TRW Automotive Holdings Corp. recently unveiled an advanced pre-crash radar system that uses the latest-generation Adaptive Cruise Control (ACC) and Active Control Retractor (ACR) technologies. By combining these active and passive safety systems, TRW helps vehicles avoid accidents, and protect passengers in case an accident is unavoidable.

ACC uses radar sensors to slow down the car automatically when it is moving too close to the car ahead, then accelerates back to the last cruise speed once the car is a safe distance away. TRW improved upon this detection technology with its second-generation AC20 radar, which has an enhanced range of 200 meters. When the radar detects the gap between vehicles closing too quickly, it not only signals the ACC system but also activates the ACR system. The ACR tightens seat belts to better position passengers for a potential crash and warns the driver of the impending collision. If the crash is avoided, the system reverses itself and loosens the seat belts.

The pre-crash system uses a situation-management algorithm that continuously processes signals from the vehicle's relevant dynamic systems, such as ABS (anti-lock braking systems), electronic stability control, and the TRW ACC radar. It evaluates events like braking, sliding, vehicle angle and objects detection, and determines if a critical situation has been reached that warrants the activation of the ACR system.

These pre-crash systems open many other possibilities for integrating radar detection into future vehicles. For example, ACC technology could be used to implement self-braking systems that can sense a crash and hit the brakes preemptively. The system could also be used to warn the driver of impending danger or even jolt a drowsy drive awake with a vibrating steering wheel.

To read more about ACC click here.