[PlayerStage-Gazebo] Gazebo 0.9 Pioneer2dx unstable motion

[<jm....@al...>]

   Hi everyone,

   I'm having several problems when I launch gazebo with any world  
file, because the robot motion is not coherent. I mean, when I command  
velocity values just to go ahead, robot gets unbalance and after a few  
meters it falls over one side.

   I don't know if it's because of the pioneer2dx model or weights or  
physics or something like that... This is my world file:

<?xml version="1.0"?>

<gazebo:world
   xmlns:xi="http://www.w3.org/2001/XInclude"
   xmlns:gazebo="http://playerstage.sourceforge.net/gazebo/xmlschema/#gz"
   xmlns:model="http://playerstage.sourceforge.net/gazebo/xmlschema/#model"
   xmlns:sensor="http://playerstage.sourceforge.net/gazebo/xmlschema/#sensor"
   xmlns:window="http://playerstage.sourceforge.net/gazebo/xmlschema/#window"
   xmlns:param="http://playerstage.sourceforge.net/gazebo/xmlschema/#param"
   xmlns:body="http://playerstage.sourceforge.net/gazebo/xmlschema/#body"
   xmlns:geom="http://playerstage.sourceforge.net/gazebo/xmlschema/#geom"
   xmlns:joint="http://playerstage.sourceforge.net/gazebo/xmlschema/#joint"
    
xmlns:interface="http://playerstage.sourceforge.net/gazebo/xmlschema/#interface"
   xmlns:ui="http://playerstage.sourceforge.net/gazebo/xmlschema/#ui"
    
xmlns:rendering="http://playerstage.sourceforge.net/gazebo/xmlschema/#rendering"
    
xmlns:controller="http://playerstage.sourceforge.net/gazebo/xmlschema/#controller"
    
xmlns:physics="http://playerstage.sourceforge.net/gazebo/xmlschema/#physics"  
 >

   <verbosity>5</verbosity>

   <physics:ode>
     <stepTime>0.03</stepTime>
     <gravity>0 0 -9.8</gravity>
     <cfm>10e-5</cfm>
     <erp>0.3</erp>
     <updateRate>33.3333</updateRate>
   </physics:ode>

   <rendering:gui>
     <type>fltk</type>
     <size>800 600</size>
     <updateRate>20</updateRate>
     <pos>0 0</pos>

     <frames>
       <row height="100%">
         <camera width="100%">
           <xyz>0.35 -0.5 0.43</xyz>
           <rpy>0 14 111.5</rpy>
         </camera>
       </row>
     </frames>
   </rendering:gui>

   <rendering:ogre>
     <ambient>0.5 0.5 0.5 1.0</ambient>
     <sky>
       <material>Gazebo/CloudySky</material>
     </sky>
   </rendering:ogre>

    <!-- Ground Plane -->
   <model:physical name="plane1_model">
     <xyz>0 0 0</xyz>
     <rpy>0 0 0</rpy>
     <static>true</static>

     <body:plane name="plane1_body">
       <geom:plane name="plane1_geom">
         <normal>0 0 1</normal>
         <size>2000 2000</size>
         <segments>10 10</segments>
         <uvTile>100 100</uvTile>
         <material>Gazebo/Grey</material>
       </geom:plane>
     </body:plane>
   </model:physical>

   <model:physical name="cylinder1_model">
     <xyz>1 -1.5 0.5</xyz>
     <rpy>0.0 0.0 0.0</rpy>

     <body:cylinder name="cylinder1_body">
       <geom:cylinder name="cylinder1_geom">
         <size>0.5 1</size>
         <mass>1.0</mass>
         <visual>
           <mesh>unit_cylinder</mesh>
           <material>Gazebo/RustyBarrel</material>
         </visual>
       </geom:cylinder>
     </body:cylinder>
   </model:physical>

   <model:physical name="pioneer2dx_model1">
     <xyz>0 0 0.145</xyz>
     <rpy>0.0 0.0 0.0</rpy>
     <collide>all</collide>

     <model:physical name="laser">
       <xyz>0.15 0 0.18</xyz>

       <attach>
         <parentBody>chassis_body</parentBody>
         <myBody>laser_body</myBody>
       </attach>

       <include embedded="true">
         <xi:include href="models/sicklms200.model" />
       </include>
     </model:physical>
<!--
     <model:physical name="sonyvid30_model">
       <xyz>0.15 0 0.28</xyz>

       <attach>
         <parentBody>chassis_body</parentBody>
         <myBody>sonyvid30_body</myBody>
       </attach>

       <include embedded="true">
         <xi:include href="models/sonyvid30.model" />
       </include>
     </model:physical>
-->
     <!--
     The include should be last within a model. All previous statements
     will override those in the included file
     -->
     <include embedded="true">
       <xi:include href="models/pioneer2dx.model" />
     </include>
   </model:physical>

   <!-- White Directional light -->
   <model:renderable name="directional_white">
     <xyz>2.0 0 2.0</xyz>
     <enableGravity>false</enableGravity>

     <light>
       <type>spot</type>
       <spotCone>1000 1000 100</spotCone>
       <direction>-0.1 0 -0.9</direction>
       <diffuseColor>0.8 0.8 0.8</diffuseColor>
       <specularColor>0.1 0.1 0.1</specularColor>
       <range>10</range>

       <!-- Constant(0-1) Linear(0-1) Quadratic -->
       <attenuation>1.0 0.0 0</attenuation>
     </light>
   </model:renderable>

</gazebo:world>

   Thanks in advance,

   Julio