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Unread 11-02-2012, 03:07
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VEX Robotics Engineer
AKA: Arthur Dutra IV; NERD #18
FRC #0148 (Robowranglers)
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Re: Ideas to get onto ramp??

Quote:
Originally Posted by LiquidMagik View Post
http://i.imgur.com/hYGkF.png

I found the golden ratio.
If you are indeed using a pneumatic cylinder to drive that linkage as shown in this diagram, you will probably find this linkage geometry will not work the way you intend. Right now the pneumatic cylinder and linkage pivot points pass the linkage's kinematic singularity point* during some point in the middle of its intended transition. This means that the linkage can toggle between either its intended geometry of rotating out and down or trying to rotate into itself/the robot.

* This occurs when all three pivot points in this linkage (the pneumatic cylinder pivot, the cylinder clevis pivot, and the linkage arm pivot) line up in a straight line. At this point, it both takes an infinite amount of force to move the linkage (without external stimuli) and has an indeterminate outcome about which toggle position the linkage will be in.
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Art Dutra IV
Robotics Engineer, VEX Robotics, Inc., a subsidiary of Innovation First International (IFI)
Robowranglers Team 148 | GUS Robotics Team 228 (Alumni) | Rho Beta Epsilon (Alumni) | @arthurdutra

世上无难事,只怕有心人.