When That Child in the Street Is an Optical Illusion

Let’s say you live or work in an area where there are a lot of vulnerable pedestrians – kids, maybe – and a lot of cars as well, and that the cars habitually drive too fast for your taste.

What do you do?

Maybe you put up some warning signs, or speed bumps, or try to get the police to strictly enforce the speed limit.

Or you could try this:

According to the Star, this is a “heat-plastered decal” installed on a street near an elementary school in West Vancouver. For oncoming drivers, it creates an optical illusion that there’s a little girl chasing a big pink ball in the middle of the street:

The decal on the road appears to drivers as they approach the image from 100 feet away, the sweet spot is between 10 and 50 feet away when the girl appears in 3D for a brief second. … The $15,000 decal was paid for by Preventable.ca, a non-profit organization that works with the BCAA Traffic Safety Foundation, WorkSafeBC and other groups aimed at preventing accidents.

The goal is obviously noble: to cut down on traffic injuries and fatalities of children. But, as with the fake speed bumps in Philadelphia, one can imagine a host of unintended consequences:

  • After you’ve seen the illusion once, does it lose – or negate – its effectiveness? Do you assume that a real kid in the street is just another decal?
  • A driver who sees the decal for the first time and slams on his/her brakes may increase the chances of a rear-end collision — kind of like the red-light-camera effect.
  • What happens if a driver responds to the illusion by driving off the road and hits a real person, or has a heart attack?

It should be noted that the decal was removed after one week. It was an experiment, a stunt, designed to create awareness around the school. It easily did that, and beyond.

(HT: Brad Garland)

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  1. brazzy says:

    None of the “unintended consequences” sound realistic to me after watching the video – drivers see that there’s something on the road all the time, it just gradually turns into a lifelike image as they approach the right spot.

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  2. Ian Kemmish says:

    If you want to surprise the driver into remembering that there’s a school about and it’s the start of term, then the low-tech approach may be better:


    Nobody is going to forget a horse painted as a zebra in a hurry.

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  3. Brett says:


    That’s assuming that drivers are as singly-focused as viewers of the video. In reality people will be distracted, looking elsewhere, talking to another person in the car, etc. It certainly wouldn’t happen to every single driver, but in my opinion it’s not at all far fetched to imagine that a distracted driver first glancing at the decal while it’s in the sweet spot could panic and cause real harm to themselves or others.

    And let’s not pretend that we can avoid distracted drivers, no one can focus on the road 100% of the time, our brains just don’t work that way (and because obstacles don’t only approach from directly in front of us, that type of tunnel vision would be dangerous).

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  4. Matthew Huggins says:

    Throw away your civil engineering codes, narrow the streets and line them with on street parking.

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  5. Eric M. Jones says:

    I’d worry that these might teach you to ignore stuff in the road.

    In the Yucatan they use speed bumps “Topos” with a warning sign that looks like two breasts. Apparently you can install your own local topos if you think it is needed with or without warning sign.. You can spot the topos and slow down 99.7% of the time. There are tens of thousands of them.

    The 3/1000 that you fail to see and react to will really teach you religion.

    Ask me how I know….!

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  6. Trish says:

    I think it would distract me from actual happenings around me (perhaps a kid or dog or car), and I am enough of a geek to go around the block to see it again, and focus even more on it – what does it look like from the other direction… I akshully :-) think it might just be an accident waiting to happen.

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  7. jimi says:

    Yay! Compliance through deception.

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  8. Chet says:

    How about the unintended consequence of increasing the amount of traffic in the area due to the unique nature of the forced-perspective artwork? Can’t you imagine the traffic would increase in the area as word of it got around – much like a unique lighting display would attract more cars to a neighborhood during the holidays.

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