ISPRS Commission I Symposium
Calgary Alberta, Canada
Pre-Conference Tutorial
June 14th, 2010
Instructors:
Naser El-Sheimy and Mohamed MR Mostafa
Image Georeferencing is defined as the science and art of referencing remotely sensed data to a local mapping frame of reference. Traditionally, this has been done using photogrammetry, ground truth and various forms of triangulation, resulting in the production of quality mapping products.
In 1984, a group at the University of Calgary conducted the first experiment using GPS onboard a survey aircraft to measure the camera location at the moment of exposure. This certainly revealed the enormous potential of this new technology. The 1990s saw the use of Kinematic GPS with GPS-assisted Aerotriangulation (AT) become standard, and the appearance of the first GNSS-Aided Inertial systems being tested to augment or even replace traditional photogrammetric Aerotriangulation altogether. By the late 1990s, GNSS-Inertial systems were themselves proven to be commercially viable methods of georeferencing, driven in part by the demands of new types of sensors such as Lidar, digital line scanners and SAR where AT was not practical. Nowadays, direct georeferencing using GNSS-Inertial is a standard method of georeferencing data collected on mobile platforms.
This workshop will focus on the underlying concepts of image georeferencing using different imaging sensors for different airborne and land applications. Practical examples from real world projects are used extensively to illustrate the pros and cons of each method or sensor assembly. This workshop is intended for the Geomatics professionals from either technical or business background. The following topics will be covered in this workshop:
1. Photogrammetry: The Concepts
·
Basic geometry
·
Aerotriangulation
·
Commercial Digital
Cameras
2. GNSS and Inertial Sensors
·
GNSS basics
·
Inertial basics
·
GNSS-Inertial
Integration
·
Accuracy aspects
·
Best practice for
GNSS-Inertial Data Processing
3. Direct Georeferencing
·
Basic concepts
·
Applications to
mobile sensors
·
Quality control
·
Best practice
4. Applications in Mobile Mapping
·
Special airborne
applications
·
Land applications
·
Marine Applications
·
Data integration
5. Future Trends
·
GNSS
·
Inertial Sensors
·
SLAM
·
Real-time mapping
·
Integrated sensor
orientation - redux
Instructors:
Ayman Habib and Bryan Mercer
LiDAR Mapping
Recently, Light Detection and Ranging (LiDAR) systems have emerged as a fast, accurate, and cost-effective technology for direct acquisition of highly dense 3D positional data from physical surfaces. The widespread adoption of LiDAR systems has been propelled by the improved performance and lower cost of modern direct geo-referencing technology (Global Navigation Satellite Systems – GNSS, Inertial Measurement Units – IMU, and GNSS/IMU integration techniques). A LiDAR system is a combination of two main components: the direct geo-referencing and laser ranging components. The direct geo-referencing component provides the position and the attitude of the mapping platform. The laser ranging component, on the other hand, provides the distance between the laser beam firing point and its footprint. The geo-referencing and ranging information are combined to provide the ground coordinates of the laser beam footprints leading to a highly dense and accurate point cloud covering the mapped area.
The main objective of this stream of the workshop is to provide an overview of LiDAR principles, mathematics, error sources, quality assurance and quality control procedures, data processing techniques, and applications. The following list provides the covered topics:
InSAR:
This stream of the workshop will be present an introductory level for those who have little knowledge of Interferometric SAR (InSAR or IFSAR) but would like to attain a basic understanding of the underlying principles, flavours, emerging applications and future of the technology. The major topics will include: