The system is designed primarily to help the driver (and car) avoid collisions in circumstances where braking alone won’t be sufficient. According to Nissan, such situations could include “sudden intrusions onto the road in low speed zones, or when a collision at high speed is imminent due to the driver's delayed recognition of the tail end of a traffic jam.”
Cars using the system would be equipped with front-mounted radar and a video camera, two left and right rear radars, and five laser scanners mounted around the vehicle – this combination would give it a 360-degree view of its surroundings. Using output from these, the system’s Electronic Control Unit (ECU) would identify situations in which a collision was imminent.
If that collision could be avoided by braking, the ECU would first warn the driver of the impending danger, and then proceed to apply the brakes if the driver failed to do so themselves.