Many years ago, the Alan Clarinval Supersport 22 racecar had a hydraulic suspension, which, for then unknown problems, caused the race team grief. The team switched to a standard mechanical suspension after some time, with a bit of modification to the car. CSU acquired this car, along with the original hydraulic suspension parts. Unfortunately, the only evidence of how the hydraulic suspension was mounted are the holes drilled in the front plates and two very grainy pictures of the front hydraulic suspension mounted on the car.
With fellow REU student Mike Senger working on reconstructing the hydraulic suspension, Dr. Fitzhorn assigned me to construct the front and rear suspensions in the computer program ADAMS 2003, using the regular mechanical suspension first, then changing the model to implement the hydraulic suspension. Estimating masses and inertias, I was to get a working suspension setup constructed, able to produce accurate test results.
Before the suspension could be modeled in ADAMS 2003, I needed to acquire the measurements of the car as accurately as possible, so as to simulate the car as realistically as possible. Using string, two straightedges, and a few rulers, Mike Senger, Ethan Coffey and I took measurements of all the major points of the car’s suspension. After all of the measurements were taken, I put the measurements into ADAMS 2003 and began constructing the suspension.
both the front and rear, I modeled the suspensions in multiple phases.
Because the suspension of the racecar is rather complicated, I started
with a very simplified version of the each suspension. I took joints
that were close together and made them join at the same place. Both
front and rear suspensions have a device called an anti-roll, a flexible
blade that, when one wheel is pushed up, the other is pushed up as well,
so as to prevent the car from rolling.
After modeling both the front and rear suspensions in
ADAMS 2003, I was able to look at a variety of tests. For the simplified
model of the rear, a right single wheel travel produced the same results
as a left single wheel travel. When I made the model more complex, namely
connecting the anti roll links in a Y shape rather than a direct connection,
different results were produced from a left single wheel travel versus
a right single wheel travel. A graph of this can be seen in the “Rear
Suspension” section. Also, as I started switching the connection
points to the more complex model, the results changed slightly, but
not in any great fashion as with the anti roll links.
For pictures of these results, please see the tables below for the corresponding suspension setup. Click on any picture for a larger version.
Special thanks and acknowledgements to the ARO, NSF, and CSU. Thanks to mentors Paul Heyliger, Patrick Fitzhorn, and Don Radford. More thanks go to Ethan Coffey and Mike Senger for their help.
If you would like to download any of my files, please see below. Please credit me if you wish to use these anywhere. Some files may not work properly first time out. Please work with it to get some proper results.
Front Suspension (.zip, includes hydraulic)
Rear Suspension (.zip)
Body (.zip with .x_t file)
Wheel (.zip with .x_t file)
Email me at the following addresses with questions, comments, or concerns.