Unexpected output of CSGRegion and RegionDifference?

Questions
,
1

The output of CSGRegion and RegionDifference in the attachment is wrong. What’s wrong? Please enlighten me. thank you！

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CSGRegion and RegionDifference output errors, what’s wrong.nb (200 KB)

2

CSRegion can only work with “basic” shapes. The supported shapes are listed in the documentation.

3

Thanks!
RegionDifference can only work with “basic” shapes？

4

Here is a suggested answer from Wolfram’s team

Needs["NDSolve`FEM`"]
Needs["OpenCascadeLink`"]
cyl = OpenCascadeShape[Cylinder[{{-9, 0, 0}, {9, 0, 0}}, 7]];
dg = DiscretizeGraphics[ExampleData[{"Geometry3D", "SpaceShuttle"}]];
orbiter = OpenCascadeShape[ToBoundaryMesh[dg]];
shape = OpenCascadeShapeDifference[cyl, orbiter];
bmesh = OpenCascadeShapeSurfaceMeshToBoundaryMesh[shape];
bmesh["Wireframe"]
5

Many thanks to the Wolfram’s team and their professional guidance! Through the following guidance, I once again felt the power of Wolfram Mathematica.
I hope that I can use relevant research results to repay everyone’s help in the near future.