01-03-2011, 03:54 PM
presented by:
Punith KT
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Working and Types of Total Station
INTRODUCTION
A Total Station is a combination Electronic Transit Theodolite and Electronic Distance Measuring Device (EDM). With the aid of trigonometry, the angles and distances may be used to calculate the actual positions (x, y, and z or northing, easting and elevation) of surveyed points in absolute terms.
It is a modern surveying instrument which consists of Electronic Digital Theodolite, Electronic Distance Measuring (EDM) instrument and minicomputer are built in one unit. It automatically measures the data and transfers into computer
Total Station
The best quality total stations are capable of measuring angles to 0.5 arc-second. Inexpensive "construction grade" total stations can generally measure angles to 5 or 10 arc-seconds.
A Total Station integrates the functions of a theodolite for measuring angles, an EDM for measuring distances, digital data and a data recorder as a single unit.
Angles and distances are measured from the Total Station to points under survey, and the coordinates (X, Y, and Z or Northing, Easting And Elevation) of surveyed points relative to the total station position are calculated using trigonometry and triangulation.
Components of a Total Station
Electronic Distance Measuring (EDM)
Transit Electronic Theodolite
On-Board Micro-processor
Data Collector (Built in or separate unit)
Data Storage (Internal or memory card)
Prisms
Tripod and Pole
Features of Total Station
EDM is fitted inside the telescope,
Digital display,
Compatibility with computers,
Measures distance and angles and displays coordinates,
Auto level compensator is available,
Can work in lesser visibility also,
Can measure distances even without prismatic target for lesser distances,
It is water proof
A Laser Optical Peewit for exact centering.
Display or circular vial and plate bubble in the both direction for easy leveling.
Accurate dual axis compactor using which the instrument can level ever on uneven ground.
The telescope length is short hence comfort and easy to sight.
Additional Features
New Total Stations have atmospheric correction, and auto-focus. In addition, these series incorporates a quick distance measuring mode and a high data storage capacity for increased productivity.
The new Total station gives the unique opportunity for long range distance monitoring of up to 9000m to a single prism
The Electronic field book can be store up to 10,000 data points .
Data can be downloaded from the Total Station to a computer and application software used to compute results and generate a map of the surveyed area.
How Does Total Station Work . . ?
A standard Transit is basically a Telescope with cross-hairs for sighting a target;
The telescope is attached to scales for measuring the angle of rotation of the telescope (normally relative to north as 0 degrees) and the angle of inclination of the telescope (relative to the horizontal as 0 degrees).
After rotating the telescope to aim at a target, one may read the angle of rotation and the angle of inclination from a scale.
The electronic transit provides a digital read-out of those angles instead of a scale;
It is both more accurate and less prone to errors arising from interpolating between marks on the scale or from mis-recording. The readout is also continuous; so angles can be checked at any time.
