ROS Services, Actions, Publishers and Subscribers for Raspberry Pi 4, ROS Melodic oriented to Servos and robot arms

ROS services, actions, publishers and subscribers build over a RBPi 4, using Python and C++

I'm building some stuff based on servos controlled by a PCA9685 connected to a Raspberry Pi running ROS Melodic. The ROS server is an nvidia Jetson Xavier AGX, but could be any board or virtual machine.

First attempts were using an arduino + rosservial, but the limited capacity and poor documentation for implementing services and actions made me to desist to use it. Later I review several robotic arms and I saw that any of them were based on raspberry.

This is a project on development, started on July 2020.