Base Component¶

The base component is the fountain where ADR drinks from. Its idea is to provide several properties and methods that are necessary for both AttachedComponent and FreeBody. Usually the final user of ADR won't use BaseComponent directly, using instead the other two.

BaseComponent implements the idea of child components (with the children dictionary), methods for dealing with its state and the state of its children, methods for calculating the forces and moments on any component based on the loads in the component itself and its children, among other things.

Instantiation¶

One can instantiate a BaseComponent by passing three parameters: name, type and mass. Notice that all parameters should be passed as keyword arguments (eg.: name="plane").

from adr.Components import BaseComponent

base_component = BaseComponent(
    name='component',
    type='generic_component',
    mass=3.4)

print(base_component)
>>> BaseComponent(name='component', type='generic_component', mass=3.4, children={}, external_forces={}, external_moments={})

The other attributes (children, external_forces and external_moments) should not be passed during instantiation, but with specific methods.

reset_state method¶

The reset_state method will call the reset_children_state method. It exists so the classes inheriting from BaseComponent can always call it's superclass reset_state method, ultimately calling the reset_children_state method, which will reset all nested components.

reset_children_state method¶

The reset_children_state method will call the reset_state method of all the components listed on the children dictionary.

append_child method¶

This method is responsible for adding a child to a component

child_component = BaseComponent("wing1", "wing", 1.1)
base_component.append_child(child_component)

print(base_component.children)
>>> {'wing1': BaseComponent(name='wing1', type='wing', mass=1.1, children={}, external_forces={}, external_moments={})}

print(base_component.wing1)
>>> BaseComponent(name='wing1', type='wing', mass=1.1, children={}, external_forces={}, external_moments={})

angle_of_attack property¶

This property calculates the angle of attack of the plane

freebody_component = FreeBody(
    name='component',
    type='generic_component',
    mass=3.4,
    position_cg=Vector2(-0.7, 0.2),
    pitch_rot_inertia=30.0,
    ambient=Ambient()
)

attached_component = AttachedComponent(
    name='attached_component',
    type='generic_attached_component',
    mass=1.4,
    relative_position=Vector2(-0.4, 0.1),
    relative_angle=math.radians(9)
)

attached_component.set_parent(freebody_component)
freebody_component.velocity = Vector2(r=12, theta=math.radians(5))

print(math.degrees(freebody_component.angle_of_attack))
>>> -5.0

print(math.degrees(attached_component.angle_of_attack))
>>> 4.0

empty_mass property¶

This property returns the total mass of the nested components, excluding payload components

print(base_component.empty_mass)
>>> 4.5

nested_components property¶

This property returns a dictionary with the hierarchical relationship of each component

print(base_component.nested_components)
>>> {'component': BaseComponent(name='component', type='generic_component', mass=3.4, children={'wing1': BaseComponent(name='wing1', type='wing', mass=1.1, children={}, external_forces={}, external_moments={})}, external_forces={}, external_moments={}), 'wing1': BaseComponent(name='wing1', type='wing', mass=1.1, children={}, external_forces={}, external_moments={})}

add_external_force_function¶

This method is responsible for appending an external force function to the component. The force function returns a force vector and an application point.

def force1():
    mag = 10
    ang = math.radians(45)
    force_point = Vector2(-10, 0)
    force1 = Vector2(r=mag, theta=ang)
    return force1, force_point

base_component.add_external_force_function('force1', force1)

print(base_component.external_forces)
>>> {'force1': <function force1 at 0x0000025EBCAA8D30>}

add_external_moment_function:¶

This method is responsible for appending an external moment function to the component. The appended function should return a float representing the magnitude of the moment.

def moment1():
    moment1 = 13
    return moment1

base_component.add_external_moment_function('moment1', moment1)

print(base_component.external_moments)
>>> {'moment1': <function moment1 at 0x7ff87d8891f0>}

moment_from_external_moments method:¶

Returns the resultant pitch moment from the moment functions appended to the component. It does not include child's moments or moments from forces.

def moment_from_drag():
    return 2

def moment_from_lift():
    return 5

freebody_component.add_external_moment_function('drag_moment', moment_from_drag)
freebody_component.add_external_moment_function('lift_moment', moment_from_lift)

print(freebody_component.external_moments)
>>> {'drag_moment': <function moment_from_drag at 0x7fe44b2861f0>, 
     'lift_moment': <function moment_from_lift at 0x7fe44af67550>}
print(freebody_component.moment_from_external_moments())
>>> 7.0

force_and_moment_from_external_forces method:¶

Similar to moment_from_external_moments, but it returns both the resultant force and the moment of the resultant force on a component (excluding children).

def drag_force():
    return Vector2(-5, 0), Vector2(3, 2)

def lift_force():
    return Vector2(0, 50), Vector2(3, 2)

freebody_component.external_forces.pop('weight')
freebody_component.add_external_force_function('drag_force', drag_force)
freebody_component.add_external_force_function('lift_force', lift_force)

print(freebody_component.external_forces)
>>> {'drag_force': <function drag_force at 0x7f6fb6e561f0>,
     'lift_force': <function lift_force at 0x7f6f9f7d3310>}
print(freebody_component.force_and_moment_from_external_forces())
>>> (<Vector2 (-4.99999, 50)>, 160.0)

force_and_moment_from_children method:¶

Returns the resultant force and moment from all the child components at its origin.

force_and_moment_at_component_origin method:¶

Returns the resultant force and moment from itself and all the child components, at its origin.