Parameter of the Robot base

[kingsley.osei]

THanks To you all for the help, We built the robot in a square using 31in wide bu 32 inch long. Our drive train uses four motors, three wheels on each side. We were thinking about going with the OMNIWHEELS. What is special about them?

[theCADguy]

Omni wheels have a set of rollers perpendicular to the front of the wheel. This allows them to have sideways and forward movement, that doesn't require turning. You can put the wheels in an orientation like this:
| |
--
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The wheel(s) in the center can drive the robot sideways, because the rollers on the side wheel allow perpendicular movement. Considering that your center of mass is directly over the center wheels, this style of drive (referred to as slide or H - drive) is capable of excellent omni directional maneuvering.

[EricH]

Originally Posted by kingsley.osei

THanks To you all for the help, We built the robot in a square using 31in wide bu 32 inch long. Our drive train uses four motors, three wheels on each side. We were thinking about going with the OMNIWHEELS. What is special about them?

Hold up a minute. If your robot is 31" x 32", you will need to have some method of losing 3" or so for transport.

As far as omniwheels, they allow very easy sideways movement. You REALLY want traction wheels of some form, though omniwheels may be useful on the corners IFF the center wheel is not dropped.

[dellagd]

Originally Posted by EricH

Hold up a minute. If your robot is 31" x 32", you will need to have some method of losing 3" or so for transport.

Yeah, before you do anything else, you guys need to fix this or you'll be in for quite a surprise at competition.

Unless you are going to get really complicated, one dimension of your frame has to be under 28".

[jvriezen]

Originally Posted by dellagd

Yeah, before you do anything else, you guys need to fix this or you'll be in for quite a surprise at competition.

Unless you are going to get really complicated, one dimension of your frame has to be under 28".

Actually, you needn't get overly complicated to have your frame length and width >28".

[dellagd]

Originally Posted by jvriezen

Actually, you needn't get overly complicated to have your frame length and width >28".

I'm assuming they'll want the height of their robot to be over 42" tall, which I guess is not totally necessary. Regardless, I don't see why they would be unable to trim three inches. Having to severely limit your robot's transport configuration height probably isn't worth it over something like this that could be remedied and would allow much mroe flexibility later in the build process. I mean, its only what, day 6?

[cglrcng]

Not that big.------->See the video.

https://www.youtube.com/watch?v=FeVghhvw9dQ

And...Not that big either...

https://www.youtube.com/watch?v=vAiwLRGsNrE

Note: Please read ALL of the 2015 FRC rules before designing & building a Robot.

We want you to be able to play the game when arriving at the competitions, instead of having to help you rebuild it there (If we can all avoid it, OK?).

Please see The Rules, Robot Section; R3 & R4 for Transport Size & Wt. constraints. There are other rules that apply this year also (such as there is no on the field width X length constraint as long as it fits within the transport size...pits to the field, through doors, gates, etc....though there is a Max. height limit, both on, or off the field, and you must be able to setup and break down reasonably on the field within 1 minute or less, and everything must fit into that transport box size limitation for transport throughout the venue). So reading all the rules is very important...Stop building, start reading OK?

[mackenzieg]

Originally Posted by kingsley.osei

We were thinking about going with the OMNIWHEELS. What is special about them?

Omni wheels are good for extra maneuverability, but as Eric said, you do want traction wheels (at least the center wheels) on your robot.

Simbotics has a really good resource on a lot of different types of drivetrains, I'd suggest taking a look here: http://www.simbotics.org/resources/m...rain-selection


Mackenzie Glaser
Team 1261

[philso]

The learning curve for FRC is steep and long. It may be of benefit for your team to find a more established team in your area who can meet with your team. A few hours of in-person meetings can bring you up to speed with the basics much faster than asking many basic questions here. They can also identify holes in your knowledge better than the people posting here. You can then come back and ask more specific questions.

[cusack99]

So we made the standard long chassis and are fully up and running. We have our mechanism designed but with our chassis 32" long do we have to have our arms upright at the beginning in transport to stay under 42"???

[Amar Shah]

Originally Posted by cusack99

So we made the standard long chassis and are fully up and running. We have our mechanism designed but with our chassis 32" long do we have to have our arms upright at the beginning in transport to stay under 42"???

Yes. There is no concept of a frame perimeter this year, only that the entire robot fits within that bounding box for the transport configuration. Note that you can carry the robot onto the field and unfold the arms before the start of the match.

[kmusa]

The other restriction that many seem to miss is G7-C - that the starting configuration can not be in either the AUTOZONE, nor the LANDFILL ZONE. There are already questions in the Q&A if the space above the zones are included in the restriction.

[GeeTwo]

Originally Posted by Amar Shah

Yes. There is no concept of a frame perimeter this year, only that the entire robot fits within that bounding box for the transport configuration. Note that you can carry the robot onto the field and unfold the arms before the start of the match.

Or, if you want to be slick, have the robot unfold its own arms during autonomous.