Triangulation Group5

8/10/2019 Triangulation Group5

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Content

Details of the group

Introduction

Preliminary preparation

Methodology

Computation procedure

Results and Discussion

Conclusions

Recommendations

References And Bibliography


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Details of the group

Station Name : Kataragama peak

Stations to be observed : Haburugala

Karambagala

Hambantota Tower

Coordinator : Mr. NMPM Piyasena.

Instructors : Mr. PGV Abeyratne.

Assistants : 02

Duration : From 22.02.2011 to 03.03.2011


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Details of the group Cont.

Group MembersJayawardana S.A.M.M. 07/SS/014

Laththeepan S. 07/SS/019

Prasanna S.A.C. 07/SS/030

Rathnayake R.M.P.B. 07/SS/033

Senarath K.M.M.S. 07/SS/035Suranga K.G.N.M.J. 07/SS/038

Thushiyanthan S. 07/SS/040

Vijayapragash S. 07/SS/041


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Introduction

What is Triangulation ?

A method of surveying; the area is divided into triangles and the length one side and its angles with the other two are measured, then the lengths othe other sides can be calculated


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Introduction Cont.

Purpose of Triangulation Project

The triangulation surveys are carried out

To establish accurate control for plane and geodetic surveys of large area by terrestrial methods.To establish accurate control for photogrammetric surveys of large areasTo assist in the determination of the size and shape of the earth by makinobservations for latitude, longitude and gravity.


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Introduction Cont.

Objectives of the TriangulationMain objective

Calculate spherical coordinates for four unknown points using twoknown points and angle observation.

Sub objectives

To get knowledge about the triangulation program.

To compare the accuracy between GPS observation values and thecalculated values.

To improve the collaboration with various fields and societies.

To get the experience about the management of various field.


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Introduction Cont.

The Selected FigureKataragama Peak

Karambagala

Hambantota Tower

Haburugala

Kadurupokuna

Gonadeniya

Known stations

Unknown stationsBase line


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Preliminary preparation

Organization of the projectPreparing list of requirements.Preparing schedule for observation.Preparing schedule for transportation.

Camp establishment. Instrument transferring.

GPS downloading and battery charging. Camp removal.

Preparing schedule for communication.

Organizing field assistants


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Methodology

Initial PreparationComputer Program For TriangulationSelection of Triangulation FigureInter Visibility Check In OfficeCollection of Information Required


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Results and Discussion

GPS Coordinates of Triangulation Stations

Trig StationsLatitude Longitude

D M S D M

Karambagala 06 14 17.2685333 81 00 16.5720

Kadurupokuna 06 00 54.5596600 80 46 40.7182

Gonadeniya 06 12 45.4992900 80 48 56.5211

Haburugala 06 19 49.1409600 80 57 34.3444

Kataragama peak 06 23 11.0128500 81 20 08.88718

Habantota tower 06 07 19.3904033 81 07 36.93308


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Results and Discussion Cont.

Trig Stations Latitude Longitude

D M S D M S

Karambagala 6 14 17.2683000304643 81 0 16.5716033

Gonadeniya 6 12 45.4989993551592 80 48 56.5213875

Kataragama peak 6 23 11.0140928461892 81 20 8.88699537

Hambantotatower

6 7 19.4286977848566 81 7 36.9691132

Haburugala 6 19 49.1409599999992 80 57 34.3444399

Adjusted coordinate of unknown trig stations


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Results and Discussion Cont.

Coordinate difference

Trig Stations

Coordinate Difference

Latitude Longitude

D M S D M S

Kataragama peak

0 00.107298

0 0-0.0

Gonadeniya 0 0 -0.00603 0 0 0.01

Karambagala 0 0-0.00291

0 00.0

Habantotatower

0 0-0.02902

0 0-0.0

Haburugala 0 0-0.00275

0 01.99


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Conclusions Due to the large distances between trig stations, the angular observationswere unable to taken.

The less power of PTL was also a reason for that. Any trig stations couldnot be visible from our station.Any included angle could not be subtended.

Finally, We decided to use 3 gas lamps instead of one as follows.

Therefore angle observation procedure was omitted .


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Conclusions Cont. Lot of problems had to be faced due to not completed investigation process. As result it, Angle observation procedure was omitted.

What is the alternative solution?

It is GPS observations method.

By fixing master stations as Haburugala and Kadurupokuna, GPS observationwere recorded from rover stations. The important thing is couple of GPS un(Master and Rover) should be recorded their observations within the same timduration .

Its accuracy mainly depending on the following factors.

Such as, satellite geometry, satellite availability, weather conditions etc

When increasing the GPS observation time, accuracy also increases.


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Recommendations

Observation part and investigation part were done simultaneously. So it was bettif field investigation had been done before.

It was good effort that the observation camps had done outside of the universityarea, but there must be a good pre preparation.

Powerful instruments and powerful signals.


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Websites http://en.wikipedia.org/wiki/Triangulationhttp://www.montana.edu/gps/understd.htmlhttp://en.wikipedia.org/wiki/Global_Positioning_System

Books

AGOR,R (1997)Text book of Advanced Surveying, PP.152-309.Duggal, S K. (2006) Surveying (Civil Engineering Series), PP.20-68

References And Bibliography


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Documents

Triangulation Group5