December 15, 1998, Tokyo: Mitsubishi Motors Corporation announces the development of a new Driver Support System (DSS) that leads the way in ITS(*1) technology. Integrating some of the latest technologies developed by the company with other well-proven components, the system comprises: (1) Lane Departure Warning (new), (2) Side-rear Monitor (new) and, (3) Preview Distance Control (introduced in January 1995, a world-first technology). The new DSS is scheduled for application in a new model to be announced in the fall of 1999.
The company has long been an industry leader in developing driver support systems that lighten vehicle operation load and compensate for driver error. It has been an active participant in the Ministry of Transport's ASV(*2) project that forms the backbone of ITS research in Japan, and in the AHS(*3) project led by the Ministry of Construction, developing innovative technology for both projects. The company was also one of the first auto makers to develop and apply technology that realizes dramatic improvements in active safety. Industry-first systems include INVECS(*4), TCL with Road Curvature Preview(*5), Preview Distance Control(*6), AYC(*7) and ASC(*8).
Features that ensure the new DSS will make a significant contribution to safer vehicle operation include: Integrated monitoring of road and traffic conditions in front of, to the side, and behind the vehicle; Easing the operational demands on the driver and; Prompting the driver to take greater care in order to avoid lapses of concentration or careless mistakes.
Mitsubishi Driver Support System
1.Lane Departure Warning System
This brand new technology is designed to both warn the driver when he begins straying from his own lane, and also to urge him to steer so that he stays in the middle of his own lane. In this way, it will help prevent the driver from drifting into an adjacent lane, from making contact with central dividing strip or other barriers, or from going off the road.
The system comprises: A miniature CCD video camera in the interior rearview mirror; Sensors that monitor vehicle status and the driver's handling actions; An audible and visual warning system that prompts the driver to be careful and; An actuator fitted to the steering column. The video camera, which serves as the main system sensor, monitors the lane division lines ahead of the vehicle.
Lane Departure Warning System
The system uses information on the lane division lines ahead of the vehicle acquired by the CDD video camera, sensor data on vehicle status and on how the driver is operating his vehicle to judge whether the vehicle has started to stray from its lane. When necessary, the system prompts the driver to be careful using audible and visual warnings and by making the steering wheel vibrate. At this time, the system encourages the driver to take corrective action by adding a steering torque that brings the vehicle back into the middle of own lane. The system leaves the driver in full control over his vehicle by ensuring the steering torque applied is not sufficient to interfere with the driver's own steering efforts, and by disengaging the system when the driver uses his turn indicators to signal a change in vehicle direction, or when he turns the steering wheel in an emergency evasive maneuver.
Vibrating the steering wheel reduces the time required for the driver to start making a corrective steering action, compared with an audible warning only. And the application of a corrective steering torque that directs the vehicle towards the middle of its own lane makes it possible to reduce response time further still. With its steering torque information feature, the Lane Departure Warning System gives the driver more time to take corrective or evasive action when his vehicle starts to stray out of its own lane because he has taken his eyes off the road ahead, or other reasons.
Employing video cameras installed in the rear of the body, the Side-rear Monitor System is designed to constantly watch rearview blind spots and inform the driver of the presence of any vehicles close to his own when making a lane-change maneuver, as well as prompting him to take care. In this way, the system is designed to help prevent accidents that are due to the driver paying insufficient attention to the road behind him.
The system comprises: Wide-angle lens CDD video cameras installed in the rear of the body; A turn indicator lever that recognizes when the driver intends to make a lane-change maneuver; Sensors that monitor vehicle's running status and; Audible and visual warning indicators. The system also serves as a rearview monitor for reversing maneuvers, when images from the CDD camera are displayed on a monitor.
Side-rear Monitor System
The system video cameras constantly monitor the adjacent lanes behind the vehicle that can so easily be blind spots. When a vehicle or motorbike coming from behind enters the camera's field of view, this covering most of the area not visible in the rearview mirror, it is recognized as an approaching vehicle. Regardless of whether there is any vehicle in the monitor field, the Side-rear Monitor provides audible and visual warnings to prompt the driver to check the road behind him whenever he operates his turn signal at the start of a lane-changing maneuver.
The system encourages safer driving by warning the driver, when he operates his turn indicator, of the presence in the rearview blind spot of an approaching vehicle in the adjacent lane,.
3. Preview Distance Control
In addition to its cruise control features, the system is designed to help prevent tail shunting accidents by automatically adjusting inter-vehicle distance with the vehicle ahead, and by warning the driver when it judges his vehicle is getting too close to the one ahead. Regulating inter-vehicle distance as it does, this highly-advanced adaptive cruise control is designed to further ease the load on the driver.
The system comprises: A laser radar that measures inter-vehicle distance with the preceding vehicle; Sensors that monitor vehicle status and the driver's operation of his vehicle; An audible and visual warning system that urges the driver to be careful and; A controller that regulates engine output and the automatic transmission.
Preview Distance Control System
Using the laser radar to measure the distance to the vehicle ahead, the system regulates engine output and the automatic transmission to keep inter-vehicle distance at a safe level. The system provides the driver with an early warning when it judges the vehicle is getting too close to the one ahead.
(*1) Intelligent Transport Systems: Known as Advanced Traffic Systems in Japan, these encompass a number of areas, including traffic control and public transport.
(*2) Advanced Safety Vehicle: Aims at improving active safety performance, chiefly by making vehicles "smarter".
(*3) Automated Highway System: A public demonstration of automated driving and other AHS features was given in October 1996 using road infrastructure on the Joetsu Expressway before it was officially opened.
(*4) Intelligent & innovative Electronic Control System: Introduced by MMC in May 1992; a world first. Uses advanced logic circuitry in the shift scheduling of the automatic transmission and in the TCL (Traction Control System) to realize significant advances in easy-drive qualities.
(*5) Introduced by MMC in January 1995; a world first. To the advanced TCL features that enhance tire grip on slippery surfaces, is added a Preview function, which automatically reduces engine output if the system senses the vehicle is about to enter a corner too fast when the navigation system's Route Guidance Mode is engaged.
(*6) Introduced in January 1995; a world first. Using a laser radar to monitor the distance to the vehicle ahead, this system regulates engine output to keep a safe inter-vehicle distance. The system also provides voice and visual warnings that urge the driver to slow his vehicle should the distance to the vehicle ahead start to close suddenly.
(*7) Active Yaw Control: Introduced in August 1996, a world first. The system generates a yaw moment by controlling torque split between left and right rear wheels on 4WD vehicles, thereby enabling the vehicle to follow the driver's chosen line.
(*8) Active Stability Control: Introduced in August 1996. The system regulates braking force independently at each of the four wheels, thus promoting a stable body attitude when braking on slippery surfaces.