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3D Modeling with High Resolution LIDAR

I created and presented this poster featuring LIDAR Color Shaded Relief model of Bouctouche / Shediac area of New Brunswick at the 2004 Geotech event that was held in Toronto.

UTM Rows and Zones

These UTM key maps can easily help you find out what UTM zone you are working from. Simply click on the map to enlarge it to expose all of the map, then find out where you are located and look for the zone and row that matches your area.

Using Google Earth to obtain NGS CORS site information

Every now and then I come across some little utilities that help to make things easier while working in the field and these pages are mainly my way of sharing them with others while creating a go-to place where I can easily find them when I need them.

Here is a Google Earth file that that contains locations and basic information about all of the National Geodetic Survey (NGS) Continuously Operating Reference Stations CORS. Saving you time from searching for CORS stations in your area and finding out what sampling rate they record GPS data at.

Bouctouche New Brunswick LIDAR

I created and presented the following poster displaying LIDAR CSR surface modeling of Bouctouche, New Brunswick as part of my Applied Geomatics graduate work at COGS in 2004. The inset is a 3D perspective view of the image represented by the large blue arrow.

LIDAR surface modeling of Bouctouche New Brunswick

Color Shaded Relief Models

Traditional images in geomatics are often two dimensional, meaning that all data in the image can be referenced by X and Y coordinates.
Three dimensional color shaded relief (CSR) perspective view of high resolution LIDAR

Three dimensional images (3D) incorporate a third dimension (the Z component) which represents the elevation or depth aspect of the data. To incorporate it into an image requires creating special geomatics value added products that allow users to perceive the presence of the third dimension into a traditional two dimensional setting (because most paper and computer screens are flat or two dimensional).

A color shaded relief (CSR) utilizes chromo stereoscopic techniques to help emphasize the depth of the Z dimension from traditional shaded relief models that already portray the presence of an elevation difference. Using carefully edited RGB (red, green, blue) pseudo colors and then encoding them into the shaded relief image provides the user with an even more enhanced feeling that they can perceive a third dimension from a two-dimensional medium (also helping to quickly decipher between high and low elevated regions). When a feature of the same color in the image is shaded darker than the shade of its background, then the background color will predominate in determining its perceived depth position in the image.

Color shaded reliefs utilize chromo stereoscopic techniques to help emphasize the depth of the Z dimension from traditional DEMs

There are several different software packages that can be used to create CSR models, but I have found that Geomatica software by PCI Geomatics has proven to produce some of the better results in CSR models generated from DEMs. ChromaDepth 3-D glasses can often be used to further enhance the three dimensional feeling as well. These glasses use sophisticated micro-optics technology to transform color images into stereo 3-D. If you do not currently have PCI Geomatica then you can obtain a trial copy of it from their web site; then follow the steps outlined in the following CSR tutorial.

Here are some more Examples of some of the many color shaded relief (CSR) models that I have created

Orthophoto & LIDAR CSR for New Brunswick

Color Shaded Relief related documents:

 

Digital Elevation Models (DEMS)

Digital elevation model (DEM) of Lismore, Nova Scotia

A digital elevation model (DEM) or sometimes referred to as a digital terrain model (DTM) is a quantitative representation of the topography of the Earth (or sometimes other surfaces) in a digital format. They are a common component of geographic information systems /remote sensing and are usually represented by cartesian coordinates and numerical descriptions of altitude. In contrast with topographical vector maps, the information is stored in a raster format. That is, the map will normally divide the area into a rectangular grid of cells or pixels and store the elevation of each one as a DN value.

Traditionally most common DEMs used in the Geomatics industry only contain elevation values of the true ground’s surface but DEMs can also sometimes contain other features found upon the ground’s surface as well. When it contains all features it is often referred to as a digital surface (DSM). Digital surface models contain elevation values representing the ground as well as any other objects such as buildings and trees.

The resolution of the DEM, or the distance between adjacent grid points (often the size of the cell or pixel), is a critical parameter in determining the amount of detail that a user should except to represent in the DEM. The smaller the resolution, the more details or features that will be present, e.g. a 1 m resolution DEM will contain more details then a 20 m one and be better suited for hydrological analyses.

DEMs are used as a source of elevation (and to create other digital terrain models) for many different purposes such as:

  • to orthorectify imagery
  • as a source of topographic information and to create contour lines from
  • to identify geological structures in topography
  • to identify risk areas and hydrological flow patterns
  • to identify flood risk areas
  • to determine accessibility
  • to identify regions of visibility for radio or cell towers
  • to predict how the terrain can effect signal strength and reflection
  • and many more uses

Digital elevation models may be prepared in a number of ways, but they are frequently obtained by remote sensing rather than direct survey. Older methods of generating DEMs often involved interpolating digital contour maps from aerial photography produced by direct survey and interpretation of the surface.

Many mapping agencies produce their own DEMs, often of a higher resolution and quality, but frequently these have to be purchased, sometimes at considerable cost. The two methods of creating DEMs that are covered on this web site deal with LIDAR and Photogrammetry methods.

 

Digital Terrain Modeling

Digital Terrain Modeling is the process of simulating or representing the relief and patterns of a surface with numerical and digital methods. It has always been an integral component to geology related fields such as geomorphology, hydrology, tectonics and oceanography but over the past decade has also become a major component to non geophysical applications such as GIS modeling, surveying and land use planning.

Terrain Models are derived from data represented by digital elevation models (DEMs) and can include shaded relief models, slope and aspect models, perspective scene generation, and drainage basin analysis (and other models).

3D Flood Modeling with LIDAR

This is a summary detailing the methodologies and issues involved during an extensive technical graduate project that I completed as part of the Applied Geomatics Research program with the Center of Geographic Sciences (COGS) and the Applied Geomatics Research Group (AGRG).LIDAR Color Shaded Image of Pointe du chene New Brunswick with modeled January 2000 Flood maps layered ontop

The main goal of the project was to generate flood maps and DEMs with better than 30 cm vertical accuracy for the coastal area of southeastern New Brunswick in support of CCAF Project A591. The CCAF project was a venture partnered with Environment Canada, Geological Survey of Canada, Natural Resources Canada, New Brunswick Resources and Energy, Parks Canada, Universite de Moncton, Nova Scotia Community College (AGRG & COGS) and the University of New Brunswick. The aim of the CCAF project team was to collaborate together and generate accurate maps and information that would quantify the impacts of climate change, sea-level rise, storm surge events and coastal erosion in support of sustainable management and the development of adaptation strategies.

The project involved mapping areas at risk to coastal flooding from storm surge events. High resolution elevation data acquired from an airborne LIDAR sensor was used to interpolate three dimensional digital elevation models of the coastal topography and to accurately model flooding for the selec

ted case study areas in southeast New Brunswick. Based upon the LIDAR DEM and the provided predicted sea-level rise information from storm surge and climate change models, several flood risk maps of the coastal zone of New Brunswick were produced.Further analysis of the spatial relationships between existing structures and land cover types and predicted flood risk maps will be done in collaboration with other sub-projects of the CCAF project committee.

The project was the major portion of the advanced diploma in Applied Geomatics Research that I obtained from the Center of Geographic Sciences (COGS). This web page is intended as a summary portfolio of the project, with links to the related components such as papers, presentations, posters, scripts, images etc.

STUDY AREA

2004 AGRG CCAF Key Map of LIDAR study areas in New Brunswick

The study area for the project consisted of the coastal Gulf Shore region of southeastern New Brunswick from Kouchibouguac National Park south to Jourimain Island. The area was split into ten smaller polygons, based on sub-project requirements of the CCAF team and comprised the areas of highest scientific interest and significant priority for governments and coastal stake holders.The polygons were given the following names: Kouchibouguac National Park,Cap Lumiere, La Dune, Bouctouche, Cormierville, Ile Cocagne, Cap Pele, Shemogue Harbour, Little Shemogue, and Cape Jourimain.

2004 AGRG CCAF New Brunswick LIDAR Study Areas integrated with a LANDSAT image

Literature Review

The literature review consisted of a paper and a presentation that took place during September and October of 2003 at the Applied Geomatics Research Group facility in Middleton, Nova Scotia.

Project Proposal

All students were required to construct a proposal for their respective projects even though we were basically all ready committed to complete the project and funding had already been secured prior to our presence. Also in my case, I was already 6 months into the project when I was writing the proposal. The project proposal consisted of a paper and a presentation that took place during September and October of 2003 at the Applied Geomatics Research Group facility in Middleton, Nova Scotia.

LIDAR equipment from the 2004 AGRG New Brunswick LIDAR mission including helicopter, IMU and LIDAR hardware

Final Paper and Presentation

The final paper was prepared to summarize the entire project, the report was rather lengthy with over 200 pages of content, the PDF version had to have all image resolutions degraded to allow it to be posted to the site and note that it is still relatively a large file (over 20 mb).

Final presentations were given at the CCAF annual general meeting at the University of Moncton in New Brunswick and the 2004 Geomatics Atlantic Conference at the University of New Brunswick in Fredericton, New Brunswick

Ortho photo of Shediac New Brunswick and a CSR model comparing the similarities of photogrammetry and LIDAR surfaces

Other Related Papers and Presentations

I have presented this project at the 2004 GeoTec Conference in Toronto, Ontario, the 2004 Geomatics Atlantic Conference and at the 98th Canadian Institute of Geomatics Conference in Ottawa, Ontario.

Three Dimensional Flood Modeling with High Resolution LIDAR presentation at the Canadian Institute of Geomatics 2005 Conference held in Ottawa, Ontario

Scripts

Several scripts were written for this project to aid with the automation of repeat data processing. EASI scripts were written and used with PCI and AML scripts were written and used with ESRI ArcINFO 9x workstation.

  • Bonnycastle A & MacKinnon E (2003) TERRA_IMPORT.aml based on previous AGRG AML script written by Christian M,Dickie S, & MacKinnon F
  • Bonnycastle A, MacKinnon E & Miline T (2003) TILE_GRID.aml
  • Bonnycastle A, MacKinnon E & Miline T (2003) TILE_GRID.aml – this version was designed to create the Allhits surface grids
  • MacKinnon E (2004) Flood_BT.mod – EASI script that was designed to create flood images of the LIDAR DEM (a different version was created for each study area)
  • MacKinnon E (2004) Flood_CP_anim.mod – EASI script that was designed to create flood images to incorporate into the flood animations (a different version was created for each study area)

Images

Images submitted to posted on the Environment Canada web site:

Animations

  • MacKinnon E (2004) Three dimensional flood simulation – This is a simulated flood from sea level to 5m integrated with a color shaded relief DSM
  • MacKinnon E (2004) Three dimensional fly over simulation – LIDAR All hits surface with a color orthophoto mosaic draped on top

Posters

Several posters were created for this project with some of them being presented at major
conferences. All posters were relatively large and hard to represent on a web site, so most cases these are low resolution graphic representations, and not meant to be the actual posters.

This poster titled 3D Modeling with High Resolution LIDAR was presented at the 2005 GeoTec Conference in Toronto

 

Related Links

COGS – (Center of Geographic Sciences)

AGRG – (Applied Geomatics Research Group)

Environment Canada

PCI Geomatics

ESRI

Leica Geosystems GPS

Canadian Institute of Geomatics

COGS Applied Geomatics Research Course Descriptions

5033 Research Methods

The primary objective of this course is to prepare the student to undertake his/her individual research in the second semester. The standard components in a research project are: literature review, methodology, proposal writing, and proposal presentation.

5035 Advanced Data Processing

The main data sets involved in this course will consist of information collected under the CFI funding. The data sets include: LIDAR, CASI, Ikonos and digital aerial photography. Other field data sets will be used and integrated with the analysis. Along with technical papers associated with the assignment data processing, each student will select a specific application of the data and make a presentation at the end of the term as well as write a technical report on his/her activity

5041 Directed Research Applications

This course is designed to provide students with the opportunity to engage in selected research applications. There will be requirements to conduct literature reviews, investigate specific software tools and techniques, and develop various graphical user interfaces and analytical tools.

6040 Research Project

The research project is a major component of the AGR program. It fully occupies the second and third semesters. During the first semester, as part of the normal course load, each student completes a research proposal. The proposal describes the research
problem, literature review, methodology, time lines and deliverables. Project management in the second semester includes weekly meetings with his/her supervisor and monthly presentations to the program research committee (all faculty). Many of the research projects involve collaboration with external clients. In which case, copies of
the proposal, deliverables and final report are given to the external client as well as maintained by AGRG. The research project meets the Work Experience requirements for the Applied Geomatics Research Program.

Portfolio Items