feat: Bayonet mount

nhf/parts/handle.py

@@ -5,19 +5,20 @@ from dataclasses import dataclass, field
 from typing import Union, Optional
 import cadquery as Cq
 import nhf.parts.metric_threads as metric_threads
+import nhf.utils
 
 class Mount:
     """
     Describes the internal connection between two cylinders
     """
 
-    def diam_insertion_internal(self):
+    def diam_insertion_internal(self) -> float:
         """
-        Maximum permitted diameter of the internal cavity
+        Diameter of the internal cavity in the insertion
         """
-    def diam_connector_external(self):
+    def diam_connector_external(self) -> float:
         """
-        Maximum permitted diameter of the external size of the insertion
+        Diameter of the external size of the connector
         """
     def external_thread(self, length: float) -> Cq.Shape:
         """
@@ -29,7 +30,7 @@ class Mount:
         """
 
 @dataclass
-class ThreadedJoint(Mount):
+class ThreadedMount(Mount):
 
     pitch: float = 3
 
@@ -37,13 +38,13 @@ class ThreadedJoint(Mount):
     # standard. This determines the wall thickness of the insertion.
     diam_threading: float = 27
 
-    def diam_insertion_internal(self):
+    def diam_insertion_internal(self) -> float:
         r = metric_threads.metric_thread_major_radius(
             self.diam_threading,
             self.pitch,
             internal=True)
         return r * 2
-    def diam_connector_external(self):
+    def diam_connector_external(self) -> float:
         r = metric_threads.metric_thread_minor_radius(
             self.diam_threading,
             self.pitch)
@@ -64,9 +65,94 @@ class ThreadedJoint(Mount):
 @dataclass
 class BayonetMount(Mount):
     """
-    Bayonet type joint
+    Bayonet type connection
     """
-    pass
+    diam_outer: float = 30
+    diam_inner: float = 27
+
+    # Angular span (in degrees) of the slider
+    pin_span: float = 15
+    pin_height: float = 5
+
+    # Angular span (in degrees) of the slot
+    slot_span: float = 90
+
+    # Number of pins equally distributed along a circle
+    n_pin: int = 2
+
+    def __post_init__(self):
+        assert self.diam_outer > self.diam_inner
+        assert self.n_pin * self.slot_span < 360
+        assert self.slot_span > self.pin_span
+
+    def diam_insertion_internal(self) -> float:
+        return self.diam_outer
+    def diam_connector_external(self) -> float:
+        return self.diam_inner
+
+    def external_thread(self, length: float):
+        assert length > self.pin_height
+        pin = (
+            Cq.Workplane('XY')
+            .cylinder(
+                height=self.pin_height,
+                radius=self.diam_outer / 2,
+                angle=self.pin_span,
+                centered=(True, True, False))
+            .copyWorkplane(Cq.Workplane('XY'))
+            .cylinder(
+                height=self.pin_height,
+                radius=self.diam_inner / 2,
+                centered=(True, True, False),
+                combine="cut")
+            .val()
+        )
+        result = (
+            Cq.Workplane('XY')
+            .polarArray(radius=0, startAngle=0, angle=360, count=self.n_pin)
+            .eachpoint(lambda loc: pin.located(loc), combine='a')
+            .clean()
+        )
+        return result
+    def internal_thread(self, length: float):
+        assert length > self.pin_height
+        slot = (
+            Cq.Workplane('XY')
+            .cylinder(
+                height=length,
+                radius=self.diam_outer / 2,
+                angle=self.pin_span,
+                centered=(True, True, False)
+            )
+            .copyWorkplane(Cq.Workplane('XY'))
+            .cylinder(
+                height=self.pin_height,
+                radius=self.diam_outer / 2,
+                angle=self.slot_span,
+                centered=(True, True, False)
+            )
+            .val()
+        )
+        result = (
+            Cq.Workplane('XY')
+            .cylinder(
+                height=length,
+                radius=self.diam_outer / 2,
+                centered=(True, True, False),
+            )
+            .polarArray(radius=0, startAngle=-self.slot_span+self.pin_span, angle=360, count=self.n_pin)
+            .cutEach(lambda loc: slot.located(loc))
+            .clean()
+            .copyWorkplane(Cq.Workplane('XY'))
+            .cylinder(
+                height=length,
+                radius=self.diam_inner / 2,
+                centered=(True, True, False),
+                combine="cut"
+            )
+        )
+        return result
+
 
 @dataclass
 class Handle:
@@ -75,7 +161,7 @@ class Handle:
 
     This assumes the handle segment material does not have threads. Each segment
     attaches to two insertions, which have threads on the inside. A connector
-    has threads on the outside and joints two insertions.
+    has threads on the outside and mounts two insertions.
 
     Note that all the radial sizes are diameters (in mm).
     """
@@ -84,7 +170,7 @@ class Handle:
     diam: float = 38
     diam_inner: float = 33
 
-    joint: Optional[Mount] = field(default_factory=lambda: ThreadedJoint())
+    mount: Optional[Mount] = field(default_factory=lambda: ThreadedMount())
 
     # Internal cavity diameter. This determines the wall thickness of the connector
     diam_connector_internal: float = 18.0
@@ -102,10 +188,10 @@ class Handle:
 
     def __post_init__(self):
         assert self.diam > self.diam_inner, "Material thickness cannot be <= 0"
-        if self.joint:
+        if self.mount:
-            assert self.diam_inner > self.joint.diam_insertion_internal(), "Threading radius is too big"
+            assert self.diam_inner > self.mount.diam_insertion_internal(), "Threading radius is too big"
-            assert self.joint.diam_insertion_internal() > self.joint.diam_connector_external()
+            assert self.mount.diam_insertion_internal() >= self.mount.diam_connector_external()
-            assert self.joint.diam_connector_external() > self.diam_connector_internal, "Internal diameter is too large"
+            assert self.mount.diam_connector_external() > self.diam_connector_internal, "Internal diameter is too large"
         assert self.insertion_length > self.rim_length
 
     def segment(self, length: float):
@@ -123,8 +209,8 @@ class Handle:
 
     def insertion(self, holes=[]):
         """
-        This type of joint is used to connect two handlebar pieces. Each handlebar
+        This type of mount is used to connect two handlebar pieces. Each handlebar
-        piece is a tube which cannot be machined, so the joint connects to the
+        piece is a tube which cannot be machined, so the mount connects to the
         handle by glue.
 
         Tags:
@@ -152,11 +238,12 @@ class Handle:
                 .circle(self.diam / 2)
                 .extrude(self.rim_length)
                 .faces(">Z")
-                .hole(self.joint.diam_insertion_internal())
+                .hole(self.mount.diam_insertion_internal())
             )
         result.faces(">Z").tag("mate")
+        result.copyWorkplane(Cq.Workplane('XY')).tagPlane("dir", "+X")
         if not self.simplify_geometry:
-            thread = self.joint.internal_thread(self.insertion_length).val()
+            thread = self.mount.internal_thread(self.insertion_length).val()
             result = result.union(thread)
         for h in holes:
             cyl = Cq.Solid.makeCylinder(
@@ -188,23 +275,24 @@ class Handle:
                 result
                 .faces(selector)
                 .workplane()
-                .circle(self.joint.diam_connector_external() / 2)
+                .circle(self.mount.diam_connector_external() / 2)
                 .extrude(self.insertion_length)
             )
         if not solid:
             result = result.faces(">Z").hole(self.diam_connector_internal)
         if not self.simplify_geometry:
-            thread = self.joint.external_thread(self.insertion_length).val()
+            thread = self.mount.external_thread(self.insertion_length).val()
             result = (
                 result
                 .union(
                     thread
-                    .located(Cq.Location((0, 0, self.connector_length / 2))))
+                    .located(Cq.Location((0, 0, -self.connector_length))))
                 .union(
                     thread
                     .rotate((0,0,0), (1,0,0), angleDegrees=180)
-                    .located(Cq.Location((0, 0, -self.connector_length / 2))))
+                    .located(Cq.Location((0, 0, self.connector_length))))
             )
+        result.copyWorkplane(Cq.Workplane('XY')).tagPlane("dir", "+X")
         return result
 
     def one_side_connector(self, height=None):
@@ -224,18 +312,19 @@ class Handle:
             result
             .faces(">Z")
             .workplane()
-            .circle(self.joint.diam_connector_external() / 2)
+            .circle(self.mount.diam_connector_external() / 2)
             .extrude(self.insertion_length)
         )
+        result.copyWorkplane(Cq.Workplane('XY')).tagPlane("dir", "+X")
         if not self.simplify_geometry:
-            thread = self.joint.external_thread(self.insertion_length).val()
+            thread = self.mount.external_thread(self.insertion_length).val()
             result = (
                 result
                 .union(
                     thread
                     # Avoids collision in some mating cases
                     .rotate((0,0,0), (1,0,0), angleDegrees=180)
-                    .located(Cq.Location((0, 0, height))))
+                    .located(Cq.Location((0, 0, height + self.insertion_length))))
             )
         return result
 
@@ -246,7 +335,7 @@ class Handle:
         result = (
             Cq.Workplane('XY')
             .cylinder(
-                radius=self.joint.diam_connector_external / 2,
+                radius=self.mount.diam_connector_external / 2,
                 height=length,
                 centered=(True, True, False),
             )
@@ -254,7 +343,7 @@ class Handle:
         result.faces(">Z").tag("mate")
         result.faces("<Z").tag("base")
         if not self.simplify_geometry:
-            thread = self.joint.external_thread(length=length).val()
+            thread = self.mount.external_thread(length=length).val()
             result = (
                 result
                 .union(thread)
@@ -271,6 +360,8 @@ class Handle:
             .add(self.insertion(), name="i2", color=insertion_color)
             .constrain("c?mate1", "i1?mate", "Plane")
             .constrain("c?mate2", "i2?mate", "Plane")
+            .constrain("c?dir", "i1?dir", "Axis")
+            .constrain("c?dir", "i2?dir", "Axis")
             .solve()
         )
         return result
@@ -282,6 +373,7 @@ class Handle:
             .add(self.insertion(), name="i", color=connector_color)
             .add(self.one_side_connector(), name="c", color=insertion_color)
             .constrain("i?mate", "c?mate", "Plane")
+            .constrain("c?dir", "i?dir", "Axis")
             .solve()
         )
         return result

nhf/parts/test.py

@@ -58,25 +58,41 @@ class TestJoints(unittest.TestCase):
 
 class TestHandle(unittest.TestCase):
 
-    def test_handle_collision(self):
+    def test_threaded_collision(self):
-        h = handle.Handle()
+        h = handle.Handle(mount=handle.ThreadedMount())
         assembly = h.connector_insertion_assembly()
         self.assertEqual(pairwise_intersection(assembly), [])
-    def test_handle_assembly(self):
+    def test_threaded_assembly(self):
-        h = handle.Handle()
+        h = handle.Handle(mount=handle.ThreadedMount())
         assembly = h.connector_insertion_assembly()
         bbox = assembly.toCompound().BoundingBox()
         self.assertAlmostEqual(bbox.xlen, h.diam)
         self.assertAlmostEqual(bbox.ylen, h.diam)
-
+    def test_threaded_one_sided_insertion(self):
-    def test_one_sided_insertion(self):
+        h = handle.Handle(mount=handle.ThreadedMount())
-        h = handle.Handle()
         assembly = h.connector_one_side_insertion_assembly()
         bbox = assembly.toCompound().BoundingBox()
         self.assertAlmostEqual(bbox.xlen, h.diam)
         self.assertAlmostEqual(bbox.ylen, h.diam)
         self.assertEqual(pairwise_intersection(assembly), [])
+    def test_bayonet_collision(self):
+        h = handle.Handle(mount=handle.BayonetMount())
+        assembly = h.connector_insertion_assembly()
+        self.assertEqual(pairwise_intersection(assembly), [])
+    def test_bayonet_assembly(self):
+        h = handle.Handle(mount=handle.BayonetMount())
+        assembly = h.connector_insertion_assembly()
+        bbox = assembly.toCompound().BoundingBox()
+        self.assertAlmostEqual(bbox.xlen, h.diam)
+        self.assertAlmostEqual(bbox.ylen, h.diam)
 
+    def test_bayonet_one_sided_insertion(self):
+        h = handle.Handle(mount=handle.BayonetMount())
+        assembly = h.connector_one_side_insertion_assembly()
+        bbox = assembly.toCompound().BoundingBox()
+        self.assertAlmostEqual(bbox.xlen, h.diam)
+        self.assertAlmostEqual(bbox.ylen, h.diam)
+        self.assertEqual(pairwise_intersection(assembly), [])
 
 class TestMetricThreads(unittest.TestCase):
 

nhf/touhou/houjuu_nue/__init__.py

@@ -34,7 +34,7 @@ import cadquery as Cq
 from nhf import Material, Role
 from nhf.build import Model, TargetKind, target, assembly
 from nhf.parts.joints import HirthJoint, TorsionJoint
-from nhf.parts.handle import Handle
+from nhf.parts.handle import Handle, BayonetMount
 import nhf.touhou.houjuu_nue.wing as MW
 import nhf.touhou.houjuu_nue.trident as MT
 import nhf.utils
@@ -129,7 +129,9 @@ class Parameters(Model):
         diam_inner=38-2 * 25.4/8,
         diam_connector_internal=18,
         simplify_geometry=False,
+        mount=BayonetMount(n_pin=3),
     ))
+    trident_terminal_height: float = 60
 
     material_panel: Material = Material.ACRYLIC_TRANSPARENT
     material_bracket: Material = Material.ACRYLIC_TRANSPARENT
@@ -147,6 +149,12 @@ class Parameters(Model):
     @target(name="trident/handle-insertion")
     def handle_insertion(self):
         return self.trident_handle.insertion()
+    @target(name="trident/proto-handle-terminal-connector")
+    def handle_experimental_connector(self):
+        return self.trident_handle.one_side_connector(height=15)
+    @target(name="trident/handle-terminal-connector")
+    def handle_terminal_connector(self):
+        return self.trident_handle.one_side_connector(height=self.trident_terminal_height)
 
 
     def harness_profile(self) -> Cq.Sketch: