| 1. |
- Kvarnström, Jonas, 1973-, et al.
(författare)
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Extending TALplanner with concurrency and resources
- 2000
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Ingår i: Proceedings of the 14th European Conference on Artificial Intelligence (ECAI). - Amsterdam, The Netherlands : IOS Press. - 4274903885 - 1586030132 ; , s. 501-505
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Konferensbidrag (refereegranskat)abstract
- We present TALplanner, a forward-chaining planner based on the use of domain-dependent search control knowledge represented as temporal formulas in the Temporal Action Logic (TAL). TAL is a narrative based linear metric time logic used for reasoning about action and change in incompletely specified dynamic environments. TAL is used as the formal semantic basis for TALplanner, where a TAL goal narrative with control formulas is input to TALplanner which then generates a TAL narrative that entails the goal formula. We extend the sequential version of TALplanner, which has previously shown impressive performance on standard benchmarks, in two respects: 1) TALplanner is extended to generate concurrent plans, where operators have varied durations and internal state; and 2) the expressiveness of plan operators is extended for dealing with several different types of resources. The extensions to the planner have been implemented and concurrent planning with resources is demonstrated using an extended logistics benchmark.
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| 2. |
- Doherty, Patrick, et al.
(författare)
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A Collaborative Framework for 3D Mapping using Unmanned Aerial Vehicles
- 2016
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Ingår i: PRIMA 2016: Principles and Practice of Multi-Agent Systems. - Cham : Springer Publishing Company. - 9783319448312 ; , s. 110-130
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Konferensbidrag (refereegranskat)abstract
- This paper describes an overview of a generic framework for collaboration among humans and multiple heterogeneous robotic systems based on the use of a formal characterization of delegation as a speech act. The system used contains a complex set of integrated software modules that include delegation managers for each platform, a task specification language for characterizing distributed tasks, a task planner, a multi-agent scan trajectory generation and region partitioning module, and a system infrastructure used to distributively instantiate any number of robotic systems and user interfaces in a collaborative team. The application focusses on 3D reconstruction in alpine environments intended to be used by alpine rescue teams. Two complex UAV systems used in the experiments are described. A fully autonomous collaborative mission executed in the Italian Alps using the framework is also described.
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| 3. |
- Doherty, Patrick, et al.
(författare)
-
HDRC3 - A Distributed Hybrid Deliberative/Reactive Architecture for Unmanned Aircraft Systems
- 2014
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Ingår i: Handbook of Unmanned Aerial Vehicles. - Dordrecht : Springer Science+Business Media B.V.. - 9789048197064 - 9789048197071 ; , s. 849-952
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- This chapter presents a distributed architecture for unmanned aircraft systems that provides full integration of both low autonomy and high autonomy. The architecture has been instantiated and used in a rotorbased aerial vehicle, but is not limited to use in particular aircraft systems. Various generic functionalities essential to the integration of both low autonomy and high autonomy in a single system are isolated and described. The architecture has also been extended for use with multi-platform systems. The chapter covers the full spectrum of functionalities required for operation in missions requiring high autonomy. A control kernel is presented with diverse flight modes integrated with a navigation subsystem. Specific interfaces and languages are introduced which provide seamless transition between deliberative and reactive capability and reactive and control capability. Hierarchical Concurrent State Machines are introduced as a real-time mechanism for specifying and executing low-level reactive control. Task Specification Trees are introduced as both a declarative and procedural mechanism for specification of high-level tasks. Task planners and motion planners are described which are tightly integrated into the architecture. Generic middleware capability for specifying data and knowledge flow within the architecture based on a stream abstraction is also described. The use of temporal logic is prevalent and is used both as a specification language and as an integral part of an execution monitoring mechanism. Emphasis is placed on the robust integration and interaction between these diverse functionalities using a principled architectural framework. The architecture has been empirically tested in several complex missions, some of which are described in the chapter.
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| 4. |
- Doherty, Patrick, et al.
(författare)
-
High-level Mission Specification and Planning for Collaborative Unmanned Aircraft Systems using Delegation
- 2013
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Ingår i: Unmanned Systems. - : World Scientific. - 2301-3850 .- 2301-3869. ; 1:1, s. 75-119
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Tidskriftsartikel (refereegranskat)abstract
- Automated specification, generation and execution of high level missions involving one or more heterogeneous unmanned aircraft systems is in its infancy. Much previous effort has been focused on the development of air vehicle platforms themselves together with the avionics and sensor subsystems that implement basic navigational skills. In order to increase the degree of autonomy in such systems so they can successfully participate in more complex mission scenarios such as those considered in emergency rescue that also include ongoing interactions with human operators, new architectural components and functionalities will be required to aid not only human operators in mission planning, but also the unmanned aircraft systems themselves in the automatic generation, execution and partial verification of mission plans to achieve mission goals. This article proposes a formal framework and architecture based on the unifying concept of delegation that can be used for the automated specification, generation and execution of high-level collaborative missions involving one or more air vehicles platforms and human operators. We describe an agent-based software architecture, a temporal logic based mission specification language, a distributed temporal planner and a task specification language that when integrated provide a basis for the generation, instantiation and execution of complex collaborative missions on heterogeneous air vehicle systems. A prototype of the framework is operational in a number of autonomous unmanned aircraft systems developed in our research lab.
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| 5. |
- Doherty, Patrick, et al.
(författare)
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Research with Collaborative Unmanned Aircraft Systems
- 2010
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Ingår i: Proceedings of the Dagstuhl Workshop on Cognitive Robotics. - : Leibniz-Zentrum für Informatik.
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Konferensbidrag (refereegranskat)abstract
- We provide an overview of ongoing research which targets development of a principled framework for mixed-initiative interaction with unmanned aircraft systems (UAS). UASs are now becoming technologically mature enough to be integrated into civil society. Principled interaction between UASs and human resources is an essential component in their future uses in complex emergency services or bluelight scenarios. In our current research, we have targeted a triad of fundamental, interdependent conceptual issues: delegation, mixed- initiative interaction and adjustable autonomy, that is being used as a basis for developing a principled and well-defined framework for interaction. This can be used to clarify, validate and verify different types of interaction between human operators and UAS systems both theoretically and practically in UAS experimentation with our deployed platforms.
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| 6. |
- Doherty, Patrick, 1957-, et al.
(författare)
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Robotics, Temporal Logic and Stream Reasoning
- 2013
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Ingår i: Proceedings of Logic for Programming Artificial Intelligence and Reasoning (LPAR), 2013.
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Konferensbidrag (refereegranskat)
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| 7. |
- Doherty, Patrick, 1957-, et al.
(författare)
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Tackling the qualification problem using fluent dependency constraints
- 1998
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Ingår i: Proceedings of the 5th International Workshop on Temporal Representation and Reasoning (TIME-98). - : IEEE Computer Society. - 0818684739 ; , s. 97-
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Konferensbidrag (refereegranskat)abstract
- The use of causal rules or fluent dependency constraints has proven to provide a versatile means of dealing with the ramification problem. In this paper we show how fluent dependency constraints together with the use of durational fluents can be used to deal with problems associated with action qualification. We provide both a \emph{weak} and \emph{strong} form of qualification and demonstrate the approach using an action scenario which combines solutions to the frame, ramification and qualification problems in the context of actions with duration, concurrent actions, non-deterministic actions and the use of both boolean and non-boolean fluents. The circumscription policy used for the combined problems is reducible to the 1st-order case. In addition, we demonstrate the use of a research tool VITAL, for querying and visualizing action scenarios.
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| 8. |
- Doherty, Patrick, 1957-, et al.
(författare)
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Tackling the Qualification Problem using Fluent Dependency Constraints: Preliminary Report
- 1997
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Recently, a great deal of progress has been made using nonmonotonic temporal logics to formalize reasoning about action and change. In particular, much focus has been placed on the proper representation of non-deterministic actions and the indirect effects of actions. One popular approach to representing the indirect effects of actions has been via the use of causal rules which in a more general sense can be viewed as fluent dependency constraints. Although fluent dependency constraints have been used primarily under a loose causal interpretation, we show that when interpreted in a broader sense they provide a flexible means for dealing with a number of other representational problems such as the qualification problem and the ramification constraints as qualification constraints problem, in addition to the standard ramification problem. More importantly, the use of fluent dependency constraints for different purposes does not involve additions to the base nonmonotonic temporal logic, TAL, used here, but simply the addition of several macro operators to an action language used to represent action scenarios or narratives. The payoff is that TAL has already been shown to offer a robust approach to representing action scenarios which permit incomplete specifications of both state and the timing of actions, non-deterministic actions, actions with duration, concurrent actions, use of both boolean and non-boolean fluents, and solutions to the frame and ramification problems for a wide class of action scenarios. In addition, all circumscribed action scenarios in these classes and the more general class involving qualification considered in this paper can be shown to be reducible to the first-order case. Finally, a restricted entailment method for this new class of scenarios is fully implemented. In the paper, we present a challenge example which incorporates all these features, propose a distinction between weak and strong qualification with a representation of both, and provide a visualization of the preferred entailments using a research tool VITAL for querying and visualizing action scenarios.
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| 9. |
- Doherty, Patrick, 1957-, et al.
(författare)
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(TAL) temporal action logics : Language specification and tutorial.
- 1998
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Ingår i: Electronic Transactions on Artifical Intelligence. - : Linköping University Electronic Press. - 1403-3534 .- 1403-3526. ; 2:3-4, s. 273-306
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this article is to provide a uniform, lightweight language specication and tutorial for a class of temporal logics for reasoning about action and change that has been developed by our group during the period 1994-1998. The class of logics are collected under the name TAL, an acronym for Temporal Action Logics. TAL has its origins and inspiration in the work with Features and Fluents (FF) by Sandewall, but has diverged from the methodology and approach through the years. We first discuss distinctions and compatibility with FF, move on to the lightweight language specication, and then present a tutorial in terms of an excursion through the different parts of a relatively complex narrative defined using TAL. We conclude with an annotated list of published work from our group. The article tries to strike a reasonable balance between detail and readability, making a number of simplications regarding narrative syntax and translation to a base logical language. Full details are available in numerous technical reports and articles which are listed in the final section of this article.
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| 10. |
- Doherty, Patrick, 1957-, et al.
(författare)
-
TALplanner : A temporal logic based forward chaining planner
- 2000
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Ingår i: Annals of Mathematics and Artificial Intelligence. - : Springer. - 1012-2443 .- 1573-7470. ; 30:1-4, s. 119-169
-
Tidskriftsartikel (refereegranskat)abstract
- We present TALplanner, a forward-chaining planner based on the use of domain-dependent search control knowledge represented as formulas in the Temporal Action Logic (TAL). TAL is a narrative based linear metric time logic used for reasoning about action and change in incompletely specified dynamic environments. TAL is used as the formal semantic basis for TALplanner, where a TAL goal narrative with control formulas is input to TALplanner which then generates a TAL narrative that entails the goal and control formulas. The sequential version of TALplanner is presented. The expressivity of plan operators is then extended to deal with an interesting class of resource types. An algorithm for generating concurrent plans, where operators have varying durations and internal state, is also presented. All versions of TALplanner have been implemented. The potential of these techniques is demonstrated by applying TALplanner to a number of standard planning benchmarks in the literature.
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