Bamboozled by stickers on street signs

Amid the rush to develop self-driving cars, there are a few questions that need answering. We’ve been worrying about hackers taking control of our autonomous vehicles, but it turns out they could be spooked by much simpler means. A team of researchers says strategically placed stickers on street signs could be enough to confuse self-driving cars.

The team, which included researchers from the University of Washington, University of Michigan, Stony Brook University and UC Berkeley, needed only a regular printer and a camera to trick the vision systems in their autonomous test subjects.

One method for bamboozling the self-driving cars involved printing a poster and simply sticking it over the existing sign. The result would look slightly off or faded to human eyes, but it caused the cars to misidentify the stop sign as a speed sign from a number of different angles. In the real world, that could obviously have some serious implications.

The other approach taken by researchers was more akin to an abstract art or guerrilla marketing project. The team stuck a few small stickers in strategic places on the stop sign and found they had the same impact as the full-sign coverup. Stickers reading “love” and “hate” made the cars think the stop signs were actually speed signs (or a yield sign, in one case), while smaller stickers placed around the sign had the same effect.

Gray stickers masking a right turn arrow made the test cars think it was a stop sign two-thirds of the time, or an added-lane sign for the rest of the time.