nhf/touhou/houjuu_nue/wing.py

@@ -59,6 +59,7 @@ class WingProfile(Model):
     # strength
     spacer_thickness: float = 25.4 / 4
     rod_width: float = 10.0
+    panel_s0_inner_trunc = 0.05
 
     light_strip: LightStrip = LightStrip()
 
@@ -186,7 +187,7 @@ class WingProfile(Model):
                 ]
             ]
         )
-    def inner_profile_s0(self) -> Cq.Edge:
+    def inner_profile_s0(self, trunc: float=0.0) -> Cq.Edge:
         """
         The inner boundary of s0
         """
@@ -203,9 +204,21 @@ class WingProfile(Model):
             (-self.base_width + dx1, dy1),
             (-self.base_width, 0),
         ]
-        return Cq.Edge.makeBezier(
+        bezier = Cq.Edge.makeBezier(
             [Cq.Vector(x, y) for x, y in points]
         )
+        if trunc == 0.0:
+            return bezier
+
+        tip = bezier.positionAt(d=trunc, mode='parameter')
+        tangent = bezier.tangentAt(locationParam=trunc, mode='parameter')
+        points = [
+            tip,
+            tip + tangent,
+            Cq.Vector(-self.base_width + dx1, dy1),
+            Cq.Vector(-self.base_width, 0),
+        ]
+        return Cq.Edge.makeBezier(points)
 
 
     @property
@@ -266,7 +279,7 @@ class WingProfile(Model):
         return result
     def inner_shell_s0(self) -> Cq.Workplane:
         t = self.panel_thickness_s0
-        profile = self.inner_profile_s0()
+        profile = self.inner_profile_s0(trunc=self.panel_s0_inner_trunc)
         result = (
             Cq.Workplane('XZ')
             .moveTo(-t, 0)
@@ -291,7 +304,7 @@ class WingProfile(Model):
         """
         This part should be laser cut and then bent on a falsework to create the required shape.
         """
-        length = self.inner_profile_s0().Length()
+        length = self.inner_profile_s0(trunc=self.panel_s0_inner_trunc).Length()
         height = self.root_height + self.panel_thickness_s0 * 2
         return Cq.Sketch().rect(length, height)