Hello, I’ve been seeing people put 4-bars on their robot to lift the rings up to the high goals. I was wondering if there was a kind of lift that goes straight up and down vertically that can lift a lot of weight?
Try searching on cascade or elevator lifts
Here’s one
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Could you tell us what you mean by 4-bars? Maybe an image?
Your looking for a dr4b. Search it up on the forum and there are a lot of great resources on them.
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Personally, I would recommend a QR8B. (Feel free to look that up on the forum as well)
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Why would you need that much height? It seems complicated for no added benefit
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Great, thank you! Just and FYI, our team would be using this in high stakes to lift rings (and maybe our whole robot for endgame), would this lift be able to carry that much weight?
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That solely depends on how many motors you use to power it
if you use all aluminum it could be light enough for 1-2 motors for the lift. I would build one and test it with a bundle of steel.
Theoretically, could we do a PTO from the drivetrain motors to get more power? like some teams did for the high hang in over under?
You can do anything theoretically (theoretically I could build a V5 drow-n and fly up to the 3rd tier).
But yes, PTO-ing 6-8 motors is definitely a lot more power than 2 motors.
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Actually, theoretically, you couldn’t build a drone using V5 motors. They do not have enough power to lift it’s own weight. I have done the math and a team member has actually attempted using a 3d printed propellor.
I see what you did there
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Really? I ran some calculations, and found it was possible with an 18in blade with the right pitch (or slope).
I can try to build one, but we don’t have workshops till school starts and they’re very short/limited (usually all dedicated to bot-building).
I’m sure he lifts 
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this is what we are doing for our gravity scorer. it works really well so far.
Could we a drow-n kit for VEX air?
Do you mind sharing your calculations?
My attempts looked at using 3600 rpm to minimize weight using the 3600 rpm cartridges from spin up. Also I didn’t want to use external gear ratios which would add more friction.
Weight of a motor is 0.155 kg which means we need 1.51 N of Thrust. I went based on the assumption that the motor has 11 Watts of power output and .7 efficiency of the propellor, which means that the propellor needs to be about 1.6 meters. And that doesn’t take into account the weight of the propellor.
If you don’t mind sharing your calculations, I would be curious to see how you got 18 inches. Also I have access to our workshop over the summer, so if you send me CAD for your proposed drone and math that supports it will work, I’m happy to try it out over the summer.
Our attempt the propellor spins fast enough that it has cut my hand when I was testing it and if the propellor flies off the end of the axle it hits the ceiling, but does not lift the motor.
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