My team is new to the design and construction of elevator type lifts, and we recently came upon this animation (http://jpearman.smugmug.com/Robotics/Misc/17225808_v2Hjfz#1322058158_xq42dQ7-A-LB). Can anyone give us any tips with regards to elevator design, construction, optimization, etc, or provide us with additional resources? Thanks!
). Can anyone give us any tips with regards to elevator design, construction, optimization, etc, or provide us with additional resources? Thanks!
Guess we created a monster here.
Start by reading this entire thread https://vexforum.com/t/team-1103-robot/18347/1, it’s what prompted creating the animation in the first place.
Then perhaps take a look at this one. https://vexforum.com/t/erratic-chain-lift-problems/19572/1
You may also be interested in the excellent CAD being created by Drbayer of the 1103 robot. https://vexforum.com/t/vex-1103-currahee-cad/19450/1
). Can anyone give us any tips with regards to elevator design, construction, optimization, etc, or provide us with additional resources? Thanks!
Well that animation was to demonstrate the concept of the hs sprocket and chain lift used on 1103’s robot in roundup. If you read through that whole thread about the 1103 robot you will get a pretty clear picture on how the lift works. Another elevator lift type is the rack and pinion gear lift. Team 1200 Syntax Error used it this year and it was quite successful. Here is a link to there robot:
http://www.youtube.com/watch?v=CW1P2Wl95bc
A main advantage of using the elevator style is that you don’t get the elliptical/circular (not sure what its called)movement that you do with a arm/4bar/6bar style lift. In my opinion it was a great advantage in round up because you wouldnt exactly have to position your robot to score in round up because you could just almost run into the goal and lower, unlike with a 4bar style you had to sort of position yourself. But anyways i would read through that entire thread to get a clear understanding on that lift. once you do that nearly all your questions will be answered.
Thanks for the suggestions. Sorry if I’m rehashing anything
I would also add that, although the lift used by 1103 was very successful and generated lots of discussion, there are alternatives that in my opinion are simpler to implement and may prove to be just as effective.
I love the animation. What program did you use?
Autocad Inventor, the text bubbles and final comp were then done in Adobe After Effects.
A couple of useful questions for teams to think about:
What was it about Round Up that made elevators effective? Team 1103 wasn’t the only good elevator robot last year.
What is it about *Gateway *that would make elevators effective?
I try to emphasize to the students I talk to that the robot should be a physical manifestation of their understanding of the game. In this case, what understanding of the unique features of this game leads to an elevator-based solution?
Team 1103 had a great elevator arm for there robot. They were probably one of the best teams out there. He was a Home schooler to!
Go Home schoolers!
My favorite teams:
Team 44: Green Egg Robotics
Team 3018: TECHNA PWN ROBOTICS
Team 1103: Currahee
I’d have to agree. Round Up was great for those designs because of the linear motion you got when you used an elevator. Unlike with a 4bar design you get the elliptical motion which made it a little harder to score in my opinion.
I think that gateway is a lot better for a 6bar/4bar design.
I agree with the lift mechanisms for Gateway.
A 6 Bar/4 Bar would be a great option.
An 2 stage elevator design would reach probably a max height of 22". That isn’t enough to reach the 30" goals. To reach those, you would have to make a 3 stage lift, which would use a lot of HS chain. Furthermore, with two stages, the intake would shake a lot. With three stages, it would shake even more. That’s why I decided not to use an elevator design this year, though I did last year.
the 6bar design will also give you more reach
which is good when you are fighting over the 20" goals, or when there are objects stuck between you and the goals
We have a light weight (2lb) two stage elevator that gets our intake to 31" (1 inch above the high goals) without a problem. The lift extends in 3 seconds and does not shake. It can be done. (1103 for example, his extended to 42" at the end of his hook)
The vertical lift has been beneficial in terms of defending/fighting for goals since the intake and weight is situated right over the center of the robot, decreasing the chances of it tipping.
Rick asked why linear lift was important for RoundUp, and whether those same reasons hold for Gateway. Weight centering for 30" lift applies to both.
Also note that high goals can legally be 31" tall, if they are at the tolerance limit of +1" over the 30" nominal. I wouldn’t be surprised if local competitions provided 29.1" goals if their local robots had reach issues, or provided 30.9" goals if their local robots had plenty of reach.
Conspiracy theory supporters jump in here
Ahahaha
Now if teams found out, then you would be the least popular school in that region ;p
(which is a bad thing)
Its a teachable moment (about the meaning and reason for field tolerances), and an opportunity to learn about robust design, and the benefits of being competition host, as well as the risks.
For example, a heavy robot practicing on a tile floor won’t be able to reach as high on a regulation field, because it will sink into the foam. Traction is different on foam vs foam with anti-static-spracy vs tile.
Similarly, when I see drivers resetting the field with a ruler in hand, I always kick them off, and reset all the items differently by hand without a ruler.
The responses to that must have been fun to deal with.
well, when we set up the fields, we try to set it up as close as possible realistically (no lasers to line things up ;))
we generally dont go with “use the worst possible leagal senario to see if their autonomous/arm height screws up”