diff --git a/motrix_envs/src/motrix_envs/locomotion/go1/dreamwaq.py b/motrix_envs/src/motrix_envs/locomotion/go1/dreamwaq.py
index 7bca6e3..94fab4b 100644
--- a/motrix_envs/src/motrix_envs/locomotion/go1/dreamwaq.py
+++ b/motrix_envs/src/motrix_envs/locomotion/go1/dreamwaq.py
@@ -30,6 +30,19 @@ from motrix_envs.math import quaternion
 _SCENE_PRINTED = False
 
 
+def _sanitize_dof_pos(dof_pos: np.ndarray) -> np.ndarray:
+    """Make free-joint positions finite and guarantee normalized xyzw quaternions."""
+    clean = np.nan_to_num(
+        np.array(dof_pos, copy=True), nan=0.0, posinf=0.0, neginf=0.0
+    )
+    quat = clean[:, 3:7]
+    quat_norm = np.linalg.norm(quat, axis=1)
+    valid_quat = np.isfinite(quat_norm) & (quat_norm > 1e-6)
+    quat[valid_quat] /= quat_norm[valid_quat, np.newaxis]
+    quat[~valid_quat] = [0.0, 0.0, 0.0, 1.0]
+    return clean
+
+
 def _scene_file():
     """选择地形场景。DREAMWAQ_TERRAIN=flat|pyramid|flat_stairs。默认 FLAT。"""
     global _SCENE_PRINTED
@@ -353,22 +366,12 @@ class DreamWaQTask(Go1WalkTask):
             dv_clean[:, 6:] = np.nan_to_num(dv_clean[:, 6:], nan=0.0, posinf=0.0, neginf=0.0)
             data.set_dof_vel(dv_clean)
         dp = data.dof_pos
-        if np.any(~np.isfinite(dp)):
-            dp_clean = np.array(dp)
-            # 四元数 NaN → 整行替换为单位四元数 [0,0,0,1]
-            quat_nan_row = np.any(~np.isfinite(dp_clean[:, 3:7]), axis=1)
-            if np.any(quat_nan_row):
-                dp_clean[quat_nan_row, 3:7] = [0.0, 0.0, 0.0, 1.0]
-            # 关节位置 NaN → 0
-            dp_clean[:, 7:] = np.nan_to_num(dp_clean[:, 7:], nan=0.0, posinf=0.0, neginf=0.0)
-            data.set_dof_pos(dp_clean, self._model)
-        else:
-            quat_norm = np.linalg.norm(dp[:, 3:7], axis=1)
-            bad_quat = quat_norm < 1e-6
-            if np.any(bad_quat):
-                dp_clean = np.array(dp)
-                dp_clean[bad_quat, 3:7] = [0.0, 0.0, 0.0, 1.0]
-                data.set_dof_pos(dp_clean, self._model)
+        quat_norm = np.linalg.norm(dp[:, 3:7], axis=1)
+        needs_clean = np.any(~np.isfinite(dp)) or np.any(
+            ~np.isfinite(quat_norm) | (np.abs(quat_norm - 1.0) > 1e-4)
+        )
+        if needs_clean:
+            data.set_dof_pos(_sanitize_dof_pos(dp), self._model)
         obs = self._get_obs(data, state.info)
         obs = np.nan_to_num(obs, nan=0.0, posinf=0.0, neginf=0.0)
 
@@ -459,6 +462,10 @@ class DreamWaQTask(Go1WalkTask):
         else:
             done_idx = np.arange(num_reset)
 
+        if hasattr(self, "_action_buffer"):
+            self._action_buffer[done_idx] = 0.0
+            self._latency_steps[done_idx] = np.random.randint(0, 4, size=num_reset)
+
         # 游戏启发式地形课程（per-env，与上游一致）
         if not hasattr(self, '_terrain_origins'):
             all_origins = np.zeros((self._num_rows, self._num_cols, 2), dtype=np.float32)
diff --git a/motrix_envs/src/motrix_envs/locomotion/go1/walk_np.py b/motrix_envs/src/motrix_envs/locomotion/go1/walk_np.py
index 1694a98..39112bd 100644
--- a/motrix_envs/src/motrix_envs/locomotion/go1/walk_np.py
+++ b/motrix_envs/src/motrix_envs/locomotion/go1/walk_np.py
@@ -81,6 +81,19 @@ class Go1WalkTask(NpEnv):
     def get_dof_vel(self, data: mtx.SceneModel):
         return self._body.get_joint_dof_vel(data)
 
+    def _invalid_physics_state_mask(self, state: NpEnvState) -> np.ndarray:
+        invalid = super()._invalid_physics_state_mask(state)
+        dof_pos = np.asarray(state.data.dof_pos)
+        dof_vel = np.asarray(state.data.dof_vel)
+
+        quat_norm = np.linalg.norm(dof_pos[:, 3:7], axis=1)
+        invalid |= ~np.isfinite(quat_norm)
+        invalid |= np.abs(quat_norm - 1.0) > 1e-3
+        invalid |= np.any(np.abs(dof_pos[:, :3]) > 1e4, axis=1)
+        invalid |= np.any(np.abs(dof_pos[:, 7:]) > 20.0, axis=1)
+        invalid |= np.any(np.abs(dof_vel) > 1e3, axis=1)
+        return invalid
+
     def _init_buffer(self):
         cfg = self._cfg
         assert isinstance(cfg, Go1WalkNpEnvCfg)
diff --git a/motrix_envs/src/motrix_envs/np/env.py b/motrix_envs/src/motrix_envs/np/env.py
index 050d472..3cf6b75 100644
--- a/motrix_envs/src/motrix_envs/np/env.py
+++ b/motrix_envs/src/motrix_envs/np/env.py
@@ -201,6 +201,40 @@ class NpEnv(ABEnv):
             if self._physics_crash_count <= 3:
                 print(f"[WARN] physics crash #{self._physics_crash_count}: {e} — resetting {n} envs")
 
+    def _invalid_physics_state_mask(self, state: NpEnvState) -> np.ndarray:
+        """Return environments whose simulator state cannot be consumed safely."""
+        invalid = np.zeros(self._num_envs, dtype=bool)
+        for values in (state.data.dof_pos, state.data.dof_vel, state.data.actuator_ctrls):
+            array = np.asarray(values)
+            if array.ndim == 1:
+                array = array[:, np.newaxis]
+            invalid |= ~np.isfinite(array).all(axis=1)
+        return invalid
+
+    def _reset_invalid_physics_states(self) -> bool:
+        invalid = self._invalid_physics_state_mask(self._state)
+        if not np.any(invalid):
+            return False
+
+        self._state.terminated[invalid] = True
+        self._state.reward[invalid] = 0.0
+        # Make the backing SceneData safe before task-specific reset logic reads
+        # poses or curriculum statistics from the full batch.
+        self._state.data[invalid].reset(self._model)
+        if not hasattr(self, "_invalid_physics_state_count"):
+            self._invalid_physics_state_count = 0
+            self._invalid_physics_reset_events = 0
+        self._invalid_physics_state_count += int(invalid.sum())
+        self._invalid_physics_reset_events += 1
+        if self._invalid_physics_reset_events <= 10:
+            print(
+                f"[WARN] reset {int(invalid.sum())} invalid physics states "
+                f"(event={self._invalid_physics_reset_events}, "
+                f"total={self._invalid_physics_state_count})"
+            )
+        self._reset_done_envs()
+        return True
+
     def _prev_physics_step(self):
         state = self._state
         state.reward.fill(0.0)
@@ -218,6 +252,8 @@ class NpEnv(ABEnv):
         if getattr(self, "_physics_crashed_this_step", False):
             self._reset_done_envs()
             return self._state
+        if self._reset_invalid_physics_states():
+            return self._state
         self._state = self.update_state(self._state)
         self._state.info["steps"] += 1
         self._update_truncate()
diff --git a/motrix_envs/tests/test_dreamwaq_state_safety.py b/motrix_envs/tests/test_dreamwaq_state_safety.py
new file mode 100644
index 0000000..761a6a0
--- /dev/null
+++ b/motrix_envs/tests/test_dreamwaq_state_safety.py
@@ -0,0 +1,19 @@
+import numpy as np
+
+from motrix_envs.locomotion.go1.dreamwaq import _sanitize_dof_pos
+
+
+def test_sanitize_dof_pos_handles_zero_quaternion_with_nonfinite_joints():
+    dof_pos = np.zeros((2, 19), dtype=np.float32)
+    dof_pos[0, 3:7] = 0.0
+    dof_pos[0, 7] = np.inf
+    dof_pos[1, 3:7] = [0.0, 0.0, 0.5, 0.5]
+    dof_pos[1, 8] = np.nan
+
+    clean = _sanitize_dof_pos(dof_pos)
+
+    assert np.isfinite(clean).all()
+    np.testing.assert_allclose(clean[0, 3:7], [0.0, 0.0, 0.0, 1.0])
+    np.testing.assert_allclose(np.linalg.norm(clean[:, 3:7], axis=1), 1.0)
+    assert clean[0, 7] == 0.0
+    assert clean[1, 8] == 0.0