Boot Scoot Bogey. April 26, Team Members: Stuart Boyce Matt Hawkins Bradley Chase

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1 Boot Scoot Bogey April 26, 2009 Team Members: Stuart Boyce Matt Hawkins Bradley Chase

2 Abstract The whole point of this project was to test the principles of physics in creating a Rube Goldberg device. In essence a Rube Goldberg device is a series of chaotic and inefficient steps that perform a simple task. Our device was required to have at least five steps and operate in no more than two minutes. The final step of our device was required to turn on some kind of electrical apparatus. In the case of our device, we chose a small battery powered fan. 2

3 Introduction The underlying objectives behind this assignment consist of: Solve an open ended problem as a team Create a reliable, and less than functional, design to display principles of physics Have fun applying the interesting topics covered in engineering Throughout the semester the class has learned multiple laws of physics. This final project was designed with the intention of having the students employ all of these methods in a hands-on lab by creating a Rube Goldberg device that would conclude with operating an electric device. The point of creating a Rube Goldberg device is to accomplish a simple task by creating a series of extremely complex, and inefficient steps, resulting in a very inefficient transfer of energy. Examples of these laws include the conservation of energy, conservation of moment, center of mass, and much more. Design Process Throughout the design process, our team ran into many problems. We started out by brainstorming and making several simple sketches of what we wanted to build. Originally, we planned on our device being much more complex and inefficient. We quickly learned that it would be better to have a simple project that worked instead of a complex project that did not complete the task at hand. All though our device was simple, we still faced many problems in completing this project. 3

4 After coming up with our plan, we went out and found as many of the supplies that we would need. Since we had a budget we decided to make adjustments to our plan based on the supplies that we found. Most of our supplies were found at Goodwill for a very inexpensive price. After obtaining all of the supplies and adjusting our plan we began to construct or apparatus. Along the way we tested various parts of our device to make sure that each step would perform the task that it was required to do. Device The device, named Boot Scoot Bogey, was built out of Good Will s wealth of various low cost toys and gadgets. Boot Scoot Bogey was pieced together on a 2 x 2 board of wood, which was necessary to suspend the ramps and other miscellaneous objects. It all begins with an elegant golf ball. This ball will roll down the first ramp, and into a pivoting scoop. The ramp was held onto the board by high strength glue, while the outside edge of the ramp was lined with a flexible wall of duct tape, to help keep the ball rolling in a straight path. Because the ball reached too great a velocity to properly land into the scoop, a dangling hollow boot was placed in the path of the ball to create a small collision and reduce the ball s forward velocity. Having now landed in the pivoting scoop, the ball shifts the center of mass and the lever begins to drop onto the second ramp. The ball will now roll down the second ramp, which was constructed identical to the first, and collide with a second object. This second object, an industrial screw, would then fall off its platform at the end of the second ramp. This industrial screw was attached by a line of dental floss, which would transfer the tension onto the switch of our 4

5 handheld fan, and thus operate the fan. This was done by running the dental floss around a nail directly above the fan, such that the torque would be a in a direct and perpendicular angle. The equations to describe Boot Scoot Bogey s reactions are as follows: 5

6 2 x 2 Wood board - $5 Misc. Wood - $2 Misc. Good Will items - $0.30 Hand Held Fan - $1 Screws and Nails - $2 Adhesive Materials - $3 Total Expenditures - $13.30 Results Originally, we found it hard for our device to complete the task of turning on the fan consistently. The problem of the ball not rolling straight on the ramp was quickly fixed by placing multiple layers of duct tape on the sides of the ramps. The lever device also proved to be troublesome. The lever would often come out of alignment with the board, causing excess friction and also not allowing the ball to make proper contact with the scoop. We solved this problem by placing a spring around the screw where the lever pivots and between the board and the lever. This allowed the lever to stay in place when operating the device. Another problem was that the dental floss would often come in contact with the fan blade and would quickly cause the fan to not operate properly. This was solved by placing staples around the dental floss so that it would stay very close to the board and not come in contact with the fan blade. After making the necessary adjustments to our device we were confident that our device would be successful during our presentation. 6

7 Conclusions Overall, the group project was a smash success. The group flawlessly performed the objective of creating a relatively reliable Rube Goldberg device within the given deadline. The group members all learned the importance of working together and accomplishing tasks on schedule, including allowing plenty of time for error. There were many problems initially, most of which concerned the design process. There were difficulties deciding upon materials and objectives, on top of the design itself. This group specifically was fortunate in having a wide variety of available times to meet and discuss the project s direction and ideas concerning what could be done. If given a chance to re-plan this project and change details, the group as a whole would have liked to increase the complexity of the design and more extensively test the device before the day of the presentation. We all felt as if the Boot Scoot Bogey could have been more extravagant; however we needed to stick to what would work reliably given the approaching deadlines. 7