diff --git a/urdf/diffbot_description.urdf.xacro b/urdf/diffbot_description.urdf.xacro
index 728c270..9b27b67 100644
--- a/urdf/diffbot_description.urdf.xacro
+++ b/urdf/diffbot_description.urdf.xacro
@@ -163,7 +163,7 @@
     <joint name="${prefix}laser_joint" type="fixed">
         <parent link="${prefix}chassis"/>
         <child link="${prefix}laser_frame"/>
-        <origin xyz="-0.07 0 0.10" rpy="0 0 ${pi}"/>
+        <origin xyz="${chassis_length/2 -0.07} 0 0.10" rpy="0 0 ${pi}"/>
     </joint>
 
     <link name="${prefix}laser_frame">