Design of Database Node Module in three-layered architecture for tele-operator

In this paper, our proposed software architecture for tele-operated systems such as planetary exploration rovers is introduced firstly. The architecture modularizes each function as a software module, makes advanced extendibility and flexible task management by connecting with a database via network and managing them, and, as a result, improves efficiency in development and operation stages of systems. Those functions of the architecture is realized with DNM (Database Node Module), therefore we discuss and design it. DNMs are databases to which all the functional modules on system are connected, and they require functions, which manage the connections of modules and control data flows and execution-sequences. The management function of module connections improves the system maintenancebility by applying a virtual attachment facility. The other function performing the data flows of modules is realized by a shared memory, and it is also in charge of improvement of communication speed and visualizing communication. Its system performance with DNM was evaluated with a transmission speed and a system load by a simulation, and stability assessment was proceeded by using an actual robot. According to experimental results, DNM and its system showed us their performance designed and required in this paper, and the validities of the architecture and DNM have been indicated.