The vehicle performed well during the first test which was to determine if the suspension system could support the vehicle. The calculated impulse from the vehicle dropping 24” in was an approximately 8lbf (10.84 J).Though the test did not determine the actual impulse it did determine that during that impulse the suspension system is functional enough to avoid bottoming out during that drop height and to support the vehicle during normal use.

The second test was the 1.5” static obstacle. This was considered the minimum obstacle size that the vehicle would have to drive over. We determined the overall travel for the front suspension to be 1.67” of travel. Which was greater than the estimated value of 1.5”, however it passed this test so easily we then upped the differential to 2” which it also passed.

The third test was to determine straightness of driving and predictability of steering. It was estimated that the sprint course for the competition would be approximately 20ft long, so that was the target distance for a straight away drive length, and the target was to have a less than six inches of deviation during that 20 ft. Unfortunately the test was a failure. After visually inspecting the final design I determined that the source of the failure is in the fitment of the steering components. Originally the components would have fit perfectly, but the original components could not be used due to errors in manufacturing. The store bought components that we ended up using were larger and did not fit as well. This resulted in a loose steering system and the failure in this particular test.

The fourth test I believe was also effected by the store bought components. The right side of the store bought steering knuckle fit better than the left, because the left side was stripped out during a speedy installation at the competition. Not coincidentally that side also failed the steering radius test.

Conclusion:

Though the vehicle did not pass all of its test during this testing gauntlet, I feel it has performed well considering that it did perform greater than 75% of the other vehicles at the competition. The vehicle also went through this testing gauntlet after it has been broken and repaired numerous times. In the end I feel that a lot of the errors that occurred during this process could have been avoided if I had not tried to use the 3-D printer for my primary method of manufacture. I really wanted to utilize this new way of manufacturing, however I should have been more focused on the end product and machined more parts from steel or aluminum. Though this was a great learning experience, and I am happy and proud of our vehicle if I could do the whole thing over again I would make different manufacturing decisions.