Hovercraft B/C

[HeatherFeather]

I cannot tell if this motor is brush-less or has a brush - there are no labels, no way to see inside of it. How can judges tell what motor is being used? We just have a bunch of spare parts of printers/computers etc. do not have $ to go buy something fancy.

Also, it is ok if only one motor (instead of two) is used?

[ashmmohan]

I cannot tell if this motor is brush-less or has a brush - there are no labels, no way to see inside of it. How can judges tell what motor is being used? We just have a bunch of spare parts of printers/computers etc. do not have $ to go buy something fancy.

Also, it is ok if only one motor (instead of two) is used?

How many wires come out of the motor and what color are they? One motor is totally fine.

[HeatherFeather]

One more - how rigid does the mesh around the propellers need to be? Will the shielding be pushed on with the dowl? with what force will the dowel be pushed? or is there no pushing involved - purely looking at size?

[HeatherFeather]

How many wires come out of the motor and what color are they? One motor is totally fine.

Two wires - red and black - not sure if those were the original wires or not though, just soldered on.

[ashmmohan]

How many wires come out of the motor and what color are they? One motor is totally fine.

Two wires - red and black - not sure if those were the original wires or not though, just soldered on.

The motor is almost definetly brushed unless it has a buiilt in IC which would mean it is a fan motor and thus legal so you are in specs

[meierfra]

Teams can change the mass between runs to change their speed and thus time.(IIg) There isn't a spot on the scoring spreadsheet to change the mass.

It seems like it's possible to choose the better Time Score and still have a worse Final Score if the Target Time is small and the team gets closer to it by lowering their mass, and thus their Mass Score. That doesn't seem right. Maybe there should be a Vehicle Score that incorporates both the mass and the time and that you can choose the greater Vehicle Score of the two runs.

We deliberately separated out the Mass Score and Time Score. The Mass Score will automatically be from whichever successful run has the higher mass - there is no need to record the lower mass from the other successful run (particularly since any penalties that impact the Mass Score apply to all successful runs. The Time Score is a bit harder to calculate due to potential run-specific penalities, which is why there are spots to record both successful time scores. The Final Score will always be calculated based upon to best combination of the Mass and Time Scores. A technique that this allows is to do one initial run with a light vehicle that gets a very good time score, then another run with additional mass added to the vehicle to try to maximize the mass score. Hence, we are encouraging flexible engineering that can be adapted on the spot!

So what you're saying is that the "mass of the vehicle" should be defined as the heaviest mass of the two successful runs. I find 6a to be ambiguous. The top of the fraction is just "mass of the vehicle," and no where is this defined. Even though the bottom says "mass of the heaviest successful vehicle of all teams," I didn't think that implied anything about how I selected the "mass of the vehicle." I interpreted the rules as saying use the mass of the vehicle during the run with the best Time Score.

I think this can be misinterpreted and I will submit an FAQ tonight.

[lianahubanks 24]

so after reading the rules multiple times i couldn't find how long it should take for the hovercraft to pass the track does anyone know how long it needs to be??

[kenniky]

Teams can change the mass between runs to change their speed and thus time.(IIg) There isn't a spot on the scoring spreadsheet to change the mass.

It seems like it's possible to choose the better Time Score and still have a worse Final Score if the Target Time is small and the team gets closer to it by lowering their mass, and thus their Mass Score. That doesn't seem right. Maybe there should be a Vehicle Score that incorporates both the mass and the time and that you can choose the greater Vehicle Score of the two runs.

We deliberately separated out the Mass Score and Time Score. The Mass Score will automatically be from whichever successful run has the higher mass - there is no need to record the lower mass from the other successful run (particularly since any penalties that impact the Mass Score apply to all successful runs. The Time Score is a bit harder to calculate due to potential run-specific penalities, which is why there are spots to record both successful time scores. The Final Score will always be calculated based upon to best combination of the Mass and Time Scores. A technique that this allows is to do one initial run with a light vehicle that gets a very good time score, then another run with additional mass added to the vehicle to try to maximize the mass score. Hence, we are encouraging flexible engineering that can be adapted on the spot!

Hmm...

so let's say you have a run with a low MS and high TS, and a second run with high MS and low TS

You would be able to use the high MS and the high TS in your final score?

Interesting.

[chalker]

so after reading the rules multiple times i couldn't find how long it should take for the hovercraft to pass the track does anyone know how long it needs to be??

Check rule 5.f.

[chalker]

So what you're saying is that the "mass of the vehicle" should be defined as the heaviest mass of the two successful runs. I find 6a to be ambiguous. The top of the fraction is just "mass of the vehicle," and no where is this defined. Even though the bottom says "mass of the heaviest successful vehicle of all teams," I didn't think that implied anything about how I selected the "mass of the vehicle." I interpreted the rules as saying use the mass of the vehicle during the run with the best Time Score.

I think this can be misinterpreted and I will submit an FAQ tonight.

Hmm...

so let's say you have a run with a low MS and high TS, and a second run with high MS and low TS

You would be able to use the high MS and the high TS in your final score?

Interesting.

Nowhere in the rules does it associate MS with particular runs. You simply have a MS associated with your vehicle. If the mass changes during the competition, the MS goes up as long as you have a successful run with it.

Note we've posted an official scoring sheet (per rule 6) on the website, which per general rule #3 (https://www.soinc.org/ethics_rules) should be treated as if they are part of the rules. You can play around with it to see how the scoring works.