diff --git a/src/turtlebot_description/urdf/turtlebot.urdf.xacro b/src/turtlebot_description/urdf/turtlebot.urdf.xacro
index 6e2de4d..544dd13 100644
--- a/src/turtlebot_description/urdf/turtlebot.urdf.xacro
+++ b/src/turtlebot_description/urdf/turtlebot.urdf.xacro
@@ -212,7 +212,7 @@
         <origin xyz="-0.177 0.064 -0.004" rpy="-1.57 0 0"/>
     </joint> -->
 
-    <joint name="caster__joint" type="fixed">
+    <joint name="caster_joint" type="fixed">
         <parent link="base_link"/>
         <child link="caster_link"/>
         <origin xyz="-0.177 0.064 -0.004" rpy="-1.57 0 0"/>
diff --git a/src/turtlebot_description/urdf/turtlebot_gazebo.xacro b/src/turtlebot_description/urdf/turtlebot_gazebo.xacro
index 112e455..3e7f4eb 100644
--- a/src/turtlebot_description/urdf/turtlebot_gazebo.xacro
+++ b/src/turtlebot_description/urdf/turtlebot_gazebo.xacro
@@ -32,18 +32,7 @@
         <material>Gazebo/FlatBlack</material>
     </gazebo>
     
-    <gazebo reference="caster_back_right_link">
-        <mu1>0.1</mu1>
-        <mu2>0.1</mu2>
-        <kp>1000000</kp>
-        <kd>100</kd>
-        <minDepth>0.001</minDepth>
-        <maxVel>1</maxVel>
-        <fdir1>1 0 0</fdir1>
-        <material>Gazebo/FlatBlack</material>
-    </gazebo>
-
-    <gazebo reference="caster_back_left_link">
+    <gazebo reference="caster_link">
         <mu1>0.1</mu1>
         <mu2>0.1</mu2>
         <kp>1000000</kp>
@@ -82,4 +71,33 @@
             <hardwareInterface>hardware_interface/VelocityJointInterface</hardwareInterface>
         </actuator>
     </transmission>
+
+    <gazebo reference="base_scan">
+
+        <sensor name="laser" type="ray">
+            <pose> 0 0 0 0 0 0 </pose>
+            <visualize>true</visualize>
+            <update_rate>10</update_rate>
+            <ray>
+                <scan>
+                    <horizontal>
+                        <samples>360</samples>
+                        <min_angle>-3.14</min_angle>
+                        <max_angle>3.14</max_angle>
+                    </horizontal>
+                </scan>
+                <range>
+                    <min>0.3</min>
+                    <max>12</max>
+                </range>
+            </ray>
+            <plugin name="laser_controller" filename="libgazebo_ros_ray_sensor.so">
+                <ros>
+                    <argument>~/out:=scan</argument>
+                </ros>
+                <output_type>sensor_msgs/LaserScan</output_type>
+                <frame_name>laser_frame</frame_name>
+            </plugin>
+        </sensor>
+    </gazebo>
 </robot>
\ No newline at end of file