programming emergency stop 3

[troy06]

I have a Fanuc 200iB that uses an RJ3iB controller. I have done some basic programming to learn how to use the robot but now I need to write a production program.I have a sensor that indicates if the door is opened or closed. I want to make the program such that if the door is opened during cyle,the robot stops,much like an emergency stop button.Any information would be appreciated as I am very new to programming.

 

[nornrich]

troy06,

My first word of advice is if you are going to make the door a part of a safety circuit, then don't do it in software. Series this switch with a Master Control Relay (MCR) specifically designed for E-stop situation. This MCR should shut off all power to the robot that could cause damage. Within your program you can have a reset button that will reset the operations after the MCR is active (i.e. all safety conditions are satisfied).

Regard,

Rich....

Richard Nornhold, PE

http://www.ovenind.com

 

[tygerdawg]

I would expect your controller to have dedicated I/O points for ESTOP circuits. ESTOPs are harsh and should be used sparingly. You can expand the ESTOP circuit by using modern safety relays that will open if any part of the circuit is open, then requires operator reset signals. The controller may even have dedicated I/O points for door circuits. Usually if that circuit gets opened (say, by a manual switch), then the arm decelerates to a stop, then applies brakes, then de-energizes the arm in an orderly manner. Sometimes even including the point at which you stopped so you can move the arm, then go back to that retained point. Then the solenoid-latched door lock is opened to allow entry to the workspace.

TygerDawg
Blue Technik LLC
Virtuoso Robotics Engineering

http://www.bluetechnik.com

 

[BrianPetersen]

On that controller, there is indeed dedicated (and dual-channel) I/O for "emergency stop in" (this is the dual-channel input from external emergency-stop devices), "emergency stop out" (this is the status of the robot system's own E-stops on the teach pendant and the controller panel), "auto stop" (disables automatic-run but allows operation with the teach pendant), and "servo off" (disables servo motors no matter what).

What you need is a dual-channel circuit from the robot controller "auto stop" to the safety switch, which has to be a safety-rated dual-channel device. It will do exactly what you are looking for without any programming necessary. The E-stop system also should not require any robot programming.

If you are in the USA, look up ANSI/RIA R15.06-1999 and if you are in Canada, look up CSA Z434-03 - these standards cover robot installations. The nuts-and-bolts of your particular robot interconnections are in the manual.

 

[bespokemachines]

All emergency stops and guard switches ahould stop the machine if the emergency stop circuit is broken. Therefore the easiest way is to break the wire that goes through one of your existing emergency stops with your door switch.

I make special purpose machines an I do this all the time without any problems.

 

[eseq]

When considering the design of any machine it is important to eliminate as
many hazards as possible and by doing so negating the need for any
additional safety measures. However, most machines are not as simple as
that and there will undoubtedly be hazards that cannot be eliminated. For
hazards that cannot be reasonably removed or limited by design, protective
guards (or similar safeguards) are required. These guards may be reinforced
by interlocking devices, direct mechanical guard locking and/or control system
linked, to affirm the guard’s integrity. The design of the control system should
be such that proximity to the hazard is restricted, typically by requiring two
hand control or perimeter monitoring (light curtains etc.). Where the
operational requirements of the machine leave hazards exposed or to
reinforce other safeguards, then display notices in the form of text, words,
signal, symbols, diagrams, etc., and, importantly, training and instructions.

Andy
www.automationengineering.co.uk