Objects

InternDataEngine supports various types of objects for simulation tasks. All object classes are located in workflows/simbox/core/objects/.

Supported Object Types

Class	Description
RigidObject	Rigid body objects with physics properties (graspable objects)
GeometryObject	Static geometry objects without physics (tables, fixtures)
ArticulatedObject	Articulated objects with joints (microwaves, drawers)
PlaneObject	Simple planes with textures (floors, backgrounds)
XFormObject	Transform-only objects
ShapeObject	Basic geometric shapes
ConveyorObject	Conveyor belt objects

RigidObject

RigidObject is used for objects that have physical properties and can be manipulated by robots. It inherits from Isaac Sim's RigidPrim and supports collision detection, mass properties, and texture randomization.

__init__(self, asset_root, root_prim_path, cfg, *args, **kwargs)

Initialize a rigid object in the simulation scene.

Parameters:

• asset_root (str): Root path for asset files.
• root_prim_path (str): Root prim path in USD stage.
• cfg (dict): Configuration dictionary containing:
  • name (str): Object name.
  • path (str): USD file path relative to asset_root.
  • prim_path_child (str): Child prim path for rigid body.
  • translation (list, optional): Initial translation [x, y, z].
  • euler (list, optional): Initial euler rotation [rx, ry, rz] in degrees.
  • scale (list, optional): Scale factor [sx, sy, sz].
  • mass (float, optional): Object mass.
• **kwargs: Additional keyword arguments passed to RigidPrim.

Config Example

objects:
  -
    name: pick_object_left
    path: pick_and_place/pre-train-pick/assets/omniobject3d-banana/omniobject3d-banana_001/Aligned_obj.usd
    target_class: RigidObject
    dataset: oo3d
    category: "omniobject3d-banana"
    prim_path_child: Aligned
    translation: [0.0, 0.0, 0.0]
    euler: [0.0, 0.0, 0.0]
    scale: [0.001, 0.001, 0.001]
    apply_randomization: True
    orientation_mode: "suggested"

Configuration Parameters

• name (str): Unique identifier for this object instance.
• path (str): Path to the USD file containing the object mesh.
• target_class (str): Must be RigidObject for rigid bodies.
• dataset (str): Dataset source identifier.
• category (str): Object category name.
• prim_path_child (str): Name of the child prim that contains the mesh.
• translation (list): Initial position [x, y, z] in world coordinates.
• euler (list): Initial rotation in degrees [roll, pitch, yaw].
• scale (list): Scale factors for each axis.
• apply_randomization (bool): Whether to apply domain randomization.
• orientation_mode (str): Orientation mode for randomization.

GeometryObject

GeometryObject is used for static objects without physics simulation. It's ideal for environmental objects like tables, shelves, or fixtures that don't need to interact physically with other objects.

__init__(self, asset_root, root_prim_path, cfg, *args, **kwargs)

Initialize a geometry object in the simulation scene.

Parameters:

• asset_root (str): Root path for asset files.
• root_prim_path (str): Root prim path in USD stage.
• cfg (dict): Configuration dictionary containing:
  • name (str): Object name.
  • path (str): USD file path relative to asset_root.
  • prim_path_child (str, optional): Child prim path suffix.
• **kwargs: Additional keyword arguments passed to GeometryPrim.

Difference from RigidObject:

• No physics simulation (no mass, no collision response)
• Lighter weight for static environment objects
• Cannot be grasped or moved by robots

Config Example

objects:
  -
    name: table
    path: table0/instance.usd
    target_class: GeometryObject
    translation: [0.0, 0.0, 0.375]
    scale: [0.001, 0.001053, 0.001056]

Configuration Parameters

• name (str): Unique identifier for this object.
• path (str): Path to the USD file.
• target_class (str): Must be GeometryObject for static geometry.
• translation (list): Position in world coordinates.
• scale (list): Scale factors for each axis.

PlaneObject

PlaneObject creates simple planes with optional texture mapping. It's commonly used for floors, backgrounds, and other flat surfaces.

__init__(self, asset_root, root_prim_path, cfg, *args, **kwargs)

Initialize a plane object in the simulation scene.

Parameters:

• asset_root (str): Root path for asset files.
• root_prim_path (str): Root prim path in USD stage.
• cfg (dict): Configuration dictionary containing:
  • name (str): Object name.
  • size (list): Plane dimensions [width, height].
  • translation (list, optional): Position [x, y, z].
  • euler (list, optional): Rotation in degrees [roll, pitch, yaw].
  • texture (dict, optional): Texture configuration.
• **kwargs: Additional keyword arguments.

Config Example

objects:
  -
    name: floor
    target_class: PlaneObject
    size: [5.0, 5.0]
    translation: [0, 0, 0]
    texture:
      texture_lib: "floor_textures"
      apply_randomization: True
      texture_id: 1
      texture_scale: [1.0, 1.0]
  -
    name: background0
    target_class: PlaneObject
    size: [3.0, 5.0]
    translation: [-2, 0, 1]
    euler: [0.0, 90.0, 0.0]
    texture:
      texture_lib: "background_textures"
      apply_randomization: True
      texture_id: 1
      texture_scale: [1.0, 1.0]
  -
    name: background1
    target_class: PlaneObject
    size: [3.0, 5.0]
    translation: [2, 0, 1]
    euler: [0.0, 90.0, 0.0]
    texture:
      texture_lib: "background_textures"
      apply_randomization: True
      texture_id: 1
      texture_scale: [1.0, 1.0]
  -
    name: background2
    target_class: PlaneObject
    size: [5.0, 3.0]
    translation: [0, -2, 1]
    euler: [90.0, 0.0, 0.0]
    texture:
      texture_lib: "background_textures"
      apply_randomization: True
      texture_id: 1
      texture_scale: [1.0, 1.0]
  -
    name: background3
    target_class: PlaneObject
    size: [5.0, 3.0]
    translation: [0, 2, 1]
    euler: [90.0, 0.0, 0.0]
    texture:
      texture_lib: "background_textures"
      apply_randomization: True
      texture_id: 1
      texture_scale: [1.0, 1.0]

Configuration Parameters

• name (str): Unique identifier for the plane.
• target_class (str): Must be PlaneObject.
• size (list): Plane dimensions [width, height].
• translation (list): Position [x, y, z].
• euler (list): Rotation angles [roll, pitch, yaw] in degrees.
• texture.texture_lib (str): Name of texture library folder.
• texture.apply_randomization (bool): Whether to randomize texture selection.
• texture.texture_id (int): Specific texture ID (used when randomization is False).
• texture.texture_scale (list): Scale factors for texture UV mapping.

ArticulatedObject

ArticulatedObject handles objects with movable joints, such as microwaves, drawers, and cabinets. It inherits from Isaac Sim's Articulation class and provides methods for joint control and state retrieval.

__init__(self, asset_root, root_prim_path, cfg, *args, **kwargs)

Initialize an articulated object in the simulation scene. Loads articulation info from the specified info.json file.

Parameters:

• asset_root (str): Root path for asset files.
• root_prim_path (str): Root prim path in USD stage.
• cfg (dict): Configuration dictionary containing:
  • name (str): Object name.
  • path (str): USD file path relative to asset_root.
  • info_name (str): Name of the skill folder containing info.json.
  • category (str): Object category identifier.
  • euler (list, optional): Initial rotation [roll, pitch, yaw].
  • joint_position_range (list, optional): Random range for initial joint position [min, max].
  • apply_randomization (bool, optional): Whether to apply domain randomization.
• **kwargs: Additional keyword arguments passed to Articulation.

get_articulated_info(self, object_info)

Parse and store articulation information from the object's info.json file. This method extracts keypoints, joint paths, scale information, and axis orientations.

Parameters:

• object_info (dict): Dictionary loaded from Kps/{skill}/info.json containing:
  • object_keypoints (dict): Keypoint positions in link_0 frame.
  • object_scale (list): Object scale factors.
  • object_prim_path (str): Prim path for the object.
  • object_link_path (str): Prim path for the articulated link.
  • object_base_path (str): Prim path for the base link.
  • object_joint_path (str): Prim path for the joint.
  • joint_index (int): Index of the main joint.
  • object_link0_rot_axis (str): Rotation axis of the link.
  • object_base_front_axis (str): Front axis of the base.

get_joint_position(self, stage)

Count and configure joints in the articulated object. This method identifies prismatic and revolute joints, and optionally fixes the base of the articulated object.

Parameters:

• stage (UsdStage): The USD stage containing the articulation.

Sets the following attributes:

• object_joint_number (int): Total number of joints found.

Config Example

objects:
  -
    name: close_v_left
    target_class: ArticulatedObject
    info_name: "close_v"
    euler: [0.0, 0.0, 90.0]
    joint_position_range: [0.6, 0.8]
    apply_randomization: False
    path: "art/microwave_gr/microwave7119/instance.usd"
    category: "microwave_gr"

Configuration Parameters

• name (str): Unique identifier for the articulated object.
• target_class (str): Must be ArticulatedObject.
• info_name (str): Name of the skill folder containing info.json.
• euler (list): Initial rotation [roll, pitch, yaw] in degrees.
• joint_position_range (list): Random range for initial joint position [min, max].
• apply_randomization (bool): Whether to apply domain randomization.
• path (str): Path to the USD file (relative to asset_root).
• category (str): Object category identifier.