of the McKibben pneumatic actuators, and the resulting body stiffness can be adjusted by combination of internal pressures to the two MPAs and open/close conditions of the air valves.

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Recently, two-wheeled inverted pendulum mobile robots have been popular. They support human locomotion and/or small goods transportation based on inverted pendulum upright controllers. The conventional inverted pendulum mobile robot controls to follow the fixed desired posture angle and wheel velocity. It is desirable to change the control parameters according to the user intention in order to offer comfortable operability of the robot. This paper proposes a user intention recognition system for an inverted pendulum mobile robot and shows experimental results.

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The goal of this study is to propose the concept "Man-powered robotics," which is a methodology to design the robotic system which can control the joint by directly using a power of human's motion as its power source. This paper illustrates the design and the basic experimental results of the prototype of 2 DOF man-powered personal mobility using powder clutches.

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Teleoperation of the robot arm is achieved by capturing the motion of the operator's arm with optical motion capture. However, tracking markers disappear on the way motion capture, optical motion capture can't get operator's posture continuously. So we propose teleoperation system for robot arm by using optical and inertial motion capture. By using this system, we can teleoperate the robot arm continuously.

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We propose a power-assist system using predictive functional control. The system is capable of realizing the motion-assist while predicting operation touque and future trajectory in real time under constraint. Some results of verification are given in order to verify the usefulness of proposed power-assist system.

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A robot system cooperating with gesture instructions using the Kinect sensor is proposed in this research. Specifically, coordinates of right hand is measured by the Kinect sensor, and the robot (omni-directional mobile robot) is moved based on the position data of the right hand obtained from the Kinect sensor. The robot system introduces operation modes of "flick mode" and "following mode". In the flick mode, the algorithm to move the object with the mass and the viscosity by virtual power corresponding to the velocity of the hand is proposed, and the robot follows the calculated position of the object. In the following mode, the robot follows the motion of the hand cooperatively through the "kansei transfer function". In addition, the neural network is used for switching of the two modes. A flick motion and following motion is input into a neural network for the learning of the characteristics of both modes. After the learning, the mode is identified by the neural network from the motion of the hand. The experiment using a suggested system was performed. As a result, a mode was able to be changed from the movement of the hand automatically. In addition, the movement characteristic is changed when the virtual viscosity was changed in the flick motion.

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This study proposes a skill-assist arm with a passive joint that can support precise positioning of an operator. The arm has a passive joint that operator can rotate. In our previous study, the 2-DOF skill-assist arm for assist of drawing line was proposed. However, the arm needs change of actuated and passive joint to avoid singular configuration. Therefore, this study proposes redundant type skill-assist arm which can work without changing joints. In addition to assist of drawing line, this study also proposes method of displaying virtual wall to operator. In order to confirm its availability, we fabricated a prototype and conducted experiments for drawing lines and displaying virtual walls. It is expected that skill-assist arm will be applied to precise works such as welding and surgical operation.

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This paper deals with a development of the remote controlled vehicle type robot using the tablet device. Recently, development of remote controlled robot is performed in various institutions. Joystick or Video game controller is widely used in remote controlled robot. These devices can be used intuitively, but the familiar is required for operation. On the other hand, the tablet device which has Touch panel and Wireless LAN device have become popular in recent years. The tablet device is also a device intuitive to use. In this research, we develop a remote controlled robot using a tablet device as the operation device. The operation experiment results show the operability of the robot remote controlled with the tablet device is the same as Joystick or Video game controller.

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This paper propose a new impedance control method for wearable robots based on pressure distribution between the user and robot. By designing position based impedance control system using pressure distribution directly, we were able to design a system which is more safe and comfortable to the user. In proposed method, pressure distribution is being filtered by evaluation function before being calculated to torque on wearable robot's joints which allows controller to detect the dangerous contact parts more efficiently and more directly. In this paper, we assume a link based structure of wearable robot for the upper half part of the body, and by simulating the proposal method, we were able to indicate its validness.

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In this paper, a control method of power assist based on pseudo-compliance control and force information between human body and system, is proposed and developed. And how to realize an assist control with more power is discussed in this paper.

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This paper deals with the sway control of the overhead crane using 2-DOF control. High operation skill is necessary in the transport with reduced vibration of the payload. However, a skilled operator has been reduced. For this reason, the operation support system that can be easily operated even a beginner is required. Many researchers report that are to be achieved the transport with reduced vibration using a feedforward control or a feedback control. Only a feedforward control can't be achieved the transport with reduced vibration in any operation, and only a feedback control can't be achieved an improvement in operability. Therefore, we use 2-DOF control to design the controller to achieve the transport with reduce vibration and improve operability. The experimental results show the transport with reduced vibration even if the beginner operator is operated.

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In recent years, for the purpose of a power assist and walk assistance of an elderly person, the person with a disability, rehabilitation support, various wearing type robots have been developed. There is the Synchronization-Based Control that used neural oscillators as the control method to enable cooperation movement of a wearable robot and a human. This control method can generate the exercise that tuned to a person. However, parameter adjustment depending on objective movement is necessary and an index and an identification method to distinguish exercise of person of wearing will are demanded. In this study, for an index for parameter adjustment of the neural oscillators, we define the synchrony of the wearer in walking and suggest method using a support vector machine to discriminate it.

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The future human's operation correlates with the past sequential operations. Based on the assumption, we propose the human operation model for predicting the sequential operation. First, the reactive operation models are built by Hidden Markov Model, and the meta- operation models are configured with the tree structure by combining the close reactive operations. Using the meta-operation models, the N-gram model is configured to predict the transition of the operation. The model can narrow down the options for predicting next operation and it also can predict the two or more minions. Experimental result shows the effectiveness of the proposed human operation model.

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In this paper, the aim of this research is navigation method of a wheelchair based on the relative position between a wheelchair and its caregiver. In order to realize the safe navigation, the sensors applied to both assistance grips of the wheelchair, then estimating caregiver's position from the sensors that power acts on. We suggest collision avoidance method and the switching of position between caregiver and wheelchair that considered the relative position relations of a wheelchair and its caregiver. Experimental results using Omni-directional Wheelchair showed the effectiveness of the proposed navigation method.

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Among various medical problems facing us in today's Japan are rapidly aging society, localization of medical doctors, concentrated visits of patients to large hospitals, etc. Development of diagnostic and treatment support systems is considered a current pressing solution to help reduce loads on medical doctors. On other hand, actual diagnosis should be holding a Probe at same position for a long time. So, in this paper, we have developed the ultrasound diagnostic and treatment support robot system to actuate probe for doctor and ultra-sonographer. Therefore, we constructed a new haptic control system to operate on the basis of the 6-axis force sensor value that is attached to the root of the Probe. Then, we confirmed its system response and the measurement accuracy of the tip coordinates, and validated the validity of the measurement. Finally, we conducted an experiment to maintain body surface contact state to follow the body motion, and confirmed the effectiveness of system.

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In this article, we propose a method of human motion identification for Kendo agent. There are three basic attack motion, "Kote-Uchi", "Men-Uchi" and "Dou-Uchi", in Kendo. Although we proposed attack motion prediction method for kendo agent, the agent can not predict his opponent's motion without selection of motion model, which is generated as Gaussian Mixture Model (GMM). Therefore the agent should choose the suitable model to predict the motion. In order to choose a suitable model, current opponent's motion is identified from current his opponent's state and GMMs. The motion identification method is evaluated by carrying out some experiments.

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In this article, we propose attack motion prediction with automatically motion model selection. In the 1st report article, we assumed that the opponent's motion type is known when he attacks. However, in the fact, the agent can not know the opponent's motion beforehand as well as us. Therefore the agent needs ability for knowing the motion type in order to predict his attack motion. For that reason, attack motion prediction method which was described in 1st report, and attack motion identification method which was illustrated in 2nd report are integrated for the Kendo game with human. Finally the more practical attack motion prediction method is proposed and the efficiency of it is illustrated in verification experiments

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This paper discusses an advanced operational assistance system for a transfer system with vibration elements. The transfer system such as a crane is manipulated typically by the operator. However, the operator skills with the vibration suppression, the short time transfer, and the high precision positioning are required to manipulate the transfer system. In order to realize the operator skills, the evaluation system of the operator's motion characteristics and the operation assistance system for vibration suppression are proposed in this study. In the evaluation system, the ability of the vibration suppression by the operator in the frequency domain is clarified. And, the vibration including the natural frequency with which the operator is difficult to suppress the vibration can be suppressed by the assistance system. By the proposed system, the vibration suppression and the high precision positioning can be realized.

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We have proposed an extraction technique of action rules from time series on human actions as situations obtained by long-term observation. In the proposed method, HMM and IF-Then rule style are used in consideration of readability of obtained action rules. In this paper, the usefulness of the proposed method is examined with two dimensional time series data on human actions.

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In this paper, aiming at human-robot cooperation using electroencephalogram (EEG), we studied on EEG when the load changed during a task. EEG and electromyogram (EMG) signals were recorded during a crank rotation task, where the load of the task was changed at random timing. Frequency spectra of the recorded EEG signals were analyzed, and difference between ON and OFF of the load was observed.

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This paper introduces a map building method using a human-following robot. The map built in this study is a simplified hybrid map based on both of metric and topological information. In this paper, important points in the environments are detected by monitoring human movements while following by the robot. Especially, intersections are detected as important points and topological relationships among intersections are derived. The proposed system is constructed by RT components of following a target human, obtaining information for map building and etc. In this paper, details of the developed components and some experimental results are shown.

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The purpose of this paper is to apply a subliminal calibration to existing machines. The operability is solved by applying the subliminal calibration to the user interface. In our previous work, the subliminal calibration is necessary to change the dynamics model of the operation target device. Therefore, we propose a variable impedance joystick in this paper. The variable impedance joystick can change its dynamics parameters in real time. The parameters of the joystick are applied the subliminal calibration and the performance is experimented. Finally, the results suggest the effectiveness of the proposed joystick.

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In this paper, we propose a method to estimate the geometrical relationships between servo-brakecontrolled caster units arbitrarily located on a moving base. The pose of the caster units is estimated by the extended Kalman filter based on only the velocity information of each caster unit. Since the system controlled by servo brakes is driven by a user-applied force, the user can arbitrarily select the input signals of velocity information. Therefore, we also suggest a simple pattern that enables users to provide sufficiently rich information for relationship estimates. Finally, we validate the proposed method in an experiment using a mobile robot platform with double-wheel caster units.

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We previously proposed a semi-active operation assist handle for manual conveyance of flexible part. The assist handle consists of a handle, a variable damper and a mechanical spring. The assist-handle can be attached to a general hand cart, through which a human operates the hand cart. In this paper we verified the work efficiency of manual conveyance of flexible part by using the assist-handle. For this purpose, a one-degree of freedom force display device was used to simulate the behavior of the assist-handle, the cart and the flexible part. Furthermore, we considered the work efficiency by evaluating the attenuation of the residual vibration of the flexible part and the conveyance time.

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This paper proposes a control method for the task space obstacle avoidance problem of the robot manipulator. Proposed method utilized a vision based model predictive controller (MPC) in order to consider about structure and task space condition. In the method, current position of the obstacle is visually obtained and desired trajectory of the MPC controller will be updated to avoid the detected obstacle position. Details of the vision based MPC controller is mathematically described Experimental system using parallelogram linkage manipulator and Video-Tracker (the motion capture system) is developed to examine the proposed method. Experimental results show the effect of the method.

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This paper proposes a method for planning the base position of mobile manipulators to perform the picking tasks. By using our proposed method, we can find a base position of a mobile manipulator where the manipulator can pick up an object placed at any position of a pallet. We first explain the method for solving inverse kinematics taking the collision between the robot and a pallet into consideration. Then, we show a method for determining the base position. The effectiveness of the proposed method is confirmed by numerical examples.

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This paper proposes a method for lifting up a big object by a dual-arm manipulator. To lift up an object, the robot first rolls an object on a table. To plan the rolling motion of an object, we consider classifying the facet of the convex hull into three categories. Based on the classification, the rolling motion can be planned by searching for the facet graph where it shows the connectivity information of each facet of the convex hull. We also show a method for grasp planning of a big object by using a dual-arm manipulator. The effectiveness of the proposed method is confirmed by using a numerical example.

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We developed the spark examination device consisting of a grinder, a motor and a camera and an ingredient analysis program using the image analysis. The spark examination device produces a spark on a constant condition by controlling grinders with a PC and photographs the spark. I extract the characteristic of each steel materials ingredient from the spark image which I photographed by image processing by the ingredient analysis program and distinguish steel materials ingredient. These device and analysis program allow the automation of the spark examination to need an expert technique and the quantitative evaluation of the steel materials ingredient.

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