1540 WCD

Hi guys, so I’m not sure which forum this should go to so I decided to put it here. This is our first year to make a west coast drive system, and from testing it at our BunnyBot game, it has proved to be fantastic. However, for the build season, I’d like to make more improvements to it and would like opinions and how to’s.

The drive base is based off Team 221’s super light chassis with our own holes to mount the transmissions. For our competition robot, we are probably going to use their supershifter adapters as well.

These are the things I’m looking forward to change:

  1. I’d like the chains to be on the inside rather than the outside of the frame. However, I’m not sure how to put the sprockets inside the supershifter adapter.
  2. If we are unable to place chains on the outside, how would we mount the bumpers?

Any other comments and suggestions are welcome.

This is our current frame design:

http://www.chiefdelphi.com/forums/attachment.php?attachmentid=11229&stc=1&d=1324541524





In 2008 we built a bracket that attached the bumpers to the frame.

http://farm4.static.flickr.com/3027/2493952401_4eafe022da.jpg

Wouldn’t those now be illegal?

By current (2011) bumper rules, it appears that those would be illegal, but without knowing the specific measurements, it’s hard to say definitively. That’s not to say that the method is flawed, you just may need more mounts of that style to comply with rules.

Moving the chains to the inside requires a transition from dead axles to live axles. This is a non-trivial change to your current design. 221 sells a live axle bearing block if you’re looking to keep things COTS. I’m not familiar with how to integrate it with a standard Supershifter though. All the WCDs I’ve seen with interior chains use a semi-custom gearbox (standard parts with custom sideplates) so they can integrate the extra sprockets onto the output shaft.

Look at 254s gearbox. It’s a good example of how to do this.

That looks like a good start, but you’ll probably want to rethink your electronics layout. I don’t think you’ll be able to mount your digital sidecar like that because you’ll be blocking your cables coming out of the digital module (unless FIRST changes the ordering to fill the first 3 slots), and you clearly can’t bolt it down. It looks like you’ll have space in front of your PD board for the sidecar.

I can’t see everything, but will you have enough space to wire up your victors? Forgetting about wiring is so easy to do when you’re trying to make things fit.

Another thing you can do is to move the entire transmission out away from the chassis so there is a gap, and then put the sprockets on the output shaft between the transmission and the chassis rail.

What’s all the other stuff, like the pneumatics, for?

Also, how did you connect the corners - it’s a little hard to see when it’s all red.

It looks cool, though. I wouldn’t mind having a drivetrain like that this year.

Exactly what I was going to say.

973 has a few pictures on CD-Media of this.
http://www.chiefdelphi.com/media/photos/31603
http://www.chiefdelphi.com/media/photos/31604
http://www.chiefdelphi.com/media/photos/31605

Hope this helps.

EDIT: Also attached is a picture of 48 and 3193s CAD of how they setup their WCD with Supershifters.





Wouldn’t that be pretty dangerous if you don’t support the transmission properly? I have a feeling they wouldn’t respond well to being cantilevered…

That indeed is the plan for 2012. Remember that the 4-slot cRIO…only has 4 slots. :slight_smile:

That was actualy 973’s 2008 robot. However its design was heavily influenced by 294 alumnus AdamHeard, so you are technically correct.:wink:

Instead of bolting down our electronic board, we used velcro on most of the parts to hold it in place, and it worked out perfectly fine. The CAD I showed was not completed so a lot of stuff are still missing.

For wiring the Victors, our control systems person was able to make a “Wire Spine” from all the victors going to our different electrical components. Again, we did make slight modifications before we made the robot. Sadly, my windows partition is dead so I couldn’t upload the latest CAD

The chassis from Team221 has all the connections provided. Basically it’s a block that attaches the side rails to the ladder bars. You can’t really see it because it’s an internal component. It slides into the aluminum extrusion and has two holes on the sides for bolts to go through.

http://farm8.staticflickr.com/7143/6558453403_1dbcb34c75_b.jpg

Ah, of course. I didn’t realize you had actually used the 221 chassis; I thought that you had just based the drivetrain on the design.

Is the pneumatics for the stuffed bunnies? :confused:

My mistake.