Cosplay/nhf/touhou/houjuu_nue/joints.py

639 lines
22 KiB
Python

from dataclasses import dataclass, field
from typing import Optional, Tuple
import cadquery as Cq
from nhf import Role
from nhf.build import Model, target, assembly
import nhf.parts.springs as springs
from nhf.parts.joints import TorsionJoint
import nhf.utils
TOL = 1e-6
@dataclass
class ShoulderJoint(Model):
shoulder_height: float = 100.0
torsion_joint: TorsionJoint = field(default_factory=lambda: TorsionJoint(
radius_track=18,
radius_rider=18,
groove_radius_outer=16,
groove_radius_inner=13,
track_disk_height=5.0,
rider_disk_height=5.0,
# M8 Axle
radius_axle=3.0,
# inner diameter = 9
radius_spring=9/2 + 1.2,
spring_thickness=1.3,
spring_height=7.5,
))
# Two holes on each side (top and bottom) are used to attach the shoulder
# joint. This governs the distance between these two holes
attach_dist: float = 25
attach_diam: float = 8
@target(name="shoulder-joint/parent")
def parent(self,
wing_root_wall_thickness: float = 5.0) -> Cq.Workplane:
joint = self.torsion_joint
# Thickness of the lip connecting this joint to the wing root
lip_thickness = 10
lip_width = 25
lip_guard_ext = 40
lip_guard_height = wing_root_wall_thickness + lip_thickness
assert lip_guard_ext > joint.radius_track
lip_guard = (
Cq.Solid.makeBox(lip_guard_ext, lip_width, lip_guard_height)
.located(Cq.Location((0, -lip_width/2 , 0)))
.cut(Cq.Solid.makeCylinder(joint.radius_track, lip_guard_height))
)
result = (
joint.track()
.union(lip_guard, tol=1e-6)
# Extrude the handle
.copyWorkplane(Cq.Workplane(
'YZ', origin=Cq.Vector((88, 0, wing_root_wall_thickness))))
.rect(lip_width, lip_thickness, centered=(True, False))
.extrude("next")
# Connector holes on the lip
.copyWorkplane(Cq.Workplane(
'YX', origin=Cq.Vector((57, 0, wing_root_wall_thickness))))
.hole(self.attach_diam)
.moveTo(0, self.attach_dist)
.hole(self.attach_diam)
)
result.moveTo(0, 0).tagPlane('conn0')
result.moveTo(0, self.attach_dist).tagPlane('conn1')
return result
@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.shoulder_height - 2 * joint.total_height + 2 * joint.rider_disk_height
@target(name="shoulder-joint/child")
def child(self,
lip_height: float = 20.0,
hole_dist: float = 10.0,
spacer_hole_diam: float = 8.0) -> Cq.Assembly:
"""
Creates the top/bottom shoulder child joint
"""
joint = self.torsion_joint
# Half of the height of the bridging cylinder
dh = self.shoulder_height / 2 - joint.total_height
core_start_angle = 30
core_end_angle1 = 90
core_end_angle2 = 180
core_thickness = 2
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(joint.radius_rider - core_thickness, 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(joint.radius_rider - core_thickness, 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))
)
# Create the upper and lower lips
lip_thickness = joint.rider_disk_height
lip_ext = 40 + joint.radius_rider
assert lip_height / 2 <= joint.radius_rider
lip = (
Cq.Workplane('XY')
.box(lip_ext, lip_height, lip_thickness,
centered=(False, True, False))
.copyWorkplane(Cq.Workplane('XY'))
.cylinder(radius=joint.radius_rider, height=lip_thickness,
centered=(True, True, False),
combine='cut')
.faces(">Z")
.workplane()
)
hole_x = lip_ext - hole_dist / 2
for i in range(2):
x = hole_x - i * hole_dist
lip = lip.moveTo(x, 0).hole(spacer_hole_diam)
for i in range(2):
x = hole_x - i * hole_dist
(
lip
.moveTo(x, 0)
.tagPlane(f"conn{1 - i}")
)
loc_rotate = Cq.Location((0, 0, 0), (1, 0, 0), 180)
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=Cq.Location((0, 0, dh), (0, 0, 1), -90))
.add(joint.rider(rider_slot_begin=180), name="rider_bot",
loc=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,
wing_root_wall_thickness: float = 5.0,
lip_height: float = 5.0,
hole_dist: float = 10.0,
spacer_hole_diam: float = 8.0
) -> Cq.Assembly:
directrix = 0
result = (
Cq.Assembly()
.add(self.child(lip_height=lip_height,
hole_dist=hole_dist,
spacer_hole_diam=spacer_hole_diam),
name="child",
color=Role.CHILD.color)
.constrain("child/core", "Fixed")
.add(self.torsion_joint.spring(), name="spring_top",
color=Role.DAMPING.color)
.add(self.parent(wing_root_wall_thickness),
name="parent_top",
color=Role.PARENT.color)
.add(self.torsion_joint.spring(), name="spring_bot",
color=Role.DAMPING.color)
.add(self.parent(wing_root_wall_thickness),
name="parent_bot",
color=Role.PARENT.color)
)
TorsionJoint.add_constraints(result,
rider="child/rider_top",
track="parent_top",
spring="spring_top",
directrix=directrix)
TorsionJoint.add_constraints(result,
rider="child/rider_bot",
track="parent_bot",
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 = 8.0
# 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 beam(self) -> Cq.Assembly:
beam = (
Cq.Workplane('XZ')
.box(self.spine_length, self.spine_thickness, self.spine_height)
)
h = self.spine_height / 2 + self.foot_height
result = (
Cq.Assembly()
.add(beam, name="beam")
.add(self.foot(), name="top",
loc=Cq.Location((0, h, 0)))
.add(self.foot(), name="bot",
loc=Cq.Location((0, -h, 0), (1, 0, 0), 180))
)
return result
@dataclass
class DiskJoint(Model):
"""
Sandwiched disk joint for the wrist and elbow
"""
radius_housing: float = 22.0
radius_disk: float = 20.0
radius_spring: float = 9 / 2
radius_axle: float = 3.0
housing_thickness: float = 5.0
disk_thickness: float = 5.0
# Gap between disk and the housing
#disk_thickness_gap: float = 0.1
spring_thickness: float = 1.3
spring_height: float = 6.5
spring_tail_length: float = 45.0
# Spring angle at 0 degrees of movement
spring_angle: float = 30.0
# Angle at which the spring exerts no torque
spring_angle_neutral: float = 90.0
spring_angle_shift: float = 30
wall_inset: float = 2.0
# 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.housing_thickness > self.wall_inset
assert self.radius_housing > self.radius_disk
assert self.radius_disk > self.radius_axle
assert self.housing_upper_carve_offset > 0
def spring(self):
return springs.torsion_spring(
radius=self.radius_spring,
height=self.spring_height,
thickness=self.spring_thickness,
tail_length=self.spring_tail_length,
right_handed=False,
)
@property
def neutral_movement_angle(self) -> Optional[float]:
a = self.spring_angle_neutral - self.spring_angle
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 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.housing_thickness + self.disk_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
@property
def radius_spring_internal(self):
return self.radius_spring - self.spring_thickness
@target(name="disk")
def disk(self) -> Cq.Workplane:
cut = (
Cq.Solid.makeBox(
length=self.spring_tail_length,
width=self.spring_thickness,
height=self.disk_thickness,
)
.located(Cq.Location((0, self.radius_spring_internal, 0)))
.rotate((0, 0, 0), (0, 0, 1), self.spring_angle_shift)
)
result = (
Cq.Workplane('XY')
.cylinder(
height=self.disk_thickness,
radius=self.radius_disk,
centered=(True, True, False)
)
.copyWorkplane(Cq.Workplane('XY'))
.cylinder(
height=self.disk_thickness,
radius=self.radius_spring,
centered=(True, True, False),
combine='cut',
)
.cut(cut)
)
plane = result.copyWorkplane(Cq.Workplane('XY'))
plane.tagPlane("dir", direction="+X")
plane.workplane(offset=self.disk_thickness).tagPlane("mate_top")
result.copyWorkplane(Cq.Workplane('YX')).tagPlane("mate_bot")
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 = result.union(tongue, tol=TOL)
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")
# two directional vectors are required to make the angle constrain
# unambiguous
result.faces(">Z").workplane().tagPlane("dirY", direction="+Y")
result = result.cut(
self
.wall()
.located(Cq.Location((0, 0, self.disk_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 = (
Cq.Solid.makeCylinder(
radius=self.radius_spring,
height=self.housing_thickness
).fuse(Cq.Solid.makeBox(
length=self.spring_tail_length,
width=self.spring_thickness,
height=self.housing_thickness
).located(Cq.Location((0, -self.radius_spring, 0))))
).rotate((0, 0, 0), (0, 0, 1), self.spring_angle - self.spring_angle_shift)
result = (
Cq.Workplane('XY')
.cylinder(
radius=self.radius_housing,
height=self.housing_thickness,
centered=(True, True, False),
)
)
result.faces("<Z").tag("mate")
result.copyWorkplane(Cq.Workplane('XY')).tagPlane("dir", direction="-X")
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
.cut(carve.located(Cq.Location((0, 0, -self.housing_upper_carve_offset))))
.union(wall, tol=TOL)
)
return result
def add_constraints(self,
assembly: Cq.Assembly,
housing_lower: str,
housing_upper: str,
disk: str,
angle: float,
) -> Cq.Assembly:
(
assembly
.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}?dir", "Axis")
.constrain(f"{housing_lower}?dirX", f"{disk}?dir", "Axis", param=angle)
.constrain(f"{housing_lower}?dirY", f"{disk}?dir", "Axis", param=angle - 90)
)
def assembly(self, angle: Optional[float] = 0) -> Cq.Assembly:
if angle is None:
angle = self.movement_angle
if angle is None:
angle = 0
else:
assert 0 <= angle <= self.movement_angle
result = (
Cq.Assembly()
.add(self.disk(), name="disk", color=Role.CHILD.color)
.add(self.housing_lower(), name="housing_lower", color=Role.PARENT.color)
.add(self.housing_upper(), name="housing_upper", color=Role.CASING.color)
.constrain("housing_lower", "Fixed")
)
self.add_constraints(
result,
housing_lower="housing_lower",
housing_upper="housing_upper",
disk="disk",
angle=angle,
)
return result.solve()
@dataclass
class ElbowJoint:
"""
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
child_beam: Beam = field(default_factory=lambda: Beam())
parent_beam: Beam = field(default_factory=lambda: Beam(
spine_thickness=8.0,
))
parent_arm_span: float = 40.0
# Angle of the beginning of the parent arm
parent_arm_angle: float = 180.0
parent_binding_hole_radius: float = 30.0
# Size of the mounting holes
hole_diam: float = 8.0
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
assert self.disk_joint.movement_angle < self.parent_arm_angle < 360 - self.parent_arm_span
assert self.parent_binding_hole_radius - self.hole_diam / 2 > self.disk_joint.radius_housing
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 = Cq.Location((0, 0, 0), (0, 0, 1), 180)
result = (
self.child_beam.beam()
.add(self.disk_joint.disk(), name="disk",
loc=flip * Cq.Location((-self.child_arm_radius, 0, -dz), (0, 0, 1), angle))
.constrain("disk", "Fixed")
.constrain("top", "Fixed")
.constrain("bot", "Fixed")
.solve()
)
return result
def parent_joint_lower(self) -> Cq.Workplane:
return self.disk_joint.housing_lower()
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.parent_beam.spine_thickness
connector = (
Cq.Solid.makeCylinder(
height=conn_h,
radius=self.parent_arm_radius,
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-self.parent_arm_span / 2)
)
housing = self.disk_joint.housing_upper()
result = (
self.parent_beam.beam()
.add(housing, name="housing",
loc=axial_offset * Cq.Location((0, 0, housing_dz)))
.add(connector, name="connector",
loc=axial_offset)
.constrain("housing", "Fixed")
.constrain("connector", "Fixed")
.solve()
)
return result
def assembly(self, angle: float = 0) -> Cq.Assembly:
da = self.disk_joint.tongue_span / 2 + 180
result = (
Cq.Assembly()
.add(self.child_joint(), name="child", color=Role.CHILD.color)
.add(self.parent_joint_lower(), name="parent_lower", color=Role.CASING.color)
.add(self.parent_joint_upper(), name="parent_upper", color=Role.PARENT.color)
#.constrain("parent_lower", "Fixed")
)
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()