Honor URDF collision visualization option

source/extensions/isaacsim.asset.exporter.urdf/isaacsim/asset/exporter/urdf/converter/link_reader.py

@@ -60,15 +60,16 @@ class LinkData:
     collisions: list[CollisionData] = field(default_factory=list)
 
 
-def read_link(prim: Usd.Prim) -> LinkData:
+def read_link(prim: Usd.Prim, visualize_collision_meshes: bool = False) -> LinkData:
     """Read all URDF link data from a rigid body prim.
 
     Classifies children as visuals or collisions based on CollisionAPI
-    and purpose attributes.  Geometry origins are set to identity here;
+    and purpose attributes. Geometry origins are set to identity here;
     they are recomputed by the orchestrator using URDF frames.
 
     Args:
         prim: USD prim with RigidBodyAPI.
+        visualize_collision_meshes: Whether collision geometry should also be emitted as visual geometry.
 
     Returns:
         LinkData with inertial, visuals, and collisions populated.
@@ -102,7 +103,7 @@ def read_link(prim: Usd.Prim) -> LinkData:
                     )
                 )
 
-            if is_visual:
+            if (is_visual and not is_collision) or (is_collision and visualize_collision_meshes):
                 mat_name = _get_bound_material_name(child)
                 link.visuals.append(
                     VisualData(
@@ -134,7 +135,7 @@ def _iter_geometry_children(prim: Usd.Prim) -> Generator[Usd.Prim, None, None]:
 
     Traverses the full subtree under the rigid body prim using
     Usd.TraverseInstanceProxies so that instanced geometry (common in
-    Isaac Sim assets) is found.  Stops descending into child rigid bodies
+    Isaac Sim assets) is found. Stops descending into child rigid bodies
     and joints to stay within the current link's scope.
 
     For instance proxies, reads from the prototype to ignore overrides.

source/extensions/isaacsim.asset.exporter.urdf/isaacsim/asset/exporter/urdf/converter/usd_to_urdf.py

@@ -165,7 +165,7 @@ def convert(
 
         for link_prim in desc.ordered_links:
             link_path = str(link_prim.GetPath())
-            link_data = read_link(link_prim)
+            link_data = read_link(link_prim, visualize_collision_meshes=self._visualize_collision_meshes)
             link_name_map[link_path] = link_data.name
 
             # Recompute geometry origins and export meshes
@@ -554,7 +554,7 @@ def _build_actuator_map(root_prim: Usd.Prim) -> dict[str, Usd.Prim]:
 
     Traverses the subtree under *root_prim* looking for ``MjcActuator``
     prims and resolves their ``mjc:target`` relationship to identify the
-    target joint.  Returns an empty dict when no actuators are present.
+    target joint. Returns an empty dict when no actuators are present.
 
     Args:
         root_prim: Robot root prim.

source/extensions/isaacsim.asset.exporter.urdf/isaacsim/asset/exporter/urdf/tests/test_collision_visualization_option.py

@@ -0,0 +1,31 @@
+# SPDX-FileCopyrightText: Copyright (c) 2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+"""Regression coverage for the URDF collision-visualization option."""
+
+import omni.kit.test
+from isaacsim.asset.exporter.urdf.converter.link_reader import read_link
+from pxr import Usd, UsdGeom, UsdPhysics
+
+
+class TestCollisionVisualizationOption(omni.kit.test.TestCase):
+    def _create_link_with_collision_cube(self) -> Usd.Prim:
+        stage = Usd.Stage.CreateInMemory()
+        link = UsdGeom.Xform.Define(stage, "/Robot/link").GetPrim()
+        UsdPhysics.RigidBodyAPI.Apply(link)
+        collision = UsdGeom.Cube.Define(stage, "/Robot/link/Collision").GetPrim()
+        UsdPhysics.CollisionAPI.Apply(collision)
+        return link
+
+    def test_collision_geometry_is_not_visual_by_default(self) -> None:
+        link = read_link(self._create_link_with_collision_cube())
+
+        self.assertEqual(len(link.collisions), 1)
+        self.assertEqual(len(link.visuals), 0)
+
+    def test_collision_geometry_is_visual_when_requested(self) -> None:
+        link = read_link(self._create_link_with_collision_cube(), visualize_collision_meshes=True)
+
+        self.assertEqual(len(link.collisions), 1)
+        self.assertEqual(len(link.visuals), 1)
+        self.assertEqual(link.visuals[0].name, link.collisions[0].name)