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Unread 07-03-2010, 17:34
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Mike Betts Mike Betts is offline
Electrical Engineer
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Team Role: Engineer
 
Join Date: Dec 2001
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Location: Homosassa, FL
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Re: Charging pneumatics system before match

Quote:
Originally Posted by Chris is me View Post
In said hypothetical robot, would detaching the springs until the robot is placed on field, and then re-attaching them be sufficiently safe?

My robot's being inspected at your events, and I'm not 100% sure if a vented piston will hold the kicker back, since I don't have the robot in front of me.
Chris,

Like you, I do not have the robot in front of me.

From what I have gathered, teams only have seconds to place their robots on the field and many kicker mechanisms have incredibly strong spring implementations. Detaching and reattaching springs may not be feasible for many...

For stored energy systems, it all comes down to the trigger mechanism.

Let's assume that the trigger is a ratchet latch with a piston actuator. If the piston is the only force holding the ratchet latched, I would likely require a positive fail safe be added so that the rachet can not move if the piston is depressurized.

If the ratchet latch is held by a spring and the piston pulls the latch back to fire the kicker, it sounds like it would be OK dependent upon the ratchet, latch & spring being a good solid design.

It's all subjective so I'll end by asking this...

If you took this robot to your local elementary school for a demo, set it up as you will when going onto & off the field or traveling through the pits or going into the size box for inspection, could you walk out of the room secure in the knowledge that none of the inquiring kids will accidentally trip your mechanism and get hurt?

If your honest answer is yes, you will pass my inspection. If you are feeling a bit of a knot in your gut, think seriously about adding a fail safe device...

Regards,

Mike
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Mike Betts

Alumnus, Team 3518, Panthrobots, 2011
Alumnus, Team 177, Bobcat Robotics, 1995 - 2010
LRI, Connecticut Regional, 2007-2010
LRI, WPI Regional, 2009 - 2010
RI, South Florida Regional, 2012 - 2013

As easy as 355/113...