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Simulating human behavior for national security human interactions

Bernard, Michael L.; Glickman, Matthew R.; Hart, Derek H.; Xavier, Patrick G.; Verzi, Stephen J.; Wolfenbarger, Paul W.

This 3-year research and development effort focused on what we believe is a significant technical gap in existing modeling and simulation capabilities: the representation of plausible human cognition and behaviors within a dynamic, simulated environment. Specifically, the intent of the ''Simulating Human Behavior for National Security Human Interactions'' project was to demonstrate initial simulated human modeling capability that realistically represents intra- and inter-group interaction behaviors between simulated humans and human-controlled avatars as they respond to their environment. Significant process was made towards simulating human behaviors through the development of a framework that produces realistic characteristics and movement. The simulated humans were created from models designed to be psychologically plausible by being based on robust psychological research and theory. Progress was also made towards enhancing Sandia National Laboratories existing cognitive models to support culturally plausible behaviors that are important in representing group interactions. These models were implemented in the modular, interoperable, and commercially supported Umbra{reg_sign} simulation framework.

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A robotic framework for semantic concept learning

Xavier, Patrick G.

This report describes work carried out under a Sandia National Laboratories Excellence in Engineering Fellowship in the Department of Electrical and Computer Engineering at the University of Illinois at Urbana-Champaign. Our research group (at UIUC) is developing a intelligent robot, and attempting to teach it language. While there are many aspects of this research, for the purposes of this report the most important are the following ideas. Language is primarily based on semantics, not syntax. To truly learn meaning, the language engine must be part of an embodied intelligent system, one capable of using associative learning to form concepts from the perception of experiences in the world, and further capable of manipulating those concepts symbolically. In the work described here, we explore the use of hidden Markov models (HMMs) in this capacity. HMMs are capable of automatically learning and extracting the underlying structure of continuous-valued inputs and representing that structure in the states of the model. These states can then be treated as symbolic representations of the inputs. We describe a composite model consisting of a cascade of HMMs that can be embedded in a small mobile robot and used to learn correlations among sensory inputs to create symbolic concepts. These symbols can then be manipulated linguistically and used for decision making. This is the project final report for the University Collaboration LDRD project, 'A Robotic Framework for Semantic Concept Learning'.

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Final report for the endowment of simulator agents with human-like episodic memory LDRD

Forsythe, James C.; Forsythe, James C.; Speed, Ann S.; Lippitt, Carl E.; Schaller, Mark J.; Xavier, Patrick G.; Thomas, Edward V.; Schoenwald, David A.

This report documents work undertaken to endow the cognitive framework currently under development at Sandia National Laboratories with a human-like memory for specific life episodes. Capabilities have been demonstrated within the context of three separate problem areas. The first year of the project developed a capability whereby simulated robots were able to utilize a record of shared experience to perform surveillance of a building to detect a source of smoke. The second year focused on simulations of social interactions providing a queriable record of interactions such that a time series of events could be constructed and reconstructed. The third year addressed tools to promote desktop productivity, creating a capability to query episodic logs in real time allowing the model of a user to build on itself based on observations of the user's behavior.

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Engineering a transformation of human-machine interaction to an augmented cognitive relationship

Forsythe, James C.; Forsythe, James C.; Bernard, Michael L.; Xavier, Patrick G.; Abbott, Robert G.; Speed, Ann S.; Brannon, Nathan B.

This project is being conducted by Sandia National Laboratories in support of the DARPA Augmented Cognition program. Work commenced in April of 2002. The objective for the DARPA program is to 'extend, by an order of magnitude or more, the information management capacity of the human-computer warfighter.' Initially, emphasis has been placed on detection of an operator's cognitive state so that systems may adapt accordingly (e.g., adjust information throughput to the operator in response to workload). Work conducted by Sandia focuses on development of technologies to infer an operator's ongoing cognitive processes, with specific emphasis on detecting discrepancies between machine state and an operator's ongoing interpretation of events.

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Content-Based Search on a Database of Geometric Models: Identifying Objects of Similar Shape

Xavier, Patrick G.; Lafarge, Robert A.; Ray, Lawrence P.

The Geometric Search Engine is a software system for storing and searching a database of geometric models. The database maybe searched for modeled objects similar in shape to a target model supplied by the user. The database models are generally from CAD models while the target model may be either a CAD model or a model generated from range data collected from a physical object. This document describes key generation, database layout, and search of the database.

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The Umbra Simulation Framework

Gottlieb, Eric J.; Harrigan, Raymond W.; McDonald, Michael J.; Oppel, Frederick J.; Xavier, Patrick G.; McDonald, Michael J.

Umbra is a new Sandia-developed modeling and simulation framework. The Umbra framework allows users to quickly build models and simulations for intelligent system development, analysis, experimentation, and control and supports tradeoff analyses of complex robotic systems, device, and component concepts. Umbra links together heterogeneous collections of modeling tools. The models in Umbra include 3D geometry and physics models of robots, devices and their environments. Model components can be built with varying levels of fidelity and readily switched to allow models built with low fidelity for conceptual analysis to be gradually converted to high fidelity models for later phase detailed analysis. Within control environments, the models can be readily replaced with actual control elements. This paper describes Umbra at a functional level and describes issues that Sandia uses Umbra to address.

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Results 26–32 of 32
Results 26–32 of 32