pic: Off Season CAD Practice

[GeeTwo]

I was wondering a bit that you were a rookie and 2011, but are still a student. I guess by that you do not mean an FRC rookie, or are you on a team where you can play as a student six years?

I won't add any more to the "roller claw" discussion, as you claimed "basic tools and COTS parts" in the OP, and most if not all of what I would have said has been covered, anyway.

Most importantly, as far as "modern 2013+ rules" ar e concerned: 2015 had no lateral "sprawl" rules beyond fitting on your alliance's half of the field, but In 2012-2014, the robot was required to start the game completely within the "frame perimeter", with a maximum height restriction. This arm does not seem to meet this requirement; you can't get it to fit both requirements at the same time. The obvious answer is to have another articulated joint or two. I think there is an alternative, though I haven't run the numbers: make the mobile segment of arm a bit shorter, and mount the claw on the opposite side of that arm. Give it a mobility of about 350 degrees rather than 170 degrees (doesn't seem to be a problem from what I can see). Then, you could start with the arm stowed on what is currently the "front" side, pick up logo pieces off the floor from what is currently the "back" side, and score them high on the "back" side with less rotation issue than you would have with what you designed. If I recall the 2011 game correctly (I did not play it, but skimmed the rules a few months ago), this would probably also reduce the number of times you would have to turn the robot around.

Finally, I find that motor sticking out the side of the "wrist" to be cringe-inducing. This would be a great place to have the "thumb" actuator respond to a "muscle" pull along the arm. This could be done via pneumatics, a lead screw (or even threaded rod and a coupling nut), or a light chain or belt. Especially if you use pneumatics, consider actuating both jaws of the claw; this would allow you to "rotate" pieces for more solid placement.