An Architecture for Autonomy

An autonomous robot o ers a challenging and ideal eld for the study of intelli gent architectures Autonomy within a rational behavior could be evaluated by the robot s e ectiveness and robustness in carrying out tasks in di erent and ill known environments It raises major requirements on the control architecture Furthermore a robot as a programmable machine brings up other architectural needs such as the ease and quality of its speci cation and programming This paper describes an integrated architecture allowing a mobile robot to plan its tasks taking into account temporal and domain constraints to perform corre sponding actions and to control their execution in real time while being reactive to possible events The general architecture is composed of three levels a decision level an execution level and a functional level The later is composed of modules that embed the functions achieving sensor data processing and e ector control The decision level is goal and event driven it may have several layers according to the ap plication their basic structure is a planner supervisor pair that enables to integrate deliberation and reaction The proposed architecture relies naturally on several representations program ming paradigms and processing approaches meeting the precise requirements speci ed for each level We developed proper tools to meet these speci cations and implement each level of the architecture IxTeT a temporal planner prs a procedural system for task re nement and supervision Kheops for the reactive control of the functional level and GenoM for the speci cation and integration of modules at that level Vali dation of temporal and logical properties of the reactive parts of the system through these tools are presented Instances of the proposed architecture have been already integrated into several indoor and outdoor robots Examples from real world experimentations are provided