I thought of this recently, and I’m sure I’m not the only one to think of this. I apologize for the horrendous MS Paint design.
Playing Strategy
Basically, At the start of the match, it would extend itself, and stay extended, and go put cubes around pipes on the edges of the tournament ring while the Skyrise bot builds a Skyrise. Then it would park next to the Skyrise and the Skyrise bot would feed it cubes.
I haven’t had a chance to try it, as I have neither the time nor the resources, but I was wondering:
Has anybody tried this?
Would the conveyor belt stay on its track while extending?
There are two teams in Utah, 4691A/D, that have pretty much this design exactly. They use something like 10 pneumatic rams to extend it up (with the help of bands), and then it can score 4 cubes at a time on a 7 tall skyrise off the back of the lift. It also has a passive skyrise claw on the conveyor belt so that it can build the skyrise. The conveyor belt does stay on track, although they have had some problems with the chain breaking and the robot tipping over.
There might be some videos of them somewhere, it’s striking how similar they look to your drawing.
there are two robots in my region that have this very lift design and they do work very well as far as I know. the only problem I have seen with theirs is if the chain breaks then they lose their lift, or if the robot disconnects since they use pneumatics to keep the sections in place.
The general idea is sound, but the lift is impractical. Thanks for the Ideas though, it is very unique and original.
You are quite likely to whack something more than you hoped (You, your partners, your partners robot, the base, the cube in front of you, etc.), and that could be very bad…
This would take a lot of rubber bands, lifting a 5 ft lever arm from a distance of like 3 inches is unlikely at best. I tried it 3 years ago.
What we tried and have seen work effectively is a scissor lift that latches or is held up by rubber bands at the top.
Your “MS Paint design.” is better than most of mine so good job!
You also have to remember that having cubes being held by cubes is very easy to descore (that is, taking cubes off of your robot). 4442X’s scissor lift could score 5 cubes on a post in one dump, but it was very easy to take a cube off of their conveyor. One of our teams even took a cube off their hooks and put the opposite team’s cube on, forcing them to drop all of their cubes so they didn’t score for the other team.
Why would you say this? There are a few things in this design that seriously need addressing, but saying it isn’t a viable idea is horrible. I’ve seen tons of these kinds of lifts in FRC, and FTC, and I have actually seen a couple of them in VEX as well. The main difference is that this one requires multiple stages to get anywhere close to where you want it, thus making it more complex. But that doesn’t mean the design isn’t viable. It is a totally sound way to compete in this game.
However that doesn’t mean that clever engineering can’t be used to mitigate the problems that you would consider this lift to be not viable. The few problems I see with the concept that has been drawn up off the bat are as follows. Depending on how this team decides to design their robot they could also encounter some other small problems along the way as well, but its hard to tell without something physical sometimes.
The chain would need to be tensioned so that it doesn’t jump off the sprockets while expanding. This would also need to ensure that the chain is properly tensioned at all times after the lift expands. Your Tensioning systems might be the most complicated part of the robot.
Expanding motion is going to be moderately complicated, the rubber bands used to expand would need to be “calibrated” accurately to ensure the lift hit its mark every time and stayed there. I’ve personally seen many teams who pursue this design actually have the expanding motion be powered and held in place with wire tension.
Center of Gravity. When you put your lift rails up that high the entirety of a match you will experience problems with CG. This to can also be mitigated with smart component placement on the drive base, considering that most of the robot would be “empty” behind the elevator.
I am going to disagree with this as seeing as I have seen with my two eyes of this working. the two teams in my region are some of the best robots there, and they have had none of the problems you have described. they are very practical since they are probably one of the fastest skyrise builders and they can reach the full height of it. the only problems I see are what I have said before and that it probably would take a lot of time tuning to get it right. apart from that however I think that this design is quite capable as long as it is done correctly.
I’ve actually aligned with one of these teams(4169A I think?) and through finals he seemed to consistantly do 4+ cubes on a 7 tall while I did cubes around the perimeter. Aside from the match that his auton broke his chain… There are definitely bugs that need worked out and it’s a hard build, but the results can be good.
They can be good. The problem with this kind of robot is that unless they or their partner build the entire skyrise, they become very slow at scoring cubes because only one or two can be scored at a time. Then again, if a robot like this had a very fast skyrise building partner, they could score 4 cubes at a time on it. Another problem that comes with this kind of robot is that autonomous is very limited: it’s either a couple cubes on a post or two or, at the most, one maybe two skyrises. I would like to comment on how efficient these kinds of robots are though–they only lift a small amount of material up to the full height making a robot that is relatively light that can still score on and build a full skyrise. Usually, though effectiveness is more important than efficiency in Vex.
so good job!