More changes to Laser Mapping and old exercise migration

Overview

This week I worked on adding an extra map choice for the laser mapping exercise and started migrating an old exercise from Gazebo Classic to Gazebo Harmonic.

Adding a new world to laser mapping

Since the current map takes around 2 hours to fully cover, I created a new, smaller map so the students can test their solutions in an environment that is faster to cover and check if your solution works.

Most of this week work on this was creating the world and implementing it in Robotics Academy, the reference map for the frontend has yet to be implemented.

Migration of Basic Vacuum Cleaner exercise

The other thing I was doing this week was starting the migration of the Basic Vacuum Cleaner exercise to Gazebo Harmonic. The exercise should work the same but running on the newer gazebo version.

The models used in this exercise are house_int2, which is the model of the entire house in the exercise, and roombaROS, which is the model of the vacuum cleaner.

I started with the house_int2 model, barely any changes were made to make it work in harmonic at first, but I quickly discovered a problem. This model, like many others, implement custom textures by material scripts. This, however, is not supported in Gazebo Harmonic, at least for complex textures, it’s only supported for basic colors, so the wood textures that some furniture had is replaced with solid colors like orange.

There are other material properties that aren’t supported like transparency. In order to fix this, we need to completely remake the models using meshes, one way to do it is remaking the models in Blender and exporting them to sdf using a custom plugin called sdf_exporter.py. That way, we can implement the textures inside the meshes, which is supported by Gazebo Harmonic.

The next objective is to migrate the roombaROS model to harmonic. The model itself doesn’t have any problems but I have to update the plugins used by ros that implements the sensors and actuators, since they are different in Gazebo Harmonic.