pic: Introducing 190's M.O.H. Goat

[Madison]

Originally Posted by Andy Baker

That is one doozy of an arm. I assume that you guys are locking on to the pipe very well in order to keep yourself from swinging. This is very impressive.

Kudos to 190!

Andy B.

Andy, I think that the opposite is true. For the robot to operate optimally, you'd want for it to be free-swinging about the horizontal bar.

You can see that it's tilted away from vertical in that photo, also noting that the arm is at its full extension. Were it to grab a ball and rotate over the top, the rest of the chassis would act as a counterweight, swinging back to vertical and then away to other side, dynamically counteracting the torque exerted by the arm and ball around the horizontal bar.

It's an elegant solution to a reasonably complex problem. It's not the only solution, of course, but I'd say it's the best. It places the center of gravity in a place much lower than the horizontal bar, minimizing the chance for the robot to spin around or otherwise mess up its orientation to the Earth.