A team from Stanford’s Dynamic Design Lab led by Jonathon Goh including Chris Gerdes was formed to convert a 1981 DeLorean DMC-12 into a self driving, all electric, drifting machine with robotic precision. In a nod to Marty McFly from Back to the Future, the car was named “MARTY” which stands for “Multiple Actuator Research Test Bed for Yaw Control”. The true purpose was to test new systems, control and accident prevention algorithms for future autonomous vehicles. Current stability control systems keep a car within the stable handling limits imposed by friction, these new systems are for cases when a driving system needs to understand and exceed these limits to avoid a collision.
With assistance from Renovo Motors, the car was fitted with a pair of 200 kilowatt motors (one on each wheel for precision control) and associated drive train. Replacing the original 153 lb/ft gasoline engine with the electric drive train with a claimed 4,000 lb/ft of torque. The motors are running at approximately 1/3 of their capacity in the video. After the electric conversion, the suspension and brakes upgraded, on-board control computers and GPS were installed.
Why a DeLorean? According to Jon, Stanford has history of working with major automakers and in this case didn’t want to risk conflict by choosing one over another. It was relatively inexpensive, simple to work on, and had the mid-engine, rear wheel drive layout the team was after.
The two passengers in the car never take control of the car at any point in the run. The car goes through hundreds of thousands of calculations per second in order to hold a calibrated drift angle of +/- 40 degrees, while also dealing with wheel friction and yaw rates as high as 120 degrees per second, knowing exactly when to turn, apply throttle, brakes and transition within an inch. The onboard computers can calculate a drift route in seconds when given a course layout. “The results so far are rather outstanding” said lead project engineer Chris Gerdes. “With MARTY we have been able to broadly define the range of conditions in which we can safely operate, and we have the ability to stabilize the car in these unstable conditions.”