Representing Concurrent Actions and Solving Conflicts

Situation calculus for controller synthesis in manufacturing systems with first-order state representation

“…For example, DRILL(part, dmtr, speed, x, y, z) represents the action of drilling a hole of a certain diameter, at a certain spindle speed, in a specific position of a given part. In the manufacturing domain, we are concerned with operations that may occur simultaneously [23,27,28,29], hence we adopt the concurrent, nontemporal variant of the Situation Calculus, where a concurrent or compound action a is a possibly infinite set of simple actions, like the one above, that execute simultaneously [23,Chapter 7]. For example, {ROTATE(part, speed), SPRAY(part, subst)} represents the joint execution of rotating a part at a given speed while spraying it with some substance.…”