Getting started

To get started with using sdu_controllers, you first need to install it on your system. See Installation.

First steps (defining a trajectory)

To run the joint-space motion controller in sdu_controllers, with the EUROfusion breeding blanket handling robot, you can use the pre-defined trajectory under:

examples/data/joint_trajectory_safe_bb.csv

which defines a trajectory that simulates the robot moving down into the vacuum vessel of the fusion reactor for breeding blanket removal. If you do not need a trajectory for the UR5e robot simply skip to next section with the joint-space motion controller.

If you want to try joint-space motion controller on a Universal Robots UR5e a trajectory must be generated first. Simply choose two arbitrary joint positions. In this example the robot is moved from the joint position \(q_{start}\) defined as:

\[q_{start} = [0^{\circ}, -90^{\circ}, -90^{\circ}, -90^{\circ}, 90^{\circ}, 0^{\circ}]\]

to the joint position \(q_{final}\) defined as:

\[q_{final} = [45^{\circ}, -120^{\circ}, -90^{\circ}, -60.0^{\circ}, 90^{\circ}, -45^{\circ}]\]

You can then run the provided Python script under scripts/generate_joint_trajectory.py to generate the joint trajectory like this:

cd scripts
python3 generate_joint_trajectory.py

Note

The generate_joint_trajectory.py Python script is using the jtraj() function from the Robotics toolbox for Python by Corke and Haviland [CH21], which uses a quintic (5th order) polynomial to create a smooth joint trajectory.

After running the script, the trajectory is available under examples/data/joint_trajectory_safe.csv. the trajectory should like like following on a UR5e manipulator:

With the trajectory generated we are now ready to run the joint-space motion control.