[DO NOT MERGE] Example of adding articulated cart into Arena obj library

isaaclab_arena/affordances/movable.py

@@ -0,0 +1,75 @@
+# Copyright (c) 2025-2026, The Isaac Lab Arena Project Developers (https://github.com/isaac-sim/IsaacLab-Arena/blob/main/CONTRIBUTORS.md).
+# All rights reserved.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+import torch
+
+import warp as wp
+from isaaclab.envs.manager_based_env import ManagerBasedEnv
+from isaaclab.managers import SceneEntityCfg
+
+from isaaclab_arena.affordances.affordance_base import AffordanceBase
+
+
+class Movable(AffordanceBase):
+    """Interface for objects that can be pushed or moved across the floor.
+
+    Movable objects are characterized by the ability to be displaced from their
+    initial position (e.g. carts on wheels, trolleys, wheeled furniture).
+    Displacement is measured in the XY-plane (horizontal movement only).
+    """
+
+    def __init__(self, displacement_threshold: float = 0.1, **kwargs):
+        """Initialize a movable object.
+
+        Args:
+            displacement_threshold: Default threshold (meters) for determining
+                whether the object has been moved. Measured as Euclidean
+                distance in the XY-plane.
+            **kwargs: Additional arguments passed to AffordanceBase.
+        """
+        super().__init__(**kwargs)
+        self.displacement_threshold = displacement_threshold
+
+    def get_displacement(self, env: ManagerBasedEnv, asset_cfg: SceneEntityCfg | None = None) -> torch.Tensor:
+        """Get horizontal (XY) displacement from the initial position.
+
+        Args:
+            env: The environment instance.
+            asset_cfg: Asset configuration. If None, uses the object's name.
+
+        Returns:
+            Euclidean distance in the XY-plane from the initial position.
+            Shape: [num_envs].
+        """
+        if asset_cfg is None:
+            asset_cfg = SceneEntityCfg(self.name)
+        object_entity = env.scene[asset_cfg.name]
+        current_pos = wp.to_torch(object_entity.data.root_pos_w)[:, :2]
+        initial_pos = wp.to_torch(object_entity.data.default_root_state)[:, :2]
+        env_origins_xy = env.scene.env_origins[:, :2]
+        return torch.norm(current_pos - (initial_pos + env_origins_xy), dim=-1)
+
+    def is_moved(
+        self,
+        env: ManagerBasedEnv,
+        asset_cfg: SceneEntityCfg | None = None,
+        displacement_threshold: float | None = None,
+    ) -> torch.Tensor:
+        """Check whether the object has been displaced beyond a threshold.
+
+        Args:
+            env: The environment instance.
+            asset_cfg: Asset configuration. If None, uses the object's name.
+            displacement_threshold: Threshold in meters. If None, uses the
+                object's default displacement_threshold.
+
+        Returns:
+            Boolean tensor indicating whether the object has been moved.
+            Shape: [num_envs].
+        """
+        if displacement_threshold is None:
+            displacement_threshold = self.displacement_threshold
+        displacement = self.get_displacement(env, asset_cfg)
+        return displacement > displacement_threshold

isaaclab_arena/assets/object_library.py

@@ -14,6 +14,7 @@
 from isaaclab.sim.spawners.from_files.from_files_cfg import GroundPlaneCfg
 from isaaclab.utils.assets import ISAAC_NUCLEUS_DIR, ISAACLAB_NUCLEUS_DIR
 
+from isaaclab_arena.affordances.movable import Movable
 from isaaclab_arena.affordances.openable import Openable
 from isaaclab_arena.affordances.placeable import Placeable
 from isaaclab_arena.affordances.pressable import Pressable
@@ -1968,3 +1969,45 @@ def _generate_rigid_cfg(self) -> RigidObjectCfg:
             **self.asset_cfg_addon,
         )
         return self._add_initial_pose_to_cfg(cfg)
+
+
+@register_asset
+class MobileShelvingCart(LibraryObject, Movable):
+    """A mobile shelving cart on caster wheels.
+
+    The USD has joints connecting rigid body links (body, swivels, wheels)
+    but no ArticulationRootAPI baked in, so we apply it at spawn time via
+    a custom spawner that calls ``define_articulation_root_properties``.
+    """
+
+    name = "mobile_shelving_cart"
+    tags = ["object", "movable"]
+    usd_path = "/datasets/assets/Collected_sm_mobileshelvingcart_a01/sm_mobileshelvingcart_a01.usd"
+    object_type = ObjectType.ARTICULATION
+    default_prim_path = "{ENV_REGEX_NS}/mobile_shelving_cart"
+    scale = (0.7, 0.7, 0.7)
+    displacement_threshold = 0.15
+    spawn_cfg_addon = {
+        "func": "isaaclab_arena.utils.usd.spawners:spawn_from_usd_and_add_articulation_root",
+        "articulation_props": sim_utils.ArticulationRootPropertiesCfg(
+            enabled_self_collisions=False,
+        ),
+    }
+    asset_cfg_addon = {
+        "init_state": EMPTY_ARTICULATION_INIT_STATE_CFG,
+    }
+
+    def __init__(
+        self,
+        instance_name: str | None = None,
+        prim_path: str | None = None,
+        initial_pose: Pose | None = None,
+        scale: tuple[float, float, float] | None = None,
+    ):
+        super().__init__(
+            instance_name=instance_name,
+            prim_path=prim_path,
+            initial_pose=initial_pose,
+            scale=scale,
+            displacement_threshold=self.displacement_threshold,
+        )

isaaclab_arena/tasks/move_object_task.py

@@ -0,0 +1,85 @@
+# Copyright (c) 2025-2026, The Isaac Lab Arena Project Developers (https://github.com/isaac-sim/IsaacLab-Arena/blob/main/CONTRIBUTORS.md).
+# All rights reserved.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+import numpy as np
+from dataclasses import MISSING
+
+import isaaclab.envs.mdp as mdp_isaac_lab
+from isaaclab.envs.common import ViewerCfg
+from isaaclab.managers import SceneEntityCfg, TerminationTermCfg
+from isaaclab.utils import configclass
+
+from isaaclab_arena.assets.asset import Asset
+from isaaclab_arena.embodiments.common.arm_mode import ArmMode
+from isaaclab_arena.metrics.metric_base import MetricBase
+from isaaclab_arena.metrics.success_rate import SuccessRateMetric
+from isaaclab_arena.tasks.task_base import TaskBase
+from isaaclab_arena.tasks.terminations import object_displaced
+from isaaclab_arena.utils.cameras import get_viewer_cfg_look_at_object
+
+
+class MoveObjectTask(TaskBase):
+    """Task where the robot must push/move a movable articulated object (e.g. a cart)."""
+
+    def __init__(
+        self,
+        movable_object: Asset,
+        background_scene: Asset,
+        displacement_threshold: float = 0.5,
+        episode_length_s: float = 10.0,
+        task_description: str | None = None,
+    ):
+        super().__init__(episode_length_s=episode_length_s)
+        self.movable_object = movable_object
+        self.background_scene = background_scene
+        self.displacement_threshold = displacement_threshold
+
+        self.scene_config = None
+        self.events_cfg = None
+        self.termination_cfg = self._make_termination_cfg()
+        self.task_description = (
+            f"Push the {movable_object.name} at least {displacement_threshold:.1f}m from its start"
+            if task_description is None
+            else task_description
+        )
+
+    def get_scene_cfg(self):
+        return self.scene_config
+
+    def get_termination_cfg(self):
+        return self.termination_cfg
+
+    def get_events_cfg(self):
+        return self.events_cfg
+
+    def get_mimic_env_cfg(self, arm_mode: ArmMode):
+        raise NotImplementedError("Mimic is not yet supported for MoveObjectTask.")
+
+    def get_metrics(self) -> list[MetricBase]:
+        return [SuccessRateMetric()]
+
+    def get_viewer_cfg(self) -> ViewerCfg:
+        return get_viewer_cfg_look_at_object(
+            lookat_object=self.movable_object,
+            offset=np.array([-2.0, -2.0, 2.0]),
+        )
+
+    def _make_termination_cfg(self):
+        success = TerminationTermCfg(
+            func=object_displaced,
+            params={
+                "object_cfg": SceneEntityCfg(self.movable_object.name),
+                "displacement_threshold": self.displacement_threshold,
+            },
+        )
+        return MoveObjectTerminationsCfg(success=success)
+
+
+@configclass
+class MoveObjectTerminationsCfg:
+    """Termination terms for the move-object task."""
+
+    time_out: TerminationTermCfg = TerminationTermCfg(func=mdp_isaac_lab.time_out)
+    success: TerminationTermCfg = MISSING

isaaclab_arena/tasks/terminations.py

@@ -240,6 +240,31 @@ def goal_pose_task_termination(
     return success
 
 
+def object_displaced(
+    env: ManagerBasedRLEnv,
+    object_cfg: SceneEntityCfg = SceneEntityCfg("movable_object"),
+    displacement_threshold: float = 0.5,
+) -> torch.Tensor:
+    """Terminate (success) when the object has been displaced beyond a threshold.
+
+    Displacement is measured as XY-plane Euclidean distance from the initial position.
+
+    Args:
+        env: The RL environment instance.
+        object_cfg: The configuration of the movable object.
+        displacement_threshold: Minimum XY displacement in meters to count as success.
+
+    Returns:
+        A boolean tensor of shape (num_envs,) indicating success.
+    """
+    object_entity = env.scene[object_cfg.name]
+    current_pos = wp.to_torch(object_entity.data.root_pos_w)[:, :2]
+    initial_pos = wp.to_torch(object_entity.data.default_root_state)[:, :2]
+    env_origins_xy = env.scene.env_origins[:, :2]
+    displacement = torch.norm(current_pos - (initial_pos + env_origins_xy), dim=-1)
+    return displacement > displacement_threshold
+
+
 def root_height_below_minimum_multi_objects(
     env: ManagerBasedRLEnv, minimum_height: float, asset_cfg_list: list[SceneEntityCfg] = [SceneEntityCfg("robot")]
 ) -> torch.Tensor:

isaaclab_arena/utils/usd/spawners.py

@@ -0,0 +1,48 @@
+# Copyright (c) 2025-2026, The Isaac Lab Arena Project Developers (https://github.com/isaac-sim/IsaacLab-Arena/blob/main/CONTRIBUTORS.md).
+# All rights reserved.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+from __future__ import annotations
+
+from pxr import Usd
+
+from isaaclab.sim import schemas
+from isaaclab.sim.spawners.from_files.from_files import _spawn_from_usd_file
+from isaaclab.sim.spawners.from_files.from_files_cfg import UsdFileCfg
+from isaaclab.sim.utils import clone
+
+
+@clone
+def spawn_from_usd_and_add_articulation_root(
+    prim_path: str,
+    cfg: UsdFileCfg,
+    translation: tuple[float, float, float] | None = None,
+    orientation: tuple[float, float, float, float] | None = None,
+    **kwargs,
+) -> Usd.Prim:
+    """Spawn a USD file and apply ArticulationRootAPI to the root prim.
+
+    Use this for USD assets that have joints connecting rigid body links but
+    were authored without an ArticulationRootAPI. The API is applied to the
+    root prim after loading, so Isaac Lab can initialise the asset as an
+    articulation.
+
+    The function delegates to the standard USD spawning pipeline
+    (``_spawn_from_usd_file``) and then calls
+    ``schemas.define_articulation_root_properties`` which creates the
+    ArticulationRootAPI if it is not already present.
+
+    Args:
+        prim_path: The prim path or pattern to spawn the asset at.
+        cfg: The UsdFileCfg configuration instance.
+        translation: Translation w.r.t. parent prim. Defaults to None.
+        orientation: Orientation (x, y, z, w) w.r.t. parent prim. Defaults to None.
+
+    Returns:
+        The prim of the spawned asset.
+    """
+    prim = _spawn_from_usd_file(prim_path, cfg.usd_path, cfg, translation, orientation)
+    if cfg.articulation_props is not None:
+        schemas.define_articulation_root_properties(prim_path, cfg.articulation_props)
+    return prim

isaaclab_arena_environments/cli.py

@@ -21,6 +21,7 @@
     GR1TableMultiObjectNoCollisionEnvironment,
 )
 from isaaclab_arena_environments.gr1_turn_stand_mixer_knob_environment import Gr1TurnStandMixerKnobEnvironment
+from isaaclab_arena_environments.kitchen_move_object_environment import KitchenMoveObjectEnvironment
 from isaaclab_arena_environments.kitchen_pick_and_place_environment import KitchenPickAndPlaceEnvironment
 from isaaclab_arena_environments.lift_object_environment import LiftObjectEnvironment
 from isaaclab_arena_environments.pick_and_place_maple_table_environment import PickAndPlaceMapleTableEnvironment
@@ -39,6 +40,7 @@
     FrankaPutAndCloseDoorEnvironment.name: FrankaPutAndCloseDoorEnvironment,
     Gr1OpenMicrowaveEnvironment.name: Gr1OpenMicrowaveEnvironment,
     GR1PutAndCloseDoorEnvironment.name: GR1PutAndCloseDoorEnvironment,
+    KitchenMoveObjectEnvironment.name: KitchenMoveObjectEnvironment,
     KitchenPickAndPlaceEnvironment.name: KitchenPickAndPlaceEnvironment,
     GalileoPickAndPlaceEnvironment.name: GalileoPickAndPlaceEnvironment,
     PickAndPlaceMapleTableEnvironment.name: PickAndPlaceMapleTableEnvironment,

isaaclab_arena_environments/kitchen_move_object_environment.py

@@ -0,0 +1,70 @@
+# Copyright (c) 2025-2026, The Isaac Lab Arena Project Developers (https://github.com/isaac-sim/IsaacLab-Arena/blob/main/CONTRIBUTORS.md).
+# All rights reserved.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+import argparse
+
+from isaaclab_arena_environments.example_environment_base import ExampleEnvironmentBase
+
+
+class KitchenMoveObjectEnvironment(ExampleEnvironmentBase):
+
+    name: str = "kitchen_move_object"
+
+    def get_env(self, args_cli: argparse.Namespace):  # -> IsaacLabArenaEnvironment:
+        from isaaclab_arena.environments.isaaclab_arena_environment import IsaacLabArenaEnvironment
+        from isaaclab_arena.scene.scene import Scene
+        from isaaclab_arena.tasks.move_object_task import MoveObjectTask
+        from isaaclab_arena.utils.pose import Pose
+
+        background = self.asset_registry.get_asset_by_name("kitchen")()
+
+        embodiment = self.asset_registry.get_asset_by_name(args_cli.embodiment)(enable_cameras=args_cli.enable_cameras)
+
+        movable_object = self.asset_registry.get_asset_by_name(args_cli.object)()
+        movable_object.set_initial_pose(Pose(position_xyz=(-2, -0.1, 0), rotation_xyzw=(0.0, 0.0, 0.0, 1.0)))
+
+        if args_cli.teleop_device is not None:
+            teleop_device = self.device_registry.get_device_by_name(args_cli.teleop_device)()
+        else:
+            teleop_device = None
+
+        scene = Scene(assets=[background, movable_object])
+        move_object_task = MoveObjectTask(
+            movable_object=movable_object,
+            background_scene=background,
+            displacement_threshold=args_cli.displacement_threshold,
+            episode_length_s=args_cli.episode_length,
+        )
+        isaaclab_arena_environment = IsaacLabArenaEnvironment(
+            name=self.name,
+            embodiment=embodiment,
+            scene=scene,
+            task=move_object_task,
+            teleop_device=teleop_device,
+        )
+        return isaaclab_arena_environment
+
+    @staticmethod
+    def add_cli_args(parser: argparse.ArgumentParser) -> None:
+        parser.add_argument(
+            "--object",
+            type=str,
+            default="mobile_shelving_cart",
+            help="Movable articulated object to push.",
+        )
+        parser.add_argument("--embodiment", type=str, default="gr1_joint")
+        parser.add_argument(
+            "--displacement_threshold",
+            type=float,
+            default=0.5,
+            help="XY displacement (meters) to count as success.",
+        )
+        parser.add_argument(
+            "--episode_length",
+            type=float,
+            default=10.0,
+            help="Episode length in seconds.",
+        )
+        parser.add_argument("--teleop_device", type=str, default=None)