Hi,
There are 2 things:
A) We want to connect 4 encoders to the RC this year and we wanted to know if it is legal and possible to do so, and if we can use the encoders from BaneBot (http://www.banebots.com/p/EN-G0561-KT). If we can, than how can we connect them (to where?) and how can we get each one to function without colliding one with the other?
B) Can someone direct us to how to program 4 mecanum wheels (http://andymark.biz/am-0083.html).
Thanks, Tal
Neat-Team #1943
Hope your Andymark mecanums are arriving quicker than ours… we’ve been waiting over a week now. It seems like they are proving more popular than expected, and I know Andy is doing everything he can to get them shipped.
In the meanwhile, yes… you can use four encoders, and there are some excellent resources on programming mecanums… you may wish to also search for the web and CD forums for “meccanum” and “mechanum” when you do your searches, you will find different results for each search term.
There are some good resources in the CD white papers… one is called “strafing”, http://www.chiefdelphi.com/media/papers/1836, and there are also some notes at http://www.usfirst.org/community/frc/content.aspx?id=1112 (which also has some other great presentations, too.)
As for the encoders, banebots sells a board that takes care of determining direction and also divides the data rate so that the encoders will be much easier to read.
If you search the CD forums, white papers and web you will find much more information, but hopefully this will point you to a couple of good starting points. Eventually, however, you will need to synthesize all this information to create your own control code. Make sure you let the build team give you plenty of practice time with a rolling chassis to get it working, and then for the drivers to get used to the unique opportunities presented by omni-directional drive.
Jason
If the cost of the encoders from Banebots is less than $400, you can use them. You should read the rules over closely on COTS items.
As for using 4 encoders together, take a look at Kevin Watsons Encoder FAQ and sample code. It can work with up to 6 encoders. Of course you’ll need to modify or customize it to meet your needs.
http://www.kevin.org/frc/encoder/
http://www.kevin.org/frc/frc_encoder.zip
Thanks, I will check it.
if you need code for the mecanum drive, check out this code written by artdutra04. I used this concept on a vex mecanum robot and it worked perfectly (kudos to artdutra for making the code, it is really useful)
good luck, mecanum drivetrains are really fun! 