Toyota drifts its driverless Supra: What kind of wizardry went into making this happen?

Toyota Supra self-drift

Autonomous cars, in the kind of future we imagine, may be a long way away, but that isn’t stopping manufacturers from looking at that kind of autonomy. While we imagine going from point A to point B without ever having to touch a steering wheel, let alone look at the road, the people at Toyota are making their cars go sideways.

The Toyota Research Institute has developed what it claims is the first autonomous drift car — a Supra that is able to slide around a track like it comes straight out of the Fast and Furious movies. And while the car itself is specced more for a race than a conventional day on the road, it still shows what the system can do.

A souped up Supra

Toyota tested their Supra on Thunderhill Raceway in California, United States. The car had to be modified to a large extent. The technology used is called Nonlinear Model Predictive Control (NMPC). While most autonomous systems use closed loops and tracks to steer the car, the NMPC controller takes that control and pushes it sideways. What this essentially results in is a controlled slide sideways to avoid obstacles and collisions. In other words: A drift. According to Toyota, that system makes calculations about 20 times a second.

This new self-drifting system was developed in collaboration with the Dynamic Design Lab at Stanford University. Drift Legend Ken Gushi was also on the team and was the driver behind the wheel of the test car — all he had to do was hit the engage button.

The NMPC controller is all that the car was modified with. The steering, throttle and clutch are all computer controlled (duh!). The transmission, too, is a sequential gearbox and each wheel could be individually braked. These are modifications that you see on normal self-driving cars as well. But to allow for a drift, the Supra also had to be tuned towards performing on a race track rather than a street. Everything from the engine, transmission, suspension and chassis were tuned to similar specifications as you would find in a Formula Drift competition.

What will it be used for?

While the idea behind a car that can drift on its own is an exciting one, don’t expect it to hit the streets anytime soon, or even ever, for that matter. The point of a car that can drift leans more towards safety than anything else. While cars today may detect accidents and hit the brakes or even swerve slightly in either direction, a car that can control itself while moving completely outside the bounds of traction could potentially save more lives.

For example, imagine a situation in a snowy winter region when the car hits black ice. If you’re lucky, you sail past it without being any wiser. On the other hand, what usually happens is you will start sliding. A traditional stability control system would try to intervene and try to straighten the car out. A straight line and a properly controlled slide could mean the difference between staying on the street and ploughing into the side of the road.

“When faced with wet or slippery roads, professional drivers may choose to ‘drift’ the car through a turn, but most of us are not professional drivers. That’s why TRI is programming vehicles that can identify obstacles and autonomously drift around obstacles on a closed track,” says Jonathan Goh, TRI research scientist.

The real-world application of this kind of technology is vast. Researchers and developers may be the only people allowed to play around with self-drifting cars, but when the technology does make it to the market, if you’re lucky (or unlucky), you’ll get to see your car in action.

“Through this project, we are expanding the region in which a car is controllable, with the goal of giving regular drivers the instinctual reflexes of a professional race-car driver, to be able to handle the most challenging emergencies and keep people safer on the road,” says Avinash Balachandran, senior manager of TRI’s Human Centric Driving Research department.

Toyota Guardian

Toyota is also working on a safety system that would appeal to enthusiasts rather than conventional everyday drivers. Known as The Guardian, this system allows most of what a driver would do with the car, but takes control in an unexpected situation.

In a press statement, Toyota said: “With Toyota Guardian, the driver is meant to be in control of the car at all times except (when) Toyota Guardian anticipates or identifies a pending incident and employs a corrective response in coordination with driver input.”

The fact that manufacturers are now starting to electrify their range of cars also means that safety systems can run off the same computers that already control the car’s electric motors. Sure, conventional ICE engines are not much different these days either, but the latency in input is different. Then, there is the need for a separate battery to power the electronics in the car whereas an electric car runs on just one big battery pack.

For what it’s worth, we cannot wait to see this tech on the streets. Accidents rarely occur because a driver failed to spot a truck a mile away and forgot to brake. In most instances, it’s another vehicle or object popping up out of nowhere that does the damage.