Thread: Behaviour Of Single Solenoid Pneu. When Robot Disabled Legal ?
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Unread 19-02-2011, 21:37
de_ de_ is offline
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AKA: Dave Edwards
FRC #1310 (Runnymede Robotics)
Team Role: Mentor
  
Join Date: Apr 2005
Rookie Year: 2005
Location: Toronto, Ontario
Posts: 256
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Behaviour Of Single Solenoid Pneu. When Robot Disabled Legal ?
With a 2 solenoid 5 port valve (ex SMC SY3240) , when the robot is disabled, the internal valves will not change state (even though power is off to both valves). The valves only ever change state if power is applied to solenoid that was not last powered.

With a 1 solenoid (spring return) 5 port valve (ex SMC SY3140), when the robot is disabled....

- if the solenoid was currently NOT energized -> the port that is currently pressurized will continue to be pressurized (ie nothing changes)

- if the solenoid WAS currently energized -> it will no longer be, so the internal valve spring will switch the internal valve to the other output port and dump the air in the current port so the pneumatic cylinder will change state.

Is it acceptable from a FIRST rules and safety perspective that when the robot is disabled, the air cylinders move to their "power off" (ie disabled state) (ie move as a result of the disable command). If not, it sure looks like single soleniod valves can't be used in FRC.

Thoughts ?
Last edited by de_ : 19-02-2011 at 21:39.