swerve-teleop-simulation

Here we are moving swerve drive using teleop in simulation using swerve_steering_controller.

You can find some info about the controller here.

Steps to implement teleop in simulation -

You need Ubuntu 20.04 and ros noetic.
Download ros_controllers package from here from noetic-devel branch because this controller is developed in ros-noetic. Solve catkin_make errors (if any).
Create your own urdf. I have added a custom made urdf 'swerve_description' in this repository and also added whole cad in .stl format. I extracted that urdf from Autodesk Fusion360. Add your package in same workspace in which you have downloded ros_controller package.

Add robotNamespace and robotSimType parameters in gazebo_ros_control plugin (if not present)

  <gazebo>
    <plugin name="gazebo_ros_control" filename="libgazebo_ros_control.so">
      <robotNamespace>/</robotNamespace>
      <robotSimType>gazebo_ros_control/DefaultRobotHWSim</robotSimType>
    </plugin>
  </gazebo>

Add following gazebo plugin

  <gazebo>
    <plugin name="ground_truth" filename="libgazebo_ros_p3d.so">
      <alwaysOn>true</alwaysOn>
      <updateRate>50.0</updateRate>
      <gaussianNoise>0.01</gaussianNoise>
      <bodyName>base_footprint</bodyName>
      <topicName>odomw</topicName>
    </plugin>
  <gazebo>

Now inside urdf check the transmissions. The hardwareInterface parameter inside joint of wheels should be VelocityJointInterface and for holders it should be PositionJointInterface.

e.g. for wheel's joint
```
 <hardwareInterface>hardware_interface/VelocityJointInterface</hardwareInterface>
```
for holder's joint
```
 <hardwareInterface>hardware_interface/PositionJointInterface</hardwareInterface>
```
If you are having any doubt, check our swerve.trans file.
Make the changes in launch file 'robot.launch' inside swerve_steering_controller/test/launch according to your urdf. We have added our robot.launch file too.
Change the parameters in 'ros_controllers.yaml' inside swerve_steering_controller/test/config. We have added that file too.
Now you are ready to launch 'robot.launch' from swerve_steering_controller/test/launch.
In order to run teleop_twist_keyboard you need to change topic name inside teleop_twist_keyboard.py from 'cmd_vel' to 'swerve_steering_controller/cmd_vel'. We have done that and added teleop_twist_keyboard.py file here.
Now, first launch 'robot.launch' then run 'teleop_twist_keyboard.py' and you can see your swerve drive moving.

The video recording of our execution is available here.

avdhootu27/swerve-teleop-simulation

swerve-teleop-simulation

Steps to implement teleop in simulation -