[HELP] Negative Ackerman Steering Geometry

[Block_Smarts Lego Technic]

Hi,

I'm pretty sure this is Negative Akerman steering geometry.

If your know how to fix this problem please speak up!

Here are some more pictures of the steering setup.

Thanks for your help!

[Jeroen Ottens]

Just reverse the setup... Imagine that the rear wheels are in front of the vehicle and the Ackermann is correct.

[Block_Smarts Lego Technic]

Just reverse the setup... Imagine that the rear wheels are in front of the vehicle and the Ackermann is correct.

Im not sure I understand, do you mean switch the rear axle with the front?

Sorry if I misunderstood.

[Kiwi_Builder]

In a way. So if the steering system is in front of the steering axle at the moment then swap it over so that the steering system is behind the axle. Same as if it's the other way around, if the steering system's behind the steering axle then swap it so that it's in front of the axle

[MaxSupercars]

No... you should put the steering rod behind front axle not in front of it...

Max...

[Zerobricks]

Your steering point position is almost correct, but the links should be straight... The steering point and the point at which steering link is atatched should be placed in a way so that when a line is drawn through them it should pass the center of rear axle.

[Nalyd997]

So basically what you need to do is just take the front axle off (intact) rotate it 180 degrees and the reattach:)

[1974]

Like this :

Cheers,

Ole

[Nick Barrett]

If it's a modern high performance car you may as well leave it as it is; that is how they're set up these days to counter the greater slip angles of the outer wheel when cornering fast.

[Jeroen Ottens]

Sorry for not being more clear with my first comment. Kiwi Builder made it more clear I hope.

If you take of the whole frontaxle, rotate it such that it faces backward (with the steering rack behind the frontwheels) and then put it back on it will work.

Ole's picture shows an approximate Ackermann setup, in real life the setups typically have the linkage setup that you have, moving the steeringrack forward or backward (and adjusting the length of the links to keep the wheels straight) will also change the difference in steering angle between the two wheels.

With some pretty fancy goniometrics you could calculate what the ideal ratios of the linkages should be, but as Nick Barrett already pointed out, in practice the engineers do not aim for the perfect Ackermann geometry, but optimize for other handling parameters (like the ability to corner fast).

[Block_Smarts Lego Technic]

Thanks for you help everyone! It certainly helped me. I hope it can help other users, also!