Fuji Heavy Industries Ltd unveiled a next-generation Active Driving Assist (ADA) system using stereo camera. The system, now under development, is scheduled to be employed in new Legacy slated for launch in 2008.
The system uses a newly developed stereo camera and image processing circuit to detect pedestrians, bicycles, vehicles, etc. When the system detects an immediate danger, it activates the pre-crash safety system to automatically apply the brakes.
Similar systems thus far launched from other manufacturers use a radar device or a combination of radar and camera. Thus, this is the first time in the industry to implement pre-crash safety with a camera alone. The system detects the contour of the obstacle and determines whether it is a pedestrian based on the pattern recognition technology.
The automatic brake activation timing of the pre-crash safety system is compliant with the new technical guidelines. When the system determines that a collision cannot be avoided, it activates the brakes and applies a force of 0.51 G or higher 1.4 seconds prior to the crash, whereas the existing guidelines specify that brakes should be applied 0.6 seconds prior to the crash.
"It is technically possible to avoid collisions with automatic brakes alone," an engineer in charge of development said. "But we are considering allowing slight bumping in the actual implementation," the engineer added. "We are afraid that drivers would depend too much on the system if it completely prevented collisions."
The system also provides pre-crash safety in the low-speed range for the first time in the industry. The safety systems developed by other auto manufacturers like Toyota Motor Corp, Nissan Motor Co Ltd and Honda Motor Co Ltd are activated in the high-speed range of at least 15km/h.
"According to the technical guideline, the provision of safety measures in the speed range lower than 15km/h is at the discretion of each auto manufacturer," said the engineer. "But we decided to employ the system because we discovered that damages of accidents can be reduced more effectively by providing it in the low-speed range when considering the driving conditions in urban areas."
Furthermore, Fuji Heavy Industries' next-generation ADA is capable of reducing the damage caused by erroneous start due to the wrong shift lever operation by the driver, again for the first time in the industry. When the stereo camera detects a wall or an obstacle in front of the vehicle, the system eases back on the throttle even if the driver accidentally shifts into Drive and steps on the accelerator.
From the standpoint of maneuverability, the company disagrees with the idea of completely stopping the engine when an obstacle is in front of the vehicle.
"If the system completely negates the operation of the accelerator when an obstacle is ahead, the driver will be unable to reduce the distance to the preceding vehicle or to steer when the car is close to the obstacle in front," said the engineer.
In addition, if the driver continues to press the brake pedal, the Pre-crash Safety System will automatically activate the brake before the crash to reduce the damage of collision.