I am facing a problem with a Fanuc robot old robot model( R2000i 165F RJ3i controller) on a line tracking application.
There are 76 Moulds(variants) on moving conveyor(130mm/sec) and the Robot should pour the chemical on these moulds.
I wrote 76 tracking program in 76 PNS that will be called by PLC when it reads the RFID tag for each mould.
while tracking in auto cycle robot is giving an offset of 150mm from the taught position, if I run the program directly (without PNS) it is working correctly and accurate.
for part detect trigger am using a limit switch, the RFID tag reader and limit switch are fixed close (100mm)so when PNS starts the robot will start tracking(robot is not waiting much time for trigger) then the offset is happening and if I increase the distance between RFID and limit switch it is working accurately(that I cant do because the distance between two adjacent moulds are less so robot will not able to track within the boundary.)
how can I solve this issue?
LINE TRACKING
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Mr.Robot -
May 13, 2018 at 9:05 PM -
Thread is marked as Resolved.
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Are you saying that there is a 100 mm space between the rfid reader and limit switch? What is the distance between two adjacent moulds? Could you replace the limit switch with a trough beam or photo eye. that would allow placement and fixture nearly anywhere.
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Use the rfid reader to tell the plc to call the job, You can add in your robot code a wait statement looking for the limit switch to activate your tracking program.
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The distance between two adjacent moulds are 650mm since conveyor speed is 130mm/sec so Robot hardly get 5sec to do the task,
they already have three other running lines with the same setup, So changing the part trigger to a photoeye is not an option for me.
I compared tracking setup and program with neighbouring lines and there is no difference at all.please check this attachment so you will get an idea how it is.
thank you
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Sounds like you will have to separate the trigger into a separate task, or into a background task. In that task you would remember the count when the trigger switch was hit, then use that count in your PNS program when you start your tracking.
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Okay, ill give that a try.
Is there anything like that we have to consider some delay time before it runs the program when PNS is started?