From 7e35ca01218b2c780d4dbc379a6ca8f47482fb0b Mon Sep 17 00:00:00 2001
From: Gary Servin <garyservin@gmail.com>
Date: Tue, 5 Aug 2014 11:26:14 -0400
Subject: [PATCH] Fixed empty world and gps parameters

---
 cvg_sim_gazebo/launch/empty_world.launch           | 14 +++++++++-----
 .../urdf/quadrotor_sensors.urdf.xacro              |  4 ++--
 2 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/cvg_sim_gazebo/launch/empty_world.launch b/cvg_sim_gazebo/launch/empty_world.launch
index 95cc036..be7f105 100644
--- a/cvg_sim_gazebo/launch/empty_world.launch
+++ b/cvg_sim_gazebo/launch/empty_world.launch
@@ -1,8 +1,12 @@
+<?xml version="1.0"?>
 <launch>
-  <param name="/use_sim_time" value="true" />
-  <node name="empty_world_server" pkg="gazebo" type="gazebo" args="$(find cvg_sim_gazebo)/worlds/empty.world" respawn="false" output="screen">
+  <!-- We resume the logic in empty_world.launch, changing only the name of the world to be launched -->
+  <include file="$(find gazebo_ros)/launch/empty_world.launch">
+  </include>
 
-  </node>
-  <node name="gazebo_gui" pkg="gazebo" type="gui" respawn="false" output="screen"/>
-</launch>
 
+  <!-- Spawn simulated quadrotor uav -->
+  <include file="$(find cvg_sim_gazebo)/launch/spawn_quadrotor.launch" >
+    <arg name="model" value="$(find cvg_sim_gazebo)/urdf/quadrotor_sensors.urdf.xacro"/> 
+  </include>
+</launch>
diff --git a/cvg_sim_gazebo_plugins/urdf/quadrotor_sensors.urdf.xacro b/cvg_sim_gazebo_plugins/urdf/quadrotor_sensors.urdf.xacro
index dc6cbdb..a6d6c9a 100644
--- a/cvg_sim_gazebo_plugins/urdf/quadrotor_sensors.urdf.xacro
+++ b/cvg_sim_gazebo_plugins/urdf/quadrotor_sensors.urdf.xacro
@@ -56,13 +56,13 @@ xmlns:xacro="http://ros.org/wiki/xacro"
         <bodyName>base_link</bodyName>
         <topicName>fix</topicName>
         <velocityTopicName>fix_velocity</velocityTopicName>
-        <drift>5.0 5.0 5.0</drift>
         <referenceLatitude>-25.291084</referenceLatitude>
         <referenceLongitude>-57.629623</referenceLongitude>
         <referenceAltitude>136</referenceAltitude>
+        <drift>5.0 5.0 5.0</drift>
         <gaussianNoise>0.1 0.1 0.1</gaussianNoise>
         <velocityDrift>0 0 0</velocityDrift>
-        <velocityGaussianNoise>0.1 0.1 0.1</velocityGaussianNoise>
+        <velocityGaussianNoise>0.0 0.0 0.0</velocityGaussianNoise>
       </plugin>
 
       <plugin name="quadrotor_groundtruth_sim" filename="libgazebo_ros_p3d.so">