Imagine RIT a Huge Success
Posted May 07, 2010 by Matt | Tags: launches
Imagine RIT was a giant success for Team Urban Siege! We brought both the Melon Felon and Janus to demonstrate to the thousands of people coming to this event to see what students are up to at RIT. In fact, the official total was 32,000 people for this one-day event, and we saw many hundreds, probably well over a thousand, at our location alone, which was well away from the other exhibits (for reasons that should be obvious). All three members of Team Urban Siege are attending RIT currently, and while in past years we discussed doing it without really pursuing it, this year we went for it, especially since two of us graduate in two weeks.
Unfortunately, Janus had problems right out of the gate. First off, the one-pound iceballs that we made were putting enough stress on the release pin that the pin was bending with every shot, resulting in several shots straight up, one almost hitting a nearby exhibitor (still sorry about that!) Some quick work in a campus machine shop found some pieces of 1/4-inch steel that were modified into a new pin. Unfortunately the first one was too long and we forgot to check the clearance with the base. On the first shot, the pin smacked into a crossbrace, bending several components of the release pin. Repairs were made and a new, shorter pin made, which held up beautifully. Thanks again to Matt's dad for running errands and doing some shop work for us.
We took several shots, with some fantastic shots that wowed the crowd with their intense speed (we later calculated speeds in excess of 110 miles per hour, with only 100 pounds of counterweight!) Ranges were in excess of 600 feet in several cases (trees began around 550 feet). We were slowly bringing the trajectory back into optimal. Then the arm caught the trigger line during a shot, breaking a pulley we used for cocking and triggering. In fact, the pulley wheel simply disappeared, with a few small chunks left behind. While we could have worked around this without too much difficulty, and were we firing on our own we would have, the fix would have been jury-rigged and a bit unsafe for all the people to be around. Thus we had to take Janus off-line in the early afternoon.
The good news was the Melon Felon was operating just fine throughout this time. We had started off the day launching the 4-pound medicine ball with it, attaining between 150-175 foot distances pretty consistently. After Janus was taken off-line, we made the decision to switch pouches and shoot the iceballs from Melon Felon. Since Melon Felon carries a 300 pound counterweight, this was a mass ratio approaching 300:1, eceptionally high for a standard hinged counterweight trebuchet, but Melon Felon is so overbuilt that we were not worried about potential damage. And it took to throwing these iceballs immediately. With only a little tweaking of sling length and release pin angle, we were chucking the iceballs between 400-500 feet, which the crowd absolutely loved. We also started letting the many young kids that were present with their parents pull the trigger. We soon had a line for pretty much the entire afternoon of various kids wanting to fire the trebuchet. And every one of them seemed to love it.
We also brought a 1-foot axle height hinged counterweight trebuchet that Matt made for an experiment class in the fall. With 15 ounces of lead as a counterweight, this little machine fires small rubber balls (like those you get from vending machines) roughly 20-30 feet. The best part was that the kids loved playing with it and figuring out how it works. Several parents inquired about plans for this machine, especially as a cub scout project, and so we will be working to make a set of plans and instructions for just such a machine early this summer. It is a great instructional machine for young kids, relatively safe (aside from potential eye-poking), and easy to make. Stay tuned for the plans, we will announce when they are ready to download.
We will also be getting a gallery for Janus up shortly so that everyone can see this beautiful new machine we have built, it really looks great and for the most part has operated well too. We have to rework the cocking and triggering mechanisms, but the actual machine fires extremely well, and might well break the 1000-foot barrier with 1-2 pound projectiles! 800 feet is certainly looking likely at the very least. Stay tuned for these updates as well.
