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Collision Warning

Fig 1: Identifying Collision Warning System
GLL170520Courtesy of VOLVO CARS CORPORATION

The collision warning function is designed to warn in case of high likelihood of collision with a vehicle ahead, moving in the same direction and which suddenly brakes.

The collision warning system makes calculations when a warning is to be activated. The calculation is based on the speed of the approaching vehicle and of the vehicle itself. Normal reaction time, that approximately 85% of all drivers have, is compensated for in the calculation, the system's response time is also compensated for. If the warning distance is greater than the measured distance to the approaching vehicle and the driver has not taken any action, a warning will be activated. The warning consists of a combination of light and sound. The combination is set by the user/driver.

The visual warning is generated by means of the indicator, visual collision warning (27/2) and the audible warning is generated by means of the Driver information module (DIM) (5/1). The Forward Sensing Module (FSM) (4/80) transmits a request via CAN to the Driver information module (DIM), which generates the audible warning. The Forward Sensing Module (FSM) also transmits a request to the Infotainment control module (ICM) (3/281) to lower the sound (stereo) to the speakers during the period that the audible warning is generated by the Driver information module (DIM).

The collision warning function shall activate a warning so that approx. 85% of all drivers have a chance of stopping or reducing a collision with a vehicle ahead in a situation where a collision is imminent, on the condition that you maintain a time distance of more than 2 seconds to the vehicle ahead.