ENH: Free-Form Fins

rocketpy/__init__.py

@@ -30,6 +30,7 @@
     Components,
     EllipticalFins,
     Fins,
+    FreeFormFins,
     GenericSurface,
     LinearGenericSurface,
     NoseCone,

rocketpy/plots/aero_surface_plots.py

@@ -380,6 +380,73 @@ def draw(self):
         plt.show()
 
 
+class _FreeFormFinsPlots(_FinsPlots):
+    """Class that contains all free form fin plots."""
+
+    # pylint: disable=too-many-statements
+    def draw(self):
+        """Draw the fin shape along with some important information, including
+        the center line, the quarter line and the center of pressure position.
+
+        Returns
+        -------
+        None
+        """
+        # Color cycle [#348ABD, #A60628, #7A68A6, #467821, #D55E00, #CC79A7,
+        # #56B4E9, #009E73, #F0E442, #0072B2]
+
+        # Center of pressure
+        cp_point = [self.aero_surface.cpz, self.aero_surface.Yma]
+
+        # Mean Aerodynamic Chord
+        yma_line = plt.Line2D(
+            (
+                self.aero_surface.mac_lead,
+                self.aero_surface.mac_lead + self.aero_surface.mac_length,
+            ),
+            (self.aero_surface.Yma, self.aero_surface.Yma),
+            color="#467821",
+            linestyle="--",
+            label="Mean Aerodynamic Chord",
+        )
+
+        # Plotting
+        fig = plt.figure(figsize=(7, 4))
+        with plt.style.context("bmh"):
+            ax = fig.add_subplot(111)
+
+        # Fin
+        ax.scatter(
+            self.aero_surface.shape_vec[0],
+            self.aero_surface.shape_vec[1],
+            color="#A60628",
+        )
+        ax.plot(
+            self.aero_surface.shape_vec[0],
+            self.aero_surface.shape_vec[1],
+            color="#A60628",
+        )
+        # line from the last point to the first point
+        ax.plot(
+            [self.aero_surface.shape_vec[0][-1], self.aero_surface.shape_vec[0][0]],
+            [self.aero_surface.shape_vec[1][-1], self.aero_surface.shape_vec[1][0]],
+            color="#A60628",
+        )
+
+        ax.add_line(yma_line)
+        ax.scatter(*cp_point, label="Center of Pressure", color="red", s=100, zorder=10)
+        ax.scatter(*cp_point, facecolors="none", edgecolors="red", s=500, zorder=10)
+
+        # Plot settings
+        ax.set_xlabel("Root chord (m)")
+        ax.set_ylabel("Span (m)")
+        ax.set_title("Free Form Fin Cross Section")
+        ax.legend(bbox_to_anchor=(1.05, 1.0), loc="upper left")
+
+        plt.tight_layout()
+        plt.show()
+
+
 class _TailPlots(_AeroSurfacePlots):
     """Class that contains all tail plots."""
 

rocketpy/prints/aero_surface_prints.py

@@ -183,6 +183,10 @@ class _EllipticalFinsPrints(_FinsPrints):
     """Class that contains all elliptical fins prints."""
 
 
+class _FreeFormFinsPrints(_FinsPrints):
+    """Class that contains all free form fins prints."""
+
+
 class _TailPrints(_AeroSurfacePrints):
     """Class that contains all tail prints."""
 

rocketpy/rocket/__init__.py

@@ -4,6 +4,7 @@
     AirBrakes,
     EllipticalFins,
     Fins,
+    FreeFormFins,
     GenericSurface,
     LinearGenericSurface,
     NoseCone,

rocketpy/rocket/aero_surface/__init__.py

@@ -1,6 +1,11 @@
 from rocketpy.rocket.aero_surface.aero_surface import AeroSurface
 from rocketpy.rocket.aero_surface.air_brakes import AirBrakes
-from rocketpy.rocket.aero_surface.fins import EllipticalFins, Fins, TrapezoidalFins
+from rocketpy.rocket.aero_surface.fins import (
+    EllipticalFins,
+    Fins,
+    FreeFormFins,
+    TrapezoidalFins,
+)
 from rocketpy.rocket.aero_surface.generic_surface import GenericSurface
 from rocketpy.rocket.aero_surface.linear_generic_surface import LinearGenericSurface
 from rocketpy.rocket.aero_surface.nose_cone import NoseCone

rocketpy/rocket/aero_surface/fins/__init__.py

@@ -1,3 +1,4 @@
 from rocketpy.rocket.aero_surface.fins.elliptical_fins import EllipticalFins
 from rocketpy.rocket.aero_surface.fins.fins import Fins
+from rocketpy.rocket.aero_surface.fins.free_form_fins import FreeFormFins
 from rocketpy.rocket.aero_surface.fins.trapezoidal_fins import TrapezoidalFins