Whether to Have Weather

One beautiful, sunny afternoon, as we stretched lazily out by the pool, we couldn’t help thinking about weather. We’re so lucky to live in Southern California where the weather is by and large fantastic. In fact, the weather here is so good that there’s a running joke about SoCal drivers not knowing how to drive in the rain (spoiler alert: it’s true).

Naturally, we started to think about weather and driving simulators. Does it make sense that a simulator should support “weather”?

Of course, almost everywhere else in the country, and the world, has lots of different kinds of weather to contend with. It makes plenty of sense that we should include weather effects in our driving simulations. Rain, snow, hail, and fog are natural occurrences that can happen while driving.

Yet, how does one create rain in a driving simulator?

Should We Simulate Weather?

Let’s back up for just a moment before we get too deep into the details of the weather. One of the primary goals with most simulators is for the user to receive a “positive transfer” of training. This means that the user will take what he or she learned from the simulation and apply it in a positive way in the real world.

In order to do that, the simulator must be able to simulate the real-world conditions as closely as possible, which will, in turn, increase the chance for a positive transfer of training.

And here is where the issue lies with adding weather events to a simulator: in real-world driving situations, if weather conditions become bad, the vehicle can become unstable. In the real world you would feel that instability as a physical sensation through your vestibular (balance system) and haptic (the seat pressing against you) systems, slightly before you visually see the problem. Without that physical feedback, the chance for a positive transfer decreases.

Thus, if weather effects are going to be included in a drive, some type of a motion system should also be in place so that the driver will receive the physical cues from their vestibular and haptic systems.

Believe it or not, there are motion systems available that will work with our (and other) driving simulators. However, to simulate an unstable vehicle correctly requires a sophisticated (a.k.a. expensive) system. That, in turn, requires a larger facility, regular maintenance, and a whole bunch of other factors (OSHA, anybody?).

We at STISIM Drive have come up with another way – depending, of course, on what you’re really trying to measure. If the weather effects are being used as a distractor (or another specific task), and the vehicle becoming unstable is not a factor, then we recommend using fog to add a layer of complexity.

Sure, fog doesn’t provide the distraction of the windshield wipers, or the visual effect of falling rain or snow, but it does change the visual field by decreasing the depth of the roadway and decreasing contrast sensitivity. Check out the three scenes below to see what we mean.

So, like we always say, think about what you’re really trying to measure before you decide you must have rain or snow. Maybe a little bit of fog would do the trick instead!