Hi,
I would need a lot more information to recommend something. Are these machines close enough together that the robot arm can reach both without having to move? If this is not the case then there are several URplus 3rd party kits for putting our arms on an external 7th axis. I’ve provided a link to the UR+ portal where you can take a look. These kits are typically in the $20k-$30k range though. I would recommend talking to your distributor though too. UR+ Products | Automate Faster
Both machines can be accessed from a central location
My question is more related to how do I manage signals from two machines via digital .io into the robot
How will the robot know which machine to service first etc
I think you have to look at the number of handshaking signals required to effect a clean design and see if the robot has enough IO to do this. If the robot does not have enough DI/DO’s to handle all the handshaking then you might need to add a PLC and make the PLC that arbiter of the machines as they request service from the robot to load/unload open/close doors, etc.
The robot program structure would be a thread that manages all the communication to the machines or PLC (assuming it’s via DIO) and this thread would translate this digital handshaking into ‘‘states’’ that a main program would respond to. So the main program would behave as a state machine using switch-case constructs. An example of the states would be :
ServeMachineA
ServeMachineB
OpenDoorMachineA
OpenDoorMachineB
UnloadPartMachineA
etc
This is the more elegant approach. There are other approaches like just using IF-ELSE logic etc.