I've been writing a non-realistic car physics engine as a learning exercise, using this article as a reference.
I have a car that correctly collides with a terrain and applies the correct suspension forces for each wheel. My next problem is to prevent lateral movement of the wheels. For example, if I drop my car on a slope, it will slide sideways down the slope and then never stop sliding sideways (as there is no friction of any kind).
The linked article says that a "side force" must be applied, combined with the forward force, but it glosses over how that side force is calculated.
Given the collision info for each wheel (intersection normal, etc.) and the information about the car's rigid body, how can I calculate the appropriate side force to apply to the rigid body to prevent sideways motion?