Success in Testing AHS on Public Road

A large scale test, the first of its kind in the world

 AHS is deemed the system with the highest level of technology among ITS technologies. Expectations are high for such potential benefits as a reduced operating burden on drivers through automation, improved safety by eliminating the possibility of accidents, and social and economical contributions created by improved transportation efficiency; these are some of the highly prized characteristics of the system.
The Ministry of Construction has been jointly working on the research and development of AHS with 25 private corporations. Experimental tests open to the public were held on the almost 2 mile test course on the premises of its Public Works Research Institute in November 1995 using 3 vehicles.
In addition, practical tests were carried out on a much larger scale along a 7 mile stretch between the Komoro Interchange and the Tobu Yunomaru Interchange on the Joshinetsu Expressway, which was slated to be opened soon for public use, on September 19. It is the first of such tests to be run on a public road in Japan, and the world's largest in scale using 11 cars running in a series over such a long distance.		 　　 AHS
Automated driving test using public road shortly before it is open for public use. LCX is installed on the other side of the car.

Much smoother operation than actually expected

Many positive comments were voiced by observers from the media and researchers who were invited to ride in the tests cars. This included the Construction Minister, who was quite impressed.
The course was provided with magnetic nails buried in the ground along the expressway at 6.6 feet intervals together with an LCX cable laid along the entire length. The course was also equipped with television cameras and other devices for collecting and processing information. The tests consisted of:

  1. Rear-end collision prevention tests: With information provided from LCX cables, an alarm is given to the driver if the car comes close to a car in front, and it automatically applies the brakes if necessary.
  2. Lateral collision prevention test:
    The system measures the distance between other cars running alongside and to roadside objects, and it warns the driver with an alarm if the distance becomes critical, automatically steering the car away from the object, if necessary.
  3. Detection tests for obstacles in the car's path:
    The image sensor installed on the roadside instantly detects any obstruction created or developed in front of the car due to an accident or any other reason, and it warns the driver through the LCX cables.
  4. Automated driving test:
    The car is automatically operated as directed by signals and information sent from the LCX cables and collected by the onboard radar.
 　　 AHS test
Experimenting with the frontal obstruction detecting function


Tests were repeated at the intervals of 3.1 miles - The safe driving system

The experimental driving tests were conducted in the following way along the course. The safe driving system tests from @ through B were repeated at 3.1 mile intervals to accumulate data for future research and development:


    １、 Experimental test of the rear-end collision prevention function ( from the start to the 2.5 mile point ) :
    - Automatic deceleration by releasing the accelerator pedal:
    The car is set to run at a distance of 130 feet from a car traveling in front of it. When the car in front decelerates slowly from 44 mph to 38 mph, the trailing car will automatically slow down by adjusting the accelerator pedal so as to maintain the 130 foot interval between them.
    - Deceleration by actuating the brakes:
    The car is set to run at a distance of 130 feet behind a car running in front of it. When the car in front decelerates slowly from 44 mph to 38mph, the trailing car will automatically slow down by braking so as to maintain the 130 foot interval.
    - Stopping by applying the brakes:
    The car automatically decelerates from the speed of 38 mph by using on-board radar to detect an immobile car ahead of it at a distance 330 feet.

    ２、 Experimental test of the lateral collision prevention function ( 2.5 and 2.8 mile points ) :
    If the car leaves its lane because of improper steering, the relative position of the car in relation to the lane is detected by the magnetic nail sensors and the driver is warned if it moves more than 3 feet from the line of magnetic nails.

    ３、Experimental test of the frontal obstruction detecting function ( 2.8 and 3.1 mile points) :
    The image sensor detects an immobile car ahead and transmits a warning signal through the LCX cables to the car. The system gives the driver both an audio warning and a visual warning on the CRT screen.

　　 AHS test
Automated platooning operation
test using 11 cars


On the leading edge of AHS development
　The automated driving function was tested over the entire stretch of the road:



AHS
（１）Information Processing Device
Prepares information for vehicles and processes information from vehicles.
（２）LCX
 Transmits indicated speed and information on accidents to vehicles. Transmits information from vehicles to information processing device.
（３）CCD Camera
 Measures distances between a car and the car in front of it, and between a car and the white lines on the road.。
（４）Antenna, Communication Equipment
Receives information from LCX, and transmits information about vehicles (accidents, breakdowns and so on) to LCX.
（５）Information Gathering Device
Detects occurrences on the road and transmits information about them to a processing device.
 　 （６）Information Processing Device
Decides what measures to take to control the car based on the information from LCX, radar and magnetic nails.
（７）Radar
 Measures distance between a car and the car in front of it, and detects obstacles on roads.
（８）Magnetic Nail
 Sends magnetic signals to guide vehicles to remain within the lane.
（９）Magnetic Nail Sensor
Detects magnetic signals.
（１０）Vehicle Control Device
Accelerator Actuator / Steering Actuator / Brake Actuator / Controls steering, braking and so forth.
（１１）Information Display Device
Transmits information on accidents, warnings and so forth to drivers.

The birth of AHS Research Association

 The Technical Research Association:
Road Transport Support System Development Organization (AHS Research Association) was established on September 25, 1996. The objective of the organization is to promote cooperation among corporations of various industries for research and development related to road systems in order to put AHS into practical use.

The main subjects of the intended research and development are:
　(1) Study of the concept of AHS.
　(2) Study of road systems for collecting and processing road information.
　(3) Study of road systems for controlling running vehicles.
　(4) Study of road systems utilizing state-of-the-art communication systems.
　(5) Verification tests of road systems.

　The period of research and development extends over 5 years, from the current fiscal year to the year 2000, with participation from the 21 corporations listed below:
Denso Corporation, Fujitsu Ltd., Hitachi Cable, Ltd., Hitachi,Ltd., Honda Motor Co.,Ltd., Ishikawajima-Harima Heavy Industries Co., Ltd., Isuzu Motors Ltd., Matsushita Electric Industrial Co.,Ltd., Mazda Motor Corporation, Mitsubishi Electric Corporation, Mitsubishi Heavy Industries,Ltd., Mitsubishi Motors Corporation, NEC Corporation, Nippon Telegraph and Telephone Corporation (NTT), Nissan Motor Co.,Ltd., Oki Electric Industry Co.,Ltd., Omron Corporation, Sumitomo Electric Industries, Ltd., The Furukawa Electric Co.,Ltd., Toshiba Corporation, and Toyota Motor Corporation (In alphabetical order).





　

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