Study On Software Modularization And Workflow Modeling Of Autonomous Underwater Vehicle

As the evolution of Intelligence and function of Autonomous Underwater Vehicle (AUV),traditional developing pattern is now insufficient to deal with its sophisticated softwaresystem. With a disordered software system, it is complicated to reconfigure and upgrade thesystem, for all of its units are interdependent. Additionally, the lack of a consistent standardleads to an inefficient system which is nearly impossible for reprocess and reuse.A modular and distributed software system called “MASS”(Moudlar Architecture forSoftware System) is presented. MASS was designed with modularization and standardizationin mind, allowing it to be flexible, reusable and easy for programming. Developers couldimplement their own module according to the interface of MASS, making use of existingmodules, and build an AUV control system as a combination of these units. By analyzing itstopology, communication method, information transmit mechanism, system management anduser interface, the property of its structure and function is expatiated. The developing processthat implemented MASS system under embedded operating system VxWorks6.7has alsobeen recorded.To find a convenient and functional way to describe and manage tasks that AUVperforms, a practical task model named “task workflow” was designed by improving thetraditional workflow theory. As its foundations, Petri net and workflow model are introducedbriefly, and their limitations are pointed out. The task system based on task workflow has agraphical picture, a text mode description, and a task management system build under MASSwhich could execute tasks and modify task flow online.A semi-physical simulation platform with mobile robot has been established and it canbe used to test MASS system and its task system. A chemical plume tracing experiment hassucceeded on this platform with MASS and task workflow system.Trial and examination proved the usability and reliability of MASS, which will benefitthe development of AUV software system. Practice shows that task workflow is easy forprogramming and it is an ideal model for task modeling and management.