Gianguglielmo Calvi

A schema based model of the praying mantis

We present a schema-based agent architecture which is inspired by an ethological model of the praying mantis It includes an inner state, perceptual and motor schemas, several routines, a fovea and a motor We describe the design and implementation of the architecture and we use it for comparing two models: the former uses reactive, stimulus-response schemas; the latter involves also forward models, which are used by the schemas for generating predictions Our results show an advantage in using anticipatory components inside the schemas.

Why a Cognitive Trustier Performs Better: Simulating Trust-Based Contract Nets

We use a Contract Net protocol for comparing various strategies for trusting other agents. We introduce three classes of trustiers: a random trustier, a statistical trustier, and a cognitive trustier.

Designing modular architectures in the framework AKIRA

AKIRA is an open source framework designed for parallel, asynchronous and distributed computation, on the basis of some general architectural principles which are inspired by modular organization in biological systems. We introduce the motivation behind its design, the components of the framework and some examples of use: 1) a case study in a simple number domain, in which its capabilities such as context sensitiveness are highlighted; 2) an architecture for visual search tasks, in which a goal oriented behavior emerges from the cooperation and competition of many feature-specific modules, organized hierarchically; 3) a schema-based agent architecture, inspired by an ethological model of the praying mantis, including drives, schemas, routines and realizing visual and motor behavior in a realistic simulated environment.

Schema-Based Design and the AKIRA Schema Language: An Overview

We present a theoretical analysis of schema-based design (SBD), a methodology for designing autonomous agent architectures. We also provide an overview of the AKIRA Schema Language (AKSL), which permits to design schema-based architectures for anticipatory behavior experiments and simulations. Several simulations using AKSL are reviewed, highlighting the relations between pragmatic and epistemic aspects of behavior. Anticipation is crucial in realizing several functionalities with AKSL, such as selecting actions, orienting attention, categorizing and grounding declarative knowledge.

Fuzzy-based Schema Mechanisms in AKIRA

We compare action selection and schema mechanisms for robotic control, focusing mainly on the reactive vs. anticipatory distinction. We present AKIRA, an agent-based hybrid architecture, focusing on its capabilites to design fuzzy-based schema models. We implement in AKIRA reactive and anticipatory mechanisms, and we compare them in an experimental set-up in the visual search domain

Modulatory Influence of Motivations on a Schema-Based Architecture: A Simulative Study

We analyze the role of motivations in living organisms, and the nature of their influences on behavior with the aim to propose a design methodology for schema-based agent architectures. We propose that motivations have a modulatory influence on behavior, and in our design methodology they regulate the allocation of resources to the sensorimotor system and schemas. We describe an agent architecture incorporating this principle and we highlight its performance in a simulative study.

Dynamic computation and context effects in the hybrid architecture AKIRA

We present AKIRA, an agent-based hybrid architecture designed for cognitive modeling. We describe some of the underlying ideas motivating its development, such as the possibility of exploiting distributed representations and performing parallel, dynamic and context aware computation. We illustrate its main components and capabilities and compare it with some related cognitive architectures, such as DUAL and Copycat. We present also a sample simulation in the visual search domain, exploiting AKIRAs peculiarities for cognitive modeling.

Designing and implementing MABS in AKIRA

AbstracL Here we present AKIRA, a framework for Agent-based cognitive and social simulations. AKIRA is an open-source project, currently developed mainly at ISTC-CNR, that exploits state-of-the-art techniques and tools. It gives to the programmer a number of facilities for building Agents at different levels of complexity (e.g. reactive, deliberative, layered). Here we describe the main architectural features (i.e. Hybridism of the Agents and the Energy Model) and the theoretical assumptions that motivate it. We also present some simulations.

Contract nets for evaluating agent trustworthiness

In this paper we use a contract net protocol in order to compare various delegation strategies. We have implemented some different agents, having a set of tasks to delegate (or to perform by themselves); the tasks are performed by the agents in a dynamic environment, that can help or worse their activity. The agent rely upon different strategies in order to choose whom to delegate. We implemented three classes of trustiers: a random trustier (who randomly chooses the trustee whom delegate the task to); a statistical trustier (who builds the trustworthiness of other agents only on the basis of their previous performances); a cognitive trustier (who builds a sophisticated and cognitively motivated trust model of the trustee, taking into account its specific features, its ability and motivational disposition, and the impact of the environment on its performance). Our experiments show the advantage of using cognitive representations.

Integrating a MAS and a Pandemonium: the open-source framework AKIRA

The open-source framework AKIRA integrates Multiagent and Pandemonium elements. We describe the main components of the framework, showing that the hybrid nature of the Agents, having symbolic and connectionist features, permits to model many functionalities such as implicit communication and coordination.