This document provides an overview of an Eastern West Virginia LiDAR acquisition project. Key details include the project was 100% complete, products are being delivered as completed, and specifications were designed to meet FEMA and USGS requirements. Contact information is provided for several project managers from Dewberry and USGS.
This document discusses Light Detection and Ranging (LiDAR) technology. It begins with an introduction to LiDAR, describing how it uses laser pulses to measure distance. It then provides details on the components and functioning of LiDAR systems, including lasers, scanners, detectors, and positioning systems. The document concludes by outlining various applications of LiDAR in fields such as geology, meteorology, archaeology, biology, and more.
LIDAR is a remote sensing technology that uses lasers to measure properties of scattered light. It measures the time delay between the transmitted and reflected signals to determine the distance to an object. LIDAR consists of a laser transmitter, receiver, and detector. It uses much shorter wavelengths than RADAR, allowing for higher resolution. Common applications of LIDAR include topographic mapping, atmospheric research, robotics, archaeology, geology, and astronomy.
LIDAR is an acronym for light detection and ranging. It is an optical remote sensing technology used to examine the surface of the earth, often using pulses from a laser.
LIDAR is a remote sensing method that uses light in the form of a pulsed laser to measure ranges (variable distances) to the Earth. It can be used to generate precise, three-dimensional information about the structure of objects and terrain. LIDAR involves the measurement of distance to a target by illuminating that target with laser light and measuring the reflected pulses with a sensor. Differences in laser return times and wavelengths can then be used to make digital 3D representations of the target. LIDAR originated in the 1960s and has various applications including terrain mapping, atmospheric studies, robotics, autonomous vehicles, archaeology, geology and forestry.
LIDAR uses pulsed laser light to measure distance by illuminating targets and analyzing reflections. It can be used to create high-resolution 3D maps of physical features and is useful for applications in fields like agriculture, biology, engineering and law enforcement. LIDAR offers advantages over other mapping methods like higher accuracy, faster data collection and greater data density.
Lidar is an acronym for light detection and ranging. It is an optical remote sensing technology that can measure the distance to, or other properties of a target by illuminating the target with light, often using pulses from a laser.
Lidar (also written LIDAR, LiDAR or LADAR) is a remote sensing technology that measures distance by illuminating a target with a laser and analyzing the reflected light. Although thought by some to be an acronym of Light Detection And Ranging,[1] the term lidar was actually created as a portmanteau of "light" and "radar".[2][3] Lidar is popularly used as a technology to make high-resolution maps, with applications in geodesy, geomatics, archaeology, geography, geology, geomorphology, seismology, forestry, remote sensing, atmospheric physics,[4] airborne laser swath mapping (ALSM), laser altimetry, and contour mapping.
Itroduction to lidar ground, ballon&air born lidaranuarag1992
Lidar is a remote sensing technology that uses laser light to measure distances by illuminating a target and analyzing the reflected light. It can be used to image objects using ultraviolet, visible, or infrared light. Lidar systems include a laser, telescope, photomultiplier tube, and filters. There are different types of lidar systems including airborne lidar mounted on aircraft, ground-based stationary lidar, and balloon-borne lidar used to study the atmosphere. Applications of lidar include atmospheric research, oil and gas exploration, forestry management, and cellular network planning.
This document discusses Light Detection and Ranging (LiDAR) technology. It begins with an introduction to LiDAR, describing how it uses laser pulses to measure distance. It then provides details on the components and functioning of LiDAR systems, including lasers, scanners, detectors, and positioning systems. The document concludes by outlining various applications of LiDAR in fields such as geology, meteorology, archaeology, biology, and more.
LIDAR is a remote sensing technology that uses lasers to measure properties of scattered light. It measures the time delay between the transmitted and reflected signals to determine the distance to an object. LIDAR consists of a laser transmitter, receiver, and detector. It uses much shorter wavelengths than RADAR, allowing for higher resolution. Common applications of LIDAR include topographic mapping, atmospheric research, robotics, archaeology, geology, and astronomy.
LIDAR is an acronym for light detection and ranging. It is an optical remote sensing technology used to examine the surface of the earth, often using pulses from a laser.
LIDAR is a remote sensing method that uses light in the form of a pulsed laser to measure ranges (variable distances) to the Earth. It can be used to generate precise, three-dimensional information about the structure of objects and terrain. LIDAR involves the measurement of distance to a target by illuminating that target with laser light and measuring the reflected pulses with a sensor. Differences in laser return times and wavelengths can then be used to make digital 3D representations of the target. LIDAR originated in the 1960s and has various applications including terrain mapping, atmospheric studies, robotics, autonomous vehicles, archaeology, geology and forestry.
LIDAR uses pulsed laser light to measure distance by illuminating targets and analyzing reflections. It can be used to create high-resolution 3D maps of physical features and is useful for applications in fields like agriculture, biology, engineering and law enforcement. LIDAR offers advantages over other mapping methods like higher accuracy, faster data collection and greater data density.
Lidar is an acronym for light detection and ranging. It is an optical remote sensing technology that can measure the distance to, or other properties of a target by illuminating the target with light, often using pulses from a laser.
Lidar (also written LIDAR, LiDAR or LADAR) is a remote sensing technology that measures distance by illuminating a target with a laser and analyzing the reflected light. Although thought by some to be an acronym of Light Detection And Ranging,[1] the term lidar was actually created as a portmanteau of "light" and "radar".[2][3] Lidar is popularly used as a technology to make high-resolution maps, with applications in geodesy, geomatics, archaeology, geography, geology, geomorphology, seismology, forestry, remote sensing, atmospheric physics,[4] airborne laser swath mapping (ALSM), laser altimetry, and contour mapping.
Itroduction to lidar ground, ballon&air born lidaranuarag1992
Lidar is a remote sensing technology that uses laser light to measure distances by illuminating a target and analyzing the reflected light. It can be used to image objects using ultraviolet, visible, or infrared light. Lidar systems include a laser, telescope, photomultiplier tube, and filters. There are different types of lidar systems including airborne lidar mounted on aircraft, ground-based stationary lidar, and balloon-borne lidar used to study the atmosphere. Applications of lidar include atmospheric research, oil and gas exploration, forestry management, and cellular network planning.
LIDAR is an acronym for LIght Detection And Ranging. It is an optical remote sensing technology that can measure the distance to or other properties of a target by illuminating the target with light pulse to form an image.
LIDAR is a remote sensing technology that uses laser pulses to measure distances to surfaces. It can generate highly accurate 3D models of terrain and other physical features. LIDAR data consists of a dense cloud of elevation points that can be used to create digital elevation models, contour maps, and other products. Advances in GPS, laser, and inertial measurement technologies have made airborne LIDAR capable of collecting millions of elevation points per second with sub-meter horizontal and 15-30 cm vertical accuracy. LIDAR data has many applications for mapping forests, urban areas, watersheds and other landscapes.
LIDAR uses laser light to measure distance by illuminating a target and analyzing the reflected light. It can be used to generate highly accurate 3D models of terrain, infrastructure, and other physical features. LIDAR systems consist of a laser, scanner, photodetector, and navigation components. LIDAR has various applications in fields like geography, archaeology, environment, and autonomous vehicles due to its ability to rapidly capture precise spatial data regardless of lighting conditions.
This document provides an introduction to LIDAR (Light Detection and Ranging) technology. It describes LIDAR as a remote sensing method that uses lasers to measure properties of scattered light to find range and other information of objects, similar to radar but using optical pulses. The document outlines the basic components, working principles, history and applications of LIDAR systems. It explains how LIDAR can be used for tasks like mapping terrain, monitoring forests and crops, surveying archaeological sites, and studying the atmosphere.
Light Detection And Ranging (useless in slideshare, must be downloaded to pow...Nina Tvenge
LIDAR is an optical remote sensing technology that uses lasers to measure distances. It works by measuring the time delay between transmitting a laser pulse and receiving the reflected signal, which provides highly detailed 3D mapping. LIDAR has a wide variety of uses including archaeology, meteorology, geology, biology, military applications, vehicles, imaging, and 3D mapping.
The document discusses the use of LiDAR (light detection and ranging) technology for various applications such as flood plain mapping, transportation infrastructure, forestry management, and more. It provides details on LiDAR accuracy standards, processing methods, and deliverable data formats. The presentation aims to help audiences understand how LiDAR data can aid in decision-making processes.
This document provides an overview of Mobile Laser Scanning technology using the Dynascan 3D mobile mapping system. It discusses how mobile scanning is an advancement on traditional surveying methods. The agenda includes introductions, presentations on the technology and Measurement Devices Limited, a live demo, and Q&A. Measurement Devices Limited is a leading designer and manufacturer of laser measurement technology for over 30 years. The Dynascan system is a fully integrated high-speed laser scanner, GPS, and inertial navigation system that is rugged, portable, and suitable for a wide range of land and marine applications. The document highlights the Dynascan system's capabilities and provides examples of its use in infrastructure, coastal, and construction projects.
LiDAR uses laser light to rapidly create high-resolution 3D models of objects and terrain. It has largely replaced photogrammetry for topographic mapping due to its ability to collect data day or night and its direct measurement of ground surfaces. While public LiDAR datasets are useful for planning, private firms can benefit more from terrestrial and aerial LiDAR for detailed civil engineering and surveying projects. LiDAR allows rapid mapping of complex sites and piping networks to support master planning, grading, utilities, and other design work.
LIDAR is a remote sensing technology that uses laser light to measure distances to the Earth. It can generate highly accurate digital elevation models and other 3D data about physical features and land cover. LIDAR works by measuring the time it takes for a laser to travel from a sensor to the ground and back. This allows it to determine the precise latitude, longitude, and elevation for each point. LIDAR data comes in the form of dense point clouds containing hundreds of thousands or millions of points per square kilometer. LIDAR has many applications, including mapping terrain and creating contours, modeling forests and individual trees, and modeling urban infrastructure for planning and emergency response. Accuracies of LIDAR elevation data are typically
LiDAR is a remote sensing method that uses light in the form of a pulsed laser to measure variable distances to the Earth. It can be used to create high resolution digital elevation models and terrain models. The document discusses the benefits of high resolution LiDAR data, including more accurate terrain data, multiple applications, and a return on investment of $4-5 for every $1 spent on LiDAR collection. It also provides examples of government agencies that regularly collect and update LiDAR data.
Light detection and ranging (LiDAR) is a remote sensing method that uses pulsed laser light to image objects and measure distances. It can be used for applications such as autonomous vehicles, forest planning and management, river surveying, and oil and gas exploration. The document discusses the history, principles, components, types, concepts and applications of LiDAR technology.
2012 Workshop, Introduction to LiDAR Workshop, Bruce Adey and Mark Stucky (Me...GIS in the Rockies
The document provides an introduction to LiDAR technology and applications presented by GIS in the Rockies. It includes bios of the two presenters, an overview of the company Merrick & Company, and an agenda for the workshop covering LiDAR technology review, applications, data processing workflow, project planning, and Q&A. The workshop aims to educate attendees on airborne LiDAR data acquisition projects through a practical review of technical requirements and benefits of the technology.
LiDAR and its application in civil engineeringchippi babu
The document discusses the use of LIDAR (Light Detection and Ranging) technology in civil engineering applications. It describes LIDAR's components, principles of operation, and its advantages over other remote sensing methods. Key applications mentioned include topographic and hydrographic surveying to generate digital terrain models, bridge clearance measurement, and sewer inspection. The document concludes that LIDAR offers highly accurate data collection with minimal human involvement.
LiDAR Data Processing and ClassificationMichal Bularz
This document discusses techniques for interpreting point cloud and image data through automated algorithms that translate human visual interpretations. It describes popular approaches for processing LiDAR point clouds, including height-based segmentation to classify features above the ground and shape-fitting algorithms. It also discusses using spectral information through intensity values or image fusion. Finally, it examines developing "computer vision" tools that can segment data based on visual cues humans use like color, texture, morphology, context and defined shapes. The goal is to replicate human visual interpretation abilities through algorithms.
The document discusses LiDAR technology and its applications in forestry. It begins by explaining what LiDAR is and the different platforms it can be used on, including satellites, aircraft, and ground-based systems. It then discusses several forestry applications of LiDAR such as measuring tree height, crown width, biomass, and basal area. Two case studies are presented, one on estimating carbon stock in an urban forest using LiDAR data, and another on estimating forest canopy fuels. The document concludes that LiDAR provides highly accurate, high-resolution data that allows forest characteristics to be acquired quickly and is useful for applications like biomass estimation and modeling fire behavior.
This document summarizes Brian McLaughlin's final project comparing LiDAR and field survey data. The project tests the accuracy of airborne LiDAR data in a heavily wooded area of Dallas against survey-grade GPS data. Overall, the LiDAR data was found to be within acceptable tolerances for elevation. While not as accurate as total station or GPS, LiDAR can supplement field survey techniques and reduce costs, especially with the rise of UAV-based LiDAR sensors. The literature review found most applications are for terrestrial LiDAR, but airborne uses like airport mapping produce sub-5cm horizontal and vertical accuracy. Advances in sensor technology allow denser point clouds from higher altitudes.
Lidar is an optical remote sensing technology that uses light (often from a pulsed laser) to measure distance. It works by illuminating a target with a laser and analyzing the reflected light. Common components of a lidar system include a laser, scanner/optics, photodetector, and receiver electronics. Lidar has advantages over radar like faster lock-on time and narrower beam spread. Applications include agriculture, mapping, oil/gas exploration, engineering, autonomous vehicles, and atmospheric sensing from aircraft or satellites. Recent advances include lidar speed guns, Google's driverless car which uses lidar for navigation, and autonomous cruise control systems using lidar.
This document provides an overview of different types of LiDAR acquisition methods. Aerial LiDAR is used to capture large areas and generates 2.5D data by scanning from aircraft. Terrestrial LiDAR captures smaller areas in full 3D using static or mobile ground-based units. Bathymetric LiDAR maps shallow underwater areas using dual lasers. Atmospheric LiDAR surveys air properties by transmitting laser pulses and analyzing backscatter. Common to all is using a laser transmitter and detector to measure discrete points or full waveforms, with variations depending on the objective and environment.
This document discusses factors to consider when planning and conducting a LiDAR data acquisition project to ensure accurate results. It covers planning the flight path and sensor settings, conducting pre-flight control surveys, calibration procedures during data collection flights, and performing initial approximate processing checks of the raw GPS, IMU, and laser point data to validate data quality. The goal is to identify and address any issues early to help meet the desired level of positional and elevation accuracy.
LiDAR uses laser pulses to measure distances to surfaces and create 3D point clouds. It provides accurate elevation data day or night. Sources of error include scan angle, strip adjustment, ground point selection, interpolation, and visualization. Acquisition factors like flight parameters and weather affect data quality. Processing involves correcting systematic errors between flight lines and filtering points. Derivative products include DEMs, DTMs, and intensity images. Validation is needed due to inherent errors introduced during data collection and processing.
LIDAR uses laser light to measure distance by illuminating a target and analyzing the reflected light. It can be used to generate highly accurate 3D models of terrain, infrastructure, and other physical features. LIDAR systems consist of a laser, scanner, photodetector, and navigation components. LIDAR has various applications in fields like geography, archaeology, environment, and autonomous vehicles due to its ability to rapidly capture precise spatial data regardless of lighting conditions.
LIDAR is an acronym for LIght Detection And Ranging. It is an optical remote sensing technology that can measure the distance to or other properties of a target by illuminating the target with light pulse to form an image.
LIDAR is a remote sensing technology that uses laser pulses to measure distances to surfaces. It can generate highly accurate 3D models of terrain and other physical features. LIDAR data consists of a dense cloud of elevation points that can be used to create digital elevation models, contour maps, and other products. Advances in GPS, laser, and inertial measurement technologies have made airborne LIDAR capable of collecting millions of elevation points per second with sub-meter horizontal and 15-30 cm vertical accuracy. LIDAR data has many applications for mapping forests, urban areas, watersheds and other landscapes.
LIDAR uses laser light to measure distance by illuminating a target and analyzing the reflected light. It can be used to generate highly accurate 3D models of terrain, infrastructure, and other physical features. LIDAR systems consist of a laser, scanner, photodetector, and navigation components. LIDAR has various applications in fields like geography, archaeology, environment, and autonomous vehicles due to its ability to rapidly capture precise spatial data regardless of lighting conditions.
This document provides an introduction to LIDAR (Light Detection and Ranging) technology. It describes LIDAR as a remote sensing method that uses lasers to measure properties of scattered light to find range and other information of objects, similar to radar but using optical pulses. The document outlines the basic components, working principles, history and applications of LIDAR systems. It explains how LIDAR can be used for tasks like mapping terrain, monitoring forests and crops, surveying archaeological sites, and studying the atmosphere.
Light Detection And Ranging (useless in slideshare, must be downloaded to pow...Nina Tvenge
LIDAR is an optical remote sensing technology that uses lasers to measure distances. It works by measuring the time delay between transmitting a laser pulse and receiving the reflected signal, which provides highly detailed 3D mapping. LIDAR has a wide variety of uses including archaeology, meteorology, geology, biology, military applications, vehicles, imaging, and 3D mapping.
The document discusses the use of LiDAR (light detection and ranging) technology for various applications such as flood plain mapping, transportation infrastructure, forestry management, and more. It provides details on LiDAR accuracy standards, processing methods, and deliverable data formats. The presentation aims to help audiences understand how LiDAR data can aid in decision-making processes.
This document provides an overview of Mobile Laser Scanning technology using the Dynascan 3D mobile mapping system. It discusses how mobile scanning is an advancement on traditional surveying methods. The agenda includes introductions, presentations on the technology and Measurement Devices Limited, a live demo, and Q&A. Measurement Devices Limited is a leading designer and manufacturer of laser measurement technology for over 30 years. The Dynascan system is a fully integrated high-speed laser scanner, GPS, and inertial navigation system that is rugged, portable, and suitable for a wide range of land and marine applications. The document highlights the Dynascan system's capabilities and provides examples of its use in infrastructure, coastal, and construction projects.
LiDAR uses laser light to rapidly create high-resolution 3D models of objects and terrain. It has largely replaced photogrammetry for topographic mapping due to its ability to collect data day or night and its direct measurement of ground surfaces. While public LiDAR datasets are useful for planning, private firms can benefit more from terrestrial and aerial LiDAR for detailed civil engineering and surveying projects. LiDAR allows rapid mapping of complex sites and piping networks to support master planning, grading, utilities, and other design work.
LIDAR is a remote sensing technology that uses laser light to measure distances to the Earth. It can generate highly accurate digital elevation models and other 3D data about physical features and land cover. LIDAR works by measuring the time it takes for a laser to travel from a sensor to the ground and back. This allows it to determine the precise latitude, longitude, and elevation for each point. LIDAR data comes in the form of dense point clouds containing hundreds of thousands or millions of points per square kilometer. LIDAR has many applications, including mapping terrain and creating contours, modeling forests and individual trees, and modeling urban infrastructure for planning and emergency response. Accuracies of LIDAR elevation data are typically
LiDAR is a remote sensing method that uses light in the form of a pulsed laser to measure variable distances to the Earth. It can be used to create high resolution digital elevation models and terrain models. The document discusses the benefits of high resolution LiDAR data, including more accurate terrain data, multiple applications, and a return on investment of $4-5 for every $1 spent on LiDAR collection. It also provides examples of government agencies that regularly collect and update LiDAR data.
Light detection and ranging (LiDAR) is a remote sensing method that uses pulsed laser light to image objects and measure distances. It can be used for applications such as autonomous vehicles, forest planning and management, river surveying, and oil and gas exploration. The document discusses the history, principles, components, types, concepts and applications of LiDAR technology.
2012 Workshop, Introduction to LiDAR Workshop, Bruce Adey and Mark Stucky (Me...GIS in the Rockies
The document provides an introduction to LiDAR technology and applications presented by GIS in the Rockies. It includes bios of the two presenters, an overview of the company Merrick & Company, and an agenda for the workshop covering LiDAR technology review, applications, data processing workflow, project planning, and Q&A. The workshop aims to educate attendees on airborne LiDAR data acquisition projects through a practical review of technical requirements and benefits of the technology.
LiDAR and its application in civil engineeringchippi babu
The document discusses the use of LIDAR (Light Detection and Ranging) technology in civil engineering applications. It describes LIDAR's components, principles of operation, and its advantages over other remote sensing methods. Key applications mentioned include topographic and hydrographic surveying to generate digital terrain models, bridge clearance measurement, and sewer inspection. The document concludes that LIDAR offers highly accurate data collection with minimal human involvement.
LiDAR Data Processing and ClassificationMichal Bularz
This document discusses techniques for interpreting point cloud and image data through automated algorithms that translate human visual interpretations. It describes popular approaches for processing LiDAR point clouds, including height-based segmentation to classify features above the ground and shape-fitting algorithms. It also discusses using spectral information through intensity values or image fusion. Finally, it examines developing "computer vision" tools that can segment data based on visual cues humans use like color, texture, morphology, context and defined shapes. The goal is to replicate human visual interpretation abilities through algorithms.
The document discusses LiDAR technology and its applications in forestry. It begins by explaining what LiDAR is and the different platforms it can be used on, including satellites, aircraft, and ground-based systems. It then discusses several forestry applications of LiDAR such as measuring tree height, crown width, biomass, and basal area. Two case studies are presented, one on estimating carbon stock in an urban forest using LiDAR data, and another on estimating forest canopy fuels. The document concludes that LiDAR provides highly accurate, high-resolution data that allows forest characteristics to be acquired quickly and is useful for applications like biomass estimation and modeling fire behavior.
This document summarizes Brian McLaughlin's final project comparing LiDAR and field survey data. The project tests the accuracy of airborne LiDAR data in a heavily wooded area of Dallas against survey-grade GPS data. Overall, the LiDAR data was found to be within acceptable tolerances for elevation. While not as accurate as total station or GPS, LiDAR can supplement field survey techniques and reduce costs, especially with the rise of UAV-based LiDAR sensors. The literature review found most applications are for terrestrial LiDAR, but airborne uses like airport mapping produce sub-5cm horizontal and vertical accuracy. Advances in sensor technology allow denser point clouds from higher altitudes.
Lidar is an optical remote sensing technology that uses light (often from a pulsed laser) to measure distance. It works by illuminating a target with a laser and analyzing the reflected light. Common components of a lidar system include a laser, scanner/optics, photodetector, and receiver electronics. Lidar has advantages over radar like faster lock-on time and narrower beam spread. Applications include agriculture, mapping, oil/gas exploration, engineering, autonomous vehicles, and atmospheric sensing from aircraft or satellites. Recent advances include lidar speed guns, Google's driverless car which uses lidar for navigation, and autonomous cruise control systems using lidar.
This document provides an overview of different types of LiDAR acquisition methods. Aerial LiDAR is used to capture large areas and generates 2.5D data by scanning from aircraft. Terrestrial LiDAR captures smaller areas in full 3D using static or mobile ground-based units. Bathymetric LiDAR maps shallow underwater areas using dual lasers. Atmospheric LiDAR surveys air properties by transmitting laser pulses and analyzing backscatter. Common to all is using a laser transmitter and detector to measure discrete points or full waveforms, with variations depending on the objective and environment.
This document discusses factors to consider when planning and conducting a LiDAR data acquisition project to ensure accurate results. It covers planning the flight path and sensor settings, conducting pre-flight control surveys, calibration procedures during data collection flights, and performing initial approximate processing checks of the raw GPS, IMU, and laser point data to validate data quality. The goal is to identify and address any issues early to help meet the desired level of positional and elevation accuracy.
LiDAR uses laser pulses to measure distances to surfaces and create 3D point clouds. It provides accurate elevation data day or night. Sources of error include scan angle, strip adjustment, ground point selection, interpolation, and visualization. Acquisition factors like flight parameters and weather affect data quality. Processing involves correcting systematic errors between flight lines and filtering points. Derivative products include DEMs, DTMs, and intensity images. Validation is needed due to inherent errors introduced during data collection and processing.
LIDAR uses laser light to measure distance by illuminating a target and analyzing the reflected light. It can be used to generate highly accurate 3D models of terrain, infrastructure, and other physical features. LIDAR systems consist of a laser, scanner, photodetector, and navigation components. LIDAR has various applications in fields like geography, archaeology, environment, and autonomous vehicles due to its ability to rapidly capture precise spatial data regardless of lighting conditions.
Airborne Laser Scanning Remote Sensing with LiDAR.pptssuser6358fd
1. Airborne laser scanning (ALS), also known as LiDAR, is an active remote sensing technology that uses laser light to measure distances.
2. There are two main types of ALS systems - waveform systems that record the full energy pulse and discrete-return systems that sample returns if the laser reflection exceeds an energy threshold.
3. ALS has various applications including generating high-resolution digital elevation models, mapping forest structure, and measuring changes in terrain and vegetation over time.
LiDAR is an optical remote sensing technology that uses laser light to densely sample the surface of the Earth. It can collect data quickly and accurately to generate precise, 3D information about physical features and terrain. LiDAR systems determine the distance between an object and the sensor by measuring the time delay between transmission and detection of a laser pulse. Key components include a laser, receiver, timing electronics, and computer. Applications of LiDAR include generating high-resolution maps, modeling pollution distribution, monitoring agriculture and forestry, and facilitating autonomous vehicles.
LIDAR uses laser pulses to map terrain by measuring distance to a target. Airborne LIDAR systems consist of laser pulse generators, optics and scanners to direct pulses toward the ground, photodetectors and receivers to measure return times, and navigation systems to record pulse locations. Return times are used to calculate distances and generate high-resolution digital elevation models, terrain models, and orthophotos.
LIDAR uses laser pulses to map terrain by measuring distance to objects. Airborne LIDAR systems consist of laser pulse generators, scanners and optics, photodetectors, navigation systems, and processing software. Laser pulses are emitted and their reflection times are used to calculate distances to create high resolution digital elevation models and orthophotos.
LIDAR uses laser pulses to map terrain by measuring distance to targets. Airborne LIDAR systems consist of laser pulse generators, typically 1064nm or 532nm lasers, optics to direct pulses to the ground in swaths, and receivers to detect reflected pulses. Precise timing of reflections allows distance to be calculated, while onboard GPS and navigation track the aircraft position. Computer software processes massive point clouds into high resolution digital elevation models, terrain maps, and other geospatial data products.
LIDAR uses laser light to measure distances and create 3D representations of environments. It works by emitting laser pulses and measuring their reflection off objects. There are several types including ground-based, airborne, and spaceborne LIDAR. It has many applications such as mapping terrain, monitoring infrastructure, surveying rivers, autonomous vehicles, and more. LIDAR provides highly accurate 3D data that is useful for various industries like agriculture, geology, archaeology, and more.
LIDAR- Modern techniques in Surveying.pptxsurekha1287
LIDAR is a remote sensing technology that uses laser light to densely sample the surface of the Earth. It stands for Light Detection and Ranging and is similar to RADAR but uses optical pulses instead of radio waves. LIDAR systems precisely measure distance by timing how long it takes a laser pulse to return after reflecting off an object. This allows highly accurate 3D mapping of the surface. LIDAR has many applications in fields like agriculture, archaeology, geology, hydrology and more. It provides advantages over traditional surveying through higher accuracy, data density, and independence from weather or lighting conditions. However, LIDAR cannot operate through clouds like RADAR and is limited to fair weather use.
This document provides an overview of light detection and ranging (LiDAR) technology. It discusses the need for LiDAR to enable remote sensing, automation, and object identification. The basic working principle of LiDAR is described, which involves using laser pulses to measure the time it takes for light to reflect off objects and return. Key design considerations for LiDAR systems are highlighted, such as laser wavelength and power, pulse repetition rate, and challenges like background noise. Applications of LiDAR and related technologies are presented along with examples of further research opportunities.
Synthetic aperture radar (SAR) uses the motion of the radar platform to synthesize a large antenna aperture, providing very high cross-range resolution. It collects returns sequentially and processes them as if collected simultaneously. Inverse SAR uses target motion instead of platform motion, allowing imaging of moving objects like ships. Both techniques overcome limitations of conventional radar to generate high-resolution radar images of terrain and targets.
Lidar technology allows for highly accurate elevation data collection through airborne laser scanning. It has advantages over traditional surveying and photogrammetry by being able to collect data day or night without issues from shadows. While lidar provides elevation points, it does not directly capture breaklines or planimetric features without additional processing. Accuracy of lidar data ranges from 6 to 30 centimeters vertically and 10 to 46 centimeters horizontally, depending on factors like flying height and GPS configuration. Lidar has many applications for projects requiring high-accuracy terrain modeling like transportation, forestry, and flood mapping.
Rahul Bhagore presented on LIDAR (Light Detection and Ranging) technology. LIDAR uses laser pulses to measure distance by illuminating a target and analyzing the reflected light. It has applications in fields like agriculture, conservation, and law enforcement. LIDAR systems can be airborne, terrestrial, mobile, or static. Key components include lasers, scanners, detectors, and navigation systems. LIDAR provides highly accurate 3D data at large scales and through foliage, with advantages over other remote sensing methods.
Introduction to li dar technology advanced remote sensingBrightTimeStudio
This document provides an overview of LiDAR technology presented by Mr. Ashenafi B. It describes the components of a LiDAR system including lasers, scanners, GPS, and high-precision clocks. The principles of LiDAR are explained such as how it measures distance using time of flight and records location and orientation data. Different LiDAR types and platforms like airborne, terrestrial, and satellite are covered. Applications including DEM generation, forest inventory, and landslide analysis are listed. Advantages of LiDAR are high accuracy and weather independence while disadvantages include high costs and lack of foliage penetration.
LiDER (Light Detection and Ranging) is an active remote sensing method that uses lasers to measure variable distances to objects on Earth. It can penetrate low density materials like trees. A LiDER system sends out pulses of light and measures the return time to create 3D representations of surfaces. Key components include laser scanners, high precision clocks, GPS, and IMUs. It has many applications like mapping terrain, vegetation analysis, and disaster assessment.
This document provides an introduction to LiDAR technology for machine perception. It begins with an overview of LiDAR fundamentals and principles, explaining that LiDAR works similarly to radar but uses laser light instead of radio waves. It then discusses different types of LiDAR sensors and scanning methods, as well as strategies for processing LiDAR point cloud data. The document concludes with examples of common LiDAR representations and neural network architectures used for tasks like object detection from LiDAR point clouds.
RADAR (Radio Detection and Ranging) uses radio pulses transmitted in the direction of a target and observes the reflection to detect and study distant targets. It measures a target's range, angles, size, speed, and features. The major radar components are an antenna, transmitter, receiver and display. Radar operates at different frequency bands and is used for applications like air traffic control, weather monitoring, and navigation.
This content presents for basic of Synthetic Aperture Radar (SAR) including its geometry, how the image is created, essential parameters, interpretation, SAR sensor specification, and advantages and disadvantages.
The Flood Risk Review meeting was held on April 12, 2016 in Morgantown, WV to discuss updates to the Flood Insurance Study and Flood Insurance Rate Maps for parts of the Upper Monongahela Watershed. The meeting agenda included an overview of the Risk MAP program, the project extents and methodology, where to access flood risk products, and a work session to review maps and provide feedback. Attendees included representatives from federal, state, and local partner organizations.
Eastern Panhandle GIS Users Group Meeting held on 14 September 2016 in Martinsburg, WV. Presenters Kathryn Wesson & Margaret Markham, Chesapeake Conservancy
The annual Eastern WV Panhandle GIS Users Group Forum was held on September 14th, 2016 with 51 people attending. The one-day conference was organized by a committee from Jefferson County GIS and included sponsors from the WV Association of Geospatial Professionals and Eastern Panhandle Regional Planning and Development Council. Speakers presented on topics such as implementing parcel fabric in WV, using GIS for regional economic development, trends in GIS tools, integrating survey data into GIS, local contributions to state/federal datasets, evaluating riparian buffers, GIS for field mobility, and high accuracy data collection. Follow up contact information was provided for Jefferson County WV GIS.
The agenda outlines a day-long GIS Users Group Meeting taking place on September 14, 2016 in Martinsburg, WV. It includes sessions on implementing parcel fabric in WV, using GIS in regional development, tools and trends in GIS, integrating survey data into GIS, local contributions to state/federal datasets, evaluating riparian buffers, GIS for field mobility, high accuracy data collection, and stream delineation. The meeting runs from 8:30am to 4:00pm at The Purple Iris restaurant. RSVPs were requested by September 13, 2016.
Presented at the 2016 Eastern Panhandle GIS Users Group Meeting held on September 14 in Martinsburg, WV. Contributors Kurt Donaldson, Todd Fagan, & Aaron Cox.
The agenda provides the schedule for a GIS Users Group meeting taking place on September 2, 2015 from 8:00am to 3:15pm at the South Branch Inn in Romney, West Virginia. There will be presentations on topics such as updates from the state GIS coordinator, detecting change using ConnectAssessment software, parcel management, device locational accuracy, transitioning web applications to Web AppBuilder, interactive mapping, and using GIS for stormwater management and reporting. The agenda also lists times for registration, breaks with refreshments, and lunch.
This document discusses stormwater management and GIS applications. It covers MS4 permit requirements, construction stormwater permits, ordinance compliance, flood management, and the Chesapeake Bay TMDL. The document provides information on using GIS to track best management practices (BMPs) to treat stormwater runoff and reduce pollutant loads. It also summarizes observed land use changes and their impacts on nutrient and sediment loads in the Chesapeake Bay watershed. Resources on stormwater design guidance, erosion and sediment control, and watershed protection are also referenced.
The West Virginia Association of Geospatial Professionals held their annual meeting on June 3rd, 2015 at the Days Inn in Flatwoods, West Virginia. The agenda included welcome remarks, presentations on statewide GIS coordination, the National 3D Elevation Program, geospatial initiatives from a national perspective, and various geospatial projects in West Virginia. There was also a membership meeting, breaks for networking, and subcommittee meetings.
This document summarizes a workshop about coordinating West Virginia's participation in the USGS 3D Elevation Program (3DEP). The workshop provided an overview of 3DEP and the Broad Agency Announcement (BAA) process for funding lidar acquisition projects. It encouraged collaboration between federal, state, and local stakeholders to submit coordinated proposals. The document outlines the goals and timeline of 3DEP as well as resources for learning more about the program and tools for identifying areas of interest.
This document summarizes the Three Rivers QUEST program from 2009-2016 that monitored total dissolved solids (TDS) levels in western Pennsylvania rivers. It provides background on high TDS events in 2008 that led to water intake shutdowns. The program's funding sources and monitoring sites are described. Methods for managing and visualizing the water quality data are also outlined, including manual entry, importing files, and using GIS mapping tools.
This document provides summaries of recent geospatial initiatives from a federal perspective. It discusses updates from the National Geospatial Advisory Committee (NGAC), including their guidance topics for 2015. It also summarizes the Coalition of Geospatial Organizations (COGO) and its member organizations. Additionally, it outlines the Management Association of Private Photogrammetric Surveyors' (MAPPS) initiatives including their support for the USGS 3D Elevation Program and comments submitted to the FAA on drone regulations. It concludes with details on Woolpert's drone program, including the systems and vehicles they use and their strategy for both consulting services and data acquisition/processing.
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3. Project Overview
• LiDAR Acquisition Scheduled for Winter/Spring 2012
• LiDAR Acquisition is 100% Complete
• Products are currently being delivered as they are completed
• Collection designed to meet FEMA needs and USGS V13
Specifications for LiDAR
4. Project Overview- Specifications
• Nominal Pulse Spacing < 1 meter
• Vertical Accuracy
– RMSEZ 12.5 cm
– Fundamental Vertical Accuracy (FVA): 24.5 cm
– Consolidated Vertical Accuracy (CVA): 36.3 cm
– Supplemental Vertical Accuracy (SVA): 36.3 cm
• Relative Accuracy
– Within an Individual Swath ≤ 7 cm
– Between Swaths ≤ 10 cm
5. Project Overview- Specifications
• Spatial Reference System
– Horizontal
• North American Datum of 1983
• UTM Zone 18N
• Meters
– Vertical
• North American Vertical Datum of 1988
• Geoid 2009
• Meters
6. Project Overview – Specifications
• Breaklines
– Inland Ponds and Lakes:
• 2 acres or greater
• Flat and level (each vertex must have the same elevation)
• Water surface must be at or just below adjacent ground
– Inland Streams and Rivers:
• 100’ nominal width
• Flat and level bank to bank
• Should flow continuously downhill (monotonic)
7. Project Overview - Specifications
• LiDAR Classification
– LAS format (v1.2) with ASPRS classification scheme
• Class 1 – Processed, Unclassified
• Class 2 – Bare-Earth, Ground
• Class 7 – Noise (High/Low Points)
• Class 9 – Water (Classified Using Breaklines)
• Class 10 – Ignored Ground (Breakline Proximity)
8. Project Overview – Deliverables
• Raw Point Cloud
– LAS V1.2
– Georeference Information in Header Files
– GPS times recorded as Adjusted GPS Time
– Intensity Values
– Full Swaths
– Size not to exceed 2GB per swath
9. Project Overview - Deliverables
• Classified Point Cloud
– LAS V1.2
– Meet V13 Specifications for Classification (The new V1 specs are now
out)
– Tiled at 1500 m x 1500 m to U.S. National Grid
• Bare Earth Surface (Raster DEM)
– Cell Size of 1 meter
– ERDAS .IMG format (32-bit floating point)
– Depressions/Sinks not filled (Hydro-flattened DEM not Hydro-enforced
DEM)
10. Project Overview - Deliverables
• Control
– Supplemental Ground Control – Used to control the LiDAR collection
and processing
– Ground Control Quality Checkpoints
• Minimum of 20 points across 5 land cover types
– Bare Earth/ Open Terrain
– Urban
– Tall Weeds/Crops
– Brush and Trees
– Forested
• Must be on flat or uniformly sloping terrain
11. Project Overview - Deliverables
• Metadata
– FGDC Compliant
– Overview of processing steps and procedures
• Project Report
– Detailed records of collection, production, and quality assurance
processes
12. Project Overview - Schedule
Deliverable Description Due Date Status
Mobilization 12/16/2012 Complete
LiDAR Acquisition 03/09/2012 Complete
Survey (QA/QC Points) 02/10/2012 Complete
LiDAR Calibration 05/11/2012 Complete
Pilot Deliverable 05/25/2012 Complete
Full Deliverable 11/15/2012 In Progress
Final Acceptance 12/15/2012
13. Project Overview - Contacts
• USGS State Liaison – Craig A. Neidig
Charleston, WV
304-347-5130 x237
cneidig@usgs.gov
• USGS Project Manager – Patrick Emmett
Rolla, MO
573-308-3587
pemmett@usgs.gov
• Dewberry – Josh Novac
Tampa, FL
813-421-8632
jnovac@dewberry.com
15. What is LiDAR
• Light Detection and Ranging
• Active Scanning System
– Uses its own energy source to produce pulses of laser
(light) which are emitted, reflected and then received from
surfaces
• Measures range distances
– Based on time between emission, reflection and receive
time
• Direct terrain measurements, unlike photogrammetry
which is inferred
• Day or night operation except when coupled with
digital camera
• In addition to ranging, LiDAR systems can provide:
– Additional information about the target (for classification)
– Information about the transmission path (e.g. DIAL to
measure concentration of elements in the atmosphere)
16. What LiDAR is NOT
• The answer to all your elevation requirements
• All-weather
– Target must be visible within the selected EM spectrum
– No rain or fog
– Must be below clouds
• Able to “penetrate vegetation”
– LiDAR can penetrate openings in the vegetation cover but
cannot see through closed canopies
17. Airborne LiDAR System Components
LiDAR Transmitter, Scanner, and
Receiver
Aircraft Positioning – Differential
GPS (with post-processing)
Aircraft Attitude – Pitch, Roll, Yaw –
Inertial Navigation System (GPS-
Aided)
Data System
18. Operating Wavelengths
Wavelength (not to scale) 100µm
0.0001µm 0.01µm 0.2µm 0.3 0.4 0.7 1.5 5.6µm 20µm 100µm 1cm 10cm 1m
0.1cm
Gamma X-Rays Ultraviolet Visible Infrared Microwave TV/Radio
Rays
Passive Microwave
Film Active RADAR
Electro-optical Sensors
Thermal IR
In theory, any light source can be used to create a LiDAR instrument
Near-Infrared wavelength
Used by most airborne terrestrial LiDAR systems
Easily absorbed at the water surface (unreliable water surface reflections).
Wavelengths utilized: 1000 – 1500 nm
Blue-Green Wavelength
Used by all airborne bathymetric and “topobathymetric” systems (532 nm)
Can penetrate water, but signal strength attenuates exponentially through the
water column
19. Laser system characteristics
• Pulse width (or duration) is usually defined as the time
during which the laser output pulse power remains
continuously above half its maximum value (FWHM).
Pulse width
intensity
“short”
pulse
“long” pulse
time (ns)
pulse width
20. Multiple Scanning Patterns (two most common)
It is common to withhold the data for a
few percent at the tips of the zig-zags
where elevations are less accurate
21. Various LiDAR Formats
Threshold
Short Duration
Laser Pulse
Digitized Discrete Pulse- Photon
Backscatter Return Width Counting
Waveform Leading-
Edge
Image courtesy Dave Harding, NASA
22. Discrete return vs. waveform-resolving and the “dead zone”
effect
Discrete-return LiDAR Waveform-resolving LiDAR
most discrete-return systems require a minimum vertical object separation to
register consecutive returns from the pulse separately, thereby being blind to
canopy material within this dead zone
33. LiDAR Data Processing Workflow
DGPS Data
Lidar range
Calibration and
IMU Data mounting
Scan Angles
parameters
Post-processed GPS trajectory and INS
solutions
Point Cloud Data
X, Y, Z data
34. Data Processing Steps
• Initial processing done in field
• Process GPS/IMU
• Process calibration data
• Process waveform data (if available)
• Process full point cloud to calibration
• Verify data (i.e. flight line comparison, coverage,
accuracy, etc.)
• Post Processing – Classification; auto and manual
filtering
35. LiDAR: Raw Data Processing
• Data collected by flight
• Monitored during collection
– Sensor operation
– Flight line holidays
– Data voids
– Gross data errors
• Calibration flight at start and end
of flight for adjustment of system
and systematic drift
• GPS Data processing (kinematic
post-processing aircraft GPS to
reference station)
• Results in X Y Z, Scan Angle,
Intensity, Return# ASCII or Binary
files – Typically LAS
37. LiDAR: Post Processing - Classification
• Separating ground from non-ground
– Automated Processing
– Manual Processing
38. Post Processing - Classification
• Automated scripts
– Classifies approximately 80 – 85% and takes 20% of the time
– Algorithm must be balanced to classify correctly - May cut into slopes too
much, or leave too much artifacts
– Color coding orange = ground, green = other
39. Post Processing - Classification
• Manual Classification
– Impossible to classify to the 100% level
– Manual classification takes 80% of the post processing time (to get that last
20%)
– Color coding orange = ground, green = other
40. ASPRS Standard LiDAR Point Classes
Classification Meaning
Value
(bits 0:4)
0 Created, never classified
1 Unclassified
2 Ground
3 Low Vegetation
4 Medium Vegetation
5 High Vegetation
6 Building
7 Low Point (noise)
8 Model Key-point (mass point)
9 Water
10 Reserved for ASPRS Definition
11 Reserved for ASPRS Definition
12 Overlap Points
42. Elevation Data Challenges
• Large number of elevation records can require long processing
times
• Exploitation of LiDAR has typically required specialized software
such as
• GeoCUE
• QT Modeler
• Terrascan/Terramodeler
• Many new LiDAR programs are being introduced which will allow more
users access to the data
• ArcGIS – Version 10.1
• FugroViewer – Free
• LAS Reader for ArcGIS – Free
• PointView LE - Free
43. LiDAR Software Tools
• ArcGIS (10.1)
• Geocue (Geocue)
• LP 360 (GeoCue)
• Quick Terrain Modeler (Applied Imagery)
• Terrascan (Terrasolid)
• LASTools
• FugroViewer
Sample list – no endorsement is inferred or implied
45. Data Verification & Quality
Three fundamental questions MUST BE
ASKED
1. Did the LiDAR system work
2. Are the data classified properly and free of
artifacts to support the intended product?
3. Is the dataset complete?
46. Types of Analysis
• Quantitative Analysis
– Utilize survey checkpoints to verify TIN accuracy
– FEMA only “requires” quantitative analysis
• Qualitative Analysis
– Subjective analysis to assess the quality which can include
cleanliness, usefulness for the intended product etc.
• Completeness
– Are tiles complete with no voids, correct location,
projection information, classified to the correct classes etc.
49. Quantitative Verification
• Ground truth surveys
– Utilize GPS and conventional survey checkpoints (cp)
– Place checkpoints in strategic locations based on flight line pattern
– Verify data in varied land cover categories
– Compare CP with interpolated TIN value
50. Qualitative Assessment - Techniques
• Utilize different software and tools
• Use imagery
• Create pseudo imagery •
•
• Combine images or techniques •
•
•
•
•
•
•
•
52. Intensity Images
• Measures the amount of light
returning to the sensor
• Useful for QA/QC & Research
– Identify conditions at time of
collection
• Can be used for stereo-
compilation to generate 3D
breaklines
(“LiDARgrammetry) or 2D
features
53. Breaklines
• Linear features that control surface behavior
• Can be 2D or 3D
• Traditionally derived from stereo photogrammetry or from
surveys
• Can use LiDAR and Intensity to create breaklines
• 2D breaklines with assigned elevations for hydro-flattening are
typically used.
54. Terrain Dataset
A Terrain Datasets is a multi-resolution
TIN-based surface build on-the-fly from
feature classes stored in a feature dataset
of a geodatabase.
Terrain Datasets are more effective for
storing and visualizing large point data
sets.
A Terrain Datasets resides in the same
feature dataset where the feature classes
(used to construct it) reside.
Terrain Datasets can be used to obtain
TINs and grids.
55. Terrain Dataset
In a Terrain Dataset, feature classes
include:
Mass points (e.g., LiDAR);
Breaklines (hard and soft);
Clipping polygons (hard and soft);
Erase polygons (hard and soft);
Replace polygons (hard and soft).
A Terrain Dataset is composed of a series
of TINs, each of which is used within a
map-scale range. For each map-scale
range, a level of detail (i.e., z resolution)
and pyramid level are defined.
56. Different Treatments of LiDAR DTMs and DEMs
• Traditional Stereo DTM (Topographic Surface)
• Pure LiDAR (Topographic Surface)
• Hydro-Flattened (Topographic Surface)
• Full Breaklines (Topographic Surface)
• Hydro-Enforced (Hydrologic Surface)
• Hydro-Conditioned (Hydrologic Surface)
57. Traditional Stereo DTM (Topographic Surface)
• Reference image of the
traditional stereo-
compiled DTM
• Built from Masspoints
and Breaklines
• Much coarser resolution
than LiDAR
• Demonstrates the familiar
and usually expected
character of a
topographic DEM
• Most notably, the “flat”
Stream Waterbody water surfaces
58. Pure LiDAR (Topographic Surface)
• DEM created only using bare-
earth LiDAR points
• Surface contains extensive
triangulation artifacts
(“TINning”).
• Cause by the absence of:
– LiDAR returns from water
– Breakline constraints that
would define buildings, water,
and other features (as in the
Stereo DTM).
• Aesthetically and
cartographically unacceptable
to most users
TINning in Water Areas
59. Hydro-Flattened (Topographic Surface)
• The goal of the v13 Spec
• Intent is to support the development of
a consistent, acceptable character
within the NED
• Removes the most offensive pure LiDAR
artifacts: those in the water.
– Constant elevation for waterbodies.
– Wide streams and rivers are flattened
bank-to-bank and forced to flow
downhill (monotonic).
• Carries ZERO implicit or explicit
accuracy with regards to the
represented water surface elevations –
It is ONLY a cartographic/aesthetic
enhancement.
• Building voids are not corrected due to
high costs
• Most often achieved via the
development and inclusion of hard
Stream Waterbody breaklines.
60. Full Breaklines (Topographic Surface)
• A further possible
refinement of the hydro-
flattened surface
• Removes artifacts from
building voids
• Refines the delineation of
roads, single-line
drainages, ridges, bridge
crossings, etc.
• Requires the development of
a large number of additional
detailed breaklines
• A higher quality topographic
surface, but significantly
more expensive.
Buildings Roads • Not cost effective for the
NED.
61. Hydro-Enforced (Hydrologic Surface)
• Surface used by engineers in
Hydraulic and Hydrologic
(H&H) modeling.
• Similar to Hydro-Flattened
with the addition of Single
Line Breaklines: Pipelines,
Culverts, Underground
Streams, etc…
• Terrain is then cut away at
bridges and culverts to model
drain connectivity
• Water Surface Elevations
(WSEL) are often set to known
Culverts Cut Through Roads values (surveyed or historical).
62. Hydro-Conditioned (Hydrologic Surface)
• Another type of surface
used by engineers for H&H
modeling.
• Similar to the hydro-
enforced surface, but with
sinks filled
• Flow is continuous across
the entire surface – no
areas of unconnected
internal drainage
• Often achieved via
ArcHydro or ArcGIS Spatial
Analyist
63. Common Data Upgrades to USGS V13 Spec.
1. Independent 3rd party QA/QC
2. Higher Nominal Pulse Spacing (NPS)
3. Increased Vertical Accuracy
4. Full waveform or topo/bathy collection with red/green lasers
5. Tide coordination, flood stage, plant growth cycle, shorelines
6. Top-of-canopy (1st return) Digital Surface Model (DSM)
7. More detailed LAS classification for vegetation, buildings
8. Hydro enforced and/or hydro conditioned DEMs
9. Single-line hydro feature breaklines; other breaklines
10. Building footprints with elevations/heights
11. Additional data products such as contours
64. Generating Contours from LiDAR
Contours are produced
Not aesthetically pleasing from LiDAR mass points
and breaklines
65. ASPRS’ “DEM Users Manual”
1. Intro to DEMs, 3-D Surface Modeling,
Tides
2. Vertical Datums
3. Accuracy Standards
4. National Elevation Dataset
5. Photogrammetry
6. IFSAR
7. Topographic & Terrestrial Lidar
8. Airborne Lidar Bathymetry
9. Sonar
10. Enabling Technologies
11. DEM User Applications
12. DEM Quality Assessment
13. DEM User Requirements
14. Lidar Processing & Software
15. Sample Elevation Datasets
66.
67. Final Report for NEEA Study available at
www.dewberry.com
http://www.dewberry.com/Consultants/GeospatialMapping/FinalReport-
NationalEnhancedElevationAssessment
68. THANK YOU
Josh Novac
Project Manager
Remote Sensing Services Line
Dewberry (Tampa, FL)
jnovac@dewberry.com
Ph: 813.421.8632