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Unread 12-02-2013, 11:36
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FRC #0997 (CHS Robotics)
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Re: Can you help us get our robot unstuck?

Quote:
Originally Posted by Tem1514 Mentor View Post
I love the design of flipping end over end and will to try and suggest a possible answer that may or may not work is, using the video as a reference.

It may be possible to rotate the robot frame CW around the upper arm and at the same time rotate the lower arm CCW. This will have to done with great care so that as the load is changed from the lower to upper arm you robot doesn't just lose it's grip and fall off

Aside the 54 " possible problem you need to watch out for differences in height from one rung to the next which according to rules may be up to 1/4 inch but I would allow for at least 3 inches either way.
Yes, I agree that this is what probably needs to be done, but if you study the contact points you will see that it may not currently be possible. Trying to rotate the robot frame CW around the upper arm will tend to push the robot frame down. And trying to rotate the lower arm CCW will tend to push the robot frame up. Both are not possible at the same time, and I think this is what ends up jamming the robot in place when it tries to change grips.

The design may need either an additional joint in one of the arms, or some ability to slide one of the pivot points a bit to allow this transfer to proceed smoothly. As it is, there may not be enough degrees of freedom in the system to allow the correct motion that can transfer the weight properly.
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