How to fix bad odometry

edit

Hello,

I followed the steps on the ros wiki page to check my odometry and realized when rotating the robot it is really bad.

When rotating the scans don't match at all. So I tried to figure out where my problem is... but I could not find the paramters to change..

I am working with turtlebot3 and modified the wheel width. I think I got all paramters right, so they do fit to my robot. I changed paramters for turtlebot3 core in Arduino and the URDF model. My odometry still ist kind of bad... even when I change them to something obviously wrong the odometry still looks the same. So I must be missing something.

Where do I have to change parameters that affect my odometry?

Besides: I will try to simulate my model and look whether the paramters do fit there and my odometry looks right. As soon as I understood the gazebo thing I will give an update on that, but maybe somebody can help me so far?

I am really frustrated now cause I need to get things work by time.

Thank you! Laura

Here are my codes:

robot.urdf.xacro:

    <?xml version="1.0" ?>
<robot name="turtlebot3_waffle_pi" xmlns:xacro="http://ros.org/wiki/xacro">
  <xacro:include filename="$(find turtlebot3_description)/urdf/common_properties.xacro"/>
  <xacro:include filename="$(find turtlebot3_description)/urdf/turtlebot3_waffle_pi.gazebo.xacro"/>

  <link name="base_footprint"/>

  <joint name="base_joint" type="fixed">
    <parent link="base_footprint"/>
    <child link="base_link" />
    <origin xyz="0 0 0" rpy="0 0 0"/>
  </joint>

  <link name="base_link">
    <visual>
      <origin xyz="0 0 0" rpy="0 0 0"/>
      <geometry>
        <box size="0.52 0.50 1.20"/>
      </geometry>
      <material name="light_black"/>
    </visual>

    <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>
  </link>

  <joint name="sonar_bottom_right_joint" type="fixed">
    <parent link="base_link" />
    <child link="sonar_bottom_right_link" />
    <origin xyz="0.26 -0.16 -0.51" rpy="0 0 0" />
  </joint>

  <link name="sonar_bottom_right_link">
    <visual>
      <origin xyz="0 0 0" rpy="0 0 0"/>
      <geometry>
        <box size="0.005 0.05 0.05"/>
      </geometry>
      <material name="blue"/>
    </visual>

    <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>
  </link>

  <joint name="sonar_bottom_left_joint" type="fixed">
    <parent link="base_link" />
    <child link="sonar_bottom_left_link" />
    <origin xyz="0.26 0.16 -0 ...