Based-on the work of: https://github.com/andresaraque/centauri6dof.git
Special thanks to @andresaraque, @franciscopedroza030595 and @vromerocano for their contribution to open-source movement in Colombia. More on that here: https://www.uao.edu.co/lo-uao-de-la-semana/centauri-el-robot-de-los-autonomos/
In order to play with the robot, it needs to be launched in Gazebo firstly:
ros2 launch centauri_kinematics sim_kinematics.launch.py
Said launch file contains several nodes and commands to launch the robot in Gazebo, as well to activate a kinematics, a gripper and get-home configuration servers, respectively.
No matter in what configuration is robot itself, it's possible for getting it into the home configuration using the following command:
ros2 launch centauri_kinematics sim_kinematics.launch.py
For the forward kinematics, the Product of Exponential method was selected due to its capability to deal with link offsets easily. On the other hand, for the inverse kinematics, a hybrid numerical method between Newton-Raphson and Descendent Gradiante was implemented, due to the former's fast convergence and the latter's stable solutions.
Due to robot kinematics' nature, a ROS2 service pipeline was implemented for getting to a desired one-goal position. Also, as this package contains a simulation-only manipulator, the ros2_control package was implemented to control each joint's position.
First, the robot needs to be launched in Gazebo:
ros2 launch centauri_kinematics sim_kinematics.launch.py
Second, the robot needs a request in order to get to a desired goal:
ros2 run centauri_kinematics kinematics_client.py 0.351 -0.288 0.351
In this case: x = 0.351 , y = -0.288 and z = 0.351. Here are other suggested goals to try:
- Goal 1: 0.161 -0.288 0.547
- Goal 2: 0.351 0.001 0.405
In case the kinematics solution needs to be checked through TF2, use the following command:
ros2 run tf2_ros tf2_echo base_footprint tool_center
Just like before, the robot needs to be launched in the Gazebo enviroment:
ros2 launch centauri_kinematics sim_kinematics.launch.py
To close the gripper for grasping tasks, use the following command:
ros2 run centauri_description gripper_client.py on
However, the same node can used to open the gripper for the same purposes:
ros2 run centauri_description gripper_client.py off
Finally, here's a demo of Centauri's current state:
