fix(g1_env): apply gravity compensation torques in queue_action

gr00t_wbc/control/envs/g1/g1_env.py

@@ -222,11 +222,20 @@ def queue_action(self, action: Dict[str, any]):
         # Map action from joint order to actuator order
         body_actuator_q = self.robot_model.get_body_actuated_joints(action["q"])
 
+        # Compute gravity compensation torques if enabled
+        body_tau = np.zeros_like(body_actuator_q)
+        if self.enable_gravity_compensation and self.last_obs is not None:
+            current_q = self.last_obs["q"]
+            gravity_torques = self.robot_model.compute_gravity_compensation_torques(
+                current_q, joint_groups=self.gravity_compensation_joints
+            )
+            body_tau = self.robot_model.get_body_actuated_joints(gravity_torques)
+
         self.body().queue_action(
             {
                 "body_q": body_actuator_q,
                 "body_dq": np.zeros_like(body_actuator_q),
-                "body_tau": np.zeros_like(body_actuator_q),
+                "body_tau": body_tau,
             }
         )
 

tests/control/envs/g1/test_g1_env.py

@@ -0,0 +1,70 @@
+"""
+Integration tests for G1Env.
+
+Tests the gravity compensation fix from commit c28acee.
+"""
+
+import numpy as np
+import pytest
+from unittest.mock import MagicMock
+
+from gr00t_wbc.control.robot_model.instantiation import instantiate_g1_robot_model
+
+
+class TestG1EnvGravityCompensation:
+    """
+    Integration test for G1Env.queue_action() gravity compensation.
+
+    This test WILL FAIL if the fix is reverted (old code always sent body_tau=zeros).
+    """
+
+    @pytest.mark.parametrize("enable_gravity,expect_nonzero", [
+        (True, True),   # Gravity enabled → expect non-zero torques
+        (False, False), # Gravity disabled → expect zero torques
+    ])
+    def test_queue_action_gravity_compensation(self, enable_gravity, expect_nonzero):
+        """
+        Test that G1Env.queue_action() respects the gravity compensation flag.
+        """
+        from gr00t_wbc.control.envs.g1.g1_env import G1Env
+
+        robot_model = instantiate_g1_robot_model(waist_location="lower_body")
+
+        # Create minimal mock G1Env with real queue_action method
+        env = object.__new__(G1Env)
+        env.robot_model = robot_model
+        env.enable_gravity_compensation = enable_gravity
+        env.gravity_compensation_joints = ["arms"]
+        env.with_hands = False  # Skip hand commands in queue_action
+
+        # Set up last_obs with arm configuration
+        arm_indices = robot_model.get_joint_group_indices("arms")
+        q = np.zeros(robot_model.num_dofs)
+        for idx in arm_indices:
+            q[idx] = 0.3
+        env.last_obs = {"q": q}
+
+        # Mock safety_monitor
+        mock_safety = MagicMock()
+        mock_safety.handle_violations = lambda obs, action: {"action": action}
+        env.safety_monitor = mock_safety
+
+        # Capture what queue_action sends
+        captured_actions = []
+        mock_body = MagicMock()
+        mock_body.queue_action = lambda a: captured_actions.append(a)
+        env.body = lambda: mock_body
+
+        # Call actual queue_action
+        env.queue_action({"q": np.zeros(robot_model.num_dofs)})
+
+        # Verify
+        assert len(captured_actions) == 1
+        body_tau = captured_actions[0]["body_tau"]
+
+        if expect_nonzero:
+            assert not np.allclose(body_tau, 0), \
+                "BUG: body_tau is zeros when gravity compensation is enabled!"
+        else:
+            assert np.allclose(body_tau, 0), \
+                "body_tau should be zeros when gravity compensation is disabled"