DSAAV - A distributed software architecture for autonomous vehicles

Autonomous Underwater Vehicle (AUV) technology has matured over the past few decades but commercial AUVs today remain complex, proprietary and expensive. Modularity in AUVs at a software, electronics and mechanical level allows users to configure AUVs for specific missions by only including the required components. With multiple base AUVs, users may easily configure heterogeneous teams of AUVs for collaborative missions. Modular AUVs are also easier to maintain. We expect that open-architecture AUVs with open software/hardware interfaces, changeable modules and open source components will become widely available in the future. However AUV configuration management and module compatibility are issues that arise with modularity. An initiative at the Acoustic Research Laboratory (ARL) of the National University of Singapore (NUS) has yielded an open- architecture collaborative prototype AUV known as STARFISH. The software components in this AUV are based on the DSAAV architecture. DSAAV has been designed ground up with modular AUVs in mind. In a DSAAV compliant AUV, each module provides a uniform software interface that other AUV modules can access. This interface allows configuration of the module, logging of critical information, discovery of services, access to sensor & actuator services, health monitoring and automated software update functionality. The interface is rich in functionality, yet light weight and portable to ensure that even low power micro-controllers can easily implement it. DSAAV can be implemented on any underlying communication backbone such as Ethernet, UDP/IP, etc. The software components running under DSAAV are independent of the underlying communication backbone and function without change in various AUVs and simulation environments. In this paper, we describe the basic philosophy and concepts behind DSAAV. We also outline the Application Programming Interface (API) for DSAAV compliant systems and describe its key functionality. It is our hope that DSAAV will be adopted and extended by other AUVs in the future.