TTAC Reader Pits Simulated MX-5 Against the Real Deal [with Video]

by Ur-Turn

My company, Force Dynamics, builds full-motion driving simulators. They work by tilting you as the simulated vehicle corners or accelerates, so your brain is tricked into feeling lateral or longitudinal accelerations.

Sometimes people who watch our machines in action say, “This is moving way too much!” So when we started racing a Mazda Miata in the ChumpCar World Series, I decided to conduct an experiment.

We wrote an accelerometer application for Android (the existing ones weren’t useful due to their lack of adjustable damping) and mounted it in the car during my stint. Later, I put the same device on our motion platform, and recorded the same section of Watkins Glen in iRacing.

The result: a comparison of the forces you feel while driving a race car with the forces you feel while driving our motion systems. The phone, like your inner ear, can’t tell the difference between being accelerated or tilted. What you see on the phone in each half of the video is what I was feeling in the real car and in the simulator.

How do the two experiences compare? Practicality limits the simulator’s sustained force to about .6 g. Luckily, your perception is enhanced a bit: in the simulator, the force keeping you in the seat gets lower as you tilt, whereas in real life that force is always 1 g, so you feel more “oomph” for a given load in the simulator than you do in real life. There’s also a psychological component. You’re seeing yourself cornering, and you’re getting other secondary cues, too: in the 401cr, your rate of rotation; vibration; sound and fury.

How do the two differ? Well, the real car is easier: your positional awareness is better, and the onset cues are sharper, so it’s easier to read the car on turn-in. Those differences aside, however, I was almost immediately comfortable making the transition to real driving. Shifting, braking, cornering, and handling the car on the limit all made nearly direct transitions to the track; for example, I was immediately comfortable holding the car at small slip angles through long, fast corners, because it behaved exactly like I expected it to.

What this means is while the simulator can’t fully match the sustained accelerations of a real car, the overall feel can be very good, and a high-quality motion platform can help immensely in the transition from simulator to track.

If you have any questions, feel free to ask in the comments.

Submitted by David Wiernicki. You may know him as B&B member PeriSoft in the comments.


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  • Signal11 Signal11 on Jul 21, 2015

    Two words: that is super cool.

  • PeriSoft PeriSoft on Jul 21, 2015

    Hey guys - I'm the guy from the article there (and the Chump in the car). If anyone has any questions, fire away! As for the ones already asked... yeah, it's more expensive than a Chump Car, though I have to say it's probably not THAT much more than all the costs of a few guys running Chump for a couple of years. As for pricing, think about a 5-series. Not the one with pleather and manual mirrors; the one you'd actually drive. So yeah, it's not super cheap. But like I said, if you take running costs into consideration, it starts to look reasonable again, especially if you're comparing it to something like running SCCA regionals: Good luck pulling that off (in most any class) for under fifty grand a year. And then there's the thing I tell people on YouTube: You can crash a simulator more than once!

    • See 5 previous
    • Ryoku75 Ryoku75 on Jul 21, 2015

      @Ryoku75 I'm surprised you guys don't lease pre-built units. Not complaining though, I prefer the old "buy here, pay here, enjoy" formula.

  • Dartdude Having the queen of nothing as the head of Dodge is a recipe for disaster. She hasn't done anything with Chrysler for 4 years, May as well fold up Chrysler and Dodge.
  • Pau65792686 I think there is a need for more sedans. Some people would rather drive a car over SUV’s or CUV’s. If Honda and Toyota can do it why not American brands. We need more affordable sedans.
  • Tassos Obsolete relic is NOT a used car.It might have attracted some buyers in ITS DAY, 1985, 40 years ago, but NOT today, unless you are a damned fool.
  • Stan Reither Jr. Part throttle efficiency was mentioned earlier in a postThis type of reciprocating engine opens the door to achieve(slightly) variable stroke which would provide variable mechanical compression ratio adjustments for high vacuum (light load) or boost(power) conditions IMO
  • Joe65688619 Keep in mind some of these suppliers are not just supplying parts, but assembled components (easy example is transmissions). But there are far more, and the more they are electronically connected and integrated with rest of the platform the more complex to design, engineer, and manufacture. Most contract manufacturers don't make a lot of money in the design and engineering space because their customers to that. Commodity components can be sourced anywhere, but there are only a handful of contract manufacturers (usually diversified companies that build all kinds of stuff for other brands) can engineer and build the more complex components, especially with electronics. Every single new car I've purchased in the last few years has had some sort of electronic component issue: Infinti (battery drain caused by software bug and poorly grounded wires), Acura (radio hiss, pops, burps, dash and infotainment screens occasionally throw errors and the ignition must be killed to reboot them, voice nav, whether using the car's system or CarPlay can't seem to make up its mind as to which speakers to use and how loud, even using the same app on the same trip - I almost jumped in my seat once), GMC drivetrain EMF causing a whine in the speakers that even when "off" that phased with engine RPM), Nissan (didn't have issues until 120K miles, but occassionally blew fuses for interior components - likely not a manufacturing defect other than a short developed somewhere, but on a high-mileage car that was mechanically sound was too expensive to fix (a lot of trial and error and tracing connections = labor costs). What I suspect will happen is that only the largest commodity suppliers that can really leverage their supply chain will remain, and for the more complex components (think bumper assemblies or the electronics for them supporting all kinds of sensors) will likley consolidate to a handful of manufacturers who may eventually specialize in what they produce. This is part of the reason why seemingly minor crashes cost so much - an auto brand does nst have the parts on hand to replace an integrated sensor , nor the expertice as they never built them, but bought them). And their suppliers, in attempt to cut costs, build them in way that is cheap to manufacture (not necessarily poorly bulit) but difficult to replace without swapping entire assemblies or units).I've love to see an article on repair costs and how those are impacting insurance rates. You almost need gap insurance now because of how quickly cars depreciate yet remain expensive to fix (orders more to originally build, in some cases). No way I would buy a CyberTruck - don't want one, but if I did, this would stop me. And it's not just EVs.