The Ackerman Effect

[myothercarsa2cv]

So I understand that the inside wheel follows a different arc to the outside wheel when negotiating a corner.

 

What I don't understand is why then there are lots of differing opinions on whether toe in or toe out is desireable, as surely this will have an affect on what arc the wheels follow? For example, with toe in, the inside wheel will act to counteract the motion and for toe out the outside wheel will counteract it? Is the tracking whilst cornering adjustable independent of toe?

[Titanium7]

Simple graphical simulation web site

 

Have a look here

[6speedmanual]

Is the tracking whilst cornering adjustable independent of toe?

 

Only by changing the design / angle of the steering arms.

On a seven it is not realistically adjustable.

On a race car it may be possible to have different steering arms and therefore Ackermann fo different circuits.

 

So why is it said that front toe-in gives more understeer and and toe-out less understeer?

 

Now that is an interesting question, much discussed on BC before.....

 

Peter

[myothercarsa2cv]

Thanks both. Ti7, I've not seen that graphic before, it's quite good. I wonder if ackermann is more important than toe for most situations?

 

I did a quick google for "adjustable ackermann" and it's pretty much all karts and remote control cars! So if I'm understanding it correctly, it could simply be adjusted with a couple of washers between the upright and the steering arm? No need for a new design?

[Tony Whitley]

Ah, Ackerman, not Akkerman. Nothing to do with

then My bad.

[TomB]

Ok clever Blatchat, so what is a Coander Effect exhaust all about?

[Jonathan Kay]

Quoting Tony Whitley: 

Ah, Ackerman, not Akkerman.

Ackermann

 

Jonathan

 

Edited by - Jonathan Kay on 13 Nov 2012 08:53:05

[Nov-07]

More pedantry - it's "Coanda" 😬

See http://www.av8n.com/how/htm/spins.html#sec-coanda and even Wikipedia "Coanda Effect"

Are you thinking of a "blown exhaust" for the Seven 🤔

 

 

Edited by - November7 on 13 Nov 2012 09:19:21

[Tony Whitley]

The exhaust on one of my old cars was like a colander, maybe that was what TomB was thinking of? It made it sound faster.

[Jonathan Kay]

Coandă , but I'm just wondering if that breve on the last letter will survive BC rendering.

 

I think there was a thread about how to explain lift on aerofoils, which included a discussion about how much the Coandă effect contributed.

 

Jonathan

[Jonathan Kay]

Well, that's the answer: the breve doesn't survive BC at all. It's strange when that happens because it looked fine as I entered it.

 

Jonathan

[myothercarsa2cv]

Thanks for the diversion On the subject of exhausts, there was a 4-1 style made in the states back in the 60's that perhaps added nothing but sounds incredible - 'equal length' headers* in to one collector can, but the amount that each header protruded in to the can was staggered a bit like:

__________________

______

______

____________

____________

__________________

 

If that's clear... * If I remember correctly, the length from block to end of collector was the same and the pipes were staggered according to the firing order which meant extra 'bo-bo-bo-bo-bo-bobs' 😬 I'll have to find it.