Blender Terminal: It is often helpful to look at the Blender Terminal. It gives detailed error messages and warnings that help to trace back the error. The most common problems are listed below
Project name text field: You always need to remove the text "untitled" in the field at the bottom of the exportMesh2HRTF export window the first time you open in it in a new Blender project.
KeyError: 'bpypropcollection[key]: key "Reference" not found: Make sure you mesh is named 'Reference' (case sensitive). The same applies to materials (e.g. 'Left ear') and sources (e.g. 'Point source')
TypeError: not all arguments converted during string formatting: Try the Triangulate modifier
TypeError: Converting py args to operator properties: enum "EDIT" not found in ('OBJECT'): Solution: This error occurs when "Edit Mode" hasn't been established yet in the Blender project for some reason. Click on one of the objects and make sure "Edit Mode" is available in the drop-down menu at the top left which is usually set to "Object Mode".
RuntimeError: Operator bpy.ops.object.transformapply.poll() failed, context is incorrect: Go to the Object Mode before the export (this problem should not occur anymore).
Missing or extreme values in the HRTF: Missing or extreme values can appear if the simulation did not converge. If this is the case the text 'Warning: Maximum number of iterations is reached' appears in the Nc.out file. In many cases a bad mesh is the problem. Make sure that
- all face normals point outwards,
- there are no intersections in the mesh,
- there are no highly irregular triangles in the mesh,
- the transition between small and large triangles is smooth.
If the problem still persists, a more regular mesh might be obtained through re-meshing. The last possibility is to manually change the clustering of NumCalc's ML-FMM-BEM. To do this, change the following line in the NC.inp file contained in your project folder under NumCalc/source_x
. Search for Main Parameters II
and set the fourth number to 0.05 after wich the line should look like this 0 1 0 0.05 0 0 0
. Once this is done, try to run NumCalc again.
Implausible results for point source simulations: This can happen if the point source is too close to the mesh. From experience at least 0.3 mm distance seems to be a good value for elements with an edge length around 1 mm.
Wiki: Basic_Project_export
Wiki: Mesh2HRTF 1.0 and above
Wiki: Preparing the mesh