I figure I might as well jump on the bandwagon and share a few pictures of our robot:
This is version 2.0 of our robot, Talus.
Please feel free to give comments, suggestions, or ask questions!
For a quick spec sheet:
[LIST]
*]12 (guarenteed) Sack Load. We’ve gotten more
*]Under 15"
*]High Goal Capability
*]Descoring Capability
*]Macro-ified (lift and dumping operations)
[/LIST]
Im having issues viewing images 2-5…
Ah, silly little sharing permissions :o
Should be fixed?
I’m not the only linear lift! WOOHOO!
woah thats better
but DANG thats a lot of stages on your linear lift. That should lift around 40 inches. Do you have issues with friction? What gear ratio is your linear lift at? reminds me of currahee
Talus 1.0 had 4 stages and was about 1 inch to high to fit under the trough. We had planned to be under the trough, but hadn’t properly accounted for space for the chain and each tier to settle on the ground. If we just chopped off the top inch or so, we wouldn’t be able to reach the high goal. We decided to shorten everything and add a fifth tier. Now we can go way over the high goal 
. As far as friction goes, you just have to keep all of the sprockets and chain clear of any parts. We have to make sure that there’s not too much strain on the axles. In short, you just have to tweak the lift until yu get optimal perfirmance. There were all kinds of bugs when we frst assembled it. We can reach the trough in about 2 seconds. 24T driven and the big one is 30T. We are currently using 4 393 high speed motors.
Correction: Version 2.0 has 4 tiers now instead of 3 in version 1.0. The c-channel farthest to the right looks like a separate tier but is actually bolted to the chassis as the base of the lift.
ok so here is the explanation of our lift.
The green circles are sprockets. The blue long parts are the 1X5 c channel. There are slides between them but it is easier to see without them, so they are not included. The red line is the rough path of the chain. The black square is the point where the chain is affixed to the top stage(by screws through the chain).
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The sprocket on the bottom is held out by the chassis so that the front chain(furthest to the right is vertical. The chain crosses through the center of all of the stages except for the tower on the ground and the top tier. The motors would be on the left side of the pic. as the chain is pulled down it shortens the distance between the back and the front stage. The only way for this to happen is for the stages to slide past each other. Then on the way down the lift is pulled down by the motors as well. In this way the chain is a constant length like it needs to be.
for reference the lift in the pic. is fully extended. This is how our lift works there are just many more of the middle stage in ours. It is not nearly as complex as it seems once you have the actual thing to play with.
I will see if i can get a video up soon…
Would people like a video that explains the lift in more detail?
Ask if you have any questions! 
There are a ton of explanations on multistage lifts on topics with Titan/1103 currahee
Here’s a link to my (in)famous animation that I did to explain 1103’s lift. It has the spacing between the three stages deliberately large so that you can see what is happening.
(click on image)
no it would not work because it cant reach high enough to get to the high goal and still pass under the trough. I don’t see how the lift in the video would work because the chain does not say the same length.(I just don’t see it).
The principle of the two lifts is the same, the major difference is that the driven sprocket on (ours) is on the ground level/does not move whereas yours is on the first tier. etwangboy’s design is conservative on chain, and makes a little more sense upon first glance. 1103/7702 design has the gearbox on the ground tier, which means you have to have chain throughout.
i never said that that would not work. I simply said that i don’t see how it would work. The design is not a compact as ours. I was saying that it was not the best choice for this game because to get to the same height it would be much thicker.
I’m going to temporarily revitalize this thread to make a couple of announcements. Half of Team 7702 has graduated and the other half (Smiles1217 and I) are seniors this year. We have also expanded and our team numbers this year are 7701 and 7701A. Since the elevator lift has been much discussed this year, we have decided to release everything we have from Sack Attack. This includes all of the CAD, pictures, programming, and design notebook. You can access it on Google Drive via this link. I’ll be quick to admit that the documentation, design, and programming is not of the greatest quality (and two years old).
