SIMIT Simulation Framework

SIMIT Simulation Framework

With SIMIT you can create, connect and control behavior models using 2D graphical diagrams. In comparison to Simcenter Amesim it is more focused on process industries and PLC programming. This results in a more basic and unspecific component library and with additional functions for e.g. merging Bits to Bytes/DWORDS (or the other way around).

Connecting SIMIT to the Automation Connect tool

Similar to NX MCD, SIMIT can exchange variables using a shared memory connection (SHM), whereas here SIMIT is the Master which creates the SHM. The Automation Connect tool can connect to an existing SHM and will automatically extract the necessary information like variable-names and datatypes.

For this there are two necessary requirements: The Shared Memory-Name and the Mutex-Name need to be explicit, whereby the Mutex-Name needs to be a combination of the shared memory name with the addition Mutex. The default values are SIMITSHM and SIMITSHMMutex. Furthermore, the SHM needs to contain a header containing all variable-information, which can be enabled in SIMIT by checking Signal description in header:

Figure 35: SIMIT enabling signal description in SHM header

To connect the Automation Connect tool to SIMIT you can either have a running SIMIT simulation and simply click Connect - or load, start and connect a new SIMIT project by clicking the Load button and selecting the SIMIT project (see following figure). Note that the latter option is currently only working with SIMIT V8.1.

Figure 36: Connecting to SIMIT

Additional SIMIT specific features

Some additional features are implemented in the Automation Connect tool for SIMIT:

• Automatic loading and /or starting of SIMIT projects: Instead of connecting to an existing SHM, you can select the Load button in the Automation Connect tool to directly start an existing SIMIT project (file ending *.simit). The tool then will perform all necessary steps (e.g. start SIMIT/unload old project, load (new) project, initialize simulation, start simulation, connect to SHM). Note that this feature only works with enabled RCI (see the Settings section below).

• Directly load SIMIT projects: The Automation Connect tool can directly load existing SIMIT projects and extract included Simulation Unit and NX MCD couplings (see the Project section).

• Use existing SIMIT symbol-name-tables: When connecting (coupling) SIMIT with an external system like NX MCD or the Simulation Unit, SIMIT saves the defined variable-names etc. in a file named gateway.config inside the associated subdirectory .\io\ of an SIMIT project. These files can be used by the Automation Connect tool when defining an SHM interface for NX MCD or naming the variables of a Simulation Unit interface.

• Exporting variable-mappings to SIMIT: After connecting all variables in the variable mapper, you can save those as a SIMIT xml file, which than can be imported by SIMIT using the generic import. This will result in creating a new "diagram" in SIMIT containing all defined direct mappings of NX MCD and Simulation Unit variables. If a type-conversion is necessary, this will be modeled using the given SIMIT simulation blocks.

• Time synchronization: SIMIT offers a "Remote Control Interface" for synchronizing with other programs. Using this feature, the Automation Connect tool can synchronize with SIMIT (with SIMIT as a slave) using the "Synchronization Master" (see Time synchronization). Note that this feature only works with RCI enabled (see the Settings section below).

Settings

The Automation Connect SIMIT interface offers following global settings:

Figure 37: Automation Connect SIMIT settings

• Shm Name: This Name is used to connect to the SIMIT Shared Memory. It therefore needs to be identical to the one defined in SIMIT as "Shared Memory-Name". The value can also be directly set in the input box in the SIMIT tab.

• Enable SIMIT RCI: SIMIT Remote Control Interface (RCI) is used for automatized loading and starting of SIMIT as well as synchronization. Because of some issues with certain SIMIT versions, this interface will be accordingly disabled, and needs to be manually enabled again using this option.