Question about Percy, ergonomics and bell crank iterations

[Anvit Garg]

On www.formulastudent.com (http://www.formulastudent.com) there are a couple helpful documents regarding the new cockpit template as well as of the 95th percentile male.

http://www.formulastudent.com/universities/Rules.htm

Regarding the template, I do not see how they can "invert" the template once a low mounted steering column comes in the way.

As for Percy, there is an excel spreadsheed that has the dimensions, (I assume which include the helmet), but I can tell that it references a figure. At the bottom there is a citation "MJR 8-31-07"

Can someone please direct me to where I can find more info about that figure? Also if anyone has a suggestion for driver ergonomics, I am trying to figure out an ideal posture that lowers the driver's CG while still making the vehicle useable. (A book or website that discusses this?)

Lastly, I have been playing around with Autodesk Inventor, and for the bell crank design, I can not figure out a way to plot a table based off iterations for different bell crank configurations. I hear that Solidworks does this, is there an easy way to do it with Inventor? Should this be the approach for bell crank analysis, or do you guys typically derive a dependent set of formulas for a hypothetical bell crank set up?

If I do end up switching to Solidworks or Pro/E or CATIA, what function would be ideal for the iterations? (Solidworks - Design Table function, or something else?)

Thanks!

[A HOKIE]

Originally posted by Anvit Garg:

As for Percy, there is an excel spreadsheed that has the dimensions, (I assume which include the helmet), but I can tell that it references a figure. At the bottom there is a citation "MJR 8-31-07"

Can someone please direct me to where I can find more info about that figure?

In regards to Percy, I believe the figure you're looking for can be found on page 51 of the 2009 FSAE Rules.

FSAE Rules 2009 (http://students.sae.org/competitions/formulaseries/rules/)

[Anvit Garg]

You mean figure 2? That is just 3 circles with sticks.

I am having trouble designing because I need to know how long his legs are. I tried that figure and got the following:

http://img.photobucket.com/albums/v412/daconfusion/progress.jpg

I guessed on his knees and feet, by trying to use the 6' 3" mentioned on the official FSAE forums. But that was dated 2005.

If you see the numbers in the excel sheet, they resemble a figure like the one in this book:

http://books.google.com/books?...5&ct=result#PPA22,M1 (http://books.google.com/books?id=N3b-Eo6Vry8C&pg=PA20&lpg=PA20&dq=95th+percentile+male+shoe&source=bl&ots=LBySgInzR_&sig=3O8YvrmfKspipb3buSo_JgpxMao&hl=en&ei=Hwm_SbmdMpDMMLGi2K8N&sa=X&oi=book_result&resnum=5&ct=result#PPA22,M1)

Unfortunately, that book is even more dated.

[Tom W]

Percy doesn't have any legs, he is just three circles joined by sticks, the rules explanation of how the test is done is followed exactly at tech.

[Anvit Garg]

The reason why I am concerned with his legs are because I have to estimate where the pedals will be so that I know where the template will end.

That will help me figure out where I can place the dampers because I am trying for a pull rod set up.

[Michael Royce]

Anvit,
The dimensions you pulled off the Formula Student web site are the ones upon which we based Percy's dimensions. The dimensions are WITHOUT helmet. The 300 mm diameter circle in the FSAE Rules represents the head WITH helmet.

We used to have these dimensions on the official SAE web site too, but they seem to have been pulled off when it was redone.

[MalcolmG]

do you know anyone who is approximately the right height? I made a model of a human by taking the 95th percentile male's major dimensions and measuring myself for ratio of lengths of thigh to shin and upper arm to forearm. Worked pretty well

[Pete Marsh]

Don't try to use Percy for your ergo design, he is just ment to be a tech inspection tool to make sure your car is not too small. He doesn't sit in a race car the same as a real person, on account of being made of wood discs. People are softer and conform to the seat more. Why not measure your drivers and make it fit them? They are the ones that need to be comfortable in it.

[Anvit Garg]

That is a good point, I kind of forgot that the average person is not 225 lbf and 6'3" tall.

Thank you.