Hi guys,

I am using a modified version of turtlebot3 and tried to make a quiet simple model in gazebo but when opening it in gazebo its always slipping and/or rotating a bit.

I first tried to have two caster wheels (which is how it really looks though) but decided to first try it with one.. cause that is hard enough for the beginnging.

I hope somebody can help me with this!

Here is my urdf:

<?xml version="1.0" ?>

<collision>
  <origin xyz="0 0 0" rpy="0 0 0"/>
  <geometry>
    <box size="0.52 0.50 1.20"/>
  </geometry>
</collision>

<inertial>
  <origin xyz="0 0 0" rpy="0 0 0"/>
  <mass value="20.00e+00"/>
  <inertia ixx="3" ixy="0" ixz="0"
           iyy="2.82" iyz="0"
           izz="0.83" />
</inertial>

<collision>
  <origin xyz="0 0 0" rpy="0 0 0"/>
  <geometry>
    <box size="0.005 0.05 0.05"/>
  </geometry>
</collision>

<inertial>
  <origin xyz="0 0 0" />
  <mass value="1.8498940e-02" />
  <inertia ixx="0.1175580e-05" ixy="-3.2369783e-11" ixz="-4.9381719e-09"
           iyy="0.1192413e-05" iyz="-0.4400107e-11"
           izz="0.0712558e-05" />
  </inertial>

<collision>
  <origin xyz="0 0 0" rpy="0 0 0"/>
  <geometry>
    <box size="0.005 0.05 0.05"/>
  </geometry>
</collision>

<inertial>
  <origin xyz="0 0 0" />
  <mass value="1.8498940e-02" />
  <inertia ixx="0.1175580e-05" ixy="-3.2369783e-11" ixz="-4.9381719e-09"
           iyy="0.1192413e-05" iyz="-0.4400107e-11"
           izz="0.0712558e-05" />
  </inertial>

<collision>
  <origin xyz="0 0 0" rpy="0 0 0"/>
  <geometry>
    <cylinder length="0.018" radius="0.033"/>
  </geometry>
</collision>

<inertial>
  <origin xyz="0 0 0" />
  <mass value="2.8498940e-02" />
  <inertia ixx="1.1175580e-05" ixy="-4.2369783e-11" ixz="-5.9381719e-09"
           iyy="1.1192413e-05" iyz="-1.4400107e-11"
           izz="2.0712558e-05" />
  </inertial>

<collision>
  <origin xyz="0 0 0" rpy="0 0 0"/>
  <geometry>
    <cylinder length="0.018" radius="0.033"/>
  </geometry>
</collision>

<inertial>
  <origin xyz="0 0 0" />
  <mass value="2.8498940e-02" />
  <inertia ixx="1.1175580e-05" ixy="-4.2369783e-11" ixz="-5.9381719e-09"
           iyy="1.1192413e-05" iyz="-1.4400107e-11"
           izz="2.0712558e-05" />
  </inertial>

<collision>
  <origin xyz="0 0 0" rpy="0 0 0"/>
  <geometry>
    <sphere radius="0.033"/>
  </geometry>
</collision>

<inertial>
  <origin xyz="0 0 0" />
  <mass value="2.8498940e-02" />
  <inertia ixx="0.001" ixy="0.0" ixz="0.0"
           iyy="0.001" iyz="0.0"
           izz="0.001" />
  </inertial>

<collision>
  <origin xyz="0.015 0 -0.0065" rpy="0 0 0"/>
  <geometry>
    <cylinder length="0.0315" radius="0.055"/>
  </geometry>
</collision>

<inertial>
  <mass value="0.114" />
  <origin xyz="0 0 0" />
  <inertia ixx="0.001" ixy="0.0" ixz="0.0"
           iyy="0.001" iyz="0.0"
           izz="0.001" />
</inertial>

and my gazebo.xacro for friction:

<?xml version="1.0"?>

Gazebo/DarkGrey

0.1 0.1 500000.0 10.0 0.001 0.1 1 0 0 Gazebo/FlatBlack

0.1 0.1 500000.0 10.0 0.001 0.1 1 0 0 Gazebo/FlatBlack

false 0.1 0.1 1000000.0 100.0 0.001 1.0 Gazebo/FlatBlack

true $(arg imu_visual) Gazebo/Grey

cmdvel odom odom world true basefootprint false true true false 30 wheelleftjoint wheelrightjoint 0.287 0.066 1 10 na

true imulink imulink imu imuservice 0.0 200 gaussian 0.0 2e-4 <biasmean>0.0000075 0.0000008 0.0 1.7e-2 0.1 0.001

Gazebo/FlatBlack 0 0 0 0 0 0 $(arg laservisual) <updaterate>5 360 1 0.0 6.28319 0.120 3.5 0.015 gaussian 0.0 0.01 scan base_scan