A precrash system is a automobile safety system designed to reduce the severity of an accident. Most are also known as forward collision warning systems which use radar and sometimes laser sensors to detect an imminent crash. Depending on the system they may warn the driver, precharge the brakes, Inflats seats for extra support, moves the passenger seat to a better position, folds up the rear head rest for whip lash, retract the seat belts removing excess slack and automatically apply partial or full braking to minimize the crash severity. In 2009 the NHTSA began studying whether to make frontal collision warning systems and lane departure warning systems mandatory.[1]