Recursive Water Balloon Drop: A Design Process Exercise

An classroom 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. The “Recursive Water Balloon Drop” substituted a water balloon for the egg so that each team could experiment with multiple balloon drops. In addition a high speed video was taken of the impact of the structure and the balloon hitting the ground. The purpose of these modifications was to develop skill in management of the iterative nature of the design process and to use data to guide design improvement. Another aspect of the exercise was an individual concept generation phase before the team worked together to help generate a wide range of design concepts and prevent personality from dominating concept generation. Documentation was included before and after each drop to compare hypotheses to actual performance. The project was implemented with 23 students working in 6 teams, and took 3 hours of class time for the hardware portion of the project. After the water balloon project, the same teams worked on a larger 80 hour deign project carried out over 3 weeks. At the end of class a survey was administered which asked how the water balloon exercise impacted effectiveness in the larger design 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% as significant and 30% as somewhat significant. Overall, the Recursive Water Balloon Drop project was of sufficient duration and intensity that it allowed learning to occur in the areas of teamwork and the design process. Background Use of games in the classroom is an accepted pedagogical method, with many examples being in business and management education1. Games are also used in engineering education, often with an emphasis of improving teamwork, along with creativity, and are also used as an ice breaker2. Students generally enjoy these games, but they do take class time, material resources, and teacher effort. Therefore it is essential that games are structured to reach desired context and that the effectiveness of the learning is assessed. Studies have been done regarding the effectiveness of games as a teaching method in business education3, but much less has been done in this area for engineering. Verzat et. al.2 implemented an engineering design class the challenge of building structures from spaghetti and thread with the explicit goal of improving team performance and creativity in a following larger team design project. The spaghetti challenge consisted of two 45 minute P ge 26318.2 building sessions with a 30 minute group debriefing period between the build sessions. The debriefing session was implemented to improve teamwork performance in the second build session, and provide for more effective learning. Interviews were conducted with students 3 months after the spaghetti project, when the students were participating in their larger design project. Student comments indicated that they enjoyed the game and that the experience emphasized listening to teammate ideas and careful consideration of all design options presented. The student comments presented were antidotal with few statistical results were presented. This paper describes a similar effort to use games in engineering design with explicit educational objectives. In addition to improving teamwork, the objectives presented here included use of instrumentation tools in design iterations and increased creativity and concept generation. In addition, statistical analysis was performed to provide a more quantitative assessment of the learning effectiveness. The specific design challenged described in this paper was inspired by the egg drop challenge which is used in business, science, and engineering education. In the traditional egg drop challenge students are provided with limited materials and challenged with the objective of building a device that will prevent the egg from breaking during a drop from various heights. A wide range of variations of the egg drop has been implemented. Hoffman4 implemented the egg drop in a 30 minute surprise challenge in a management class. Halada5 implemented a pendulum impact tester so that an egg contest could be implemented inside during inclement weather (this approach precludes the use of parachutes, which is a “hidden” creative breakthrough in some contests). Warner6 implements the egg drop exercise in a business class to teach strategy and resource markets. He has student teams bid for various components to build there device, and thus the various teams have different building materials. Dow and Klemmer7 used the egg drop challenge to study concept generation and creativity, and illustrated the effectiveness of design iterations and learning from each iteration. Specifically they provided a control group with just 1 egg, while a group that was encouraged to iterate was provided a full carton of eggs. This was the only example found of the egg drop challenge with an explicit process of iterative design; understandably so due to the mess involved of many broken eggs. In addition, no cases were found where instrumentation was used to identify causes of failure in an egg drop project and used to improve the design iteration. Hamon et. al.8 evaluated the effectiveness of physical prototyping vs. simulation for a 4 bar linkage challenge, but this type of assessment has been lacking with projects similar to the egg drop exercise. This paper presents a classroom design exercise that extends the egg drop concept into a format more suitable for multiple design iterations. In addition, instrumentation is used to encourage students to apply analysis to their design iterations. To improve teamwork an individual concept generation assignment is completed before the first team meeting. The effectiveness of these various components are assessed in terms of their impact on a following more substantial design project. P ge 26318.3 Recursive Water Balloon Drop Exercise The “Recursive Water Balloon Drop” exercise was developed to teach students how to manage an iterative design process and use instrumentation tools to improve the design during each iteration. Other educational objectives include developing effective skills in creativity, teamwork, and communication. This project replaced a 15 minute tower building project with cookies. While the cookie tower contest was fun and served as an ice breaker, the teacher consensus was that it did not teach significant teamwork skills or how to manage the iterative nature of the design process. The 15 minute