Rover Testing

Rover Testing

We managed to test drive our rover eight days ahead of schedule this year. Our goal was to drive March 1st, instead we drove for the first time February 23rd. Although there were early tests in the rover construction process that involved testing certain areas of the rover, this drive date of February 23rd has really been our only drive test. However, we did learn a lot from the test.

This test provided important information on our drivetrain as well as problems with out initial steering design. Before we even got to driving the rover, our back left wheel had for some reason come loose. Later in the testing, our right wheel came loose as well. The reason for this is still unknown amongst the team; however, there have been some possible solutions put forth to prevent this from reoccurring. For instance, we inserted an additional shaft collar to the outsides of both wheels. This fix should solve this problem. Another pressing issue we learned of was our drivetrain. For one, single drive is probably not the best speed for us. Our front bike chain, which powers our back right wheel, came off of its sprocket on the transfer axle. This is clearly problem, and although a chain tensionor was already inserted, another solution will be needed, such as lifting the chain tensioner, or, if possible, shorten the bike chain. Another issue with our drivetrain was that the current speed is too slow. We will need a speed where the rover can pick up speed and our drivers won't have to pedal to exhaustion just for the rover to go a medium speed. Adjusting the gear ratios to where we get a good balance or speed and versatility will need to be done. Furthermore, the steering we had in place did not hold up during this test drive. The tie rod that is used to connect the two front wheels continued to fall off because the bolts connecting the steering hubs to the tie rod were too loose. Unfortunately, we need those bolts to be loose so the tie rod can pivot on those bolts, but that can't happen with the bolts falling out. moving forward, using a ball joint and having that connect to a rod might be a better option. The last adjustment we learned of was regarding our dowel rods, which keep our pedal arms locked in place. During testing, both makeshift rods fell out. So, we will need to order proper parts for the dowel rods (instead of parts just found in the Den) and place shaft collars on each ends of the rod, to keep them in place. Once these adjustment are made, along with the addition of brakes, we will go out and test drive this prototype. However, as we continue to work with this prototype, we will also begin construction on the final wooden rover and finalize our rover as our date with NASA approaches.