Heavy DR4B lift

VEX V5 General Discussion Technical Discussion
1

So our lift is made of aluminum. we have linear slides to pick up cubes. but the linear slides are weighing the lift down. we upped the power to 200% and is still no going high enough. i don’t have any pictures for you guys. just need some suggestions before the 7th of December.

Thanks.

2

What are your gear ratio for the arm, how many motors are you using, do you have any rubber bands?

3

Theoretically you can counter all weight of the lift itself with rubber bands

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4

i am not sure for the gear ratio but we are using 2 motors on the lift and yes we are using rubber bands.

5

we have 4ish rubber bands on each side.

6

‘Not getting high enough’ indicates your bands aren’t pulling with a near-constant force, look up some of the methods for triangle banding to keep the bands a balanced force.

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7

Try to add more rubber bands. Which gears do you have where the motor is or do you have any at all?

8

i will come back to you around 3:30 Thanks.

9

Just keep giving my team and i great suggestions!!!

Thanks

10

You can increase the gear ratio, shorten the arm if you want, remove parts not needed, reduce friction.

11

our gear ratio is 84:12

12

Lol there ya go

Your gears are backwards, your lift needs more torque. it needs to first power the small gear which then powers the big gear at a slower speed

13

ya i miss said that, it is 12:84

14

Why do you have linear slides to pick up cubes? a claw would be a lot lighter.

I think It’s actually supposed to be driven gear/driving gear, when talking about gear ratios.

https://www.carbibles.com/determine-gear-ratio/

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15

this is our design.

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16

oh, I would suggest making custom linear slides because they are much lighter than the steel vex ones. You should also use the 100 rpm torque cartridges.

17

how do you go about making custom linear slides?

18

You’ll probably need more if your lift isn’t working. Our lift is probably similar to yours and we have 8 per side.

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19

I think your example proves my point…

They use 2:1 as an example where the motor rotates twice and the driven gear rotates once

Regardless, for this thread you’ll want little gear to big gear. Previously you stated big to little

20

you can use standoffs and high strength bearing blocks. standoffs are just smaller than high strength shafts so it creates i slide. it works quite well