The mosquito proboscis is good model for medical painless needle. It consists of 7 parts, which are labrum, two maxillas, two mandibles, pharynx, and labium. Among them, labrum and two maxillas play important role of inserting proboscis to skin. Three paired silicon microneedles are fabricated: one is central straight needle imitating labrum, others are side jagged needles imitating maxillas. However, they are easily buckled and broken due to their fairly thinness. We noticed mosquito's labium, which supports other 6 parts, and prevents them from buckling/breakage. A guide tool for needle insertion is proposed and fabricated, which is made of polydimethylsiloxane (PDMS) rubber sheet and is machined a narrow groove. Through the groove, three needles are inserted to the skin. Even if they are buckled, the sidewall of groove supports them at contact points, preventing them from breakage.

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In this study, we examined an effect of miniaturization on a magnetically driven fish-like microrobot. We fabricated a microrobot reduced to a scale of half our previous one and evaluated its static and dynamic characteristics. Due to the friction of the rotation axis, the deflection of the tail fin was largely decreased. As a result, the swimming speed reduced compared with the previous robot. In order to solve this problem, the magnet volume was doubled to obtain torque enough to overcome the friction. In addition, since the miniaturization doubled the driving frequency showing a peak of swimming speed, we developed a new drive system suitable for miniaturization.

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In this paper, a novel individual operation method for magnetically driven underwater microrobots has been presented. This method is based on mother ship concept, in which a cm-sized mother robot can carry a small child agent. To obtain individual operation of the mother ship and the child agent, difference in driving frequency between them was utilized. We could successfully control individual motion and release the child agent from the mother ship by changing the frequency.

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We have been working on high power joint mechanism by mimicking locusts leg structure. The proposed joint mechanism, which consists of two motors, three pulleys, two wires, one spring, and one link, controls the output link using the tension provided from the motors to wires connected to the link. Operation of either of the two motors enables flexional and extensional motion. With the joint mechanism put into flexion, simultaneous operation of two motors accumulates power in the spring. Shutting down one motor releases power accumulated in the spring to realize rapid motion. Power produced during rapid motion decreases by viscosity resistance from passive motor. Therefore, links length where viscosity resistance of passive motor is the minimum is found to gain high output power. In this paper, viscosity resistance of the joint mechanism was analyzed. The result of analysis, it was shown that viscosity resistance during rapid motion is possible to decrease by shorten output link.

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In this paper, we developed a system for performing mobile robot navigation from the position of the object information obtained from multiple sensors using Robotic Localization Service (RLS). We report on the validation configuration and operation of the system was constructed.

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In this paper, we intend to design goods management system framework in the Kukanchi based on the Robotic Interaction Service (RoIS) framework. In the RoIS framework, goods management system work as a functional component. Therefore, we defined goods management system as Goods Localization Component that notifies goods location change events and supports goods position query. To realize cooperation between Goods Localization Component and other Robotic functional modules, we designed interface for these two functions. In addition, we designed internal structure of Goods Localization Component. Goods Localization Component is composed of goods localization sensor layer and localization software layer includes measurement, aggregation and transformation layer. To verify our framework, we developed goods management system for storage furniture as a sample system. By the verification experiment, we show that verification system could detect four kinds of events correctly.

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Cities, where various functions are concentrated in limited area, have been suffering from chronic space shortage. High-rise buildings and underground have been developed to increase space use efficiency. However, those developments just lay out the spaces which are expanded in plane into vertical; there are the physical and monetary limitations. Therefore, the spaces which can change its functions easily/automatically depending on the situations are necessary to increase space use efficiency. Therefore, we have proposed smart variable space which realizes various functional spaces by changing its modules dynamically. In previous research, we developed a bedroom-type robot module. In addition, the path planning method is also examined. However, there is a problem with localization method. Therefore, in this paper, a new localization system was proposed, and then, its availability was examined.

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The authors proposed the assistance system according to usermodels using some robots. Some robots are smart robot, mobility robot and ZigBee Accelerometers. In this research, we use Apripoco as smart robot and table robot as mobility robot. Table robot and Apripoco work cooperatively function, standing-up assistance function and walking assistance function. ZigBee Accelerometers recognizes which user use the system and user's condition. The system assists users according to physical disability to recognize user by zigbee sensor. In this research, the authors divide usermodels by three. First, elderly people who can walk without difficulty. Second, elderly people who have a little difficulty. Third, elderly people who need minimizing care.

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This paper presents a method to predict occupants' individual thermal comfort based on indoor and outdoor environmental information using a sensor network. A part of values are chosen from the network and are associated with the value which needs to be predicted. We utilize neural network to associate the values for predicting a human's thermal comfort. In this paper, we use accelerometer and GPS data to determine occupant's activity, while at the same time using a number of temperature and humidity sensors to measure environmental parameters. The experimental results shows that unspecified sensors are chosen properly and used for predicting the desired value.

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We constructed a PID feedback control system for newly developed dragonfly-type flapping robot. Each flapping wing is driven by a scissors-swing-motor (SSM), which consists of a couple of voice-coil-motors (VCMs) used in commercial hard-disk-drive. Angle of each VCM arm is detected by a resistance potentiometer, and it is used as feedback signal for the PID control. A continuous flapping motion oscillating according to a sine function of 2〜3 Hz has been well achieved by a simple PI control. To follow up a step-function signal, full PID control is necessary to minimize the settling time. The two VCMs in a SSM are so conjugated that the motion of VCM arms are largely affected by each other. Optimum parameter set for the PID control depends on the wing shape, thickness, and the angle between two arms in the SSM.

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Recently, the use of a bio-inspired oscillating elastic fin has been proposed as an alternative propulsion mechanism in water. It is thought that the new mechanism will improve efficiency and safety, relative to the screw propeller. The optimum elasticity of the fin is not constant and changes based on swimming speed and task. However, it is very difficult to exchange fins of different stiffness while moving. We have developed a propulsion mechanism using a variable stiffness fin with torsional rectangular elastic plates. The stiffness of the fin was changed by the torsional angle of two rectangular elastic plates. We discussed the behavior of the fin, thrust force characteristics, and the flow field surrounding the fin in a still water and an uniform flow of water.

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This paper studies the process in which soldier crabs cause group behavior. And, we focus on interaction between "robot" and "crabs' group". On the experimental, this paper considers three cases. First case, there are only soldier crabs(16) in the field. In the second case, there are the stationary robot and soldier crabs in the field. On last case, we use the moving robot in the same situation. These experimental results are analyzed by two schemes as follow. (1) We count directions where one crab advanced any four patterns(approach, leave, wall, the others). (2) We assume crabs moving same time to be same group, and count those of number. From the analyses, soldier crabs have the tendency to approach other crabs. Moreover we got knowledge that the motion of the robot activate soldier crabs' group behavior.

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This paper is aimed at developing analysis and observation system for understanding principal of group of soldier crabs. Especially, in this paper the mobile robot interacts with sixteen soldier crabs. For the experimental analyses, this paper adopts two settings. In the first setting, there are only sixteen soldier crabs in the field. In the second setting, there are the stopping and moving robot and sixteen soldier crabs in the field. These experimental results are analyzed by image processing using OpenCV. From the analyses of two experiments, group of soldier crabs repeat independent behavior and collective behavior. In addition, both iteration has period of 102s. This result suggests that the behavior of soldier crabs has period and this behavior is robust.

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Caenorhabditis elegans (C. elegans) is one of the simplest multi-celled organisms whose body is composed of about 1000 cells. This animal has only 302 neurons devoted to information processing, and its interconnecting structure has been completely revealed anatomically. This has given an advantage to using C. elegans to reveal primitive information processing mechanisms in neural circuits. For this reason, various neural models have been proposed; however these previous models did not consider the interactions among the nervous system, body, and environment. Accordingly, the neural mechanisms to direct body movement from acquired environmental information have not yet been completely revealed. Against this background, this paper proposes a simulation platform including environmental, neural, and body dynamics models. We then applied the proposed platform for simulation of chemotaxis. The results confirmed that the proposed models can simulate attractant behavior to NaCl.

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This paper describes an insect-inspired wall-climbing robot with microfabricated adhesive pads. The pad is composed of a glass pad which adheres to the wall by meniscus force, and a PDMS pad which exhibits large friction. The pad also has a porous layer which is impregnated with water and supplies and withdraws water on the glass pad. Adhesive force of the pad was measured on a glass plate. The results showed that a constant adhesive force of 400 mN was obtained. Furthermore, a hexapod robot with the composite adhesive pads on its feet was developed. The robot walked on a 40 degree slope with wave gait.

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In this study, we intend to develop three-dimensional (3-D) piezoelectric micro power generation devices using a 3-D ceramics molding process based on microstereolithography. In this method, High concentration slurry of ceramics nanoparticles is introduced into 3-D polymeric mold fabricated by microstereolithography, and then the polymeric mold is thermally decomposed. After sintering of green body, any 3-D ceramics microstructures can be produced. In preliminary experiments, we fabricated piezoelectric cantilevers using slurry of BaTiO3 nanoparticles. After polarization treatment of the piezoelectric cantilevers, we confirmed that they could generate output voltage due to apply pressure. As the first trial, we fabricated a sintered body of a helically-curved power generation device. We will evaluate the performance of the device in experiments.

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In this study, we established a method to fabricate three-dimensional (3D) metallic movable microparts by the combination of electroless plating and laser ablation. In this method, a polymeric movable microparts with anchors made by two-photon microfabrication are metalized by electroless plating, and then the anchors are removed by laser ablation using a femtosecond plused laser. As a result, a metalized freely movable micropart restricted to a shaft can be produced. We succeeded in fabricating sophisticated 3-D microrotors by optimizing the experimental conditions of both electroless copper plating and laser ablation.

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In this paper, we demonstrated that a metalized microrotor could be rotated by optical trapping. The metalized microrotor was fabricated by the combination of two-photon microfabrication and electroless copper plating. By scanning a low-power laser beam, we succeeded in driving the metalized rotor at a high speed. The rotation speed of the rotor was proportional to the rotation speed of the laser beam. We also analyzed the radiation pressure exerted on the rotor. As a result, the driving mechanism of the metalized micorotor was investigated. The high-efficient optically driven micromotor will be useful for functional lab-on-a-chip devices.

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Biological molecular motors, motor proteins, work in fish melanocytes to change their colors. Inspired by these fish melanocytes, we have envisioned to realize an optical device powered by motor proteins. To this end, we developed a series of requisites to realize the device in a step-by-step manner. In addition, integrating the developed requisites, we made attempts to assemble the optical devices. However, the assembled devices did not work as we intended. We will discuss the reasons, and show possible ways to successfully realize the optical devices.

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Biological molecular motors, motor proteins, work in fish melanocytes to change their colors. Inspired by these fish melanocytes, we have envisioned to realize an optical device powered by motor proteins. In order to realize the optical device, we have to explore possible designs of the device to optimize its function. However, such exploration is hampered by laborious experimental procedures. A computer simulation is useful for such exploration. Here, using a computer simulation, we obtained design guidelines for the optical device.

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We have developed a new power assist arm for handling heavy loads using large pneumatic muscles. We chose to use the pneumatic muscles from a viewpoint of safety, but large actuators were required for heavy loads. As a result, it was expected that control becomes difficult due to the increased air flow requirement. Therefore, to optimize the hardware, we used silicon rubber filled pneumatic muscles in order to reduce a flow of air. And we increase the total cross-sectional area of a flow. On the control side, we developed an original pneumatic muscle model and the torque control based on it. Furthermore, we developed an impedance control system and successfully implemented it as part of a working power assist arm for handling heavy loads.

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In this study, the robot system which follows the movement of the human hand is suggested. In the system, the movement of the human hand is obtained using the Kinect sensor, and the three-dimensional position of the human hand is send to the robot. The robot generates the reference trajectory based on the position which has been sent from the Kinect sensor. The position of the human hand is converted into the smooth motion using KANSEI transfer function as the reference position, and the robot follows the smooth reference position. As a result, the system which followed the movement of the hand smoothly is realized.

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Recently, rapid aging advances in our country, the patient who had a decline in the physical function by aging or illness increase. Many types of assist devices are developed to keep their Q.O.L. in their independent day-life. It is important to reflect user's intention to the device and we focused on a brain wave which is expected as a means of communication of user's intention. An EEG is used among the brain waves and we aimed at using it to apply for a brain computer interface (BCI) system. In this study, we measured an EEG data during arms motion and examined the data obtained in the fast Fourier transform.

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Recently, the personal mobility have been developed to reduce an environmental impact as a measure against global warming. Electric power assist bicycles are the most used for cheapest price under the classi cation of the personal mobility. Segway and the other personal mobilities have high performance functions such as self standing control. Electric power assist bicycles have only one function such as assistance of driving forth with torque sensor and speed sensor. On the other hand, the bicycle parking lot is short in highly populated urban areas. Therefore, the purpose of this research is to develop a standing personal mobility " Oteller" for increasing space efficiency of bicycle parking lot by miniaturizing a body using a driving wheel. Oteller treads at three point using two assistant wheels to suppress the instability of the body without the sensors for self standing control. Turning is performed with moving weight balance. In this paper, it explains about the design of Oteller and the run experiment using a prototype.

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This paper presents a collision force suppression mechanism that can be installed in the joints of the manipulator of a human-friendly robot. The collision suppression mechanism can reduce collision forces without using any sensors. The mechanism consists of an outer circular disk, an inner circular disk, torsion springs and compression springs. If the manipulator with the suppression mechanism collides with an object, it disconnects from its joints, and it moves in the direction of the collision force depending on the spring reaction force. Moreover, if the object is eliminated, the manipulator connects back to its joints using the spring forces.

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This paper presents a collision force suppression mechanism that is installed in the joints of the manipulator of a human-friendly robot. The collision suppression mechanism consists of an outer circular disk, an inner circular disk, torsion springs, and compression springs. If the manipulator collides with an object, the suppression mechanism disconnects the manipulator from its joint, and it moves in the direction of the collision force depending on the spring reaction force. Moreover, if the object is eliminated, the end-effector follows a target position with a collision force control method. Through collision experiments, the effectiveness of the mechanism is verified.

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We have been developing the Proton Beam Writing System to fabricate micro chemical chips. The micro fabrication process using the imprint technology was verified as one of the proton beam writing system. Though the Ni molding with micro structures was fabricated using the electroless plating, there were problems such as the thermal expansion of the resist and the adhesive force of the Ni plating. By solving these problems, the Ni molding with micro structures succeeded in using the electroless plating. In addition, the thermoplastic polymer, PET succeeded in imprint using the Ni molding molding. The proton beam writing system has the potential to be able to fabricate the micro chemical chips incorporating novel sensors and filters.

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In this paper we demonstrate new fabrication process of micro holes using super absorbent polymer (SAP). In recent years, micro meter order processing is enabled by the development of MEMS technology. However, making structures of about 1 pm is difficult while hundreds and tens of nanometer patterning can be done by e-beam lithography and UV lithography is suitable for making patterns greater than several micro meters. So we propose a method to fabricate micro-order-structure by using SAP patterning. In this process, we made a stencil mask of SU-8 for Oxygen-RIE. Using this method, we patterned 5 μm, 10 μm holes. Then SAP was swelled water, the hole diameter shrunk and hole depths of increased. The aspect ratio of holes became about 11 times at 5 μm patterning, and about 14 times at 10 μm patterning after swelling. This fabrication can be applied to micro-TAS and lab-on-a-chip.

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We demonstrated the fabrication of polymer micro-needle electrodes that may be applicable as flexible electrodes in brain-machine interface. For this application, needles must be stiff enough to penetrate the stratum corneum and conductive layer of needle surface must be protected from peeling off during the insertion. Thus, we fabricated composite micro-needle arrays using two polymers with different elastic modulus and coated with parylene on the silver membrane of the conductive layer. We experimentally verified that needle strength improved, and when the thickness of the parylene was 50 nm, the conductive membrane was successfully protected while maintaining conductivity.

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We proposed a novel electrostatic linear actuator using fringe electrical field and a trenched ferroelectric. This actuator can be driven at low applied voltage due to using an electret. A comb-shaped polymer electret with grounded base electrode and a comb-shaped counter electrode are interdigitally fabricated on an insulating substrate. The driven voltage is applied to the counter electrode. Between electret and electrode, fringe electrical field is generated and the electrostatic force is applied to the trenched ferroelectric. The narrow gap such as several tens micrometer is achieved due to support the ferroelectric by the linear rails with ball bearings (200 μm in diameter). The maximum force of actuator was 0.02 mN/mm^2 at 300 V applied.

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Biological molecular motors, motor proteins have large potential for engineering application. We previously reported an optical device driven by motor protein that is designed by mimicking a molecular system of fish melanophore. This device, however, does not equip a regulating system, so that reaction is one-way, not reversible. To improve this, in this paper, we propose and develop a molecular photoswitch by fusing the photo-sensor protein LOVJa and motor protein.

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The study proposes a skill-assist robot arm that can support the precise positioning in operation of human. The skill-assist robot arm has actuated and non-actuated joints; it consists of an underactuated manipulator. The non-actuated joint is driven with the output point of the arm operated by human, so that its displacement is determined passively. Then, the actuated joint is controlled to achieve the precise positioning of the output point. Using the skill-assist robot arm, thus, the displacement behavior: velocity, acceleration is adjusted by the operator; the position is compensated by the arm. The proposed arm can perform both precise positioning and adaptable adjustment of the motion to achieve high level skill by the cooperative operation of the robot and human. The study proposes the mechanism of the skill-assist arm and its control method. Furthermore, by actual drawing figures with the fabricated skill-assist arm, its availability is confirmed.

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This paper proposes an assist handle for manual conveyance of flexible parts and its semi-active operation assist control. 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 and a human operates the hand cart through the assist handle. The controlled system consisting of the assist handle, a hand cart and a flexible part is represented as a bilinear system. The semi-active operation assist control is designed by using the bilinear optimal control theory. The effectiveness of the assist handle and the semi-active operation assist control are verified by simulations.

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In this paper we design a new crane tele-operation system considering power assisted conveyance using zero phase notch filter and model predictive control. The zero phase notch filter enables to modify frequency characteristics of operating torque without signal distortion on the line in oder to suppress vibration of the load-rope of crane. The model predictive control enables to suppress the vibration in comparison with conventional system sufficiently. Some results of simulation and experiment are given in order to verify the usefulness of our proposed system.

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In this study we realize a power assist based on force operation motion estimation using model predictive control with a combination of the surface EMG sensors and the force sensor. Some results of verification are given in order to verify the usefulness of proposed power assist system.

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Silicon dioxide electret induced by highly doped potassium ions will be demonstrated by forming on a comb-drive actuator. The comb-drive actuator made of silicon on insulator (SOI) substrate is oxidized with bubbling stream of KOH solution to form a silicon oxide film including potassium ions on the etched side-walls of comb electrodes uniformly. After bias-temperature (BT) procedure at about 900-1000 K and 100 V was applied to the device, we have confirmed 40 V built-in potential difference between the opposing comb electrodes. In order to obtain higher potential electret film, we have fabricated a "glass" comb-drive actuator.

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Plasma etching, during micro fabrication processing, is indispensable for fabricating MEMS structures. During the plasma processes, two major matters, charged ions and vacuum-ultraviolet (VUV) irradiation damage, take charge of reliability degradation. The charged ions induce unwanted sidewall etching, generally called as "notching", which causes degradation in brittle strength. Furthermore, the VUV irradiation gives rise to crystal defects on the etching surface. To overcome the problem, neutral beam etching (NBE), which use neutral particles without the VUV irradiation, has been developed. In order to evaluate the effect of the NBE quantitatively, we measured the resonance property of a micro cantilever before and after NBE treatment. A parameter of surface damage (δE_<ds>) was then compared. Although plasma processes make the initial surface of cantilevers damaged during their fabrication, the removal of that damage by NBE was confirmed as the reduction in δE_<ds>. NBE will realize a damage-free surface for microstructures.

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Carbon nanotube (CNT) is a promising material as nano sensors for mechanical and physiological measurement. Although there are many studies on mechanical and thermal properties of a single CNT in vacuum, thermal conductivity of the single CNT in liquid are not well investigated. Here, we propose measurement of thermal conductivity of a single CNT in liquid using optical assembly and fluorescent temperature measurement in liquid. Roles of the sensors are temperature sensing and heat input to the CNT by infrared laser. The sensors are fixed to both CNT edges by optical tweezers and heated by infrared laser. Thermal conductivity was evaluated by measuring the temperature variation of each sensor and calculating heat quantity passing through the CNT. In this paper, we demonstrated assembly of CNT and nanosensors and measurement of thermal conductivity of CNT in liquid. From experiments, average thermal conductivity of a single CNT in liquid was (3.2 ± 0.6) × 10^3 [W/mK].

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Recently, it is considered that in vivo transfection is an important technique used in biological research and drug therapy development. In this paper, we report a novel implantable microsystem for delivery of nucleic acid drugs to mice kidney. The microsystem consists of pneumatically actuated balloons, renal case, and pressure-supplying port. Renal pressure-mediated transfection of plasmid DNA was successfully performed by using the microsystem implanted into mice. The highest expression of transfected plasmid DNA was obtained when the microsystem was activated at 60 kPa of pneumatic pressure for 10 s. The developed microsystem is valuable for in vivo gene functional analysis, diseased animal development, and preclinical studies of gene therapies.

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This paper presents a MEMS potentiometer that uses a connection through a probe dipping into conductive liquid. We proposed a connection using conductive liquid to allow low physical restrictions. A connection using conductive liquid employs a probe electrode that is dipped into aμPool filled with a conductive liquid. The proposed potentiometer can drastically reduce the physical restrictions at the contact point of a probe electrode. We designed two potentiometers according to applications. A rotary potentiometer and a cylinder type linear potentiometer were designed and presented. Two developed potentiometers based on the connection using conductive liquid could detect displacements as designed.

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This study proposed robust EMG measurement technology, and examined the motion identification based on the AIEMG feature from a subject's forearm surface EMG. Several subject's motion identification experiment was conducted, and it was confined that the form of fingers could be identified with the probability of 90% or more.

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In this study, we developed a knee assist device with a variable stiffness mechanism. Since the variable stiffness mechanism proposed by the authors can realize large stiffness variability, small-size and lightweight, the stiffness of the developed assist device could be adjusted from 0.0[Nm/rad] to 20[Nm/rad], and its weight became 450[g]. A preliminary walking experiment with the developed device was carried out on a flat treadmill, and we evaluated the effectiveness by using Electromyogram.

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In this research, we are aiming to develop an inverted pendulum type transportation robot to effectively carrying a heavy object with a high center of gravity in a complicated space. Since an inverted pendulum type robot can be moved by very small external force to the back and forth direction maintaining its balance based on the principle of an inverted pendulum, it can act as a power-assist transportation robot. This paper proposes impedance transportation control for the robot to realize a power-assist motion and increase its stability. By adopting the proposed control, an operator can move the robot while taking the reaction force corresponding a virtual mass and viscosity from the robot. Experiments were conducted to confirm the effectiveness of the proposed method.

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Practical realization of service robots is in demand to compensate for the shrinking workforce due to aging populations. Robotics technologies can help support our aging populations in both social and work environments. We developed a manual control link mechanism using magnetic particle brakes at each joint in place of servo motors. This mechanism can be used to support a positioning action passively. It meets the requirements of safety, low acoustic noise, and high efficiency. In this paper, we describe the design and the dynamics analysis of a prototype mechanism, including the self-weight compensation, which is realized by appropriate driving of the magnetic particle brakes, and the resistance torque display to hold tilted position of the link.

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Finishing processes such as deburring are performed on a wide variety of products in various quantities by workers on a piece-by-piece basis. Accordingly, the accuracy of the product depends on the worker's skill. To solve this problem, the bilateral control system is applied to machining support system. The aim of this research is to develop a machining support system via bilateral control system which can control the machining trajectory by reflecting the operation force. This system has the variable connecting force construction for master and slave robot based on the symmetrical bilateral controller. This construction is useful to change the feature of system according to machining condition dynamically.

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In high-variety low-volume manufacturing, parts are typically processed by handwork in order to minimize production cost and lead time. However, when a precise finishing process is required, handwork has problems of processing error and insufficient processing accuracy. To address these problems, we developed a fixture-type machining support robot with a parallel link system, and propose grinding force control based on hand stiffness estimation as the finishing process support system.

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Efficient human movement requires to adjust both environment impedance and biological impedance. We suggest that cutaneous sensation contributes this impedance adjustment. Our objective is to develope movement support technology by vibrating leg joint parts. In this paper, as a preliminary step, we evaluated vibrotactile threthold of the leg joint and effects of stimulus locations and simultaneous stimuli.

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Humans can adjust own impedance with environment impedance. This study has a hypothesis that humans use impact vibrations generated by hitting environments with a part of body for adjusting own impedance. Although the relationship between muscular activities and perceived impedance should be evaluated to investigate the hypothesis, it is hard to control muscle activities voluntary. So we propose an evaluation method for human impedance adjustment ability using an artificial musculoskeletal mechanism which has variable stiffness function to substitute a part of body. This device contributes to investigate relationships between perceived impedance and motion control under several stiffness conditions. We developed a prototype device. We confirmed that instantaneous vibrotactile stimuli which interrupt impact vibrations could affect the human impedance adjustment ability.

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Human motion is performed by adjusting their impedance to environmental impedance. However mechanism behind the human impedance perception is still unclear. Therefore, our goal is to clarify the mechanism behind the human impedance perception from a view of cutaneous sense involvement. In this paper, we developed acoustic vibration sensor, and evaluated Vibrational Characteristics of it, and investigated the relationship between muscle activity and vibration propagation of human body. The involvement of cutaneous sense in impedance perception is suggested in the result of experiment.

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The goal of our study is to develop a virtual walking system using a haptic device on sole of feet. In this paper, we conducted sensory evaluation tests under conditions with various floor surfaces and various shoes. The results show the resolution of sole of feet with shoes is 20〜30mm. Next, we measured plantar pressures while healthy subjects step on difference floor surfaces with various shoes in order to decide required performances of the haptic device. The results show all subjects were able to perceive the differences of the plantar pressure with 1〜4 in the difference of the normalized pressure.

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