+<?xml version="1.0" ?>
+<sdf version="1.4" >
+ <world name="default" >
+ <include>
+ <uri>model://ground_plane</uri>
+ </include>
+ <include>
+ <uri>model://sun</uri>
+ </include>
+ <include>
+ <uri>model://gas_station</uri>
+ <name>gas_station</name>
+ <pose>-2.0 7.0 0 0 0 0</pose>
+ </include>
+ <physics type='ode'>
+ <max_step_size>0.02</max_step_size>
+ <real_time_update_rate>50</real_time_update_rate>
+ </physics>
+ </world>
+</sdf>