Copyright © 2001 IF AC
IFAC Conference on New Technologies for Computer Control
19-22 November 2001, Hong Kong
TOWARDS SELF-ORGANISING TIME-SENSITIVE CONTROL SYSTEM'S
SOFTWARE
Leo Motus and Merik Meriste#
Tallinn Technical University, leo.mo/us(ii,dcc.ttu.ee
tiTartu University, merik.meriste(wZlf.ee
Estonia
Abstract: The embedded computer applications are rapidly growing in numbers, in
complexity, and in dependability. This trend has been accompanied by shift of systems
building paradigm from individual algorithms to interacting computing entities (e.g.
agents, components, modules, etc). A number of studies focus on self-organising
capabilities of such entities (agents). Unfortunately for computer control systems, many
essential issues - such as, forced con currency, time awareness of theories and software,
and some others - have been almost neglected in the conventional theory. This paper
provides a superficial survey of evolution of software-intensive systems towards multi-
agent systems, lists subjectively some basic problems and achievements in developing
time-critical systems. The authors suggest that sufficiently good theoretical and
practical basis exists for building a test-bed that would assist in merging recent
development trends in software engineering and artificial intelligence, and enable
verification of time correctness of agent interaction. The test-bed would also assist in
developing a theory for quantitative asscssment of some properties of the evolving
structures, and enable step-wise extension and testing of the supported functions (as the
theoretical basis develops). COp'vright @ 2001 IFAC
Key words: multi-agent systems, time awareness, computational models, time models,
test-bed.
I. INTRODUCTION
Everyday life in the contemporary world depends
heavily on software-intensive time-, safety-, and
security-critical systems. It is not easy to manage a
day without using (the services) of the following
devices, or systems - vehicles, telephones, audio-
video equipment, security systems, medical devices,
transport system, air conditioning systems. Some
other examples are less visible, or not yet functioning
- for instance, distributed computer control systems,
mobile multi-robot systems, automatic motorways,
human and computer system collaboration in
problem sol ving.
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Many of the listed software-intensive applications
may have dynamically changing goals, should
preferably be able to modify dynamically their
configuration - most of these changes are invoked
either by the environment they are embedded in, or
by the subjective will of their users (or the goal
function). Some systems must have fault-tolerant
and/or safety-critical design and implementation and,
in addition, must be (strictly) time-sensitive so as to
cope with their goals and imposed constraints.
The design and implementation methods have passed
a remarkable evolution to enable the building of such