What's the fastest way to send out data from Simulink during simulation?

Hello everyone, I'm looking for the fastest way to send out Simulink data to Python during simulation. As a way of sampling the simulation in a "real time" manner.

I've tried MQTT publishing with Industrial Communication Toolbox but the delay is 0.5s on average (which is too much for my application, RL training). Also running the get_param command from Python takes about 0.3s.

Is there a way to obtain a signal's data "on the go" with minimal delay from Simulink to Python? Even if data is lost from time to time. I'm interested in speed more than security level.

Thank you!

Answer 1

[Vijay]

Hello @Enzo Yacometti

Data is passed by value from MATLAB to python so, if your data is large, it will take time. However, you mentioned you need to sample a signal from SIMULINK.

You can do the following

1. Write the instantaneous value of signal in a workspace variable using toworkspace block.
2. Using matlabengine api from python read that variable.

Sample code:

Import matlab.engine 
eng = matlab.engine.connect_matlab(); 
while True 
    Val = eng.workspace[‘instantaneousSinglaValue’]; 
    #do soemthing with val 

Use the link for further information

1. Log data to workspace from Simulink model - Simulink - MathWorks India

2. Connect shared MATLAB session to MATLAB Engine for Python - MATLAB matlab.engine.connect_matlab - MathWorks India

Hope that helps!

[Enzo Yacometti]

Thanks but I can't read the data from the "To Workspace" block during simulation. I understand it only saves the data to workspace once the simulation is over. The only solution for reading data during simulation seems to be using RunTime objects, or did I misunderstand your first step?