We have developed a rehabilitation system for upper limbs, “PLEMO-P1”, which utilizes ER brakes as torque generators and is one of the passive haptic devices. To detect abnormalities of patients, we developed a new sensing device and installed it on the grip of the PLEMO-P3. In this paper, we establish effective training methods with PLEMO-P3. We compare several kinds of information from the sensor system (grasping force, reaction force against a plane, range of a wrist) and traditional assessment of stroke (BRS, FMA, SIAS and STEF). We could found effect of training and strong correlation between them. We suggest a training method with PLEMO-P3 depending on the results of the evaluation tests.

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Body weight support treadmill training (BWSTT) is a way of gait training. Patients walk on treadmill with body weight support. We developed BWSTT system with movable mechanism and MR actuator. Our system has improved the problem of body weight support irregular and uncontrollable center of gravity that a practical BWSTT system has, with movable mechanism and MR actuator. We conducted validation test of the prototype with healthy person. Validation was to compare the normal walking under no body weight support walking and the body weight supported walking by using an electromyographic(EMG) measure and some data from the control of movable mechanism. Through the validation test, we confirmed the effectiveness and safeness of our BWSTT system.

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Movements of the upper limbs commonly affect activities of daily living. It is important for the aged to exercise for maintenance or recovery of upper limb functions, through detecting depression of their function, in aims to decrease the number of needing care or support aged and to stimulate engaging society of them. Application of robotics and virtual reality technology makes possible for quantitative evaluations of upper limb functions to enhance the qualitative effect of training. In this paper, the authors report on 2-D force display system and virtual maze software, which can be use as a test method for motion functions of upper limbs. This paper describes the effectiveness of the system through repeatability of the experiments and discriminability between motion functions of abled and disabled persons. The paper also shows the necessity of applying base data of the same age group for evaluations because some differences were detected between experimental results of able bodied youth and elderly.

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Force display systems are important in virtual reality and other applications. For force display system, it is the most important thing to ensure the safety mechanically in order to prevent operators from hurting. The conventional force display systems are active systems with actuators but these systems may become dangerous when going out of control. On the other hand, passive force display systems with only passive elements are thought to an effective method for assuring the inherent safety. In this paper, we evaluate force display ability about a 2-D passive-type force display system using fast-response MR (Magneto-Rheological) fluid brakes in order to apply this system to the virtual reality techniques and so on.

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Strengthening muscle force by training, e.g., an isokinetic exercise is widely used in rehabilitative activities or sports rehabilitations. However, many conventional isokinetic exercise machines are expensive because of their actuation devices and safety systems (hardware and software). In this study, we have developed highly safe isokinetic exercise systems using only brakes with functional fluids (Magnetorheological Fluid or MR Fluid). Because of rapid response of these fluids, such a machine has good response property and controllability. In this paper, we describe basic concept and characteristics of Isokinetic Exercise system using MR fluid brake and its experimental results. In particular, high-speed (900deg/s at an elbow joint) training can be realized in this system.

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An experimental investigation is carried out on the colliding behavior of acrylic particles in a cylindrical vessel agitated by a water jet. The water thus injected into the bath is circulated with a pump to keep the bath depth constant. The frequency of collisions is measured with a noise meter and a digital video camera. The diameter of the cylindrical vessel, the aspect ratio of the bath, the number of the particles, the diameter of the particles and water flow rate affected the frequency of collisions. An empirical equation is proposed for the frequency of collisions.

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Investigation on mass transfer from foods such as pig bones to water contained in a cylindrical vessel of extraction processes has been carried out based on a model experiment. The water bath is agitated by a water jet injected from a centered bottom nozzle. The mass transfer coefficient is estimated from the heat transfer coefficient for an ice sphere because analogy between mass transfer and heat transfer holds under turbulent flow conditions. An estimation method of the mass transfer coefficient is proposed.

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Photoelasticity is applied to measure the shear strain of the plastic lenses of glasses. The lenses of CR-39 are fixed to two kinds of glasses frames, the old frames and the new ones whose rim lock mechanism is improved to reduce the strain of the lenses. The measurement results show that the strain of the lenses attached to the new rim lock mechanism decreases by about 33% on the average of whole area of the lenses, compared with the old mechanism. At the center of the lenses, however, the strain of the lens attached to the new rim lock mechanism is roughly the same as that of the lenses fixed with the old rim lock mechanism. The shear strain is of the order of 10^-4, which brings to the change of lens' refractive index of 10^-5 . The measured data can be the basis to investigate how much the strain of glasses' lenses deteriorates the quality of vision.

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To reveal the gas bubble motion in the field of hydromagnetodynamics by means of optical direct observation, we constructed the new experimental system that is consist of non-electrically-conducting gas phase and transparent electrical conducting liquid phase, imposing high magnetic field on the system. In this study, argon gas and sodium chloride solution were used as gas phase and liquid phase, respectively. The Lorentz force was able to be comparable to viscous force and inertial force acting on a gas phase bubble, because the Hartmann number was 2.3 and Reynolds number was 430 for a 3mm diameter argon gas bubble under the imposition of 7T magnetic field. A series of continuous pictures of a single bubble rising up in the saturated sodium chloride solution was taken by using high speed camera, under 0T, 3.5T, and 7T static horizontal magnetic field. From these pictures, the rising velocity of the single bubble was measured. The medians of measured velocities are 0.240m/s with no magnetic field (0T), 0.240m/s with 3.5T magnetic field, and 0.232m/s with 7T magnetic field, respectively. That is, the rising velocity decreased with increase in the magnetic field intensity.

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Dynamic behaviors of ultra-low-carbon mild steels were experimentally examined in order to clarify the contribution of the pure ferrite phase on the strain rate sensitivities. In the experiments, two types of mild steels, namely type A steel with no solute carbon in which whole carbon was scavenged as titanium carbide and type B steel with interstitial solute carbon which causes the increase in yield strength due to the strain aging were employed, and dynamic tensile tests were performed on these steels before and after strain aging to clarify the influence of the strain aging on the strain rate sensitivity by comparing the mechanical behaviors of both steels. From the experimental results, strain aging seemed to increase flow stress, however its amount was getting smaller with increasing strain rate. Furthermore, from the TEM observation, it was found that static deformation formed the dislocation cell structure, on the other hand, the dynamic deformation did not. In the case of strain aged type B steel, however, the weak cell structure was observed after dynamic deformation. It seemed to consist of the immobile dislocations which were pinned with carbon atoms by strain aging. In the case of type A steel, any difference in dislocation structure due to the strain aging effect was not observed. In order to express the mechanical behavior of Type A and B steels, the Tanimura-Mimura model was employed, and it was found that by simply taking into account the increase in quasi-static flow stress due to strain aging, flow stresses of both steels during subsequent dynamic loading were successfully described.

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3D CAD was originally developed not for drawing but for observing the shape of a 3D object. Accordingly, it is easy to construct a 3D body using 3D CAD, whereas 3D CAD sometimes leads unexpected printing of the measure of the body on the drawing sheets. Detailed information on the merits and demerits of 3D CAD in its applications to graphic science and drawing however is not understood yet. The adequacy of 3D CAD to the drawing is discussed in this report.

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Recently, design of cars and household appliances has mainly been carried out using various types of 3-D CAD systems. Although the 3-D CAD is superior for presenting the shape of the object, some problems are left unsolved. For example, it is widely recognized in the mechanical design field that conversion of a 3-D image to 2-D production drawings is not always adequate because the description of the measure is sometimes inaccurate. Under these conditions, correction of the drawings should be carried out one by one. Nevertheless, the use of 3-D CAD is rapidly increasing and, accordingly, educational institutions teaching 3-D CAD are increasing year by year. This paper reports on the introduction of 3-D CAD to descriptive geometry field. The objective of the present study is to improve the above-mentioned shortcoming of 3-D CAD on the measure description. Many kinds of problems encountered in descriptive geometry are solved using 3-D CAD.

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