Technologies in mechanical engineering necessary for a development of clinical automatic analyzers are reported. Since the automatic analyzers, which have been indispensable for the current medical treatments, have the purpose of developments which requires smaller sample consumption, and higher accuracy and higher speed analysis, the roll of mechanical engineering has become important. Moreover, the developments of the miniaturized analyzers have been accelerated, because DNA diagnostics will be practically utilized in the near future. The extensive and urgent studies of mechanical engineering in micro scales are desired.

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A novel probe for local elasticity measurement of soft biological tissues was developed. In this probe, specimen surface was aspirated through a hole at the probe end to obtain its aspiration pressure-specimen deformation relationship. Young's modulus of the specimen was calculated by comparing the curve with the similar relationship obtained from a finite element analysis. The specimen deformation was measured with a laser displacement meter, which enabled us to make the aspiration hole smaller and to reduce the number of components of the measurement system. We measured Young's modulus of a human finger skin with the probe to find that the modulus decreased with the hydration of the skin. The probe was able to detect subtle change in the epidermis induced with the hydration. It would become a powerful tool for the noninvasive measurement of the skin elasticity.

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A practical simple control design method for the motion control of pneumatic systems is proposed. The proposed control is robust for the change of a plumbing route from the control valve to the pneumatic actuator. That leads to much smaller magnitude of the din and vibration that are generated by control valves. It means that the proposed pneumatic servo systems can be used as an actuator of the equipments that used in a medical and welfare facilities. The experimental results are shown to confirm the effectiveness of the proposed design scheme.

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Subjective evaluation of riding comfort during ambulance transportation is discussed. Putting on the brake during ambulance transport generates foot-to-head acceleration of the patient for several seconds and causes the rise of the blood pressure at his head. Moreover, frequent change of the foot-to-head acceleration will cause motion sickness and vomiting in some cases. There is, therefore, a possibility that foot-to-head acceleration aggravates the patient's condition. Rapid acceleration and sudden stop are frequently performed to evaluate subjects' riding comfort by using semantic differential method. A conventional stretcher and an actively controlled stretcher which absorbs the foot-to-head acceleration by changing the angle of the stretcher and adding the gravity to the patient are used. The experimental results show that the riding comfort of the ACS is better than that of the conventional stretcher.

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As one of the minimally invasive therapies of renal and urethral calculi (kidney stones and urethral stones) extracorporeal shock wave lithotripsy (ESWL) is now widely used instead of open surgeries. To ensure the safety of the therapy, it is thought to be important that the stone must be correctly positioned at the focus point of the ESWL instrument. If the positioning is incorrect, normal renal tissues may be harmed. Some of the damage to the tissue (side effects) is reversible, but the rest are irreversible. Hitherto positioning is done before and during the procedure using X-ray or ultrasound. But it is not always effective since the stone in the body changes its position. We noticed that the movement of the calculi 9stones) is caused by breathing. Therefore in this study, suing a special sensor, we tried to detect whether the movement of the chest wall is proportional to the movement of the stone.

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This paper is concerned with the development of palpation sensor for detecting the prostatic cancer and hypertrophy. The sensor probe is a layered medium with polyvinylidene flouride (PVDF) films embeded in a matrix sponge rubber and placed on the tip of a driving mechanism. It is pushed onto the flexible object and oscillated at about 50Hz and peak-to-peak amplitude 2mm. The laboratory test shows that the magnitude of sensor output has a good correlation with the spring constant of the sample rubber block. Some clinical data on the stiffness of prostate glands are presented. Further, the effect of the structure of probe on the sensor output is detailed.

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This paper is concerned with the development of an artificial urethral valve for treating urinary incontinence, which is driven by the shape memory alloy actuator. A non-contact, compact induction heating system using the power transmission coils is introduced, which is consisting of the oscillation, regular voltage, amplifier and transmission circuits. It transmits the electric power to the artificial valve inside the body transcutaneously. The transformer is designed so that it is driven by the battery considering that it be used outside the buildings. From the experimental results, it is shown that the proposed transformer system driven by the battery supplies enough power to the urethral valve to open the choked urethra.

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This paper is concerned with the development of a sensor system for monitoring skin roughness. The base of the sensor is an aluminum shell, around which a sponge rubber layer, a PVDF film layer, a protective surface layer of acetate film and gauze are stacked in sequence. The sensor is attached onto the tip of an elastic cantilevered beam and pressed against a human skin surface. The beam is then slid over the sample to collect the information on the object through the sensor. The features on the data are extracted by calculating both the variance and the intensity of power in the several frequency rages. Experimental results show that the present sensor system works well as a haptic sensor for monitoring the variations of human skin conditions depending on the aging.

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The new method to deal with both range data and image data with data vagueness in sensor fusion process is proposed. Using laser range finder in this study, range data and image data are obtained. In our method, comparing range data and road model without any obstacles, the possibility index of obstacle existence is defined. Sensor fusion both range data and image data are carried out considering data vagueness. The method is tested by real data and evaluated.

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TV cameras involve some intrinsic parameters such as the image coordinates of principal point, the principal distance, and the distortion of lens. The calibration of these camera parameters is one of the most important techniques for 3D measurements based on visual information. The information derived from 2D image is visual angle, and we should evaluate the accuracy of calibration by using the visual angle. When we evaluate the accuracy of calibration based on the visual angle, which direction should we take as the reference of the visual angle? Nominal visual angles have been usually used for evaluations, that is, true values of the coordinates of the principal point have been used as the reference of the visual angle. But, in this way, the optimal setup condition of a fiducial chart varies from a camera to another, that is, the condition varies with the length of principal distance : the fiducial chart is a plane, on which fiducial marks are drawn, and is moved along the depth direction. In practical use, it makes calibration procedures troublesome, and, so, it is desired the optimal setup condition not to vary t between cameras with various principal distances. This paper proposes a novel concept of the evaluation method with the visual angle : the calibrated coordinates of principal points are taken as the references of the visual angle. We refer this angle to the effective visual angle. It yields a useful result that the optimal setup condition does not vary with the lengths of principal distance.

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This paper describes the measurement method to obtain the motor exciting foce Air-conditioning system use. One is the direct measurement method. The motor excitation force was measured using a test system with the motor and a load cell. In this method, we grasped characteristics of motor exciting force. Another one is the indirect method. The finite-element model for the motor was created, and the circumferential acceleration responce of the motor housing was calculated in loading circumferential force. One other hand, the circumferential acceleration of motor housing was measured. Using both the calculated acceleration and the measured acceleration, the motor exciting fore was estimated. An electromagnetic vibration torque is one of the circumferential force of motor. We tried to calculate the vibration torque using the equivalent circuit of the motor.

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