|The Resource Simulation command's basic functions (e.g., the VCR-like buttons) function identically to those of Process Simulation . However, the purpose of Resource Simulation differs from that of Process Simulation , and this page describes those differences.|
|There are two different ways to use Resource
Although this command is not intended to simulate individual activities under a resource behavior, you can run the command by selecting an individual activity first, also. In that case, Resource Simulation tries to find the closest ancestor of the preselected activity that:
If no ancestor can be found to match this criteria, the root resource is simulated.
|Starting with the root resource within the PPR tree's
resource list, all the behaviors of the resources, and their child
resources are included in the simulation. The behaviors of
different resources are not linked with timing constraints However, the
physical activity of a resource behavior (known as a Task Specification
Activity or TSA) may have links
underneath the resource behaviors. Possible links are:
These are taken into account during the simulation. The TSAs belonging to the same behavior are linked through control flow links. Also, the starting time sets for different TSAs are obeyed by the simulation, as long as the sets do not conflict with other time constraints defined for the given TSA.
In the absence of such links, all behaviors run in parallel, even if the behaviors are across multiple levels in the resource hierarchy.
When the TSAs under different behaviors are linked with precedence constrains or synchronization constraints, this determines the sequence of execution across behaviors. For example, suppose there are two stations: Station 1, and Station 2, and their child resource behaviors, Station1Behavior, and Station2Behavior. Each station behavior includes a load and unload activity. If there is a precedence constraint between Unload1 (under Station1Behavior) and Load2 (under Station2Behavior), it is honored during the simulation, and therefore Station1Behavior and Station2Behavior do not run in parallel.
|If a robot/physical resource appears in the resource hierarchy, but is not assigned to any TSAs, then its tasks are not simulated as part of simulating its parent resource behavior.|
|If a TSA has a robot task assigned to it, then the simulation simulates the active robot task for that assignment and ignores any child activities of the TSA itself. This is consistent with and identical to how simulation treats robot tasks assigned to process activities in the process tree.|
|When a logical resource is pre-selected, the logical resource’s behavior and/or its child behaviors are simulated (if resource behavior is absent then only child behaviors are simulated). However, the whole resource world as described in the previous section is included behind the scenes. This is for the purpose of updating the world to the state at which it would be at the beginning of the selected resource’s behavior/process. This is referred to as simulating the selected resource in the context of the whole resource hierarchy.|
|If activities have precedence constraints, the precedence constraints are observable in the simulation.|
3D States or Initial Conditions
|If 3D states or initial conditions are defined on individual TSAs, they are applied by the simulation engine at the beginning or end of the TSA itself|