Vsusp has been a huge help in sorting out my suspension tradeoffs. It has literally saved me hours of work. It’s proved a little addictive though, so not all the savings are net.
Thanks, Rob, for putting Vsusp together and continuing to add improvements.
Here are a couple of add-on tools that helped me with my VSUSP efforts. They do pre-processing for specific knuckle/spindle configurations. Some of the calculations, like control arm length, may eventually find their way into Vsusp. Others that are more hardware specific are less likely to.
In exploring rear suspension alternatives using T-Bird knuckles on Vsusp, I was playing with a number of design elements (tire size, ride height, pivot points, etc.) This in turn was causing a lot of hand calculation to create Vsusp inputs (Xs, Ys, and control arm lengths.) As my T-Bird knuckle dimensions were known and fixed, a little spreadsheet app was created to do the work. I can now feed the spreadsheet my parameters (page 1) and have it calculate and/or copy them into Vsusp inputs (page 2). This saved me a lot of time playing with the many possible variables. The spreadsheet (Vsusp Input Generator) in the attached zipped file includes measurements of my T-Bird knuckles. Your dimensions might vary, but these should be close for most T-Bird knuckles. I haven’t tested it, but with a different set of fixed knuckle dimensions, the spreadsheet might also work for Miata or other rear uprights.
Attachment:
VSUSP Input Generator for T-Bird Knuckles - V2.0.zip
Similar problem with my front suspension; I was trading off a large number of variables. Some months ago I posted a spreadsheet which takes the Wilwood Mustang II dimensions and geometry (from Wilwood’s engineering drawings), along with (for Car9 at least) a set of chassis design inputs (page 1) and creates the X,Y,Z inputs needed for Wishbone’s 3D suspension calcs (page 2.) But as Vsusp’s graphical user interface is so much easier to use, a third page has been added which maps the Wishbone 3D inputs into Vsusp 2D inputs. (Note: Vsusp's X’s and Y’s are defined differently from Wishbone’s X,Y,Z’s which can cause confusion.) The updated Wishbone Input Generator spreadsheet is also attached below. This spreadsheet has allowed me to rapidly make multiple Vsusp runs while exploring a number of front suspension parameters including monoball pin lengths, ball joint stud lengths, etc. without a lot of foreplay required
Attachment:
Wishbone Input Generator V4.0.zip
So, I’m not done with the suspension work yet. Still fine tuning my RC heights, camber correction curves and Roll Axis inclination with Horizonjob. But here's the current Vsusp Project Link for the front and rear as defined in the two spreadsheets:
Car9_Tom1And here are the current roll charts:
Attachment:
front roll chart 2013-12-15.jpg
Attachment:
rear roll chart 2013-12-15.jpg
Advice, comments and suggestions are always appreciated. Hope some of this is useful to other Locosters.