Using sound to reduce motion-sickness in cars

Volvo thinks self-driving cars will create a motion-sickness problem: Because passengers will probably kill time by staring at their phones, they'll get queasy.

Seems likely! Motion-sickness is caused by a perceptual rupture — your body feels itself moving around, but your eyes see a stationary screen.

Volvo's engineers hypothesized that they could reconnect one's body to the movement of the car by using sound. So they created an experimental car that plays tones one second before accelerating, decelerating, or turning.

In one (quite small) study, the sounds indeed seemed to help reduce people's discomfort, as Popular Science writes:

The most compelling experiment took place on a closed airstrip in Sweden, near Gothenburg, in August of last year. (For other research, focused on the issue of trust, Volvo used virtual reality.) On that track, brave participants had to ride in the backseat of a car driven by a human and read from a tablet while the car navigated the course. The words they were reading came from what Hagman describes as "a very heavy text."

These riders "took three laps on this track," Hagman says. "After each lap, they were asked to rate their perceived motion sickness." Half of these guinea pigs had sound cues to help them during the ride, and half did not. Participants came back one week later to receive the opposite experience. The sounds reflected what the car was going to do in about one second: accelerate, decelerate, or turn. Volvo refers to these as "intention" sounds. (There's more info, and audio samples, here.)

With just 20 people, the study was small, but according to Volvo, the presence of sound cues made people report that they felt less ill. "As you took more and more laps, the effect even got more significant," Hagman says. "You could see that there was an effect of reduced perceived motion sickness when we added sound." [snip]

Volvo reports that participants said the sounds helped prep them physically, or "adjust their bodies," for what was about to happen.

It's a cool concept. And frankly I'd like to see this technology rolled out now, in cabs or ride-hail cars. I don't need to wait for self-driving cars to know that carsickness is an issue! When I take taxis in NYC, I frequently get wickedly carsick from all the sudden stops, starts, and rapid turns.

(CC-2.0-licensed photo of a car courtesy the Flickr feed of Brian Kelly)