Course-related undergraduate projects for dynamics

Abstract

The Engineering Technology (ET) program at Middle Tennessee State University (MTSU) has approximately 450 students. Our Mechanical Engineering Technology (MET) concentration was started in 2004 fall and currently it has 220 majors. The author teaches Dynamics every spring and all MET students are required to take this course. Dynamics is a lecture course and we cover kinematics and kinetics of particles and rigid bodies in this calculus-based course. We felt it is necessary to have some hands-on projects that will help students better understand the principles and applications. The author developed the egg drop project in which the students work in teams and following the guidelines build two structures using balsa wood sticks, place an egg inside and drop the unit from a certain height so as to land on the target placed on the ground. They build two such units with and without a parachute. They are required to write a report that included the construction method, calculations and graphical presentation of the unit's height as a function of time. They also compare the calculated time of fall with the measured value and explain any discrepancy. The author derived the equation of motion and the height-time relationship for the case with a parachute as these are not readily available in our Dynamics textbook. The egg drop project of each team is judged based on the compliance to the guidelines, structure's weight condition of the egg/structure after landing, distance from the target to the egg/structure, and aesthetics of the structure. This project was a great success and students had fun working together and competing with other teams. The author briefly discussed in the class a hands-on project that would help students better understand the motion of a projectile in a two-dimensional space. Three students showed a great interest in the project and that very weekend they purchased a paintball gun and conducted some experiments at a barn. Their paintball has the capability of giving the velocity of the paintball at the barrel exit which is the initial velocity of the projectile. They built some fixture to allow the tilting of the gun so that they can measure the angle made by the initial velocity of the projectile. They were able compare the calculated range and height of the target with the corresponding measured values and compute the accuracy of their device. They were also able to make a video of their experiments. The trio made a presentation of their experiments in the class and in collaboration with the author they also participated at the MTSU's annual undergraduate symposium. Three of our Dynamics students were inspired by the Paintball Gun project and decided to build a golf ball shooter for their capstone project. These students applied their knowledge of CADD, Fluid Power, Machine Tool Technology and Dynamics, and successfully completed the project. There are numerous application-oriented publications in the area of Engineering Mechanics and we have cited two of them in this paper.1, 2 We hope our course related hands-on project will inspire the ET faculty community further and many more interesting projects will be presented at the future ASEE conferences. © American Society for Engineering Education, 2013.