Image Simulation in Remote Sensing

Remote sensing is being actively researched in the fields of environment, military and urban planning through technologies such as monitoring of natural climate phenomena on the earth, land cover classification, and object detection. Recently, satellites equipped with observation cameras of various resolutions were launched, and remote sensing images are acquired by various observation methods including cluster satellites. However, the atmospheric and environmental conditions present in the observed scene degrade the quality of images or interrupt the capture of the Earth's surface information. One method to overcome this is by generating synthetic images through image simulation. Synthetic images can be generated by using statistical or knowledge-based models or by using spectral and optic-based models to create a simulated image in place of the unobtained image at a required time. Various proposed methodologies will provide economical utility in the generation of image learning materials and time series data through image simulation. The 6 published articles cover various topics and applications central to Remote sensing image simulation. Although submission to this Special Issue is now closed, the need for further in-depth research and development related to image simulation of High-spatial and spectral resolution, sensor fusion and colorization remains.I would like to take this opportunity to express my most profound appreciation to the MDPI Book staff, the editorial team of Applied Sciences journal, especially Ms. Nimo Lang, the assistant editor of this Special Issue, talented authors, and professional reviewers

UAV-LiCAM SYSTEM DEVELOPMENT: CALIBRATION AND GEO-REFERENCING

In the last decade, applications of unmanned aerial vehicles (UAVs), as remote-sensing platforms, have extensively been investigated for fine-scale mapping, modeling and monitoring of the environment. In few recent years, integration of 3D laser scanners and cameras onboard UAVs has also received considerable attention as these two sensors provide complementary spatial/spectral information of the environment. Since lidar performs range and bearing measurements in its body-frame, precise GNSS/INS data are required to directly geo-reference the lidar measurements in an object-fixed coordinate system. However, such data comes at the price of tactical-grade inertial navigation sensors enabled with dual-frequency RTK-GNSS receivers, which also necessitates having access to a base station and proper post-processing software. Therefore, such UAV systems equipped with lidar and camera (UAV-LiCam Systems) are too expensive to be accessible to a wide range of users. Hence, new solutions must be developed to eliminate the need for costly navigation sensors. In this paper, a two-fold solution is proposed based on an in-house developed, low-cost system: 1) a multi-sensor self-calibration approach for calibrating the Li-Cam system based on planar and cylindrical multi-directional features; 2) an integrated sensor orientation method for georeferencing based on unscented particle filtering which compensates for time-variant IMU errors and eliminates the need for GNSS measurements

Technology for the Future: In-Space Technology Experiments Program, part 2

The purpose of the Office of Aeronautics and Space Technology (OAST) In-Space Technology Experiments Program In-STEP 1988 Workshop was to identify and prioritize technologies that are critical for future national space programs and require validation in the space environment, and review current NASA (In-Reach) and industry/ university (Out-Reach) experiments. A prioritized list of the critical technology needs was developed for the following eight disciplines: structures; environmental effects; power systems and thermal management; fluid management and propulsion systems; automation and robotics; sensors and information systems; in-space systems; and humans in space. This is part two of two parts and contains the critical technology presentations for the eight theme elements and a summary listing of critical space technology needs for each theme

3D Simulation of the Velodyne HDL-32E Lidar Integrated with an Autonomous Marine Vehicle

A 3D simulator is programmed for modeling the Velodyne HDL-32E LIDAR used on the WAM-V vehicle in the marine environment for obstacle detection. The model takes into account sensor integration, sensor error, and error correction. Theoretical analysis includes consideration of atmospheric refraction, time of flight error, UDP packet and timing, calibration parameter errors, depth spread error, field of view, accuracy, angular resolution, and points per second in the environment. The average distance error shows a variance of a 0.0127 m to 0.8128 m depending on the laser and the distance. Test results produce distance correction equations for each laser beam. For presented example Laser 1, the error between the corrected values and the actual distance values ranges from .02%-1.14%, which is reduced from the uncorrected error ranging from 1.32% to 3.42%. For all 32 Lasers, the real-world uncorrected distance readings have a deviation of -1.02E-05 σ to .171σ, where σ= 0.0221 m when the Red Taylor Buoy is at .518 m. The corrected distance readings deviate from 1.43E-07σ to 0.0931σ. The simulated uncorrected distance readings deviate from -0.411σ to 2.77σ, with σ= 0.0208 m. The corrected distance readings in simulation deviate from the standard by -.218σ to 2.24σ. The field of view is measured to be 41 degrees. Reflectivity and intensity profiles are presented. Physical textures are also generated based on these profiles from buoy obstacles used in the marine competition tasks. By color, the increasing order of intensity for obstacles is black, green, red, and then white. The final product consists of data used for simulation of the Velodyne HDL-32E and reporting the accuracy of simulated physical values relative to the real world testing

Research and Technology Highlights 1995

The mission of the NASA Langley Research Center is to increase the knowledge and capability of the United States in a full range of aeronautics disciplines and in selected space disciplines. This mission is accomplished by performing innovative research relevant to national needs and Agency goals, transferring technology to users in a timely manner, and providing development support to other United States Government agencies, industry, other NASA Centers, the educational community, and the local community. This report contains highlights of the major accomplishments and applications that have been made by Langley researchers and by our university and industry colleagues during the past year. The highlights illustrate both the broad range of research and technology (R&T) activities carried out by NASA Langley Research Center and the contributions of this work toward maintaining United States leadership in aeronautics and space research. An electronic version of the report is available at URL http://techreports.larc.nasa.gov/RandT95. This color version allows viewing, retrieving, and printing of the highlights, searching and browsing through the sections, and access to an on-line directory of Langley researchers

Aeronautical engineering: A continuing bibliography with indexes (supplement 289)

This bibliography lists 792 reports, articles, and other documents introduced into the NASA scientific and technical information system in Mar. 1993. Subject coverage includes: design, construction and testing of aircraft and aircraft engines; aircraft components, equipment, and systems; ground support systems; and theoretical and applied aspects of aerodynamics and general fluid dynamics

A perspective on emerging automotive safety applications, derived from lessons learned through participation in the DARPA Grand Challenges

This paper reports on various aspects of the Intelligent Vehicle Systems (IVS) team's involvement in the recent 2007 DARPA Urban Challenge, wherein our platform, the autonomous “XAV-250,'' competed as one of the 11 finalists qualifying for the event. We provide a candid discussion of the hardware and software design process that led to our team's entry, along with lessons learned at this event and derived from participation in the two previous Grand Challenges. In addition, we give an overview of our vision-, radar-, and LIDAR-based perceptual sensing suite, its fusion with a military-grade inertial navigation package, and the map-based control and planning architectures used leading up to and during the event. The underlying theme of this article is to elucidate how the development of future automotive safety systems can potentially be accelerated by tackling the technological challenges of autonomous ground vehicle robotics. Of interest, we will discuss how a production manufacturing mindset imposes a unique set of constraints upon approaching the problem and how this worked for and against us, given the very compressed timeline of the contests. © 2008 Wiley Periodicals, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/61244/1/20264_ftp.pd

Data Processing and Modeling on Volcanic and Seismic Areas

This special volume aims to collecg new ideas and contributions at the frontier between the fields of data handling, processing and modeling for volcanic and seismic systems. Technological evolution, as well as the increasing availability of new sensors and platforms, and freely available data, pose a new challenge to the scientific community in the development new tools and methods that can integrate and process different information. The recent growth in multi-sensor monitoring networks and satellites, along with the exponential increase in the spatiotemporal data, has revealed an increasingly compelling need to develop data processing, analysis and modeling tools. Data processing, analysis and modeling techniques may allow significant information to be identified and integrated into volcanic/seismological monitoring systems. The newly developed technology is expected to improve operational hazard detection, alerting, and management abilities

Definition and preliminary design of the LAWS (Laser Atmospheric Wind Sounder), volume 2, phase 2

Accurate knowledge of winds is critical to our understanding of the earth's climate and to our ability to predict climate change. Winds are a fundamental component of highly nonlinear interactions between oceans, land surfaces, and the atmosphere. Interactions at these interfaces are the focus of much climate change research. Although wind information is critical for advancing our understanding, currently most of our description of atmospheric motion is obtained indirectly - i.e., derived from observations of temperature and moisture through geostrophic relationships. Direct measurement of winds over the globe is limited to land-based rawinsonde surface stations and a few ship/aircraft reports. Cloud track winds using satellite imagery are calculated but must be used with great care. The LAWS mission objective, therefore, is to provide diurnal and global direct observations of winds - an observation that will incrementally enhance our knowledge of the earth's climate and physical processes responsible for its change. This document is Volume 2 of the LAWS Phase 2 Final Study Report and describes the definition and preliminary design of the LAWS instrument, together with details of the laser breadboard program conducted during the last 18 months of the program