Social Forces

class SocialForceBehavior

Bases: Behavior

Basic social force algorithm from

Helbing, Dirk, and Peter Molnar. “Social force model for pedestrian dynamics.” Physical review E 51.5 (1995): 4282.

Registered properties:

• tau [float]

• phi [float]

• c [float]

• u_a [float]

• u_r [float]

• v_a [float]

• v_r [float]

• step_duration [float]

State: GeometricState

__init__(kinematics: navground.core.Kinematics = None, radius: float = 0) → None

Constructs a new instance.

Parameters:

• kinematics – The kinematics of the agent.

• radius – The radius of the agent.

desired_velocity_towards_point(point: Vector2, speed: float, time_step: float) → Vector2

Computes a control velocity towards a desired position

Users may override it to specialize a Behavior.

The base implementation returns a null vector.

Parameters:

• point – The desired point in world-fixed frame

• speed – The desired speed

• time_step – The time step

Returns:

A velocity in world-fixed frame

desired_velocity_towards_velocity(velocity: Vector2, time_step: float) → Vector2

Computes a control velocity towards a desired velocity

Users may override it to specialize a Behavior.

The base implementation returns a null vector.

Parameters:

• velocity – The desired velocity in world-fixed frame

• time_step – The time step

Returns:

A velocity in world-fixed frame

get_environment_state() → navground.core.EnvironmentState

Gets the environment state.

Returns:

The environment state.

in_sight(force: Vector2, e: Vector2) → bool

neighbor_potential(neighbor: Neighbor) → Callable[[Vector2], float]

neighbor_repulsion_force(neighbor: Neighbor) → Vector2

obstacle_potential(obstacle: Disc) → Callable[[Vector2], float]

obstacle_repulsion_force(obstacle: Disc) → Vector2

potential() → Callable[[Vector2], float]

segment_potential(line: LineSegment) → Callable[[Vector2], float]

segment_repulsion_force(line: LineSegment) → Vector2

weight(force: Vector2, e: Vector2) → float

weighted(force: Vector2, e: Vector2, sign: int) → Vector2

property c: float

property phi: float

property step_duration: float

property tau: float

property u_a: float

property u_r: float

property v_a: float

property v_r: float