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Smith, Ben

Publications and source records attributed to Smith, Ben.

Demonstrating a New Flood Observing Strategy on the Nos Testbed

A new observing strategy for floods was demonstrated and evaluated in a testbed environment. The strategy coordinates several observing platforms, including in situ and space based, to observe a flood from multiple vantage points and to dynamically target predicted flood events with high- resolution observations. The coordinated observations were assimilated back into the model to improve forecasts and future observation selection. This demonstration shows the potential for coordinated, model-driven observing strategies and the feasibility of the NOS Testbed for demonstrating and evaluating new observing strategies.

Capra, Leigha

Software assurance of autonomous spacecraft control

The work described addresses assurance of a planning and execution software system being added to an in-orbit CubeSat to demonstrate autonomous control of that spacecraft. Our focus was on how to develop assurance of the correct operation of the added software in its operational context, our approach to which was to use an assurance case to guide and organize the information involved.

Bocchino, Robert

A Hybrid Method of Assurance Cases and Testing for Improved Confidence in Autonomous Space Systems

Autonomous systems react intelligently to their environments, making them capable of handling many possible conditions, but challenging to test. We are investigating a new test development method that aims to maximize the confidence to be achieved by combining Assurance Cases with High Throughput Testing (HTT). Assurance Cases, developed for safety-critical systems, are a rigorous argument that the system satisfies a property (e.g., the Mars rover will not tip over during a traverse). They integrate testing, analysis, and environmental and operational assumptions, from which the set of conditions that testing must cover is determined. In our method, information from the Assurance Case is used to determine the test coverage needed, and then input to HTT to generate the minimal test suites needed to provide that coverage.

Huntsberger, Terry

The ICESat-2 Laser Altimetry Mission

Satellite and aircraft observations have revealed that remarkable changes in the Earth s polar ice cover have occurred in the last decade. The impacts of these changes, which include dramatic ice loss from ice sheets and rapid declines in Arctic sea ice, could be quite large in terms of sea level rise and global climate. NASA's Ice, Cloud and Land Elevation Satellite-2 (ICESat-2), currently planned for launch in 2015, is specifically intended to quantify the amount of change in ice sheets and sea ice and provide key insights into their behavior. It will achieve these objectives through the use of precise laser measurements of surface elevation, building on the groundbreaking capabilities of its predecessor, the Ice Cloud and Land Elevation Satellite (ICESat). In particular, ICESat-2 will measure the temporal and spatial character of ice sheet elevation change to enable assessment of ice sheet mass balance and examination of the underlying mechanisms that control it. The precision of ICESat-2's elevation measurement will also allow for accurate measurements of sea ice freeboard height, from which sea ice thickness and its temporal changes can be estimated. ICESat-2 will provide important information on other components of the Earth System as well, most notably large-scale vegetation biomass estimates through the measurement of vegetation canopy height. When combined with the original ICESat observations, ICESat-2 will provide ice change measurements across more than a 15-year time span. Its significantly improved laser system will also provide observations with much greater spatial resolution, temporal resolution, and accuracy than has ever been possible before.

Abdalati, Waleed

Demonstrating Robotic Autonomy in NASA's Intelligent Systems Project

This paper will provide an overview of NASA's investments in autonomy during the past five years within the Intelligent Systems Project, with particular attention paid to investments that have resulted in mission infusion of autonomy technology, in particular, into the recent Mars Exploration Rover (MER) mission. The content of the paper will be divided into two primary topic areas: a technical overview of the component technologies developed under the program, and a programmatic overview of the history and organization of the NASA IS project itself, with a focus on describing the program elements related to autonomy and intelligent robotics. The paper will also provide an overview of the September 2004 autonomy demonstrations, including a discussion of objectives, organization, and preliminary results (to the extent they are available before the submission deadline).

Morris, Robert

Automated Reasoning CICT Program/Intelligent Systems Project ATAC-PRT Review

An overview is presented of the Automated Reasoning CICT Program/Intelligent Systems project. Automated reasoning technology will help NASA missions by increasing the amount of science achieved, ensuring safety of spacecraft and surface explorers, and by enabling more robust mission operations.

Morris, Robert

Automatic Generation of Test Oracles - From Pilot Studies to Application

There is a trend towards the increased use of automation in V&V. Automation can yield savings in time and effort. For critical systems, where thorough V&V is required, these savings can be substantial. We describe a progression from pilot studies to development and use of V&V automation. We used pilot studies to ascertain opportunities for, and suitability of, automating various analyses whose results would contribute to V&V. These studies culminated in the development of an automatic generator of automated test oracles. This was then applied and extended in the course of testing an Al planning system that is a key component of an autonomous spacecraft.

Feather, Martin S.