Encompassing the latest developments on tire mechanics, this definitive third edition combines theory, guidance, discussion and insight in one comprehensive reference. In this well-known resource, the author, leading tire model expert Hans Pacejka, explains the relationship between operational variables, vehicle variables and tire modeling, taking you on a journey through the effective modeling of complex tire and vehicle dynamics problems.
What is Pacejka's Magic Formula. Pacejka's Magic Formula is used to estimate tire forces due to slip angle and ratio. For more information on the basic formula(e), see the Pacejka Magic Formula page here. This page deals only with the implementation in Racer.
The Pacejka / Magic Formula (MF) equations were conceived to fit the data gathered from experimental tests with real tires. The equations can then predict the behavior of each specific real tire with great precision.
Real Pacejka/MF data sets are heavily protected intellectual property of the tire manufacturers. However, when used in video games where gameplay is important, the Pacejka curves can be fine tuned in a variety of ways in order to achieve the desired result. This guide explains how each parameter of the Pacejka ’94 specification affects the resulting curve, as well as the typical range for the values.
Longitudinal Force Pacejka ’94 Longitudinal Force parameters: Parameter Role Units Typical range Sample b0 Shape factor 1.4. 1.8 1.5 b1 Load influence on longitudinal friction coefficient (.1000) 1/kN -80. +80 0 b2 Longitudinal friction coefficient (.1000) 900. 1700 1100 b3 Curvature factor of stiffness/load N/%/kN^2 -20. +20 0 b4 Change of stiffness with slip N/% 100. 500 300 b5 Change of progressivity of stiffness/load 1/kN -1.
+1 0 b6 Curvature change with load^2 -0.1. +0.1 0 b7 Curvature change with load -1.
![Pdf Pdf](http://upload.wikimedia.org/wikipedia/commons/thumb/5/50/Magic_Formula_Curve.png/440px-Magic_Formula_Curve.png)
+1 0 b8 Curvature factor -20. +1 -2 b9 Load influence on horizontal shift%/kN -1. +1 0 b10 Horizontal shift% -5.
+5 0 b11 Vertical shift N -100. +100 0 b12 Vertical shift at load = 0 N -10.
+10 0 b13 Curvature shift -1.