SubMapping Error Point Not Found

[Shaswat]

Hi,

I am trying to simulate a Tendon-Driven robot. I create SubMapping between the Disks and BackBone. But I get the following error every time I run the analysis.

[ERROR]   [SofaPython3::SceneLoader] AttributeError: Missing attribute: getObject

At:
  TendonRobotwithConstraint.py3scn(57): createScene

[ERROR]   [SubsetMapping(SubsetMapping)] Point 12=5.85271 5 -29.4236 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 13=5.85271 0 -29.4236 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 15=11.4805 0 -27.7164 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 16=11.4805 5 -27.7164 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 17=16.6671 5 -24.9441 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 18=16.6671 0 -24.9441 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 21=24.9441 0 -16.6671 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 22=24.9441 5 -16.6671 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 23=27.7164 5 -11.4805 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 24=27.7164 0 -11.4805 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 26=29.4236 5 5.85271 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 28=29.4236 0 5.85271 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 29=27.7164 0 11.4805 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 30=27.7164 5 11.4805 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 31=24.9441 5 16.6671 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 33=24.9441 0 16.6671 not found in input model within a radius of 1e-05.
[ERROR]   [SubsetMapping(SubsetMapping)] Point 35=16.6671 0 24.9441 not found in input model within a radius of 1e-05.

All the simulation files are uploaded in link

I would really appreciate it if you could help me with this.

Regards
Shaswat

[Hugo]

Hey @shaswat2001

The error given by the SubsetMapping is explicit: points from one mesh (probably the submesh) is not considered as inside the input mesh.

But in fact, from what I see from your files, you are aiming at extracting the surface of your *.msh mesh. To do so, you should rather use a TopologicalMapping. See for instance the Tetra2TriangleTopologicalMapping example. Let me know whether this is what you are looking for.

Best wishes,

Hugo

[Shaswat]

Hi Hugo,

I am trying to create a mapping between my backbone and tendon disk so that when the cable actuates, both the bodies would move. That’s why I was using SubMapping. I will give Tetra2TriangleTopologicalMapping a try and see if it works. Do let me know if there is any another method to model a tendon driven robot.

Regards
Shaswat

[Hugo]

Hey @shaswat2001

The question is rather which body is actually actuated by your cable?
Could you share the scene you are starting from?

Best wishes,

Hugo

[Shaswat]

There are two bodies. One is backbone passing through the center of the robot. Other is set of spacer disks. The tendons pass through the spacer disks.

I have been able to create a mapping between the disk and backbone using Barycentric Mapping. The mapping seems to be working but when I change the displacement of the tendons, I get erratic behavior in the robot. Is this because of the mapping or something else?

All the python scripts are in the GitHub repository.

Regards
Shaswat

[Author]

Posts