Driver simulation is a remarkably powerful research tool. It allows us to safely and affordably explore how people handle potentially deadly situations. We can create scenarios (e.g., poor visibility, impaired driving, malfunctioning ADAS systems) that would be logistically impossible (as well as unethical) to ask study participants to endure in real life.
So it’s tremendously frustrating that the primary limiting factor to many simulation studies is human frailty in the form of simulator sickness. One recent study dryly noted that when doing research that hinges on driver simulation, “Supplies such as sick bags, plastic gloves, mouthwash, and cleaning products should be kept in the lab.”
But this isn’t just a matter of participant (and lab tech) discomfort. Johnell Brooks and her research team point out that “This malady, similar to motion sickness (MS), can potentially confound data, limit the effectiveness of training, and influence participant dropout rates.”
The Challenge of “Long Drive” Studies
In general, researchers find that participants will tend to show symptoms of simulator sickness after 10 minutes in the simulator. But these symptoms tend to become more severe (and thus increasingly disruptive) as the length of the exposure increases. Studies that rely on long simulated drives are inherently more challenging—and more likely to lose participants or suffer tainted findings.
This makes some topics disproportionately more difficult to research. For example, rural commuters tend to have long commutes covering many miles at high speeds, with many unsignalized intersections. They encounter a wide range of vehicles—not just other cars, but also motorcycles, bicycles, commercial hauling vehicles, and slow-moving agricultural equipment. In order to improve the safety of rural drivers, a simulation needs to account for all of this. That translates to long simulated drives, which are just the sorts of studies most stymied by simulator sickness.
Choosing Your Driver Simulation System
For example, Nichole Morris’ 2019 rural traffic safety study needed to emulate a wide range of interactions at rural “thru-stops” (i.e., intersections where the slower “minor road” has a stop sign, while the faster-moving “main line” does not). They ultimately designed a 19-mile drive down a simulated rural main line road, with 18 separate thru-stops. For the average person, that’s a very long time to endure in a driving simulator, well past the point where many begin to become very motion sick. The University of Minnesota had a history of participants getting sick during studies like these. When it came time to renovate their HumanFIRST (Human Factors Interdisciplinary Research in Safety and Transportation) Laboratory, finding a new simulator that would minimize simulator sickness was a priority. They determined that RTI driver simulation systems were especially well-suited to such long drive studies:
“One of the key competitive differentiating features of the [RTI] simulator, was the partial motion system, which helps to stimulate a driver’s vestibular system and, importantly, reduce the risk of simulation sickness, which is a common result of experiencing visual motion without vestibular motion. This also provided a realistic and immersive feel to the simulation, thus enhancing the validity of the experimental results.”
We’re pleased to have helped U-M find the right driver simulation platform for their study—and look forward to talking to researchers about what they plan next.