As for the visual sensor of Robots, especially for the mobile Robots, the function to aquire a three dimensional information of the environment is crucial, and a range finder which directly measures the range information with active scan of the laser beam will be widely used in future. This paper firstly takes the standpoint that the range finder is realizable, and discusses some of the basic problems of the signal processing of the range finder especially when it is used as a map realization system of terrain for mobile Robots. The paper derived following results: (1) The reflected point of the laser beam on the surface of the terrain are radially distributed and thus a specialized method can be introduced for the interpolation of the beam points. A method named Radial B-spline interpolation is proposed for this end. By separating and applying special processing method in shadow region, better result of the interpolation can be aquired. (2) An interpolation method which associatively use the memorized information is shown feasible for signal processing of the range for terrain. The method to memorize the terrain, or the method to associatively apply the memory for new scene is shown appropriate from computer simulation, and further improvement of the estimation results are demonstrated. The paper also stressed the importance of the development of the hardware of the laser beam range finder system and further consideration on, so to speak, intelligent signal processing method for the range finder.

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A compact crawler vehicle for a mobile robot has been developed, which has active adaptability to terrain variations and is able to pass over obstacles and go up and down stairways. The track of this crawler is supported by 3 wheels. Two of them are mounted on the side of the body, but the other, called a planet wheel, is supported by main and sub arms, and is able to change its position in order to alter the crawler shape as contoured by the track. This transformable capability produces many terrain adaptability functions, for example, adjustment of attack angle, reduction of vehicle length, elongation of ground contact length, and tilting the body forward and backward.
If diameters of the 3 wheels are equal in size, the planet wheel must travel in an elliptical orbit in order to maintain track tautness. If the rotational angles of the main and sub arms are controlled to be always equal in size and different in direction, the planet wheel is kept in the elliptical orbit. The relation between these angles is achieved, and is always assured by, a simple synchronizing mechanism. Therefore, the control of the crawler shape is extremely easy and only requires controlling the rotational angle of the main arm.
This vehicle has only three degrees of freedom. If we define adaptability coefficient as the number of adaptability functions divided by degrees of freedom, the value of this vehicle is 1.67.The va ue is larger than that of a 4 tracked vehicle which has more adaptability functions. This vehicle can pass over obstacles and go up and down stairs autonomously with its micro-computer controlled through touch sensors mounted in front of and under the body.

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Here presented is an experimental system of a kind of on-board location and guidance system controlled by dead-reckoning computer with route setting system in the computer memory. The location and heading of the roboted vehicle are essentially computed from the rotation of both wheels.
The steering system is operated by comparing the predicted position, which is computed using the data of location, heading and velocity, with the route in memory. The experimental results using a small battery cart show the good accuracy and good performance of this system.

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It has been expected for a long time to be developed a robot to work on the vertical wall of tall buildings, side wall of large ships and so on.
Forces produced by magnetism and low pressure of air sucking to the fan are available to sustain the robot on the vertical wall, and the wheels, crawlers and some other walking mechanisms can be used as the methods of moving. A good many machines are able to build by combining these mechanisms for various applications.
Two kinds of robot models were built and tested. Air was sucked from the peripheral nozzle of the suction surface to the fan and the crawlers were used as a moving system. They have two dangerous situations of falling and slipping, and the limitations of them are determined. It is also important to decrease a shock of collision by a falling mass in practical use. In such a case a damper composed of a spring and dashpot is usable. The optimum design condition of it is derived for a given condition.
To study the matching of aerodynamic characteristics between a suction surface and a fan is important to understand the safety conditions of this type robot and to design an active controller to avoid the danger of falling, and it is done for an above model as an example.

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This paper presents a navigation method which enables a mobile robot to perform autonomous locomotion. And the feasibility of this method was demonstrated using experimental hardware, a prototype robot with ultrasonic sensors.
This method uses simple shaped objects, such as poles and flat surfaces of walls selected from the environment, as landmarks and a map indicating the relations of these landmarks. The robot moves from a given point to another along a' designed path using its own sensors. At each point it meas-ures the position of natural objects selected as landmarks and corrects its path.
The basic problems encountered in realizing this method are discussed. They are path design which connects two points in the environment, control of a mobile robot to move along its path, measurement of objects' positions using an ultrasonic sensor and correction of error from its designed path.
A basic technique necessary to navigate a mobile robot is the ability to control it so that it follows a designed path accurately. Because of the lack of absolute position information, a mobile robot needs to get accurate position data from its surroundings. This method uses natural objects to gain such information. And it has the merits that it can reduce the equipment investment to the environment to supply position data and that it can simplify the object detection problem by giving information about objects.

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In Japan, at present the number of severely crippled and bedridden patients who have to be completely taken care of in daily life is tending to increase for several reasons, and in addition proportion of aged persons in the population is growing.
Providing care for these persons is becoming an extremely serious social and economic problem.
In order to reduce burdens imposed upon the handicapped persons and those responsible for their care and nursing, we have undertaken research upon the development of a four wheel mobile robot system to provide assistance in the daily activities of bedridden handicapped persons.
The characteristics of this system are (1) front wheel power steering and independently directly driven rear wheels, (2) one pair of manipulators which have nine degree of freedom mounted on the four wheel mobile device, (3) a hierarchical control system with one 16 bit and several 8 bit microcomputers, and we utilize a teaching-playback method to develop control programs for specific activities.
As a result of our research and development, we have succeeded in establishing fundamental techniques for mobile robot systems for bedridden patients.

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An Automated Vehicle Robot has been developed for inspection for various components inside primary containment vessel with supported by Japanese Ministry of International Trade and Industries (MITT) . The Inspection Robot consists of; a floor-moving vehicle with four crawlers; TV cameras for inspection and operation; detectors and sensors; multi-joint arm mechanism for TV camera; a signal transmitter; cable handling device.
In this paper the authors discribe about the crawler type vehicle. This vehicle is developed for moving smoothly in Nuclear Power Plants. This vehicle has two steering mechanism in front and rear, and has wheelbase chaging mechanism at the center of the body. With these mechanism, this vehicle can climb up 45°-stairs (a step height; 220mm) and can rotate with short radius. The crawler type vehicle satisfied the design conditions, and system tests for inspection are now under going.

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Locomotion on the uneven floor which is typicaly located in the nuclear power plants is a very interesting matters, so, many works have recently been conducted.
Since crawlers are used for the typical locomotion method, for the first step, we have evaluated the principle movement of crawler through several kinds of experiments. And we have propsed a new type vehicle. This vehicle has four legs with two jnints, two driving wheels under the body and four drive supporting wheels at the end of each legs. It has accomplished not only high mobility on the flat floor by driving wheels but also high stability on the uneven floor by walking, as well as, easy control by creeping mode locomotion. We have already done basic experiments and are conduct-ing to improve the reliability which is supported by sensors and its intelligent application.

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An experimental robotic remote handling device is described which has been constructed in order to investigate various engineering problems in advanced remote handling such as man-machine interface, system control, and communication. The device consists of a mobile station and a control station. The mobile station comprises an electrical manipulator having seven degrees of freedom, a TV camera, a control sub-computer, a servo-control unit, radio transmitters and receivers, batteries, etc. which are mounted on a crawler-type vehicle. The control station is equipped with a master-arm of the manipulator, radio transmitters, receivers, a TV monitor, a main control computer and its peripheral devices, etc. The manipulator can be operated in either master-slave, playback or programmed control mode with the assistance of the control computer. The communication between the mobile and the control stations is made using optical fibers or radio link.

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