Compound Machine Project

Compound Machine Project McGarrah Period 4 - Honors Principles of Engineering September 23, 2022 - October 14, 2022

In this project, I worked with my tablemates, David Loo, Joseph Ficarra, and Frank Xiao (as seen on Top image on the left). The objective of this project was to design a compound machine that used at least 4 of the simple machines that we learned in class. We needed to make sure that the compound machine must be triggered by a single human input action and must fit within a single base plate provided by our teacher. After brainstorming and reviewing several ideas on what function the machine will perform, we decided on the “Press Enter Key” idea which had the highest total score in our Decision Matrix. Each of us then had to come up with 2 ideas for what the potential machine could be made of using multi-views and isometrics (with labels, dates, and descriptions of each minute detail in the sketch) to give our ideas a visual. We ended up going with my first sketch idea (middle image on the left) because it was the most efficient and easiest to build including all 4 simple machines. David then made an isometric sketch of my design sketch so that we would have a better 3D view of what we might want our project to look like. We then began to work on building each machine one by one. First, we build the chain and sprocket since they were the ones with the most height that was the backbone of our compound machine. Then we built the Wheel and Axle system that and attached it to one of the sprockets from the Chain and Sprocket system. This wheel will rotate left via the input force and the axle will spin the rest of the components through the sprocket chain system. We then added our Incline Plane and First Class Lever below the Chain and Sprocket system so that we could add the weight to a string that would be attached to the chain to drag the mass up an inclined plane whenever the Axle spun. The weight would then fall onto one half of the First Class Lever. Our first class lever, will be pressed by the weight and the side with the string will move up. That string is connected to the first class lever and taped down for consistency. After we built the First Class Lever, we needed to add another simple machine to the other end of the First Class Lever which was the pulley so that when the first class lever is activated, the string will be pulled up. This will give the mass hanging from the other side leeway to strike down on the Enter key. The weight was a tiny weight 5 pound weight which was just heavy enough so that it can hit the Enter key of a keyboard. Once we did a few trial runs to make sure that the Enter key is pressed every single time, we were able to record a video of our project in motion. The overall Ideal Mechanical Advantage for our simple compound machine was 0.961. Once we were done building our project and making sure that it worked every time we tested it, we presented our completed compound machine (bottom image on the left) to the class and submitted our whole project documentation to Mr. McGarrah for a grade.