Common

Realizations shared by several engineering systems, by family.

The families are mechanics and electrical components, and the car and its optimal velocity of the traffic systems.

CarElement(label, visual=None, *, x=0.0, v=0.0)

Bases: Element

Car on a road whose position x advances at its speed v.

Source code in src/skcomplex/systems/engineering/common/_car.py

def __init__(
    self,
    label: str,
    visual: VisualSpec | None = None,
    *,
    x: Annotated[object, StateSpec(role='position')] = 0.0,
    v: Annotated[object, StateSpec(role='velocity')] = 0.0,
) -> None:
    super().__init__(label, visual=visual)
    self.x = x
    self.v = v

OptimalVelocityInteraction(label, *, target, a=1.0, V0=1.0, hc=2.0, road_length=40.0)

Bases: RelaxationInteraction

Relaxation of the speed v of every car of a ring road towards the optimal velocity of its headway.

The speed follows v' = a (V(h) - v) with the optimal velocity V(h) = V0 (tanh(h - hc) + tanh(hc)) of the headway h to the next car, a relaxation over the time 1 / a.

Parameters:

Name	Type	Description	Default
label	str	The label of the interaction.	required
target	Annotated[str, RoleSpec()]	The path of the group of cars, in the order they drive.	required
a	Annotated[object, ParameterSpec(domain=open(0, oo))]	The sensitivity, the inverse of the relaxation time.	1.0
V0	Annotated[object, ParameterSpec(domain=open(0, oo))]	The scale of the optimal velocity.	1.0
hc	Annotated[object, ParameterSpec(domain=open(0, oo))]	The safe headway, where the optimal velocity turns.	2.0
road_length	Annotated[object, ParameterSpec(domain=open(0, oo))]	The length of the ring road.	40.0

Source code in src/skcomplex/systems/engineering/common/_optimal_velocity.py

def __init__(
    self,
    label: str,
    *,
    target: Annotated[str, RoleSpec()],
    a: Annotated[object, ParameterSpec(domain=RealSet.open(0, oo))] = 1.0,
    V0: Annotated[object, ParameterSpec(domain=RealSet.open(0, oo))] = 1.0,
    hc: Annotated[object, ParameterSpec(domain=RealSet.open(0, oo))] = 2.0,
    road_length: Annotated[object, ParameterSpec(domain=RealSet.open(0, oo))] = 40.0,
) -> None:
    super().__init__(label, target=target, state='v')
    self.a = a
    self.V0 = V0
    self.hc = hc
    self.road_length = road_length