Mercedes identifies correlation issues between sim and on-track performance
Mercedes has identified an area of its simulation models back at the team’s factory that could be a correlation weakness to address, according to technical director James Allison.
The first three races of the season have seen flashes of strong pace from George Russell and Lewis Hamilton, but a best finish of fifth place in the season-opening Bahrain Grand Prix. Both drivers retired from the last race in Melbourne where Allison again says the car was looking competitive for a spell, and he believes there is an aspect of the correlation between factory and the track that needs improving.
“In simple terms, yes [there are correlation issues],” Allison said. “There are always correlation issues in every year in every team and there always will be correlation issues between what you see in the factory and what you see on the track, because the factory is a sort of reduced version of reality. It is not the same as driving a car on a real track on the actual asphalt of the actual circuit with all its infinite detail and complexity.
“You have simplified models back here in the factory and those simplified models are powerful for steering you one way or the other. But all of them have their shortcomings and all of them have their correlation issues. In large measure the models that we have, the simulation tools we have, are amazingly good at keeping us on the straight and narrow and guiding us towards more lap time. The devil’s always in the detail.
“In the area of the high- to low-speed balance, we could do with some improvement in that area of the models, because there we have some difference between what we are seeing on the track and what we are seeing back in virtual world. And those differences, if we can bring them closer together then it just allows us to be more accurate with the projections we make back here address the things that we believe are holding the car back.”
Another area Allison has identified as a weakness at Mercedes is when the track temperature increases.
“Almost no setup changes occurred between FP3 and qualifying [in Australia],” he explained. “We take fuel out of course, we turn the engine up to 11, all those things. But no significant difference on setup because we felt we got the car in a decent window in FP3 and that was reflected in the time sheets.
“But we are starting to see a pattern emerge that most weekends we have a period where we are feeling good about the car, confident about the car, but then in the paying sessions, in qualifying and the race, that slips through our fingers.
“If we were trying to draw that pattern together, then probably the strongest correlation that we can make at the moment is that our competitiveness drops when the track is warm, when the day is at its warmest and therefore the tire temperatures rise with those of the track.
“The times when we have been at our best have been all in the sessions which are the coolest and so that gives us some clues about what we need to do as we move forward from here. But from FP3 to qualifying in Melbourne there was not a setup change.”