Tai Le
Intro To Digital Technology
May 26, 2008
Catapult Reflection
What was the challenge?
Our challenge for this project was to be able to build a catapult made from PVC pipes, and would initially work as a real catapult would. The catapult would have to be able to go through obstacles that our teacher had planned out. The requirements for the building of the catapults in general were that it had to have no more the 14 inches maximum in length, 8 inches maximum in width, and 18 inches maximum in height. Our materials that we had to use to build our catapult included 10 inches or PVC pipes, 4 Tees, 6 elbows (PVC pipes), 1 Slip Tee. All of the materials that we were given we made from PVC pipes, or as many people would say, plastic. When my teacher announced that we would have to build a catapult and have it go through obstacles, I felt very excited. In my mind I was thinking, “Hey! This shouldn’t be that hard. I mean, I had to build a catapult out of wood in 7th grade! No biggy”. Little did I know what challenges laid ahead for me.
What was your design?
When we designed that catapult, I contributed to the layout of the catapult when we had to hand them in to our teacher. My partner contributed the “spunkyness” to the group, and she helped pitch in when we were cutting the PVC pipes. Although her fear of knives and PVC cutters was an obstacle, I’m glad she was there to help out. The main layout of our catapult was that it’s width, and length were exactly 8 inches wide, and 14 inches long. Our base used 4 Tees to hold together the “catapult stop” and the PVC section that held onto the catapult. Our arm was about 16 inches in total length when attached with or catapult. We had drilled two holes in the PVC pipe to place our two thick, and two skinny rubber bands in the holes for more resistance when the arm was pulled back. Well for the catapult to “shoot”, I would have to pull the arm back, and my partner would step on the catapult so the catapult wouldn’t bend back by the force on the arm. Initially we didn’t plan for a stopper to stop the arm when it was pulled back, so my partner and I had to go back, and change our layout of the catapult, in order to stop the catapult arm. We made a stopper about 6 by 6 inches was placed 2.5 inches from the catapult arm so when the arm was pulled back, the stopper would stop the arm from going any further. We found that without the arm, our catapult would shoot straight into the ground, and not go any distance at all.
How was the construction phase?
On my team, my partner and I both contributed in cutting the PVC pipes whether it’s holding the pipe in place, or even cutting the pipes. When the parts were all cut, we decided that I would assemble that parts, and my partner would watch me assemble and note if I had any deficiency in my assembling. Problems that we encountered? Never trust your drawing layout to be exactly the length, width, and height it promised. When we completed building our catapult, it was too long, so we had to shorten a few more parts. Not only was our paper lying to us, but we forgot to place a stopper in our catapult to stop the arm from going any further. Like I said earlier, our catapult matched our drawing about 80% of the time. I thought I would have been deducted points for changing anything on the catapult, so I drew out another layout of the catapult, and showed or teacher. We really had to changed part of our catapult because like I said earlier, it was missing a stopper, and if we did not have that crucial part, our catapult’s arm would be throwing objects straight into the ground. Our scale drawing was very useful because we referred back to it many times when about to cut our PVC pipes. We needed the drawing to know how many pieces or PVC pipes we were to cut, or what the length in cutting that PVC pipe was. Changes to our catapult included adding a stopper, and reducing down the catapult to fit the requirements.