Hajime Aoyama

Development of Mine Detection Robot System

The Mine Detection Robot supports the mine removal work in countries where mines are buried, such as Afghanistan. The development started from September, 2003. Considering running on rough terrains, the robot has four crawlers, and hydraulic motors in front and rear were serially connected by piping so that they could rotate synchronously. Two work arms were mounted on the robot, one was a horizontal multi-joint SCARA type with motorized 2-link arm, while the other was a vertical multi-joint manipulator with 6 degrees of freedom. Also, domestic evaluation tests were carried out from February to March, 2005, followed by overseas validation tests in Croatia from February to March, 2006. These tests were conducted with a mine detecting senor mounted on the Robot, and the detection performance was evaluated by its mine detection rate.

Decontamination robot for tritiated contaminants

ABSTRACT For a routine cleaning and a primary decontamination of tritiated contaminants in the case of decommissioning, a decontamination robot based on dry method utilizing ozone gas treatment was developed. The robot sized of 720(W)x850(D)x1,050(H) mm with a remote and automatic system consists mainly of 5 different part, a flat decontamination port of about 1,000 cm2 for ozone gas exposure with a heater and surrounding rubber curtain to isolate the inside circumstance, an ozone gas generator utilizing creeping discharge method, a gas cooler for the hot air containing tritiated vapor to be trapped, an adsorption vessel packing molecular-sieves for tritium trap, and a circulation pump. The amount of suction air is larger than that of the exposure air, therefore, non of the contaminants are scattered out from the adsorption port, and this is one of the main characteristic of the robot.

Development of a New Turbidity Sensor System Based on the Human Sense

A new turbidity sensor system was developed. The system consists of CCD cameras, a microscope, image processors and computers. It measures the mean brightness of turbid water and the mean diameter of suspended matter in the water by processing images captured by the CCD cameras, and employs Fuzzy reasoning to produce a sensory turbidity index from the mean brightness and the mean diameter. A set of Fuzzy rules was developed based on our findings on the human sense of water turbidity; 1) the brightness of the water and the size of the suspended matter mainly govern the human sense of turbidity, 2) the brighter the water is, the more turbidity humans sense, 3) the smaller the size of the matter is, the clearer humans think the water is, 4) humans show a sense of turbidity only when the size of the matter is between 0.2μm and 25∼30μm. Magnitude estimation was used to determine parameters for the Fuzzy rules. We have verified that the output of the developed sensor system shows good correspondence with the human sense of turbidity observed by the method of paired comparisons of turbid water.