An Embedded Workflow Framework for Flexible Robotic Devices

This paper describes the design and implementation of an open source embedded workflow framework (EMWF). By providing a language for specifying embedded workflow processes and light weight engines for executing and managing them, EMWF enables us to design and build service robots and assistive robotic devices on workflow-based architecture. The embedded process definition language supported by EMWF is called SISARL-XPDL. It is a subset of the standard process definition language XPDL (XML Process Definition Language) augmented with elements that are essential for smart embedded devices but not offered by XPDL. The SISARL-XPDL preprocessor translates augmented elements into either directives for the engine or compound built-in activities defined in terms of standard XPDL. EMWF provides two workflow engines, for Linux and Windows CE platforms. Both are written in C in order to keep the memory footprint and runtime overhead of the engine small. We use EMWF as a test bed for experimentation with the workflow approach and evaluation of workflow-based design. Copyright @ April 2008 T. S. Chou, Y. C. Wang, and J. W. S. Liu are affiliated with Institute of Information Science, Academia Sinica.Taiwan. Their email addresses are {tschou, wych, janeliu}@iis.sinica.edu.tw S. Y. Chang, M. K. Ouyang, Y. F. Lu, C. S. Shih and T. W. Kuo are affiliated with Department of Computer Science and Information Engineering, National Taiwan University, Taiwan. M. K. Ouyang’s email address is ouyang@iis.sinica.edu.tw, and the email addresses of Y. F. Lu, C. S. Shih and T. W. Ku are {d93023, cshih, ktw}@csie.ntu.edu.tw J. S. Hu is affiliated with Electrical and Control Engineering Department, National Chiao-Tung University, Taiwan. His email address is jshu@cn.nctu.edu.tw