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A new concept for communication for platooning of leader-follower vehicles is presented. The leader vehicle is equipped by a omni directional camera and laser radar. The omni directional camera can capture a omni directional views and the view information is used to autonomously control the leader vehicle. The laser radar set to the rear part of the leader vehicle detects the relative distance and angle of the follower vehicle. By the information of the relative position and angle of the follower vehicle, control instructions are generated and sent via vehicle-to-vehicle communication between the leader vehicle and the follower vehicle.

The sensing and control scheme of autonomous vehicle, learned from the human driving is considered. To implement human driving manners, we imitate “characteristics of the human eye” and “human driving rules extracted from driver’s feeling”. Following two approaches are considered; 1. Reduction of image processing load of FFT picture compression technique by the manner of human eye sensitivity. 2. Simplified driving rules extracted from the human driving manner correspond to the energy minimum optimal control.

This paper proposes how to develop an autonomous vehicle for factory and/or storehouse use. Where the geometric arrangement changes frequently due to the turnover of the cargo. We apply the sensor fusion technique by use of the Omni directional image sensor and laser radar generate the map of such situations. We propose a new update algorithm called SMT (Shift Matching Transform) that obtains region segments with trusted semi-real-time geometric map. We demonstrate how to determined the absolute position of the vehicle by the position information of arbitrary wall. Experimental results on the corridor, Shows the semi-real-time map reconstruction with enough validity.

The project of the ITS (Intelligent Transport Systems) has been actively promoted researches and developments for the safe and efficient traffic. In the project, development of the lane detection algorithm is indispensable. Under outdoor environment, it is very difficult to detect a lane and to distinguish the various obstacles by vision systems, due to optical problems. Here we propose the Active Contour Model Method, which is known as the most robust method to detect the lane contour. The vehicle based on an electric wheelchair for handicapped persons was used to examine the validity of the method.

The electronic sound is used as one of the very common means of human-machine interface. Few investigations of how human feels to such the simple sounds noisy or comfortable, exist. The electronic sound must be designed by considering how or in what situation it is used. This research is aimed at investigating how human feels to a variety of electronic sound and describes the relation between human feeling and physical characteristics of sound. We investigated how physical parameters of sound effect to the human feeling via evaluation experiments. We found relations between the human auditory feeling and the physical characteristics of the sound. We showed a guideline of how to design a variety of electronic sound that satisfy the given human feeling specifications.

An automatically guided vehicle by vision that recognizes the two white guidelines has been developed. The vehicle can run on a mildly bumpy grass course like as golf course up to 3 km/hour, staying in between two white lines with span of 3m to 3.6m avoiding obstacles within lanes. In this paper, the construction of the vehicle, the sensing strategy, the control algorithm, as well as practical aspects of the implementation are described. Employment of 1D image sensor which detects two white lanes yields the remarkable feature of the proposed system. The advantage of 1-D image sensor is the simplicity as well as significant reduction of the task for image processing in comparison with the conventional 2D-camera vision. Through the actual experiments at International Ground Robotics Competition '97, which held at Oakland University in June, we demonstrated the superior performance compared with conventional 2D vision type vehicles.

The airbag systems in the first generation had been developed and are equipped in real automobiles. This paper is aimed at describing a new airbag scheme that might be categorized in the 1.5 generation. The airbag system always needs some delay time between the triggering and complete expanding. The existence of the delay time is the main cause of difficulty for accurate airbag triggering. The predictive airbag expanding algorithm that compensates the delay time was proposed and the validity was examined in the first generation development. Development of the 1.5 generation airbag systems with the higher performance are our next problem. Airbag equipped in automobiles must receive driver's body at the optimal timing when collision by which the effect of airbag is extremely improved. The more accurate predictive airbag system is required.

This paper describes the accurate and detailed estimation of traffic conditions around our vehicle on road by the incomplete laser radar signals. The conventional laser radar system monitors only one vehicle that runs just in front of the our vehicle. Careful observation of the laser radar signals includes more information than that required. This research aims at developing a new traffic condition monitoring system that monitors 8 to 10 vehicles that run around our vehicle by fully using the signals from the radar.

Comfortable man-machine interfaces are required for current advanced vehicle systems. This paper aims at investigating the relation between reaction force of switches and human switch operation feeling. We investigate how each reaction force of switches effects the touch feeling of switches via sensory test. The results of factor analysis for the questionnaire data obtained in the sensory test show that the most substantial factor is the feeling expressed by the words “Clear”, “Smooth”, “Stiff”, and “Clicking”. Finally, each feeling described by each word is directly evaluated by reaction force or vice versa on dual scales. The dual scale for reaction forces and degree of feeling can be directly used for designing comfortable switch.

The advanced safe driving of vehicles have fully depended on the development of the safe driving systems. The final strategy must take the drivers skill into account. This paper describes a method to detect and evaluate driving skill. We present a new system to measure the curvature of driving loci against the distance by using speed and rate gyro sensors and present a method to extract the driving curvature from that of road itself. It includes the information of drivers' skill by which the driving conditions can be evaluated.

An airbag upon collision of automobiles must finish expanding at the time when the driver's body arrives at the surface of the expanded airbag from the normal position and it must receive the body softly. Either early or late expansion reduce the effect. Determination of the optimal timing for trigger the airbag is quite important. But it is a difficult job, due to the time delay in the bag filling with the gas after collision. This paper focuses on the issue of the airbag technology to how to find the optimal trigger timing and presents a new and straightforward algorithm to determine the timing by introducing the concept of the prediction. The algorithm first predicts how the driver's body will move in the future time for a time equivalent to the delay time and triggers the airbag by the predicted information so that it can compensate the delay by the airbag operation.

This paper describes a new type of absolute speedometer of automobiles. It is known that the electric field intensity of the radio waves in the UHF/VHF range exhibits spatial periodic patterns due to the multi-pass fading phenomenon. We employ this pattern as the spatial scale for speed measurement. In this method, first two antennae set at the front and rear site of vehicle detects the pattern. Next a micro processor estimate the speed by calculating delay time between the two patterns detected. We have examined if the pattern can be used as the spatial scale for speed measurement by laboratory experiments. We found it could1). In this paper we consider how to realize an automobile speedometer based on the above idea.

Accurate information of the absolute speed of a vehicle, when available, can be vital in simplifying the control laws of an anti-lock braking system (ABS) and auto-traction system (ATS). A current meter for measuring the speed of a vehicle is to multiply the measured wheel rotation rate to the wheel radius. The approach often includes abrupt unpredictable errors due to slip and skid of wheels and a biased error due to the steady state slip. These errors are sources of difficulty in the implementation of an ABS that is based on the absolute speed of the vehicle. This paper describes an accurate rule-based Kalman filtering technique for estimating the absolute speed of a vehicle. The enhanced accuracy is achieved by employing an additional accelerometer to complement the wheel speed-based speedometer. The accelerometer measures the acceleration of the vehicle in its forward direction and may be corrupted as well by high frequency noise.

This paper describes a new method of measuring the absolute speed of moving objects such as people who are walking or running, running animals, vehicles, sailing boats and the like. The method estimates speed using the time delay between spatial values (patterns) detected by the front and rear sensors which are separately disposed on an object and aligned in the direction of movement. It is known that the electric field intensity of radio waves in the VHF/UHF range exhibit a spatial periodic pattern due to the multi-pass fading phenomenon. It is also known that this phenomenon is a source of noise in automotive telecommunications. In experiments we make use this pattern for speed measurement and investigate if the pattern can be used to provide a spatial value which permits the estimation of the speed of the above mentioned types of objects.

This paper describes how to realize an accurate, compact, and economical fuel gauge by the pneumatic method for deformed and flexible tanks which shake and vibrate, whose attitude changes and in which liquid sloshes and the temperature changes. The basic concept employed in the pneumatic method involves the use of the ideal gas law. The volume of liquid in a closed tank can be obtained by subtracting the volume of gas in the tank from the tank capacity. To determine the gas volume, both a reference tank attached to the main tank and the main tank were subject to the sinusoidal displacement. From the equations based on the dynamics of the pressure in the main tank derived from the ideal gas law and flow of gas thought a pipe, relations were obtained that gave the gas volume in the main tank from the filter pressure signals in the both tanks.

This paper describes how to directly and accurately measure liquid volume in a deformed tank which has gas-leaking pinholes, whose attitude changes and walls vibrate, and in which liquid sloshes. The proposed method is different from conventional methods that use level meters, and makes the measurement possible without setting level detecting devices such as a float in the tank. The method makes use of Boyle's law, and the measurement procedure is as follows: (a) first, we determine the volume of gas in the tank by measuring gage pressure increased by compressing the volume of gas in the tank, and (b) next, we find the volume of liquid by subtracting the volume of gas from capacity of the tank. This demonstrates that one standard measurement system can be applied to a variety of tanks with a certain range of volume capacities, whereas conventional methods using level meters require designing and manufacturing different detecting devices depending on the shapes of the tank.