"In this section we are going to discuss vehicle dynamics. Vehicle dynamics is a term used to describe how a car
responds to a drivers control inputs.
All cars respond to the drivers input following the laws of physics. The cars in the sim are designed to
respond in the same way as real cars.
Your ability to get the car around the racetrack is dependant on the capability of the car but its even more
dependant on your ability to control the car, having a good understand of how to control the car whether sim or
real is essential to being a good driver.
Whether you're racing or simply driving to work there are three basic control inputs or commands a driver can
use to make the car perform
Learning to effectively use the controls is the key to driving well, in fact its even more important in a Sim as
the feedback you get is drastically less in the sim than in a real car, you have no seat-of the-pants forces to
tell you the result of your inputs in the sim and have to rely on visual and limited steering feedback to asses
the effectiveness of your actions, thus the more knowledge the driver has, the more efficient they will be in
controlling the sim car.
All of the commands you give the car with these controls are transmitted into action through the tyres,
understand how the tyres work is the first step.
The engineers at iRacing
been very careful to accurately replicate the way real tyres behave in the simulation.
There are three directional forces the tyre is subject to;
The tyre's grip can be devoted to any one or a combination of these forces to accomplish a drivers command, a
tyre interacts with the surface of the track by distortion of rubber moving over the surface, causing a small
amount of slip, this slip referred to as the slip angle while cornering determines the effectiveness of the
tyres contact patch.
Too much slip and you lose grip
Not enough and your below the potential of the tyres.
In part two of vehicle dynamics
we'll take a look at how tyre grip is influenced by load transfer in your car and will show you some ways to practice
what you have learned..."