768 lines
27 KiB
Python
768 lines
27 KiB
Python
import math
|
|
from dataclasses import dataclass, field
|
|
from typing import Optional, Tuple
|
|
import cadquery as Cq
|
|
from nhf import Material, Role
|
|
from nhf.build import Model, target, assembly
|
|
from nhf.parts.springs import TorsionSpring
|
|
from nhf.parts.joints import TorsionJoint
|
|
from nhf.parts.box import Hole, MountingBox, box_with_centre_holes
|
|
import nhf.utils
|
|
|
|
TOL = 1e-6
|
|
|
|
@dataclass
|
|
class ShoulderJoint(Model):
|
|
|
|
height: float = 60.0
|
|
torsion_joint: TorsionJoint = field(default_factory=lambda: TorsionJoint(
|
|
radius_track=18,
|
|
radius_rider=18,
|
|
groove_depth=4.8,
|
|
groove_radius_outer=16,
|
|
groove_radius_inner=13,
|
|
track_disk_height=5.0,
|
|
rider_disk_height=5.0,
|
|
# M8 Axle
|
|
radius_axle=3.0,
|
|
spring=TorsionSpring(
|
|
# inner diameter = 9
|
|
radius=9/2 + 1.2,
|
|
thickness=1.3,
|
|
height=7.5,
|
|
),
|
|
rider_slot_begin=0,
|
|
rider_n_slots=1,
|
|
rider_slot_span=0,
|
|
))
|
|
|
|
# On the parent side, drill vertical holes
|
|
|
|
parent_conn_hole_diam: float = 6.0
|
|
# Position of the holes relative
|
|
parent_conn_hole_pos: list[Tuple[float, float]] = field(default_factory=lambda: [
|
|
(15, 8),
|
|
(15, -8),
|
|
])
|
|
|
|
parent_lip_length: float = 25.0
|
|
parent_lip_width: float = 30.0
|
|
parent_lip_thickness: float = 5.0
|
|
parent_lip_ext: float = 40.0
|
|
parent_lip_guard_height: float = 8.0
|
|
|
|
# Measured from centre of axle
|
|
child_lip_length: float = 45.0
|
|
child_lip_width: float = 20.0
|
|
child_conn_hole_diam: float = 6.0
|
|
# Measured from centre of axle
|
|
child_conn_hole_pos: list[float] = field(default_factory=lambda: [25, 35])
|
|
child_core_thickness: float = 3.0
|
|
|
|
# Rotates the torsion joint to avoid collisions or for some other purpose
|
|
axis_rotate_bot: float = 225.0
|
|
axis_rotate_top: float = -225.0
|
|
|
|
directrix_id: int = 0
|
|
angle_neutral: float = 10.0
|
|
|
|
def __post_init__(self):
|
|
assert self.parent_lip_length * 2 < self.height
|
|
|
|
def parent(self, top: bool = False) -> Cq.Assembly:
|
|
joint = self.torsion_joint
|
|
# Thickness of the lip connecting this joint to the wing root
|
|
assert self.parent_lip_width <= joint.radius_track * 2
|
|
assert self.parent_lip_ext > joint.radius_track
|
|
|
|
lip_guard = (
|
|
Cq.Solid.makeBox(
|
|
self.parent_lip_ext,
|
|
self.parent_lip_width,
|
|
self.parent_lip_guard_height)
|
|
.located(Cq.Location((0, -self.parent_lip_width/2 , 0)))
|
|
.cut(Cq.Solid.makeCylinder(joint.radius_track, self.parent_lip_guard_height))
|
|
)
|
|
lip = MountingBox(
|
|
length=self.parent_lip_length,
|
|
width=self.parent_lip_width,
|
|
thickness=self.parent_lip_thickness,
|
|
holes=[
|
|
Hole(x=self.height / 2 - x, y=y)
|
|
for x, y in self.parent_conn_hole_pos
|
|
],
|
|
hole_diam=self.parent_conn_hole_diam,
|
|
generate_side_tags=False,
|
|
)
|
|
# Flip so the lip's holes point to -X
|
|
loc_axis = Cq.Location((0,0,0), (0, 1, 0), -90)
|
|
# so they point to +X
|
|
loc_dir = Cq.Location((0,0,0), (0, 0, 1), 180)
|
|
loc_pos = Cq.Location((self.parent_lip_ext - self.parent_lip_thickness, 0, 0))
|
|
|
|
rot = -self.axis_rotate_top if top else self.axis_rotate_bot
|
|
|
|
result = (
|
|
Cq.Assembly()
|
|
.add(joint.track(), name="track",
|
|
loc=Cq.Location((0, 0, 0), (0, 0, 1), rot))
|
|
.add(lip_guard, name="lip_guard")
|
|
.add(lip.generate(), name="lip", loc=loc_pos * loc_dir * loc_axis)
|
|
)
|
|
return result
|
|
|
|
@target(name="parent-bot")
|
|
def parent_bot(self) -> Cq.Assembly:
|
|
return self.parent(top=False)
|
|
@target(name="parent-top")
|
|
def parent_top(self) -> Cq.Assembly:
|
|
return self.parent(top=True)
|
|
|
|
@property
|
|
def child_height(self) -> float:
|
|
"""
|
|
Calculates the y distance between two joint surfaces on the child side
|
|
of the shoulder joint.
|
|
"""
|
|
joint = self.torsion_joint
|
|
return self.height - 2 * joint.total_height + 2 * joint.rider_disk_height
|
|
|
|
@target(name="child")
|
|
def child(self) -> Cq.Assembly:
|
|
"""
|
|
Creates the top/bottom shoulder child joint
|
|
"""
|
|
|
|
joint = self.torsion_joint
|
|
assert all(r > joint.radius_rider for r in self.child_conn_hole_pos)
|
|
assert all(r < self.child_lip_length for r in self.child_conn_hole_pos)
|
|
|
|
# Half of the height of the bridging cylinder
|
|
dh = self.height / 2 - joint.total_height
|
|
core_start_angle = 30
|
|
core_end_angle1 = 90
|
|
core_end_angle2 = 180
|
|
|
|
radius_core_inner = joint.radius_rider - self.child_core_thickness
|
|
core_profile1 = (
|
|
Cq.Sketch()
|
|
.arc((0, 0), joint.radius_rider, core_start_angle, core_end_angle1-core_start_angle)
|
|
.segment((0, 0))
|
|
.close()
|
|
.assemble()
|
|
.circle(radius_core_inner, mode='s')
|
|
)
|
|
core_profile2 = (
|
|
Cq.Sketch()
|
|
.arc((0, 0), joint.radius_rider, -core_start_angle, -(core_end_angle2-core_start_angle))
|
|
.segment((0, 0))
|
|
.close()
|
|
.assemble()
|
|
.circle(radius_core_inner, mode='s')
|
|
)
|
|
core = (
|
|
Cq.Workplane('XY')
|
|
.placeSketch(core_profile1)
|
|
.toPending()
|
|
.extrude(dh * 2)
|
|
.copyWorkplane(Cq.Workplane('XY'))
|
|
.placeSketch(core_profile2)
|
|
.toPending()
|
|
.extrude(dh * 2)
|
|
.translate(Cq.Vector(0, 0, -dh))
|
|
)
|
|
assert self.child_lip_width / 2 <= joint.radius_rider
|
|
lip_thickness = joint.rider_disk_height
|
|
lip = box_with_centre_holes(
|
|
length=self.child_lip_length,
|
|
width=self.child_lip_width,
|
|
height=lip_thickness,
|
|
hole_loc=self.child_conn_hole_pos,
|
|
hole_diam=self.child_conn_hole_diam,
|
|
)
|
|
lip = (
|
|
lip
|
|
.copyWorkplane(Cq.Workplane('XY'))
|
|
.cylinder(
|
|
radius=joint.radius_rider,
|
|
height=lip_thickness,
|
|
centered=(True, True, False),
|
|
combine='cut')
|
|
)
|
|
theta = self.torsion_joint.spring.angle_neutral - self.torsion_joint.rider_slot_span
|
|
loc_rotate = Cq.Location((0, 0, 0), (1, 0, 0), 180)
|
|
loc_axis_rotate_bot = Cq.Location((0, 0, 0), (0, 0, 1), self.axis_rotate_bot + self.angle_neutral)
|
|
loc_axis_rotate_top = Cq.Location((0, 0, 0), (0, 0, 1), self.axis_rotate_top + self.angle_neutral)
|
|
result = (
|
|
Cq.Assembly()
|
|
.add(core, name="core", loc=Cq.Location())
|
|
.add(joint.rider(rider_slot_begin=-90, reverse_directrix_label=True), name="rider_top",
|
|
loc=loc_axis_rotate_top * Cq.Location((0, 0, dh), (0, 0, 1), -90) * Cq.Location((0, 0, 0), (0, 0, 1), theta))
|
|
.add(joint.rider(rider_slot_begin=180), name="rider_bot",
|
|
loc=loc_axis_rotate_bot * Cq.Location((0, 0, -dh), (0, 0, 1), -90) * loc_rotate)
|
|
.add(lip, name="lip_top",
|
|
loc=Cq.Location((0, 0, dh)))
|
|
.add(lip, name="lip_bot",
|
|
loc=Cq.Location((0, 0, -dh)) * loc_rotate)
|
|
)
|
|
return result
|
|
|
|
@assembly()
|
|
def assembly(self, deflection: float = 0) -> Cq.Assembly:
|
|
directrix = self.directrix_id
|
|
mat = Material.RESIN_TRANSPERENT
|
|
mat_spring = Material.STEEL_SPRING
|
|
result = (
|
|
Cq.Assembly()
|
|
.addS(self.child(), name="child",
|
|
role=Role.CHILD, material=mat)
|
|
.constrain("child/core", "Fixed")
|
|
.addS(self.torsion_joint.spring.generate(deflection=-deflection), name="spring_top",
|
|
role=Role.DAMPING, material=mat_spring)
|
|
.addS(self.parent_top(),
|
|
name="parent_top",
|
|
role=Role.PARENT, material=mat)
|
|
.addS(self.torsion_joint.spring.generate(deflection=deflection), name="spring_bot",
|
|
role=Role.DAMPING, material=mat_spring)
|
|
.addS(self.parent_bot(),
|
|
name="parent_bot",
|
|
role=Role.PARENT, material=mat)
|
|
)
|
|
TorsionJoint.add_constraints(
|
|
result,
|
|
rider="child/rider_top",
|
|
track="parent_top/track",
|
|
spring="spring_top",
|
|
directrix=directrix)
|
|
TorsionJoint.add_constraints(
|
|
result,
|
|
rider="child/rider_bot",
|
|
track="parent_bot/track",
|
|
spring="spring_bot",
|
|
directrix=directrix)
|
|
return result.solve()
|
|
|
|
|
|
@dataclass
|
|
class Beam:
|
|
"""
|
|
A I-shaped spine with two feet
|
|
"""
|
|
|
|
foot_length: float = 40.0
|
|
foot_width: float = 20.0
|
|
foot_height: float = 5.0
|
|
spine_thickness: float = 4.0
|
|
spine_length: float = 10.0
|
|
total_height: float = 50.0
|
|
|
|
hole_diam: float = 6.0
|
|
# distance between the centres of the two holes
|
|
hole_dist: float = 24.0
|
|
|
|
def __post_init__(self):
|
|
assert self.spine_height > 0
|
|
assert self.hole_diam + self.hole_dist < self.foot_length
|
|
assert self.hole_dist - self.hole_diam >= self.spine_length
|
|
|
|
@property
|
|
def spine_height(self):
|
|
return self.total_height - self.foot_height * 2
|
|
|
|
def foot(self) -> Cq.Workplane:
|
|
"""
|
|
just one foot
|
|
"""
|
|
dx = self.hole_dist / 2
|
|
result = (
|
|
Cq.Workplane('XZ')
|
|
.box(self.foot_length, self.foot_width, self.foot_height,
|
|
centered=(True, True, False))
|
|
.faces(">Y")
|
|
.workplane()
|
|
.pushPoints([(dx, 0), (-dx, 0)])
|
|
.hole(self.hole_diam)
|
|
)
|
|
plane = result.faces(">Y").workplane()
|
|
plane.moveTo(dx, 0).tagPlane("conn1")
|
|
plane.moveTo(-dx, 0).tagPlane("conn0")
|
|
return result
|
|
|
|
def generate(self, flip: bool = False) -> Cq.Assembly:
|
|
beam = (
|
|
Cq.Workplane('XZ')
|
|
.box(self.spine_length, self.spine_thickness, self.spine_height)
|
|
)
|
|
h = self.spine_height / 2 + self.foot_height
|
|
|
|
tag_p, tag_n = "top", "bot"
|
|
if flip:
|
|
tag_p, tag_n = tag_n, tag_p
|
|
result = (
|
|
Cq.Assembly()
|
|
.add(beam, name="beam")
|
|
.add(self.foot(), name=tag_p,
|
|
loc=Cq.Location((0, h, 0)))
|
|
.add(self.foot(), name=tag_n,
|
|
loc=Cq.Location((0, -h, 0), (1, 0, 0), 180))
|
|
)
|
|
return result
|
|
|
|
|
|
@dataclass
|
|
class DiskJoint(Model):
|
|
"""
|
|
Sandwiched disk joint for the wrist and elbow
|
|
|
|
We embed a spring inside the joint, with one leg in the disk and one leg in
|
|
the housing. This provides torsion resistance.
|
|
"""
|
|
spring: TorsionSpring = field(default_factory=lambda: TorsionSpring(
|
|
radius=9 / 2,
|
|
thickness=1.3,
|
|
height=6.5,
|
|
tail_length=45.0,
|
|
right_handed=False,
|
|
))
|
|
|
|
radius_housing: float = 22.0
|
|
radius_disk: float = 20.0
|
|
radius_axle: float = 3.0
|
|
|
|
housing_thickness: float = 4.0
|
|
disk_thickness: float = 7.0
|
|
|
|
# Amount by which the wall carves in
|
|
wall_inset: float = 2.0
|
|
# Height of the spring hole; if you make it too short the spring can't enter
|
|
spring_tail_hole_height: float = 2.0
|
|
|
|
# Spring angle at 0 degrees of movement
|
|
spring_angle_at_0: float = 90.0
|
|
spring_slot_offset: float = 5.0
|
|
|
|
# Angular span of movement
|
|
movement_angle: float = 120.0
|
|
# Angular span of tongue on disk
|
|
tongue_span: float = 30.0
|
|
tongue_length: float = 10.0
|
|
|
|
generate_inner_wall: bool = False
|
|
|
|
|
|
def __post_init__(self):
|
|
super().__init__(name="disk-joint")
|
|
assert self.radius_housing > self.radius_disk > self.radius_axle
|
|
assert self.spring.height < self.housing_thickness + self.disk_thickness
|
|
|
|
assert self.housing_upper_carve_offset > 0
|
|
assert self.spring_tail_hole_height > self.spring.thickness
|
|
|
|
@property
|
|
def neutral_movement_angle(self) -> Optional[float]:
|
|
a = self.spring.angle_neutral - self.spring_angle_at_0
|
|
if 0 <= a and a <= self.movement_angle:
|
|
return a
|
|
return None
|
|
|
|
@property
|
|
def total_thickness(self) -> float:
|
|
return self.housing_thickness * 2 + self.disk_thickness
|
|
@property
|
|
def disk_bot_thickness(self) -> float:
|
|
"""
|
|
Pads the bottom of the disk up to spring height
|
|
"""
|
|
return max(0, self.disk_thickness + self.spring.thickness - self.spring.height)
|
|
|
|
@property
|
|
def opening_span(self) -> float:
|
|
return self.movement_angle + self.tongue_span
|
|
|
|
@property
|
|
def housing_upper_carve_offset(self) -> float:
|
|
"""
|
|
Distance between the spring track and the outside of the upper housing
|
|
"""
|
|
return self.spring_tail_hole_height + (self.disk_thickness - self.disk_bot_thickness) - self.spring.height
|
|
|
|
@property
|
|
def housing_upper_dz(self) -> float:
|
|
"""
|
|
Distance between the default upper housing location and the median line
|
|
"""
|
|
return self.total_thickness / 2 - self.housing_thickness
|
|
|
|
def _disk_cut(self) -> Cq.Workplane:
|
|
return (
|
|
Cq.Solid.makeBox(
|
|
length=self.spring.tail_length,
|
|
width=self.spring.thickness,
|
|
height=self.spring.height-self.disk_bot_thickness,
|
|
)
|
|
.located(Cq.Location((0, self.spring.radius_inner, self.disk_bot_thickness)))
|
|
.rotate((0, 0, 0), (0, 0, 1), self.spring_slot_offset)
|
|
)
|
|
|
|
@target(name="disk")
|
|
def disk(self) -> Cq.Workplane:
|
|
radius_tongue = self.radius_disk + self.tongue_length
|
|
tongue = (
|
|
Cq.Solid.makeCylinder(
|
|
height=self.disk_thickness,
|
|
radius=radius_tongue,
|
|
angleDegrees=self.tongue_span,
|
|
).cut(Cq.Solid.makeCylinder(
|
|
height=self.disk_thickness,
|
|
radius=self.radius_disk,
|
|
))
|
|
)
|
|
result = (
|
|
Cq.Workplane('XY')
|
|
.cylinder(
|
|
height=self.disk_thickness,
|
|
radius=self.radius_disk,
|
|
centered=(True, True, False)
|
|
)
|
|
.union(tongue, tol=TOL)
|
|
.copyWorkplane(Cq.Workplane('XY'))
|
|
.cylinder(
|
|
height=self.disk_thickness,
|
|
radius=self.spring.radius,
|
|
centered=(True, True, False),
|
|
combine='cut',
|
|
)
|
|
.cut(self._disk_cut())
|
|
)
|
|
plane = result.copyWorkplane(Cq.Workplane('XY'))
|
|
theta = math.radians(self.spring_slot_offset)
|
|
plane.tagPlane("dir", direction=(math.cos(theta), math.sin(theta), 0))
|
|
plane.workplane(offset=self.disk_thickness).tagPlane("mate_top")
|
|
plane.workplane(offset=self.disk_bot_thickness).tagPlane("mate_spring")
|
|
result.copyWorkplane(Cq.Workplane('YX')).tagPlane("mate_bot")
|
|
|
|
return result
|
|
|
|
def wall(self) -> Cq.Compound:
|
|
height = self.disk_thickness + self.wall_inset
|
|
wall = Cq.Solid.makeCylinder(
|
|
radius=self.radius_housing,
|
|
height=height,
|
|
angleDegrees=360 - self.opening_span,
|
|
).cut(Cq.Solid.makeCylinder(
|
|
radius=self.radius_disk,
|
|
height=height,
|
|
)).rotate((0, 0, 0), (0, 0, 1), self.opening_span)
|
|
return wall
|
|
|
|
@target(name="housing-lower")
|
|
def housing_lower(self) -> Cq.Workplane:
|
|
result = (
|
|
Cq.Workplane('XY')
|
|
.cylinder(
|
|
radius=self.radius_housing,
|
|
height=self.housing_thickness,
|
|
centered=(True, True, False),
|
|
)
|
|
.cut(Cq.Solid.makeCylinder(
|
|
radius=self.radius_axle,
|
|
height=self.housing_thickness,
|
|
))
|
|
)
|
|
result.faces(">Z").tag("mate")
|
|
result.faces(">Z").workplane().tagPlane("dirX", direction="+X")
|
|
result = result.cut(
|
|
self
|
|
.wall()
|
|
.located(Cq.Location((0, 0, self.housing_thickness - self.wall_inset)))
|
|
#.rotate((0, 0, 0), (1, 0, 0), 180)
|
|
#.located(Cq.Location((0, 0, self.disk_thickness + self.housing_thickness)))
|
|
)
|
|
return result
|
|
|
|
@target(name="housing-upper")
|
|
def housing_upper(self) -> Cq.Workplane:
|
|
carve_angle = -(self.spring_angle_at_0 - self.spring_slot_offset)
|
|
carve = (
|
|
Cq.Solid.makeCylinder(
|
|
radius=self.spring.radius,
|
|
height=self.spring_tail_hole_height,
|
|
).fuse(Cq.Solid.makeBox(
|
|
length=self.spring.tail_length,
|
|
width=self.spring.thickness,
|
|
height=self.spring_tail_hole_height,
|
|
).located(Cq.Location((0, -self.spring.radius, 0))))
|
|
).rotate((0, 0, 0), (0, 0, 1), carve_angle)
|
|
result = (
|
|
Cq.Workplane('XY')
|
|
.cylinder(
|
|
radius=self.radius_housing,
|
|
height=self.housing_thickness,
|
|
centered=(True, True, False),
|
|
)
|
|
)
|
|
theta = math.radians(carve_angle)
|
|
result.faces("<Z").tag("mate")
|
|
p_xy = result.copyWorkplane(Cq.Workplane('XY'))
|
|
p_xy.tagPlane("dirX", direction="+X")
|
|
p_xy.tagPlane("dir", direction=(math.cos(theta), math.sin(theta), 0))
|
|
result = result.faces(">Z").hole(self.radius_axle * 2)
|
|
|
|
# tube which holds the spring interior
|
|
if self.generate_inner_wall:
|
|
tube = (
|
|
Cq.Solid.makeCylinder(
|
|
radius=self.radius_spring_internal,
|
|
height=self.disk_thickness + self.housing_thickness,
|
|
).cut(Cq.Solid.makeCylinder(
|
|
radius=self.radius_axle,
|
|
height=self.disk_thickness + self.housing_thickness,
|
|
))
|
|
)
|
|
result = result.union(tube)
|
|
wall = (
|
|
self.wall()
|
|
.located(Cq.Location((0, 0, -self.disk_thickness-self.wall_inset)))
|
|
)
|
|
result = (
|
|
result
|
|
.union(wall, tol=TOL)
|
|
#.cut(carve)
|
|
.cut(carve.located(Cq.Location((0, 0, -self.housing_upper_carve_offset))))
|
|
)
|
|
return result.clean()
|
|
|
|
def add_constraints(self,
|
|
assembly: Cq.Assembly,
|
|
housing_lower: str,
|
|
housing_upper: str,
|
|
disk: str,
|
|
angle: float = 0.0,
|
|
) -> Cq.Assembly:
|
|
assert 0 <= angle <= self.movement_angle
|
|
deflection = angle - self.neutral_movement_angle
|
|
spring_name = disk.replace("/", "__Z") + "_spring"
|
|
(
|
|
assembly
|
|
.addS(
|
|
self.spring.generate(deflection=-deflection),
|
|
name=spring_name,
|
|
role=Role.DAMPING,
|
|
material=Material.STEEL_SPRING)
|
|
.constrain(f"{disk}?mate_bot", f"{housing_lower}?mate", "Plane")
|
|
.constrain(f"{disk}?mate_top", f"{housing_upper}?mate", "Plane")
|
|
.constrain(f"{housing_lower}?dirX", f"{housing_upper}?dirX", "Axis", param=0)
|
|
.constrain(f"{housing_upper}?dir", f"{spring_name}?dir_top", "Axis", param=0)
|
|
.constrain(f"{spring_name}?dir_bot", f"{disk}?dir", "Axis", param=0)
|
|
.constrain(f"{disk}?mate_spring", f"{spring_name}?bot", "Plane")
|
|
#.constrain(f"{housing_lower}?dirX", f"{housing_upper}?dir", "Axis", param=0)
|
|
#.constrain(f"{housing_lower}?dirX", f"{disk}?dir", "Axis", param=angle)
|
|
#.constrain(f"{housing_lower}?dirY", f"{disk}?dir", "Axis", param=angle - 90)
|
|
)
|
|
return (
|
|
assembly
|
|
)
|
|
|
|
|
|
def assembly(self, angle: Optional[float] = 0) -> Cq.Assembly:
|
|
if angle is None:
|
|
angle = self.neutral_movement_angle
|
|
if angle is None:
|
|
angle = 0
|
|
else:
|
|
assert 0 <= angle <= self.movement_angle
|
|
result = (
|
|
Cq.Assembly()
|
|
.addS(self.disk(), name="disk", role=Role.CHILD)
|
|
.addS(self.housing_lower(), name="housing_lower", role=Role.PARENT)
|
|
.addS(self.housing_upper(), name="housing_upper", role=Role.CASING)
|
|
.constrain("housing_lower", "Fixed")
|
|
)
|
|
result = self.add_constraints(
|
|
result,
|
|
housing_lower="housing_lower",
|
|
housing_upper="housing_upper",
|
|
disk="disk",
|
|
angle=angle,
|
|
)
|
|
return result.solve()
|
|
|
|
|
|
@dataclass(kw_only=True)
|
|
class ElbowJoint(Model):
|
|
"""
|
|
Creates the elbow and wrist joints.
|
|
|
|
This consists of a disk joint, where each side of the joint has mounting
|
|
holes for connection to the exoskeleton. Each side 2 mounting feet on the
|
|
top and bottom, and each foot has 2 holes.
|
|
|
|
On the parent side, additional bolts are needed to clamp the two sides of
|
|
the housing together.
|
|
"""
|
|
|
|
disk_joint: DiskJoint = field(default_factory=lambda: DiskJoint(
|
|
movement_angle=60,
|
|
))
|
|
|
|
# Distance between the child/parent arm to the centre
|
|
child_arm_radius: float = 40.0
|
|
parent_arm_radius: float = 40.0
|
|
|
|
lip_thickness: float = 5.0
|
|
lip_length: float = 60.0
|
|
hole_pos: list[float] = field(default_factory=lambda: [15, 25])
|
|
parent_arm_width: float = 10.0
|
|
# Angle of the beginning of the parent arm
|
|
parent_arm_angle: float = 180.0
|
|
|
|
# Size of the mounting holes
|
|
hole_diam: float = 6.0
|
|
|
|
material: Material = Material.RESIN_TRANSPERENT
|
|
|
|
angle_neutral: float = 30.0
|
|
|
|
def __post_init__(self):
|
|
assert self.child_arm_radius > self.disk_joint.radius_housing
|
|
assert self.parent_arm_radius > self.disk_joint.radius_housing
|
|
self.disk_joint.tongue_length = self.child_arm_radius - self.disk_joint.radius_disk - self.lip_thickness / 2
|
|
|
|
def parent_arm_loc(self) -> Cq.Location:
|
|
"""
|
|
2d Location of the centre of the arm surface on the parent side, assuming
|
|
axle is at position 0, and parent direction is -X
|
|
"""
|
|
return Cq.Location.from2d(-self.parent_arm_radius, 0, 0)
|
|
def child_arm_loc(self, flip: bool = False) -> Cq.Location:
|
|
"""
|
|
2d Location of the centre of the arm surface on the child side, assuming
|
|
axle is at position 0, and parent direction is -X
|
|
|
|
Set `flip=True` to indicate that the joint is supposed to be installed upside down
|
|
"""
|
|
result = Cq.Location.rot2d(self.angle_neutral) * Cq.Location.from2d(self.child_arm_radius, 0, 180)
|
|
return result.flip_y() if flip else result
|
|
|
|
def lip(self) -> Cq.Workplane:
|
|
holes = [
|
|
h
|
|
for i, x in enumerate(self.hole_pos)
|
|
for h in [
|
|
Hole(x=x, tag=f"conn_top{i}"),
|
|
Hole(x=-x, tag=f"conn_bot{i}")
|
|
]
|
|
]
|
|
mbox = MountingBox(
|
|
length=self.lip_length,
|
|
width=self.disk_joint.total_thickness,
|
|
thickness=self.lip_thickness,
|
|
holes=holes,
|
|
hole_diam=self.hole_diam,
|
|
centred=(True, True),
|
|
generate_side_tags=False,
|
|
)
|
|
return mbox.generate()
|
|
|
|
@target(name="child")
|
|
def child_joint(self) -> Cq.Assembly:
|
|
angle = -self.disk_joint.tongue_span / 2
|
|
dz = self.disk_joint.disk_thickness / 2
|
|
# We need to ensure the disk is on the "other" side so
|
|
flip_x = Cq.Location((0, 0, 0), (1, 0, 0), 180)
|
|
flip_z = Cq.Location((0, 0, 0), (0, 0, 1), 180)
|
|
lip_dz = self.lip_thickness
|
|
loc_lip = (
|
|
Cq.Location((0, 0, 0), (0, 1, 0), 180) *
|
|
Cq.Location((-lip_dz, 0, 0), (1, 0, 0), 90) *
|
|
Cq.Location((0, 0, 0), (0, 1, 0), 90)
|
|
)
|
|
loc_disk = flip_x * flip_z * Cq.Location((-self.child_arm_radius, 0, -dz), (0, 0, 1), angle)
|
|
loc_cut_rel = Cq.Location((0, self.disk_joint.spring.radius_inner, -self.disk_joint.disk_bot_thickness))
|
|
disk_cut = self.disk_joint._disk_cut().located(
|
|
loc_lip.inverse * loc_cut_rel * loc_disk)
|
|
result = (
|
|
Cq.Assembly()
|
|
.add(self.lip().cut(disk_cut), name="lip", loc=loc_lip)
|
|
.add(self.disk_joint.disk(), name="disk", loc=loc_disk)
|
|
)
|
|
return result
|
|
|
|
@target(name="parent-lower")
|
|
def parent_joint_lower(self) -> Cq.Workplane:
|
|
return self.disk_joint.housing_lower()
|
|
|
|
@target(name="parent-upper")
|
|
def parent_joint_upper(self):
|
|
axial_offset = Cq.Location((self.parent_arm_radius, 0, 0))
|
|
housing_dz = self.disk_joint.housing_upper_dz
|
|
conn_h = self.disk_joint.total_thickness
|
|
conn_w = self.parent_arm_width
|
|
connector = (
|
|
Cq.Solid.makeBox(
|
|
length=self.parent_arm_radius,
|
|
width=conn_w,
|
|
height=conn_h,
|
|
).located(Cq.Location((0, -conn_w/2, 0)))
|
|
#Cq.Solid.makeCylinder(
|
|
# height=conn_h,
|
|
# radius=self.parent_arm_radius - self.lip_thickness / 2,
|
|
# angleDegrees=self.parent_arm_span)
|
|
.cut(Cq.Solid.makeCylinder(
|
|
height=conn_h,
|
|
radius=self.disk_joint.radius_housing,
|
|
))
|
|
.located(Cq.Location((0, 0, -conn_h / 2)))
|
|
.rotate((0,0,0), (0,0,1), 180)
|
|
#.rotate((0,0,0), (0,0,1), 180-self.parent_arm_span / 2)
|
|
)
|
|
housing = self.disk_joint.housing_upper()
|
|
housing_loc = Cq.Location(
|
|
(0, 0, housing_dz),
|
|
(0, 0, 1),
|
|
-self.disk_joint.tongue_span / 2 + self.angle_neutral
|
|
)
|
|
lip_dz = self.lip_thickness
|
|
result = (
|
|
Cq.Assembly()
|
|
.add(self.lip(), name="lip", loc=
|
|
Cq.Location((0, 0, 0), (0, 1, 0), 180) *
|
|
Cq.Location((-lip_dz, 0, 0), (1, 0, 0), 90) *
|
|
Cq.Location((0, 0, 0), (0, 1, 0), 90))
|
|
.add(housing, name="housing",
|
|
loc=axial_offset * housing_loc)
|
|
.add(connector, name="connector",
|
|
loc=axial_offset)
|
|
#.constrain("housing", "Fixed")
|
|
#.constrain("connector", "Fixed")
|
|
#.solve()
|
|
)
|
|
return result
|
|
|
|
@assembly()
|
|
def assembly(self, angle: float = 0) -> Cq.Assembly:
|
|
result = (
|
|
Cq.Assembly()
|
|
.addS(self.child_joint(), name="child",
|
|
role=Role.CHILD, material=self.material)
|
|
.addS(self.parent_joint_lower(), name="parent_lower",
|
|
role=Role.CASING, material=self.material)
|
|
.addS(self.parent_joint_upper(), name="parent_upper",
|
|
role=Role.PARENT, material=self.material)
|
|
#.constrain("child/disk?mate_bot", "Fixed")
|
|
)
|
|
result = self.disk_joint.add_constraints(
|
|
result,
|
|
housing_lower="parent_lower",
|
|
housing_upper="parent_upper/housing",
|
|
disk="child/disk",
|
|
angle=angle,
|
|
)
|
|
return result.solve()
|
|
|
|
if __name__ == '__main__':
|
|
p = ShoulderJoint()
|
|
p.build_all()
|
|
p = DiskJoint()
|
|
p.build_all()
|