MATLAB: How to check the units of measure for signals in SIMULINK

measuresignalsimulinkunits

I would like to assign units to Simulink signals and I would like SIMULINK to diagnose"unit mismatch operation" like to pass signals with different units to a SUM block.

Best Answer

The ability to set a "Units of measure" attribute to signals or block inports is not available in Simulink.

You can exploit Simulink Data Objects to explicitly set units to a signal as follows:

s=Simulink.Signal

You can set the field "DocUnits" of the signal "S" as follows:

s.DocUnits='RPM'

However, Simulink will not check the units of this signal when added to another signal.The DocUnits property is only for documentation.

Related Solutions

MATLAB: Can we modify Simulink.Signal properties

You can create your own class that inherits from Simulink.Signal and adds any additional properties/methods you might need.

The following documentation example shows how you can do this.

http://www.mathworks.com/help/simulink/ug/simulink-data-class-extension-using-matlab-class-syntax.html

- Sebastian

MATLAB: What are the Simulink.CustomSignal and Simulink.CustomParameter objects referring to in the documentation for Real-Time Workshop Embedded Coder 4.0 (R14)

In R13, these objects were designed to be used for implementing Custom Storage Classes, but the semantics on this were not very clear. The "custom" objects differed from the normal ones by the initial RTWInfo class that was used to contain code generation data:

custom_object = Simulink.CustomParameter
 custom_object  =
 Simulink.CustomParameter
         RTWInfo: [1x1 Simulink.CustomParameterRTWInfo]
     Description: ''
        DocUnits: ''
           Value: []
custom_object .RTWInfo
 Simulink.CustomParameterRTWInfo
           StorageClass: 'Custom'
                  Alias: ''
       CustomAttributes: [1x1 Simulink.SCAttrib_BitField]
     CustomStorageClass: 'BitField'
normal_object = Simulink.Parameter
 normal_object =
 Simulink.Parameter
         RTWInfo: [1x1 Simulink.RTWInfo]
     Description: ''
        DocUnits: ''
           Value: []
normal_object.RTWInfo
 Simulink.RTWInfo
     StorageClass: 'Auto'
            Alias: ''

However, the Simulink.Parameter's RTWInfo could be overwritten with the required data structure:

normal_object.RTWInfo = thing.RTWInfo
 normal_object =
 Simulink.Parameter
         RTWInfo: [1x1 Simulink.CustomParameterRTWInfo]
     Description: ''
        DocUnits: ''
           Value: []

The Data Class Designer GUI also enforced the use of Simulink.Parameter initialized to a different RTWInfo structure, so it was difficult to do this in the expected way in R13. If your code does not derive from Simulink.CustomSignal or Simulink.CustomParameter objects, you will not need to change to these classes. However, you should be aware that the RTWInfo parameter is now more tightly controlled, so you should move any data which was formally contained in a custom RTWInfo object into the objects derived from Simulink.Signal or Simulink.Parameter.

Best Answer

Related Solutions

MATLAB: Can we modify Simulink.Signal properties

MATLAB: What are the Simulink.CustomSignal and Simulink.CustomParameter objects referring to in the documentation for Real-Time Workshop Embedded Coder 4.0 (R14)

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