Fixes idle action in replay script for GR1 Pick-Place env (#360)

# Description

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to check the contribution guidelines.

Link:
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Adds an "idle_action" parameter to the GR1 pick-place env. The
replay_demo script is also updated to check if envs have an idle action
pre-defined in its config and uses it if present. If not present, the
replay script will continue to use a zero tensor for idle actions.

This fixes errors during demo replay if an env doesn't support a zero
action tensor.

## Type of change

<!-- As you go through the list, delete the ones that are not
applicable. -->

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


## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [ ] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [x] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

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scripts/tools/replay_demos.py

@@ -162,6 +162,12 @@ def main():
     elif args_cli.validate_states and num_envs > 1:
         print("Warning: State validation is only supported with a single environment. Skipping state validation.")
 
+    # Get idle action (idle actions are applied to envs without next action)
+    if hasattr(env_cfg, "idle_action"):
+        idle_action = env_cfg.idle_action.repeat(num_envs, 1)
+    else:
+        idle_action = torch.zeros(env.action_space.shape)
+
     # reset before starting
     env.reset()
     teleop_interface.reset()
@@ -175,8 +181,8 @@ def main():
             first_loop = True
             has_next_action = True
             while has_next_action:
-                # initialize actions with zeros so those without next action will not move
-                actions = torch.zeros(env.action_space.shape)
+                # initialize actions with idle action so those without next action will not move
+                actions = idle_action
                 has_next_action = False
                 for env_id in range(num_envs):
                     env_next_action = env_episode_data_map[env_id].get_next_action()

source/isaaclab_tasks/config/extension.toml

 [package]
 
 # Note: Semantic Versioning is used: https://semver.org/
-version = "0.10.30"
+version = "0.10.31"
 
 # Description
 title = "Isaac Lab Environments"

source/isaaclab_tasks/docs/CHANGELOG.rst

 Changelog
 ---------
 
+0.10.31 (2025-04-02)
+~~~~~~~~~~~~~~~~~~~~
+
+Changed
+^^^^^^^
+
+* Adds an idle action parameter to the ``Isaac-PickPlace-GR1T2-Abs-v0`` environment configuration.
+
+
 0.10.30 (2025-03-25)
 ~~~~~~~~~~~~~~~~~~~~
 

source/isaaclab_tasks/isaaclab_tasks/manager_based/manipulation/pick_place/pickplace_gr1t2_env_cfg.py

@@ -4,6 +4,7 @@
 # SPDX-License-Identifier: BSD-3-Clause
 
 import tempfile
+import torch
 
 from pink.tasks import FrameTask
 
@@ -342,6 +343,48 @@ class PickPlaceGR1T2EnvCfg(ManagerBasedRLEnvCfg):
     # Temporary directory for URDF files
     temp_urdf_dir = tempfile.gettempdir()
 
+    # Idle action to hold robot in default pose
+    # Action format: [left arm pos (3), left arm quat (4), right arm pos (3), right arm quat (4),
+    #                 left hand joint pos (11), right hand joint pos (11)]
+    idle_action = torch.tensor([
+        -0.22878,
+        0.2536,
+        1.0953,
+        0.5,
+        0.5,
+        -0.5,
+        0.5,
+        0.22878,
+        0.2536,
+        1.0953,
+        0.5,
+        0.5,
+        -0.5,
+        0.5,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+        0.0,
+    ])
+
     def __post_init__(self):
         """Post initialization."""
         # general settings