enh: remade position an input for the aeroSurfaces list

made position also save in the object

Author: MateusStano

rocketpy/AeroSurfaces.py

@@ -11,18 +11,25 @@
 
 
 class AeroSurfaces:
-    """Class used to hold multiple aerodynamic surfaces."""
+    """Class used to hold one or more aerodynamic surfaces."""
 
     def __init__(self):
         self._aeroSurfaces = []
 
-    def append(self, aeroSurface):
-        self._aeroSurfaces.append(aeroSurface)
+    def append(self, aeroSurface, position=None):
+        if position:
+            self._aeroSurfaces.append((aeroSurface, position))
+        else:
+            self._aeroSurfaces.append(aeroSurface)
 
     def remove(self, aeroSurface):
         for surface in self._aeroSurfaces:
-            if surface == aeroSurface:
-                self._aeroSurfaces.remove(aeroSurface)
+            if isinstance(surface, tuple):
+                if surface[0] == aeroSurface:
+                    self._aeroSurfaces.remove((surface[0], surface[1]))
+            else:
+                if surface == aeroSurface:
+                    self._aeroSurfaces.remove(surface)
 
     def pop(self, index=-1):
         return self._aeroSurfaces.pop(index)
@@ -89,7 +96,6 @@ def __init__(
         self,
         length,
         kind,
-        position,
         baseRadius=None,
         rocketRadius=None,
         name="Nose Cone",
@@ -121,13 +127,13 @@ def __init__(
         """
         self.cpy = 0
         self.cpx = 0
+        self.position = None  # in relation to rocket
 
         self._rocketRadius = rocketRadius
         self._baseRadius = baseRadius
         self._length = length
         self.kind = kind
         self.name = name
-        self.position = position
 
         self.evaluateGeometricalParameters()
         self.evaluateLiftCoefficient()
@@ -258,7 +264,8 @@ def geometricalInfo(self):
         """
         print("Nose Cone Geometric Information of Nose: {}".format(self.name))
         print("-------------------------------")
-        print(f"Position: {self.position:.3f} m")
+        if self.position:
+            print(f"Position: {self.position:.3f} m")
         print(f"Length: {self.length:.3f} m")
         print(f"Kind: {self.kind}")
         print(f"Base Radius: {self.baseRadius:.3f} m")
@@ -385,7 +392,6 @@ def __init__(
         n,
         rootChord,
         span,
-        position,
         rocketRadius,
         cantAngle=0,
         airfoil=None,
@@ -440,9 +446,9 @@ def __init__(
         self._rootChord = rootChord
         self._span = span
         self.name = name
-        self.position = position
         self.d = d
         self.Aref = Aref  # Reference area
+        self.position = None  # in relation to rocket
 
         return None
 
@@ -753,7 +759,8 @@ def geometricalInfo(self):
             print("Fin Type: Elliptical")
         print("Root Chord: {:.3f} m".format(self.rootChord))
         print("Span: {:.3f} m".format(self.span))
-        print("Position: {:.3f} m".format(self.position))
+        if self.position:
+            print("Position: {:.3f} m".format(self.position))
         print("Cant Angle: {:.3f} °".format(self.cantAngle))
         print("Longitudinal Section Area: {:.3f} m".format(self.Af))
         print("Aspect Ratio: {:.3f} m".format(self.AR))
@@ -942,7 +949,6 @@ def __init__(
         rootChord,
         tipChord,
         span,
-        position,
         rocketRadius,
         cantAngle=0,
         sweepLength=None,
@@ -1006,7 +1012,6 @@ def __init__(
             n,
             rootChord,
             span,
-            position,
             rocketRadius,
             cantAngle,
             airfoil,
@@ -1354,7 +1359,6 @@ def __init__(
         n,
         rootChord,
         span,
-        position,
         rocketRadius,
         cantAngle=0,
         airfoil=None,
@@ -1414,7 +1418,6 @@ def __init__(
             n,
             rootChord,
             span,
-            position,
             rocketRadius,
             cantAngle,
             airfoil,
@@ -1656,9 +1659,7 @@ class Tail:
 
     """
 
-    def __init__(
-        self, topRadius, bottomRadius, length, position, rocketRadius, name="Tail"
-    ):
+    def __init__(self, topRadius, bottomRadius, length, rocketRadius, name="Tail"):
         """Initializes the tail object by computing and storing the most
         important values.
 
@@ -1687,8 +1688,7 @@ def __init__(
         self._length = length
         self._rocketRadius = rocketRadius
         self.name = name
-        self.position = position
-        # Calculate ratio between top and bottom radius
+        self.position = None  # in relation to rocket
 
         # Calculate geometrical parameters
         self.evaluateGeometricalParameters()
@@ -1820,7 +1820,8 @@ def geometricalInfo(self):
         """
 
         print(f"\nTail name: {self.name}")
-        print(f"Tail Position: {self.position:.3f} m")
+        if self.position:
+            print(f"Tail Position: {self.position:.3f} m")
         print(f"Tail Top Radius: {self.topRadius:.3f} m")
         print(f"Tail Bottom Radius: {self.bottomRadius:.3f} m")
         print(f"Tail Length: {self.length:.3f} m")

rocketpy/Flight.py

@@ -1409,9 +1409,9 @@ def uDot(self, t, u, postProcessing=False):
         vyB = a12 * vx + a22 * vy + a32 * vz
         vzB = a13 * vx + a23 * vy + a33 * vz
         # Calculate lift and moment for each component of the rocket
-        for aeroSurface in self.rocket.aerodynamicSurfaces:
+        for aeroSurface, position in self.rocket.aerodynamicSurfaces:
             compCp = (
-                aeroSurface.position - self.rocket.centerOfDryMassPosition
+                position - self.rocket.centerOfDryMassPosition
             ) * self.rocket._csys - aeroSurface.cpz
             surfaceRadius = aeroSurface.rocketRadius
             referenceArea = np.pi * surfaceRadius**2

rocketpy/Rocket.py

@@ -390,14 +390,14 @@ def evaluateStaticMargin(self):
 
         # Calculate total lift coefficient derivative and center of pressure
         if len(self.aerodynamicSurfaces) > 0:
-            for aeroSurface in self.aerodynamicSurfaces:
+            for aeroSurface, position in self.aerodynamicSurfaces:
                 self.totalLiftCoeffDer += Function(
                     lambda alpha: aeroSurface.cl(alpha, 0)
                 ).differentiate(x=1e-2, dx=1e-3)
                 self.cpPosition += Function(
                     lambda alpha: aeroSurface.cl(alpha, 0)
                 ).differentiate(x=1e-2, dx=1e-3) * (
-                    aeroSurface.position - self._csys * aeroSurface.cpz
+                    position - self._csys * aeroSurface.cpz
                 )
             self.cpPosition /= self.totalLiftCoeffDer
 
@@ -483,10 +483,12 @@ def addTail(
         radius = self.radius if radius is None else radius
 
         # Create new tail as an object of the Tail class
-        tail = Tail(topRadius, bottomRadius, length, position, radius, name)
+        tail = Tail(topRadius, bottomRadius, length, radius, name)
+        # Saves position on object for practicality
+        tail.position = position
 
         # Add tail to aerodynamic surfaces and tail list
-        self.aerodynamicSurfaces.append(tail)
+        self.aerodynamicSurfaces.append(aeroSurface=tail, position=position)
         self.tail.append(tail)
 
         # Refresh static margin calculation
@@ -522,10 +524,12 @@ def addNose(self, length, kind, position, name="Nose Cone"):
             Nose cone object created.
         """
         # Create a nose as an object of NoseCone class
-        nose = NoseCone(length, kind, position, self.radius, self.radius, name)
+        nose = NoseCone(length, kind, self.radius, self.radius, name)
+        # Saves position on object for practicality
+        nose.position = position
 
         # Add nose to the list of aerodynamic surfaces
-        self.aerodynamicSurfaces.append(nose)
+        self.aerodynamicSurfaces.append(aeroSurface=nose, position=position)
         self.nosecone.append(nose)
 
         # Refresh static margin calculation
@@ -628,17 +632,18 @@ def addTrapezoidalFins(
             rootChord,
             tipChord,
             span,
-            position,
             radius,
             cantAngle,
             sweepLength,
             sweepAngle,
             airfoil,
             name,
         )
+        # Saves position on object for practicality
+        finSet.position = position
 
         # Add fin set to the list of aerodynamic surfaces
-        self.aerodynamicSurfaces.append(finSet)
+        self.aerodynamicSurfaces.append(aeroSurface=finSet, position=position)
         self.fins.append(finSet)
 
         # Refresh static margin calculation
@@ -709,12 +714,12 @@ def addEllipticalFins(
         radius = radius if radius is not None else self.radius
 
         # Create a fin set as an object of EllipticalFins class
-        finSet = EllipticalFins(
-            n, rootChord, span, position, radius, cantAngle, airfoil, name
-        )
+        finSet = EllipticalFins(n, rootChord, span, radius, cantAngle, airfoil, name)
+        # Saves position on object for practicality
+        finSet.position = position
 
         # Add fin set to the list of aerodynamic surfaces
-        self.aerodynamicSurfaces.append(finSet)
+        self.aerodynamicSurfaces.append(aeroSurface=finSet, position=position)
         self.fins.append(finSet)
 
         # Refresh static margin calculation

rocketpy/prints/rocket_prints.py

@@ -105,28 +105,28 @@ def rocket_aerodynamics_quantities(self):
         """
         print("\nAerodynamics Lift Coefficient Derivatives\n")
         for aerodynamicSurface in self.rocket.aerodynamicSurfaces:
-            name = aerodynamicSurface.name
+            name = aerodynamicSurface[0].name
             try:
                 print(
                     name
                     + " Lift Coefficient Derivative: {:.3f}".format(
-                        aerodynamicSurface.clalpha(0)
+                        aerodynamicSurface[0].clalpha(0)
                     )
                     + "/rad"
                 )
             except:
                 print(
                     name
                     + " Lift Coefficient Derivative: {:.3f}".format(
-                        aerodynamicSurface.clalpha
+                        aerodynamicSurface[0].clalpha
                     )
                     + "/rad"
                 )
 
         print("\nAerodynamics Center of Pressure\n")
         for aerodynamicSurface in self.rocket.aerodynamicSurfaces:
-            name = aerodynamicSurface.name
-            cpz = aerodynamicSurface.cp[2]
+            name = aerodynamicSurface[0].name
+            cpz = aerodynamicSurface[0].cp[2]
             print(name + " Center of Pressure to CM: {:.3f}".format(cpz) + " m")
         print(
             "Distance - Center of Pressure to CM: "

tests/test_rocket.py

@@ -512,7 +512,7 @@ def test_add_trapezoidal_fins_sweep_length(
     assert translate - rocket.cpPosition == pytest.approx(expected_cpz_cm, 0.01)
 
     # Check if AeroSurfaces.__getitem__() works
-    assert isinstance(rocket.aerodynamicSurfaces.__getitem__(0), NoseCone)
+    assert isinstance(rocket.aerodynamicSurfaces.__getitem__(0)[0], NoseCone)
 
 
 def test_add_fins_assert_cp_cm_plus_fins(rocket, dimensionless_rocket, m):