From its home page:

XOberon/PowerPC is a hard real-time operating system (HRTOS), deployed for high-end mechatronic products control. It has been developed at the Institute of Robotics, Swiss Federal Institute of Technology, Zurich. XOberon is loosely based on the Oberon System, and it is written in the Oberon-2 programming language. XOberon in its most recent incarnation takes advantage of the computational power of the PowerPC processor architecture.

The goal of XOberon is about providing a framework for non-computer-scientists, looking for a rapid application development (RAD) tool for programming embedded applications.