Delsys Signal to MATLAB Simulink

Hello everyone!

I am having troubles streaming emg signals to Simulink to run a continuous expereiment where I can take those live emg signals and analyze them. I was using the TCP/IP client receive block in Simulink to establish the connection between the delsys system and Simulink (ran a previous matlab script in order to establish the Delsys/Matlab connection), but the data points are scattered and though the peaks of the signal rise when muscle contractions occur, the emg signal produces square waves that have many holes in it. Thank you in advance

[Paromita]

Hi @Caly and @Anshuman!

I’m also working on streaming data from the Delsys system to MATLAB. I’m not using Simulink — instead, I’m connecting through the command:

client = tcpclient('localhost', 50040);

The connection seems to be successful since I can see “remote 1 user” in the Trigno Control Utility. However, after using read/write commands to access the data, I’m not seeing any output saved in my data folder.

Do you have any idea what might be causing this issue? I can also share my code if that would help troubleshoot it better.

Thank you so much for the help!

Answer 1

[Anshuman]

Hi Caly,

The issue you're encountering with scattered data points and "square waves that have many holes in it" could be due to several factors ranging from the way the TCP/IP connection is set up, to the processing of the incoming data stream in Simulink. Here are few things that you can try at your end:

On TCP/IP side:

1. The default buffer size might be too small, leading to data loss. Increase the buffer size to ensure that all incoming data can be accommodated.
2. If the block is in non-blocking mode, it might not wait for enough data to arrive before proceeding, leading to "holes" in your data. Try setting it to blocking mode.

Simulink Model configuration:

1. The execution rate of the Simulink model might be too slow to process the incoming data in real-time. Try increasing the fixed-step size.
2. If the data is sent in chunks, make sure that your processing script or Simulink model is correctly reassembling these chunks into a continuous stream.

[Caly]

Thank you so much for your response! The "enable blocking" option fixed what I had trouble with!