Control Module

Courtesy of VOLVO CARS CORPORATION

The Closing velocity module (CVM) is LIDAR-based (Light Detection and Ranging) and uses lasers to detect whether the vehicle is on a collision course with a vehicle ahead.

There is a sensor in the Closing velocity module (CVM) that transmits infrared laser light. The sensor transmits the laser light from three lobes (left, right and center).

If there is a vehicle ahead, the light is reflected and registered by the three photo diodes,

The control module measures the time it takes for the light to go from the sensor, reflect from the vehicle ahead, and back to the photo diodes. The time is used together with the vehicle speed to calculate the distance to the vehicle ahead and also the speed difference between the vehicle and the vehicle ahead.

The sensor is active within approx. 6 meters ahead of the vehicle.

The sensor senses vehicles that are stationary or that are travelling in the same direction as the host vehicle. The sensor also senses oncoming traffic, but the support function City Safety   does not react to oncoming traffic.

The Closing velocity module (CVM) has inputs and outputs for: 

• power supply
• ground
• CAN
• local in the CAN (only XC60 (MY -2012))
• sensor-CAN (only S60 (11-), V60, XC60 (MY 2013-), V40 (13-), V40 Cross Country).

External influences on the Closing velocity module (CVM) 

In some weather conditions, for example heavy rain, snowfall or fog, the performance of the sensor can become affected. This can mean that the sensor has difficulties in detecting vehicles ahead.

The performance of the sensor does not differentiate between day or night.

In order for the sensor to work optimally, the area on the windscreen in front of the sensor must be free of dirt, rain, ice and snow.

The sensor is positioned within the area of the windscreen wipers.