Nissan has made another stride toward that strange but often-promised future: cars that drive themselves. A new system set for release in Japan links information from a car’s real-time GPS navigation with existing radar-guided safety tech to help drivers make smooth turns on curvy roads. The Navigation-Cooperative Intelligent Pedal uses GPS mapping data to detect an oncoming bend, then strategically decelerates or applies the brakes. Here’s how it works: When the nav system indicates a curve is looming, the accelerator pedal physically moves upward. Then the system activates the brakes. The point is to reduce a driver’s workload on winding roads, such as Japan’s notoriously curvy mountain highways.

The Navigation-Cooperative Intelligent Pedal works along with Nissan’s new Active Stability Assist system, which synchronizes braking, steering and engine responses. The system monitors a driver’s steering and acceleration/braking patterns, and steps in with either braking or the application of engine torque to each of the four wheels to help smooth vehicle responses. During braking, the system judges the distribution of force to each of the four wheels depending on the radius of a curve. The point, Nissan says is to help a driver feel more in control.

Nissan says both systems will be introduced on the new Fuga, a car US buyers know as the Infiniti M, in Japan in fall 2009. No word on a US release. Sounds like it may come in handy more in Japan than in the US, unless your morning commute is climbing Pike’s Peak. Wake me up when it can cross-reference the caffeine level in your bloodstream, and apply the brakes in front of the nearest Starbucks.

[via Nissan]