Airborne laser scanning or laser is one of the most effective and perspective methods of 3 D acquisition for large scale topographical mapping.

In 2006 SRIDS “InjGeo” purchased airborne laser scanner ALTM-3100 of Optech Inc., Canada.

Presently this system is one of the most technically advanced and cost efficient laser mapping system.

Using of laser scanner system ALTM-3100 allowed to considerably reduce man-hours, material resources, periods of field topographical surveys and to increase quality of products comparative to traditional topographical survey.

Basic functional components of airborne laser scanning system are as follows:

• Scanning unit (generation of laser impulses, receiving echo signals and definition of slant distance up to the point of reflection, scanning control);
• Airborne navigation set (real time overlapped data processing of GPS receiver and inertial system IMU, provision of every first laser mapping sensing with complete set of elements of exterior orientation, which allows to determine geodetic coordinates of ground points which reflect direct laser impulses);
• Network of terrain base GPS-GLONASS stations (differential correction of aircraft GPS and GPS-GLONASS data receivers).

Scanning unit

Airborne navigation set

Laser scanning technology allows to create high precision:

• digital models of territory and complicated engineering facilities,
• digital models of terrain,
• orthophotomaps.

Since “InJGeo” has purchased airborne system for Laser cartography ALTM-3100, engineering survey works do not require involvement of great amount of specialists, material resources and long time periods.

Survey complex used by “InjGeo” includes laser scanner (sensor, control block), direct geopositioning system, digital camera, pilot display, note book, software for primary data processing (Applanix POSPac) and for modeling and layout composition (Altexis, Microstation (Terra), Civil 3D, Erdas Imagine).

Main advantages of «ALTM 3100» laser system:

• Fixing of intensiveness of reflected signal (night time operation).
• Fixing up to 4 reflections from one sounding impulse (ability to distinguish tree tops from ground surface).
• High output, up to 1000 km 2 per working day.
• Compatibility with digital airborne cameras and other aviation picture sensors
• Possibility to use GPS receivers and GPS/GLONASS of various manufacturers.
• Availability of coordinated scheme of installation at domestically manufactured aircrafts.
• Adaptation to Russian conditions .
• Economical effectiveness to use at the conditions when other methods are extremely difficult to apply, impossible or restricted by season factors (non-orientated terrain, continuous foliage, vary flat relief, ets).

« ALTM 3100» laser system performs not only fast scanning of object surface, but shows abnormalities.

Unique possibilities of airborne laser locating system allows to receive :

• actual relief of land surface ( even under tree tops in forest) not loosing accuracy;
• location and shape of complicated structure objects, for example processing platforms and pipelines, edifices and other facilities as well as abnormity ;
• topographic layouts and schemes of reference land (tundra , totally snow covered territory, deserts, sand beaches) with such an accuracy and detail information unachievable by means of other methods.

Work peculiarity of specialists of InjGeo is that they perform laser scanning works instead of traditional topographic survey.

This method is most advantageous since with the minimum expense and time periods it provides high performance of field activities which consequently makes engineering survey and design activities cost effective, high quality and time saving.

Arrangement of soft/hardware complex «System of real time mapping at ALTM 3100 base»

• Possibility to install at any light helicopter or plane.
• Availability of MI-8 designer coordination scheme
• Duration of installation and metrological control process is within one day.

Measuring of set up parameters of scanning block and digital camera:

• Calculation of set up parameters is made by Off-Setter program.
• All measurements for the program are performed with required precision.
• Measurement of spatial values, specific points is made with GPS facilities in local auxiliary coordinate system without reference to federal feodesic system of coordinates i.e eventually measuring distances but not coordinates which considerably simplifies the task.

SRIDS “InjGeo” EXPERIENCE TO USE AIRBORNE LASER SCANNING

From May 2006 SRIDS “InjGeo” performed airborne laser scanning operations for the following projects:

• «Oil pipeline system Khariaga – Indiga»,
• «Grounds for investments into complex development of Shtockman gas/condensate field project”,
• «Debottlenecking of East Siberia – Pacific ocean pipeline system»,
• «Development projects of Sochi. Making up topographical plans of 1:2000 scale»,
• «Construction of federal motor road Dzhubga – Sochi up to Georgian boarder line by-passing Tuapse, 50-72 km»,
• «Pochinki – Griazovets gas pipeline»,
• «Making up orthophotoplans and topoplans at 1:2000 scale for residential areas of Tuapse district (Olginka village and Semiglavaya mauntain, option 2),

«Making up topoplan at 1:2000 scale for crush stone pit, Krivenkovskoe village».

Scope of the jobs completed for the following projects: