June 14, 2015
June 14, 2015
June 17, 2015
Design in Engineering Education
26.1318.1 - 26.1318.11
Recursive Water Balloon Drop: A Design Process Exercise Short-‐term classroom exercises can be an effective way of teaching key elements of the design process before students embark on a longer-‐term design project. However, care must be taken that the exercises teach students effective design process methods. An exercise was developed to improve upon a popular egg drop exercise, where students build a packaging container to protect a raw egg and then see which design can be dropped from the highest height without the egg breaking. One limitation of the egg drop exercise is that it does not allow for design iterations, since students are typically provided with just one egg. Another limitation is that there are no readily available measurement tools to determine why some designs work better than others. The “Recursive Water Balloon Drop” exercise was developed to teach students how to manage an iterative design process and use analytical tools to improve the design during each iteration. Other aspects covered included creativity, teamwork, and communication. In this exercise each team of students is provided with water balloons that have been filled with the same amount of water. Each team developed design concepts for their packaging and hypotheses as to what will cause the balloon to break. The students then dropped their packages at increasing height until the balloon bursts. During each drop the event was recorded with a high speed camera. We used a Casio EX that could shoot at 1200 frames per second (fps), but with incorporation of high speed photography into iPhone 6 cameras that can shoot at 240 fps, the use of high speed photography for classroom exercises is becoming increasing accessible. Students evaluated their video footage and used the results to improve their design in the next iteration. 23 students in 6 teams of students completed the recursive water balloon drop. The exercise took 3 hours of classroom time, with an additional oral presentation of each team’s design process. Each student also wrote a reflection on what they learned during the exercise. During the remainder of the class, each team competed a much larger design project. At the end of class a survey was administered which asked how the water balloon exercise impacted effectiveness in the larger course project. The largest impact was in increasing effectiveness in the Design Process with 57% indicating a significant help, and an additional 23% indicated is as somewhat helpful. Increased Teamwork effectiveness was rated by 52% as significant and 39% as somewhat significant. Increase in Creativity was rated by 39% as significant and 44% as somewhat significant. Increase in Applying Physics was rated by 26% was significant and 30% as somewhat significant A new exercise is presented with a number of advantages over the traditional egg drop exercise. The exercise included use of iteration and high speed photography for analysis. Student survey results that the exercise had significant value in preparing the students for a more in-‐depth deign project.
Delson, N. (2015, June), Recursive Water Balloon Drop: A Design Process Exercise Paper presented at 2015 ASEE Annual Conference & Exposition, Seattle, Washington. 10.18260/p.24655
ASEE holds the copyright on this document. It may be read by the public free of charge. Authors may archive their work on personal websites or in institutional repositories with the following citation: © 2015 American Society for Engineering Education. Other scholars may excerpt or quote from these materials with the same citation. When excerpting or quoting from Conference Proceedings, authors should, in addition to noting the ASEE copyright, list all the original authors and their institutions and name the host city of the conference. - Last updated April 1, 2015