Quote:
Originally Posted by Qbranch
How does your guys' gripper function exactly? I've watched the videos on your site, but it's still kind of far away.
Thanks,
-q
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Here's a picture of the bot for reference:
http://uberbots.org/2008/media.php?m=658
Here's a top view of the gripper (it's folded in):
http://uberbots.org/2008/media.php?m=678
Here's a side view with the ball:
http://uberbots.org/2008/media.php?m=658
This is kind of complicated to explain without having the robot here to point to etc, so I'm sorry if it sounds convoluted:
We have an arm with four aluminum "fingers" coming out of it. Coming down perpendicular to the arm is a stationary tube with a pneumatic cylinder inside. From each finger there is a fiberglass driveway reflector coming out at an angle. This makes them want to stick out at an angle. However, we have a stationary cord that connects all of them together, pulling them towards each other. At each end of this cord, there is more cord that goes up into the stationary tube where they are connected to the cylinder. This completes the rounded shape of the reflectors. By using the cylinder, we can adjust the length of the cord to be longer or shorter- this makes the radius of the gripper larger or smaller. To pick up the ball, we open the gripper, place it over the ball, and then close it around it. The red thing is a piece of fabric which has elastic such that it is taut when it is holding a ball, but not floppy otherwise. It helps to maintain ball control, and in the event of the fiberglass snapping (which it hasn't yet in competition), it will hold it in and prevent entanglement/violation of the 80" rule.