Luca Bogoni

Interactive recognition and representation of functionality

Abstract Functionality of an object defines its applicability to a task, In this paper, we introduce a representation for functionality and present a methodology for its recovery. In addition, we introduce force-shape maps as means to integrate and classify the recovered functionality, Since functionality describes an interaction, the representation for an object must include not only its intrinsic (material) but also its functional (how it is used) properties. In order to recover the functionality of an object, we have developed a formalism based on discrete event system theory and on the paradigm of active perception. This formalism allows us to express an investigating task in the form of a finite automaton for controlling and observing the interactions in our task. Our current investigation focuses on manipulatory interactions, and thus far, the functionality of piercing. We envision an expandable system having at its disposal a score of investigative procedures and through them to be able to classify and recognize an object based on its functional attributes.

Quantitative and qualitative measures for the evaluation of the superquadric models

Evaluation criteria for superquadric models recovered from the range data discussed. Arguments are presented to support the authors belief that both quantitative and qualitative measures are required in order to evaluate a superquadric fit. The concept of superquadric contraction and dilation is introduced and used to derive a novel interpretation of the modified superquadric inside-outside function in terms of contraction/expansion factor. The same concept also gives a close initial guess for the numerical procedure computing the minimum Euclidean distance of a point from a superquadric model. The minimum Euclidean distance map is introduced as a qualitative criterion for interpretation of fit. View-dependent qualitative measures like the contour-difference map and the Z-distance map are shown to be essential for the complete evaluation of the models. Analytical solution and techniques for the contour generator on superquadric models are presented. Finally, examples of real objects are given to generate the measures.<<ETX>>

Application of discrete events systems for modeling and controlling robotic agents

In this paper we present a framework for modeling behaviors and tasks for heterogeneous robotic agents. For this purpose we have adopted a formalism from the discrete events systems (DES) theory. We distinguish two kinds of scenarios. In the first one, reactive behaviors of mobile agents directly connect observations with actions. The overall objective is to achieve controllability of the system which is composed from modular components operating in parallel. In the second one, observations are implicitly connected with actions and the objective is to design an observer for manipulatory tasks which would guarantee the tasks observability. The use of the DES formalism allows one to describe complex interactions between different components in a systematic fashion and guarantee some control-theoretic properties. We demonstrate our approach by presenting examples of navigation, obstacle avoidance, piercing and picking.<<ETX>>

Investigating functionality: the case of piercing operation

The application of tools by artificial systems depends on the ability to recognize an object as having a particular function as well as on the ability to express the functional interaction. This paper focuses on the operation of piercing as means of investigating the issue of functional representation. The operation is expressed using a formalism, based on discrete event system (DES) theory and on the paradigm of active perception. The visual and tactile data acquired during piercing motor actions performed with a robotic manipulator is discussed.