An unfair comparison between a BruteForce2 Direct Drive Steering Wheel and a Logitech G27

It might be true that with enough dedication and talent you can pilot a Logitech G27 to the top of the iRacing charts.  But if you want your sim driving to be as close to real life as possible, you should try a direct drive wheel.  In terms of excitement and realism, the OpenSimWheel in a completely different league to the G27.  It probably won’t work with your favorite console racing games.  It will definitely cost a lot, which might be hard to justify.  However, the OpenSimWheel direct drive AC servo wheel is just so much more enjoyable to drive.  It makes sim racing a whole lot more realistic, with an abundance of steering feedback and texture.

I built a direct drive wheel because I was looking for a better quality wheel than the G27, and desired a greater level of detail and torque.  I wanted more realism than a flimsy plastic wheel with weak, notchy feedback could deliver.  My G27 wheel was sloppy and tired from 100 hours of use.  After improving the pedals with a load cell the wheel was the weakest part of the package.  If money was no object, the Leo Bodnar wheel would be a great choice, but there was no way I could justify spending many thousands of dollars on a wheel.  The Accuforce is less expensive than the Bodnar, with mixed reviews compared to the OSW/Bodnar wheels.  I’m sure there will be other direct drive wheel choices available soon.

I like a good DIY project, so I went with a variation on Beano’s Bruteforce 2 project.  My goal was to keep the cost as low as possible.  I cut costs significantly by using a non-standard AC servo motor/encoder combination, building my own motor mount, wheel clamp, and servo drive enclosure.  It was a lot of work, and not for the less-determined.  I was able to keep the total cost under 700 USD, and I reckon that’s money well spent.  Here’s a link to the wheel I built.  If you don’t want this level of DIY, the standard Bruteforce 2 build with a Mige motor would be much easier.

You might be wondering how different a direct drive steering wheel really is, compared to the less expensive Logitech offering?

In terms of quality and the range of forces detail you can feel, there is a big gap.  For an immersive driving experience, with a wheel that feels lively and realistic, direct drive is a huge improvement from the G27.  Now that I have been using my OSW DD for a few weeks, here are some thoughts on how it’s different from my old G27.  It’s not a fair comparison with the G27 costing less than $240, but I won’t be using the Logitech wheel again.

Logitech G27

Not very expensive, but you get plastic for your money.  Costs $240.

Torque range approx 0.5-2.5nm, if you’re lucky.  It won’t move with minimal torque levels due to backlash and friction from the plastic gears.  Cogging sensation due to cheap and weak motors, along with a plastic gearbox.  Plastic gears and budget bearings develop slop quickly.

Plastic cogs inside the Logitech G27 steering whel

Large deadzone when centred, with a sloppy feel and complete lack of force feedback when the wheel is in the centre.

Maximum steering range is limited to 900 degrees by a plastic slider.

G27 wheel unbranded motor and plastic steering rack

Slow rotational speed because of the small motor, gearbox and backlash.  Difficult to catch slides because you feel the movement after the fact – not a problem if you are an alien, as you’ll never go into a slide.

Small dynamic range available, a bump and a whack against a curb feel much the same.  Difficult to tell how much force the steering wheel is trying to convey because the range is small, movement  is slow, and friction is high.

Lightweight plastic construction, easy to lift and move around.  Comes with pedals and shifter that can be modified into something ok.  Buttons on the wheel, with paddle shifters for sequential.  Buy it, plug it in, and drive.

Logitech software works well on PC and some consoles.

BruteForce 2 / OpenSimWheel (using MMOS firmware on STM32F4 Discovery)

Pricey, made to last. Costs $1000-$6000 depending on how DIY.  I built one for about $700 USD, but it was completely custom and time intensive.  There are some guys selling reasonably straight forward DIY kits for $1000+ on the iRacing forums.

Wooden direct drive wheel ffb osw brute force 2 steering wheel with ioni servo drive

Torque range 0-20nm, depending on the motor you choose.  The Mitsubishi ac servo motor I’m using produces 15nm maximum torque, and I think it’s ideal.  No minimum level of torque in order for it to move.  No friction, no cogging.  Smooth turning.  No play in the bearings, no flex.

Mitsubishi Melservo HF-SP102 AC Servo Motor

No deadzone, no delay or backlash before the torque kicks in.  Force feedback is consistent and smoothly delivered wherever the wheel is rotated.

Unlimited configuration of steering angle range (no mechanical stops, they are provided by motor torque).

High speed, rapid change of direction, no backlash, steering wheel directly mounted to the motor shaft.  Easier to catch slides because you can immediately feel the car shifting and unweighting the tyres.  iRacing used to cause  oscillation when you’re idling in the pits, but this has between fixed in recent updates and is no longer and issue.

Large dynamic range.  Subtle movements are delicate and detailed, and big thumps make my couch rig shake.  Incredibly satisfying with a very lively feel of what the car is doing.

Wooden handbrake and sequential shifter withOSW Direct drive wheel

Heavy, high quality, industrial grade motor, made to last for a very long time.  The AC servo motor is designed to be run in a factory constantly, and it doesn’t break a sweat when used as a steering wheel.

Requires an aftermarket steering wheel and mounting clamps.  Requires an additional shifter and pedals.  The Discovery USB controller board in the OSW can also be used as the controller for pedals, shifter and buttons.  Buttons on the wheel require either wireless or a coiled wire race car style connector.

Major project, you’ll need to buy parts, wait for them all to arrive, spend ages setting it up, customize it and then you can go driving.  Frustrating if you have missed a wire when you are building it, but unbelievably satisfying to drive with once you’re up and running.

Requires an extra box for the servo drive unit (containing Granite Devices Ioni and Disco board) and two cables connected to the motor.

On the software side of things, the OSW uses the MMOS firmware which allows it to appear as a standard DirectInput wheel in Windows, works with most games (hopefully with Dirt Rally support this week).  The configuration utility is not as user friendly, but only needs to be setup initially.  The Ioni servo drive allows a hardware knob to allow on the fly adjustment of the maximum torque.

AC Servo motors create a lot of EMI, so you will likely need to play around with grounding wires to eliminate noise if you use load cell pedals.

Wrapping up

The difference is night and day.  It’s like going from a plastic toy wheel to a setup you’d imagine a pro racing team would use.  A G27 can be driven fast by a competent iRacer, but the satisfaction and immersion from using a direct drive is immense.  It not unusual for people to start laughing or grinning uncontrollably when they start driving with an OSW direct drive wheel, they are so different to a non-direct drive wheel.

If you’re going to use it a lot, then I think it’s a good investment.  If you plan to use this as a substitute for track days in a real car, with all the running costs that go with it, then I think it’s justified.  Reducing the number of times you drive a real car, and substituting it with sim racing time will save a heap of resources and money.  Real race cars aren’t exactly sustainable, sim racing could make your footprint on the earth a bit lighter.  Btw, if you want some competitive racing, you should definitely try out iRacing.  There is a huge amount of support for the OpenSimWheel/BruteForce wheels on the iRacing forums, I’d recommend joining.

If you already own a G25/G27, then you can put the pedals and shifter to good use with an OSW direct drive wheel.  The MMOS firmware with the OpenSimWheel project allows you to connect your G27/G25 shifter and pedals to the same controller used for the direct drive AC servo wheel.  I also built a separate sequential shifter and handbrake for Dirt Rally, and it works great.  The only catch is, you’ll soon want a high end pedal set to match the quality of your direct drive wheel.  I’m currently building a set of hydraulic+load cell pedals from scratch.

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