Is there a way to link plots to simscape log data / simscape results explorer data?

When you enable data logging for simscape, you can browse all simulation data using the simscape results explorer.

After selecting sveral data nodes, it is possible to "extract current plot into new figure window". I would like to customize my figure and link it to the simulation data but cannot figure out how.

Simlog won't show up as data source and there is also no auto-linking in the data source dialogue.

Any idea or help?

Answer 1

[Yifeng Tang]

You may access everything in simlog through MATLAB base workspace. This documentation page includes some basic functions to access and plot the logged data: https://www.mathworks.com/help/physmod/simscape/ug/log-and-plot-simulation-data.html

To take it one step further, you can extract the time and value (in any reasonable unit you wish) of a simlog signal series, and use them as base workspace variables. Then you can "hold on" and plot several of them together.

Here is the doc page on the "series" of simlog data: https://www.mathworks.com/help/physmod/simscape/ref/simscape.logging.series.html

The "time" and "values" functions/methods of the series will give you the access you need.

Some pseudo-code:

% run some simulation first
t  = time(simlog.motor.w.series);  % all signal should have the same time stamps
v1 = values(simlog.motor.w.series,'rpm');  % specify unit
v2 = values(simlog.motor.v.series);  % default unit
figure(1); clf;
hold on;
plot(t,v1);
plot(t,v2);

I believe you can also do

t  = simlog.motor.w.series.time;
v1 = simlog.motor.w.series.values('rpm')

Answer 2

[Yifeng Tang]

You may access everything in simlog through MATLAB base workspace. Follow the instructions on the following documentation page and you will be able to use commands like "plot" and all of its options to customize your figures. You probably will end up with a post-process script once you figure out what you want to plot.

https://www.mathworks.com/help/physmod/simscape/ug/log-and-plot-simulation-data.html

[Andreas]

Thanks for your answer - nevertheless I am facing the following problems:

• multiple plots are not possible using commands like

plot(out.simlog.Befeuchtungsregelung.kg)

ans = 

  struct with fields:

          id: [1×1 Figure]
    childIds: []

>> hold on
>> plot(out.simlog.Befeuchtungsregelung1.kg)

• --> hold on does not work. Each plot command creates a new plot / figure
• creating a dummy plot and replacing the data with links to simlog does not work either
• 
• 1. Schicht in reality looks like:
• 

[Yifeng Tang]

You can extract the time and value (in any reasonable unit you wish) of a simlog signal series, and use them as base workspace variables. Then you can "hold on" and plot several of them together.

Here is the doc page on the "series" of simlog data: https://www.mathworks.com/help/physmod/simscape/ref/simscape.logging.series.html

The "time" and "values" functions/methods of the series will give you the access you need.

Some pseudo-code:

% run some simulation first
t  = time(simlog.motor.w.series);  % all signal should have the same time stamps
v1 = values(simlog.motor.w.series,'rpm');  % specify unit
v2 = values(simlog.motor.v.series);  % default unit
figure(1); clf;
hold on;
plot(t,v1);
plot(t,v2);

I believe you can also do

t  = simlog.motor.w.series.time;
v1 = simlog.motor.w.series.values('rpm')

[Andreas]

@Yifeng Tang Thanks alot - can you post your idea as answer? I will mark it as accepted answer then.

I directly put out.simlog.Befeuchtungsregelung9.kg.series.time & out.simlog.Befeuchtungsregelung9.kg.series.values in the data source field and now it works.

But the process is a real pain.

• data source window not properly resizeable
• clicking a field deletes its input
• there is no known way to automate linking ("linkdata on" only enables linking, but no autolinking)

[Yifeng Tang]

done. thanks for the suggestion.

[Yifeng Tang]

@Andreas Once you know what you want to plot, it's usually easy to write a MATLAB script to access and plot a set of data, with (nearly) unlimited control of how the figure should appear. If you wish for the figure to update automatically after each run, you may put the script name in the Callback function after the simulation is finished (StopFcn). Every time a simulation is finished, the script will be executed and your plot should be updated (or generate a new one, if you like).

Here you can find more info on Model Callbacks: https://www.mathworks.com/help/simulink/ug/model-callbacks.html#btoznm0

[Andreas]

@Yifeng Tang I am more of a wysiwyg-guy and try to customize figures with the figure toolbox (I am bad at scripting) ;-)

The data link solution works fine for me, hence the created figure can be used for a series of models all with the same block name scheme.