Designing a climbing mechanism for 2013... a humbling experience

[s_forbes]

After much hair pulling and uncertainty, I'm confident that we have a working solution that is reliable and will not accidentally drop our robot. We stay within the 54" cylinder with inches to spare and the mechanism looks like it will integrate smoothly with our shooting/pickup mechanisms. Now it is just a matter of detailing the parts.

This is definitely the most challenging thing I've ever had a part in designing in FRC. I'm hoping that the GDC doesn't expand the size limits mid-season like they did in 2011, I think the current rules force teams to come up with extremely innovative designs.

[wireties]

Originally Posted by pfreivald

I'd be curious to see a pneumatic solution. It seems to me that the air charge necessary -- even with mechanical assist -- is prohibitive. (That said, I'm a particle physicist by training, not a mechanical engineer, and every year I'm amazed at some (much) of the things I see in FIRST.)

Yeah - we thought we had a good algorithm using pneumatics but after calculating the air required went back to the drawing board. Our mentors are mostly EEs, we feel similarly challenged. Climbing within the rules is a daunting task!

We are now thinking of slaloming up the corner powered by a couple CIMS at 43:3, a modified rack & pinion setup and something looking like skis with a hook on the end.

[Peyton Yeung]

Originally Posted by s_forbes

After much hair pulling and uncertainty, I'm confident that we have a working solution that is reliable and will not accidentally drop our robot. We stay within the 54" cylinder with inches to spare and the mechanism looks like it will integrate smoothly with our shooting/pickup mechanisms. Now it is just a matter of detailing the parts.

Good luck. I can't wait to see 30 pt climbers. I think the top row climbers will be like the teams that have stingers. At first almost no one will have them but by champs many will.

Peyton

[Jared Russell]

Originally Posted by Tubatroopa

Good luck. I can't wait to see 30 pt climbers. I think the top row climbers will be like the teams that have stingers. At first almost no one will have them but by champs many will.

Peyton

The key difference is that a stinger is an 11" air cylinder pointed downwards. A 30 point climber is not quite as trivial to add to a robot with pre-existing space and weight constraints.

[dtengineering]

The 30 point climb is a challenge. Almost to where the points should go 5-20-40 for the three different levels. While I'm delighted to see teams "going for it", remember that it is only part of the game... chasing that last ten or twenty points might cost you more elsewhere. Consider...

Is it a better return on investment to figure out how to score all the discs into the 5 point goal and only do a level 1 hang?

It it a better return on investment to practice autonomous and have a pick-up system to allow you to score five extra discs during auto and only do a level 1 hang?

Is it a better return on investment to finish a week early and get copious amounts of driver practice in?

I'd never say don't go for it... but never lose sight of what else you could be doing with the time and resources available to you. From personal experience our "best" years were the ones where we decided to be good at one thing rather than so-so at everything.

Jason

P.S. To those looking at pneumatics... remember that you can use surgical tubing/springs in parallel with your cylinder. Start the match with the cylinder extended, and then retract it... you'll only need about half the air for that first pull... maybe none at all if you do it right.

[pmangels17]

We have had some major design breakthroughs that are as of yet semi-tested. We have confidence in our ability to not fall off. Also, I'd like to think that it is innovative, and as the lead student CAD designer for the team, I'm psyched for all the work. I cannot wait to see all the teams' ideas.

We haven't been having so many worries on the actual climbing mechanism. However, our pyramid construction was a bit rough, since the specific U-bolts we are supposed to use aren't exactly abundant on the Island, and we started off pretty racked, but we fixed it.

Expect teasers post-build season. After so many ideas going through our heads, I cannot wait to see what everybody does, and how they make it work. Good luck to everybody else, and remember to be super careful while testing your climbing mechanisms.

[dellagd]

Originally Posted by Tottanka

Basically, every single idea iv'e heard or thought of so far has a huge risk, and in most of them that won't be something we are willing to take, strategically speaking.

Than again, I have been known to miss some ingenious stuff in bots that just seemed to work for other teams. (2010 climbers, 2008 shooters/collectors, 2012 stingers...)

There is very little to no risk of falling off with our design.

I just wish we had the parts to actually build it right now.

[Big Ideas]

I worked on the problem all day with mentors and students. My hope was to decide "not gona happen" vs "can be done" so we can decode where to put effort. I think we have a solid 10 AND a viable 20. With effort the 20 may translate into a 30. If so, its a matter of team resource plus risk/reward in the game.

My feeling is that 100% of teams could do 10, but 80-90% will actually make it. 5-10% will attempt or make 20. Less than 1% of teams (who said 20 teams) will make 30. I also believe that a climb ONLY robot can't make it all the way. I will be as excited as everyone else EVERY TIME I see a 30 point climb. This is a really hard one.

[Kusha]

Originally Posted by Tubatroopa

Good luck. I can't wait to see 30 pt climbers. I think the top row climbers will be like the teams that have stingers. At first almost no one will have them but by champs many will.

Peyton

Sorry, what's a stinger?

[pwnageNick]

Sorry, what's a stinger?

This refers to a device that many successful teams last year had. It was usually a rod (often pneumatic piston) that dropped down below the drive train after the robot was on the bridge as to help stabilize the bridge and minimize rocking, making it easier to balance. It was easier to add on later in the game because it was a smaller amount of weight (~5lbs or less) and could be added in many places on the robot without too much hassle on the first day of the competition.

-Nick

[Chris is me]

I don't see thirty point hangers being added on mid season. To design them, you basically have to integrate it into every aspect of your robot design. It's one of the most challenging design problems in years.

I think it's more likely that you see teams show up to events as pure hangers and then add on frisbee mechanisms over time rather than the other way around. Though I do expect to see a lot of copied 10 point gravity hangers.

[MrForbes]

Originally Posted by dtengineering

While I'm delighted to see teams "going for it", remember that it is only part of the game... chasing that last ten or twenty points might cost you more elsewhere.

This is how we're looking at it. I don't know if we'll even do floor pickup....we have our plate full just making a short robot that can human load and shoot accurately. The 10 point hang is worth doing, 20 not so much, 30 is just a way to waste our team's time!

[cmrnpizzo14]

Originally Posted by danopia

For those of you that have ideas for a 30-point climb, would your robot be able to scale to a pyramid of, say, 10 levels without nontrivial changes? Ignore your robot hanging 30 feet in the air.

Yes, we have a design that is simple, fits a small footprint and potentially will climb to the top in <20 seconds. It should in theory be able to climb to any level without any change.

[ttldomination]

Originally Posted by cmrnpizzo14

Yes, we have a design that is simple, fits a small footprint and potentially will climb to the top in <20 seconds. It should in theory be able to climb to any level without any change.

Funny thing about that theory...

- Sunny G.

[cmrnpizzo14]

Originally Posted by ttldomination

Funny thing about that theory...

- Sunny G.

If it can make it to the top when we build it, it can make it to any level. The design does not require changes based on levels, we just have to be careful when building it. A simple error when building could provide quite a headache for us when trying to climb.