The Robot Software Communications Architecture (RSCA): QoS-Aware Middleware for Networked Service Robots

The ubiquitous robot companion (URC) project has been recently launched in Korea with an aim of putting networked service robots into practical use in residential environments by overcoming technical challenges of home service robots. Embedded middleware is surely one of such challenges since it has to deal with many critical and difficult problems such as real-time guarantees and software reconfigurability on a heterogeneous, distributed mechatronics system. In this paper, we adopt middleware called SCA from the software defined radio domain and extend it for use in URC robots. We call the end result robot software communications architecture (RSCA). The RSCA provides a standard operating environment for robot applications together with a framework that expedites the development of such applications. The operating environment is comprised of a real-time operating system, communication middleware, and deployment middleware, which collectively form a hierarchical structure. Specifically, the RSCA deployment middleware supports the reconfiguration of component-based robot applications including installation, creation, start, stop, tear-down, and un-installation. Since the original SCA lacks real-time guarantees and QoS support, we have significantly extended it while maintaining backward compatibility so that URC robot developers can use existing SCA tools. We have fully implemented RSCA and performed measurements to quantify its run-time performance. Our implementation clearly shows the viability of RSCA