We have noticed a gripper timing error on the pick. On some occasions we noticed that the gripper was signalled to close after the pick dwell instead of before it.
We use a TriggEquip statement in Rapid with a distance specified as 1 (originally we used 0 & had problems with VacAct set > 0.06). The VacAct time currently in pickmaster is around 0.05 - 0.06.
We have tried changing many of the relevant pickmaster variables but the only thing that seems to give the correct result is to change the 1mm distance in Rapid to say 10.
We have increased the pick time to 0.6s so that the problem can be seen without a camera.
The difficulty is that it is not consistent. ie I cannot always reproduce the problem.
We are thinking it may explain some poor pick situations we have seen in production situations.
The behaviour that you described is explained in the PickMaster releas notes:
"2.12 - Vacuum event accuracy ----------------------------- The accuracy of the vacuum events (Vacuum Activation/Reversion/Off) is described in the limitations section for the TriggEquip instruction, in the RAPID reference manual.
The values typed in the PickMaster dialogs are used as EquipLag in the TriggEquip instruction. Act and Rev times are positive and the Off time is negative."
The VacAct set is OK up to 60 ms after that there might be some timing issues according to the RAPID manual (so this behaviour is by design and not a bug)
Your workaround to set the Triggequip distance will probably work. But if you set down the robot speed you might see some changes in the activation positions.
Yes we had picked up on the limitation of the VacAct setting a while ago, and we had set the Triggequip distance to overcome this. The problem appears to be as I said, that setting a distance of 1 (in combination with a VacAct<0.6) appears to result sometimes in the gripper being triggered at the end of the pick time (dwell) instead of just before the start of it. Setting a value of 10 (again in combination with a VacAct <0.6) appears to give a consistent trigger just before the start of the pick time (dwell)
Sorry for the delay we have looked at your reply and we believe that this is a robot related issue. Unless this is not resolved already I would like you to contact Serop Product Support (serop.product_support@se.abb.com) for additional help.