Badgerloop in California: Day 7
Date: Thursday, August 24 2017
Entering the day, we had only completed one of the major tests out of eight required and only had until Saturday to finish the rest. What followed was a defining day for our team as our success or failure today would largely determine whether or not our months of hard work were to pay off.
After a quick hotel breakfast, the pod was rolled back to SpaceX. Due to the electrical team’s hard work the night before, the pod was very close to being ready to perform tests as soon as we arrived.
The first test for us to pass was the functional test which requires us to successfully operate the electrical system as if a full run was being performed. To do this, all of the different phases of the run including pushing, propulsion, braking, and venting had to be demonstrated to show that we could control and receive data for each phase via our electrical system.

After many probing questions from the judges, the team was able to pass this test with flying colors! We were able to check off all the boxes necessary to move on and demonstrated that our electrical system was able to pass the first hurdle. The fact that we were able to pass this test immediately is a testament to the many hours of preparation our electrical team has put in, and it showed in their ability to successfully answer all of the questions SpaceX tossed our way. However, we weren’t going to be stopped there.
After completing the functional test, the team moved swiftly to prepare for the mechanical fit check. This test involves moving the pod onto an external track that SpaceX has set up on their lot, rolling it a short distance and actuating the brakes to ensure that nothing was interfering with the track’s I-beam. After a bit of anticipation in waiting to get access to the external track, the team was able to pass this test on the very first try! This was a huge win for Ben’s stability system and Arjun and Mitch’s braking setup, as it was proved that their systems allowed us to remain centered for the duration of the one mile run.

At this point, team morale was flying extremely high. The team was worn out from all of the unforeseen obstacles that had come up throughout the week but continued to persevere and fight through the adversity. This was also a landmark moment for us as a team, as we weren’t able to advance past the functional test at the previous competition. But we still weren’t done yet.
Shortly after completing the mechanical fit check, our advisors came over and told us that we could proceed to the next test right away if we chose to. Although we weren’t quite mentally prepared to begin that test, we were confident that we could pass based on how well we did in the previous two tests. After some deliberation, the team elected to take on the next test: the vacuum test. For this test, the pod is placed into a chamber which is then depressurized to remove all air from it. Upon depressurization, we must be able to show that our pod can successfully operate under the conditions of the tube and that we can still control everything from outside of the tube. Although we have a small vacuum chamber back in Madison that we can use to test individual segments of systems, we weren’t truly able to test any full systems in the pod prior to this test. Nerves were very high heading in, as a new group SpaceX engineers continued to ask us questions while we were performing this test. After a tense half hour or so, the team returned victorious having fully passed this test!

Once the three tests were finished, we were unbelievably excited. We truly did not expect to be able to go through all three of those tests today in such quick succession and we were ecstatic with our progress. However, the team was truly exhausted as passing those three tests required multiple hours of answering questions from SpaceX’s engineers and addressing any concerns they had. Despite this day of awesome progress, we still have a number of tests left to perform and won’t know our final standing until Saturday afternoon.
After meeting as a team and evaluating our chances if we were to move immediately onto the next tests, we decided to take a break and fully prepare for the tests to come. After working for another hour or two, the team moved the pod back to Bulletproof to spend the rest of the night preparing for what’s ahead.

In terms of remaining tests, we must still pass the state transition test*, the navigational test**, the external subtrack test*** and an open air run in the tube****. In order to achieve our mission of performing a full run in the tube on Sunday, we must successfully complete all of those tests within the next 48 hours.
After this productive day, it is safe to say that we are in the upper tier of all teams in terms of completed tests. We can’t go into to much detail but we are ready to keep progressing and will hopefully knock out all tests by the end of Saturday!

- * To pass the state diagram test we must present multiple pieces of documentation to SpaceX engineers and walk them through what will occur on our pod when we pass through the various states of the run (power on, beginning of propulsion, braking, power off, fault state, etc.).
- ** To tell our pods position in the tube, we attached three retroreflective sensors to the shell of our pod and monitor how quickly we pass reflective strips that are placed on the inside of the tube. For the navigational test, we must verify that we can do that outside of the tube by testing the sensors and ensuring that we can receive accurate data from them.
- *** The external subtrack involves running the pod on an I beam in the lot at SpaceX. For this test, the pod is pushed on the same short length of track used for the mechanical fit check. The braking and propulsion systems are pressurized well below full operating values as a proof of concept that they are functional
- **** The open air run is nearly the same as the final pod run on Sunday except the tube is not depressurized prior to running. In this test we would operate the pod as if it were a full run but since there’s still air in the tube, we wouldn’t go nearly as fast and would be able to ensure all systems properly function for the full mile long run.
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