This is an RC car web site but I found the diagrams and animations really easy to understand. I especially like the fact that the writer has gone to the trouble of illustrating how to calculate Ackerman and a toe-in, toe-out version.

http://www.rctek.com/technical/handling/ackerman_steering_principle.html

My first recollection of Ackerman was in 1965, when I was 10.

I had an Airfix slot car set for Christmas as it was cheaper than Scalextric. (Times were hard )
A Vanwall and a shark nose Ferrari.

It said on the box "Full Ackerman Steering" and I had to get my older brother to explain it to me.

Cheers
Paul G

and.........................................

The bit no website or book will tell you is true Ackerman geometry can't be applied to rack and pinion steering.
Classical Ackerman only works where the steering uses a centre track rod --- ie a lorry style beam axle or a 1950's style suspension with a steering box and idler arm.


To get an ackerman effect ( toe-out on turns ) on a book style Locost style chassis the steering rack positioning of the donor Ford should be copied, that is the centre line of the steering rack set a few inches to the rear of an imaginary line joining the centres of the outer track rod ends.

[Edited on 3/8/09 by britishtrident]