Reading the Real-Time Position after Simulation Completion in SOFA

[MONArfi]

Hello all,

I am working with a soft trunk-like robot that has four cable actuators in SOFA, and I want to read its real-time position after the simulation is complete. In Python, I have created a MechanicalObject named 'dofs' which contains position and velocity. During the simulation, I can observe the position and velocity of 'dofs' under each cable.

I have researched and found that I need to use WriteStates, open(), and read() functions to achieve this. However, I am unsure of the exact steps to do so.

In Python I have:
cable_pos=cableL.addObject('MechanicalObject', name='dofs', position=pullPoint[i]+[pos.toList() for pos in position])

1. How should I modify the following line?

cableL.createObject('WriteState', filename='cablePos.txt', writeF='true', period='0.1', listening="1")

And, after the below code,
simulation = node.addChild('Simulation')

2. What should I write to read the position states?

[EulalieCoevoet]

Hello,

This cableL.createObject('WriteState', filename='cablePos.txt', writeF='true', period='0.1', listening="1") will save the position of the cable's passing points. Is that what you need?
Just in case, if you want extract the position of all the nodes of your FEM mesh, or just the end effector, you should put the component WriteState below the corresponding MechanicalObject.

Do you need to read those positions to analyse them? With another software maybe?

[MONArfi]

Hi,
Thanks for your response,
The above code results as follows:

Now, I just want to read it and simply draw that real-time data by Matplotlib. How can I read them in Python after the simulation completion?

Thank you

[EulalieCoevoet]

Well at this point you no longer needs SOFA.
So I'll let you google how to read a file with python and how to use Matplotlib.

[MONArfi]

OK, Thank you very much.