diff --git a/urdf/diffbot_description.urdf.xacro b/urdf/diffbot_description.urdf.xacro
index 79247fc..9c73b65 100644
--- a/urdf/diffbot_description.urdf.xacro
+++ b/urdf/diffbot_description.urdf.xacro
@@ -197,7 +197,7 @@
 
     <!-- laser_joint -->
     <joint name="${prefix}laser_joint" type="fixed">
-      <origin xyz="${base_length /2 +0.015 - base_offset} 0 -${z_offset}" rpy="0 0 0"/>
+      <origin xyz="${base_length /2 +0.015 - base_offset} 0 ${z_offset * -1}" rpy="0 0 0"/>
       <parent link="${prefix}base_link" />
       <child link="${prefix}laser_link" />
       <axis xyz="0 0 1"/>