MAGUI - A Multi-Agent Graphical User Interface

Abstract: Man-machine interfaces are a very important part of any computer application. A good human interface must be friendly and effective providing a good interaction between the human operator and the application. Human interfaces for multi-agent systems (MAS) are specially complex because the multiple requirements of this kind of architectures where the human operator is interacting with a multitude of different autonomous agents often characterized by a great dynamics. The presence of more than one user in the system, with similar or with different competencies is another interesting problem that is quite realistic in many applications of MAS. In this paper, the particular requirements of user interfaces for multi-agent systems are discussed and a multi-agent graphical user interface in the framework of a multi-user multi-agent system is presented. Keywords: Multi-agent systems, man-machine interface, user modelling. I. Introduction User interface design is often a large, complex and difficult task. A 1992 study found that 48% of the code of applications and 50% of the development time is dedicated to the user interface portion [1]. Nowadays, graphical user interfaces (GUI) are almost universal. Studies from 1993 indicate that 97% of all software development on UNIX involved a GUI [2]. In fact, the user interface is usually a crucial part of any commercial product. Because it is the front end of the application it usually must be easy to learn, use and perform the functions their users want [3]. Poor human interfaces degrade human-computer interaction increasing mistakes and user frustration and, as a consequence, degrading system performance and reliability. Also, because this is the portion of code directly in contact with the user, the only way to get good results is to design and re-design it iteratively in direct cooperation with the final users. Only if this process is followed the product can be correctly adapted to the real requirements, despite the fact that the implementation becomes harder. Unfortunately, all these difficulties are present, and some of them aggravated when developing user interfaces for multi-agent systems (MAS). In addition to the usual requirements of any other user-interface, in multi-agent systems, several factors introduce a higher degree of difficulty to the GUI designer specially when considering fine-grained MAS: • a large number of agents can be present on the system trying to communicate with the user. In order to overcome this problem the human interface must provide a way for the user to choose among the various agents those that justify attention with the higher priority. • the possible heterogeneity can introduce difficulties on the communication process between the agents and the user. Whenever we consider that a multi-agent system can contain agents representing different companies, reflecting different commercial “cultures”, the problem of language translation (both at syntactical and semantic levels) becomes important. • the unpredictability associated with this kind of systems introduces particular problems, specially when the Multi-Agent Systems are supposed to have high dynamics, with agents appearing and going on runtime. The motivation for the development of a graphical user interface especially dedicated to multi-agent systems environment was mainly the MACIV project [4]. The aim of this project is the development of a MAS for distributed resource management on civil construction companies. The large number of software agents involved in this particular application, the presence of different companies and the variety and number of users interacting with the system lead us to the development of MAGUI. MAGUI is a completely dynamic GUI, which means that all its configuration is done at run-time by the agents themselves. This way, whenever the agents become active they can make their own registration on the GUI to obtain a “communication channel” to the user and “unregister” when they have their job done. In order to support all the unpredictability inherent to such a system, nothing is pre-determined in what concerns to interface menus. All