Team 766 is currently designing several ways to lift the innertubes in different ways. We are interrested in several concepts but the elevator/ forklift design seems to be leading the pack. However, our team has no experience in these designs and we are searching for the parts necessary to build the elevator/ forklift. Can anyone can give us a link to a supplier and/or a photo of a robot and its elevator. Also any tips for assembling and powering the elevator (cable, chain or type of rigging) would be very helpful. Thanks!
Edit: It looks like two small CIMs will be powering our elevator or arm
Did you look at the parts in the Igus bag? Their track system could provide a possible solution for going up and down in an elevator-like setup. I’ve seen many teams do this efficiently before.
Depending on what you want to do, you’ll have different ways of going about these lifting methods; One is the forklift type of lifter. This is usually done with chain, either in continuous paths, or all individual per section. Then there’s ideas such as elevator designs, which use scissor-type lifting… For this you could either use pneumatics, or linear actuators… or possibly have a high-torque motor at the center axis of the sicssors themselves…
Our team is staying away from scissor lifts because we do not have the tools to machine the parts necessary to make a scissor work. We prefer the forklift style over scissors by a wide margin.
We want someting similar to 1072, 245 or 111’s robots (but not as fancy) from 2005
Remember, FIRST is very safety intensive. So if you make a scizzors lift it’s going to have dangerous pinch points and FIRST is going to expect you to shield off those pinch points from people and if you don’t they will make you do so. Just remember to take that into account.
Try to plan your forklift off of a real life one. Venture to a sponsors shop and look at it or do some googling. I can suggest 8020 frame work with linear bearings - depending on your budget. We used a forklift in 2005 and was a finalist at GLR .
I think the main problem with elevators or forklifts is performance. It will be slow. I am just going from experence of the game 3 years ago with the tetras
Exactly. If you’ve only got 15 seconds, the only setup strong enough to dead-lift another robot won’t be able to go 12’’ in 15 seconds.
Try a screw-type device. They gave us a small black one in the kit. the only problem is that the threads make it extremely slow but very very powerful. There probably isn’t anything out there with coarse enough threads to make the lift go faster, and still maintain that same power.
Our team did the math with alittle help from our mentors but according to our math with a machine 85% efficeint (Geared down by a multistage transmission and 2:1 sprocket ) it would take a round about .0284 horsepower to lift a 150 lb machine 12" in 12 secs with one motor. Our mth might be wrong so dont quote us lol. the question is your bot going to be balanced enough to hold another and is the other robot’s weight going to be balanced? If your cant get the solutions for these you risk the chance of tipping urself and damaging your bot and other robots as well. Just my 2 cents of info to keep in mind.
But the tetras weighed a minimum of 7 lbs and the ringers weight about 1. So with the same power output and proper gearing you should be able to lift tubes the same height at least seven times faster.
Remember Power = Work/Time = Force (weight) * Distance/Time. I’m liking having to worry more about robot to robot interactions than just weight in my designs
If anybody has a copy of the 2004 Championship presentation called “Manipulators and Mechanisms” (Or something like that) it has a few good drawings of different ways to cable a forklift. We used a forklift in 2005 and had no problems with the speed, even with the heavy tetras. A three stage lift with all internal cabling powered by (I think) a fisher price motor and a Bosch drill transmission. The only problem we had with it was we had to switch from aluminum axles to steel because the aluminum ones got all warped, and the cable broke once or twice (it was nylon) but it wasn’t hard to restring it.
~Allison
PS - If anybody does have a copy of that presentation (it was in powerpoint) it would be splendid if you could send me a copy.
Extruded aluminum with some of the plastic slides work extremely well for an elevator; we used it in 2005, and it is high on the consideration list for this year as well.
Remember that the lifting apparatus can push against the floor directly underneath the robot being raised. There is no need for it to be a completely cantilevered structure. Think “automotive floor jack” instead of “forklift.”
Yes. That is exactly what i was thinking. It is to have a sicssors lift that is completly self supported from the ground. This means that in will be able to lift the robot relitivly quickly with the right set-up:D .
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