To most people, the words “driving simulator” probably conjure up thoughts of video games. That’s understandable: franchises likeGran TurismoandForzahave sold in the tens of millions. While the fidelity of even those games islittle short of amazing, at the end of the day, they’re games first and foremost. But there are other good reasons to simulate driving, whether that’s tostudy distracted or impaired drivingor tobetter engineer a race car. As you might imagine, these simulators are a little bit more specialized than a games console and a steering wheel—and a good deal more expensive, too. What you may not imagine is that one of the most advanced driving simulators in the world, not to mention one of the largest and most expensive, can be found in Coralville, Iowa.
It’s called the National Advanced Driving Simulator (NADS). Actually, the facility—one of our national labs and managed by the University of Iowa—is called NADS; the really expensive driving sim is called NADS-1, and it’s a sight to see. In fact, until Toyota built a new simulator in Japan in 2007, it was the most advanced driving sim on the planet, and it still has the second-largest motion envelope of any driving simulator that currently exists. (There’s also a NADS-2, which isn’t quite as advanced because it doesn’t move.)
NADS-1 lives in a hanger-like chamber, smaller than a football field, bigger than a basketball court, and looks similar to the very high-end flight simulators you might find at Boeing or Airbus. There’s the dome—a white capsule large enough to fit a full-size car or even the top two-thirds of a class 8 truck—around which is displayed a 360-degree virtual environment. The dome is mounted atop six hydraulic legs, which let it pitch forward and back and roll from side to side. The legs are mounted upon a rotating ring, which lets the entire unit yaw from side to side, and the whole arrangement is fixed to an X-Y platform that lets it move within the room, to better simulate a vehicle accelerating and braking.
Even so, NADS-1 has some limitations. “The space that we have in the bay out there is not enough room to do 1:1 motion for a braking maneuver from high speed to a stop, so we still have to scale our motion,” explained Chris Schwarz, director of engineering and modeling research at NADS. “But we can play some tricks with emotion. Like if you’re braking, then we can translate you in the room, which is how you experienced braking in the car. But if we run out of space in the simulator, which we most likely will, then we can transition some of that deceleration cue into tilt and let gravity take over that cue. And while it’s doing that, then we can take the dome and slowly pull it back to the center of the room to prepare for what’s next, which is likely an acceleration from start to back up to speed,” Schwarz told me.
During our visit, the dome was set up with a full-size car mounted on four more actuators that are there to simulate the bumps and vibrations you’d expect when driving over different road surfaces. Above it, 16 LED projectors each throw a 1920×1200 slice of the simulated environment onto the walls of the dome. The virtual environment is called Springfield for the same reason Matt Groening chose it forThe Simpsons, and it’s a 285-square mile (738km2) digital proving ground that includes a mix of urban and suburban streets, rural highways, and divided-lane interstate highways. (It also contains some familiar-looking buildings if you know Iowa City and Coralville.)
So, you don’t use it to play games?
Similar to Ford’s VIRRTEX—the lastreallyexpensive driving simulator I visited—NADS-1 is used for a lot of human factors research, and currently it’s in the middle of a study on theoh-so topical problem of distracted driving and conditional automation.
“The main theme is to make sure of the driver’s readiness in level 3 automation. [This is when the car isfully responsible for driving and situational awareness, but the human driver must be ready to resume control when asked.] So we’re interested in assessing the driver’s cognitive and physical capabilities when you are giving them a takeover request, because in level 3 automation drivers can be, you know, out of the loop, doing many other things,” said Pujitha Gunaratne, a researcher at Toyota’s Collaborative Safety Research Center who is working with NADS.
Since the point is to study driver behavior, the interior of the Camry was dotted with a number of cameras to observe the driver from multiple angles, plus infrared LEDs to provide illumination and a decidedly non-standard heads-up display. Both this HUD and the digital display between the car’s analogue dials were configured to show feedback on which automation state the car was in. Rather than just explain to me what the research involved, Schwarz, Gunaratne, and their colleagues kindly let me have a go, running me through an abbreviated set of tests.
After getting comfortable and up to cruising speed on the highway, I was asked to engage the car’s level 3 automation, then busy myself answering a number of multiple-choice quizzes on a tablet. (The science questions were fiendishly difficult, and many involved recognizing 18th-century portraits to determine which long-dead white man gave his name to some physical property or other. I felt quite demoralized with how low my score was.) At various points, an event would occur requiring my attention on the road—a suddenly stopped vehicle in my path, for example, or a temporary lane closure—sometimes while I was driving, sometimes while I was distracting myself with the tablet. How slowly or quickly I responded, as well as all my control inputs into the car, were all cataloged by the array of cameras and sensors, which would have been added to the study’s dataset had I been a real research participant.
They have real cars, too
“We want to try to understand the space of what drivers are going to be doing in these higher levels of automation and what impact those different types of tasks have [regarding] engagement with the driving tasks. So this interplay between the cognitive demand of a task, how much it pulls your mind away from driving, and the physical demands, how much pulls your parts of your body away from dragging,” said John Gaspar, director of human factors research at NADS. The precise nature of distraction is an active area of investigation these days, with at least one recent study suggestingthat it’s all to do with where your eyes are, althoughmuch moreresearchshows how poorwehumans are at multitasking.
To that end, NADS has a number of instrumented test vehicles which can do some on-road confirmation of simulator findings. In this case, I visited a decommissioned stretch of nearby runway, about a third of a mile (500m) long. As with the driving sim, I got to play guinea pig behind the wheel of a white Tesla Model S, with instructions to follow a chase car with the car’s adaptive cruise control and lane keeping engaged. (The runway had been marked up with lane markers to be legible to the car’s lane-keeping camera sensors.) Each time, I was given a different task to perform while cruising behind the chase car—searching for NADS’ homepage on the Tesla’s infotainment screen, composing an email on my phone, and counting loose change from the cupholder. At some point, the chase car would brake or change lanes to reveal a lane closure, requiring me to react.
I knew there was going to be an event requiring my attention before too long, given the relatively short length of the runway, which means I didn’t devoteallmy attention to the distracting task at hand. And I knew that there was little danger, what with the lack of any oncoming traffic or highway infrastructure with which to collide at speed. Even then, I still ended up having to brake harder and with less margin between me and the car ahead than I’d be comfortable with in the real world. Given that the problem of distracted driving continues to get worse, it evidently does bear saying: don’t do any of those things if you’re also simultaneously in the driver’s seat of a moving automobile, even if you do have a full suite of advanced driver-assistance systems!
Listing image by Toyota