build123d/docs/tutorial_joints.py

"""

name: tutorial_joints.py
by:   Gumyr
date: December 27h 2022

desc:

    This example a box with a lid attached with a hinge.

license:

    Copyright 2022 Gumyr

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

        http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
"""
# [import]
from build123d import *


# [Hinge Class]
class Hinge(Compound):
    """Hinge

    Half a simple hinge with several joints. The joints are:
    - "leaf": RigidJoint where hinge attaches to object
    - "hinge_axis": RigidJoint (inner) or RevoluteJoint (outer)
    - "hole0", "hole1", "hole2": CylindricalJoints for attachment screws

    Args:
        width (float): width of one leaf
        length (float): hinge length
        barrel_diameter (float): size of hinge pin barrel
        thickness (float): hinge leaf thickness
        pin_diameter (float): hinge pin diameter
        inner (bool, optional): inner or outer half of hinge . Defaults to True.
    """

    def __init__(
        self,
        width: float,
        length: float,
        barrel_diameter: float,
        thickness: float,
        pin_diameter: float,
        inner: bool = True,
    ):
        # The profile of the hinge used to create the tabs
        with BuildPart() as hinge_profile:
            with BuildSketch():
                for i, loc in enumerate(
                    GridLocations(0, length / 5, 1, 5, align=(Align.MIN, Align.MIN))
                ):
                    if i % 2 == inner:
                        with Locations(loc):
                            Rectangle(width, length / 5, align=(Align.MIN, Align.MIN))
                Rectangle(
                    width - barrel_diameter,
                    length,
                    align=(Align.MIN, Align.MIN),
                )
            extrude(amount=-barrel_diameter)

        # The hinge pin
        with BuildPart() as pin:
            Cylinder(
                radius=pin_diameter / 2,
                height=length,
                align=(Align.CENTER, Align.CENTER, Align.MIN),
            )
            with BuildPart(pin.part.faces().sort_by(Axis.Z)[-1]) as pin_head:
                Cylinder(
                    radius=barrel_diameter / 2,
                    height=pin_diameter,
                    align=(Align.CENTER, Align.CENTER, Align.MIN),
                )
            fillet(
                pin_head.edges(Select.LAST).filter_by(GeomType.CIRCLE),
                radius=pin_diameter / 3,
            )

        # Either the external and internal leaf with joints
        with BuildPart() as leaf_builder:
            with BuildSketch():
                with BuildLine():
                    l1 = Line((0, 0), (width - barrel_diameter / 2, 0))
                    l2 = RadiusArc(
                        l1 @ 1,
                        l1 @ 1 + Vector(0, barrel_diameter),
                        -barrel_diameter / 2,
                    )
                    l3 = RadiusArc(
                        l2 @ 1,
                        (
                            width - barrel_diameter,
                            barrel_diameter / 2,
                        ),
                        -barrel_diameter / 2,
                    )
                    l4 = Line(l3 @ 1, (width - barrel_diameter, thickness))
                    l5 = Line(l4 @ 1, (0, thickness))
                    Line(l5 @ 1, l1 @ 0)
                make_face()
                with Locations(
                    (width - barrel_diameter / 2, barrel_diameter / 2)
                ) as pin_center:
                    Circle(pin_diameter / 2 + 0.1 * MM, mode=Mode.SUBTRACT)
            extrude(amount=length)
            add(hinge_profile.part, rotation=(90, 0, 0), mode=Mode.INTERSECT)

            # Create holes for fasteners
            with Locations(leaf_builder.part.faces().filter_by(Axis.Y)[-1]):
                with GridLocations(0, length / 3, 1, 3):
                    holes = CounterSinkHole(3 * MM, 5 * MM)
            # Add the hinge pin to the external leaf
            if not inner:
                with Locations(pin_center.locations[0]):
                    add(pin.part)

            # [Create the Joints]
            #
            # Leaf attachment
            RigidJoint(
                label="leaf",
                to_part=leaf_builder.part,
                joint_location=Location(
                    (width - barrel_diameter, 0, length / 2), (90, 0, 0)
                ),
            )
            # [Hinge Axis] (fixed with inner)
            if inner:
                RigidJoint(
                    "hinge_axis",
                    leaf_builder.part,
                    Location((width - barrel_diameter / 2, barrel_diameter / 2, 0)),
                )
            else:
                RevoluteJoint(
                    "hinge_axis",
                    leaf_builder.part,
                    axis=Axis(
                        (width - barrel_diameter / 2, barrel_diameter / 2, 0), (0, 0, 1)
                    ),
                    angular_range=(90, 270),
                )
            # [Fastener holes]
            hole_locations = [hole.location for hole in holes]
            for hole, hole_location in enumerate(hole_locations):
                CylindricalJoint(
                    label="hole" + str(hole),
                    to_part=leaf_builder.part,
                    axis=hole_location.to_axis(),
                    linear_range=(-2 * CM, 2 * CM),
                    angular_range=(0, 360),
                )
            # [End Fastener holes]

        super().__init__(leaf_builder.part.wrapped, joints=leaf_builder.part.joints)
        # [Hinge Class]


# [Create instances of the two leaves of the hinge]
hinge_inner = Hinge(
    width=5 * CM,
    length=12 * CM,
    barrel_diameter=1 * CM,
    thickness=2 * MM,
    pin_diameter=4 * MM,
)
hinge_outer = Hinge(
    width=5 * CM,
    length=12 * CM,
    barrel_diameter=1 * CM,
    thickness=2 * MM,
    pin_diameter=4 * MM,
    inner=False,
)

# [Create the box with a RigidJoint to mount the hinge]
with BuildPart() as box_builder:
    box = Box(30 * CM, 30 * CM, 10 * CM)
    offset(amount=-1 * CM, openings=box_builder.faces().sort_by(Axis.Z)[-1])
    # Create a notch for the hinge
    with Locations((-15 * CM, 0, 5 * CM)):
        Box(2 * CM, 12 * CM, 4 * MM, mode=Mode.SUBTRACT)
    bbox = box.bounding_box()
    with Locations(
        Plane(origin=(bbox.min.X, 0, bbox.max.Z - 30 * MM), z_dir=(-1, 0, 0))
    ):
        with GridLocations(0, 40 * MM, 1, 3):
            Hole(3 * MM, 1 * CM)
    RigidJoint(
        "hinge_attachment",
        box_builder.part,
        Location((-15 * CM, 0, 4 * CM), (180, 90, 0)),
    )

# [Demonstrate that objects with Joints can be moved and the joints follow]
box = box_builder.part.moved(Location((0, 0, 5 * CM)))

# [The lid with a RigidJoint for the hinge]
with BuildPart() as lid_builder:
    Box(30 * CM, 30 * CM, 1 * CM, align=(Align.MIN, Align.CENTER, Align.MIN))
    with Locations((2 * CM, 0, 0)):
        with GridLocations(0, 40 * MM, 1, 3):
            Hole(3 * MM, 1 * CM)
    RigidJoint(
        "hinge_attachment",
        lid_builder.part,
        Location((0, 0, 0), (0, 0, 180)),
    )
lid = lid_builder.part

# [A screw to attach the hinge to the box]
m6_screw = import_step("M6-1x12-countersunk-screw.step")
m6_joint = RigidJoint("head", m6_screw, Location((0, 0, 0), (0, 0, 0)))
# [End of screw creation]

# [Export SVG files]
#
# SVG Export options
svg_opts = {"pixel_scale": 5, "show_axes": False, "show_hidden": True}
Compound.make_compound([box, box.joints["hinge_attachment"].symbol]).export_svg(
    "assets/tutorial_joint_box.svg", (-100, 100, 150), (0, 0, 1), svg_opts=svg_opts
)
Compound.make_compound(
    [
        hinge_inner,
        hinge_inner.joints["leaf"].symbol,
        hinge_inner.joints["hinge_axis"].symbol,
        hinge_inner.joints["hole0"].symbol,
        hinge_inner.joints["hole1"].symbol,
        hinge_inner.joints["hole2"].symbol,
    ]
).export_svg(
    "assets/tutorial_joint_inner_leaf.svg",
    (100, 100, -50),
    (0, 0, 1),
    svg_opts=svg_opts,
)
Compound.make_compound(
    [
        hinge_outer,
        hinge_outer.joints["leaf"].symbol,
        hinge_outer.joints["hinge_axis"].symbol,
        hinge_outer.joints["hole0"].symbol,
        hinge_outer.joints["hole1"].symbol,
        hinge_outer.joints["hole2"].symbol,
    ]
).export_svg(
    "assets/tutorial_joint_outer_leaf.svg",
    (100, 100, -50),
    (0, 0, 1),
    svg_opts=svg_opts,
)
Compound.make_compound([box, hinge_outer]).export_svg(
    "assets/tutorial_joint_box_outer.svg",
    (-100, -100, 50),
    (0, 0, 1),
    svg_opts=svg_opts,
)
Compound.make_compound([lid, lid.joints["hinge_attachment"].symbol]).export_svg(
    "assets/tutorial_joint_lid.svg", (-100, 100, 150), (0, 0, 1), svg_opts=svg_opts
)
Compound.make_compound([m6_screw, m6_joint.symbol]).export_svg(
    "assets/tutorial_joint_m6_screw.svg",
    (-100, 100, 150),
    (0, 0, 1),
    svg_opts={"pixel_scale": 20, "show_axes": False, "show_hidden": False},
)

# [Connect Box to Outer Hinge]
box.joints["hinge_attachment"].connect_to(hinge_outer.joints["leaf"])
# [Connect Box to Outer Hinge]
Compound.make_compound([box, hinge_outer]).export_svg(
    "assets/tutorial_joint_box_outer.svg",
    (-100, -100, 50),
    (0, 0, 1),
    svg_opts=svg_opts,
)
# [Connect Hinge Leaves]
hinge_outer.joints["hinge_axis"].connect_to(hinge_inner.joints["hinge_axis"], angle=120)
# [Connect Hinge Leaves]
Compound.make_compound([box, hinge_outer, hinge_inner]).export_svg(
    "assets/tutorial_joint_box_outer_inner.svg",
    (-100, -100, 50),
    (0, 0, 1),
    svg_opts=svg_opts,
)
# [Connect Hinge to Lid]
hinge_inner.joints["leaf"].connect_to(lid.joints["hinge_attachment"])
# [Connect Hinge to Lid]
Compound.make_compound([box, hinge_outer, hinge_inner, lid]).export_svg(
    "assets/tutorial_joint_box_outer_inner_lid.svg",
    (-100, -100, 50),
    (0, 0, 1),
    svg_opts=svg_opts,
)
# [Connect Screw to Hole]
hinge_outer.joints["hole2"].connect_to(m6_joint, position=5 * MM, angle=30)
# [Connect Screw to Hole]

# [Add labels]
box.label = "box"
lid.label = "lid"
hinge_outer.label = "outer hinge"
hinge_inner.label = "inner hinge"
m6_screw.label = "M6 screw"

# [Create assembly]
box_assembly = Compound(label="assembly", children=[box, lid, hinge_inner, hinge_outer])
# [Display assembly]
print(box_assembly.show_topology())

# [Add to the assembly by assigning the parent attribute of an object]
m6_screw.parent = box_assembly
print(box_assembly.show_topology())

# [Check that the components in the assembly don't intersect]
child_intersect, children, volume = box_assembly.do_children_intersect(
    include_parent=False
)
print(f"do children intersect: {child_intersect}")
if child_intersect:
    print(f"{children} by {volume:0.3f} mm^3")

# [Export Final SVG file]
box_assembly.export_svg(
    "assets/tutorial_joint.svg", (-100, -100, 50), (0, 0, 1), svg_opts=svg_opts
)


if "show_object" in locals():
    show_object(box, name="box", options={"alpha": 0.8})
    # show_object(box.joints["hinge_attachment"].symbol, name="box attachment point")
    show_object(hinge_outer, name="hinge_outer")
    # show_object(hinge_outer.joints["leaf"].symbol, name="hinge_outer leaf joint")
    # show_object(hinge_outer.joints["hinge_axis"].symbol, name="hinge_outer hinge axis")
    show_object(lid, name="lid")
    # show_object(lid.joints["hinge_attachment"].symbol, name="lid attachment point")
    show_object(hinge_inner, name="hinge_inner")
    # show_object(hinge_inner.joints["leaf"].symbol, name="hinge_inner leaf joint")
    # show_object(hinge_inner.joints["hinge_axis"].symbol, name="hinge_inner hinge axis")
    for hole in [0, 1, 2]:
        show_object(
            hinge_inner.joints["hole" + str(hole)].symbol,
            name="hinge_inner hole " + str(hole),
        )
        show_object(
            hinge_outer.joints["hole" + str(hole)].symbol,
            name="hinge_outer hole " + str(hole),
        )
    show_object(m6_screw, name="m6 screw")
    show_object(m6_joint.symbol, name="m6 screw symbol")
    show_object(box_assembly, name="box assembly")