Fastest linear lift?

What do you think is the fastest linear lift?
DR4B? Danny lift?

Rack and pinion jk

“Fastest” would probably be a catapult.

It will just depend how light the lift is, how much rubber band compensation there is, how many motors it has on it, how much internal friction there is, and what gear ratio is used.

Well actually, rubber bands have no effect on the speed of a list because any you put on to make it go faster will decrease the speed at which it lowers.

You are correct, I was only considering the upward speed. Although i would be interested in whether the elastic compensation that ideal enough to have an identical effect both up and down. I imagine with real world motors and elastic, one direction will be effected more.

The best kind of lift is a linear slide lift like they use in FTC

My brother is considering a cascade lift, but I’m not sure how fast the lift will be.

Why use lifts when you can use flywheels?

lol

@SMHSRobotics seems legit

Wouldn’t an infinite reverse infinite bar be the fastest linear lift?

Not if you are trying to see how fast it takes to reach it’s max height. In this case there is no max height. But that would be an amazing build lol

It would take the same time to reach max height as a single 4 bar, assuming no friction and weightless bars and all that jazz. Obviously this isn’t a viable build (can I get infinity c-channels, please?), but I think a 4 bar is faster than a scissor, from my meager experience with massive lifts.

+1

So to summarize:
DR4B

  • Efficient
  • Fast
  • Tall enough
  • Probably the best choice
    DR6B
  • Slightly worse than DR4B in every way, but:
  • Taller than DR4B
    Elevator/Cascade
  • Theoretically the best, but:
  • Vex components make them extremely inefficient
    Scissor
  • Requires lots of torque at the bottom, less at top. Therefore:
  • Slow
  • Unstable
  • Difficult to build well

Anyone thought about a 6 or 8 bar while using the drive base to compensate for the front-back movement? I bet with a potentiometer and encoders it could be automatic and very accurate.

For my internal stacker design the lift needs to stay straight with the stack. I cannot think of a way to internally stack without a straight up lift. Would probably work with a non-internal stacker tho.

This makes the mathematician in me cringe.

Anyway there are a few options but DR4B/6B look the most reliable and efficient. Look at some of the BNS robots from worlds this year. They were very fast and lifting to roughly the same height we’ll be seeing in ITZ.
That being said if you want to focus on mo-gos for early season a 44 round up type design might work very nicely.

“Can I get the limit of 1/x as x approaches zero c channels, please?” is an awful lot bulkier.

no ones thinking of the quadruple reverse 4 bar, which i may or may not be revealing

In vex I would say it’s a wash between r4:6db and scissors in terms of speed. Yes it takes a but more “umph” when starting the scissors, but mid asscent they blow by every other lift. Really the key for this year is how do you package your lift to get the quickest placement onto the mobile goals. This makes me lean a bit to the scissors for what I’m calling the “drag bots” and to the r4:6dbs for the “field runner bots”.