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mlusmore
02-09-2004, 04:08 AM
im doing a side project to go with my unis fs team - and just cant find any literature to work out the pitch centre. if anyone can point me in the right direction that would be great. cheers.
mlusmore
02-09-2004, 04:08 AM
im doing a side project to go with my unis fs team - and just cant find any literature to work out the pitch centre. if anyone can point me in the right direction that would be great. cheers.
Denny Trimble
02-09-2004, 08:59 AM
Think of it as roll center in the side view. It can be constructed using the same geometry (intersection of front and rear IC-to-contact-patch lines).

University of Washington Formula SAE ('98, '99, '03, '04)
Kevin Hayward
02-09-2004, 08:20 PM
You need to be careful when dealing with the term "pitch centre". Some may be referring to the pitch centre as the geometrical centre of the "anti" effects you may be running.

However there is a contrary definition that splits the front/rear modes of the car up into a pitch and bounce mode, each with their relative centre. This should be done with the FSAE vehicles as the dynamic index of pitch is much closer to about 0.7 than it is to 1. When it is 1 we have both a front and rear natural frequency independant of each other.

... Which is why I don't really like the data sheet that goes along with the design report. It asks for a front and rear natural frequency. What it should be asking for is a pitch and a bounce frequency.

Kev

Tyre destroyer
UWA Motorsport
Lukin
05-20-2005, 03:56 AM
Bit slow for the response...

What pitch frequency do you's get? I'm not involved with SAE anymore, but from FFord data we get a very distinct rise at 6.5Hz, which I think is the pitch frequency. Also, it is much more pronounced on the front axle, which I am at a loss to explain.

Cheers.
RagingGrandpa
05-25-2005, 11:53 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by mlusmore:
im doing a side project to go with my unis fs team - and just cant find any literature to work out the pitch centre. if anyone can point me in the right direction that would be great. cheers. </div></BLOCKQUOTE>From someone older and wiser-
"Pitch center? Shouldn't that be over home plate?"
heh