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MEDIA ADVISORY: Only Mousetraps and Rubber Bands Will Power Student Devices in ‘Cable Car’ Contest

November 29, 2012
Media Contact: Phil Sneiderman
Office: 443-287-9960
Cell: 410-299-7462

In Freshman Engineers’ Inventions, Batteries are NOT Required – or Even Allowed

WHEN: 1:30 to 3 p.m. on Wednesday, Dec. 5, 2012.

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 3 on the campus map that can be downloaded from this site: http://www.parking.jhu.edu/images/JHU_Homewood_Parking_Map_070828_1.pdf
Parking is available in the nearby South Garage.

WHO: Sixty-seven Johns Hopkins freshmen from an introductory mechanical engineering course will compete. Twenty-five student teams have built aerial vehicles that must move across elevated cables and drop a “payload” onto a target five feet below. The challenge: these cable cars can possess no motors or batteries. All movement must come from mousetraps and rubber bands.

WHAT: For a class project, each team had to design a device powered only by the energy in no more than two mousetraps and six rubber bands. Other materials, such as balsa wood and wheels, can be added, but the total cost per vehicle cannot exceed $15. Each device must move under its own power along an 8-foot-long level stretch of cable. Midway across the line, the device must drop a balloon filled with salt onto a bull’s-eye target.

THE CONTEST: Two parallel cables will be strung across a portion of the Shriver Hall stage. In a series of elimination matches, two student devices will be launched across the cables. The winner of each match will be the cable car that has the best score on the target. When the elimination rounds end, a prize will be awarded to the winning team.

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.

CONTEST JUDGE AND FACULTY SUPERVISOR FOR THE EVENT: Steven Marra, a senior lecturer in the Department of Mechanical Engineering, teaches the course and will serve as judge. “We assigned this project partly because a lot of incoming engineering students have not had much experience in actually designing and building something,” Marra said. “A lot of their beliefs about how something works on paper do not necessarily work in a real-world project.” 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 Phil Sneiderman: prs@jhu.edu or 443-287-9960.

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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