At the core of the MES modules, objects are used extensively. Some are based on the ISA-95 standard and others are in addition to the ISA-95 standard. Collectively, we refer to all these objects as MES Objects. An object can represent material, equipment, task, etc. There are some properties, events and methods that are common across all objects. In addition to the common properties, events and methods, there are additional properties, events and methods based on the type of MES Object.
Today, the MES Objects are used exclusively by the Track & Trace Module. In future releases of OEE and other MES product offerings, they too will be based on the MES Objects.
ISA-95 Object Model Inter-Relationships
The MES Objects are divided into four categories, Resource, Definition, Request and Response. These objects are all derived from the AbstractMESObject, inheriting its methods and properties as well as adding their own.
- Resource Objects represent equipment, material or personnel items that are required for production tasks.
- Definition Objects represent the definition of tasks that are carried out during production.
- Request objects represent scheduled production tasks
Response objects represent the actual production results.
There is a MES Object Link object. This is a light-weight object that acts like a reference to the full MES object, but only contains some general information. Consider using this when populating dropdowns or lists to reduce unneeded overhead.
Both the AbstractMESObject and the MES Object Link objects have a getMESObjectType() function that returns the type of an MES object. The MESObjectTypes object has the following helpful functions when working with MES Objects (T&T).
ISA-95 does not define object functions (or methods), but the MES modules extend these objects with functions to make common tasks easier. There are common functions that are available on all MES objects and then each MES object type may have additional functions. The additional functions are appropriate for the type of MES object.
An example of an object function that is common across all MES object is addCustomProperty(). An example of a object function that is specific for one type of MES object is setMaterial(). The setMaterial() function is only appropriate for a response segment type of MES object.
The Object model diagram in the Object Types section provides a quick view on which functions each object provides and which functions are inherited. Detailed information regarding the functions themselves can be found under the specific object in the Object Types section.