Hovercraft B/C

[retired1]

The student is under no obligation to start his/her countdown until they are ready, so their motors can be fully spooled up when they do the countdown. So no problem.

[geniusjohn5]

Can breadboards be used?

[YeagerTheCat]

The student is under no obligation to start his/her countdown until they are ready, so their motors can be fully spooled up when they do the countdown. So no problem.

... ahhh, but we do want it to sit there and gradually apply power so that it can be spooling up and eat the time that way. It is relying on the motor spool up time as part of the run that worries me (eg: it probably won't move for several seconds, but it surely will after that). I am probably being about as clear as mud here.

[nicholasmaurer]

The student is under no obligation to start his/her countdown until they are ready, so their motors can be fully spooled up when they do the countdown. So no problem.

... ahhh, but we do want it to sit there and gradually apply power so that it can be spooling up and eat the time that way. It is relying on the motor spool up time as part of the run that worries me (eg: it probably won't move for several seconds, but it surely will after that). I am probably being about as clear as mud here.

If the device is still for 3 seconds or more, it counts as a failed run, regardless of whether the competitor agrees or whether it is clear the device is still spooling up. If the device is still for less than three seconds, that is perfectly acceptable under the rules.

Opinions expressed on this site are not official; the only place for official rules changes and FAQs is soinc.org.

[YeagerTheCat]

Ok! That was my interpretation as well but wanted to make sure. Appreciate it...

[YeagerTheCat]

Tangentially related, but if anyone has run at an invitational, curious about what was used as the surface. The guidance nationally was to use the floor which likely would be pretty flat, but tables with dips in them (as previously mentioned) will be in our local future.

[retired1]

You are building in a variable which for my 2 cents I do not think that it is wise.
You have to start the fans before you can start the countdown and you can not touch the craft after you start the countdown (till the end of the run).
Variables in student counting and variables in how fast the ES removes the block will happen. The ES is under no obligation to be either fast or slow or even consistent in removing the block.. Your spool up time will vary by the voltage actually on the battery.
My guess is that both of our fans reach unloaded rpm in a second or so. 9V motors with 8.4 V NiMH plus an overcharge. A 20 second run does not appear to drain the voltage that much.

[YeagerTheCat]

Oh I hear you ... lots of variables there. This is a brushless fan with a full 10 second spool up time (it is really slow), so it takes some time .

[geniusjohn5]

can breadboards be used? Please I need a clarification.

[nicholasmaurer]

can breadboards be used? Please I need a clarification.

3.g. is silent on breadboards. I would argue a breadboard is nothing but a carefully constructed set of wires. I doubt you'd have any issues - they are trying to avoid integrated circuits that act as timing mechanisms, not breadboards. Submit an FAQ if you are really concerned.

Opinions expressed on this site are not official; the only place for official rules changes and FAQs is soinc.org.