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diff --git a/urdf/signs/dae/alvar3_neg_1.dae b/urdf/signs/dae/alvar3_neg_1.dae
new file mode 100644
index 0000000000000000000000000000000000000000..298be625173191262a64ead4bef943bd0ed9f45c
--- /dev/null
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+        </source>
+        <vertices id="image-VERTEX">
+          <input semantic="POSITION" source="#image-POSITION"/>
+        </vertices>
+        <triangles count="2" material="Material #36">
+          <input semantic="VERTEX" offset="0" source="#image-VERTEX"/>
+          <input semantic="NORMAL" offset="1" source="#image-Normal0"/>
+          <input semantic="TEXCOORD" offset="2" set="0" source="#image-UV0"/>
+          <p> 0 0 0 1 1 1 3 2 3 3 3 3 2 4 2 0 5 0</p>
+        </triangles>
+      </mesh>
+    </geometry>
+  </library_geometries>
+  <library_visual_scenes>
+    <visual_scene id="" name="">
+      <node name="image" id="image" sid="image">
+        <matrix sid="matrix">1 0 0 0 0 0 1 0 0 -1 0 0 0 0 0 1</matrix>
+        <instance_geometry url="#image-lib">
+          <bind_material>
+            <technique_common>
+              <instance_material symbol="Material #36" target="#Material #36"/>
+            </technique_common>
+          </bind_material>
+        </instance_geometry>
+        <extra>
+          <technique profile="FCOLLADA">
+            <visibility>1</visibility>
+          </technique>
+        </extra>
+      </node>
+      <extra>
+        <technique profile="MAX3D">
+          <frame_rate>30</frame_rate>
+        </technique>
+        <technique profile="FCOLLADA">
+          <start_time>0</start_time>
+          <end_time>3.333333</end_time>
+        </technique>
+      </extra>
+    </visual_scene>
+  </library_visual_scenes>
+  <scene>
+    <instance_visual_scene url="#"></instance_visual_scene>
+  </scene>
+</COLLADA>
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diff --git a/urdf/signs/dae/png/alvar3_neg_1.png b/urdf/signs/dae/png/alvar3_neg_1.png
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