Polestar Racing: Accuracy to the second or third decimal place



Race car engineering is a notoriously competitive environment in which the minutest aspects of design and the smallest adjustments can separate the winners from the losers. To stay on top of the game, Polestar Racing uses Adams to evaluate different vehicle designs in critical areas of the track such as corners.

Adams/Car allows Polestar to accurately simulate the performance of any particular vehicle configuration in a corner and by simulating many configurations the team can determine which one is the best for a particular track. Most of the groundwork is laid in the winter months, when it is preparing its cars for the next season. While the team typically has many different ideas to improve race performance, they can only spend four or five days every six weeks at the test track in southern Spain. The schedule is intense and the number of vehicle configurations that they are able to test is strictly limited. The team performs around 3,000 kilometers of track testing each winter with the new car compared to the 150 kilometers or so that each driver covers in the course of a normal race weekend. While Polestar had long used simulation to test components, the real game changer was Adam’s ability to predict the performance of the complete vehicle and vehicle subsystems. Working in the Adams/Car environment, automotive engineering teams can exercise their vehicle designs under road conditions, performing the same tests they normally run in a test lab or on a test track, but in a fraction of the time.

The Polestar team found the correlation between Adams/Car simulation and physical testing to be very high. When the team compared simulated to measured roll angle or lateral or longitudinal acceleration, the results match up to the second or third decimal place.

Before Polestar used Adams/Car they found that only 40 percent to 50 percent of what they tried at the test track turned out to be effective. Since they began using Adams/Car, 80 percent to 90 percent of the ideas that they try on the track succeed. By enabling the team to try out ideas on the computer first, they are able to evaluate many more ideas than in the past and spend scarce time at the track just on ideas that they are nearly certain will work. As an example, the Swedish Touring Car Championship changed tire suppliers a few years ago. All of the teams scrambled to better understand the behavior of the new tires. Polestar used Adams/Car to explore the effect of variables that influence the behavior of the tire on the full vehicle performance. Polestar discovered that vehicle performance was optimized at two very different combinations of tire pressure and camber. Both of these combinations were equally fast but there were major differences in the way the vehicle handled, particularly in the degree of oversteering and under-steering. After noticing this phenomenon in simulation, Polestar engineers tested it out on the track and found that it was accurate. They used this knowledge to select one set of conditions or the other depending on which type of behavior was best suited for a particular track. On several conditions they even changed the conditions in midrace.

The Polestar Team has found Adams to provide a significant competitive advantage – enabling them to truly understand their vehicles and allowing them simulate the car for every configuration and track condition they can imagine.