ARI SHAPIRO, HOST:
Now a mystery solved in Arlington, Va. It starts with an unmarked Ford passenger van making its way through suburban streets with an apparently empty driver's seat. Adam Tuss of NBC Washington was on the case.
(SOUNDBITE OF ARCHIVED RECORDING)
ADAM TUSS: Brother, who are you? What are you doing? I'm with the news, Dude. Can you pull over, and we can talk for a second?
AUDIE CORNISH, HOST:
Tuss uncovered that the empty car wasn't what it seemed. That got the attention of Wired reporter Aarian Marshall.
AARIAN MARSHALL: There's a person inside the car, but that person is dressed as a car seat.
CORNISH: Someone covered from head to waist in what looks like car seat upholstery.
SHAPIRO: The only clues that it's not a car seat are the hands sticking out from the costume, holding the steering wheel.
CORNISH: It turns out it's all in the name of science. The reporters learned it was part of a study by the Virginia Tech Transportation Institute about self-driving vehicles.
MARSHALL: So scientists want to figure out how people react to these vehicles when there's absolutely no one behind the wheel, when there's no one inside. So that's why they put out these strange car seat costume studies into the field.
SHAPIRO: The researcher who pioneered the concept, Wendy Ju at Stanford's Center for Design Research, says she got the idea from a prank video.
WENDY JU: There's this wonderful YouTube video that shows a person driving through drive-throughs in a car seat costume and just scaring the bejesus out of poor fast food workers.
(SOUNDBITE OF ARCHIVED RECORDING)
UNIDENTIFIED MAN: I built this car seat costume. I'm going to put it on, and I'm going to go through a drive-through.
UNIDENTIFIED WOMAN #1: Hello. Oh, my God, (unintelligible).
UNIDENTIFIED WOMAN #2: Hello. Are you serious?
UNIDENTIFIED WOMAN #3: Interesting. All right, empty car, can I have $1.43 please?
UNIDENTIFIED WOMAN #4: What the hell? I don't like this.
CORNISH: Those videos are from 2013, but the idea of driverless cars is still going to take some time to get used to.
(SOUNDBITE OF QUITAPENAS SONG, "YA VERAN") Transcript provided by NPR, Copyright NPR.