What are the measuring instruments for knowledge e

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Engineering surveying instruments are all kinds of instruments for orientation, distance measurement, angle measurement, height measurement, mapping and photogrammetry required for surveying work in the planning, design, construction and operation management stages of engineering construction. Theodolite is an instrument for measuring horizontal angle and vertical right angle, and level is an instrument for measuring the height difference between two points

flat panel instrument is the main instrument for manually mapping large-scale topographic map on the ground. Electromagnetic wave rangefinder an instrument that measures the distance between two points by using electromagnetic wave to carry the ranging signal. The following editor will introduce the relevant knowledge of engineering measurement instruments

what are the common methods and instruments of engineering measurement

I. elevation survey

elevation survey mainly includes leveling and trigonometric leveling

leveling is to use the horizontal line of sight to measure the height difference between two points. Because of the high accuracy of leveling, it is the most important method in height measurement

trigonometric leveling is to measure the horizontal distance or oblique distance and vertical right angle (i.e. inclination angle) between two points, and then use trigonometric formula to calculate the height difference between two points. The accuracy of trigonometric leveling is generally low, and it is only adopted under appropriate conditions

the following mainly introduces the basic methods and instruments of leveling

1. Basic method of leveling

2 Level introduction

micro tilt level is widely used in general leveling. DS3 micro tilt level consists of the following three main parts:

telescope - it can provide line of sight and read the readings on the distant level

level - used to indicate whether the instrument or line of sight is in a horizontal position

base - used to level the instrument. It supports the upper part of the instrument and can turn the upper part of the instrument in the horizontal direction

automatic leveling level

1. principle &mdash& mdash; A compensator is added to the optical path of the telescope

2. Use &mdash& mdash; After rough leveling, the observation warning indicator windows in the telescope should all be green; The best state is the triangular spire and horizontal index line of the indicator window

3. Calibration &mdash& mdash; A compensator inspection should be added, that is, rotate the foot screw to destroy the rough level, and see whether the warning indicator window appears red

electronic level

the level ruler used with the electronic level is a bar code ruler, which is usually made of glass fiber or indium steel. The electronic level is equipped with a row array sensor, which can recognize the bar code on the level staff. After the electronic level takes in the bar code, it is converted into the corresponding number by the processor. After signal conversion and digitization, the middle wire reading and sight distance are directly displayed on the display screen

II. Angle measurement

the instruments for angle measurement are mainly theodolites, which are divided into optical theodolites and electronic theodolites

optical theodolites

the horizontal and vertical dial of optical theodolites are made of glass, and equally spaced dividing lines are engraved on the peripheral edges of the dial plane. The central angle of the circle opposite the spacing of two adjacent dividing lines is called the grid value of the dial, also known as the minimum grid value of the dial. Generally, the accuracy is determined by the size of the grid value, which is divided into:

DJ6 degrees, and the grid value is 1° DJ2 grid value is 20 'DJ1 (T3) grid value is 4'

according to the accuracy from high accuracy to low accuracy: dj07, DJ1, DJ2, DJ6, dj30, etc. (D, J are the initials of the earth and theodolite respectively)

electronic theodolite

Introduction to the principle of electronic angle measurement

electronic angle measurement is still carried out by using the dial. Different from optical angle measurement, electronic angle measurement is to obtain the electrical signal from the dial in a special format, convert it into an angle according to the electrical signal, and automatically output it in digital form, display it on the electronic display screen, and record it in the memory. According to different ways of obtaining electrical signals, electronic angle measuring disc can be divided into grating angle measuring disc, coding angle measuring disc and electric grating angle measuring disc

sojia electronic theodolite

Southern electronic theodolite

III. distance measurement

distance measurement is divided into steel ruler measurement, sight distance measurement and photoelectric ranging

1. Steel ruler measurement

where: n— Number of full length segments; l— Length of steel ruler (m); q— Surplus length less than one full foot (m)

2. Sight distance measurement

theodolite sight distance measurement is a traditional indirect measurement method of horizontal distance and height difference. Tools used: theodolite and sight gauge

3 Photoelectric ranging

IV. coordinate measurement

one of the main tasks of engineering measurement is to measure or set out the three-dimensional coordinates of spatial points. The instruments used mainly include total station and GPS receiver

total station

main features of total station (Continued)

automatic display of horizontal angle, vertical angle and oblique distance, and automatic calculation of mirror station coordinates, elevation, horizontal distance and other data

there are various ways of data recording and storage: memory, PCMCIA card, serial port communication

automatically compensate the horizontal angle and vertical angle

meteorological correction and instrument constant correction for distance

provide electronic bubbles in digital or graphic form for leveling

laser point aligner

basic steps of coordinate measurement

(1) set the three-dimensional coordinates of the survey site

(2) set the coordinates of the rear view point or set the horizontal dial reading of the rear view direction as its azimuth. When setting the coordinates of the backsight point, the total station will automatically calculate the azimuth of the backsight direction and set the reading of the horizontal dial of the backsight direction as its azimuth

(3) set the prism constant

(4) set atmospheric correction value or air temperature and pressure value

(5) measure the instrument height and prism height and input them into the total station

(6) aim at the target prism, press the coordinate measurement key, and the total station will start ranging and calculate the three-dimensional coordinates of the displayed measuring points

introduction to all kinds of total stations

longer range: distance measurement without prism reaches 400m

faster ranging speed: the ranging speed is measured to be twice faster than that of similar products

longer battery life: advanced power management system, saving more than 30% power

more convenient humanized design: SD card storage function, automatic temperature and pressure sensor

better waterproof performance: waterproof grade IP55

SET220K . SET320K . SET520K . Set6120k set10k series total station has the characteristics of light body and complete functions. The backlit full numeric keyboard makes the operation more convenient. It is widely used in all kinds of engineering and measurement work? Double sided backlit full digital keyboard makes data input more convenient (set620k is a single-sided keyboard).? General efficient measurement software, IP66 high-grade dust-proof and waterproof performance. Application of setting out survey, road calculation and setting out, alignment survey, concrete component assembly and positioning, construction engineering control, area calculation, deformation monitoring

GPS receiver

terrestrial GPS

geodesic receiver is mainly used for precision geodesy and precision engineering measurement. This kind of instrument mainly uses the carrier phase observation value for relative positioning, and the positioning accuracy is high. The structure of the instrument is complex and the price is expensive. According to the use and accuracy, it is divided into static (single frequency) receiver and dynamic (dual frequency) receiver, namely rtk

at present, in terms of GPS technology development and practical application, internationally renowned manufacturers include Trimble navigation company of the United States, Leica Geosystems of Switzerland, TOPCON of Japan, and domestic manufacturers mainly include Nanfang surveying and mapping, zhonghaida, chinasurvey, Kelida, etc

through the above introduction, I also have a good understanding of the engineering measurement instruments. Thank you for stopping your precious time to enjoy the article edited by Xiaobian. If you want to learn more about relevant knowledge, please continue to pay attention to Qijia information




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