59 lines
2.0 KiB
Python
59 lines
2.0 KiB
Python
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"""
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A fibre, for bearing tension
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"""
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import cadquery as Cq
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from dataclasses import dataclass
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import nhf.utils
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def tension_fibre(
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length: float,
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hole_diam: float,
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hole_twist: float=0,
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thickness: float=0.5) -> Cq.Workplane:
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"""
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A fibre which holds tension, with an eyes on each end.
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"""
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eye_female = Cq.Solid.makeTorus(
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radius1=hole_diam/2 + thickness/2,
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radius2=thickness/2,
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dir=(1,0,0),
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)
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hole_length_male = hole_diam * 2.5
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hole_height_male = hole_diam * 1.2
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eye_male = Cq.Solid.makeBox(
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length=hole_length_male + thickness * 2,
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width=thickness,
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height=hole_height_male + thickness * 2,
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).located(
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Cq.Location((-hole_length_male/2-thickness, -thickness/2, -hole_height_male/2-thickness))
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).cut(Cq.Solid.makeBox(
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length=hole_length_male,
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width=thickness,
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height=hole_height_male,
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).located(Cq.Location((-hole_length_male/2, -thickness/2, -hole_height_male/2))))
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height = length - hole_diam - thickness
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assert height > 0, "String is too short to support the given hole sizes"
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h1 = length/2 - hole_diam/2 - thickness/2
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h2 = length/2 - hole_height_male - thickness/2
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result = (
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Cq.Workplane('XY')
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.cylinder(
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radius=thickness/2,
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height=h1,
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centered=(True, True, False),
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)
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.copyWorkplane(Cq.Workplane('YX'))
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.cylinder(
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radius=thickness/2,
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height=h2,
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centered=(True, True, False),
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)
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.union(eye_female.located(Cq.Location((0, 0,length/2))))
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.union(eye_male.located(Cq.Location((0, 0,-length/2+hole_height_male/2+thickness/2), (0,0,1), hole_twist)))
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)
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result.copyWorkplane(Cq.Workplane(Cq.Plane(origin=(0,0,length/2), normal=(1,0,0)))).tagPlane("female")
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conn1_normal, _ = (Cq.Location((0,0,0),(0,0,1),hole_twist) * Cq.Location((1,0,0))).toTuple()
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result.copyWorkplane(Cq.Workplane(Cq.Plane(origin=(0,0,-length/2), normal=conn1_normal))).tagPlane("male")
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return result
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