Mystery solved: What are those little robot cars driving around the Olympic track and field stadium?

If you tune in for an Olympic track race, you may or may not notice a small group of cars milling about in the infield.

There aren't large cars, barely taller than the knees of the Olympic staffers and volunteers walking among them. They're mostly black and white, and it's immediately unclear what purpose they serve if you're just seeing them in the foreground or background of a race like this one:

Here's a closer look at one:

Jul 30, 2021; Tokyo, Japan; A remote control discus transporter in the infield during the Tokyo 2020 Olympic Summer Games at Olympic Stadium. Mandatory Credit: James Lang-USA TODAY Sports
A closer look at the track-and-field cars at the Olympics. (James Lang-USA TODAY Sports)

So, what are these futuristic-looking interlopers? Well, the reason they may be a mystery for people watching the "track" part of track and field is that they haven't seen them in action during some other events.

What those little Olympic track-and-field robots do

The little cars are, in fact, recovery robots used to transport thrown objects (e.g. discus, javelins, hammers) back to where they belong after athletes make use of them. Such cars have actually been used at past Olympics, with different aesthetics.

At Rio, they were tiny pick-up trucks.

A remote control car carries discus in the Men's Discus Throw Qualifying Round during the athletics event at the Rio 2016 Olympic Games at the Olympic Stadium in Rio de Janeiro on August 12, 2016. (Photo by FRANCK FIFE / AFP) (Photo by FRANCK FIFE/AFP via Getty Images)
Olympic robot car circa 2016. (Photo by FRANCK FIFE/AFP via Getty Images)

And in London, mini-Mini Coopers (of course).

LONDON, ENGLAND - AUGUST 08:  A remote control Mini car is used to return the hammer in the Women's Hammer Throw Qualifications on Day 12 of the London 2012 Olympic Games at Olympic Stadium on August 8, 2012 in London, England.  (Photo by Michael Steele/Getty Images)
Olympic robot car circa 2012. (Photo by Michael Steele/Getty Images)

The real twist with Tokyo's recovery robots is that they have switched from remote control cars like the two above to cars operated by artificial intelligence.

Per the Olympics' release announcing the robots' existence, the cars are made through a partnership with Toyota and use their onboard cameras and computers to determine the optimal path to transport their cargo.

They do still need a hand actually picking up the stuff, though:

The cars — er, field support robots — are part of a fleet of robots deployed by the Olympics and Toyota in Tokyo, including some rugby ball-transporting siblings. Of course, none can hold a candle to our new basketball-shooting overlords.

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