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Adaptive Modeling Language and Its Derivatives

Modeling language enables automation of the entire product development cycle.Adaptive Modeling Language (AML), developed by TechnoSoft, Inc., is the underlying language of an object-oriented, multidisciplinary, knowledge-based engineering framework. TechnoSoft is a leading provider of object-oriented modeling and simulation technology used for commercial and defense applications. AML offers an advanced modeling paradigm with an open architecture, enabling the automation of the entire product development cycle, integrating product configuration, design, analysis, visualization, production planning, inspection, and cost estimation.

Posted in: Information Sciences, Briefs

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Integrating Terrain Maps Into a Reactive Navigation Strategy

Traversability of terrain is taken into account as an integral part of navigation. An improved method of processing information for autonomous navigation of a robotic vehicle across rough terrain involves the integration of terrain maps into a reactive navigation strategy. Somewhat more precisely, the method involves the incorporation, into navigation logic, of data equivalent to regional traversability maps. The terrain characteristic is mapped using a fuzzy-logic representation of the difficulty of traversing the terrain. The method is robust in that it integrates a global path-planning strategy with sensor-based regional and local navigation strategies to ensure a high probability of success in reaching a destination and avoiding obstacles along the way. The sensor-based strategies use cameras aboard the vehicle to observe the regional terrain, defined as the area of the terrain that covers the immediate vicinity near the vehicle to a specified distance a few meters away. The method at an earlier stage of development was described in “Navigating a Mobile Robot Across Terrain Using Fuzzy Logic” (), NASA Tech Briefs, Vol. 27, No. 2 (February 2003), page 5a. A recent update on the terrain classification stage of the method was reported in “Quantifying Traversability of Terrain for a Mobile Robot” (), NASA Tech Briefs, Vol. 29, No. 7 (July 2005), page 56. To recapitulate: The basic building blocks of the method are three behaviors that focus on successively smaller spatial scales and are integrated (in the sense of blended) through gains or weighting factors to generate speed and steering commands. The weighting factors are generated by fuzzy logic rules that take account of the current status of the vehicle.

Posted in: Information Sciences, Briefs, TSP

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Reducing Centroid Error Through Model-Based Noise Reduction

Corrections are made for bias and noise.A method of processing the digitized output of a charge-coupled device (CCD) image detector has been devised to enable reduction of the error in computed centroid of the image of a point source of light. The method involves model-based estimation of, and correction for, the contributions of bias and noise to the image data. The method could be used to advantage in any of a variety of applications in which there are requirements for measuring precise locations of, and/or precisely aiming optical instruments toward, point light sources.

Posted in: Information Sciences, Briefs, TSP

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NASA's Aviation Safety and Modeling Project

Capabilities for automated analysis of flight data are under development. The Aviation Safety Monitoring and Modeling (ASMM) Project of NASA’s Aviation Safety program is cultivating sources of data and developing automated computer hardware and software to facilitate efficient, comprehensive, and accurate analyses of the data collected from large, heterogeneous databases throughout the national aviation system. The ASMM addresses the need to provide means for increasing safety by enabling the identification and correcting of predisposing conditions that could lead to accidents or to incidents that pose aviation risks.

Posted in: Information Sciences, Briefs, TSP

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Developing Signal-Pattern-Recognition Programs

Software system aids development of application programs that analyze signals. An automated system to assist a General Aviation (GA) pilot in improving situational awareness of weather in flight is now undergoing development. This development is prompted by the observation that most fatal GA accidents are attributable to loss of weather awareness. Loss of weather awareness, in turn, has been attributed to the difficulty of interpreting traditional pre-flight weather briefings and the difficulty of both obtaining and interpreting traditional in-flight weather briefings. The developmental automated system not only improves weather awareness but also substantially reduces the time a pilot must spend in acquiring and maintaining weather awareness.

Posted in: Information Sciences, Briefs, TSP

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Statistical Detection of Atypical Aircraft Flights

A priori specification of search criteria is not necessary.

Posted in: Information Sciences, Briefs, TSP

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Protocols for Handling Messages Between Simulation Computers

Both time-critical and delivery-critical characteristics are accommodated. Practical Simulator Network (PSimNet) is a set of data communication protocols designed especially for use in handling messages between computers that are engaging cooperatively in real time or nearly real time training simulations. In a typical application, computers that provide individualized training at widely dispersed locations would communicate,by use of PSimNet, with a central host computer that would provide a common computational simulation environment and common data. Originally intended for use in supporting interfaces between training computers and computers that simulate the responses of spacecraft scientific payloads, PSimNet could be especially well suited for a variety of other applications — for example, group automobile driver training in a classroom. Another potential application might lie in networking of automobile diagnostic computers at repair facilities to a central computer that would compile the expertise of numerous technicians and engineers and act as an expert consulting technician.

Posted in: Information Sciences, Briefs, TSP

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