In the same way that we didn’t go straight from landline phones to smartphones, there are likewise going to be some intermediate steps between today’s manually-driven cars and tomorrow’s fully self-driving models. We’re already seeing some of those steps starting to pop up, in the form of things like Cadillac’s Super Cruise control, Volkswagen’s Temporary Auto Pilot, and Volvo’s traffic jam assistance system. Nissan’s latest contribution is its recently-announced Autonomous Emergency Steering System.
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.
In some situations, however, the ECU might decide that braking alone wouldn't be enough. In those cases, it would proceed to check for vehicles approaching from the rear, and for forward zones that were free of obstacles such as other vehicles or pedestrians. It would subsequently alert the driver with a series of audible beeps, and a visual display that indicated the direction in which the vehicle should be steered. If the driver didn’t react immediately by steering in that direction, the system would take over and do the steering itself.
It’s actually very similar in principle to the semiautonomous collision avoidance system being developed at MIT. That system also temporarily takes control of the steering when a collision is imminent, to guide the car into a “safe zone.”
Nissan’s Autonomous Emergency Steering System is one component of the automaker’s Safety Shield program, and is still in development. Another system created under that program, however, should be available in the Nissan Elgrand as of early next year – it uses video signal data to assess the car’s surroundings, and will suppress acceleration if the driver accidentally guns the gas pedal in a confined area such as a parking lot.