Fixes offset from object obs for Franka stacking env when using parallel envs (#1839)

# Description

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The "object" obs group in the Franka stacking environment contains the
absolute position of each of the cubes. At the moment they are being
returned as world positions which include the env offset if running
multiple envs in parallel, causing inconsistent position values.

Fixes:

Eliminates the environment offset from the cube positions in the
"object" obs group of the Franka stacking environment by subtracting out
the environment origin.

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## Type of change

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- Bug fix (non-breaking change which fixes an issue)

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## Checklist

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source/isaaclab_tasks/config/extension.toml

 [package]
 
 # Note: Semantic Versioning is used: https://semver.org/
-version = "0.10.22"
+version = "0.10.23"
 
 # Description
 title = "Isaac Lab Environments"

source/isaaclab_tasks/docs/CHANGELOG.rst

 Changelog
 ---------
 
+0.10.23 (2025-02-11)
+~~~~~~~~~~~~~~~~~~~~
+
+Fixed
+^^^^^
+
+* Fixed the inconsistent object pos observations in the ``Isaac-Stack-Cube-Franka`` environment when using parallel envs by
+  subtracting out the env origin from each object pos observation.
+
+
 0.10.22 (2025-01-14)
 ~~~~~~~~~~~~~~~~~~~~
 

source/isaaclab_tasks/isaaclab_tasks/manager_based/manipulation/stack/mdp/observations.py

@@ -147,11 +147,11 @@ def object_obs(
 
     return torch.cat(
         (
-            cube_1_pos_w,
+            cube_1_pos_w - env.scene.env_origins,
             cube_1_quat_w,
-            cube_2_pos_w,
+            cube_2_pos_w - env.scene.env_origins,
             cube_2_quat_w,
-            cube_3_pos_w,
+            cube_3_pos_w - env.scene.env_origins,
             cube_3_quat_w,
             gripper_to_cube_1,
             gripper_to_cube_2,
@@ -225,11 +225,11 @@ def instance_randomize_object_obs(
 
     return torch.cat(
         (
-            cube_1_pos_w,
+            cube_1_pos_w - env.scene.env_origins,
             cube_1_quat_w,
-            cube_2_pos_w,
+            cube_2_pos_w - env.scene.env_origins,
             cube_2_quat_w,
-            cube_3_pos_w,
+            cube_3_pos_w - env.scene.env_origins,
             cube_3_quat_w,
             gripper_to_cube_1,
             gripper_to_cube_2,