diff --git a/mimickit/engines/isaac_lab_engine.py b/mimickit/engines/isaac_lab_engine.py
index c87e1a9..8649d88 100644
--- a/mimickit/engines/isaac_lab_engine.py
+++ b/mimickit/engines/isaac_lab_engine.py
@@ -77,6 +77,7 @@ def __init__(self, config, num_envs, device, visualize):
         self._env_spacing = config["env_spacing"]
         self._obj_cfgs = []
         self._obj_control_modes = []
+        self._has_body_forces = []
         
         if ("control_mode" in config):
             self._control_mode = engine.ControlMode[config["control_mode"]]
@@ -483,6 +484,7 @@ def set_body_forces(self, env_id, obj_id, body_id, forces):
                                               env_ids=env_id,
                                               body_ids=sim_body_id,
                                               is_global=True)
+            self._has_body_forces[obj_id] = True
         return
     
     def get_obj_torque_limits(self, env_id, obj_id):
@@ -722,13 +724,37 @@ def _post_sim_step(self):
         return
 
     def _clear_forces(self):
-        for obj in self._objs:
-            if (obj.has_external_wrench):
-                forces = torch.zeros([1, 3], dtype=torch.float, device=self._device)
-                torques = torch.zeros([1, 3], dtype=torch.float, device=self._device)
-                obj.set_external_force_and_torque(forces=forces, torques=torques,
-                                                  positions=None, env_ids=None,
-                                                  body_ids=None, is_global=True)
+        num_envs = self.get_num_envs()
+        for obj_id, obj in enumerate(self._objs):
+            has_external_wrench = getattr(obj, "has_external_wrench", None)
+            if (has_external_wrench is None):
+                data = getattr(obj, "data", None)
+                if (data is not None):
+                    has_external_wrench = getattr(data, "has_external_wrench", None)
+
+            if isinstance(has_external_wrench, torch.Tensor):
+                has_external_wrench = bool(has_external_wrench.any().item())
+            elif isinstance(has_external_wrench, np.ndarray):
+                has_external_wrench = bool(has_external_wrench.any())
+
+            if (has_external_wrench is None):
+                has_external_wrench = self._has_body_forces[obj_id]
+
+            if (not has_external_wrench):
+                continue
+
+            obj_type = self.get_obj_type(obj_id)
+            if (obj_type == engine.ObjType.articulated):
+                num_bodies = int(self._body_order_sim2common[obj_id].numel())
+                forces = torch.zeros([num_envs, num_bodies, 3], dtype=torch.float, device=self._device)
+            else:
+                forces = torch.zeros([num_envs, 3], dtype=torch.float, device=self._device)
+
+            torques = torch.zeros_like(forces)
+            obj.set_external_force_and_torque(forces=forces, torques=torques,
+                                              positions=None, env_ids=None,
+                                              body_ids=None, is_global=True)
+            self._has_body_forces[obj_id] = False
         return
     
     def _validate_envs(self):
@@ -1075,6 +1101,7 @@ def _build_sim_tensors(self):
         num_envs = self.get_num_envs()
         num_objs = self.get_objs_per_env()
         self._objs_need_reset = torch.zeros([num_envs, num_objs], device=self._device, dtype=torch.bool)
+        self._has_body_forces = [False for _ in range(num_objs)]
         return
     
     def _filter_env_collisions(self):
@@ -1147,4 +1174,4 @@ def _on_keyboard_event(self, event):
             if (event.input in self._keyboard_callbacks):
                 callback = self._keyboard_callbacks[event.input]
                 callback()
-        return
\ No newline at end of file
+        return