Argonia Cup 2017

This past weekend was the first competition for the Oklahoma State University AIAA High-Power Rocketry Team! We competed against the Mississippi State University Space Cowboys and the Saint Louis University Rocket Propulsion Laboratory in the inaugural Argonia Cup, hosted by Kloudbusters in Argonia, KS.

The objective of the Argonia Cup 2017 was to take a golf ball payload to 8000 feet and recover the payload as close to the launch site as possible using a single L motor or less. Upon registration in November, our team dived into the project of the payload recovery system in January. I asked Nick Foster to head the program based upon his experience and research with drones and UAVs. Over the next three months, he and his team along with financial and logistical help from Dr. Jamey Jacob and the Unmanned Systems Research Institute (USRI), they developed an autonomous spring-loaded drone to fit inside a 4” diameter rocket. Using GPS and several other sensors and instruments, the drone would release itself from the rocket during the main recovery deployment event, begin flight, and pilot itself to the launch site. Most parts were 3D printed and all was made right here at the university.

 

Meanwhile, our rocket design and assembly teams worked on the ascent vehicle to take the UAV to 8000 feet. We faced a sizable constraint in that due to our financial situation, we were unable to purchase the necessary reloadable motor hardware for most L motors (75mm hardware). Additionally, there were no 75mm reloads even available for purchase. Therefore, we had to fly on the most powerful 54mm motor available, a single-use L1000W. It would be questionable if we’d even surpass 8000 feet, as simulations indicated the final rocket weighing at 17.3 pounds would barely reach that altitude. We proceeded nonetheless because simulations can frequently prove inaccurate, and we had no other feasible options.

To maintain the tradition of naming our rockets after professor quotes, this rocket, It Depends, was named after our applied aerodynamics professor, Dr. Jacob. Why “It Depends?” Because it is the answer to many of the questions he asks in class regarding designing aircraft. “Should this aircraft have winglets? Well, it depends.” He is the director of USRI and thanks to his help and financial support, we purchased two motors for the competition in case we had the chance to fly a second time.

We had most of the rocket completed in late March as the Argonia Cup was originally scheduled for April 1^st and 2^nd. Due to weather, it was postponed until April 8^th and 9^th which gave our team an extra week to prepare.

However, no matter how much planning and work gets done ahead of time, the final preparations will always be made 6 hours before departing for a launch. We spent Friday evening of the 7^th making these final preparations and left the lab at 2:00 AM. I got all of an hour and a half of sleep before waking up again to return to the lab. We had a good group going with us including half of our team who would stay Saturday evening to camp on the rocket pasture to see some more launches Sunday morning. This worked out very well for us.

At 6:45 Saturday morning we loaded up the vehicles and were on the road at 7. I rode with my former roommate and just before the Kansas border, a wheel gave out, so we pulled over to have a look. He has done plenty of work on his truck and recognized the problem to be a blown wheel bearing. We called a friend of ours also heading to the launch, and he provided us rides into Blackwell just a few minutes away to purchase replacement parts and tools for the fix. After propping a jack upon several cinderblocks, we removed the tire, brakes, and broken wheel bearing. The cylindrical bearings had been smashed to bits. Unfortunately, upon replacing it with a new bearing, the bolt threads stripped, so they made a second trip into town to buy new bolts. Once they returned, we tried with the new bolts, but the stripped bolts also stripped the threads of the brand-new wheel bearing. They made a trip to Ponca City and an hour later returned with another $150 bearing. This time everything worked, and five hours after pulling over, we were back on the road. Even better, his truck now runs better than it has in a long time, so that was a plus.

When not flying rockets, we can work on cars, too.

Nic representing us with our t-shirts by the side of the road

We arrived at the rocket pasture mid-afternoon and got a status update from the rest of our team who arrived first thing in the morning. We had one successful Level 1 certification flight and one unsuccessful one. For the latter, the fiberglass V2 kit didn’t have a recovery deployment event, so it lawn-darted from a thousand feet and the two-foot tall rocket buried itself nose-first up to its fins in the soil. The whole thing splintered into a dozen pieces, and the remains couldn’t be more spectacular. It is always impressive how much energy there is in such a system when the recovery system doesn’t succeed.

As for our Argonia Cup entry, the drone wasn’t where we wanted it, so Nick returned to Stillwater for the evening to work on it more. With two hours remaining in the day, we prepared our Spaceport America Cup test rocket. It was the first rocket we launched in October, It’s Trivial, with an additional middle section containing our airbrake. For this flight, an external switch initiated the mechanism on the launchpad that oscillated moving fins to induce drag mid-flight. The final product will be a PID-controlled design that will compute apogee and induce drag in real-time. Anyway, this launch performed beautifully with the oscillating fins operating throughout the entire flight. We know this because we had an on-board video recording the whole thing.

Part of our Spaceport America Cup Team

That successful test launch was a good way to cap off the first day. As for our competition, both other teams launched their entries Saturday. Mississippi State flew some 15000 feet and landed more than two miles from the launch pad. Saint Louis flew more than 10000 feet and landed a mile and a half from the site. Neither team had anywhere near the sophistication of our autonomous UAV; theirs were little more than a parachute tied to a golf ball. This statement is amusing after what happened to us the next day.

Half of our team returned to Stillwater Saturday. The rest of us set up camp and drove to Wichita for dinner. Fizz Burgers was delicious, and it felt refreshing to make a run into the city. When we returned to the rocket pasture at 9:00, the Kloudbusters were sitting around a gas campfire, and after I said hello, they said our team should join them around the fire. It was a blast listening to their stories of the dumb things they’ve done and others (especially college students) have done over the years. I’d say we’re in good standing with them.

Team photo Saturday afternoon

After the short night previously, it was a real treat to sleep a full eight hours outdoors. A member of our team made us pancakes and bacon for breakfast, and we got the rocket ready during that time as well, anticipating a mid-morning launch and returning home by early afternoon. This did not happen.

Sunrise

The drone was fine, but our altimeter arming switch broke, so we had to solder a new one and affix it to the sled. Once that was complete, we learned that our two tracking systems operate at the same frequency as the drone, and Nick was afraid interference from the trackers would cause the drone to malfunction. This meant we had to ditch both trackers and fly the rocket blind into dense, low-level cloud cover. We would however get a GPS reading from the drone throughout, but the drone and rocket would separate on descent, so not even that was completely reliable. We sent out two extra tracking teams at various places down the road and with radios, we could communicate with those at the launch site.

It Depends, weighing 19.5 pounds at the pad, took off the pad just after 1:00 in the afternoon, disappearing into the clouds in seconds. Without tracking, we’d have to hear the GPS readout and hope we could see it as it reentered below the clouds. My friend happened to see parts of a rocket land with a thud in the wheat field in front of us. Those at the launch site confirmed that was in fact our rocket, and what remained of it was lying in that field. 

We headed in and discovered our very muddy and partially damaged rocket. The aft airframe was filled with six inches of wet soil and stuck upright out of the ground. The sixteen-inch nosecone was buried to its base level with the ground. The drone was smashed to bits. It took a while to figure out what went wrong: the main ejection charge never fired (altimeter lost power), hence the main chute and drone never deployed causing the connected halves of the rocket to tumble down from 8000 feet. The splintering of the nosecone and drone occurring upon impact with the ground rather than an issue during flight. We found out also that even if everything had gone smoothly, we wouldn’t have had a qualifying flight because the whole rocket flew just shy of 8000 feet.

Drone remains

As we’re analyzing the wreckage, my friend pointed out that the only component of the rocket truly damaged was the nosecone. We had another nose from It’s Trivial, the rocket we flew yesterday. Upon the realization that we could clean mud from the rocket and reconfigure the recovery system, we could fly a second time using the extra motor we purchased. The catch was we had two hours to do so before the competition ended.

What ensued next was a blur because we did so much in those two hours. We ditched the drone payload to save weight, and reset the altimeter to prepare for this flight. We used the plastic nosecone from It’s Trivial, but because there wasn’t a secure point of attachment, we were uncomfortable affixing the main parachute to that nosecone. Nick came up with a clever idea to use the Jolly Logic Chute Release altimeter to deploy the main rather than by black powder. This nifty gadget uses a rubber band and pin to wrap around a parachute and then at a certain altitude the pin releases allowing the parachute to unfurl. This would allow us to put the drogue-ejected shock cord (to be deployed at apogee) in the same rocket section as the main parachute, all aft of the altimeter bay.

One problem with this Jolly Logic altimeter (or Jolly Rancher as the Kloudbusters call it) is that we’d never tested it and couldn’t guarantee it would work (especially after taking the hard hit with the ground earlier that afternoon). While we’re preparing It Depends for flight, we had a team prepare our small rocket, Dynamic System, for flight to test the Jolly Logic. So, we flew another rocket to test the component we’d put in our competition entry, all over the course of a half hour. As Dynamic System took off, it separated properly, but the main didn’t deploy. Turns out the chute release worked, the parachute just got tangled.

That was all we needed, and we could make the final adjustments for It Depends. We got the rocket out on the pad, and this time we had trackers installed, so we weren’t worried about losing sight of it this time. I went out with the tracking team, and just thirty minutes before the launch window closed for the competition, It Depends roared off into the breezy, blue Kansas sky.

Standing in my friend’s truck bed, we kept our eyes peeled for the rocket halves and after some time, I happen to look behind us and see it tumbling just a short way away and at 600 feet, the main unfurled, gently dropping our rocket into a field. We were ecstatic because we knew we’d gone over 8000 feet and were far closer the launch site than any other team.

We recovered the rocket to hear the altimeter beeping out 8744 feet. Kloudbusters verified our location to be 0.7 miles away; next closest was SLU at 1.5 miles away. With that, we had won the Argonia Cup, and we returned to the rest of our team blaring “Eye of the Tiger” as we pulled up.

We took photos with the Argonia Cup trophy and were presented our winnings: $500 cash and an Altus Metrum TeleMega $400 altimeter. Bob Brown, the Kloudbusters club prefect, told me congratulations, and he was glad he didn’t have money on this because he didn’t think we’d be able to pull off a second flight, let alone one that was successful and won the competition.

 

With that, we packed up and left the rocket pasture at 18:00. At this point, exhaustion hit us. None of us had eaten anything since breakfast, and the sun got intense through the afternoon. When we originally planned this weekend, we expected to launch all our rockets Saturday, camp that evening, and return home Sunday morning. Not what we expected for the weekend, but I don’t think you’d find anyone who was discontent with our results.

We returned to Stillwater around 9:00 after a celebratory dinner at Taco Bell. We were all thrilled with the competition, but it was nonetheless a very long weekend. It didn’t help that I had three assignments due the next day, and I didn’t get to bed until 3:00 that morning.

On Monday, I got to talk about the competition briefly in front our Applied Aero class (Dr. Jacob is the professor) and show a few videos. Our team has received congratulatory remarks from our friends and the Mechanical and Aerospace Engineering department head.

Through all of this, I’m still trying to comprehend that this rocketry program didn’t even exist eight months ago. Even six months ago, we had no other certified rocketeers, hadn’t flow a rocket with electronics, and hadn’t gone above 1000 feet. Now, we are sponsored by NASA, have the attention of the whole college, and won our first-ever competition. I haven’t done this all on my own by any means, but I do feel that I’ve done a couple things right to get this team where it is. I can’t wait for what else we’ll accomplish together. My only “regret” is that I wish this idea had come to me my freshman year. I’m thirteen months away from graduating OSU, but there is so much more I want for this program. At the very least, I hope I’ve given it the foundation it needs to grow for many years to come.

Inaugural Argonia Cup Champions 2017