Real life implementations of distributed swarm robotics are rare. The standardization of a general purpose swarm robotics platform could greatly accelerate swarm robotics towards real life implementations. The SwarmUS platform is an open-source hardware and software on-board embedded system designed to be added onto existing robots while providing them with swarm features, thus proposing a new take on the platform standardization problem. These features include a distributed relative localization system based on Ultra-Wideband, a local communication system based on Wi-Fi and a distributed coordination system based on the Buzz programming language between robots connected within a SwarmUS platform. Additionally, a human-swarm interaction mobile application and an emulation of the platform in the Robot Operating System (ROS) is presented. Finally, an implementation of the system was realized and tested on two types of robots : a TurtleBot3 Burger and two Pioneer 2DX.