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MEDIA ADVISORY: Mousetraps, Rubber Bands and Bowling Balls Will Provide Power in Student Contest

December 1, 2015
Media Contact: Phil Sneiderman
Office: 443-997-9907; Cell: 410-299-7462
prs@jhu.edu On Twitter @filroy

Motors and batteries are banned in this Johns Hopkins engineering challenge

WHEN: 1:30 to 2:30 p.m. on Wednesday, Dec. 2.

WHERE: On stage in the Shriver Hall Auditorium on The Johns Hopkins University’s Homewood campus, 3400 N. Charles St., Baltimore, Md. (Media camera crews will be allowed on stage.) Shriver Hall is Building 64 on the campus map that can be viewed at this site: http://bit.ly/1PMlz2J. Parking is available in the nearby South Garage.

WHO: Forty-four Johns Hopkins freshmen from an introductory mechanical engineering course will compete. Teams of two or three students have each built devices that are designed to roll across the Shriver Hall stage and then launch a small projectile over a dozen rows of seats before landing in Row M.

WHAT: Each team’s device must be able to move forward under its own power after being impacted by a 3.65-lb. duckpin bowling ball that will be rolled down a ramp to propel each device toward the edge of the stage. The projectiles must launch after the device fully passes a “firing line” marked with tape. This line is about a foot from the edge of the stage. Each device and launching mechanism can be powered only by one mousetrap and two rubber bands—no motors, no batteries. Certain materials from the class lab and elsewhere could be utilized, but the total cost per vehicle could not exceed $15. Through a series of competitions involving two teams at a time, the student winners will be determined by which team lands its projectile in Row M first or closest to the target, which is roughly 100 feet from the stage. The projectiles will be beanbag-like Hacky Sacks, each weighing a little less than a pound.

WHY: While working on their projects, students have been learning about design approaches, potential and kinetic energy, friction, prototyping methods and other topics relevant to mechanical engineering. In addition, the project requires teamwork and careful planning, which both will be important in an engineering workplace. Because some devices may fall off the Shriver Hall stage, the students were urged to make their creations durable and reusable.

CONTEST JUDGE AND FACULTY SUPERVISOR FOR THE EVENT: Steven Marra, an associate teaching professor in the Department of Mechanical Engineering, teaches the course and will serve as judge. “This is the first experience many of our incoming engineering students have in actually designing and building something,” Marra said. “It sets the stage for several increasingly more advanced design projects they will complete during their engineering education at Johns Hopkins.” Prior to the competition, Marra can be interviewed by calling his office, 410-516-0034. To obtain detailed rules and guidelines regarding the student competition, contact Marra.

 A video about a previous Johns Hopkins mousetrap and rubber band design competition involving student-built ground vehicles can viewed here: http://www.youtube.com/watch?v=Y3DhgSXha-M.


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