You can use the MOVE/EXCLUSIVE_ZONE command.
The advantage of using this method is that PC-DMIS only makes one of the arms wait if the other arm is in its zone.
The disadvantage is that you need to put MOVE/EXCLUSIVE_ZONE commands around all the blocks of commands that command an arm into the overlapped area in the middle of the dual arm volume.
To use this command:
Find the sequence of commands that causes one of the arms to enter into an overlapped portion of the CMM volume.
Place a MOVE/EXCLUSIVE_ZONE=ON command at the start of the sequence.
Place a MOVE/EXCLUSIVE_ZONE=OFF at the end of the sequence.
The MOVE/EXCLUSIVE_ZONE=ON is used to specify two corner points that form a 3D zone. This zone is reserved for the arm that is assigned the command. If the other arm is already in the requested zone, then PC-DMIS waits until the first arm is out of the way and exits the contested space with a MOVE/EXCLUSIVE_ZONE=OFF command. See "Inserting an Exclusion Zone Command" in the "Inserting Move Commands" chapter for additional information.