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The mobile system PRIAMOS. To eeciently integrate PRIAMOS' several sensor systems in order to not only reene geometric maps 19] but to generate maps containing topologic and semantic information has proven to be a very diicult task that demands learning capabilities. Therefore, the sophisticated user interface that has been developed for easy teleoperation and task speciication 13] will now be extended to provide examples that are used to let the robot learn exploration strategies. Since these exploration strategies require the coordinated use of the robot's sensor systems and its basic navigation skills (such as collision avoidance skills), this setting provides an immediate application for the multi-agent learning framework described within this paper. Consider the task of programming PRIAMOS to pass through a door. This task comprises activities such as approching the door, identiication of the door's state (opened, closed), and an exact positioning of the robot in front of the door. However, each of these activities, if performed manually, results in a single RCA. Within each R CA, the user operates the mobile platform and the vision system to achieve subgoals that can be automatically identiied. Each o f these subgoals, such a s door-detected, positioned, and through-door is the result of a speciic strategy and therefore located at the end of an RCS. Finally, we obtain for the door-passing task a sequence of subgoals to be achieved, the corresponding system states, and an indication of the agents that are responsible for achieving the subgoals.

The mobile system PRIAMOS. To eeciently integrate PRIAMOS' several sensor systems in order to not only reene geometric maps 19] but to generate maps containing topologic and semantic information has proven to be a very diicult task that demands learning capabilities. Therefore, the sophisticated user interface that has been developed for easy teleoperation and task speciication 13] will now be extended to provide examples that are used to let the robot learn exploration strategies. Since these exploration strategies require the coordinated use of the robot's sensor systems and its basic navigation skills (such as collision avoidance skills), this setting provides an immediate application for the multi-agent learning framework described within this paper. Consider the task of programming PRIAMOS to pass through a door. This task comprises activities such as approching the door, identiication of the door's state (opened, closed), and an exact positioning of the robot in front of the door. However, each of these activities, if performed manually, results in a single RCA. Within each R CA, the user operates the mobile platform and the vision system to achieve subgoals that can be automatically identiied. Each o f these subgoals, such a s door-detected, positioned, and through-door is the result of a speciic strategy and therefore located at the end of an RCS. Finally, we obtain for the door-passing task a sequence of subgoals to be achieved, the corresponding system states, and an indication of the agents that are responsible for achieving the subgoals.

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While distributed control architectures have many advantages over centralized ones, such as their inherent modularity and fault tolerance, a major problem of such architectures is to ensure the goal-oriented behaviour of the controlled system. This paper presents a framework within which the coordination skills required for goal-orientedness are le...

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... test bed for experiments using the multi-agent approach will be the mobile robot PRIAMOS 3], Fig. 7. PRIAMOS is a mobile system with three degrees of freedom, i.e. motion in longitudinal and transverse directions and rotation around the centre of the vehi- cle. A set of ultrasonic range sensors is mounted on a circle around the centre of the vehicle. It is also equipped with the active stereo-vision head KASTOR and a laser scanner ...

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