Sensing that a crash is about to occur gives a car's safety systems vital microseconds in which to prepare. Pre-crash seatbelt tightening, for example, can save lives. But the radar, lidar (light detection and ranging) and computer-vision systems that look for tell-tale signs that a crash is imminent are not perfect, and false alarms must be avoided at all costs.
So US car maker Ford has come up with a probe about 10 centimetres long, which normally sits flush with the front bumper. This springs out if the vehicle's sensing system predicts that an impact is about to occur. The probe is therefore the first part of the car to make contact in a crash.
This contains sensors that determine how the probe deforms, and this in turn gives an indication of the mass and rigidity of the other object involved, whether a car, wall or person. The result is an accurate assessment of the severity of a crash in the instant before it occurs, giving the safety systems vital microseconds in which to prepare.
Read the full pre-crash probe patent application