The force plate is widely used in the rehabilitation center and the hospital for the motion analysis or the evaluation of the artificial leg. However, the commercially available force plate is too costly to be installed in all the establishment where has need of it. In this study, a simplified large size force plate for gait analysis on the level ground, the slope and the step is developed. In this force plate, we use the shear beam type load cell to avoid the measurement error by the position of load cells. In addition, it is possible to analyze the motion of gait on the slope and the stairs by mounting the slope model or the stairs model on the force plate for the level walking. By using the force plate developed in this study, the gait analyses on the level ground, the slope and the stairs are made. The characteristic patterns of the floor reaction forces are observed in the gait analyses on the slope and the stairs. The force plate developed in this study can be used for multipurpose gait analysis on the level ground, slope and stairs.

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   Plastic ankle-foot orthoses are used as effective braces for hemiplegic patients. However, few studies have investigated the mechanical properties derived from the orthoses themselves due to the difficulty in investigating PAFO’s loading condition using sensors which are suitable for orthoses. In a prior study, we developed the mechanical measuring system that included a 6-axes force-torque sensor embedded in the orthosis and analyzed the ambulatory data of healthy subjects using this orthosis. The present study uses the same system to evaluate the ambulatory data of two hemiplegic patients and compares the results with data obtained from healthy subjects.

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   Three-Dimensional CAD software represents parts as trees as specification trees of feature commands used in modelling procedures. In order to utilize the vast amount of three-dimensional models that have already been created, a method for combining shapes is required. This paper presents a simple system for taking tree representations of shapes and combining them to create new shapes. The method is based on an evolutionary algorithm with modifies the structures of trees. An experimental software system is constructed and various parameters are determined from design experience.

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   A control method of mobile manipulation for a humanoid robot, mobile manipulation means the integrated motion centered on arm's manipulation, is discussed. This method makes the arms carry out the manipulation, and the legs assist manipulation by adjusting its motion in order to keep arm's manipulability high. Firstly, the arm tips always follow their desired position under the condition with external force by impedance control. Secondly, the shoulder is controlled so that manipulability and stability can be improved. Moreover, we define three functions; they are an average of manipulability measure, and an average and a minimum of stability margin in a locomotion cycle. We utilize their values in a locomotion cycle rather than the values of them at every moment, because manipulability and stability vary with robot motion. Then, we define total evaluation function which consists of the sum of them. Step length and timing of step motion are controlled so that the function can be optimized. The effectiveness of the proposed method is ascertained through the computer simulations.

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   Spinal cord injury patients are easy to become the obesity because of insufficient movement. The ratio of the obesity complication of the spinal cord injury person is bigger than that of the healthy subject. Therefore the importance of body fat measurement of the spinal cord injury patient is very high for their health maintenances. The body fat measuring instrument is available on the home as an index to physical fitness and health care reinforcement. Portable body fat measuring instrument with bioelectrical impedance method is used for spinal cord injury patient in the hospital from the viewpoint of obesity prevention. However, the discrepancy of percent fat mass result is reported between bioelectrical impedance method and dual energy X-ray absorptiometry. In this paper, it was found that the body posture greatly affect the percent body fat of the spinal cord injury patients. Moreover, estimating method of percent fat mass is proposed for spinal cord injury patient.

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   Many industrial structures are built under complex loads. Some irregular loads cause cracks or defects in the structure. Then fatigue causes crack growth from these cracks under mixed mode. The condition of these crack tips turn to mode I domination by crack growth. Because general fatigue crack growth is progressed under mode I domination, mode I fatigue crack growth rule had been derived by many researches. However, a fatigue crack growth rule under mixed mode has not been established. Measurement of crack growth from irregular initial crack is difficult.
   In this study, crack growth experiments are operated to obtain basic data for fatigue crack growth under mixed mode. Slanted cracks are installed in three point bending specimens. Crack growth tests are demonstrated for some slant angle. Mixed mode condition is caused at the front of the slant crack. Crack growth rate, fracture path and others are discussed as these experimental results.

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   The optimal configuration and joint torque distribution of a humanoid robot for generating desired force at its hands is discussed. The robot is required to stand stably and to support the force and its weight under the constraint of maximum joint torques. Furthermore, it is important to keep the robot controllable against sudden change in the force. From this point of view, an evaluation function for generating large force based on statics is proposed; we focus jacobian matrices of two arms and legs to give the robot adaptability to force change. Then the method of obtaining the optimal configuration, footholds and joint torques of the robot is described. The effects of the method are verified through computer simulations.

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   Electrical resistance tomography method has been applied to the real-time measurement of cross sectional distribution of the erythrocyte sedimentation by measuring the electrical properties of blood. The electrical conductivity distribution was observed at three distinct planes from top to bottom of a container. In the experiments conducted with bovine blood, the average relative conductivity increased at the top and middle of a container with time while the average conductivity decreased at the bottom of the container. Moreover, the distribution of the conductivity at the middle of the container was peculiar. The conductivity was lower in the center of the cylinder, and gradual increment was observed towards the cylinder wall. The conductivity values were then interpreted in terms of concentration and orientation of the red blood cells based on Maxwell-Fricke equation. The concentration variation and different orientation of the red blood cells at different planes from top to bottom are expected to shed light on the mechanism of erythrocytes sedimentation.

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   The sizes of buildings have been computed from two photographs from different directions. By conducting an inverse perspective transformation, a three dimensional representation of a building can be obtained. Unfortunately, there are cases where only one photograph of the scene is remaining. This is the case when we reconstruct the buildings from landscape from back in the past from an old photograph. By combining map information with photographs, we have proposed a method for obtaining the size of buildings. Using AutoCAD and geometric construction methods, we show that reconstruction can be done accurately. The case where trees and other buildings obstruct the view are also addressed.

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