Hovercraft B/C

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Re: Hovercraft B/C

Post by chalker »

Person wrote:
chalker wrote:
antoine_ego wrote:It seems that diodes are not allowed, so would that also apply to LEDs (could be useful for safety purposes)?
How would an LED be used for a safety purpose?
This is just a guess, but maybe they were used as warning lights of sorts to make it easier to see the vehicle?
I don't see how that would be needed in any typical competition situation. It's not like we are running these devices at night or in darkened rooms.

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Re: Hovercraft B/C

Post by Unome »

chalker wrote:
Zioly wrote: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.
There are some pretty obvious ways you could still incorporate a whole textbook in a binder per the rules if you think about it a bit....
I recall at one point seeing a binder with a textbook inserted into the rings by removing the binding and hole-punching every page.
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Re: Hovercraft B/C

Post by dragonfruit35 »

chalker wrote:
dragonfruit35 wrote:
antoine_ego wrote:It seems that diodes are not allowed, so would that also apply to LEDs (could be useful for safety purposes)?
Well, LEDs are Light Emitting Diodes, and they're not on the list of allowed components, so I'd assume so. Kind of an odd thing to prohibit, though.
We really don't want any type of electronic circuits controlling the vehicles. It's technically possible to make some very sophisticated timing controllers using nothing but diodes (or LEDs if you were creative).
Aha, that's true. Not sure how LEDs are used for safety anyway...
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Re: Hovercraft B/C

Post by Person »

chalker wrote:
Person wrote:
chalker wrote:
How would an LED be used for a safety purpose?
This is just a guess, but maybe they were used as warning lights of sorts to make it easier to see the vehicle?
I don't see how that would be needed in any typical competition situation. It's not like we are running these devices at night or in darkened rooms.
Yeah, that's why I wasn't too sure. Couldn't really think of anything else though.
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Re: Hovercraft B/C

Post by chalker »

antoine_ego wrote:
cuber wrote:I understand the lithium battery ban from a safety point of view, but this is super inconveniencing for me. The only way I was able to get our hovercraft running last year was with lithium batteries, anything else did not have enough power to lift it's own weight. I ended up buying quite a few, as well as a decent balance charger, and now the team has no use for them this year. Any ideas on good batteries that fit the requirements?
I am a personal fan of NiMH batteries. They are substantially heavier than the LiPOs, but are probably the best option. I use Racer's Edge batteries, but I've heard good things about Traxxas batteries as well. It's definitely a good idea to get a smart charger, meaning it'll automatically shut off once the battery is full if you plan to reuse batteries.

The nice thing about NiMH is that you can overcharge them legally, because they must be <9.0V by labels. So you can have a 9.5V - 10.0V battery and still be within the rules. The issue there is that you risk damaging the battery, so I'd cycle them every once in a while. You seem to be worried about it lifting its own weight. Note that you have 33% more surface to work with, and with the added voltage of the NiMH, you ought to easily be able to hold everything :)
Going to use this opportunity to chime in on the battery changes a bit. The rules committee had EXTENSIVE debate about lithium batteries. I personally was on the side of allowing them, however the group opinion decided to prohibit them for at least this year. While I will support that, I'll also continue to advocate for allowing them in the future. There are a LOT of factors that come into play with something like this. We've posted a policy document explaining some of them on soinc.org (https://www.soinc.org/sites/default/fil ... cy18_0.pdf ) and I'd like to point out it explicitly only talks about THIS season for this very reason.

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Re: Hovercraft B/C

Post by antoine_ego »

Person wrote:
chalker wrote:
Person wrote: This is just a guess, but maybe they were used as warning lights of sorts to make it easier to see the vehicle?
I don't see how that would be needed in any typical competition situation. It's not like we are running these devices at night or in darkened rooms.
Yeah, that's why I wasn't too sure. Couldn't really think of anything else though.
Oh, I was just thinking that they might be useful for simply seeing whether the vehicle is on or whether current is flowing somewhere.
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Re: Hovercraft B/C

Post by Ashernoel »

So I'm the rules it says the competitors place the hover on the start line wherever the super places the wood block. A change in the rules is that the track is much wider than the possible dimensions of the hover so the hover should go straight to avoid awkward collisions with the rails, but if the super places the block by a wall wouldn't this let the hover hug the wall just like last year? And then account for that force in your calculations?

How much disgression do supers have as to where they place this wood block? Does it have to be the same for all teams? Does the competitor have any say as to where on the start line it is placed? How long is it? Does the competitor have to place the hover centered behind the block?

So many questions :333
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Re: Hovercraft B/C

Post by antoine_ego »

Ashernoel wrote:So I'm the rules it says the competitors place the hover on the start line wherever the super places the wood block. A change in the rules is that the track is much wider than the possible dimensions of the hover so the hover should go straight to avoid awkward collisions with the rails, but if the super places the block by a wall wouldn't this let the hover hug the wall just like last year? And then account for that force in your calculations?

How much disgression do supers have as to where they place this wood block? Does it have to be the same for all teams? Does the competitor have any say as to where on the start line it is placed? How long is it? Does the competitor have to place the hover centered behind the block?

So many questions :333
I'm not sure if the track is wider to force the crafts to go straight, because the rules state that any contact is permitted with the rails. So you can most certainly hug the rail if you want.

As for the remainder of your questions, it's all up to the ES. I'd guess that they'd put it in the center because if they always put it to the left it'd be super troll and slightly unfair to teams who had timing mechanisms on only 1 side of their vehicle if they were reliant on the side rail. As for having the craft centered, it's not stated in the rules so no.

In all honesty I liked the event more last year, but it'll be cool to see how teams handle the increased weight.
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2018 Hovercraft Nationals - 6th
2018 Mousetrap Nationals - 6th
2018 Nationals - Team 9th Place!
2019 Astronomy Nationals - 3rd!
2019 Nationals - Team 9th Place!
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Re: Hovercraft B/C

Post by cheese »

antoine_ego wrote:
Ashernoel wrote:So I'm the rules it says the competitors place the hover on the start line wherever the super places the wood block. A change in the rules is that the track is much wider than the possible dimensions of the hover so the hover should go straight to avoid awkward collisions with the rails, but if the super places the block by a wall wouldn't this let the hover hug the wall just like last year? And then account for that force in your calculations?

How much disgression do supers have as to where they place this wood block? Does it have to be the same for all teams? Does the competitor have any say as to where on the start line it is placed? How long is it? Does the competitor have to place the hover centered behind the block?

So many questions :333
I'm not sure if the track is wider to force the crafts to go straight, because the rules state that any contact is permitted with the rails. So you can most certainly hug the rail if you want.

As for the remainder of your questions, it's all up to the ES. I'd guess that they'd put it in the center because if they always put it to the left it'd be super troll and slightly unfair to teams who had timing mechanisms on only 1 side of their vehicle if they were reliant on the side rail. As for having the craft centered, it's not stated in the rules so no.

In all honesty I liked the event more last year, but it'll be cool to see how teams handle the increased weight.
I agree that last year seems a little better. It'll be interesting considering how straight you have to have your craft go for a consistent time. You'll have to make sure it's balanced and maybe have to line it up more accurately at the start.
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Re: Hovercraft B/C

Post by antoine_ego »

cheese wrote: I agree that last year seems a little better. It'll be interesting considering how straight you have to have your craft go for a consistent time. You'll have to make sure it's balanced and maybe have to line it up more accurately at the start.
Alternatively, you could just hug the railing. I like the idea of using the 2000kg in addition to the weight of the craft. Last year we managed to build an electronic timing circuit that could get us very high accuracy in terms of timing, but with the ban on transistors and diodes, that's no longer an option.

I wonder though, will people stick to the potentiometer method this year or try to find some other mechanism. I know this is not the place for official clarifications, but could it be possible to power both a fan and something else off a motor?
Rest in Peace Len Joeris
[b]2016 Air Trajectory Nationals - 3rd
2018 Hovercraft Nationals - 6th
2018 Mousetrap Nationals - 6th
2018 Nationals - Team 9th Place!
2019 Astronomy Nationals - 3rd!
2019 Nationals - Team 9th Place!
[/b]
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