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Hovercraft B/C

Posted: August 31st, 2017, 12:20 pm
by bernard

Re: Hovercraft B/C

Posted: September 5th, 2017, 8:19 am
by 0ddrenaline
Paraphrased changes from last year

Completely new rule:
Graphs and/or tables relevant to relationship between time and distance are required, as well as a diagram or picture of the device. These graphs and tables will be used for scoring.

Rule changes:
  1. Old: Device must have a length of 15.0-30.0 cm, a width less than 19.5 cm, and a height of less than 20.0 cm
    New: Device must fit in a 40.0 cm x 40.0 cm x 40.0 box while levitated

  2. Old: Propeller shielding must block a 1/4" dowel from entering
    New: Propeller shielding must block a 3/8" dowel from entering

  3. Old: Participants determine the mass of the vehicle prior to the competition, and this mass is used to calculate the mass score.
    New: At the event, participants select between 0 and 16 rolls of pennies to load on their device. The 16 rolls are equal to about 2 kg. The number of penny rolls is used to calculate the mass score.

  4. Old: The track is set at 130.0 centimeters for Division B. In Division C, the event supervisor chooses a length between 100.0 and 195.0 cm
    New: The track is set at 165.0 centimeters for Division B. In Division C, the event supervisor chooses a length between 165.0 and 260.0 cm

  5. Old: Event supervisors choose a target time between 5.0 s and 25.0 s
    New: The target time is set at 15.0 s

  6. Old: Participants will be tested on history and theory of air cushioned vehicles
    New: Air cushioned vehicles have been removed from the test

  7. Old: If teams miss impound, their mass score will be multiplied by 0.7
    New: If teams impound their device, 3 points will be added to their final score.

  8. Old: Score Breakdown: 50% exam score, 25% mass score, 25% time score
    New: Score Breakdown: 45% exam score, 21% mass score, 21% time score, 10% chart score, 3% impound bonus
If there is a mistake, let me know. This summary has been posted for discussion purposes only. I excluded small changes. This is my own wording, and it's not official. Please, read the rules online, especially if you have a question about the specific wording, They're free.

Re: Hovercraft B/C

Posted: September 5th, 2017, 8:35 am
by 0ddrenaline
Oh, one more thing to note which really changes the event. Mass scores and time scores can come from different successful runs.

Re: Hovercraft B/C

Posted: September 5th, 2017, 8:59 am
by PHXcoach
Don't forget that the track width has changed from 20 cm to 60 cm.
Since the track is now much wider than the maximum hovercraft width some of the designs from last year to control the run time may no longer work.
Also the timing gates that we used last year won't work with the new track width.

Re: Hovercraft B/C

Posted: September 5th, 2017, 11:17 am
by Zioly
Nooo... my "tape a textbook into my notes binder so it doesn't fall out" strategy is a no-go this year! Slightly disappointed, but it's good to see that the rules committee thought to patch this loophole. Anyone else use this last year too?

EDIT: Realistically though, the textbook didn't help much at all in competition, since it takes so long to extract the needed information during a test.

Re: Hovercraft B/C

Posted: September 5th, 2017, 11:54 am
by kenniky
Oh, one more thing to note which really changes the event. Mass scores and time scores can come from different successful runs.
Wasn't that the same last year?

Re: Hovercraft B/C

Posted: September 5th, 2017, 12:05 pm
by 0ddrenaline
Oh, one more thing to note which really changes the event. Mass scores and time scores can come from different successful runs.
Wasn't that the same last year?
This year, teams can do one run that has a high mass score but a bad time score. Then, they can remove the mass and shoot for a good time score. They can then use the best part of each. After reading the old rules, I don't believe that was allowed last year.

Re: Hovercraft B/C

Posted: September 5th, 2017, 12:29 pm
by kenniky
Oh, one more thing to note which really changes the event. Mass scores and time scores can come from different successful runs.
Wasn't that the same last year?
This year, teams can do one run that has a high mass score but a bad time score. Then, they can remove the mass and shoot for a good time score. They can then use the best part of each. After reading the old rules, I don't believe that was allowed last year.
Is it not? Because we 100% did that at MIT

Re: Hovercraft B/C

Posted: September 5th, 2017, 12:36 pm
by antoine_ego
It seems that diodes are not allowed, so would that also apply to LEDs (could be useful for safety purposes)?

Re: Hovercraft B/C

Posted: September 5th, 2017, 12:40 pm
by 0ddrenaline
Wasn't that the same last year?
This year, teams can do one run that has a high mass score but a bad time score. Then, they can remove the mass and shoot for a good time score. They can then use the best part of each. After reading the old rules, I don't believe that was allowed last year.
Is it not? Because we 100% did that at MIT
I guess it's vague. I stand by my position but I could be wrong. At least the intentions are very clear this year.