# FMU

FMU (Functional Mock-up Unit) is an abstract modeling element that defines a generic modeling element in MotionSolve.

Fmu

## Description

A standard, tool-independent interface, the Functional Mock-up Interface (FMI) defines the interface for accessing and depositing data into the FMU. It support models using a combination of XML files and compiled C-code.

MotionSolve uses the FMI to import one or more FMUs into a system model, connecting these to other modeling components and generating the combined model for a solution.

See the Comments section of Control: FMU

## Attribute Summary

Name Property Modifiable by command? Designable?
id Int () No No
label Str ()
type Enum ()
path FileName ()
x Reference (Array)
y Reference (Array)
u Reference (Array)
ic Reference (Array)
static_hold Bool ()
dll FileName
interval Double ()
var_name Str ()
var_ic Double ()

## Usage

Fmu(
path    = "mefmu_siso_cs.fmu",
type    = "CS",
x       = array_x,
y       = array_y,
u       = array_u,
)

## Attributes

id
Integer
Element identification number. This number is unique among all FMUs.
label
String
The “short” name for the FMU element.
type
String
Type of FMU. Choose between “CS” (CoSimulation) or “ME” (ModelExchange)
• Default: “ME
path
FileName
The path to the FMU file.
x
Reference(Array)
Specifies the Reference_Array used to store the continuous states, x, of this FMU.
You can use the ARYVAL() function with its ID to access the states in a MotionSolve expression. You can also use its ID in SYSFNC and SYSARY to access the states from a user subroutine.
y
Reference(Array)
Specifies the Reference_Array used to store the output, y, of this FMU.
You can use the ARYVAL() function with its ID to access the outputs in a MotionSolve expression. You can also use its ID in SYSFNC and SYSARY to access the outputs from a user subroutine.
u
Reference(Array)
Specifies the Reference_Array used to store the input u of this FMU.
You can use the ARYVAL() function with this ID to access the inputs in a MotionSolve expression. You can also use this ID in SYSFNC and SYSARY to access the inputs from a user subroutine.
ic
Reference(Array)
Specifies the Reference_Array used to store the initial conditions for the continuous states of this FMU.
You can use the ARYVAL() function with its ID to access the ICs in a MotionSolve expression. You can also use its ID in SYSFNC and SYSARY to access the IC values from a user subroutine.
static_hold
Boolean
A flag for indicating whether the value of dynamic state is kept constant during static or quasi-static simulations. It is only applicable to Model-Exchange FMUs.
See Comment 8 of the Control: FMU for more details.
dll
String
Specifies the path and name of the DLL or shared library that will be used to load the user’s FMU. MotionSolve uses this information to load the user subroutine in the DLL at run time.
• Default: “nugsefmu”
interval
Double
The time interval between successive communications with the FMU. FMU outputs are interpolated for all other calls.
• Default: HMAX, the maximum step size defined for the simulation by the simulation control parameters
String
IP address for the FMU connecting to MotionSolve.
• Default: “PIPE”
A pipe is used as the means for inter-process communication when MotionSolve and the FMU reside on the same machine. When MotionSolve and the FMU reside on different machines, specify the actual IP address as a string.
var_name
String
String that lists the name of each variable inside FMU that can be assigned a value.
• Values delimited by “;” (semicolon)
• Default: “”
var_ic
String
String that lists the value for each variable defined by “var_name” that needs to be set by the user.
• Values delimited by “;” (semicolon)
• Default: “”

## Example

x = Array(label="States", type="x")
y = Array(label="Outputs", type="y")
u = Array(label="Inputs", type="u", size=1)
u. variables = Variable(
label    = "u[0]",
function = "-wz(30102010)+varval(30100100)"
)
fmu = Fmu(
path       = "Hydraulic_Valve.fmu",
type       = "ME",
x          = x,
y          = y,
u          = u,
ip_address = "PIPE")