Previously, the fillet started at a fixed value, tailored at 20° pressure
angle, a fillet radius of 0.375 and a dedendum of 1.25. With PR #8184
those values became user-adjustable and thus the assumptions of the
original code are not fullfilled any more. This resulted in significant
artefacts, especially for higher pressure angles or smaller dedendums as
commonly found in splines.
This commit actually calculates the junction between fillet and involute
so that the tangents of the both curves match.
The mathematical approach is described in source code comments.
The change in the fillet calculation also affects compatibility with
files generated by earlier versions of FreeCAD. Those changes are way
below 0.1% per tooth, however the earlier test required absolute equality
down to the micron. This was relaxed and also changed to a relative, per
tooth, tolerance.
There is one particular case where the new algorithm performs slightly
worse, though. That is when the fillet radius is too large to the
dedendum, i.e. resulting in a single arc instead of two fillets, and
effectively cannibalizes some of the clearance. This happens with internal
gears having less than 25 teeth. At about 15 teeth it becomes visible
that the fillet is not 100% tanget any more. However, as such a low
number of teeth is highly unusual for internal gears and the effect,
although noticeable, is minor, the overall benefits of the new algorithm
outweighs the drawbacks. And now with the fillet radius being adjustable
it is easy to fix, too.
The technical reason is that the tangency is calculated correctly, but
the fillet circle is displaced aferwards to avoid an overlap of the two
fillets. For the new fillet position, the tangents do not align any more.
This little script has proven to be a vauable debugging aid, so it got
some love. All the new properties from #8184 can now be set, together
with the option to generate internal gears.
- it is a well-known and often feed-backed missing feature that SectionCuttings fails for intersecting objects.
To resolve this, the objects must be put int a BooleanFragments object.
- this PR adds this functionality as option.
- since a BooleanFragments objects has a specific color, the different colors of the objects cannot be preserved. Because of this disadvantage, the BooleanFragments option will not be the default.
- this PR also modernize all for loops
- the typical workflow is to change e.g. a constraint setting or material property and to check how and if this change changes the simulation result. it is therefore very annoying that on every call of a task panel the results are hidden.
This PR changes this to hide only meshes and the filter functions but to keep the results. If a user don't like to see results for example to select faces, he hides results anyway.
- uses the constraint for 2D magnetodynamics to perform e.g. Elmer's tutorial non. 15
- modify the Material manager to get rid of magnetization but keep the vectorial functionality because in future there will be support for e.g. birefringence materials etc.
- for harmonically driven forces, the results of course also have an imaginary part. Elmer outputs the real and the imaginary parts as separate result field. However, for several applications one needs the absolute (sqrt(Re^2+Im^2)
- therefore offer also absolute field if there are real/imaginary results
- for electromagnetics we have vector fields and thus need to specify components
- as first step use the new material "Magnetization"
- also get rid of annoying debug messages output on normal use in the material dialog