Simulation techniques have become a vital tool in vehicle development, enabling shorter development time, fewer prototypes, and reduced costs. When used in motorsport, the advantages gained using sim can literally make the difference between winning and losing.
It is in motorsport where British start-up Dynisma first saw an opportunity. “I spent a lot of time thinking about how to do a better job than what is out there, and I founded Dynisma specifically for the purpose of bringing these ideas to market”, explained Ash Warne, the company’s founder, chief engineer and CEO. Warne’s background is in driving simulators, having spent a decade with the McLaren and Ferrari F1 teams. He returned to the U.K. in 2017 and founded Dynisma.
“The idea was always to make motion generator technologies more accessible and increase the capabilities of what’s available on the market,” he told SAE Media. His first 18 months with the start-up were focused on testing his theories of what he believed was possible. “Then we built our plan – to disrupt the automotive and motorsport simulation markets with new technology,” he said. In early 2019 he built a development team and engaged with investors.
This enabled Dynisma to develop its first product, a simulator named DMG-1 (Dynisma Motion Generator 1). The Ferrari F1 team used a version of DMG-1 to hone its racecars for the 2022 season. Versions designed for road-vehicle dynamics, ride quality, and NVH simulation benefit from the racecar-sim technology. There are also developments focused on electric and automated vehicles.
Six degrees of sim
The DMG-1 demonstrator at the company’s facility in Bristol, U.K. uses a single-seater tub, set up like the cockpit of a formula car, with a steering wheel and controls. This is mounted on Dynisma’s motion generator.
“Another enabling technology that we’ve developed is this split system. We have a six-degrees-of-freedom system at the top – and any rigid body in the universe can move in six degrees of freedom,” Warne noted. “So, we can translate in three degrees of freedom, and we can rotate about them. That leads to this minimum requirement of having these six degrees of freedom, in order to accurately render the motion.”
Because it’s a ground-based vehicle, the larger excursions are predominantly in the horizontal plane, Warne said. That’s why the simulator design has the two-stage system with six degrees of freedom on top—it connects the driver as directly as possible in all degrees of freedom to a source of movement and vibration. This is augmented with a triangular lower section, which gives additional lateral, longitudinal and yaw capability, he explained.
For the visual projection, Dynisma uses five projectors on a curved screen with a 240-degree arc. The data gathered from test tracks that is used to generate the imagery is taken from lidar scans and an inertial measurement unit. Objects surrounding the road are all placed “with millimeter accuracy,” Warne said, adding that vertical inputs coming into the car model are also derived from lidar scans.
The Dynisma simulation techniques are designed to overcome what the company sees as shortcomings in existing simulation technology. Warne’s team works with several technology partners, including ST Engineering Antycip for projection technology, rFpro for graphical rendering and road/track models, and Canopy Simulations who provide vehicle modelling solutions. Dynisma customers can also use their own software choices in its simulators.
Low latency, wide bandwidth
The key to Dynisma’s simulation technology is the low latency the system provides, according to Gavin Farmer, the company’s commercial manager. “The closest analogy that we have in that regard is music,” he said. “If a musician is playing to a monitor, they can discriminate 10 milliseconds. If there is a delay of more than 10 milliseconds on what’s being played back to them, it’s noticeable to them.”
Drivers may or may not appreciate the reduced latency, Farmer noted. “It’s one thing whether or not they [drivers] can discriminate it,” he said. “The other thing is you have just unequivocally delayed things in being able to respond. This can be important in the vehicle dynamics situation because they’ve put that input 10 milliseconds later than they possibly could have done in driving the car.”
“We see that in our Formula 1 model, when we do the demo with the F1 car,” said commercial director Jason Baker. “You have to catch the oversteer moments really quickly, but you can catch them. In other simulators, customers must build in more of an understeer setup, so that they don’t have to experience it. Otherwise, the simulation constantly needs re-setting because the drivers can’t catch the car when it goes, and they end up crashing.”
With three to five milliseconds of latency, Dynisma claims the lowest latency on the simulator market. Motion bandwidth is also claimed to be 50% wider than competitors’ systems. The DMG-1’s high motion bandwidth, low latency, and “driver-in-the-loop” functionality, have opened further developments in the variant designed for road-vehicle driving simulations. Its DMG-X product is aimed at testing ride comfort, NVH and driver development.
The DMG-360 product represents the pinnacle of Dynisma’s development to date, according to Warne. The “360” is a reference to its unlimited yaw, which means it is possible to spin in the simulator. It has been developed to accurately represent the limit-handling behavior of cars for both motorsport and automotive applications, as well as improving realism in city driving which encompasses many tight radius maneuvers.
Dynisma’s own product development relies heavily on simulation technology. “When we turn the machine on, there is a multi-body model in the controller that we’ve developed”, Warne explained. “When you drive around in DMG-1 or any of our simulators, there is a mathematical model, a multi-body model running in real-time in the background. It is being executed 4,000 times a second and that is telling us, “OK, if I want to produce this acceleration, what motor forces do I need to use?””
The Dynisma system presents several additional applications, including electric and autonomous vehicles, where arguably, ride quality and NVH may be an even greater issue than they are now. Beyond the automotive arena, applications could include aerospace where the high frequency capabilities of the system are relevant with aerolastic flutter, rotorcraft vibration and even fast jet simulation.
In the sim hotseat
The Dynisma team offered the DMG-1 experience to SAE Media, so I strapped into the DMG-1 motorsport simulator at the company’s Bristol HQ. It’s probably the closest I shall ever get to driving an F1 car. From my years of testing new vehicles as a journalist, I know how a vehicle feels on a range of different surfaces including Belgian pave, for example, and the sensation of driving over a sawtooth kerb on a racetrack.
These were good reference points for my time in the simulator which would first put me on the Spa-Francorchamps grand prix circuit for several laps, then on the U.K.’s Millbrook proving ground, which I know well. My first impression was the level of detail in the projection of Spa. While the image is simulated, the detail is accurate. Feedback through the steering wheel, the feeling of suspension movements, plus the video graphics and realistic sound, all deliver a very faithful impression of driving on the Spa and Millbrook circuits. Crossing a sawtooth kerb provides the expected steering wheel judder, suspension reaction and sound, along with the sensation of speed that you would expect on a racetrack. If I was using the simulator to test a range of suspension settings, for example, the DMG-1 would provide the feedback I would expect from an actual vehicle.
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