Group 074-03: Center of Mass

For this design project, we plan to experiment with the primary concept of center of mass. This idea will be transformed into three, fifty-minute experiments. One experiment will be designing a structure with multiple tiers. Various sized weights will be distributed throughout the structure, and the main goal would be to calculate the center of mass. Another experiment would utilize the 3D printer. Creating a small teeter-totter with the printer and rolling different objects (toy cars, marbles, etc.) will display the importance of the center of mass. For the third experiment, we will demonstrate how mass affects balance. We plan on teaching middle school classes the fundamental physics and advanced problem-solving skills with engaging exercises. Some challenges that may be faced is our ability to get our message and the directions across to the audience. Some significant tasks are going to be to construct the props for our experiments and evaluating the necessary calculations. The fina

In the first week of the project we will be generating ideas and thinking of the main concepts we would like to achieve through the experiments. Some things we would like to accomplish through the experiment is to create a cheap, safe, engaging, and educational experience for a middle school audience.

Through week two, we are finalizing our top three decisions for the eventual experiment we will conduct. We have began coming up with a decision matrix to assist us in deciding. Our choices have come down to a gear ratio, a center of mass, and a pneumatics lab. We are also working on a gantt chart to get an idea of the timeline for finishing this experiment. We plan on completing a few tasks one week at a time.

Week 3 was very productive. The project proposal has been completed and uploaded to the blog. From three experiments, we have narrowed it down to one. Our final decision is the Center of Mass lab. This lab will be split into three, 50 minute experiments for a middle school class. We have started putting together designs and sketches for the labs. Next week we will begin prototypes and may get an attempt at the 3D printer.

In week 4, we have developed a testing plan and have acquired the necessary materials for the hanging masses part of the experiment. Two dowel rods, a block for the main balance tree, and carabiners. We have began designing the mold for the 3D print and plan to have that finished within the next two weeks. Next week, Jake plans on being certified for tier 2 and 3 training, so we can make the necessary cuts and notches into the wood.

In week 5, we made the necessary cuts to our wood and our "tree" was assembled.  There was a minor setback that the hooks do not fit entirely in the notches. We will have to find a way to shave the wood around them, expanding the circumference. Also, this week, feedback was also provided to our project from another group. They suggested it may be difficult to transport and store our large materials. Another suggestion was that not every school would have a 3D printer, which is necessary for our third lab. We will consider these suggestions and begin to think of some solutions. In week 6 we will begin to start getting together our second and third labs, preparing for the overall testing in the upcoming weeks.

In week 6 we have began drafting our student and teacher lab manuals. These manuals will describe everything required for the experiment including, equations, data charts, procedures, and materials. We added the notches to our "tree" for the weights to hang in place. Our 3D printed balance beam is now in the works and should take about 8 hours to finish. Until then, we will wait.

Our 3D printed balance beam has finally been printed! However, after multiple tests and playing around with, we have decided the beam does not serve the lab well enough. It is too small and difficult to work with. By the end of the week we will try and figure out an alternative prop for our balancing experiment.

As week 8 comes to an end, all of our prototypes and testing have been completed. Regarding last weeks dilemma where we decided to drop the 3D printed balance beam from the experiment, we have found an improved substitute. We agreed it would be best to insert another loop on the other end of our weight "tree." Not only does this, now, multipurpose structure lower the cost, but it also makes the experiment more accessible (for those who do not have a 3D printer).  This ended up working a lot better. Having two carabiners on the ends also made the lab easier to assemble. As you can see; we just used two chairs in the classroom to hold the beam, and every classroom has chairs.

As week 9 comes to an end, we are basically finished and ready to show off our experiment. All that is left to do is complete our power point presentation and add some finishing touches to our lab manuals. This is our last week for testing and making any last minute changes. Also, as all great things must come to an end, so must this blog, sadly. It has been an honor and a pleasure. April 4th, 2019: May 31st, 2019:

Center of Gravity Video: https://www.youtube.com/watch?v=R8wKV0UQtlo Khan Academy Center of Mass Link: https://www.khanacademy.org/science/physics/linear-momentum/center-of-mass/a/what-is-center-of-mass Hyper-Physics Center of Mass Link: http://hyperphysics.phy-astr.gsu.edu/hbase/cm.html Khan Academy Torque Link: https://www.khanacademy.org/science/physics/torque-angular-momentum/torque-tutorial/a/torque

How long will the experiments take? There are three labs that should each take approximately 50 minutes. How much will the whole experiment cost? Around $15. How is center of mass used today? The center of mass is used all the time. It is the main idea behind balance. The center of mass contributes to the human body as well. Without it, we would be unbalanced, slouching, and falling. What is the audience age range? This experiment is made for middle school and early high school students. Is there any assembly required? There is some assembly required. All necessary weights are provided. Are there similar products to those in this experiment anywhere else? There are some similar products to this, however, non with the same intent of our design. Our product is made to work to the user's preference with a variety of notches and the flexibility to be hung almost anywhere.

Elevator Pitch Jacob Hobaugh Our project is centered on teaching middle schoolers the concept of the center of mass. We teach them the background in the pre-lab questions, and then run them through the fundamentals in the first lab using cardboard cutouts. The next two parts take it to the next level with showing them a variety of balancing of masses across a multi-level balance beam and rolling an object down a ramp with an unusual center of mass. In the post-lab they will explain what they have learned, and what they can apply it to in every day life.

ENGR 113 - Spring 2019 First-Year Engineering Design “Group 3 Project Proposal” Date Submitted: April 18, 2019 Group Members                     Ella Johnstad, egj28@drexel.edu                                                Jake Hobaugh, jgh59@drexel.edu                                                John Cebollero, jmc663@drexel.edu                                                Quinn Foerter, qjf25@drexel.edu Technical Advisor                 Dr. Roger Marino, rm88@drexel.edu Abstract: For this design project, we plan to experiment with the primary concept of center of mass. This idea will be transformed into three, fifty-minute experiments. One experiment will be designing a structure with multiple tiers. Various sized weights will be distributed throughout the structure, and the main goal would be to calculate the center of mass. Another experiment would utilize the 3D printer. Creating a small teeter-totter with the print