pcg_gazebo.generators.engines

pcg_gazebo.generators.engines¶

Pose generator engine definitions that compute the pose of the models according to pre-defined rules.

create_engine¶

create_engine(tag, **kwargs)

Engine factory that returns the engine according to its LABEL definition. It returns None if the engine name is invalid.

tag (type: str): Name of the engine class
kwargs: Inputs for the engine class constructor

Engine¶

Engine()

Base class for model factory engines. The engines are responsible of computing poses for models in the world and performing collision checks within the scenario before the final world is generated. This class includes methods common to all derived engine classes.

callback_fcn_get_model (type: callable): Handle to a function or a lambda function that returns a pcg_gazebo.simulation.SimulationModel associated with a tag name.
callback_fcn_get_constraint (type: callable, default: None): Handle to a function or a lambda function that returns a pcg_gazebo.constraints.Constraint associated with a tag name.
models (type: list, default: None): List of models names as str relative to the models that the engine will have as assets.
constraints (type: list, default: None): List of local constraint configurations that will be applied on to the engine's model assets.

label¶

str: Engine name identifier

models¶

List of str: List of model name tags regarding the engine's model assets

poses¶

dict: List of fixed poses associated with model names.

add_local_constraint¶

Engine.add_local_constraint(model_name, constraint_name)

Add an association of a constraint definitions with an specific model tag to be taken into account when running the placement engine.

model_name (type: str): Name of the model
constraint_name (type: str): Name of the constraint definition

get_local_constraints_for_model¶

Engine.get_local_constraints_for_model(model_name)

Return the name of the local constraint definitions for a model.

model_name (type: str): Name of the model

List of str: List of constraint definition names associated with the model. If the model has no constraints, am empty list is returned.

apply_local_constraints¶

Engine.apply_local_constraints(model)

Apply spatial constraints to model. This will modify the pose of the model if it violates the constraint.

model (type: pcg_gazebo.simulation.SimulationModel): Model instance

pcg_gazebo.simulation.SimulationModel: Model with modified pose.

add_model¶

Engine.add_model(model)

Add a model name to the list of model assets for this engine.

model (type: str): Name of the model

set_fixed_pose_models¶

Engine.set_fixed_pose_models(models)

Function description

param (type: data_type, default: data): Parameter description

Description of return values

run¶

Engine.run()

This function should be implemented by the derived classes.

FixedPoseEngine¶

FixedPoseEngine()

Engine that just places models on pre-configured fixed poses. This engine only accepts one model asset.

callback_fcn_get_model (type: callable): Handle to a function or a lambda function that returns a pcg_gazebo.simulation.SimulationModel associated with a tag name.
callback_fcn_get_constraint (type: callable, default: None): Handle to a function or a lambda function that returns a pcg_gazebo.constraints.Constraint associated with a tag name.
models (type: list, default: None): List of models names as str relative to the models that the engine will have as assets.
constraints (type: list, default: None): List of local constraint configurations that will be applied on to the engine's model assets.
poses (type: list): List of 6- (position and Euler angles) or 7 element (position and quaternion) poses.

add_pose¶

FixedPoseEngine.add_pose(pose)

Add pose to the list of fixed-poses.

pose (type: list): 6- (position and Euler angles) or 7 element (position and quaternion) poses.

run¶

FixedPoseEngine.run()

Generate instances of the model asset for all the poses provided. If any local constraints were also provided, they will be applied to the model after its placement.

List of pcg_gazebo.simulation.SimulationModel: Model instances.

PatternEngine¶

PatternEngine()

RandomPoseEngine¶

RandomPoseEngine()

Placement engine that generates a random pose for its model assets respecting input local constraints, if any is provided, such as workspace constraint. This engine performs also a collision check with all models already placed in the scene (except for models flagged as ground plane) to ensure no models are overlapping each other.

callback_fcn_get_model (type: callable): Handle to a function or a lambda function that returns a pcg_gazebo.simulation.SimulationModel associated with a tag name.
callback_fcn_get_constraint (type: callable, default: None): Handle to a function or a lambda function that returns a pcg_gazebo.constraints.Constraint associated with a tag name.
models (type: list, default: None): List of models names as str relative to the models that the engine will have as assets.
constraints (type: list, default: None): List of local constraint configurations that will be applied on to the engine's model assets.
max_num (type: dict, default: None): Maximum number of instances of the model assets, the key being the model asset's name, and the value the maximum number.
no_collision (type: bool, default: True): If True, the model instances are only added to the world if there are no collisions with the already existing models (except for models flagged as ground plane).
max_area (type: float, default: 1): Percentage of the allowed area to fill with the models.
model_picker (type: str, default: random): Strategy for picking a model from the list of assets for the next placement in the world. Options are random (selecting a random model from the list of assets) or area (selecting the models for the biggest to the smallest).
policies (type: dict, default: None): The rules for model generation associated with each degree of freedom.

policies:
    - models:
     - model_1
     - model_2
     - model_3
     config:
     - dofs:
       - x
       - y
       policy:
         name: workspace
         args: area_1     # For more information on workspaces, check the class definition for `pcg_gazebo.constraints.WorkspaceConstraint`
     - dofs:
       - z
       - roll
       - pitch
       policy:
         name: value
         args: 0
     - dofs:
       - yaw
       policy:
         name: uniform
         args:
            min: -3.141592653589793
            max: 3.141592653589793

reset_counter¶

RandomPoseEngine.reset_counter()

Reset all model counters.

increase_counter¶

RandomPoseEngine.increase_counter(name)

Increase the counter for a model.

name (type: str): Model name

get_num_models¶

RandomPoseEngine.get_num_models(name)

Return the current value for the model counter.

name (type: str): Model name

int: Number of models

get_max_num_models¶

RandomPoseEngine.get_max_num_models(name)

Return the defined maximum number of instances for a model.

name (type: str): Model name

int: Maximum number of instances

choose_model¶

RandomPoseEngine.choose_model()

Select the next model instance to be placed in the world. This method is affected by the constructor input model_picker. In case the model_picker option was set as random, a random model will be chosen from the assets available. If it is area, the models will be ordered by footprint size and the models are chosen by an descending footprint size.

pcg_gazebo.simulation.SimulationModel: Chosen model

is_model_in_workspace¶

RandomPoseEngine.is_model_in_workspace(footprint)

Verify if the model is in the allowed workspace

footprint (type: dict or shapely.geometries.Polygon): A shapely polygon or a dictionary with the values being the footprints for different submodels.

bool: True if the polygon is entirely contained inside the workspace

get_list_of_footprint_polygons¶

RandomPoseEngine.get_list_of_footprint_polygons(footprint)

Return the list of polygons contained in the footprint input.

footprint (type: dict or shapely.geometries.Polygon): A shapely polygon or a dictionary with the values being the footprints for different submodels.

List of shapely.geometry.Polygon: List of footprint polygons

has_collision¶

RandomPoseEngine.has_collision(model)

Run the collision checker of the input model against the current scene of the simulation.

model (type: pcg_gazebo.simulation.SimulationModel):

bool: True, if any collision is detected

run¶

RandomPoseEngine.run()

Run the placement engine and generate a list of models placed according to the input policies and respecting spatial constraints.

List of pcg_gazebo.simulation.SimulationModel