Showing papers by "Daniele Nardi published in 2002"
TL;DR: The usefulness of MKNF-DLs for a formal characterization of a wide variety of nonmonotonic features that are both commonly available inframe-based systems, and needed in the development of practical knowledge-based applications: defaults, integrity constraints, role, and concept closure are shown.
Abstract: We present description logics of minimal knowledge and negation as failure (MKNF-DLs), which augment description logics with modal operators interpreted according to Lifschitz's nonmonotonic logic MKNF. We show the usefulness of MKNF-DLs for a formal characterization of a wide variety of nonmonotonic features that are both commonly available inframe-based systems, and needed in the development of practical knowledge-based applications: defaults, integrity constraints, role, and concept closure. In addition, we provide a correct and terminating calculus for query answering in a very expressive MKNF-DL.
267 citations
TL;DR: A self-localization method based on the Hough transform for matching a geometric reference map with a representation of range information acquired by the robot’s sensors that is adequate for indoor office-like environments, especially for those environments that can be suitably represented by a set of segments.
47 citations
07 Aug 2002
TL;DR: The design and implementation of a biped locomotion strategy for the robot Sony ERS-210 (AIBO) is described, which fully exploit the double support phase, in which the robot has both feet on the ground, in order to achieve the correct take-off conditions for performing the single support phase.
Abstract: We describe the design and implementation of a biped locomotion strategy for the robot Sony ERS-210 (AIBO). Being designed for quadruped gaits, this robot has several limitations which make biped locomotion a challenging task, such as passive feet, a high barycenter in the erect posture, and relatively weak actuators. We have therefore chosen to fully exploit the double support phase, in which the robot has both feet on the ground, in order to achieve the correct take-off conditions for performing the single support phase. During the latter, the mechanism motion is essentially uncontrolled but can be predicted and planned using a simple equivalent mechanical system. Both simulation and experimental results show the positive outcome of our study.
39 citations
07 Aug 2002
TL;DR: This paper presents an extension of Hough localization which is able to deal with the global localization problem, in which the robot does not know its initial position in the environment.
Abstract: Knowing the position of a mobile robot in the environment in which it operates is an important element for effectively accomplishing complex tasks requiring autonomous navigation. Among several existing techniques for robot self-localization, a new approach called Hough localization was proposed for map matching in the Hough domain, that turned out to be reliable and efficient for position tracking in polygonal environments. In this paper we present an extension of Hough localization which is able to deal with the global localization problem, in which the robot does not know its initial position in the environment.
26 citations
01 Jan 2002
TL;DR: For an effective application of hybrid approaches a crucial role is played by the organization of information among the layers, which is heavily influenced both by the features of the robotic platform and by the problem at hand.
Abstract: One of the major challenges in the design of robots that can act autonomously in unstructured, dynamic and unpredictable environments is the ability to achieve desired goals by executing complex high-level plans, while promptly reacting to unpredicted situations and adjusting the behavior based on new knowledge acquired through the sensors during task execution. Several years of research have focussed on the software architecture by exploiting the sense-plan-act (or deliberative) approach [9], the behavior-based (or reactive) one [1], as well as hybrid architectures [3] which combine advantages of both reactivity and deliberation. However, for an effective application of hybrid approaches a crucial role is played by the organization of information among the layers, which is heavily influenced both by the features of the robotic platform and by the problem at hand.
14 citations
08 Jul 2002
TL;DR: The goal of the project is to design tools to monitor the situation after a large-scale disaster, with a particular focus on the task on situation assessment and high-level information fusion, as well as on the issues that arise in coordinating the agent actions based on the acquired information.
Abstract: The goal of the project, which is currently under development, is to design tools to monitor the situation after a large-scale disaster, with a particular focus on the task on situation assessment and high-level information fusion, as well as on the issues that arise in coordinating the agent actions based on the acquired information. The development environment is based on the RoboCup-Rescue simulator: a simulation environment used for the RoboCup-Rescue competition, allowing for the design of both agents operating in the scenario and simulators for modeling various aspects of the situation including the graphical interface to monitor the disaster site. Our project is focussed on three aspects: modeling in the simulator a scenario devised from the analysis of a real case study; an extension of the simulator enabling for the experimentation of various communication and information fusion schemes; a framework for developing agents that are capable of constructing a global view of the situation and of distributing specific information, to other agents in order to drive their actions.
13 citations
01 Jan 2002
7 citations
01 Jan 2002
TL;DR: This work considers an extended notion of plan by admitting a simple class of cycles that arise from the attempt to recover from the failure states originated by sensing actions, to address the problem of generating plans that handle a form of synchronization based on the recognition of specific situations through sensing actions.
Abstract: In this paper we present the recent developments of the approach to the design of Cognitive Robots (i.e. robots whose actions are driven by a formally developed theory of action), that are capable of performing tasks in a coordinated way. The logic of actions that we adopt is an epistemic dynamic logic, where it is possible to derive acyclic branching plans (branches corresponding to sensing actions), including primitive parallel actions. In the present work, we consider an extended notion of plan by admitting a simple class of cycles that arise from the attempt to recover from the failure states originated by sensing actions. The proposed extension allows us to address the problem of generating plans that handle a form of synchronization based on the recognition of specific situations through sensing actions, including forms of coordination required in a multi-robot scenario.
2 citations
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TL;DR: This work is a team description where it will be highlighted what the team development effort focused on: the realization of a motion module, the realized of a vision module and the improvement of the plans which characterize the different robot roles.
Abstract: The SPQR (Soccer Player Quadruped Robots, but also Senatus PopolusQue Romanus) team participated for the second time to Sony Legged League in RoboCup 2001. This work is a team description where it will be highlighted what the team development effort focused on: the realization of a motion module, the realization of a vision module and the improvement of the plans which characterize the different robot roles.
1 citations
01 Jan 2002
TL;DR: By exploiting the previous experience in designing and developing soccer robots, this paper has developed innovative techniques for vision, localization, planning and coordination in the S.P.R.Q. Wheeled team of soccer robots.
Abstract: This paper presents the design and implementation issues that have been addressed for the realization of the S.P.Q.R. Wheeled team of soccer robots. The team is formed by "senior" soccer robots that have participated to previous RoboCup competitions as well as by new robots developed for completing the team. By exploiting our previous experience in designing and developing soccer robots, we have developed innovative techniques for vision, localization, planning and coordination.