Generate random instance of all uncertain atoms present in all USS System blocks of Simulink model

    Note   usimsamp will be removed in a future release. Use usample instead.


sample = usimsamp(ModelName)
sample = usimsamp(ModelName,BW)


The command usimsamp samples a Simulink® model. Note that if the model contains any USS System blocks, then the model can be interpreted as an uncertain Simulink model. The sample generated by usimsamp is a scalar structure, with fieldnames corresponding to the uncertain atoms within all of the USS System blocks, and the values are specific random samples of the atoms.

For ultidyn atoms, the magnitude of the sampled poles can be limited using an optional second bandwidth argument, BW. See usample for more information on this parameter.


See Robustness Analysis in Simulink for a more detailed example of how to use usimsamp.

Open the model file associated with the example.


This has 3 USS System blocks. They are plant with a ureal atom named unc_pole; input_unc which is a ultidyn object, and sensor_gain which is a ureal atom.

Run usimsamp on the model, yielding a structure as described above.

unc_pole = ureal('unc_pole',-5,'Range',[-10 -4]); 
plant = ss(unc_pole,5,1,1); 
input_unc = ultidyn('input_unc',[1 1]); 
wt = makeweight(0.25,130,2.5); 
sensor_gain = ureal('sensor_gain',1,'Range',[0.1 2]); 
data = usimsamp('usim_model') 
data = 
      input_unc: [1x1 ss] 
    sensor_gain: 0.9935 
       unc_pole: -4.1308 
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