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Here's our robot being suspended from the first rung and reaching for the second. After the second rung the robot transitions to the outside of the third rung for the final climb. Speed is the biggest issue currently as the lead screw mechanism we're using is only climbing at 50 inches per minute. As crazy as it seems we're also thinking about ditching the drive train and just climbing.
Discussion
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03-02-2013 19:32
inkspell4
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
What are you using to hook onto the first rung?
03-02-2013 19:44
NOV8R
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
It's a steel spring loaded hook that pops out as the climbing shuttle pulls the robot up to the rung. Then the shuttle is free to move back the arm ready to reach for the next rung.
03-02-2013 20:15
Kevin Sevcik
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
My question is if you've tried this with bumpers. Bumpers might make that climb a lot more difficult.
03-02-2013 20:42
NOV8R
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
Yes, we've tried it with bumpers. That's one of the reasons the bot is only 15 x 24 inches.
03-02-2013 20:43
MattC9
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
That's one small robot.
03-02-2013 22:22
PAR_WIG1350
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
Video? PLEASE
03-02-2013 23:32
tickspe15
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
It may be worth trying normal wheels instead of mech's before ditching the drive train all together
04-02-2013 09:52
NOV8R
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
After thinking a lot about the drivetrain we've decided to keep it. An essential element of the design is CG manipulation. The majority of the mass is low in the robot base (4 CIMs, 4 Banebot p-80s etc). The arm is coupled to the base via a CIM/256:1 P=80 gearbox. Changing the relative orientation of the arm to the base while hanging is what controls the arms orientation to the tower. Said more simply kicking that heavy base back and forth controls where the arm goes.
This picture was meant to be a 'clue' not a 'how to'. That said, we'd be glad to answer any questions and share details with anybody trying to make a similar concept work. This has and continues to be an evolutionary process from the crazy idea we had right after kickoff. Our design criteria are something that's unique, simple and elegant. That has lead to a lot of sleepless nights but after all this is FIRST!
If you want to see all this in action we'll be at the Colorado scrimmage a week from Saturday.
04-02-2013 10:25
toastnbacon
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
This is cool! I'm kind of relived you kept the drive train, although part of me really wanted to see a sucessul robot without one. Good luck, and let us know how you do!
04-02-2013 11:27
neshera
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
A robot that climbs reliably for 30 points every match is not a bad alliance partner at all; can you pre-load colored discs, and dump them in the hopper at the top of the pyramid at the end of the climb?
This strategy may not make you the #1 seed, but will outscore lots of other teams that fail in/don't have autonomous, can only do a ten point climb, and end up only scoring five or six three-point discs in tele-op. And it could do so reliably, every single match.
This may outperform a robot that tries to do everything, and ends up doing nothing well.
04-02-2013 11:38
CalTran
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
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Originally Posted by neshera
A robot that climbs reliably for 30 points every match is not a bad alliance partner at all; can you pre-load colored discs, and dump them in the hopper at the top of the pyramid at the end of the climb?.
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04-02-2013 11:45
neshera
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
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Originally Posted by CalTran
Colored discs start behind the corresponding alliance wall. You could design a robot that could be loaded by another robot for a dump but it'd be difficult for consistency between qualifications of a robot that can fit your needs.
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04-02-2013 12:06
NOV8R
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
We initially thought about colored disk in the top goal but quickly ruled them out for the following reasons. First, the base of the robot only gets above the second rung. Second, you'd have to go to the feeder station to get them. Third, you have to have a way to transport and place them. An the list goes on and on. Translation, it's not worth the extra 20 points. In fact in figuring out match tactics within our strategy, there are going to be situations where a 20 point climb will be all that is needed. As many of you have pointed out, one of the most important aspects of this year's game is reliability. Why would you want to make the robot less reliable by trying for 20 more points? We want to do one thing well. We're not greedy.
04-02-2013 12:23
CalTran
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
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Originally Posted by NOV8R
We initially thought about colored disk in the top goal but quickly ruled them out for the following reasons. First, the base of the robot only gets above the second rung. Second, you'd have to go to the feeder station to get them. Third, you have to have a way to transport and place them. An the list goes on and on. Translation, it's not worth the extra 20 points. In fact in figuring out match tactics within our strategy, there are going to be situations where a 20 point climb will be all that is needed. As many of you have pointed out, one of the most important aspects of this year's game is reliability. Why would you want to make the robot less reliable by trying for 20 more points? We want to do one thing well. We're not greedy.
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"the base of the robot only gets above the second rung."
Not necessarily true. The base of the robot, at a minimum, gets above the second rung. It is entirely possible, though not likely, to design a robot that practically hugs the rungs and gets you as high off the ground as possible. As well, the scoring mechanism doesn't have to be at the very bottom of the robot, and I would be quite surprised if it was at the very bottom.
"Translation, it's not worth the extra 20 points."
Hugely debatable. It's a fairly reliable system, and addressing the point above, even if you're barely above the second rung, you're still closer than ever to the goal. (<36" to the goal.) To put this in perspective, 20pts of white discs would mean 2 full trips (or hoppers) with almost perfect accuracy (you can miss one shot out of 8. Meaning you shoot with 88% accuracy.)
"A 20 point climb will be all that is needed."
I cannot speak for other teams, but for our team, it would be fairly difficult to stop at the 20pt level, unless we run out of air or have catastrophic failure. It is designed fairly autonomously and will more likely than not be a 30pt or bust climber.
04-02-2013 15:31
NOV8R
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
CalTran, Your points are well taken. Perhaps the biggest reason of all against doing it is : If you can reliably show you can score 30 points every match, as soon as you leave the safety of the pyramid your dead. Every robot on the opposing alliance is going to be focused on making sure you don't get back to the pyramid. Keeping you from climbing is the same as them scoring 30 points.
04-02-2013 20:23
cmrnpizzo14
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
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Originally Posted by NOV8R
CalTran, Your points are well taken. Perhaps the biggest reason of all against doing it is : If you can reliably show you can score 30 points every match, as soon as you leave the safety of the pyramid your dead. Every robot on the opposing alliance is going to be focused on making sure you don't get back to the pyramid. Keeping you from climbing is the same as them scoring 30 points.
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I guess that I am basically saying, do you think that you could prevent a robot from getting to the largest object on the field for a long enough time that it stops their climb without sacrificing defense on what are hopefully that alliances "main" scoring robots (the shooters).
05-02-2013 08:55
Brandon Zalinsky
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
I think your mecanums might be on backwards- the rollers form a 0 instead of an X.
05-02-2013 09:24
45Auto
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
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Originally Posted by nov8r
If you can reliably show you can score 30 points every match, as soon as you leave the safety of the pyramid your dead. Every robot on the opposing alliance is going to be focused on making sure you don't get back to the pyramid. Keeping you from climbing is the same as them scoring 30 points.
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Question 2 - What do you think the other robots on my alliance are going to be doing?
Stopping you from stopping me from scoring 30 points is the same as them scoring 30 points and you scoring 0!
Either way, my alliance wins by 30 points!
05-02-2013 10:53
NOV8R
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
Good eye Brandon, Right now the drive train is not hooked up and is only dead weight to make CG manipulation work. If you're keeping up with the discussion the question is do we even need to make it work. The robot rules say you have to have a 'mobility' system. They don't say it has to be functional. As it stands now our match strategy is to position the robot at the start of the match inside the pyramid with the arm touching the first rung. Then in autonomous the robot will climb to the first rung and hang. When teleop begins it will climb to the second rung, transition to the outside and finish the match hanging in level 3. The sticky wicket right now continues to be climbing speed. During the 2 minutes of teleop it's dicey completing the L3 climb, hence starting in autonomous. We're looking at other climbing motor/gearbox combos to make the climb faster. The current climb mechanism is a 36 inch 1/2 inch 0.25 lead screw run by an AM-0915 gearmotor. That spins the lead screw at close to 200 rpm climbing at 50 inches per minute. We're looking at using a BAG motor/Vex Pro gearbox setup.
05-02-2013 11:03
Alpha Beta
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
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Originally Posted by NOV8R
The robot rules say you have to have a 'mobility' system. They don't say it has to be functional.
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On the other hand isn't vertical mobility still mobility?
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R01 Each registered FRC team may enter only one (1) ROBOT into the 2013 FRC. The ROBOT must be built by the FRC Team to perform specific tasks when competing in ULTIMATE ASCENT. The ROBOT must include all of the basic systems required to be an active participant in the game – power, communications, control, mobility, and actuation. The ROBOT implementation must obviously follow a design approach intended to play ULTIMATE ASCENT (e.g. a box of unassembled parts placed on the FIELD, or a ROBOT designed to play a different game would not satisfy this definition). |
05-02-2013 11:16
NOV8R
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
Good question Aaron. I guess I was stuck thinking of mobility in the horizontal plane. We're playing with 'how much' weight we need to make the CG manipulation work. Less weight also translates to faster climb. We are going to have wheels of some sort even though they may be static. I can see us now trying to convince an inspector where the bumper zone is if we didn't have them.
05-02-2013 14:21
Brandon Zalinsky
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
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Originally Posted by NOV8R
Good eye Brandon, Right now the drive train is not hooked up and is only dead weight to make CG manipulation work. If you're keeping up with the discussion the question is do we even need to make it work. The robot rules say you have to have a 'mobility' system.
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05-02-2013 15:25
NOV8R
Re: pic: Haven't got a clue for 'how to' climb for 30 points? Here's one
Hi Brandon, The robot is 24 x 15 inches (78 inch perimeter). It's the smallest robot we could make and get all the required components in. All the components (cRio, power dist board, battery, digital sidecar, h bridge etc) are all inside. Needless to say it's a little cramped. I'll take some pictures of the inside of it in the next few days and post them. Getting everything inside was very similar to the pictures of people trying to cram too much stuff in a small suitcase. The only thing we didn't have to do was sit on it to close the lid.
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