Integration of a Contextual Observation System in a Multi-Process Architecture for Autonomous Vehicles

We propose a software layered architecture for autonomous vehicles whose efficiency is driven by pull-based acquisition of sensor data. This multiprocess software architecture, to be embedded into the control loop of these vehicles, includes a Belief-Desire-Intention agent that can consistently assist the achievement of intentions. Since driving on roads implies huge dynamic considerations, we tackle both reactivity and context awareness considerations on the execution loop of the vehicle. While the proposed architecture gradually offers 4 levels of reactivity, from arch-reflex to the deep modification of the previously built execution plan, the observation module concurrently exploits noise filtering and introduces frequency control to allow symbolic feature extraction while both fuzzy and first order logic management are used to enforce consistency and certainty over the context information properties. The presented use-case, the daily delivery of a network of pharmacy offices by an autonomous vehicle taking into account contextual (spatio-temporal) traffic features, shows the efficiency and the modularity of the architecture, as well as the scalability of the reaction levels

A multi-agent approach for ambient system design : a formal model incorporating planning and learning

Ce travail présente une architecture logicielle concrète dédiée aux besoins et caractéristiques des systèmes d'Intelligence Ambiante (AmI). Le modèle comportemental proposé, appelé Higher-order Agent (HoA), capture simultanément l'évolution de l'état mental de l'agent ainsi que l'état de son plan d'actions. Les expressions du plan sont écrites et composées en utilisant un langage algébrique formel, nommé AgLOTOS. Les plans sont construits automatiquement et à la volée, comme un système de processus concurrents, déduits des intentions de l'agent et de ses préférences d'exécution. Basé sur une sémantique de plans et d'actions concurrentes, un service de guidance est aussi proposé afin d'assister l'agent dans le choix de ses prochaines exécutions. Cette guidance permet d'améliorer la satisfaction des intentions de l'agent au regard des plans concurrents possibles et en fonction du contexte actuel de l'agent. La "localité" et le "temps" étant considérés comme des informations contextuelles clés dans l'activité de l'agent, nous les prenons en compte au travers de deux fonctions utilitaires originales conçues à partir des expériences des exécutions d'action et pouvant être combinées suivant les préférences stratégiques de l'agent. La structure compositionnelle des expressions AgLOTOS est mise à profit pour permettre des révisions ciblées du plan de l'agent, Les révisions des sous-plans sont donc réalisées automatiquement en fonction des mises à jour apportées aux intentions, tout en maintenant la consistance du comportement de l'agent. Un cas d'étude est développé afin de montrer comment l'agent peut agir, même s'il subit des changements inattendus de son contexte, en fonction de ses expériences passées qui révèlent certains cas de d'échecs.This work presents a concrete software architecture dedicated to ambient intelligence (AmI) features and requirements. The proposed behavioral model, called Higher-order Agent (HoA) captures the evolution of the mental representation of the agent and the one of its plan simultaneously. Plan expressions are written and composed using a formal algebraic language, namely AgLOTOS, so that plans are built automatically and on the fly, as a system of concurrent processes. Due to the compositional structure of AgLOTOS expressions, the updates of sub-plans are realized automatically accordingly to the revising of intentions, hence maintaining the consistency of the agent. Based on a specific semantics, a guidance service is also proposed to assist the agent in its execution. This guidance allows to improve the satisfaction of the agent's intentions with respect to the possible concurrent plans and the current context of the agent. Adopting the idea that "location" and "time" are key stones information in the activity of the agent, we show how to enforce guidance by ordering the different possible plans. As a major contribution, we demonstrate two original utility functions that are designed from the past-experiences of the action executions, and that can be combined accordingly to the current balance policy of the agent. A use case scenario is developed to show how the agent can act, even if it suffers from unexpected changes of contexts, it does not have many experiences and whose past experiences reveals some failure cases

Une approche multi-agent pour la conception de systèmes d'intelligence ambiante : un modèle formel intégrant planification et apprentissage

This work presents a concrete software architecture dedicated to ambient intelligence (AmI) features and requirements. The proposed behavioral model, called Higher-order Agent (HoA) captures the evolution of the mental representation of the agent and the one of its plan simultaneously. Plan expressions are written and composed using a formal algebraic language, namely AgLOTOS, so that plans are built automatically and on the fly, as a system of concurrent processes. Due to the compositional structure of AgLOTOS expressions, the updates of sub-plans are realized automatically accordingly to the revising of intentions, hence maintaining the consistency of the agent. Based on a specific semantics, a guidance service is also proposed to assist the agent in its execution. This guidance allows to improve the satisfaction of the agent's intentions with respect to the possible concurrent plans and the current context of the agent. Adopting the idea that "location" and "time" are key stones information in the activity of the agent, we show how to enforce guidance by ordering the different possible plans. As a major contribution, we demonstrate two original utility functions that are designed from the past-experiences of the action executions, and that can be combined accordingly to the current balance policy of the agent. A use case scenario is developed to show how the agent can act, even if it suffers from unexpected changes of contexts, it does not have many experiences and whose past experiences reveals some failure cases.Ce travail présente une architecture logicielle concrète dédiée aux besoins et caractéristiques des systèmes d'Intelligence Ambiante (AmI). Le modèle comportemental proposé, appelé Higher-order Agent (HoA), capture simultanément l'évolution de l'état mental de l'agent ainsi que l'état de son plan d'actions. Les expressions du plan sont écrites et composées en utilisant un langage algébrique formel, nommé AgLOTOS. Les plans sont construits automatiquement et à la volée, comme un système de processus concurrents, déduits des intentions de l'agent et de ses préférences d'exécution. Basé sur une sémantique de plans et d'actions concurrentes, un service de guidance est aussi proposé afin d'assister l'agent dans le choix de ses prochaines exécutions. Cette guidance permet d'améliorer la satisfaction des intentions de l'agent au regard des plans concurrents possibles et en fonction du contexte actuel de l'agent. La "localité" et le "temps" étant considérés comme des informations contextuelles clés dans l'activité de l'agent, nous les prenons en compte au travers de deux fonctions utilitaires originales conçues à partir des expériences des exécutions d'action et pouvant être combinées suivant les préférences stratégiques de l'agent. La structure compositionnelle des expressions AgLOTOS est mise à profit pour permettre des révisions ciblées du plan de l'agent, Les révisions des sous-plans sont donc réalisées automatiquement en fonction des mises à jour apportées aux intentions, tout en maintenant la consistance du comportement de l'agent. Un cas d'étude est développé afin de montrer comment l'agent peut agir, même s'il subit des changements inattendus de son contexte, en fonction de ses expériences passées qui révèlent certains cas de d'échecs

A Reinforcement Learning Integrating Distributed Caches for Contextual Road Navigation

International audienceDue to contextual traffic conditions, the computation of optimized or shortest paths is a very complex problem for both drivers and autonomous vehicles. This paper introduces a reinforcement learning mechanism that is able to efficiently evaluate path durations based on an abstraction of the available traffic information. The authors demonstrate that a cache data structure allows a permanent access to the results whereas a lazy politics taking new data into account is used to increase the viability of those results. As a client of the proposed learning system, the authors consider a contextual path planning application and they show in addition the benefit of integrating a client cache at this level. Our measures highlight the performance of each mechanism, according to different learning and caching strategies

Integration of a Contextual Observation System in a Multi-Process Architecture for Autonomous Vehicles

We propose a software layered architecture for autonomous vehicles whose efficiency is driven by pull-based acquisition of sensor data. This multiprocess software architecture, to be embedded into the control loop of these vehicles, includes a Belief-Desire-Intention agent that can consistently assist the achievement of intentions. Since driving on roads implies huge dynamic considerations, we tackle both reactivity and context awareness considerations on the execution loop of the vehicle. While the proposed architecture gradually offers 4 levels of reactivity, from arch-reflex to the deep modification of the previously built execution plan, the observation module concurrently exploits noise filtering and introduces frequency control to allow symbolic feature extraction while both fuzzy and first order logic management are used to enforce consistency and certainty over the context information properties. The presented use-case, the daily delivery of a network of pharmacy offices by an autonomous vehicle taking into account contextual (spatio-temporal) traffic features, shows the efficiency and the modularity of the architecture, as well as the scalability of the reaction levels

Time petri nets with action duration: A true concurrency real-time model

The design of real-time systems needs a high-level specification model supporting at the same time timing constraints and actions duration. The authors introduce in this paper an extension of Petri Nets called Time Petri Nets with Action Duration DTPN where time is associated with transitions. In DTPN, the firing of transitions is bound to a time interval and transitions represent actions which have explicit durations. The authors give an operational semantics for DTPN in terms of Durational Action Timed Automata DATA. DTPN considers both timing constraints and durations under a true-concurrency semantics with an aim of better expressing concurrent and parallel behaviours of real-time systems.42628

Dealing with temporal failure in ambient systems: a dynamic revision of plans

This paper presents AgLOTOS as an algebraic language dedicated to the specification of agent plans in ambient systems taking into account timing constraints. It offers a rich and modular approach to express and compose elementary plans in order to execute them concurrently. We show how a plan is built automatically as a system of concurrent processes from the belief-desire-intention attitudes of the agent. The AgLOTOS semantics allows to deal with possible plan execution failures, caused by the passing of time for performance of actions. In this situation, this information is captured at the mental process level allowing to update the agent mental state. Moreover, the associated semantics accords with the possibility of revising the agent plan, as the set of intentions changes.6