Remarks
dSPACE does not support string parameters in the FMU. The following steps must be done manually after the FMU is generated to set some very important string parameters that are required for a proper execution of Adams-dSPACE real-time Co-Simulation. Failure to set any of these correctly will prevent the simulation from starting. Use a tool/software that has zip/unzip ability to pack/unpack the FMU. Please refer to
https://www.fmi-standard.org for more information.
a. The user must set the correct value for "adams_host" in the modelDescription.xml file inside the FMU generated in the steps above. This is the IP address of the Ubuntu Host in dSPACE Hypervisor where Adams is installed.
b. The user must set the correct value for "thread_affinity_set0" to the CPUs isolated for real-time performance. For example: if Cores 0-3 are isolated, the value of "thread_affinity_set0" should be set to "0-3" in modeDescription.xml.
c. It is recommended to use multiple cores to achieve real-time performance in the simulation. User must set a proper value for "solver_thread_count" integer parameter to achieve this. This should match the number of core isolated for realtime performance. Refer to dSPACE help to set at integer parameter in the FMU from dSPACE ConfigurationDesk. This step can also be done manually.
d. It is important that the user sets correct value for "dspace_vm_fmu_resources_location" string parameter in the FMU. Please refer to the "dSPACE configuration guide for co-simulation with ADAMS" for information on how to configure this.
e. It is important that the user sets correct value for "dspace_rt_fmu_resources_location" string parameter in the FMU. Please refer to the "dSPACE configuration guide for co-simulation with ADAMS" for information on how to configure this.
The resources location in d. and e. are setup using the shared filesystem feature of dSPACE Hypervisor. They refer to the same location under different names for the respective OS(32-Bit RT - Linux and 64-Bit Ubuntu with RT Preempt)
Notes: | ■Running this FMU on a real time platform parent-child simulation, the event will finish once the abortTime, as defined in event file sim_throttle_brake_steerang.xml, is reached. You can prevent this by increasing parameter abortTime="10000" in the .xml event file. ■Selecting the "SCALEXIO" option in Real Time FMI Parent performs a 0.05 seconds initial simulation before the real time simulation. This will allow time for initialization purposes and prevents overruns at the startup of the real time simulation. ■The stepSize parameter defined in the .xml event file "sim_throttle_brake_steerang.xml" (section "dcf:DcfMini") determines the maximum Adams Solver time step of the real time simulation. If the step size in your real time application (that is, the fixed step integrator's step size as determined by HRATIO and the output sampling rate) is set to a larger value than the stepSize parameter in the .xml event file, the Adams Solver time step will be limited to the stepSize parameter in the .xml event file. ■Performing "Adams -to-Adams" co-simulation prior to moving to the real time environment is a good idea to verify the integrity of the model, event, and FMU export process. Steps to do this are not included directly here but can be found in the Appendix: Offline Verification via Adams-Adams Co-Sim. For those interested, go to the Appendix now and perform those steps then proceed with the next section below. ■Did you know? Adams Controls supports heterogeneous FMU export. That is, an FMU exported from an Adams session on one operating system can be used in a co-simulation on another. |