Hi, Yes, its another mad physics discussion that I'm starting. The pacejka model for tyre behaviour consists of 4 curves - Tyre Longitudinal Force: Slip Ratio Tyre Lateral Force: Slip Angle Aligning Moment: Slip Angle Normalized Force: Slip Ratio My source: (Correct me if a part of the model is not described on that page) I think something is missing here. Surely, the aligning moment is not a function of slip angle alone, but of slip ratio too? May 29, 2018 - The Pacejka / Magic Formula (MF) equations were conceived to fit the data gathered from experimental tests with real tires. The equations can. ![]() If you have a tyre with a high slip ratio, it is twisted a bit in the longitudinal direction. If you try to get it twisted in the lateral direction at the same time, surely you should be having greater resistance (aligning moment). This would be because the longitudinal slip is trying to 'twist the tyre into a straight line'. This could also explain why so many sims struggle with low speed tyre physics. At low speed, you have a greater longitudinal slip and when you try to turn at the same time it feels awkward. You slide too much, because your slip angle is much higher than what it feels like it should be (I'm just guessing here). Could we do an experiment in the garage/back yard to test this? I have some tyres on rims lying around in there but I don't know where to start. I don't think I'll get enough force in there to twist the tyre significantly and I don't think I'll actually be able to calculate/estimate aligning moment. Suggestions are welcome though. This should make for interesting discussion. Disclaimer: I do not know how the LFS model works at the moment, and as such I cannot know that this is not already in there. I am also not sure if it is in other sims and I am not sure my claim is correct. Quote from axus:Hi, Yes, its another mad physics discussion that I'm starting. The pacejka model for tyre behaviour consists of 4 curves - Tyre Longitudinal Force: Slip Ratio Tyre Lateral Force: Slip Angle Aligning Moment: Slip Angle Normalized Force: Slip Ratio My source: (Correct me if a part of the model is not described on that page) I think something is missing here. Surely, the aligning moment is not a function of slip angle alone, but of slip ratio too? If you have a tyre with a high slip ratio, it is twisted a bit in the longitudinal direction. Vip weapons crossfire hack. If you try to get it twisted in the lateral direction at the same time, surely you should be having greater resistance (aligning moment). This would be because the longitudinal slip is trying to 'twist the tyre into a straight line'. This could also explain why so many sims struggle with low speed tyre physics. At low speed, you have a greater longitudinal slip and when you try to turn at the same time it feels awkward.
0 Comments
Leave a Reply. |