School of Surveying and Spatial Information Systems
The University of New South Wales
Mobile Mapping System: Concept & Current Development
by Wei. H Chan
Supervised by Dr. Jinling Wang
This research reviews the evolution of Mobile Mapping System (MMS) from photolog pictures to the current modern multi-sensor data acquisition systems that support different platforms. Different positioning techniques used in MMS are examined with emphasis on GPS/INS integration, while the preferred sensors use is also highlighted.
The backbone technology for MMS, direct georeferencing, is reviewed with experiments conducted by various research groups. System calibration is one of the important factors that influence the accuracy of MMS. This is also discussed in depth. The different aspects that will be expected to benefit MMS in future are also discussed. In addition, a collection of literature related to MMS is compiled and presented by a webpage.
The concept of Mobile Mapping has evolved over the last decade to improve the efficiency of spatial data collection and it is designed to be installed on various land based and airborne platforms.
The aim of this project is:
(a) to review the historical development and current status of MMS,
(b) to discuss the basic concepts and principles, and
(c) to analyse the factors that affect its performance and future trends.
A Mobile Mapping System (MMS) can be defined as a kinematic platform, upon which multiple sensors have been integrated and synchronized to a common time frame, to provide three-dimensional near-continuous and automatic positioning of both the platform and simultaneously collected geo-spatial data.
the present time, spatial data are highly in demand for the inputs into GIS
(Geographical Information System) databases. Traditional techniques of data
collection, such as using total stations, are too expensive or time consuming
and aerial photographs on the other hand could not provide sufficient detailed
information. Therefore, to find a way to capture data efficiently is important
to generate new databases and to update existing databases for applications such
as highway and facility mapping, roads inventory, natural resources inventory,
utility management and city planning.
The main components of MMS are the navigation and imaging sensors. The most important aspect for MMS is direct georeferencing. This is made possible due to the integration of GPS and INS to provide exterior orientation with six parameters: projection centre coordinates (X0, Y0, Z0) and the rotations around the three axis omega (ω), phi (φ) and kappa (κ) of the mapping sensor without having any ground control points. Figure 1 shows an example of a land-based MMS GPSVisionTM from Lambda Tech International. This is particularly useful for aerial photogrammetric mapping as it eliminates the traditional aerial triangulation, which is labour and time intensive. An integrated Kalman filter is then applied to combine the GPS and inertial solutions.
Figure 1: Land based MMS GPSVisionTM from Lambda Tech International
Major Components of MMS
MMS consist of two major components: namely the positioning and imaging sensors. The positioning component mainly comprises of GPS and INS. In addition, other dead reckoning sensors such as odometer and digital magnetic compass, are used for integration to perform direct georeferencing. The imaging sensors may be in a form of digital (CCD) based or video cameras, Laser Range Finder, LIDAR, InSAR and Multi/hyper spectral sensors (airborne systems) . Table 1 summarised the primary sensors and functionality of MMS.
Table 1: Primary sensors and their functionality
The development of
MMS has gone through major changes from photolog to multi-sensors systems
integration with the ability to support kinematic platforms in land and airborne
environments. Integration of INS/GPS is the preferred positioning technique to
perform direct georeferencing as it is able to support high accuracy imaging
sensors that operated in a continuous scanning mode such as a laser scanner.
One of the most
important factors that influenced the accuracy of direct georeferencing is
sensors calibrations. It is important that all sensors are well calibrated,
especially boresight misalgnment, and referenced to a common coordinated frame.
The high cost of MMS is mainly due to the high price of INS components and the large CCD chip. However, the cost is likely to drop as the MMS community is becoming bigger and will continue to expand. The trend of MMS is moving towards low cost, advanced real time image processing, automated data flow and fast wireless transfer of spatial data. All these can be expected in the future as enhancement of third generation wireless technology 3G, mobile GIS, telegeoinformatics and Galileo progresses.
The following links are some companies, universities and conference/journal papers that related to MMS.
Applanix Corporation,Canada - Integrated inertial/GPS products for commercial applications
ARRB Transport Research, Australia - Australia's leading provider for value-added research and technical services addressing transport problems
Ingenieur-Gesellschaft für Interfaces mbH (IGI), Germany - Integrated inertial/GPS products for commercial applications
Ohio State University, Columbus, USA - Centre For Mapping
University of Calgary, Canada - Satellite-Based Positioning and Navigation Group, Department of Geomatics Engineering
University of New South Wales, Sydney, Australia - Satellite Navigation and Positioning Group, School of Surveying and Spatial Information System
Grejner-Brzezinska D., Li R., Haala N., and Toth C. (2002). Multi-Sensors System For Land-Based and Airborne Mapping: Technology Of The Future?, ISPRS Commission II, Symposium, Xi'an, China August 20-23.Download
Cramer, M., Stallmann, D. & Haala, N. (2000). Direct Georereferencing Using GPS/Inertial Exterior Orientations for Photogrammetric Applications. IAPRS Vol. XXXIII Part B3/1 pp. 198-206. Amsterdam. 2000. Download
For more information, please contact:
Dr. Jinling Wang
School of Surveying and Spatial Information Systems
University of New South Wales
UNSW SYDNEY NSW 2052