ENH: Individual Fin

rocketpy/__init__.py

@@ -28,16 +28,19 @@
     AeroSurface,
     AirBrakes,
     Components,
+    EllipticalFin,
     EllipticalFins,
+    Fin,
     Fins,
+    GenericSurface,
+    LinearGenericSurface,
     NoseCone,
     Parachute,
     RailButtons,
     Rocket,
     Tail,
+    TrapezoidalFin,
     TrapezoidalFins,
-    GenericSurface,
-    LinearGenericSurface,
 )
 from .simulation import Flight, MonteCarlo
 from .stochastic import (

rocketpy/plots/aero_surface_plots.py

@@ -188,6 +188,67 @@ def all(self):
         self.lift()
 
 
+class _FinPlots(_AeroSurfacePlots):
+    """Abstract class that contains all fin plots. This class inherits from the
+    _AeroSurfacePlots class."""
+
+    @abstractmethod
+    def draw(self):
+        pass
+
+    def airfoil(self):
+        """Plots the airfoil information when the fin has an airfoil shape. If
+        the fin does not have an airfoil shape, this method does nothing.
+
+        Returns
+        -------
+        None
+        """
+
+        if self.aero_surface.airfoil:
+            print("Airfoil lift curve:")
+            self.aero_surface.airfoil_cl.plot_1d(force_data=True)
+
+    def roll(self):
+        """Plots the roll parameters of the fin set.
+
+        Returns
+        -------
+        None
+        """
+        print("Roll parameters:")
+        # TODO: lacks a title in the plots
+        self.aero_surface.roll_parameters[0]()
+        self.aero_surface.roll_parameters[1]()
+
+    def lift(self):
+        """Plots the lift coefficient of the aero surface as a function of Mach
+        and the angle of attack. A 3D plot is expected. See the rocketpy.Function
+        class for more information on how this plot is made. Also, this method
+        plots the lift coefficient considering a single fin and the lift
+        coefficient considering all fins.
+
+        Returns
+        -------
+        None
+        """
+        print("Lift coefficient:")
+        self.aero_surface.cl()
+        self.aero_surface.clalpha_single_fin()
+
+    def all(self):
+        """Plots all available fin plots.
+
+        Returns
+        -------
+        None
+        """
+        self.draw()
+        self.airfoil()
+        self.roll()
+        self.lift()
+
+
 class _TrapezoidalFinsPlots(_FinsPlots):
     """Class that contains all trapezoidal fin plots."""
 
@@ -309,6 +370,127 @@ def draw(self):
         plt.show()
 
 
+class _TrapezoidalFinPlots(_FinPlots):
+    """Class that contains all trapezoidal 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]
+        # Fin
+        leading_edge = plt.Line2D(
+            (0, self.aero_surface.sweep_length),
+            (0, self.aero_surface.span),
+            color="#A60628",
+        )
+        tip = plt.Line2D(
+            (
+                self.aero_surface.sweep_length,
+                self.aero_surface.sweep_length + self.aero_surface.tip_chord,
+            ),
+            (self.aero_surface.span, self.aero_surface.span),
+            color="#A60628",
+        )
+        back_edge = plt.Line2D(
+            (
+                self.aero_surface.sweep_length + self.aero_surface.tip_chord,
+                self.aero_surface.root_chord,
+            ),
+            (self.aero_surface.span, 0),
+            color="#A60628",
+        )
+        root = plt.Line2D((self.aero_surface.root_chord, 0), (0, 0), color="#A60628")
+
+        # Center and Quarter line
+        center_line = plt.Line2D(
+            (
+                self.aero_surface.root_chord / 2,
+                self.aero_surface.sweep_length + self.aero_surface.tip_chord / 2,
+            ),
+            (0, self.aero_surface.span),
+            color="#7A68A6",
+            alpha=0.35,
+            linestyle="--",
+            label="Center Line",
+        )
+        quarter_line = plt.Line2D(
+            (
+                self.aero_surface.root_chord / 4,
+                self.aero_surface.sweep_length + self.aero_surface.tip_chord / 4,
+            ),
+            (0, self.aero_surface.span),
+            color="#7A68A6",
+            alpha=1,
+            linestyle="--",
+            label="Quarter Line",
+        )
+
+        # Center of pressure
+        cp_point = [self.aero_surface.cpz, self.aero_surface.Yma]
+
+        # Mean Aerodynamic Chord
+        yma_start = (
+            self.aero_surface.sweep_length
+            * (self.aero_surface.root_chord + 2 * self.aero_surface.tip_chord)
+            / (3 * (self.aero_surface.root_chord + self.aero_surface.tip_chord))
+        )
+        yma_end = (
+            2 * self.aero_surface.root_chord**2
+            + self.aero_surface.root_chord * self.aero_surface.sweep_length
+            + 2 * self.aero_surface.root_chord * self.aero_surface.tip_chord
+            + 2 * self.aero_surface.sweep_length * self.aero_surface.tip_chord
+            + 2 * self.aero_surface.tip_chord**2
+        ) / (3 * (self.aero_surface.root_chord + self.aero_surface.tip_chord))
+        yma_line = plt.Line2D(
+            (yma_start, yma_end),
+            (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.add_line(leading_edge)
+        ax.add_line(tip)
+        ax.add_line(back_edge)
+        ax.add_line(root)
+
+        ax.add_line(center_line)
+        ax.add_line(quarter_line)
+        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
+        xlim = (
+            self.aero_surface.root_chord
+            if self.aero_surface.sweep_length + self.aero_surface.tip_chord
+            < self.aero_surface.root_chord
+            else self.aero_surface.sweep_length + self.aero_surface.tip_chord
+        )
+        ax.set_xlim(0, xlim * 1.1)
+        ax.set_ylim(0, self.aero_surface.span * 1.1)
+        ax.set_xlabel("Root chord (m)")
+        ax.set_ylabel("Span (m)")
+        ax.set_title("Trapezoidal Fin Cross Section")
+        ax.legend(bbox_to_anchor=(1.05, 1.0), loc="upper left")
+
+        plt.tight_layout()
+        plt.show()
+
+
 class _EllipticalFinsPlots(_FinsPlots):
     """Class that contains all elliptical fin plots."""
 
@@ -380,6 +562,77 @@ def draw(self):
         plt.show()
 
 
+class _EllipticalFinPlots(_FinPlots):
+    """Class that contains all elliptical fin plots."""
+
+    # pylint: disable=too-many-statements
+    def draw(self):
+        """Draw the fin shape along with some important information.
+        These being: the center line and the center of pressure position.
+
+        Returns
+        -------
+        None
+        """
+        # Ellipse
+        ellipse = Ellipse(
+            (self.aero_surface.root_chord / 2, 0),
+            self.aero_surface.root_chord,
+            self.aero_surface.span * 2,
+            fill=False,
+            edgecolor="#A60628",
+            linewidth=2,
+        )
+
+        # Mean Aerodynamic Chord # From Barrowman's theory
+        yma_length = 8 * self.aero_surface.root_chord / (3 * np.pi)
+        yma_start = (self.aero_surface.root_chord - yma_length) / 2
+        yma_end = (
+            self.aero_surface.root_chord
+            - (self.aero_surface.root_chord - yma_length) / 2
+        )
+        yma_line = plt.Line2D(
+            (yma_start, yma_end),
+            (self.aero_surface.Yma, self.aero_surface.Yma),
+            label="Mean Aerodynamic Chord",
+            color="#467821",
+        )
+
+        # Center Line
+        center_line = plt.Line2D(
+            (self.aero_surface.root_chord / 2, self.aero_surface.root_chord / 2),
+            (0, self.aero_surface.span),
+            color="#7A68A6",
+            alpha=0.35,
+            linestyle="--",
+            label="Center Line",
+        )
+
+        # Center of pressure
+        cp_point = [self.aero_surface.cpz, self.aero_surface.Yma]
+
+        # Plotting
+        fig = plt.figure(figsize=(7, 4))
+        with plt.style.context("bmh"):
+            ax = fig.add_subplot(111)
+        ax.add_patch(ellipse)
+        ax.add_line(yma_line)
+        ax.add_line(center_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_xlim(0, self.aero_surface.root_chord)
+        ax.set_ylim(0, self.aero_surface.span * 1.1)
+        ax.set_xlabel("Root chord (m)")
+        ax.set_ylabel("Span (m)")
+        ax.set_title("Elliptical 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/plots/rocket_plots.py

@@ -4,7 +4,7 @@
 import numpy as np
 
 from rocketpy.motors import EmptyMotor, HybridMotor, LiquidMotor, SolidMotor
-from rocketpy.rocket.aero_surface import Fins, NoseCone, Tail
+from rocketpy.rocket.aero_surface import Fin, Fins, NoseCone, Tail
 
 
 class _RocketPlots:
@@ -242,6 +242,8 @@ def _draw_aerodynamic_surfaces(self, ax, vis_args):
                 self._draw_tail(ax, surface, position.z, drawn_surfaces, vis_args)
             elif isinstance(surface, Fins):
                 self._draw_fins(ax, surface, position.z, drawn_surfaces, vis_args)
+            elif isinstance(surface, Fin):
+                self._draw_fin(ax, surface, position.z, drawn_surfaces, vis_args)
         return drawn_surfaces
 
     def _draw_nose_cone(self, ax, surface, position, drawn_surfaces, vis_args):
@@ -334,6 +336,35 @@ def _draw_fins(self, ax, surface, position, drawn_surfaces, vis_args):
 
         drawn_surfaces.append((surface, position, surface.rocket_radius, x_rotated[-1]))
 
+    def _draw_fin(self, ax, surface, position, drawn_surfaces, vis_args):
+        """Draws the fins and saves the position of the points of interest
+        for the tubes."""
+
+        x_fin = -self.rocket._csys * surface.shape_vec[0] + position
+        y_fin = surface.shape_vec[1] + surface.rocket_radius
+        angle = surface.angular_position
+
+        # Create a rotation matrix for the angle around the x-axis
+        rotation_matrix = np.array([[1, 0], [0, np.cos(angle)]])
+
+        # Apply the rotation to the original fin points
+        rotated_points_2d = np.dot(rotation_matrix, np.vstack((x_fin, y_fin)))
+
+        # Extract x and y coordinates of the rotated points
+        x_rotated, y_rotated = rotated_points_2d
+
+        # Project points above the XY plane back into the XY plane (set z-coordinate to 0)
+        x_rotated = np.where(rotated_points_2d[1] > 0, rotated_points_2d[0], x_rotated)
+        y_rotated = np.where(rotated_points_2d[1] > 0, rotated_points_2d[1], y_rotated)
+        ax.plot(
+            x_rotated,
+            y_rotated,
+            color=vis_args["fins"],
+            linewidth=vis_args["line_width"],
+        )
+
+        drawn_surfaces.append((surface, position, surface.rocket_radius, x_rotated[-1]))
+
     def _draw_tubes(self, ax, drawn_surfaces, vis_args):
         """Draws the tubes between the aerodynamic surfaces."""
         for i, d_surface in enumerate(drawn_surfaces):