We analyzed changes in apparent diffusion coefficient (ADC) during the cardiac cycle of the brain using bulk-motion-compensated diffusion imaging. ADC changes during the cardiac cycle were predominantly caused by water molecule fluctuations due to brain pulsation rather than the bulk motion of the brain parenchyma.
We developed a power assist mechanism attached to the upper limb, using differential gears. It is being developed for nurses who care an old person being bed ridden, or workers who often lift loads up and down. 2 motors behind shoulder provide motive power to drive shoulder joint and elbow joint, and differential gear makes it possible to divide the power between them effectively. Differential gear system can realize the concentrated drive system, which can reduce the load of shoulder or elbow, comparing to the distinct power motor system attach on each joint. Also, differential gear reduces backlash. We designed the mechanism can assist by 8kg with arms straightened forward horizontally. Experimental result shows the good characteristics following to the angle target.
Guide-Dog Robot which includes moving mechanism, detection and avoidance of obstacles, and human-machine interface functions is being developed for a visual impairment person. A stereo method is verified as a device to detect a pole-shape obstacle and expand to a bar-shape obstacle under in-house condition. Robot can estimate a coordinate of the obstacle using the information by the stereo method. To avoid them and go to a temporary target without any land mark, we propose two kinds of potential function and an additional potential of a person. Then, we can show arrival to the target without any troubles by using prototype robot.
We are currently developing a Guide-Dog Robot for visually-handicapped person. In our concept, the robot should have a movable platform, human-machine interface and capability of avoiding obstacles. For leading them safely, the robot is required to detect their position correctly. At the same time, it is required to detect a direction that people are walking. In this paper, the algorithm for a human-machine interface to lead the people is proposed. Getting the position data of a person as follower into account would be considered by this algorithm. To realize such an intelligent leading, we propose the new algorithm that a robot detects the center of corridor and foot of the follower simultaneously with a laser range finder (LRF). Also, the prototype robot is verified that it can lead a person successfully and safely.
This paper presents a new method of feature extraction and segmentation using near-infrared hyperspectral imaging camera. Hyperspectral imaging is a combination of digital imaging and spectroscopy. Hyperspectral imaging has been applied in the fields of remote sensing, agriculture, biological engineering and so on. The process of extracting effective information from the hyperspectral imaging data is required to automatic analysis method. In this paper, the hyperspectral imaging data segmentation method extracted the feature of the data based on principle component analysis (PCA) and K-means clustering are proposed. The proposed method is applied to the four evaluation experiment; (A) discrimination between fatty meat and lean meat, (B) discrimination between meat and flour, (C) classification of low oxygen environment and (D) classification of mouse organs. The results show the proposed method can select characteristic bands in the near-infrared range automatically. The proposed method is expected to be applied to other field.
A conceptual Guide-Dog Robot prototype to lead and to recognize a visually-handicapped person is developed and discussed in this paper. Key design features of the robot include a movable platform, human-machine interface, and capability of avoiding obstacles. A novel algorithm enabling the robot to recognize its follower's locomotion as well to detect the center of corridor is proposed and implemented in the robot's human-machine interface. It is demonstrated that using the proposed novel leading and detecting algorithm along with a rapid scanning laser range finder (LRF) sensor, the robot is able to successfully and effectively lead a human walking in corridor without running into obstacles such as trash boxes or adjacent walking persons. Position and trajectory of the robot leading a human maneuvering in common corridor environment are measured by an independent LRF observer. The measured data suggest that the proposed algorithms are effective to enable the robot to detect center of the corridor and position of its follower correctly.
We developed a power assist machine attached to the upper limb, using differential gears for nurses who care an old person being bed ridden, or workers who often lift loads up and down. Two motors behind the shoulder of the equipped person provide motive power to drive shoulder and elbow joints, and the differential gear makes it possible to divide the power between them effectively. This differential gear system can reduce the backlash of gears. The five degrees of freedom of shoulder blade motion were taken into account with the shoulder-joint link mechanism. Furthermore, to grasp the behavior of the arms of the equipped person, pressure sensors were attached under the upper and lower arms. As a result of the experiment wearing the machine, the arms of equipped person could fluctuate at will.
We developed a power assist machine attached to the upper limb, using differential gears for nurses who care an old person being bed ridden, or workers who often lift loads up and down. Two motors behind the shoulder of the equipped person provide motive power to drive shoulder and elbow joints, and the differential gear makes it possible to divide the power between them effectively. This differential gear system can reduce the backlash of gears. The five degrees of freedom of shoulder blade motion were taken into account with the shoulder-joint link mechanism. Furthermore, to grasp the behavior of the arms of the equipped person, pressure sensors were attached under the upper and lower arms. As a result of the experiment wearing the machine, the arms of equipped person could fluctuate at will.
