pycram.pose_generator_and_validator

Module Contents

Classes

PoseGenerator

Crates pose candidates from a given costmap. The generator

Functions

visibility_validator(→ bool)

This method validates if the robot can see the target position from a given

_in_contact(→ bool)

This method checks if a given robot is in contact with a given object.

reachability_validator(→ typing_extensions.Tuple[bool, ...)

This method validates if a target position is reachable for a pose candidate.

collision_check(robot, allowed_collision)

This method checks if a given robot collides with any object within the world
class pycram.pose_generator_and_validator.PoseGenerator(costmap: pycram.costmaps.Costmap, number_of_samples=100, orientation_generator=None)

Crates pose candidates from a given costmap. The generator selects the highest values, amount is given by number_of_sample, and returns the corresponding positions. Orientations are calculated such that the Robot faces the center of the costmap.

Parameters:

  • costmap – The costmap from which poses should be sampled.

  • number_of_samples – The number of samples from the costmap that should be returned at max

  • orientation_generator – function that generates an orientation given a position and the origin of the costmap

current_orientation_generator

If no orientation generator is given, this generator is used to generate the orientation of the robot.

override_orientation_generator

Override the orientation generator with a custom generator, which will be used regardless of the current_orientation_generator.

__iter__() → typing_extensions.Iterable

A generator that crates pose candidates from a given costmap. The generator selects the highest 100 values and returns the corresponding positions. Orientations are calculated such that the Robot faces the center of the costmap.

Yield:

A tuple of position and orientation

static height_generator() → float
static generate_orientation(position: typing_extensions.List[float], origin: pycram.datastructures.pose.Pose) → typing_extensions.List[float]

This method generates the orientation for a given position in a costmap. The orientation is calculated such that the robot faces the origin of the costmap. This generation is done by simply calculating the arctan between the position, in the costmap, and the origin of the costmap.

Parameters:

  • position – The position in the costmap. This position is already converted to the world coordinate frame.

  • origin – The origin of the costmap. This is also the point which the robot should face.

Returns:

A quaternion of the calculated orientation

pycram.pose_generator_and_validator.visibility_validator(pose: pycram.datastructures.pose.Pose, robot: pycram.world_concepts.world_object.Object, object_or_pose: typing_extensions.Union[pycram.world_concepts.world_object.Object, pycram.datastructures.pose.Pose], world: pycram.world.World) → bool

This method validates if the robot can see the target position from a given pose candidate. The target position can either be a position, in world coordinate system, or an object in the World. The validation is done by shooting a ray from the camera to the target position and checking that it does not collide with anything else.

Parameters:

  • pose – The pose candidate that should be validated

  • robot – The robot object for which this should be validated

  • object_or_pose – The target position or object for which the pose candidate should be validated.

  • world – The World instance in which this should be validated.

Returns:

True if the target is visible for the robot, None in any other case.

pycram.pose_generator_and_validator._in_contact(robot: pycram.world_concepts.world_object.Object, obj: pycram.world_concepts.world_object.Object, allowed_collision: typing_extensions.Dict[pycram.world_concepts.world_object.Object, typing_extensions.List[str]], allowed_robot_links: typing_extensions.List[str]) → bool

This method checks if a given robot is in contact with a given object.

Parameters:

  • robot – The robot object that should be checked for contact.

  • obj – The object that should be checked for contact with the robot.

  • allowed_collision – A dictionary that contains the allowed collisions for links of each object in the world.

  • allowed_robot_links – A list of links of the robot that are allowed to be in contact with the object.

Returns:

True if the robot is in contact with the object and False otherwise.

pycram.pose_generator_and_validator.reachability_validator(pose: pycram.datastructures.pose.Pose, robot: pycram.world_concepts.world_object.Object, target: typing_extensions.Union[pycram.world_concepts.world_object.Object, pycram.datastructures.pose.Pose], allowed_collision: typing_extensions.Dict[pycram.world_concepts.world_object.Object, typing_extensions.List] = None) → typing_extensions.Tuple[bool, typing_extensions.List]

This method validates if a target position is reachable for a pose candidate. This is done by asking the ik solver if there is a valid solution if the robot stands at the position of the pose candidate. if there is a solution the validator returns True and False in any other case.

Parameters:

  • pose – The pose candidate for which the reachability should be validated

  • robot – The robot object in the World for which the reachability should be validated.

  • target – The target position or object instance which should be the target for reachability.

  • allowed_collision – dict of objects with which the robot is allowed to collide each object correlates to a list of links of which this object consists

Returns:

True if the target is reachable for the robot and False in any other case.

pycram.pose_generator_and_validator.collision_check(robot: pycram.world_concepts.world_object.Object, allowed_collision: list)

This method checks if a given robot collides with any object within the world which it is not allowed to collide with. This is done checking iterating over every object within the world and checking if the robot collides with it. Careful the floor will be ignored. If there is a collision with an object that was not within the allowed collision list the function returns True else it will return False

Parameters:

  • robot – The robot object in the (Bullet)World where it should be checked if it collides with something

  • allowed_collision – dict of objects with which the robot is allowed to collide each object correlates to a list of links of which this object consists

Returns:

True if the target is reachable for the robot and False in any other case.