The hype over self-driving cars has hit a fever pitch. Google is working on one. So are Audi and GM. Ford says it will wait until the technology really works and rumors surround an Apple driverless vehicle, whether or not the company is actually working on one.
Along with the drumbeat of inevitability have been warnings of what could go wrong. Self-drivers could potentially be the first deadly robots. State regulators wonder how to handle the phenomenon. Car hacking could be a big threat.
But the critics have largely ignored one major issue: motion sickness. A new study from the University of Michigan’s Transportation Research Institute examined what consumers have said they wanted to when cars could pilot themselves and correlated those activities with a likelihood of generating motion sickness.
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Many people want to read, text or talk with family and friends, watch videos, work, or play games. The problem is that such activities require eyes to be open and focused on something other than the road, unlike either following the progress of the vehicle or closing eyes to rest or take a nap. The activities set the groundwork for a conflict between visual senses and the body’s vestibular system, which senses movement and helps establish a person’s sense of balance.
According to the group’s estimates, given consumer activity preferences, between 6% and 10% of American adults riding in a self-driving vehicle would “often, usually, or always experience some level of motion sickness.” Between 6% and 12% would experience “moderate or severe motion sickness at some time.”
“Not enough attention has been paid to this important issue,” Michael Sivak, director of Sustainable Worldwide Transportation at TRI and a co-author of the study, wrote in an email to Fortune. “It is an issue that needs to be dealt with, especially since being able to do many of the activities that increase motion sickness is touted as one of the benefits of self-driving vehicles.”
Have manufacturers considered the issue? “I hope so,” he wrote.
Manufacturers could minimize the problem with electronic displays that they required someone to look straight ahead, outfit cars with large windows, or design seats to restrict head motion or to allow someone to lie flat. For the companies that don’t, susceptible consumers who must ride in a self-driving car could take appropriate medicine before a trip, ride with their eyes closed, or take a nap and wait for the ordeal to be over.