An Architecture for Autonomy

Abstract

An autonomous robot offers a challenging and ideal field for the study of intelligent architectures. Autonomy within a rational be havior could be evaluated by the robot's effectiveness and robust ness in carrying out tasks in different and ill-known environments. It raises major requirements on the control architecture. Further more, a robot as a programmable machine brings up other archi tectural needs, such as the ease and quality of its specification and programming. This article describes an integrated architecture that allows a mobile robot to plan its tasks—taking into account temporal and domain constraints, to perform corresponding actions and to con trol their execution in real-time—while being reactive to possible events. The general architecture is composed of three levels: a de cision level, an execution level, and a functional level. The latter is composed of modules that embed the functions achieving sensor- data processing and effector control. The decision level is goal and event driven, and it may have several layers, according to the application; their basic structure is a planner/supervisor pair that enables the architecture to integrate deliberation and reaction. The proposed architecture relies naturally on several representa tions, programming paradigms, and processing approaches, which meet the precise requirements that are specified for each level. The authors have developed proper tools to meet these specifications and implement each level of the architecture: a temporal planner, IxTeT; a procedural system for task refinement and supervision, PRS; Kheops for the reactive control of the functional level, and GenoM for the specification and integration of modules at that level Validation of the temporal and logical properties of the reactive parts of the system, through these tools, are presented. Instances of the proposed architecture have been integrated into several indoor and outdoor robots. Examples from real-world ex perimentations are provided and analyzed.

Intelligent Supervision for Robust Plan Execution

“…Previous works in literature have faced this problem by endowing the plan executor (e.g., a mobile robot) with some form of autonomous behavior. For instance, the control architectures discussed in [7,8,10] support the robot's autonomy by means of three layers of control: the highest one is devoted to the decisional aspects and it is typically based on one (or even more) (re)planning module(s).…”

“…The second level of the architecture is the FL, which, from our point of view, is an abstraction of the rover's hardware able to match the actions issued by the Supervisor into lower level commands for the rover's actuators. In doing so, the FL may exploit services such as localization, obstacle avoidance, short range path planning, path following (see [7,8]). …”

Control of autonomous robot behavior using data filtering through adaptive resonance theory

“…These operations are described by a control architecture defining the elements required to achieve the desired behavior, especially in the following areas [1]:…”

Autonomous Learning Architecture for Environmental Mapping

“…In the AI literature there are several classical architecture approaches, for instance, NASREM (Albus et al, 1989), LAAS (Alami et al, 1998), Subsumption (Brooks, 1986) and so on. However, there is no widely accepted theory of architecture design that can be used to prove that one design is better than another (Russel and Norvig, 1995).…”