DIFFERENT FUNCTION OF TOTAL STATION SOKKIA CX-105/CX-60,LEICA TS09PLUS,TOPCON GT SERIES,HEXAGON
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- เผยแพร่เมื่อ 6 มี.ค. 2018
- 1. Introduction
The Total station is designed for measuring of slant distances, horizontal and vertical angles and elevations in topographic and geodetic works, tachometric surveys, as well as for solution of application geodetic tasks. The measurement results can be recorded into the internal memory and transferred to a personal computer interface.
The basic properties are unsurpassed range, speed and accuracy of measurements. Total stations are developed in view of the maximal convenience of work of the user. High-efficiency electronic tachometers are intended for the decision
It has the broad audience for sole of industrial problems.
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.
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.
A total station is an electronic/optical instrument used in modern surveying. It is also used by archaeologists to record excavations as well as by police, crime scene investigators, private accident Reconstructionists and insurance companies to take measurements of scenes. The total station is an electronic theodolite (transit) integrated with an electronic distance meter (EDM), plus internal data storage and/or external data collector.
The purpose of any survey is to prepare maps, control points formed a basic requirement for the preparation of these maps.
There are several numbers of methods like traverse, triangulation etc., to provide these control points.
Whatever the method the provision of control points, includes the measurement of two entities( Distance and Angle).
Again, distance can be measured by using various instruments like chain, tape.
Linear Tap.
Gunter’s chain (20m and 30m).
Steel band(20m and 30m).
Inver tap.
Hunter Short Base (80m).
Electronic Distance Measurement Instruments, Total station and GPS.
Angle can be measured by using a THEODOLITE.
Once distance and angular measurement is over computation is performed to provide the control points. A combination of all the three results in a powerful instrument called TOTAL STATION.Hence, the TOTAL STATION is an instrument which consists of the following:
i) Distance measuring instrument (EDM).
ii) An angle measuring instrument (Theodolite).
iii) A simple microprocessor.
1.2. Instrumentation:
It consists of an EDM, Theodolite, Microprocessor combined into one. It also has a memory card to store the data. It also consists of battery socket which houses the battery. A fully charged battery works for about 3 to 5 hrs continuously.
DifferentPartsofTS
Figure 1: Different Parts of Total Station
1.3. Accuracy of a Total Station:
Accuracy depending upon the instrument and varies from instrument to instrument
1.The angular accuracy varies from1″ to 20 ″.
2.Distance accuracy depends upon two factors.
Instrumental error which ranges from
+ / - 10mm to + / - 2mm.
b) Error due to the length of measurement.
It can be from + / - 10mm to + / - 2mm per kilometre.
1 prism, 2.5-2.7 km2 prisms
5-7 km3 prisms
10-12 kmNIKONOne second+ / - 2mm/km or 2ppmTriple the number of prisms double the distance.LEICAOne second SOKKIAOne second.
1.3.1. Accuracy & Precision
• Precision is the reproducibility of the measurement.
• Accuracy is how close the measured position is to the actual location
Measurement of distance is accomplished with a modulated microwave or infrared carrier signal, generated by a small solid-state emitter within the instrument’s optical path, and reflected by a prism reflector or the object under survey. The modulation pattern in the returning signal is read and interpreted by the onboard computer in the total station. The distance is determined by emitting and receiving multiple frequencies, and determining the integer number of wavelengths to the target for each frequency. Most total stations use purpose-built glass Porro prism reflectors for the EDM signal, and can measure distances to a few kilometers. Reflectorless total stations can measure distances to any object that is reasonably light in color, to a few hundred meters.
Principle:
Given the co-ordinate of the instrument position and bearing of a backward station the c