Cosplay/nhf/touhou/houjuu_nue/wing.py

"""
This file describes the shapes of the wing shells. The joints are defined in
`__init__.py`.
"""
import math
import cadquery as Cq
from nhf import Material, Role
from nhf.parts.joints import HirthJoint

def wing_root_profiles(
        base_sweep=150,
        wall_thickness=8,
        base_radius=40,
        middle_offset=30,
        middle_height=80,
        conn_width=40,
        conn_height=100) -> tuple[Cq.Wire, Cq.Wire]:
    assert base_sweep < 180
    assert middle_offset > 0
    theta = math.pi * base_sweep / 180
    c, s = math.cos(theta), math.sin(theta)
    c_1, s_1 = math.cos(theta * 0.75), math.sin(theta * 0.75)
    c_2, s_2 = math.cos(theta / 2), math.sin(theta / 2)
    r1 = base_radius
    r2 = base_radius - wall_thickness
    base = (
        Cq.Sketch()
        .arc(
            (c * r1, s * r1),
            (c_1 * r1, s_1 * r1),
            (c_2 * r1, s_2 * r1),
        )
        .arc(
            (c_2 * r1, s_2 * r1),
            (r1, 0),
            (c_2 * r1, -s_2 * r1),
        )
        .arc(
            (c_2 * r1, -s_2 * r1),
            (c_1 * r1, -s_1 * r1),
            (c * r1, -s * r1),
        )
        .segment(
            (c * r1, -s * r1),
            (c * r2, -s * r2),
        )
        .arc(
            (c * r2, -s * r2),
            (c_1 * r2, -s_1 * r2),
            (c_2 * r2, -s_2 * r2),
        )
        .arc(
            (c_2 * r2, -s_2 * r2),
            (r2, 0),
            (c_2 * r2, s_2 * r2),
        )
        .arc(
            (c_2 * r2, s_2 * r2),
            (c_1 * r2, s_1 * r2),
            (c * r2, s * r2),
        )
        .segment(
            (c * r2, s * r2),
            (c * r1, s * r1),
        )
        .assemble(tag="wire")
        .wires().val()
    )
    assert isinstance(base, Cq.Wire)

    # The interior sweep is given by theta, but the exterior sweep exceeds the
    # interior sweep so the wall does not become thinner towards the edges.
    # If the exterior sweep is theta', it has to satisfy
    #
    # sin(theta) * r2 + wall_thickness = sin(theta') * r1
    x, y = conn_width / 2, middle_height / 2
    t = wall_thickness
    dx = middle_offset
    middle = (
        Cq.Sketch()
        # Interior arc, top point
        .arc(
            (x - t, y - t),
            (x - t + dx, 0),
            (x - t, -y + t),
        )
        .segment(
            (x - t, -y + t),
            (-x, -y+t)
        )
        .segment((-x, -y))
        .segment((x, -y))
        # Outer arc, bottom point
        .arc(
            (x, -y),
            (x + dx, 0),
            (x, y),
        )
        .segment(
            (x, y),
            (-x, y)
        )
        .segment((-x, y-t))
        #.segment((x2, a))
        .close()
        .assemble(tag="wire")
        .wires().val()
    )
    assert isinstance(middle, Cq.Wire)

    x, y = conn_width / 2, conn_height / 2
    t = wall_thickness
    tip = (
        Cq.Sketch()
        .segment((-x, y), (x, y))
        .segment((x, -y))
        .segment((-x, -y))
        .segment((-x, -y+t))
        .segment((x-t, -y+t))
        .segment((x-t, y-t))
        .segment((-x, y-t))
        .close()
        .assemble(tag="wire")
        .wires().val()
    )
    return base, middle, tip


def wing_root(joint: HirthJoint,
              bolt_diam: int = 12,
              union_tol=1e-4,
              attach_diam=8,
              conn_width=40,
              conn_height=100,
              wall_thickness=8) -> Cq.Assembly:
    """
    Generate the contiguous components of the root wing segment
    """
    tip_centre = Cq.Vector((-150, 0, -80))
    attach_points = [
        (15, 0),
        (40, 0),
    ]
    root_profile, middle_profile, tip_profile = wing_root_profiles(
        conn_width=conn_width,
        conn_height=conn_height,
        wall_thickness=8,
    )
    middle_profile = middle_profile.located(Cq.Location(
        (-40, 0, -40), (0, 30, 0)
    ))
    antetip_profile = tip_profile.located(Cq.Location(
        (-95, 0, -75), (0, 60, 0)
    ))
    tip_profile = tip_profile.located(Cq.Location(
        tip_centre, (0, 90, 0)
    ))
    profiles = [
        root_profile,
        middle_profile,
        antetip_profile,
        tip_profile,
    ]
    result = None
    for p1, p2 in zip(profiles[:-1], profiles[1:]):
        seg = (
            Cq.Workplane('XY')
            .add(p1)
            .toPending()
            .workplane() # This call is necessary
            .add(p2)
            .toPending()
            .loft()
        )
        if result:
            result = result.union(seg, tol=union_tol)
        else:
            result = seg
    result = (
        result
        # Create connector holes
        .copyWorkplane(
            Cq.Workplane('bottom', origin=tip_centre + Cq.Vector((0, -50, 0)))
        )
        .pushPoints(attach_points)
        .hole(attach_diam)
    )
    # Generate attach point tags

    for sign in [False, True]:
        y = conn_height / 2 - wall_thickness
        side = "bottom" if sign else "top"
        y = y if sign else -y
        plane = (
            result
            # Create connector holes
            .copyWorkplane(
                Cq.Workplane(side, origin=tip_centre +
                             Cq.Vector((0, y, 0)))
            )
        )
        for i, (px, py) in enumerate(attach_points):
            (
                plane
                .moveTo(px, py)
                .eachpoint(Cq.Vertex.makeVertex(0, 0, 0))
                .tag(f"conn_{side}{i}")
            )

    result.faces("<Z").tag("base")
    result.faces(">X").tag("conn")

    j = (
        joint.generate(is_mated=True)
        .faces("<Z")
        .hole(bolt_diam)
    )

    color = Material.PLASTIC_PLA.color
    result = (
        Cq.Assembly()
        .add(result, name="scaffold", color=color)
        .add(j, name="joint", color=Role.CHILD.color,
             loc=Cq.Location((0, 0, -joint.total_height)))
    )
    return result