Adams Advanced Package > Adams Controls > Functional Mock-up Interface (FMI) > Options in the msc_adams_realtime parameter

Options in the msc_adams_realtime parameter

An Adams FMU msc_adams_realtime parameter can be used to configure and tune the real time simulation. You may modify some integration parameters of the Adams FMU. Instead of using the FMU parameter msc_adams_realtime, you may also set the environment variable MSC_ADAMS_REAL_TIME. Using the environment variable is particularly important for the case of real-time systems that do not support string FMU parameters. The syntax of the environment variable is the same as that of the Adams FMU parameter.
The value of this parameter is a string of keywords and/or keywords and values separated by slashes. For example:
ON/MESSAGESON/FIXIT/2/GSTIFF
Notice in this example the keyword FIXIT is followed by an integer value. The value string is processed from left to right, hence a keyword on the right may cancel the effect of a keyword on the left. The following table provides descriptions and examples for all supported keywords. Except keyword ON, all other keywords are optional. Keywords are case sensitive.
 
Keyword
Description
ON
Required value to turn on the real time environment. This keyword turns off messages once the real time simulation begins, turns off results generation, and adjusts internal flags for optimal performance.
OFF
Option OFF can be used to cancel all real time options without the need to erase the values.
For example:
ON/MESSAGESON/OFF
The above will cancel the real time mode.
MESSAGESON
By default, the Adams FMU will always generate a partial message file. The partial message file includes all information up to the start of the real time simulation. By default, no messages are appended during the real time simulation. Once the real time simulation ends, a brief report is appended. However, to generate a complete message file, add MESSAGESON to the parameter:
For example:
ON/MESSAGESON
Using this option, a complete message file is generated.
MESSAGESOFF
Turns off a previous MESSAGESON keyword. Using this option, the Adams FMU will generate a partial message file.
For example:
ON/MESSAGESON/HHT/MESSAGESOFF
A partial message file will be generated for this example.
RESULTSON
This option can be used to generate results files (*.res). Notice that using this option the Adams FMU might take a much longer time to complete a simulation step.
For example:
ON/MESSAGESON/RESULTSON
These options will generate complete message files and full results files.
RESULTSOFF
Turns off a previous RESULTSON keyword.
For example:
ON/RESULTSON/MESSAGESON/RESULTSOFF
NOEP
Use this option to run a real time simulation without using the Extended Parallelization option. See Running with Extended Parallelization.
For example:
ON/MESSAGESON/NOEP
This option will cancel the use of the Extended Parallelization algorithm
LUNOSINGULAR
By default, when the real time mode is on, singularities in the numerical factorization of the Jacobian matrix are ignored. Setting option LUNOSINGULAR forces the Adams FMU not to ignore the singularities. If a singularity is found, Adams Solver will handle it causing several overruns.
For example:
ON/LUNOSINGULAR
EULER/dvalue
By default, the Adams FMU uses 0.1 radians as a threshold to trigger a Euler singularity and start the process to reformulate the equations, causing a delay and the corresponding frame misses.
For example:
ON/EULER/0.05
may help to avoid a Euler singularity during the simulation. The value after the keyword is an angle in radians.
FRAME/dvalue
This option is required only if running the Adams FMU using an FMU Compliance Checker. The keyword must be followed by a real number in seconds.
For example:
ON/FRAME/0.001/MESSAGESON
Here, a frame of 0.001 seconds is specified.
FIXIT/ivalue
Use this option to change the INTEGRATOR setting in the data set files (*.adm). There is no need to re-generate the Adams FMU. Set option FIXIT followed by an integer value to change the setting.
For example:
ON/FIXIT/2
Here we specify two iterations to be used.
WFIXIT/ivalue
By default, only during the initialization phase, the Adams FMU will use 5 iterations to accurately initialize the simulation. Use this keyword in case you find you need more iterations during the initialization phase.
For example:
ON/WFIXIT/7
HRATIO/ivalue
Use this option followed by an integer value to modify the HRATIO setting in the Adams FMU. There is no need to re-generate the Adams FMU.
For example:
ON/HRATIO/2
HMAX/dvalue
Use this option followed by a value in seconds to modify the HMAX setting in the Adams FMU. Sometimes it may happen that an Adams FMU is properly exported with the INTEGRATOR's HMAX option set to a particular frame size. However, when trying to run the FMU using larger frame sizes, the FMU may not take larger steps. Use this option to modify HMAX if need be.
For example:
ON/HMAX/0.002
GSTIFF
Use this option to change the INTEGRATOR setting in the Adams FMU. There is no need to regenerate the Adams FMU.
For example:
ON/MESSAGESON/FIXIT/2/GSTIFF
Here we force the Adams FMU to use the GSTIFF integrator.
HHT
Use this option to change the INTEGRATOR setting in the Adams FMU. There is no need to regenerate the Adams FMU.
For example:
ON/MESSAGESON/HHT
Here we force the Adams FMU to use the HHT integrator.
LSS/dvalue
Use this option to set the LSOLVER/STABILITY value. There is no need to regenerate the Adams FMU.
For example:
ON/HHT/LSS/0.03/FIXIT/2
The provided value must be bigger than zero and less than 1.0.
EPRINT
Use this option to generate EPRINT information. This option is useful when debugging an Adams FMU.
For example:
ON/EPRINT
 
Note:  
The values of the string parameter msc_adams_realtime are the same for the environment variable MSC_ADAMS_REAL_TIME.