pic: 2009 Mecanum Hub - Team 1595
 

Re: pic: 2009 Mecanum Hub - Team 1595
 

Hope you're ready to re-CAD it from scratch on kickoff day :ahh:

I'm having trouble visualizing the full wheel, any chance a photo of that could be posted? It seems like the rollers would interfere with the roller-mount supports (the angled struts coming off of the roller mount flanges).

Re: pic: 2009 Mecanum Hub - Team 1595
 

According to Rule R27 from 2008, you can CAD all you want before build season, as long as nothing gets built. Unless this rule changes, having this CADed now shouldnt be an issue.

Re: pic: 2009 Mecanum Hub - Team 1595
 

The paragraph above <R27> states the spirit of the rule. Though it's not 'technically' a rule, it's still in the rulebook and still explicitly governs as such: (emphasis is mine)

I do not mean for this to take away from the discussion of the design itself, and apologize for that :o

Re: pic: 2009 Mecanum Hub - Team 1595
 

Rules aside, that is a beautiful looking hub, I can't wait to see it with rollers. I noticed you had some extra support between the spokes, what's your reasoning behind that?

Re: pic: 2009 Mecanum Hub - Team 1595
 

Those are very cool looking. Hope you can find someone to machine them.

Is not andymark going to release an updated version of the mecanum wheels this year? I know a lot of teams did not like the thin sheet the old ones are made of.

Re: pic: 2009 Mecanum Hub - Team 1595
 

Rules aside (as you can argue either way), there is one other issue. Mecanum is cool, but don't make design decisions before Kickoff. You don't know what the game is, or if mecanums are going to be a good option. (Or even if you can get that 5-axis CNC...) If you lock in now, you may easily be at a competitive disadvantage come competition.

Re: pic: 2009 Mecanum Hub - Team 1595
 

:yikes: Pretty! Do you have any back up solutions if you don't gain access to a 5 axis cnc?

And as far as I understand the intent of the rule and clarifications last season, if you were to make the drawings publicly available on Delphi white papers or any other viable source, then you would be able to use the same drawings. ( I.e. nothing but dewalts )

Re: pic: 2009 Mecanum Hub - Team 1595
 

Any reason you are using a key instead of hex?

Re: pic: 2009 Mecanum Hub - Team 1595
 

Of course, that may be a moot point if the new "no metal parts allowed" rule stays in play... :rolleyes:


-dave



.

Re: pic: 2009 Mecanum Hub - Team 1595
 

They'll just use wood, if it's strong enough. Of course, at that point, the "freshman on a wood platform" is probably the best robot, as the controllers won't be allowed.:D

Re: pic: 2009 Mecanum Hub - Team 1595
 

Okay Dave,
I think I have the structures, motors and the power source worked out. The controls are going to be very interesting though. May have to check out a "Idiot's Guide to Programming with Rope" from the Library in Alexandria.

Re: pic: 2009 Mecanum Hub - Team 1595
 

I have just uploaded the hub with the rollers finished. If we do not get a 5-axis we will just use our previous mecanum design. We have had mecanums for the past three years. This is just a significantly lighter way of creating them. Will post pics of old ones soon.

We are in no way locking ourselves into these hubs. We will not request them to be manufactured until after we know the challenge and have evaluated the advantages and disadvantages. For overdrive we seriously considered not using them, but decided the maneuverability we would gain we more than make up for the speed loss when trying to pick up the ball.

Re: pic: 2009 Mecanum Hub - Team 1595
 

You know, I have a copy of that book in my room, I was going to go with Pigeon over IP protocol personally ^_^

Seriously guys, gorgeous wheels. Would you really need a 5 axis cnc mill to get them done? If you accept that the interior wont be as pretty you could do them with a mill by hand. But hey, if your sponsor wants to make em for you I say what better advertising for them eh?

Re: pic: 2009 Mecanum Hub - Team 1595
 

Nah... we'll just program dna and rat brains to control the robots this year.

Completely organic game: First alliance to eat all the food items on the field wins. :ahh: Of course some teams will opt for herbivores, some carnivores. Rule: no eating the other robots.

Better start working on getting those biomedical sponsors...