## Air Trajectory B/C

gravedigger
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### Re: Air Trajectory B/C

QQ: For the target, we saw examples of the position on the ground as well as elevated. Do we know if there is a decision on the same.

Also if the target is going to be off center, will the distance be even number or will it be off by a few cms.

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### Re: Air Trajectory B/C

gravedigger wrote:QQ: For the target, we saw examples of the position on the ground as well as elevated. Do we know if there is a decision on the same.

Also if the target is going to be off center, will the distance be even number or will it be off by a few cms.
Both of these are clearly answered in the rules. I infer from your questions you either don't have a copy or haven't looked at them closely. There are a LOT of details you need to be aware of before you get too far into your design.

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Flavorflav
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### Re: Air Trajectory B/C

joeyjoejoe wrote:
bernard wrote:
1nxtmonster wrote:So the 5 KG weight limit...

if your design was one where there was a drop tube with a piston located at the bottom and a weight that falls and hits the piston after building momentum, would the 5kg weight be for the weight or the piston and weight?
If the piston decreases in potential energy, then it is counted as part of the falling mass.
Since the piston has to have mass, If the following statement above is correct, then this implies that every pump that is not mounted horizontally will have this problem.

Uh-Oh! The pressure chamber which houses our piston has been sealed with PVC glue to prevent it from blowing off due to the pressure. Guess we will have to rethink our design.
I just started looking at this event so I could be wrong, but it seems to me that the simple fix is to turn your pressure vessel upside-down and use a pulley to pull it up instead of pushing it down.

Also, I know that this is not the place for official clarifications, yadda yadda, but anyone have an idea about how supervisors are supposed to determine if the pressure vessel starts at ambient pressure? Would the immobility of the piston suffice?

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### Re: Air Trajectory B/C

Flavorflav wrote: Also, I know that this is not the place for official clarifications, yadda yadda, but anyone have an idea about how supervisors are supposed to determine if the pressure vessel starts at ambient pressure? Would the immobility of the piston suffice?
For situations like this, I always recommend you take it upon yourself to design your device to easily and unambiguously demonstrate it meets the specs. For example, you could have a hole in the pressure vessel that is naturally open to the outside, but once the piston starts the move it blocks it off.

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Flavorflav
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### Re: Air Trajectory B/C

Well, that would foreclose using a commercial pressure vessel, which might otherwise be an attractive option.

chalker
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### Re: Air Trajectory B/C

Flavorflav wrote:Well, that would foreclose using a commercial pressure vessel, which might otherwise be an attractive option.
That was just one example. I'm sure there are many other ways to accomplish this.

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azuritemalachite
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### Re: Air Trajectory B/C

I think most you guys are overthinking it and making it too complicated. Our team made a simple piston that draws up to have an air chamber and then you release the piston making it fall down and push the air out so the ball can fly.
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### Re: Air Trajectory B/C

azuritemalachite wrote:I think most you guys are overthinking it and making it too complicated. Our team made a simple piston that draws up to have an air chamber and then you release the piston making it fall down and push the air out so the ball can fly.
Same here. The idea of using a valve is in my opinion
Ridiculous because no piston will be 100 percent airtight. Even if it was 99 percent airtight then the air would leak out rather quickly. And the idea of storing the pressurized for any duration is illegal.

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### Re: Air Trajectory B/C

1nxtmonster wrote:
azuritemalachite wrote:I think most you guys are overthinking it and making it too complicated. Our team made a simple piston that draws up to have an air chamber and then you release the piston making it fall down and push the air out so the ball can fly.
Same here. The idea of using a valve is in my opinion
Ridiculous because no piston will be 100 percent airtight. Even if it was 99 percent airtight then the air would leak out rather quickly. And the idea of storing the pressurized for any duration is illegal.
Couldn't you use the valve to adjust the force with which the ball is launched? That could be useful when you have to adjust for different distances, maybe?

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### Re: Air Trajectory B/C

Crazy Puny Man wrote:
1nxtmonster wrote:
azuritemalachite wrote:I think most you guys are overthinking it and making it too complicated. Our team made a simple piston that draws up to have an air chamber and then you release the piston making it fall down and push the air out so the ball can fly.
Same here. The idea of using a valve is in my opinion
Ridiculous because no piston will be 100 percent airtight. Even if it was 99 percent airtight then the air would leak out rather quickly. And the idea of storing the pressurized for any duration is illegal.
Couldn't you use the valve to adjust the force with which the ball is launched? That could be useful when you have to adjust for different distances, maybe?
Valves are not very consistent. You could just drop the weight from different heights to adjust distances.

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