Presentation on theme: "Bro. Nigel Pratt Kellenberg Memorial HS, Uniondale, NY Andy Hamm Boyceville High School, Boyceville,"— Presentation transcript:
Bro. Nigel Pratt Kellenberg Memorial HS, Uniondale, NY Andy Hamm Boyceville High School, Boyceville, WI, 2011 & 2012 National Event Supervisor
This PowerPoint presentation is based on the DRAFT rules for Mag Lev The final edition of the rules found in the Coaches Manual may be different than what is found here.
Students build up to two self-propelled magnetically-levitated vehicles to pull a magnetically levitated sled Main Goal: Consistency Maximum Voltage of Any Circuit: 9V Vehicle size restrictions
Students run their cars and develop data charts and graphs of the time it takes for their car(s) to pull sleds of various mass Ideal times range from 2.0 – 4.0 seconds for regionals, 2.0 – 5.0 seconds for state, and 2.0 – 6.0 seconds for nationals. Sled is less than cm and has a standard metal hook on the front to allow connection with the impounded car.
Note a simple sled can be built with plywood and small ceramic magnets. A paperclip can be used to connect the sled to the car.
Must be between 10.0 and 18.0 cm long Mass must be no less than g Car must fit on standard Mag Lev track (see next slide) Secure screw eye (1/8 or larger) in rear of vehicle No rare earth magnets (can damage magnetic tape in the track) Car must remain levitated throughout run
Side rail height can be between cm and 5.0 cm. Track length must be at least five feet in length. Longer tracks are allowed, but only a five foot section will be used for competition. Teams can bring their own sled and track and use them, as long as the supervisor verifies the track dimensions (width, length, etc.), similar to the ramp in gravity vehicle.
This home-built track was used at the 2012 national tournament at a total cost of less than $30 and was not damaged in transport from Wisconsin to Florida via UPS. Dont mind the slight crookedness…this was fixed after the picture was taken. The side walls should be perpendicular with the track. Track is only five feet long…easier for transport and storage The instruction manual for creating this track will be available on the Mag-Lev page on the national website
Before the first run students adjust the mass of the sled that they will pull based on the ideal time. Competitors get two runs with one or two cars in no more than eight minutes (different from trial rules in the past of only five minutes). The sled mass cannot be changed between runs Time should be measured using photogates if possible. If stopwatches are used, three timers should be used and the middle time scored to only the tenths place (drop the hundredths digit) Sleds must be able to accommodate a ¼ wood dowel for photogate timing.
Vernier photogates were used with lasers.
There is also a written test on magnetism. Topics to be covered include: Magnetism and Magnetic Fields, including Common Applications Magnetic Force Electric Motors and Generators Motion of Charged Particles in Magnetic Fields Magnetic Fields around Current-Carrying Wires MagElectromagnetism and Solenoids Medical Applications of Magnetism Historical Development of Magnetic Theory & Technology Superconducting MagLev Technology Transportation Physics of Superconductors and Common Applications
A common concern is the cost of this event Many schools already have Mag-Lev tracks My school in Wisconsin had one in our old Technology Education room that met specifications. A neighboring school has three tracks that all met specifications. The cost of making a track can be shared with the Science and/or Technology Education Department I use my track in Physical Science and AP Physics B classes Instructions for making a track to meet all specifications for less than $30 are available on the national website. One of these tracks were used at the National Tournament in Successful cars can be made inexpensively My students car was the WI Div C state champion in 2011 and only cost $9.50 for the parts not including two 9V batteries. Students can be very creative and build a successful cheap car!
One common concern with this event is that too many cars get stuck in the track and cant travel down the entire distance…the following modifications were made to last years trial rules: Students have 8 minutes instead of 5 minutes Students can bring and impound their own track and sled to use, after verification by supervisor Students are given an ideal time and adjust their sled mass, allowing teams to get down the track and get in Tier 1 even with very light sleds
Make sure your students closely investigate why their vehicle stops in the track. Is the car really stuck due to a width issue, or is the car twisting in the track? Is their motor/battery/propeller combination too weak, not giving their car enough thrust to overcome some friction on the side walls? Is the cars center of mass too high and the stability of the vehicle low during its run, causing it to tip over? The most successful teams in this event know their cars, how to modify them, and understand how balance, torque, and center of gravity are all related on their specific car(s).
Great website from New York, but beware of the rules changes for 2013: Many resources will be posted on the National website as well, including a sample scoring worksheet and EXCEL spreadsheet for use by event supervisors to compute team scores and an impound checklist.
During the year, feel free to contact Andy or Bro. with questions!