Building a controller to move the beam

[Slykkey]

Hello,

I see the InterventionalRadiologyController which I use to automatically move my designed catheter in a certain direction. I wanted to know if it was possible to design a controller which took inputs through a CAN Bus and translate it to SOFA. If this is possible, which states of the object do I have to change with respect to the controller? Please let me know if there is a thread based on the question as well. Thanks in advance!

[epernod]

Hi @Slykkey ,

I don't know what is CAN Bus but if you can communicate with it directly in c++. I would recommend to write a new controller similar to this one: https://github.com/sofa-framework/BeamAdapter/blob/4f0f30c7025740e808865d392c1bac7df3627e9b/src/BeamAdapter/component/controller/BeamAdapterActionController.inl#L70
and instead of listening to key events you should listen to your event and push the BeamAction to the buffer of action which will be used by the IRController

++Erik

[Slykkey]

Hello @epernod ,

It connects my controller to the PC which reads messages sent from the controller. I read this on Python using a module on Python. Is it possible to write the same in Python? If not I can communicate between Python and C++. Is the BeamAdapterActionController something you can use to move the instrument with events? I currently use InterventionalRadiologyController and it automatically moves the instrument in a desired direction. Let me know if I can rewrite IRController or if I have to make one similar to the one you mentioned.

[hugtalbot]

Hi @Slykkey

Yes BeamAdapterActionController does this control of the beam. See the link shared by Erik you will see the different int values that the data actions can take (see the switch).

Small question @epernod: at first sight, I do not see in the inl the use of the data actionString. Is this normal ?

[epernod]

you are right, this has not been finished. Only the d_actions is used for the moment where action are coded as int.
corresponding to this enum: https://github.com/sofa-framework/BeamAdapter/blob/4f0f30c7025740e808865d392c1bac7df3627e9b/src/BeamAdapter/utils/BeamActions.h#L28

yes.. some doc might be needed here 😄

[epernod]

@Slykkey ,
So I see several options to do what you want:

1. The BeamAdapterActionController handle a list of BeamAdapterAction. It has been designed to export and replay actions but you can use it on the fly. If you put it in d_writeMode = False, at each new timestep it will check if an action need to be send to the InterventialRadiologyController at this timestep. See this method. So you can add a pythonScriptController to update the list of d_timeSteps and d_actions. I'm just not 100% sure you won't have a delay of 1 timestep, because I don't know which will be first executed between the pythonScriptController and the BeamAdapterActionController
2. You modify the BeamAdapterActionController to be able to update the m_currAction as a Data and you access it using a pythonScriptController . You need to put the d_writeMode to True for this solution.
3. You add a binding in python to the method applyAction in the InterventionalRadiologyController

I hope this is understandable 😄 and will help you

[Slykkey]

@hugtalbot @epernod ,
Hello guys, thanks for the quick response. By reading through the code, I see that the value xtip and rotationInstrument are the ones used to modify movement and rotation. If I can change these values with respect to my controller, will that make it work? Please let me know if this is a viable solution.

[epernod]

Hi, yes if you prefer you can do that but be careful to move the xtip accordingly to the step size.
That is why I suggest more to use the method applyAction(sofa::beamadapter::BeamAdapterAction action). If you reproduce the same code as this method in your pythonScriptController, it should work fine.

[github-actions[bot]]

⚠️ ⚠️ ⚠️
@Slykkey
Feedback has been given to you by the project reviewers, however we have not received a response from you. Without further news in the coming weeks, this discussion will be automatically closed in order to keep this forum clean and fresh 🌱 Thank you for your understanding

[hugtalbot]

Do not hesitate to share any update an piece of your controller @Slykkey

[Slykkey]

@hugtalbot Hello,

The controller works completely fine. I do have one question though, it starts to get laggy after a few seconds into the simulation and also gets extremely laggy during interactions. Is there a way to fix this? I assume it's because of the FPS drop and hence delaying the messages coming from the controller and causing an appropriate action on SOFA. Please let me know if there is a fix or if you could provide any feedback!

[hugtalbot]

This might be due to the number of contact points.
You should look at:

• the collision mesh refinement
• see which proximity code you are using (could you try the LocalMinDistance)
• see the page on performance : https://www.sofa-framework.org/community/doc/using-sofa/performances/improve-performances/

If this does not suffice, please open a new dedicated topic with a maximum of information (possibly the scene with all meshes)