Create Entrance and Exit Controls
You can modify the built-in transfer behavior of the material flow objects by programming an Entrance control and an Exit control. The object calls the Method, whose name you entered, as soon as an MU intends to enter or exit the respective object. Be aware that these controls override the standard transfer behavior, meaning that you yourself have to make sure that the MU moves to the correct station!
You can use control methods in a number of ways. You might, for example, count the number of incoming MUs and then, after a specified number has been reached, move the following MUs to a different successor.
You will program the controls in a Method. This can either be:
A Method
object which can be located in a folder in the Class Library or in a Frame. When you want a number of objects, which are located in the same Frame, to call the same Method, you typically use a Method object, which you insert into that Frame. A user-defined attribute of data type method, which only the object to which you added it, can use. When you want all instances of a class to provide the same control, you typically create that control as a user-defined attribute in the class.
To tell Plant Simulation which Method to use, do one of the following. The process is the same for entrance and exit and backward entrance and backward exit controls:
To select a Method in a Frame: Click the button
and select a Method in the dialog Select Object. By default Plant Simulation enters the relative path into the text box. To activate the entrance control of the point-oriented objects before the standard actions are started, when a part enters the object, select Before actions. Standard actions are, for example, starting the processing time or the set-up time, requesting services through the importer, or changing the assembly table of the AssemblyStation.
Select the Method in a Frame, drag it to the text box and drop it there. Here Plant Simulation enters the absolute path into the text box.
To open the dialog of the object, whose name you entered into the text box, either press F2 or right-click the text box and select Open Object.
To create a control method, which belongs to this object: Right-click into the text box and select Create Control on the context menu:
Enter a meaningful name into the text box and select Create Control. Plant Simulation then inserts self.Name_you_entered_for_the_control, such as self.ExitControlEnginePlant.
Select Create Control. Plant Simulation then inserts self.OnBuilt_in_name_of_the_control, such as self.OnEntrance.
Enter the source code of this control into the Method that opens.
Be aware that a control you create with Create Control is a user-defined attribute of the respective object, not a Method object, which you can open in the Frame.
To delete this control, delete the user-defined attribute; deleting the name from the text box just deletes the name, but keeps the user-defined attribute.
Note:The exit control can have an optional parameter of data type object. When the Method has this parameter, then the successor object, which pulls the MU because the MU has contained in the blocking list of the object, will be assigned to this parameter. The MU will be pulled, for example, when the successor becomes available again or when its entrance is opened.
You can:
Compare Transferring Parts from Station to Station
Compare Create Sensors