Development trend of ground digital surveying technology, existing problems and development prospect of surveying and mapping technology

With the popularization of electronic total station and computer, the mapping method of topographic map is gradually developing from traditional white paper mapping to digital mapping. Especially in the developed eastern coastal areas of China, digital mapping almost occupies most of the topographic mapping market. Engaged in digital mapping for nearly four years. Here, I will talk about my personal experience in several aspects of digital mapping, but there are bound to be endless fallacies. I hope teachers, experts and colleagues can give me some advice.

Two. working methods

At present, there are three main methods to obtain digital maps in China: digitization of original maps, aerial digital mapping and ground digital mapping. But no matter which method, its main operation flow is three steps: data acquisition, data processing and topographic map data output (printing drawings, providing floppy disks, etc. ).

1. Digitization of the original image

When a city (region) needs to use digital topographic map, but is limited by funds or time, this method is more suitable. It can make full use of the existing topographic map, only need to be equipped with a computer, digitizer, plotter and a digitizing software to carry out its work, and it can obtain digitized results in a short time. If it is difficult to implement the funds for purchasing equipment for a while, a surveying and mapping unit with the ability to digitize drawings can replace it. There are two working methods: manual tracking digitization and scanning vectorization digitization. The latter is more accurate and efficient than the former.

However, due to the influence of the accuracy of the original map and various errors in the digitization process, the accuracy of the digital map obtained by this method is worse than that of the original map. Moreover, it only reflects the various characteristics and landforms of the surface during the white paper mapping, and the current situation is not very good. Therefore, it can only be used as an emergency measure rather than a long-term solution.

In order to make full use of this method to obtain a digital map, we can measure the exact coordinates of some feature points by means of revision and supplementary measurement, and then replace the original coordinates with the coordinates of these points. Through adjustment, the accuracy of the original image can be improved to some extent. With the continuous updating of the map and the increase of measuring coordinates, the accuracy of the map will be improved accordingly.

2. Aerial digital mapping

When an area (or survey area) is very large, aerial cameras can be used to shoot ground images in the air, ground models can be established through field interpretation in the office, and digital topographic maps can be directly obtained by measuring the models with computer drawing software. With the development of surveying and mapping technology, digital photogrammetry has achieved experimental success in a certain area of China and will be popularized in the near future. It is a digital image obtained by using a digital camera in the air. In the office, the digital image is matched on the computer by special aerial survey software, and the ground digital model is established, and then the digital map is obtained by special software. It can be said that this will be an important development direction of digital mapping in the future.

The feature of this method is that a large number of field investigations can be moved indoors, and it has the advantages of fast mapping speed, high accuracy and uniformity, low cost, and is not limited by climate and season. It is especially suitable for large-scale mapping in urban dense areas. However, the initial investment of this method is large, and if an investigation area is small, its cost will be higher. So now it is basically undertaken by some relatively large units.

3. Ground digital mapping

In areas where there are no large-scale maps that meet the requirements or sufficient surveying and mapping funds, the ground digital mapping method can be directly used, also known as indoor and outdoor integrated digital mapping, which is the most widely used digital mapping method in surveying and mapping units in China. The digital map obtained by this method has the characteristics of high precision. As long as certain measures are taken, the accuracy of important features relative to adjacent control points can be controlled within 5cm. But it also consumes a lot of human, material and financial resources. In this article, I mainly talk about this experience.

Three. Selection of Surveying and Mapping Software

For a surveying and mapping unit, an important problem of digital mapping is to choose the mapping software suitable for the unit. Because the software that often works well in this unit may not be applicable in other units, each unit should analyze the problem of software selection in detail and not follow suit.

To measure the standard of a drawing software, we must first look at whether the software is suitable for the actual situation of the unit; Second, it depends on its operability, whether the interface is friendly and easy to learn; Third, it depends on whether the functions it provides are suitable for this unit.

At present, the software used by various surveying and mapping units can be described as varied and numerous. But basically, there are two kinds, one is a system (unit) developed by itself, and the other is developed by a special surveying and mapping software developer, which is provided to the majority of users for commercial purposes and is also used by various surveying and mapping units. This article refers to the latter software.

At present, there are three kinds of surveying and mapping software on the market: one is EPSW (Electronic Plane Mapping System) series jointly developed by Shanwei Company of Tsinghua and Department of Civil Engineering of Tsinghua University; Second, the RDMS series of Wuhan Reed Surveying and Mapping Automation Company; Third, CASS series and SCS series of Guangzhou south surveying and mapping Instruments Company and Guangzhou Case Company. Let's make a simple comparative analysis.

EPSW series is mainly used to measure and automatically draw various large-scale digital topographic maps, cadastral maps, pipeline maps, ground object plans, section maps, etc. , but its function is in different professional software. Its main features are as follows: 1 Real-time mapping gives full play to the advantages of the original flat-panel mapping, that is, it shows immediately after measurement, which truly realizes the integration of indoor and outdoor work in the topographic map of the delivery site; There are many detailed investigation methods; Friendly interface, easy to operate and easy to learn. The original one-step survey method can measure the root of the map, measure the broken part at the same time, and finally make adjustments.

The biggest advantage of this software is that it not only conforms to the working experience and habits of old surveyors, but also can finish the work efficiently. It should be said that it is the best electronic flat mapping system in China. Therefore, it is deeply loved by the majority of surveyors and occupies most of the electronic flat-panel surveying and mapping market. It has created a new situation of digital mapping and greatly promoted the popularization of digital mapping technology in China.

However, although the software also provides graphics zoom, windowing, moving, deleting and other functions, from the industry point of view, these functions can not meet the needs of editors in the industry. Moreover, the original work is still done in the field, which seems to violate the original intention of digital mapping to reduce field work, and the portable computers used in the field are easy to be damaged.

RDMS series is a special surveying and mapping software developed on GIS graphic platform. It also provides an electronic tablet mode. It can also transmit the measurement data stored in an electronic notebook or total station to a computer, and then make a map through interactive editing. The functions it provides are basically consistent with the original investigation habits, and it is relatively simple and easy to learn. Surveyors can be familiar with and operate quickly, provide relevant contents of cadastral survey, and handle cadastral forms conveniently and quickly. So many units engaged in cadastral survey have chosen it.

For users who are already familiar with AUTO CAD, CASS series and SCS series are a good choice, because they are developed on the platform of AUTO CAD, and all the functions of AUTO CAD can be used. AUTO CAD is a drawing platform recognized by everyone in the world, and its editing function is obvious to all.

CASS and SCS have similar functions, each with its own advantages and disadvantages. CASS's service can be said to be a phone call, while SCS's service can't be compared with it in the near future. They all provide three operation modes: electronic tablet mode, original digital mode and indoor and outdoor work integration. On the basis of CAD, many functions such as measuring fixed points, copying graphics and drawing multifunctional composite lines are developed. In addition, it also provides functions such as cadastral map drawing and drawing management. For those who want to work in electronic tablet mode and edit drawings indoors, you can choose it.

Of course, with the passage of time, the functions of these softwares will be gradually improved. My understanding of these softwares is only my humble opinion.

Four. Implementation of digital mapping field work

1. Control measurement

In digital mapping, control survey should be simpler than traditional control survey. Of course, this requirement has not changed much in the new specification, but according to my own reality,

There are some restrictions on work experience and accumulation, especially root control.

With the development of GPS technology and the popularity of total station, triangulation has basically faded out of the stage of control survey. So for most people, it undoubtedly greatly reduces the work intensity. The constraint of triangulation is removed and replaced by more flexible GPS network and traverse (network) survey. This paper only discusses graph root measurement and graph root encryption.

At present, the accuracy of electronic total station used by surveying and mapping units is generally below 6 ″ and 3+5 ppm, and it is electronic automatic reading, so the actual accuracy is higher than its nominal accuracy, which is more advantageous than optical theodolite.

As we all know, in traditional surveying and mapping, the error of the plane position of ground points is affected by the following errors:

M-spread of root propagation error of 1. graph

2. Measure the distance error m of the feature points.

3. Determine the direction error m of the feature points.

4. The pricking error of feature points on topographic map is m pricking.

5. Clear the errors caused by M painting.

To sum up, the plane position error of feature points on topographic map can be expressed by the following formula.

M thing =

Take the scale of 1: 1000 and the maximum sight distance of 100 meters as examples. According to experience, the following table can be used.

Error m propagates mm distance mm pricks mm draws mm object mm.

The value is 0.180.390.180.20 0.080.51.

However, in digital mapping, because it is automatically expanded by computer, the expansion error between the root point and the feature point of the map can be ignored and regarded as 0. Then all that remains is the m distance and the m direction. The error in the direction is limited to three times the nominal accuracy, because it is a half-measured back angle, so the error in the direction is 6x2x3 = 17 ",and the distance from the breakpoint to the station is 300m, so the m direction is = 17/206265x300 = 0.024m, and the nominal accuracy of the rangefinder is 3+5ppm. Considering the influence of various factors such as the lack of prism in the measurement, the empirical value is 0.020m, and the measurement error of the plane point relative to the graph root point is 0.032m m.

As can be seen from the above, in the case of good sight distance, due to the improvement of angle measurement and ranging accuracy of total station relative to theodolite and the application of computer, the distance of the broken point can be expanded, the root point density can be reduced accordingly, and the side length can be relaxed to 100 to 300 meters. For the sub-bureau, it is not limited by two stations. According to my practice, the accuracy of substation stations 3 to 4 can still meet the requirements. Of course, under the condition of dense urban building areas and poor visibility, the density of map root points should be increased to meet the requirements of topographic map revision or engineering lofting in the future.

2. Detail measurement

In digital mapping, the main method of detailed measurement is polar coordinate method. After the coordinates of most breakpoints are measured, the coordinates of other points can be obtained by methods such as direction intersection, distance intersection, cross-bar measurement or fixed-point measurement in the software, and the final graphics can be obtained with the help of functions such as offset, copy and extension in the software.

Small surveying and mapping units are mainly engaged in topographic map revision, construction lofting, deformation observation, municipal engineering and topographic mapping and other maintenance work. Because of the wide range and large quantity, we should simplify the staffing as much as possible, and we must create a set of methods suitable for our own units instead of adopting the operation methods of some large surveying and mapping units.

In non-electronic plane digital mapping, many units use the method of field sketch+indoor interactive editing to complete the mapping work. But in this way, it will inevitably reduce the efficiency of field work and make the operation more complicated. In the operation of surveying and mapping, sketching is not simple, especially when there are many buildings, which is quite troublesome, and it is also a waste of manpower to sketch by special personnel. The topographic mapping team of our team is basically composed of two people, one is to observe and record the code on the total station, and the other is to draw in the office. After years of practice, it is proved to be feasible.

In the coding method of dot number, generally 6-7 digits can be used, namely (0-9)(XX)(XXX), and the first digit is the connection relationship, such as 0 indicates an independent point and does not contact with other points in front; 1 is the same feature (appearance) as the previous point, which is connected with the previous point; 2 indicates a connection with a certain distance from the previous point; 3 indicates that there are three directions, and 4 indicates that the feature (appearance) ends here; 5 curve connection; Wait, the agreement between each unit and itself. The second to third digits are the codes of features (appearance), such as F2 is a two-story brick house, F0 is a simple house, FJ is a building under construction, WQ is a fence, K2 is a reinforced scarp, D 1 is an unreinforced scarp, D2 is a high-voltage line, D 1 is a transmission line, D3 is a communication line, and D 1. The last three are the points automatically increased by the total station, as shown in the figure below:

Then the point coding of each point obtained by the above coding method is as follows:

Point code remarks point code remarks

10f 300 1 brick 3 start 15 0DL0 15 class boundary start.

2 1F3002 is connected with the upper point 16 1DL0 16 is connected with the upper point.

3 1F3003 is connected with the upper point 17 1DL0 17 is connected with the upper point.

1FY004 balcony 18 4DL0 18 of brick 3 is connected with the above point.

5 0F2005 Brick 2 starts from 19 0K 10 19, and the scarp is not reinforced.

6 1F2006 is connected with the upper point; 20 1K 1020 is connected with the upper point.

7 1F2007 is connected with the upper point 2 1 3KT02 1 is connected with the upper point, with the direction of rice field.

8 0F0008 There are 22 3KT022 simple houses, which are connected with the upper point and face a paddy field.

9 1F0009 is connected with the upper point 23 4K 1023, and the scarp is not reinforced.

10 1F00 10 and the upper point are connected with 24 0K2024 to reinforce the scarp.

110d1kloc-0/1The low-voltage line starts at 25 3KT025 and is connected with the upper point, with a rice field direction.

121d1012 is connected with the upper point, with a rice field direction.

131d1kloc-0/3 and 27 4K2027 of the upper power grid reinforce the cliff.

141d1014 is connected with the above point.

By analogy, after completing the numbering (coding) of each point in the field, the points transmitted to the computer can be displayed on the computer screen in the form of spread codes when they return to the room, and then these points can be conveniently connected according to the route taken by the ruler himself, supplemented by these point codes. Or by compiling the coded boot file, automatic connection can be realized.

After this work is completed, these maps are compared with the field, and all kinds of unmeasured data in the field are measured, and then the final topographic map is obtained by interactive editing on the computer.

Of course, the use of the above methods requires higher requirements for observation and division staff. The first cooperation should be tacit understanding, which has been tested, and the next point should be to test what should be empathy; It requires the observer to skillfully input numbers and letters, which should be completed within 10 seconds (of course, some dots are not required to be input). The second division ruler is responsible for indoor drawing and is the main person in charge in the drawing process. Therefore, we should be aware of the comprehensive choice of features (appearance), determine the route of running ruler before running ruler, and try to avoid going the wrong way.

My practice shows that this method is more convenient and faster than sketching. What is needed on the station is only two processes of coding and aiming, while what the ruler needs to do is only two processes of coding and placing a prism through the intercom. At present, the total station measures a coordinate, which is basically within 1 sec, and some even reach 0.3 sec. Affected by the ruler walking, it takes about 30 seconds to measure a point, and the landform is within 1 minute. It can be said that the main time is from one point to another. In such a short time, the sketcher can't keep up with this idea and speed. I can measure about 600 to 900 points every day through my chronograph. And the connection success rate is above 95%.

For the determination of the fracture point, pay attention to the following points:

1. The building (structure) of the proportion rule only needs to measure three points, and the fourth point can be completed by computer.

2. Irregular landforms need as many measuring points as possible, because in traditional surveying and mapping, some small changes can be done by hand, but computer simulation can not truly reflect these actual landforms.

3. For blocks drawn in the order specified in the program, such as bridges and billboards. , it is best to measure in order.

In addition, the following matters should be noted:

1. The division of mapping units should be based on natural boundaries, such as rivers and roads. In order to facilitate topographic mapping and reduce boundary connection problems.

2. Try to measure the points that can be measured, and try to avoid measuring with a tape measure (steel rule). Because the speed measured by total station is far from that measured by tape measure, and the accuracy will be higher.

3. Similar features (characteristics) should be tested first to avoid unnecessary troubles caused by the industry. Of course, it can also be used flexibly according to the actual situation on site. At the same time, it is convenient for the observers on the station to input numbers and letters.

4. When measuring contour lines, in addition to measuring characteristic lines, we should also measure as many encrypted points as possible to meet the needs of computer modeling and reflect the landform more carefully.

5. Because a lot of digital mapping work is done by computer, how to strengthen the verification is solved by each unit. Especially when the measuring area is far away from the indoor location, certain measures must be taken.

As I am a preliminary exploration in this field, I still need to improve in many aspects. I hope you can give me more advice.

Development status of modern measuring instruments

Modern measuring instruments are developing in the direction of automation and digitalization, and there is a tendency to eliminate traditional optical measuring instruments (level, theodolite and flat plate). Total station is the integration of electronic theodolite and rangefinder. The total station not only has the functions of electronic meter angle measurement and electronic meter distance measurement, but also has the ability of automatic recording, storage and operation, with high working efficiency. At present, most of the new total stations introduced by various manufacturers have the following new functions: automatic focusing and aiming at the target, short distance (within 220m) without prism cooperation, operation in measurement software, large-capacity measurement data storage (more than 5000 points), menu operation (Chinese menu prompt) and so on. At present, there is also an "automatic target recognition total station", which can automatically track the reflector and get the three-dimensional coordinates in real time, and control it by comparing the software with the design value. Gyro theodolite used for high-precision orientation developed to laser gyro orientation, and gyro total station appeared through the integration of gyro and total station. GPS global positioning system has been used in large-scale first-level control survey. At present, the static GPS receiver used for control measurement has realized the integration of antenna, receiver and power supply, and its weight is only about 1kg, and its operation is completely automatic. Real-time dynamic GPS(RTK, carrier phase difference) receiver for map root control measurement and data acquisition can instantly obtain centimeter-level coordinates of ground points. In addition, it can also carry out construction lofting according to the coordinates within the range of 30~50km, and integrate the total station with GPS, thus appearing the "super station instrument". This changed the operation mode other than engineering survey, and realized the integration and seamless connection of control survey, detail survey and construction lofting. The three-dimensional laser image scanner can quickly, accurately and reliably obtain the three-dimensional spatial data of the identified object, which is very useful in bridge deformation, dam monitoring modeling, landslide monitoring, excavation capacity measurement, urban digital measurement and so on.

At present, there are still high-precision elevation measurement methods using geometric leveling, but leveling instruments have been digitized and automated. Digital level (Zeiss, Topcon, Suojia, etc. ) Not only the automatic leveling is realized, but also the automatic observation and digitization of the measurement results can be realized with the bar code ruler. Digital level mainly uses the principles of correlation method and phase method to automatically read sight distance.

With the extensive development of urban underground pipeline measurement, underground pipeline controller has also become a commonly used measuring instrument. The digital pipeline controller can not only detect underground metal pipelines, but also cement pipelines, which can not only detect the depth of lines, but also detect the depth of pipelines. Automatically record pipeline properties in and.

Most modern measuring instruments have memories for recording and storing engineering measurement data. If the measuring instrument has no memory, a universal PDA can be used to realize the integration of data recording, processing and real-time transmission. Palm computers usually do not have a standard keyboard, and input is made through a pen or a soft keyboard. Operating systems are PalmOs and WindowsCE. With the development of computer network technology and communication technology, data recording equipment can directly transmit remote data through radio, GSM or GSM mobile phones.

2 modern surveying and mapping technology

Modern surveying and mapping technology is developing towards high-tech and digitalization, among which "3S" technology is the representative of modern surveying and mapping technology. "3S" is a combination of Global Positioning System (GPS), Remote Sensing (RS) and Geographic Information System (GIS). GPS is a precise satellite navigation and positioning system developed by the United States. The system can provide high-precision three-dimensional coordinates, three-dimensional speed and time information to any user in the world around the clock. Remote sensing is a long-distance and large-area sensor for geometric shape, position and related physical characteristics. . Remote sensing in a broad sense includes aerial photogrammetry. Modern space remote sensing technology (RS) can provide image data with the resolution of 1M, and aerial remote sensing technology (DPS) can provide image data of decimeter or even centimeter level. Geographic information system is an information system that comprehensively expresses, statistically analyzes and manages geospatial information. The former two are the most advanced collection tools, which can quickly acquire data and information in real time, while the latter is the platform for data and geospatial information processing, analysis and even decision-making. Using a variety of modern advanced data communication technologies, automatic data exchange from acquisition tools to analysis management platform, from information acquisition to information processing, analysis and decision-making, and finally feedback control is realized, forming an automatic control integrated platform. "3S" integrated technology provides long-term stereoscopic monitoring capability for the earth system. It provides a tool for collecting, processing and analyzing quantitative data of earth system changes. In large-scale projects, "3S" technology is the most basic and effective tool for data and information collection, analysis and processing, and decision-making expression. It runs through all stages from survey, design, quality monitoring, safety monitoring, completion acceptance to operation monitoring and management.

In modern surveying and mapping, digital surveying and mapping is also an important surveying and mapping technology. Digital surveying and mapping is to use total station to collect data in the field and get engineering design, construction and management drawings after computer processing. This technology is widely used in urban survey and small and medium-sized engineering survey. In the past, digital mapping was generally divided into "digital recording" and "electronic tablet" mapping modes, but now it has been developed to collect data with PDA and map on the spot. Digital surveying and mapping can realize the integration of engineering survey and design and the integration and automation of data collection, update and management. Now it has become a means of GIS data collection. Another general development trend of digital surveying and mapping is the integrated application of various seed sensors such as total station, GPS receiver, digital camera and laser scanner, so as to realize the automation of large-scale mapping and the development of three-dimensional mapping, constitute three-dimensional models and three-dimensional landscapes, and serve the fields of design, planning, virtual reality and e-commerce.

3 Application of modern surveying and mapping technology in water conservancy projects

3. Application of1in large-scale water conservancy projects

In the construction of large-scale water conservancy projects such as South-to-North Water Transfer Project and Three Gorges Project, modern surveying and mapping technology has penetrated into all stages. The coordinate frame of survey and construction, that is, the establishment of control network, has been replaced by GPS positioning instead of traditional triangulation. At present, GPS positioning is developing from post-processing to real-time dynamic positioning except for large-scale (over 400km2) control survey. From simple precise positioning processing to the establishment of specific survey and construction coordinate system. In the survey stage, the digital topographic map is obtained by using all-digital photogrammetry technology and field digital mapping technology. At present, the survey has begun to transition to the integrated technology of airborne laser measurement and CCD aerial photography, in order to obtain a true three-dimensional digital map. Using digital topographic map can realize three-dimensional virtual reality, present various engineering design schemes on three-dimensional visible and measurable landscape, realize various engineering design simulations, calculate the corresponding earthwork quantity in time, and evaluate the environment of the area, thus providing the optimal design scheme.

Modern digital surveying and mapping methods are widely used in water conservancy project construction and site management. At present, in addition to a large number of total stations used for construction lofting and earthwork acceptance, and residual water meters used for measuring excavation depth and slope, there are also three-dimensional near-earth laser image scanning, GPS-RTK real-time mapping and engineering lofting, aerial photography and satellite photogrammetry, which can be used for real-time project progress management, supplemented by mobile communication and network communication to realize remote real-time monitoring. In dangerous construction such as mountain excavation and tunnel excavation, intelligent total station or GPS-GIS integrated technology can realize the automatic operation of construction machinery and the monitoring of engineering safety and quality. Intelligent total station can control the position and direction of mechanical excavation (tunnel), GPS can determine the position and attitude of construction vehicles in real time, and can realize automatic excavation control and accurate calculation of engineering quantity on site, thus realizing the automation of excavation.

After the completion of large-scale water conservancy projects, it is necessary to carry out completion surveying and mapping, and at the same time, it is necessary to provide test documents and charts during the operation of various projects. Modern surveying and mapping technology can quickly obtain these data and information, use map and DPS mapping technology to draw as-built drawings, and enter the three-dimensional visualization and networked GIS project management information system according to the requirements of digital engineering as the original basis for future project acceptance evaluation and long-term safe operation.

3.2 Application in Disaster Prevention, Mitigation and Relief

Remote sensing technology can monitor the water level of rivers and lakes in real time, and can monitor the flood area measured by the research institute in real time. The integration of RS and GIS can predict the flooded area and drought area as soon as possible, and provide accurate information for disaster prevention and relief. Remote sensing technology can not only investigate ground water resources, but also investigate groundwater resources and monitor water pollution. At present, many disaster forecasting systems (such as flood early warning information system in the lower reaches of the Yellow River) have been built in various parts and departments of China, which will play an important role in disaster prevention, resilience and relief.

3.3 Application of Deformation Monitoring

After the completion of the water control project, it is necessary to continuously and accurately monitor the reservoir dams and large bridges. Modern surveying and mapping technology provides continuous and real-time monitoring means for safety inspection and operation. If GPS, intelligent total station (measuring robot), digital vertical instrument (all automatic, all-weather, unattended) are adopted, and other industrial sensors are integrated, the fully automatic, unattended or unattended engineering operation mode can be realized. For another example, with the 3D image scanner, the millions of scanned data measured by the supervision institute can be analyzed in millimeter level, and the deformation of the whole model of the observed object can be accurately understood at any time.

3.4 Application in Water Resources Allocation

Digital topographic model (DTM) is established by digital photogrammetry or digital mapping technology, and the design work such as dam site selection, storage capacity calculation, diversion canal construction and benefit range can be carried out conveniently and quickly by applying the analysis and decision-making function of GIS, which provides scientific basis for the development and utilization of water resources. For the built reservoir, the digital model of reservoir capacity can be established by using underwater topographic survey system (real-time dynamic GPD and digital measurement and control instrument integration) and DTM. When a certain water level is known, the capacity of the warehouse can be obtained in time. Remote sensing technology can accurately provide the drought situation in a certain area. According to the storage capacity and drought, water resources should be allocated reasonably and accurately.

3.5 Application in Urban Water Supply and Drainage

The construction and management of urban underground pipelines, especially drainage pipelines, are closely related to modern surveying and mapping technology. At present, large and medium-sized cities have urban digital mapping established by digital mapping technology or all-digital photogrammetry technology. Total station and digital level have become indispensable equipment in drainage pipeline construction and urban river reconstruction. In order to avoid urban ground excavation, pipe jacking technology is increasingly used to install drainage pipes. In the construction of underground pipe jacking, the position and direction of pipe jacking can be controlled by automatic tracking total station, and an automatic guiding measurement system can be developed to realize the automation of tunneling. In order to use, maintain and manage urban underground pipelines, many cities are establishing data acquisition tools for urban underground pipeline management systems, and general GIS software (such as MAPGIS) is the main development platform. Units (such as schools and factories) can use digital mapping software to develop their own underground pipeline management system.