Added nose, tube and wings, slight engine changes

rocket_twin/systems/__init__.py

@@ -3,8 +3,9 @@
 from rocket_twin.systems.ground import Ground
 from rocket_twin.systems.physics import Dynamics
 from rocket_twin.systems.tank import Pipe, Tank
+from rocket_twin.systems.structure import Nose, Tube, Wings
 
 from rocket_twin.systems.rocket import Rocket  # isort: skip
 from rocket_twin.systems.station import Station  # isort: skip
 
-__all__ = ["Clock", "Engine", "Tank", "Rocket", "Pipe", "Dynamics", "Station", "Ground"]
+__all__ = ["Clock", "Engine", "Tank", "Rocket", "Pipe", "Dynamics", "Station", "Ground", "Nose", "Tube", "Wings"]

rocket_twin/systems/engine/engine.py

@@ -7,7 +7,9 @@ class Engine(System):
     Inputs
     ------
     force_command: float,
-        External control, which inputs the % of the maximum force the engine outputs
+        external control, which inputs the % of the maximum force the engine outputs
+    w_out [kg/s]: float,
+        rate of fuel consumption
 
     Outputs
     ------
@@ -21,15 +23,18 @@ class Engine(System):
 
     def setup(self):
 
-        self.add_inward("force_max", 100.0, desc="Maximum engine force", unit="N")
+        #self.add_inward("force_max", 100.0, desc="Maximum engine force", unit="N")
         self.add_inward(
             "force_command", 1.0, desc="Ratio of command force to maximum force", unit=""
         )
+        self.add_inward("isp", 100., desc="Specific impulsion in vacuum", unit='s')
+        self.add_inward("w_out", 0., desc="Fuel consumption rate", unit='kg/s')
+        self.add_inward("g_0", 9.80665, desc="Gravity at Earth's surface", unit='m/s**2')
 
         self.add_outward("weight", 1.0, desc="weight", unit="kg")
         self.add_outward("cg", 1.0, desc="Center of Gravity", unit="m")
         self.add_outward("force", 1.0, desc="Thrust force", unit="N")
 
     def compute(self):
 
-        self.force = self.force_max * self.force_command
+        self.force = self.isp * self.g_0 * self.w_out * self.force_command

rocket_twin/systems/rocket/rocket.py

@@ -1,6 +1,6 @@
 from cosapp.base import System
 
-from rocket_twin.systems import Dynamics, Engine, Tank
+from rocket_twin.systems import Dynamics, Engine, Tank, Nose, Tube, Wings
 
 
 class Rocket(System):
@@ -16,24 +16,31 @@ class Rocket(System):
     """
 
     def setup(self):
+        self.add_child(Nose('nose'))
+        self.add_child(Tube('tube'))
+        self.add_child(Wings('wings'))
         self.add_child(Engine("engine"), pulling=["force_command"])
         self.add_child(Tank("tank"), pulling=["w_in", "w_command"])
         self.add_child(
             Dynamics(
                 "dyn",
                 forces=["thrust"],
-                weights=["weight_eng", "weight_tank"],
-                centers=["engine", "tank"],
+                weights=["weight_eng", "weight_tank", "weight_nose", "weight_tube", "weight_wings"],
+                centers=["engine", "tank", "nose", "tube", "engine"],
             ),
             pulling=["a"],
         )
 
+        self.connect(self.tank.outwards, self.engine.inwards, ['w_out'])
         self.connect(
             self.engine.outwards,
             self.dyn.inwards,
             {"force": "thrust", "weight": "weight_eng", "cg": "engine"},
         )
         self.connect(self.tank.outwards, self.dyn.inwards, {"weight": "weight_tank", "cg": "tank"})
+        self.connect(self.nose.outwards, self.dyn.inwards, {'weight' : 'weight_nose', 'cg' : 'nose'})
+        self.connect(self.tube.outwards, self.dyn.inwards, {'weight' : 'weight_tube', 'cg' : 'tube'})
+        self.connect(self.wings.outwards, self.dyn.inwards, {'weight' : 'weight_wings', 'cg' : 'wings'})
 
         self.add_inward("flying", False, desc="Whether the rocket is flying or not", unit="")
 

rocket_twin/systems/structure/__init__.py

@@ -0,0 +1,5 @@
+from rocket_twin.systems.structure.nose import Nose
+from rocket_twin.systems.structure.tube import Tube
+from rocket_twin.systems.structure.wings import Wings
+
+__all__ = ['Nose', 'Tube', 'Wings']

rocket_twin/systems/structure/nose.py

@@ -0,0 +1,20 @@
+from cosapp.base import System
+
+class Nose(System):
+    """Model of a rocket nose.
+
+    Inputs
+    ------
+
+    Outputs
+    ------
+    weight [kg]: float,
+        nose weight
+    cg [m]: float,
+        nose center of gravity
+    """
+
+    def setup(self):
+
+        self.add_outward('weight', 0., desc="Weight", unit='kg')
+        self.add_outward('cg', 0., desc="Center of gravity", unit='m')

rocket_twin/systems/structure/tube.py

@@ -0,0 +1,20 @@
+from cosapp.base import System
+
+class Tube(System):
+    """Model of a rocket tube.
+
+    Inputs
+    ------
+
+    Outputs
+    ------
+    weight [kg]: float,
+        tube weight
+    cg [m]: float,
+        tube center of gravity
+    """
+
+    def setup(self):
+
+        self.add_outward('weight', 0., desc="Weight", unit='kg')
+        self.add_outward('cg', 0., desc="Center of gravity", unit='m')

rocket_twin/systems/structure/wings.py

@@ -0,0 +1,20 @@
+from cosapp.base import System
+
+class Wings(System):
+    """Model of the wings of a rocket.
+
+    Inputs
+    ------
+
+    Outputs
+    ------
+    weight [kg]: float,
+        wings weight
+    cg [m]: float,
+        wings center of gravity
+    """
+
+    def setup(self):
+
+        self.add_outward('weight', 0., desc="Weight", unit='kg')
+        self.add_outward('cg', 0., desc="Center of gravity", unit='m')