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Ackerman,
Great screen name.... when you type and turn left do you have to type faster with your right hand??? .....LOL
Front wheel movement?
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[quote:3029eac25e="speedsense"]The location of the steering tie rod at the upright, it's relationship to the "kingpin" (this is the turning pin that allows the front upright to swivel) determines the ackerman.
There are unequal length a arm suspensions that have zero ackerman.[/quote:3029eac25e]
Do F1 cars use kingpins or are you that old? No disrespect intended.
This phenomenon is also known as "toe out on turns".
There are unequal length a arm suspensions that have zero ackerman.[/quote:3029eac25e]
Do F1 cars use kingpins or are you that old? No disrespect intended.
This phenomenon is also known as "toe out on turns".
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[quote:65fb11c642="mustang6172"]Do F1 cars use kingpins or are you that old? No disrespect intended[/quote:65fb11c642]
"kingpin" is another (although somewhat uncommon) term for an "upright" or "steering knuckle." It comes from what would technically be termed a kingpin, i.e. the almost-cylindrical shaped piece that you are thinking of, but the name stuck around. Also, the steering axis is known as the kingpin axis, and its angle to a vertical is called kingpin inclination, so it is not exactly an "old" or "unused" word.
A bit of clarification, Ackermann geometry is really only useful at low speeds (where turn geometry dominates--think circles), at higher speeds (i.e. more cornering force => more lateral load transfer) tires develop significant slip angles [the angle between where the tire or rim is facing and where the contact patch is facing--you can also think of it as the angle between where the tire is facing and where the tire is heading]. At higher lat. load transfer, the maximum cornering force from the inside tire peaks at a lower slip angle than the outside tire (which has nearly all of the weight on it). This means that Ackermann geometry would be hurting the maximum cornering force of the car, so parallel steer or anti-Ackermann (outside wheel turns more than inside wheel) is used.
I would guess that anti-Ackermann is used on F1 cars (or at least parallel steer) given the high lateral loadings, but I could not see which wheel was turning more in the video (you'd be surprised how hard it is to see even if the car was right infront of you).
"kingpin" is another (although somewhat uncommon) term for an "upright" or "steering knuckle." It comes from what would technically be termed a kingpin, i.e. the almost-cylindrical shaped piece that you are thinking of, but the name stuck around. Also, the steering axis is known as the kingpin axis, and its angle to a vertical is called kingpin inclination, so it is not exactly an "old" or "unused" word.
A bit of clarification, Ackermann geometry is really only useful at low speeds (where turn geometry dominates--think circles), at higher speeds (i.e. more cornering force => more lateral load transfer) tires develop significant slip angles [the angle between where the tire or rim is facing and where the contact patch is facing--you can also think of it as the angle between where the tire is facing and where the tire is heading]. At higher lat. load transfer, the maximum cornering force from the inside tire peaks at a lower slip angle than the outside tire (which has nearly all of the weight on it). This means that Ackermann geometry would be hurting the maximum cornering force of the car, so parallel steer or anti-Ackermann (outside wheel turns more than inside wheel) is used.
I would guess that anti-Ackermann is used on F1 cars (or at least parallel steer) given the high lateral loadings, but I could not see which wheel was turning more in the video (you'd be surprised how hard it is to see even if the car was right infront of you).
