Ackermann Principle

[Admin]

Hmmm... I am now wondering about the value of this thread. I started it beacause I had read a few comments which indicated Toe Out On Turns was a misunderstood phenomenon. The motivation was partly selfish as I am undecided as to whether it is required in racing off road terms.

I had hoped to promote discussion to help enlighten us all.

I think I might have help cloud such enlightnement. My apologies to all if this is the case. I included the pic of the F1 car to highlight the use of Rev Ack because someone challenged its useage, not to endorse its use on our style of vehicle or to compare a 3" travel vehicle with a 20" travel vehicle.

Entropy you asked the question about credentials, I dont expect you to take my word on anything which I post, I expect you to investigate for yourself after being alerted to issues by my posts, as with all who use this forum.

Im a little agrieved that you should ask for credentials (we didnt ask for yours) but am going to supply mine, this once only.

Automotive mechanical engineer (all my life, im now 46)

Owned a suspension, steering and brake workshop for most of my early life

Taught braking suspension steering practise and theory at university for 10 yrs to training engineers

Last 10 yrs as a financial investment adviser (Which has only taught me the folly of owning these cars..but who cars)

My racing history is by way of speedway sports sedans, go carting, formula 3000 (aussies version), off road (full sized) and now superlites (aussie class) Ive never been any good at any of these but have immensley enjoyed myself.

I am not now and never have been a Duner, so I do not understand the needs of this class of vehicle use, nor do I use the vehicle in any recreational way, apart from testing all my wheel time is under racing conditions.

Entropy, all posts on this site are opinions, if you wish to dismiss opinions, please do so, but please don tell us you are dismissing our point of view. Thats somewhat personal. And mate, I dont talk out my arse.

No need for apology's on this forum, were about ideas etc, It is nice to know when someone has credentials and not speculation, I understand entropys suggestion of that... Keep up posting artie, this is what makes a forum, No ones calling names yet so were good to go...

[artie on edge]

Hi Bug, and there will never be any name calling (at least on my part)... does any one remember my very first post?

Big hugs...I loves yus all........ peace bro...suck suck suck..... aaaaahhhhhh thats good shit man.......
 

[Entropy]

Hmmm... I am now wondering about the value of this thread. I started it beacause I had read a few comments which indicated Toe Out On Turns was a misunderstood phenomenon. The motivation was partly selfish as I am undecided as to whether it is required in racing off road terms.

I had hoped to promote discussion to help enlighten us all.

I think I might have help cloud such enlightnement. My apologies to all if this is the case. I included the pic of the F1 car to highlight the use of Rev Ack because someone challenged its useage, not to endorse its use on our style of vehicle or to compare a 3" travel vehicle with a 20" travel vehicle.

Entropy you asked the question about credentials, I dont expect you to take my word on anything which I post, I expect you to investigate for yourself after being alerted to issues by my posts, as with all who use this forum.

Im a little agrieved that you should ask for credentials (we didnt ask for yours) but am going to supply mine, this once only.

Automotive mechanical engineer (all my life, im now 46)

Owned a suspension, steering and brake workshop for most of my early life

Taught braking suspension steering practise and theory at university for 10 yrs to training engineers

Last 10 yrs as a financial investment adviser (Which has only taught me the folly of owning these cars..but who cars)

My racing history is by way of speedway sports sedans, go carting, formula 3000 (aussies version), off road (full sized) and now superlites (aussie class) Ive never been any good at any of these but have immensley enjoyed myself.

I am not now and never have been a Duner, so I do not understand the needs of this class of vehicle use, nor do I use the vehicle in any recreational way, apart from testing all my wheel time is under racing conditions.

Entropy, all posts on this site are opinions, if you wish to dismiss opinions, please do so, but please don tell us you are dismissing our point of view. Thats somewhat personal. And mate, I dont talk out my arse.

Artie.
Please take no offense at my statements they are in no way intended as personal attacks to you specifically, or anyone.

Like you I have been around a while, high speed Desert type dirt for 20 years spent a few years doing the SCCA road race thing (Novice to GTU) and a few other high speed pursuits on water and airborne; and read all the books and have no degree in it but I have been pressed into teaching it twice.

99% of the time on the web I seem to run into 12-yearolds at their mommies keyboard spouting some antiquated shit their grand daddy tried to teach em, and they have wrong.
When faced with a question I find it simply best to man up and ask the question, even if I ruffle a few feathers...

So let me be clear, there ain't nothing personal about anything on my end, and if I ticked you off I apologize as it was not my intent!



Masterfab you getting a picture yet?   Sorry inside joke.

[artie on edge]

Mate, no issues personally (please see prev post "as I preen my disturbed feathers....Im all unruffled again") and its always good to use the "thor" system (Transparency, Honesty, Openness, Respect) its what I like about this particular site. I apologise for bristling up in the first place...

Cheers...me happy.

[karman1970]

My agruement FOR Ackerman stems from the following: the majority of my racing experience, aside from hanging around the pits at vintage races, has been with the Baja SAE program.  For those who don't know, our cars weigh about 400-500 pounds dry with a 10 horse Briggs limited to 3800 rpm.  They top out around 40 mph.  Since our speeds are relatively slow and we can't peform "throttle induced oversteer,"  proper steering geometry is a must.  The difference between pushing a Baja car with 100% pro-Ackerman and anything else is tremendous.

I often refer to asphalt cars for suspension discussions because that's what I have a better understanding of (I didn't get involved with off-road racing until about 5 yrars ago).  Besides, in theory, how much different is an off-road suspension from an on-road one?

[Entropy]

SNIP<Besides, in theory, how much different is an off-road suspension from an on-road one?

Not much really, sort of like morning and evening the sun is still up just on the opposite side of the planet...

[SPEC]

I know the inside joke
I have been following this thread from the start It is a good thread...
It has people thinking and doing some research whether it is in they're memories,past experiences, or looking it up now...Here's my take on it...
I use ackerman on my builds, why? way back before the internet, All I had to go by was the knowledge that had been handed down to me by the dirt track oval guys...The winners/track champions...often took that little kid into their pits and let them watch...After a crash at the state fairgrounds I think in 1976, I was standing in Dick Trickles pit and noticed that with the front tires turned to almost full lock that the inside tire was turned noticeably further than the out side one...I ran up to Dick and told him his car was effed up...He kinda giggled and told me that helped the car to turn better...That was all I needed...
Whether It be sand,dirt, asphault or your Nabe...I think that a little ackerman can't hurt...Here's a tidbit from the spec archive...When powersliding carrying the inside front it IS unpredictable when that tire will touch ground again...I want it pointed in the right direction when it does

[fabr]

Artie.
Please take no offense at my statements they are in no way intended as personal attacks to you specifically, or anyone.

Like you I have been around a while, high speed Desert type dirt for 20 years spent a few years doing the SCCA road race thing (Novice to GTU) and a few other high speed pursuits on water and airborne; and read all the books and have no degree in it but I have been pressed into teaching it twice.

99% of the time on the web I seem to run into 12-yearolds at their mommies keyboard spouting some antiquated shit their grand daddy tried to teach em, and they have wrong.
When faced with a question I find it simply best to man up and ask the question, even if I ruffle a few feathers...

So let me be clear, there ain't nothing personal about anything on my end, and if I ticked you off I apologize as it was not my intent!



Masterfab you getting a picture yet?   Sorry inside joke.
Yup Clear as muddy water.

[artie on edge]

My agruement FOR Ackerman stems from the following: the majority of my racing experience, aside from hanging around the pits at vintage races, has been with the Baja SAE program.  For those who don't know, our cars weigh about 400-500 pounds dry with a 10 horse Briggs limited to 3800 rpm.  They top out around 40 mph.  Since our speeds are relatively slow and we can't peform "throttle induced oversteer,"  proper steering geometry is a must.  The difference between pushing a Baja car with 100% pro-Ackerman and anything else is tremendous.

Karman, Im totally unfamiliar with this class of car, any chance of a few pics of your beasty with more inf on its make up?

[Admin]

Its the college program....

http://students.sae.org/competitions/bajasae/

[fabr]

Not much really, sort of like morning and evening the sun is still up just on the opposite side of the planet...

I think he means different as night and day.  There is actually quite a bit of difference.

[artie on edge]

[fabr]

WOW! guys! I leave for 2 days and a great debate breaks out. I LOVE IT!!!!! This is what gets the info out so we can make our own decisions from an educated standpoint.I'm not saying we'll make the right decision but without info I'll guarantee you it'll likely be the wrong one.

[Entropy]

I think he means different as night and day.  There is actually quite a bit of difference.

Ya know I was wondering about that myselph. :-[

[karman1970]

I think he means different as night and day.  There is actually quite a bit of difference.

But the whole purpose of the suspension system is to keep all four wheels planted on the ground when traveling over uneven terrain or cornering.  Dirt track and asphalt cars don't see the same range of movement as buggies or rock crawlers, but the principle still remains, right?

Here's our team website: web.mst.edu/~baja