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The above forum contains comments that explain basic anti-Ackermann vs Ackermann quite well in layman's terms.
Tl;dr:
Due to material properties within the tire, every type of tire will have a different slip angle (the difference in traveling direction and the direction the tire is pointed in) preference for maximum grip at different loading conditions. When cornering very fast and turning tightly, the vertical loads on the tires will change, and the tires will want to see a certain slip angle for maximum performance. Ackermann can be applied because pro-Ackermann will introduce more slip angle for the inner tire while anti-Ackermann will introduce less slip angle. Tires can prefer more or less slip angles in a turn. By knowing tire characteristics, the type of geometry can be chosen. Normally, when turning, the inner wheel will normally see reduced loads.
Process for determining type of steering required
- When cornering, there will be weight transfers between the two tires.
- The tire slip data will show us the lateral force that can be achieved with the tire at different slip angles, there will usually be a range of slip angles that will allow for a peak force before dropping off.
- After finding the normal loads on each tire by using the first set of equations in the paper above and the inclination angle of each tire (variables in the inclination angle computation equations were not explained), the raw tire slip data can be put into a software (Optimum T, has free trial). Using the inclination angle and normal load, optimal slip angle to reach peak lateral force can be found.
- If the outer wheel prefers a larger slip angle, then anti-Ackermann should be chosen, vice versa. Due to a larger slip angle arising from a larger turning angle. However, there is another factor affecting the type of steering chosen; tire drag.
- Due to the drag on the outer tire of an anti-Ackermann setup, it will produce a moment that will want to turn the car out of the corner. So usually an FSAE car will choose Ackerman due to the factor of tire drag.
- The example in the paper chose to do an imperfect Ackerman geometry to produce some effects of anti-Ackermann and minimize tire drag. Analysis should then be performed to check if the geometry can turn the smallest bends in the track.
tl;dr: we need tire slip data before we do anything.
Running Anti-ackermann:
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References:
https://www.f1technical.net/forum/viewtopic.php?t=16957
http://www.fsae.com/forums/showthread.php?3825-Anti-Ackermann-Is-anyone-using-it
https://www.quora.com/What-are-the-required-calculations-for-the-Anti-Ackermann-Steering-Mechanism