klampt.model.create package

Utilities for creating primitives, moving base robots, canonical robot models, and stable piles.

Submodules

moving_base_robot	Common code for creating and moving free-floating moving bases.
pile	Utility functions for making arrangments / piles of objects.
primitives	Utilities for creating geometric primitives (and world entities made out of them).

klampt.model.create.moving_base_robot module

Common code for creating and moving free-floating moving bases.

The way to do this is to add a “virtual linkage” of 3 translational DOFs and 3 revolute DOFs. Some tuning may need to be done to the motor drivers in order to make the controller stable.

klampt.model.create.moving_base_robot.make(robotfile, world, tempname='temp.rob', debug=False)

Converts the given fixed-base robot file into a moving base robot and loads it into the given world.

Parameters:

• robotfile (str) – the name of a fixed-base robot file to load

• world (WorldModel) – a world that will contain the new robot

• tempname (str, optional) – a name of a temporary file containing the moving-base robot

• debug (bool, optional) – if True, the robot file named by tempname is not removed from disk.

Returns:

the loaded robot, stored in world.

Return type:

(RobotModel)

klampt.model.create.moving_base_robot.get_xform(robot)

For a moving base robot model, returns the current base rotation matrix R and translation t.

klampt.model.create.moving_base_robot.set_xform(robot, R, t)

For a moving base robot model, set the current base rotation matrix R and translation t. (Note: if you are controlling a robot during simulation, use send_moving_base_xform_command)

klampt.model.create.moving_base_robot.send_xform_linear(controller, R, t, dt)

For a moving base robot model, send a command to move to the rotation matrix R and translation t using linear interpolation over the duration dt.

Note: with the reflex model, can’t currently set hand commands and linear base commands simultaneously

klampt.model.create.moving_base_robot.send_xform_PID(controller, R, t)

For a moving base robot model, send a command to move to the rotation matrix R and translation t by setting the PID setpoint

Note: with the reflex model, can’t currently set hand commands and linear base commands simultaneously

klampt.model.create.pile module

Utility functions for making arrangments / piles of objects.

Main functions are make_object_arrangement() and make_object_pile().

klampt.model.create.pile.xy_randomize(obj, bmin, bmax)

Randomizes the xy position and z orientation of an object inside of a bounding box bmin->bmax. Assumes the bounding box is large enough to hold the object in any orientation.

klampt.model.create.pile.xy_jiggle(world, objects, fixed_objects, bmin, bmax, iters, randomize=True, verbose=0)

Jiggles the objects’ x-y positions within the range bmin - bmax, and randomizes orientation about the z axis until the objects are collision free. A list of fixed objects (fixed_objects) may be given as well.

Objects for which collision-free resolutions are not found are returned.

klampt.model.create.pile.make_object_arrangement(world, container, objects, container_wall_thickness=0.01, max_iterations=100, remove_failures=False)

For a given container and a list of objects in the world, places the objects inside the container with randomized x-y locations and z orientations so that they are initially collision free and on the bottom of the container.

Return type:

WorldModel

Parameters:

• world (WorldModel) – the world containing the objects and obstacles

• container – the container RigidObjectModel / TerrainModel in world into which objects should be spawned. Assumed axis-aligned.

• objects (list of RigidObjectModel) – a list of RigidObjects in the world, at arbitrary locations. They are placed in order.

• container_wall_thickness (float, optional) – a margin subtracted from the container’s outer dimensions into which the objects are spawned.

• max_iterations (int, optional) – the maximum number of iterations used for sampling object initial poses

• remove_failures (bool) – if True, then instead of returning None on failure, the objects that fail placement are removed from the world.

Returns:

if successful, the positions of objects in world are modified and world is returned. On failure, None is returned.

Return type:

WorldModel

Note

Since world is modified in-place, if you wish to make multiple worlds with piles of the same objects, you should use world.copy() to store the configuration of the objects. You may also wish to randomize the object ordering using random.shuffle(objects) between instances.

klampt.model.create.pile.make_object_pile(world, container, objects, container_wall_thickness=0.01, randomize_orientation=True, visualize=False, verbose=0)

For a given container and a list of objects in the world, drops the objects inside the container and simulates until stable.

Return type:

Tuple[WorldModel, Simulator]

Parameters:

• world (WorldModel) – the world containing the objects and obstacles

• container – the container RigidObjectModel / TerrainModel in world into which objects should be spawned. Assumed axis-aligned.

• objects (list of RigidObjectModel) – a list of RigidObjectModels in the world, at arbitrary locations. They are placed in order.

• container_wall_thickness (float, optional) – a margin subtracted from the container’s outer dimensions into which the objects are spawned.

• randomize_orientation (bool or str, optional) – if True, the orientation of the objects are completely randomized. If ‘z’, only the z orientation is randomized. If False or None, the orientation is unchanged

• visualize (bool, optional) – if True, pops up a visualization window to show the progress of the pile

• verbose (int, optional) – if > 0, prints progress of the pile.

Returns:

A pair (world,sim), containing

• world (WorldModel): the original world

• sim (Simulator): the Simulator instance at the state used to obtain

  the stable placement of the objects.

Note

If you wish to make multiple worlds with piles of the same objects, you may wish to randomize the object ordering using random.shuffle(objects) between instances.

klampt.model.create.primitives module

Utilities for creating geometric primitives (and world entities made out of them).

klampt.model.create.primitives.box(width, depth, height, center=None, R=None, t=None, world=None, name=None, mass=inf, type='TriangleMesh')

Makes a box with dimensions width x depth x height. The box is centered at (0,0,0) by default.

Parameters:

• width,depth,height (float) – x,y,z dimensions of the box

• center (list of 3 floats, optional) – if None (typical), the geometry of the box is centered at 0. Otherwise, the geometry of the box is shifted relative to the box’s local coordinate system.

• R,t (se3 transform, optional) – if given, the box’s world coordinates will be rotated and shifted by this transform.

• world (WorldModel, optional) – If given, then the box will be a RigidObjectModel or TerrainModel will be created in this world

• name (str, optional) – If world is given, this is the name of the object. Default is ‘box’.

• mass (float, optional) – If world is given and this is inf, then a TerrainModel will be created. Otherwise, a RigidObjectModel will be created with automatically determined inertia.

• type (str, optional) – the geometry type. Defaults to ‘TriangleMesh’, but also ‘GeometricPrimitive’ and ‘VolumeGrid’ are accepted.

Returns:

A representation of the box. If a world is given, then either a RigidObjectModel or TerrainModel is added to the world and returned.

Return type:

Geometry3D, RigidObjectModel, or TerrainModel

klampt.model.create.primitives.sphere(radius, center=None, R=None, t=None, world=None, name=None, mass=inf, type='TriangleMesh')

Makes a sphere with the given radius

Parameters:

• radius (float) – radius of the sphere

• center (list of 3 floats, optional) – if None (typical), the geometry of the sphere is centered at 0. Otherwise, the geometry of the sphere is shifted relative to the sphere’s local coordinate system.

• R,t (se3 transform, optional) – if given, the sphere’s world coordinates will be rotated and shifted by this transform.

• world (WorldModel, optional) – If given, then the sphere will be a RigidObjectModel or TerrainModel will be created in this world

• name (str, optional) – If world is given, this is the name of the object. Default is ‘sphere’.

• mass (float, optional) – If world is given and this is inf, then a TerrainModel will be created. Otherwise, a RigidObjectModel will be created with automatically determined inertia.

• type (str, optional) – the geometry type. Defaults to ‘TriangleMesh’, but also ‘GeometricPrimitive’ and ‘VolumeGrid’ are accepted.

Returns:

A representation of the sphere. If a world is given, then either a RigidObjectModel or TerrainModel is added to the world and returned.

Return type:

Geometry3D, RigidObjectModel, or TerrainModel

klampt.model.create.primitives.bbox(bmin, bmax, R=None, t=None, world=None, name=None, mass=inf, type='TriangleMesh')

Makes a box from bounds [bmin,bmax].

Parameters:

• bmin (list of 3 floats) – the lower corner of the box

• center (list of 3 floats) – the upper corner of the box

• R,t (se3 transform, optional) – if given, the box’s world coordinates will be rotated and shifted by this transform.

• world (WorldModel, optional) – If given, then the box will be a RigidObjectModel or TerrainModel will be created in this world

• name (str, optional) – If world is given, this is the name of the object. Default is ‘box’.

• mass (float, optional) – If world is given and this is inf, then a TerrainModel will be created. Otherwise, a RigidObjectModel will be created with automatically determined inertia.

• type (str, optional) – the geometry type. Defaults to ‘TriangleMesh’, but also ‘GeometricPrimitive’ and ‘VolumeGrid’ are accepted.

Returns:

A representation of the box. If a world is given, then either a RigidObjectModel or TerrainModel is added to the world and returned.

Return type:

Geometry3D, RigidObjectModel, or TerrainModel