The radical steering innovation being refined in motorsport

It doesn’t take an engineer to recognise that racing cars have changed a great deal since the dawn of automobile racing. In regard to safety, modern cars are virtually unrecognisable. But many core tenets of those very earliest racers have remained the same, even as the rise of electrification and the push towards automation has brought increased complexity.

Until recently, steering systems could be counted among those elements. A mechanical connection between the wheels directly manipulated by driver inputs had been a design prerequisite since day dot. But German company Schaeffler-Paravan changed all that with its steer-by-wire system, which does away with the need for a steering column or any mechanical connection to the steering.

It instead transmits steering commands digitally utilising sensors and cable, working in a fashion akin to a driving simulator, and is now being used in competition in the DTM, the national-level GTC Race series and Germany’s national rally championship. For Schaeffler-Paravan’s chief of technology Hubert Huegle, it’s a “historic” undertaking.

“After 120 years we remove the steering column,” he says. “I think not everyone is clear what we are doing here.”

The steer-by-wire story

The system was originally devised by Roland Arnold to allow disabled people with restricted motor skills or lower residual strength to drive safely. The idea was germinated by a chance meeting at a motorway service station with a woman struggling to get her quadriplegic husband into their car, and her wish for him “to ride next to her in the car and not be transported like a piece of luggage in the boot”.

“People can also drive a wheelchair with a joystick, why shouldn’t that also be possible with a car?” says Arnold, who started Paravan in 1998. He has since built a “holistic” package that includes its PR50 wheelchair that can be used as a seat, a lift device to help disabled people get into their cars, and the so-called Space Drive system – of which steer-by-wire is a part – which also allows the brakes and transmission to be controlled electronically.

The Schaeffler-Paravan steer-by-wire technology allows people with disabilities to drive safely on the road

Photo by: Schaeffler Paravan

It is anticipated that the steer-by-wire technology will form a significant part of automated driving solutions in the future. So far, it boasts over a billion miles of accident-free usage on the road thanks to a triple redundancy mechanism that uses two safety systems for back-up in the event of one component failing.

As Arnold points out, “for people with the most severe impairments who drive with a joystick or accelerator-brake slider, the system must be absolutely fail operational”.

Space Drive is the only such system homologated for road use, having had to pass stringent quality-standard tests ECE-R79 and ECE-R13 to gain approval.

“I’m completely relaxed when the cars are running on-track,” says Huegle, who was first introduced to the technology while at HWA and working on the hydrogen-powered HYRAZE League concept that featured steer-by-wire. “This is a proven technology.”

“It is super safe,” confirms Muecke Motorsport boss Peter Muecke. “We haven’t had one single problem, one single failure.”

In 2018 Paravan launched a joint venture with Schaeffler, an innovation partner to the DTM that previously partnered with Audi on its Formula E drivetrain, with the objective of scaling up Space Drive’s usage by OEMs. Arnold wants its latest iteration using lessons from motorsport, Space Drive 3 AddOn, to reach “the next level in series production” and describes its Schaeffler partnership as “the next logical step” in doing so.

“Our goal is to be a part of the market in 2025-26,” Huegle explains. “We want to show that our system can be added onto whatever vehicle, not only for road cars.”

Arnold adds: “Space Drive 3 will provide the technological basis for the development of an integrated system. This is the prerequisite for every OEM when they install the system in series production of future vehicle generations.”

Paravan founder Roland Arnold wants to see Space Drive technology used in more road cars and in other industry sectors

Photo by: Gruppe C GmbH

The joint venture was, however, unrelated to the decision to put steer-by-wire through the rigours of competition on the track. That was pushed by Arnold, who deemed it “the most suitable development platform and essential”.

After a first demonstration lap on the Nurburgring Nordschleife was completed in 2019 by Rahel Frey aboard an Audi R8 LMS GT3, the system was fully operational in race trim the following year and, alongside outings in GTC, it completed the Nurburgring 24 Hours with a Space Drive Racing Porsche Cayman GT4. Last year, it again finished the legendary enduro with a GT3 Mercedes also prepared by circuit expert W&S Motorsport.

The same year it was introduced to the DTM in three different cars: Maxi Buhk’s Muecke Mercedes, Timo Glock’s Rowe Racing BMW M6 GT3 and the Abt Audi of Sophia Floersch. Huegle says this was “to show that our system with more or less the same hardware can work in different cars, even in different concepts”, but it has consolidated its DTM activities on working with Muecke this year rather than splitting its capacity and budget.

“I know [the Mercedes] pretty well because I designed it completely,” explains Huegle.

Schaeffler-Paravan engineers are embedded within Muecke’s operation to the extent that the veteran boss says “we are one team, literally” and their work in collating the data logged through racing has allowed for constant development of the steer-by-wire system.

Huegle says: “To optimise the product from a lightness [perspective], this is a base development step, so we did this for sure. One of the bigger steps is to transfer the feeling, what the driver feels normally via their steering column, via an ECU in data to the driver. This is the technology we develop and there is a big step between last year’s software and this year’s software. The development out of these datas, it’s the biggest benefit.

“The next thing for example is the steering velocity, nobody steers faster than a racing driver, therefore we had to introduce some new components, but it’s normal. There is always room for improvement.”

Mercedes GT3 equipped with steer-by-wire finished Nurburgring 24 Hours in 2021, and reduced the forces exerted through the wheel onto the driver

Photo by: Gruppe C GmbH

The user experience

Now aged 75, Muecke admits that he’s “been involved in motorsport for such a long time that it becomes a little bit of a routine”, so jumped at the chance to be involved in developing the technology – both to exercise his curiosity and to explore its potential to yield a performance advantage in a GT3 formula where cars are tightly homologated. His team’s involvement in steer-by-wire’s development, he says, “is really a massive joy”.

“You are always looking out for new opportunities to improve your car, your set-up and all the technical possibilities,” he says. “It was clear to me that we just had to do this. Normal things, I have had enough in my life, believe me. But this really is next level. A highlight? Yes, most certainly.”

Having sampled the system for himself before signing up to run steer-by-wire in 2021, Muecke believes it brings “a clear advantage for the driver” on certain tracks.

“You aren’t exposed to so many impacts as a driver and therefore the handling of the car is more neutral because it doesn’t respond to every bump,” he says.

Buhk took the system’s first podium at the Norisring last year, ironically at the track where his team “had the biggest question mark”.

“We didn’t know how good the steering would be in the hairpins and with low grip on the track,” he says, “but in the end it felt really good. It’s actually quite nice to drive over kerbs for me as an old guy [not that old at 29! – ed] because you don’t have the knock-back in the steering.”

The 2013 Spa 24 Hours winner says development on the force feedback is “improving all the time” and that the project’s primary focus now is on fine-tuning small details.

Buhk and the Mucke team work closely with Schaeffler-Paravan engineers, with force feedback a key area of focus

Photo by: Alexander Trienitz

“For me we are there, it’s not like we’re a few seconds off because of the steering,” explains Buhk, who on a regular DTM weekend doesn’t “spend too much thought about the steering which is working”.

“We are really working like all the other teams on the set-up side getting the tyres to work, working on the race set-up. We are really here like every other race team. It’s not a big difference, you jump into the car and you just drive.”

Both Buhk and Muecke praise the level of customisation in the system, with differing levels of force feedback available depending on the driver.

“One of the advantages of our system is that even by mapping switches I can change the ratio,” Huegle explains, “so the flexibility of the system is incredible.”

“It is astonishing what they are actually able to do,” adds Muecke. “When we say, we would like to have this or that a little bit different, you get it. They plug their laptop in and they programme it and all of a sudden, it really is different! Everything has been implemented, the response is there.”

The future

Huegle is clear that Schaeffler-Paravan’s involvement in the DTM has achieved its aims in improving awareness around the steer-by-wire technology and convincing potential users of its integrity.

“At the end, this technology will help to get the autonomous drive in a way that everybody trusts these cars,” he says. “There will be a time when nobody is thinking about [the safety of] an autonomous driving car.”

Arnold agrees: “The racing programme has absolutely achieved its goals, without which we would never have achieved credibility. The findings are very important for our development process. The advantages are already obvious.”

Hubert Huegle says the motorsport programme has achieved its goals in convincing potential users of its integrity

Photo by: Gruppe C GmbH

Muecke is chief among those who have been totally convinced of this and is excited by the project’s “enormous” potential for road use.

“There will be so many possibilities for the automation of driving in the future that we really have to say we are working on a part of history,” he says. “This is the automotive future. In the long term, I believe that from this development things will emerge that will mean safety for normal drivers out there on the road. What better place could there be to develop and to test such a system than in racing? What is working here, will work on any normal road.”

Steer-by-wire is set to be in all DTM Electric cars when that concept, led by Schaeffler, becomes reality in 2024. But it’s in rallying – where the technology is being developed by Armin Schwarz, with its next outing planned for October’s Three Cities Rally in lower Bavaria – that its latent potential for motorsport most excites Huegle.

“From my point of view the rally business is even more interesting,” he says. “The potential of a steer-by-wire in rally is even bigger because I can filter out all of these big bumps where nobody needs all the pain on their arms or their joints. It’s not necessary because our system can take all these big loads and give him just the feedback he needs.”

It’s clear that we will be hearing much more about Schaeffler-Paravan’s steer-by-wire system in the coming years. And, in the not too distant future, it might perhaps come as standard in your daily driver…

The technology also has significant potential in rallying, where it is being developed by former WRC driver Armin Schwarz

Photo by: Sascha Doerrenbaecher