Which button to press for vertical angle of edj2-cl theodolite?

Chinese name: theodolite English name: theodolite; transit Definition 1: A surveying and mapping instrument that measures horizontal and vertical angles. Applied disciplines: Surveying and mapping (first-level subject); Surveying and mapping instruments (second-level subject) Definition 2: Instruments for measuring horizontal and vertical angles and orientations. Applied disciplines: Mechanical Engineering (first-level subject); Optical instruments (second-level subject); Geodetic surveying instruments - theodolite (third-level subject) Definition 3: Instruments for measuring horizontal angles, vertical angles and measuring distances in conjunction with the stadia. Applied disciplines: water conservancy science and technology (first-level subject); water conservancy survey and engineering geology (second-level subject); water conservancy engineering surveying (third-level subject). The above content is approved and published by the National Scientific and Technological Terminology Approval Committee. For help, edit encyclopedia business card theodolite, measuring horizontal angles and vertical angle instruments. It is designed based on the angle measurement principle. The most commonly used one at present is the optical theodolite. Catalog Structure Classification Purpose and working principle Homemade method Edit this section Structure of theodolite Structure Machine components 1. The structure of theodolite (main common components): Theodolite 1 Telescope brake screw 2 Telescope 3 Telescope micro-motion spiral 4 Horizontal brake 5 Horizontal micro-motion spiral 6 Foot screw 9 Optical sight 10 Objective lens focusing 11 Eyepiece focusing 12 Dial reading microscope focusing 13 Vertical plate indicator tube level micro-moving screw 14 Optical plummet 15 Base circular level 16 Instrument base 17 Vertical Dial 18 Vertical dial illumination mirror 19 Sighting part tube level 20 Horizontal dial position change hand wheel The telescope is fixedly connected to the vertical plate and installed on the bracket of the instrument. This part is called the sighting part of the instrument and belongs to the instrument. upper part. The telescope together with the vertical plate can rotate in the vertical plane around the horizontal axis. The collimation axis of the telescope should be orthogonal to the horizontal axis, and the horizontal axis should pass through the center of the water plate. The digital axis of the collimation part (the rotation axis of the collimation part) is inserted into the sleeve of the instrument base, and the collimation part can rotate horizontally. Edit this paragraph classification Theodolite is divided into vernier theodolite, optical theodolite and electronic theodolite according to the different dial scale and reading method. At present, our country mainly uses optical theodolite and electronic theodolite, and the vernier theodolite has long been eliminated. Electronic theodolite optical theodolite optical theodolite The horizontal and vertical dials of the electronic theodolite optical theodolite are made of glass. There are equally spaced theodolite lines engraved on the periphery of the dial plane. The distance between two adjacent lines is equal to The central angle of the pair is called the grid value of the dial, also known as the minimum division value of the dial. Generally, the accuracy is determined by the size of the grid value, which is divided into: DJ6 dial grid value is 1° DJ2 dial grid value is 20′ DJ1 (T3) dial grid value is 4′ According to the accuracy from high precision to low precision: DJ07 , DJ1, DJ2, DJ6, DJ30, etc. (D and J are the initials of geodetic and theodolite respectively) Theodolite is a precision measuring instrument used to measure angles in survey tasks. It can be used for measuring angles, engineering stakeout and rough distance measurement. . The entire set of instruments consists of two parts: the instrument and the tripod. Application example (the coordinates of two points A and B are known, and the coordinates of point C are found): The instrument is set up at one of the two points A and B with known coordinates (the instrument is set up at point A as the column), and the placement alignment is completed. After the basic operation in , aim at another known point (point B), then configure a reading 1 according to your own needs and record it, then aim at point C (unknown point) and read reading 2 again. The difference between reading 2 and reading 1 is the angle value of angle BAC. By accurately measuring the distance between AC and BC, the precise coordinates of point C can be calculated mathematically. On some construction project sites, we often see technicians carrying out measurements with an instrument. The instrument they use is a theodolite. The initial invention of the theodolite was closely related to navigation. In the fifteenth and sixteenth centuries, some developed countries such as Britain and France needed to draw various maps and charts due to navigation and war. The earliest method of drawing maps was triangulation, which is to find the position of a third distant point based on the observation results at two known points. However, due to the lack of suitable instruments, the angle measurement methods were limited and the accuracy was not high. The topographic map produced is also not very accurate. The invention of the theodolite improved the accuracy of angle observation, simplified the process of measurement and calculation, and provided more accurate data for drawing maps. Later, theodolite was widely used in the measurement of various engineering constructions. Theodolite consists of three parts: base, dial (horizontal dial and vertical dial) and sighting part. The base is used to support the entire instrument. A level dial is used to measure horizontal angles. There are telescopes, level tubes, reading devices, etc. on the sighting part. Edit this paragraph Purpose and working principle Theodolite is the main angle measuring instrument in surveying work. It consists of telescope, horizontal dial, vertical dial, level, base, etc. When measuring, place the theodolite on a tripod, use a plumb ball or optical plummet to align the center of the instrument with the ground station, use a level theodolite to level the instrument, use a telescope to aim at the measurement target, and use a horizontal dial and a vertical dial. Measure horizontal and vertical angles. According to the accuracy, it can be divided into precision theodolite and ordinary theodolite; according to the reading equipment, it can be divided into optical theodolite and vernier theodolite; according to the axis system structure, it can be divided into re-measurement theodolite and directional theodolite.

In addition, there are coded dial theodolite that can automatically record dial readings according to coded holes; automatic tracking theodolite that can continuously and automatically aim at air targets; gyrotheodolite and laser theodolite that use the principle of gyro orientation to quickly and independently determine the orientation of ground points; with theodolite, meridian An all-purpose theodolite for astronomical observation with three functions of a celestial instrument and a zenith instrument; a photographic theodolite that combines a camera and theodolite for ground photogrammetry, etc. An instrument for measuring horizontal and vertical angles. It was first developed by the British machinist Sisson in about 1730. It was later improved and formally used in British geodetic surveying. In 1904, Germany began to produce glass dial theodolite. With the development of electronic technology, electronic theodolite appeared in the 1960s. On this basis, electronic speed testers were developed in the 1970s. A theodolite is the mechanical part of a telescope that allows the telescope to point in different directions. The theodolite has two mutually perpendicular axes to adjust the azimuth and horizontal height of the telescope. This type of stand has a simple structure and low cost. It is mainly used with ground telescopes (for geodesy, bird watching, etc.). If it is used to observe celestial bodies, since the diurnal movement direction of celestial bodies is usually not perpendicular or parallel to the horizon, it needs to be rotated at the same time. Only by changing the rotation speed of two axes over time can you track celestial objects. However, other celestial objects in the field of view will rotate relative to the target celestial object. Unless a mechanism is added to offset the rotation of the field of view, it is not suitable for long-exposure astrophotography. Edit this paragraph to make your own method

1. Right ascension and declination In the vast sea, when a sailing ship encounters danger and seeks first aid, the first thing is to let the rescuers know the location of the ship, and also This means informing the rescuers of the latitude and longitude of the ship. Latitude and longitude do more than just point out a ship's location on the ocean. Its biggest advantage is that it can make the exact position of an object simple and clear to everyone. Similarly, once a new star is discovered in the endless sea of ??stars in the night sky, how do you make its correct position known to the world? Have you ever thought that there should be a measurement system similar to latitude and longitude to calibrate the position of the planet and make star maps? The measurement systems used by astronomers are Right Ascension and Declination. The units of Declination are Degrees, and the units of Right Ascension are Hours and Minutes. We may not understand these. Familiar, but not difficult to understand. Because the stars are so far away from us that we cannot tell the difference between them with our eyes alone, these planets all appear to be equally far away from us. We imagine that there is a suspended spherical shell covering the entire earth. This imaginary ball is called the celestial sphere, and these stars are fixed on the inside of the spherical shell. We can only see half of the sphere at a time. Because of the rotation of the earth, the celestial sphere seems to be constantly rotating around us from east to west. The north (south) pole of the celestial sphere is directly above the geographical north (south) pole of the earth, and the celestial equator is also directly above the earth's equator. , ascended the throne in the center of the two celestial poles. Like the earth, we mark the celestial sphere with latitude and longitude. In astronomy, this is equivalent to the latitude (longitude) of the earth, which is called declination (right ascension). From the celestial pole to the celestial equator, the declination is 90°; the right ascension is 24 hours, and 1 hour is 60 minutes, that is, 1h=60m=15°. This is because the earth or celestial sphere rotates every hour. It is named after 15°. This method of determining the position of celestial bodies seems quite complicated, but it has many advantages. For example, the celestial sphere is constantly rotating, so the apparent positions of stars are constantly changing, such as crossing the night sky from east to west. At the same time, due to the revolution of the earth, even at the same moment, a few days later, the positions of stars are slightly westward; or As you walk from north to south, the relative positions of the stars to the horizon also change. Since the apparent positions of stars are so fickle, it is quite difficult to explain their positions based on what we see. We can only explain them through right ascension and declination, because each planet corresponds to a set of right ascension and latitude. . But since the stars change rapidly, how should we measure their right ascension and declination? 2. Production of theodolite Theodolite is used to measure right ascension and declination. It is an observation device with many characteristics of an astronomical telescope. Now we will introduce a simple theodolite method. The required materials are listed in Table 1. The size of each material is for reference only and can be modified at your own discretion, but the relative position of each part must be clarified. Before making, take a look at Figure 1, Figure 2, Figure 3, and how to do it: 1. Use a three-quarter plywood with a thickness of (3/8), and saw off two discs with a diameter slightly smaller than the protractor (protractor) (1/2 )". Use strong glue to glue two protractors on each disc. The midpoint of the bottom edge of the protractor must be firmly glued to the center of the disc. (See Figure 2). 2. Fix a disk on D with two screws. The line connecting the center of the disk and 90° must overlap with the center line of D. Screw a screw ring on each end of D (note that they are not screwed) On the side with the disk (see Figure 2), the line of sight can be observed through two small circles. 3. In the center of the other disk, drill a (1/4)" hole. This hole should pass through A and C at the same time (see Figure 3). Pass a screw through it and tighten it. Adjust the tightness. Make C easy to rotate. 4. Drill a hole from the center of the protractor attached to D, and tighten D and C with wooden pegs or screws, but D and C should be able to rotate and not fixed.

5. Cut out three triangles with iron sheets and attach them to C with screws or small nails. The tips of the triangles must be flat against the protractor. 6. Connect A and B with hinges. (See Figure 1) 7. Drill a small hole (3/4)" from one end on G and H. Starting 1" from this hole, drill a width (3/16)" along the center line of each wooden tape. Make a small slit until it is 1" from the other end. Use screws to bolt G and H to the two sides of A in the small hole, and then use a drill to bolt G and H to the sides of B through the thin slit. This is used to adjust the angle x. When driving screws or seat drills, they should be nailed in the proper position so that A and B can overlap when adjusted to the end of the slit. The theodolite is now ready for use. 3. Use of theodolite: Support the theodolite on a stand, such as a chair or a camera tripod. The purpose is only to make it easy to observe through the screw circle of D. Place the theodolite facing the south. First, do not raise the viewing arm D (that is, the latitude table E points to zero). Adjust the tilt of the B plate so that the line of sight can see the horizon along the viewing arm. Fix the B plate in this position. At this time Panel B remains horizontal. Now rotate C and D to observe the celestial body. Then E indicates the altitude of the celestial body. Now raise plate A of the theodolite to angle x, x=90° - (the latitude of the measured place). For example, if you measure in Taipei, the latitude is about 25°3', the angle x is equal to 64°57'; another method Point the viewing arm to Polaris, keep D in this direction, and move plate A so that the reading of latitude table E is 90°. At this time, plate A is at an x ??angle with B. Of course, you will know after a little thought that you can use this There is no way to measure the latitude of your location. Why do A and B form an x ??angle? (Note 1) When looking up at the celestial pole (i.e. at the North Star), the elevation angle is your latitude. Therefore, when the E reading is zero, after lifting plate A at an x ??angle, the viewing arm points to the celestial equator. Why? (Note 2) The purpose of adjusting the x angle is to find the elevation angle of the stars to the celestial equatorial plane (that is, the declination), without taking into account the changes in the apparent positions of the stars caused by the different latitudes of the observation site. At this time, by rotating the viewing arm from west to east, the position of the celestial equator is drawn. In order to measure right ascension, you must mark the longitude table F into right ascension units - hours, every 15° as 1 hour, starting from zero and marking counterclockwise. Now move the sight arm to gaze at a known star in the southern sky. Determine the right ascension and declination of the star from star charts, astronomical calendars or other reference star sources. Rotate the longitude table F so that the pointer of C points to the appropriate right ascension value. At this time, the latitude meter should automatically point to the correct declination value, otherwise the instrument will be biased. Fix F, now rotate C and D, and point the sight arm to another planet. At this time, you can read the declination and right ascension of this planet from E and F. The declination of a star north of the celestial equator is positive, and the declination of a star south of the celestial equator is negative. That is, the protractor degree toward the opening on the E disk is positive, and the other is negative. For example: Spica is visible in the night sky in April, May and June. Its right ascension (R.A.) = 13h23m37s, declination (D.) = -11°00'19'', and the apparent arm Point to the star Spica. At this time, the latitude meter E should read about -11°. Adjust the longitude meter F to 13h23m37s. Now rotate the visual arm D and look at Regulus. At this time, you can read about 12°06' on E and about 10h07m on F. So we know that R.A.=10h07m and D.=12°06' of Regulus. . For another example, Sirius is visible in the winter night sky. R.A. is about 6h44m, and D. is about -16°40'. After adjusting F to 6h44m, raise the visual arm to about 25° declination, and then head west Rotate until the right ascension is about 3h45m. At this time, through the screw circle on D, you can see the Pleiades. Early in the autumn and winter nights, a hazy bright band can be seen near the Great Square of Pegasus. It is the Andromeda Nebula. It is the only one among the spiral nebulae that can be clearly seen by the naked eye. Are you interested? Can I ask for its approximate location? Approximately R.A.=0h40m, D.=41°. The advantage of using this method to determine right ascension and declination is that you don’t have to worry about the factors that cause changes in the apparent position of the planet due to different observation times. Why? Because plate A coincides with the celestial equatorial plane after being corrected by the x angle, what E obtains is the elevation angle of the star to plate A (that is, the celestial equatorial plane), which is naturally the declination. In addition, although the celestial sphere is constantly rotating, almost all the stars are extremely distant stars, and their relative positions do not change. We know the right ascension of one star, and based on this, we can naturally determine the distance between this star and other stars. angle, and find the right ascension of another star, so no matter what latitude, season, or time you observe, there will be no difference in the right ascension and declination of the star you find. Some reference star sources are listed in Table 2. The devices required for many great experiments are often quite simple, so don't underestimate the theodolite. It is very likely that one day you will use it to calibrate the position of a planet that has never been discovered by anyone, and become famous all over the world. ? The original text is excerpted from "Challenge of the Universe", page 117, "Projects and Experiments" published by "National Science Teachers Association" in 1962.

The original text only explains the production method and does not discuss the principles. The translator has added some simple explanations of the principles. Note 1: See Figure 4. Panel B points to the southern horizon, D points to the celestial north pole, and panel A is perpendicular to D. ∠Y is the latitude of the place of observation. Because the North Star is far away from the earth, D points to the celestial north pole, which is the same as the North Pole to the earth. The lines connecting the hearts are parallel, and we can easily prove that ∠Z=∠Y, and ∠x+∠Z=90°, so ∠x=90°-∠Z=90°-∠Y=90°-(observation latitude of the earth). Note 2: When the E reading is zero, D is parallel to A. As shown in Figure 4, A is at right angles to the celestial north pole, which means it points to the celestial equator, so D also points to the celestial equator. Principle Theodolite is designed based on the principle of angle measurement. In order to measure the horizontal angle, a disc with angular divisions - a horizontal dial - must be placed horizontally on the vertical line passing through the intersection of the two directional lines in space (Figure 2). In the figure, the intersection of the vertical plane of OAA1 and the horizontal dial gets the reading ɑ on the dial, the intersection of the vertical plane of OBB1 and the horizontal dial gets the reading b on the dial, b minus ɑ is the central angle β, that is is the angle value β1 of the horizontal angle A1O1B1. In order to measure the vertical angle, a disc must be placed vertically - a vertical dial. Since one direction of the vertical angle is a specific direction (horizontal direction or zenith direction), the vertical angle value can be obtained by simply reading the reading on the vertical dial when the line of sight is pointed at the target to be measured. Category There are many types of theodolite, which can be divided into ordinary theodolite and precision theodolite according to their accuracy. There are certain series of standards. The precision optical theodolite produced in China has a measurement error of no more than ±0.7″ in the horizontal direction. Its telescope magnification is 56 times, 45 times, and 30 times. The diameter of the horizontal dial is 158 mm. The minimum reading value is 0.2″. The vertical degree The disk diameter is 88 mm, and the minimum reading value is 0.4″. Theodolite is divided into vernier theodolite, optical theodolite and electronic theodolite according to the reading device; according to the axis system, it can be divided into re-measurement theodolite and directional theodolite. At present, the most commonly used is the optical theodolite. In order to use The operation is convenient and the efficiency is improved. This type of instrument has some improvements on the original basis, such as using an erect telescope; a fast focusing and slow focusing mechanism; a coaxial braking and micro-movement mechanism; the dial reading is digitized, and the instrument is equipped with a digital instrument. A reading microscope with a graticule or a reading microscope with an optical micrometer; the two dial images appear in different colors; there are coarse and fine configuration dial mechanisms and automatic zeroing devices for vertical dial indicators; there are also some with special functions. Theodolite, for example, a sight-range theodolite with an optical distance measuring device; a compass theodolite that uses a magnetic needle to determine the magnetic north position; a gyro theodolite that combines a gyroscope and a theodolite to determine the true north position (see mine survey); uses a laser to form Visible collimation axis, laser theodolite for guidance, positioning and collimation measurement; photographic theodolite for ground photography; film theodolite for automatic tracking and measurement; electronic theodolite for automatic angle measurement and recording; and electronic theodolite and electromagnetic wave distance measuring device. , micro information processor and recorder are integrated into a single electronic speed measuring instrument. The electronic speed measuring instrument can not only quickly obtain slope distance, horizontal distance, height difference (or elevation) and coordinate increment (or coordinates) on site. ) and other data, and can automatically display, print and punch records, or store data on tape, and can also create digital terrain models, or use a special interface to connect to a computer to automatically generate maps when working in dark environments such as tunnel projects. , the visible laser beam emitted by the LDT520 can efficiently implement direction control and point positioning in a cloudy environment, and the effective operating radius of the laser beam is up to 600m, and further in a dark environment.