I was wondering if their were any teams that tried a continuous elevator powered by chain before? For a little detail, continuous fits the needs of this game a bit better in our eyes because to be under the 2 ft 4 in stage height you need to maximize the length of each stage if you are doing a stage+carriage climb. To do this, the stage travel length has to be longer than the carriage travel length, which means cascade is no longer an option. Now, we want to use this elevator to climb, and a continuous belted elevator seems that it would introduce an insane amount of skipping. A rope powered continuous would add too much variability as we cant power it from the center, we need to power it from the sides (the note travels through the center). SO, with context out of the way, would a continuous 25 or 35 chain elevator where the run starts and ends on the carriage be a good idea (think like how Spectrum 3847 did their belt run in 2023 but with chain)?
2015 game was good for this type of mechanism. We did a chain elevator that could cycle non-stop. However totes and a bin are not the same as carrying a whole robot up and down.
The hardest part was getting the “Claws” to mount to the chain and not interfere with the sprockets as they passed by. In the end we made a small metal chain link that had a tapped bolt hole on the top. We have remade these several times for various things. Putting those on both chains at an event level let us attach a plate with the claw across to both sides and keep them in sync.
We had to angle the whole elevator back slightly to help prevent the totes or bin from pulling the chain too far off the sprockets. Below is another view from inside the robot up close.
i think it would be possible but it adds quite a bit of weight compared to something like a belt or rope elevator. if you decide to go belted continuous i would suggest reading 4414’s elevator writeup for their 2023 bot
First, I see no reason you couldn’t use chain for a continuous elevator. Chain is probably going to be a bit thicker than belt which might take up some extra space, and you’ll need to use a relatively large drive sprocket to avoid skipping, but it should be doable.
Now let me question your assumptions. Why does your carriage travel need to be shorter than your stage travel? Every stage needs overlap and there’s no reason the carriage needs more or less overlap than any other stage. Why are you assuming belts will skip? Skipping can be solved by larger drive pulleys, or using bearings to push the belt into drive pulleys, and standard HTD belts can hold hundreds of pounds. This is not to say you don’t have good a reason to use chain, but if you’re already experienced with a belt or cascade elevator it might be easiest to address the perceived problems with those than open a whole new can of worms.
Oh, yeah and if you are trying to get every stage to have the same travel, but for some reason the carriage must ride on a larger section of tube than other stages, just make the tubes it rides on longer.
I hate to say “its just how the geometry works out” but to ensure we go below 2’ 4" and can extend as far a possible, “its how the geometry works out”. The thought of going with chain is mainly due to a) bad experience with belted elevators last season and b) the idea that chain and sprocket will be less likely to skip due to a deeper engagement of the sprocket teeth and the chain vs the teeth of belt and a pulley. However, I haven’t really considered using belt and implementing a bigger drive pulley and using bearings to contain the belt better would help in a climbing application (I’m sure it will). Thanks for the suggestions! My and team and I shall consider them.
