Mechanical Engineering Department
BS in Mechanical Engineering
John G. Fabijanic
The Suspension Solutions design team has completely designed built and tested an independent rear suspension system for the 2008 FSAE car. The car currently features a solid rear axle, and the task of converting it to incorporate an interchangeable rear suspension has been undertaken in order to quantify the advantages and disadvantages of each design philosophy. The car has been properly tested with both the solid axle and independent rear suspension side-by-side, however more testing is suggested. After pushing both setups to their limits on a 50ft diameter skid pad, the test results were quantified, and a final comparison between the two design philosophies was tabulated. From our limited testing we can easily conclude that an IRS FSAE car, at minimum, can match the performance of the previous solid axle setup, while being 22lbs heavier. We suspect its performance advantage to become apparent with additional testing however. More subjectively, it was found that the IRS handled more predictably and was easier for novice drivers to control and drive. Our results help quantify the advantages and disadvantages of each system and can be used by future FSAE teams to make more informed design decisions. Our independent rear suspension design includes an unequal length A-Arm configuration, new rear uprights, spindles and hubs, a Torsen differential, and an additional steel space frame to connect all of the listed components to the CP08 chassis. Our initial analysis shows that a performance edge between the two competing systems is dependent on the overall weight of each system and our preliminary testing results help confirm this analysis.