AU2021294070B2

AU2021294070B2 - Method for smart high-precision positioning of excavator based on satellite navigation

Info

Publication number: AU2021294070B2
Application number: AU2021294070A
Authority: AU
Inventors: Suzhong DU; Zhigao WEI; Guopeng YI; Lubin Zhang; Yupeng Zhang; Bihui ZHOU
Original assignee: WANBAO MINING Ltd
Current assignee: WANBAO MINING Ltd
Priority date: 2020-06-18
Filing date: 2021-04-16
Publication date: 2023-01-05
Anticipated expiration: 2041-04-16
Also published as: WO2021253958A1; AU2021294070A1

Abstract

A method for the smart high-precision positioning of an excavator (1) based on satellite navigation, relating to the field of the comprehensive application of satellite technology. In order to overcome the problem of being unable to implement automatic and smart high-precision positioning of an excavator (1), a transceiver (2), a measurement antenna, a single-axis angle sensor, a dual-axis angle sensor, and a vehicle-mounted computer (5) are mounted on the excavator (1) and, by means of Beidou high-precision spatial information technology and an analysis algorithm, the precise position of the excavator (1) and the main components thereof can be solved; by means of constructing side view and top view two-dimensional coordinates, the relative coordinates of each point in the operating attitude of the excavator (1) are rationally analysed and solved, and the coordinate system is converted to implement precise positioning of each main component. On the basis of precise positioning, the present invention can implement rapid positioning, increase positioning precision, and implement automatic guidance and tracking of the excavator, meeting the needs of different industrial engineering applications.

Description

METHOD FOR SMART HIGH-PRECISION POSITIONING OF EXCAVATOR BASED ON SATELLITE NAVIGATION

TECHNICAL FIELD The invention relates to the field of comprehensive application of satellite technology, and particularly to an method for the smart high-precision positioning of excavator based on satellite navigation.

BACKGROUNDART High-precision positioning, navigation and timing services based on Global Navigation Satellite System (GNSS) have been widely used in agriculture, transportation, energy, power and other sectors of the national economy, wherein a coordinate system is the basis of defining positioning: Space rectangular coordinate system: the coordinate origin is located at the center of the reference ellipsoid, the Z axis points to the north pole of the reference ellipsoid, the X axis points to the intersection point of the starting meridian plane and the equator, the Y axis is located on the equatorial plane and forms an angle of 90 degrees with the X axis according to the right hand system, and the coordinates of a certain point can be defined by the projection of the said point on each coordinate axis of the coordinate system. Geodetic coordinate system: geodetic latitude, longitude, and absolute elevation are used to define spatial locations. Latitude is the angle between the normal line of a spatial point and the reference ellipsoid and the equatorial plane; longitude is the angle between the plane of a spatial point and the reference ellipsoid's rotation axis and the starting meridian plane of the reference ellipsoid; and absolute elevation is the distance from a spatial point to the reference ellipse along the direction of the normal of the ellipsoid. Gauss plane rectangular coordinate system: for the convenience of work, the area to be measured needs to projected onto the plane to make the measurement, calculation and drawing easier. When the area to be measured is large and the accuracy requirement is high, the influence of the earth curvature on the plane coordinate system cannot be ignored. The conversion of the points on the earth to a plane is called map projection. Gauss projection is commonly used in China, that is, the earth is divided into zones according to the meridian, which are called the projection zones; and the projection starts from the first meridian, which is divided into two types: a 6° zone and a 3 zone. A zone divided at the interval of 6° is called a 6° zone, and a zone divided at the interval of 3 is called a 30 zone. Through Gauss projection, the projection of the central meridian is taken as the ordinate axis represented by x, the projection of the equator is taken as the abscissa axis represented by y, and the intersection point of the two axes is taken as a coordinate origin, thus forming a plane rectangular coordinate system called the Gauss plane rectangular coordinate system. Independent coordinate system: a rectangular coordinate system is selected for the origin and the coordinate axis according to the local operation requirements and coordinate definitions. Relative to the unified national coordinate system, it is a local plane or rectangular coordinate system independent of the national coordinate system. In general, the X axis indicates the north, the Y axis indicates the east, and the elevation is defined by selecting a local datum value. The independent coordinate system, the Gauss plane rectangular coordinate system and other coordinate systems can be converted into one another. As a mechanical apparatus, excavators are widely used in various fields of national economy. An excavator is composed of a power unit, working devices, a slewing mechanism, a control mechanism, a transmission mechanism, a walking mechanism and auxiliary facilities, wherein the walking mechanism includes a chassis (bottom plate) based on tires or tracks, and the working devices include a big arm, a small arm, a bucket and auxiliary devices. High-precision guidance, command and monitoring can be realized by positioning the excavator walking mechanism and the working devices with high precision, which can improve the operation efficiency of the excavator, optimize its operation effect and reduce the loss during its operation. For example, when a project is under construction, damages to surrounding objects can be avoided, precise operation can be conducted in invisible areas such as underwater and caves, loss and depletion can be reduced in mining, and economic benefits are considerable. The conventional positioning guidance, command and monitoring are mainly carried out manually: the measurers are required to set out a datum line and drive piles in advance during the guidance; the experience and attitude of on-site commanders and excavator operators are mainly relied on during command and monitoring, and the accuracy usually does not meet the requirements. The automatic and smart high-precision positioning of excavators is the basis of guiding, monitoring and unmanned operation of excavators, which is of great significance to different industries. In terms of high-precision positioning in excavator guidance and monitoring, some research achievements have been yielded based on GNSS positioning in recent years, such as: 1. In Mining Attitude Monitoring System Based on Precise Positioningof Excavator GNSS (Gold Science and Technology, 2016, 24 (4): 101-106), Wang Taihai, Chen Jianhong and Jin Jun preliminarily analyzed the GNSS receiver principle, the three-dimensional coordinate conversion principle, the excavator attitude and the like, indicating that the system has high-precision positioning capability. However, the analysis of the operating state of the excavator was mostly based on the Gauss plane coordinate system or an independent coordinate system (for example, a mine's own coordinate system, a project's own coordinate system, etc.), and a conversion based on the three dimensional coordinate system is difficult. Moreover, big errors are easily generated in the plane coordinate at a specific angle, and the assumption that some angles are 0 cannot meet the high precision requirements. In addition, the report only focused on the effect of the system, but did not involve the detailed implementation process, methods, and the composition and installation of the devices. 2. In Mining Attitude Monitoring System Based on Precise Positioningof Excavator GNSS (Mechanical Management and Development, 2018 (8): 88-90), Zhang Feng combined the mining attitude principle, the GNSS positioning principle, the dual-antenna attitude principle and the visual measurement system, mainly combining the mining attitude, the GNSS positioning and the visual measurement technology to solve the problem with the excavator positioning. And the article related to the video surveillance and intelligent analysis. Visual measurement and analysis itself will generate errors, which will affect the intuition and accuracy of high-precision positioning. In addition, the report did not involve the detailed implementation processes and methods. Therefore, inventing a method for intelligently positioning the walking mechanism and the working devices of an excavator with high precision by adopting the GNSS, high-precision instruments and modem information technological means has great significance in guiding, commanding, monitoring and unmanned operation or less manned operation of an excavator. The existing devices, methods and research results cannot meet the application requirements.

SUMMARY The technical problem to be solved by the invention is how to provide an method for the smart high-precision positioning of excavator based on satellite navigation, so as to overcome the problem that the prior art cannot provide automatic and smart high-precision positioning for excavators. The technical scheme of the invention is as follows:

An method for the smart high-precision positioning of excavator based on satellite navigation, comprising the following steps: step 1, mounting a high-precision GNSS receiver, GNSS receiving antennas, inclination sensors and an on-board computer on an excavator; step 2, calibrating each part of the excavator, wherein a GNSS receiving antenna A is a point A, a GNSS receiving antenna B is a point B, and the orientation of the working devices of the excavator can be determined by the vector relation between the point A and the point B; the connecting point between the big arm and the auxiliary platform is a point R, which is a static point relative to the point A and the point B; the connecting point between the big arm and the small arm is a point C, the connecting point between the small arm and the bucket is a point D, and the head of the bucket is a point E; and the rear contact point of the walking mechanism is a point F, which marks the coordinate position of the chassis; step 3, calibrating the static dimensions of each part of the excavator when the chassis of the excavator is kept horizontal; step 4, reading the real-time dynamic angles of the inclination sensors when the excavator is in the working state; step 5, resolving the real-time differential positioning with the high-precision GNSS receiver to obtain the real-time positioning information of the points A and B in the space rectangular coordinate system and the geodetic coordinate system; step 6, establishing an excavator side view coordinate system Si with the point A as the coordinate origin 0 (0, 0), the vertical direction as an X axis and the advancing direction of the working devices of the excavator as a Y axis, and calculating the coordinates of R, C, D, E and F relative to the point A and the absolute elevation of each point; step 7, establishing an excavator top view coordinate system S2 with the point A as the coordinate origin 0 (0, 0), the advancing direction of the working devices as an X axis and the direction of a connecting line AB as a Y axis, and calculating the coordinates of R, C, D and E relative to the point A; step 8, converting the coordinates of A and B of the space rectangular coordinate system and the geodetic coordinate system into the coordinates of the Gauss plane coordinate system; and marking the converted coordinates as A (aG, aGy, Ha) and B (bGx, bGy, Hb), wherein aGx and bGx are the north coordinates, aGy and bGy are the east coordinates, and Ha and Hb are the absolute elevations; step 9, calculating the conversion parameters from the coordinate system S2 to the Gauss plane coordinate system, converting the coordinates of R, C, D and E of the coordinate system S2 to the coordinates of the Gauss plane coordinate system, and calculating the absolute elevations of R, C, D, E and F by referring to Ha and the coordinate of each point in the reference coordinate system Si relative to A; step 10, converting the Gauss plane coordinate system to other independent coordinate systems; and step 11, completing the smart high-precision positioning of the excavator in the working state. Further, step 1 specifically comprises the following steps: mounting the high-precision GNSS receiver, the GNSS receiving antennas, the inclination sensors and the on-board computer on the excavator; mounting the on-board computer in the cab of the excavator, which is then connected with the inclination sensors and the high-precision GNSS receiver, equipped with a positioning calculation software module, and used for analyzing the working attitudes and converting the coordinates of the excavator; disposing the GNSS receiving antennas at the tail portion of the excavator and connecting the said antennas with the high-precision GNSS receiver, wherein the connecting line between the GNSS receiving antennas is perpendicular to the direction of the excavator cab, and the high-precision GNSS receiver is used for combining the real-time differential signals and the satellite ephemeris data to obtain and analyze the high-precision positioning signal of the GNSS receiving antennas; and mounting the inclination sensors on the working devices of the excavator, that is, on the big arm, the small arm, the bucket and in the cab, which is used to analyze and determine the working attitudes of the excavator.

Further, the inclination sensors are mounted on the working devices of the excavator, that is, on the big arm, the small arm, the bucket and in the cab, which specifically comprises the following steps: mounting the inclination sensor in the pitching and rolling directions of the excavator cab and on the big arm, the small arm and the bucket, which move together with the cab, the big arm, the small arm and the bucket and are used to determine the real-time working attitudes of the cab, the big, the small arm and the bucket, wherein the working attitudes comprise the pitching and rolling conditions of the cab, the vertical height and the horizontal length of the connecting point between the big arm and the excavator platform, the vertical height and the horizontal length of the connecting point between the big arm and the small arm, the vertical length and the horizontal height of the connecting position between the small arm and the bucket, and the vertical length and the level length of the head of the bucket. Further, the static dimensions in step 3 specifically comprise: the distance from the point A to the point R Lf, and the vertical height from the point A to the point F Hy; the length of the big arm, that is, the distance from R to C L, the length of the small arm, that is, the distance from C to D Ld, and the length of the bucket, that is, the distance from D to E Le; the distance between the point A and the intersection point of the perpendicular line connecting the point R to the line AB r sy; the linear distance between the point A and the point B b, and the vertical height difference between the point A and the point R Hr; and A and B having the same height at best, and the connecting line AB being perpendicular to the working devices of the excavator. Further, the real-time dynamic angles comprise the big arm horizontal angle 6, the small arm horizontal angle 6d, the bucket horizontal angle 6e, the cab pitching angle 6 y, and the cab rolling angle 6x. Further, in step 6, the process of calculating the coordinates of R, C, D, E and F in the coordinate system Si relative to the point A and the absolute elevation of each point is as follows: S61, solving the horizontal length and the vertical height of C, D and E relative to the point R: the horizontal length from the point R to the point C l'c: /' = L * cos3

the horizontal length from point R to point D I'd: 1'= 1 + Ld•Cosd

the horizontal length from the point R to the point E l'e: I' e = 7'd + Le 0 cos.o e the vertical height from the point R to the point C h c: h = L • sin3 e cos3

the vertical height from the point R to the point D hd: h= h + Ld* sin d coso

the vertical height from the point R to the point E he: h = h + L e sin 6 e cos 5 e d e e x S62, solving the horizontal lengths of R, C, D and E with the point A as the coordinate origin: horizontal length from the point A to the point R If 1 = Lf cos3 -H *sin 3 f f y r y horizontal length from the point A to the point Cle: c =1 +1' cf c horizontal length from the point A to the point D d: d f

horizontal length from the point A to the point E e: /= +7 ef e S63, solving the absolute elevations of the points C, D, E and F with the point A as the reference point: the absolute elevation of the point R: HwR=Ha+H cosy coso,+Lsin ocoso, the absolute elevation of the point C: Hwc= HWR+h the absolute elevation of the point D: HWD HWR +hd the absolute elevation of the point E: HWE=HWR+h, the absolute elevation of the point F: HWF Ha + Hf cos y 9 cos 6,

Further, in step 7, the process of calculating the coordinates of R, C, D and E in the coordinate system S2 relative to the point A is as follows:

R =f R=Kry cosox

C=r •coso5

D=d D,coso~

F=Klr,•coso6j

Further, in step 9, the conversion parameters from the coordinate system S2 to the Gauss plane coordinate system are calculated, and the process of converting the R, C, D, and E coordinates in the coordinate system S 2 to the Gauss plane coordinate system is as follows: S91, calculating the included angle 0 between the AB vector and the north X axis of the Gauss plane coordinate system:

0= arctan b'y-aGy bGx-aGx

if xGb>XGa andYGb>yGa, 0 > 0 if xGb>XGa andyGb<yGa, 0 < 0 ifxGb<XGa andYGb>yGa, 0 > 0 if xGb<XGa andyGb<yGa, 0 < 0 S92, calculating the conversion angle 8 from the coordinate system S2 to the Gauss plane coordinate system: ifxGb>XGa andYGb>yGa,I3=0-90' ifxGb>XGa andyGb<yGa,I3=0-90 ifxGb<XGa andYGb>yGa,/3=0+90 ifxGb<XGa andyGb<yGa,/3=0±90; S93: calculating the amount of translation of the coordinate system S2 to the Gauss plane coordinate system: Ax | aGx

Ay IaGy.

S94, setting the coordinate of a certain point in the S2 coordinate system as (Xs2, ys2), and converting the coordinate to the Gauss plane as (xG,yG), wherein the relation between them is:

xGj= coS2±coxsi *Y,2±As YG si s*X2 +CS POYs2 +A). S95, converting R, C, D, E and other points from the coordinate system S2 to the Gauss plane coordinate system according to the above method to obtain the coordinates of the Gauss plane coordinate system. Further, in step 10, the process of converting the Gauss plane coordinate system to other independent coordinate systems is as follows: S101, four conversion parameters from the Gauss plane coordinate system to a plane of an independent coordinate system are given: the X-axis translation Axk, the Y-axis translation Ayk, the coordinate conversion angle y, and the conversion parameter K; S102, setting the coordinate of a certain point in the independent coordinate system as (x, yk) and the said coordinate in the Gauss plane as (G, yG):

xY =K cos A -sin A xG k 'in= Ko AxG S YG Xk

Yk j Sin A COSaA yG )+ Ayk Si G + O G k

) S103, given that the conversion parameter from the absolute elevation of the Gauss plane coordinate system to the elevation of an independent coordinate system is Ah, setting the absolute elevation of a certain point as hG and the elevation in the independent coordinate system as hk: hk= hG + Ahk

Further, for the static state, the real-time dynamic angles of the inclination sensors in step 4 are no longer updated in real time, and the other points of the excavator are still calculated according to the method. The invention has the following beneficial effects: The invention provides an method for the smart high-precision positioning of excavator based on satellite navigation, which can facilitate rapid positioning, improve positioning precision, meet the actual working requirements, and provide basic technical support for high-precision guidance, command, monitoring and less manned operation or unmanned operation of excavators. According to the invention, devices such as a receiver, measuring antennas, a single-axle angle sensor, a double-axle angle sensor, and an on-board computer are disposed on the excavator, and the precise positions of the excavator and the main parts thereof can be solved through the Beidou high-precision spatial information technology and analysis algorithm. According to the method, a side-view and a top-view two-dimensional coordinates are constructed, the relative coordinate of each point under the working attitudes of the excavator are reasonably analyzed and solved, and the main components can be precisely positioned through coordinate conversion. Based on accurate positioning, the invention can automatically guide and track the excavator and meet the engineering application requirements of different industries. The invention also has the following advantages: 1. The invention has a clear organization of devices, a clear operating principle, good effects and a stable system structure, which fits in different scenarios and different types of excavators. 2. If the influence of calibration static dimensions, device installation deviation, device errors and the like is excluded, the real-time positioning accuracy of the walking mechanism and working devices of the excavator can reach the centimeter level. 3. The speed of resolving the positioning accuracy can reach the millisecond level, and if the communication network unit is configured, the data can be shared with and utilized by other systems. 4. The intelligent high-precision positioning can simplify the pre-operation preparation, the in- operation guidance and the commanding and monitoring procedure, reduce the workload by not setting out the datum line or driving piles in advance, and improve the working efficiency of the excavator. 5. In different application scenarios, the working efficiency and effect of the excavator can be improved, the excavator can operate precisely and rapidly according to the design requirements, resources and energy can be saved, and damages to the surrounding areas can be reduced. 6. The real-time high-precision positioning of the excavator is improved, the functions of intelligent guidance, operation monitoring and the like of the excavator are enabled, the operation safety is improved, and the unmanned operation or less manned operation of the excavator is facilitated.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of the device connection relation of the present invention; FIG. 2 is a general flowchart of an implementation method of the present invention; FIG. 3 is an explanatory view of the calibration of various parameters of the present invention, wherein (a) is a side view, (b) is a top view, and (c) is a front view; FIG. 4 is a side view of the coordinates of the attitude parameters of the present invention; FIG. 5 is a top view of the coordinates of the attitude parameters of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS In order to make the objectives, contents, and advantages of the present invention clearer, a detailed description of the specific embodiments of the present invention will be given below with reference to the accompanying drawings and examples. The invention provides an smart high-precision positioning system for excavators based on satellite navigation, comprising (FIG. 1): 1-an excavator, 2-a high-precision GNSS receiver, 3-GNSS receiving antennas, 4-inclination sensors, and 5-an on-board computer. The high-precision GNSS receiver, the GNSS receiving antennas, the inclination sensors and the on-board computer are all mounted on the excavator; the on-board computer is mounted in the cab of the excavator, connected with the inclination sensors and the high-precision receiver, and equipped with a special positioning calculation software module; the GNSS receiving antennas are mounted at the tail portion of the excavator and is connected with the high-precision GNSS receiver, and the linear connecting line between the GNSS receiving antennas is basically perpendicular to the direction of the cab of the excavator; and the inclination sensors are mounted on the working devices of the excavator, that is, on the big arm, the small arm, the bucket and in the cab, and are used to analyze and determine the working attitudes of the excavator. The system also comprises a power supply unit for supplying power to the high-precision GNSS receiver, the inclination sensors and the on-board computer. The system further comprises a high-precision GNSS base station for supplying real-time differential data to the high-precision GNSS receiver, wherein the high-precision GNSS base station may be a self-built local base station, or a public base station provided by a non-profit organization such as a government or a telecommunication operator, and the differential signal required by the high-precision GNSS receiver may come from the high-precision GNSS base station or may be obtained by other means. The system further comprises a communication network unit, whereby the information received, processed and stored in the local on-board computer of the excavator is sent to a remote hardware and (or) software system through a wired or wireless network. The excavator is the main carrier of the system, wherein the walking mechanism may be a chassis based on tires, tracks or other forms and the working devices comprise a cab and an auxiliary platform, a big arm, a small arm and a bucket, and the excavator may be a face shovel or a backhoe.

The high-precision GNSS receiver and the receiving antennas are mounted on the excavator and connected to each other. The high-precision GNSS receiver combines the real-time differential signals and the satellite ephemeris data to acquire and analyze the high-precision positioning signals of the GNSS receiving antennas; the excavator is positioned with one of the GNSS receiving antennas as the reference; and the orientation of the excavator is determined by the vector relation between two or more GNSS receiving antennas. The differential signals required by the high-precision GNSS receiver may come from the high-precision GNSS base station or may be obtained by other means, which are aimed at further improving the positioning accuracy of the GNSS receiving antennas. The inclination sensors are mounted in the pitching (front and back) and rolling (left and right) directions of the excavator cab and on the big arm, the small arm and the bucket, move together with the cab, the big arm, the small arm and the bucket, and are used to determine the real-time working attitudes of the cab, the big arm, the small arm and the bucket, wherein the working attitudes specifically comprise the pitching and rolling conditions of the cab, the vertical height and the horizontal length of the connecting point between the big arm and the excavator platform, the vertical height and the horizontal length of the connecting point between the big arm and the small arm, the vertical length and the horizontal height of the connecting position between the small arm and the bucket, and the vertical length and the level length of the head of the bucket (bucket teeth). The horizontal inclination sensors of the big arm, the small arm and the bucket are single-axle inclination sensors, which are used to detect the lifting or lowering angles of the big arm, the small arm and the bucket; and the cab may use two single-axle inclination sensors or one dual-axle inclination sensor, which are(is) used to detect the pitching (front and back) angle and rolling (left and right) angle of the cab. The on-board computer is mounted inside the cab of the excavator and is connected with the inclination sensors and the high-precision GNSS receiver. Besides, the on-board computer has positioning calculation software module, which comprises the high-precision positioning resolving functions of the excavator working attitudes analysis and coordinate conversion.

The invention also provides an method for the smart high-precision positioning of excavator based on satellite navigation, comprising the following steps (FIG. 2): Step 1, mounting the devices according to FIG. 1. The high-precision GNSS receiver, the GNSS receiving antennas, the inclination sensors, the on-board computer and other devices are mounted on the excavator. Step 2, calibrating the calculation parts according to FIG. 3. A GNSS receiving antenna A is a point A, a GNSS receiving antenna B is a point B, and the orientation of the working devices of the excavator can be determined by the vector relation between the point A and the point B; the connecting point between the big arm and the auxiliary platform is a point R, which is a static point relative to the point A and the point B; the connecting point between the big arm and the small arm is a point C, the connecting point between the small arm and the bucket is a point D, and the head of the bucket is a point E; and the rear contact point of the walking mechanism is a point F, which marks the coordinate position of the chassis. Step 3, calibrating the static dimensions according to FIG. 3 when the chassis of the excavator is kept horizontal. The distance from the point A to the point R is Lf, and the vertical height from the point A to the point F is Hy; the length of the big arm (the distance from R to C) is L, the length of the small arm (the distance from C to D) is Ld, and the length of the bucket (the distance from D to E) is Le; the distance between the point A and the intersection point of the perpendicular line connecting the point R to the line AB (the distance between the intersection point of the perpendicular line and AB and the point A after drawing a perpendicular line from the point R to AB) is rsy; the linear distance between the point A and the point B is b, and the vertical height difference between the point A and the point R is Hr; and A and B have the same height at best, and the connecting line AB is perpendicular to the working devices of the excavator at best. Step 4, reading the real-time dynamic angles of the inclination sensors according to FIG. 3 when the excavator is in the working state, wherein the big arm horizontal angle is 6, the small arm horizontal angle is 6d, the bucket horizontal angle is 6e, the cab pitching angle is 6y, and the cab rolling angle is 6x. Step 5, resolving the real-time differential high-precision positioning with the high-precision GNSS receiver to obtain the real-time high-precision positioning information of the points A and B in the space rectangular coordinate system and the geodetic coordinate system. Knowing the precise positions of the antennas A and B is the basis for high-precision positioning of each point of the excavator, and differential positioning is required, that is, with the help of the base station whose precise position is known in advance, the influence of the ephemeris error, satellite clock error, receiver clock error and tropospheric delay error on the user receiver can be weakened or eliminated through the measurement information of the base station. Therefore, in the high-precision positioning of the excavator, a high-precision base station is required to accurately position A and B; and the position of the base station is obtained by calculating after the receiver continuously receives the satellite ephemeris for a long time, and it may be obtained by conventional measurement when the accuracy requirement is not high. Step 6, establishing an excavator side view coordinate system Si according to FIG. 4 with the point A as the coordinate origin 0 (0, 0), the vertical direction as an X axis and the advancing direction of the working devices of the excavator as a Y axis, and calculating the coordinates of R, C, D, E and F relative to the point A and the absolute elevation of each point. The relative position of other parts of the excavator may also be calculated according to FIG. 4. Step 7, establishing an excavator top view coordinate system S2 according to FIG. 5 with the point A as the coordinate origin 0 (0, 0), the advancing direction of the working devices as an X axis and the direction of a connecting line AB as a Y axis, and calculating the coordinates of R, C, D and E relative to the point A. The relative position of other parts of the excavator may also be calculated according to FIG. 5. Step 8, converting the coordinates of A and B of the space rectangular coordinate system and the geodetic coordinate system into the coordinates of the Gauss plane coordinate system. The coordinates of A and B of the space rectangular coordinate system and geodetic coordinate system obtained by the high-precision GNSS receiver are converted into the coordinates of the Gauss plane coordinate system, and the converted coordinates are marked as A (aG,aGy, Ha) and B (bGx, bGy, Hb), wherein aGx and bGx are the north coordinates, aGy and bGy are the east coordinates, and Ha and H are the absolute elevations. Step 9, calculating the conversion parameters from the coordinate system S2 to the Gauss plane coordinate system, converting the coordinates of R, C, D and E of the coordinate system S2 to the coordinates of the Gauss plane coordinate system, and calculating the absolute elevations of R, C, D, E and F by referring to Ha and the coordinate of each point in the coordinate system Si relative to A. Step 10, converting the Gauss plane coordinate system to other independent coordinate systems. According to the conversion parameters from the Gauss plane coordinate system to other independent coordinate systems, the coordinates of R, C, D and E in the Gauss plane coordinate system are converted to other coordinate systems; and the absolute elevations of R, C, D, E and F may also be converted accordingly.

And step 11, completing the smart high-precision positioning of the excavator in the working state. In addition, the static state is a special working state, wherein the only difference is that the parameters in step 4 are no longer updated in real time; and other points of the excavator may be calculated accordingly.

The first key point of the present invention is to calculate the coordinates of R, C, D, E and F in the coordinate system Si relative to the point A and the absolute elevations of R, C, D, E and F in step 6: the first step, as in FIG. 4, solving the horizontal length and the vertical height of C, D and E relative to the point R, wherein when the excavator is basically operating horizontally or the horizontal angle is not large, & and 6y may be approximately 0 with a slight change in the positioning accuracy: the horizontal length from the point R to the point C is 1,:1c = L • cos6

the horizontal length from the point R to point D isI'd: =P +Ld •CoSd

the horizontal length from the point R to the point E is e:/' = /' + L 0 Cos 6 e d e e

the vertical height from the point R to the point C is h:h = L • sin3o cos3

the vertical height from the point R to the point D is h'd: h' = h + Ld sin d coso d c d 'd x

the vertical height from the point R to the point E is he:h = h + L o sin3o coso e d e e x

the second step, solving the horizontal lengths of R, C, D and E with the point A as the coordinate origin: horizontal length from the point A to the point R Ij/ = L .cos 3 -H * sin 5 f f y r y horizontal length from the point A to the point C c:/ c 1+ cf c

horizontal length from the point A to the point D ld: /df

horizontal length from the point A to the point E le: I - I +/ ef e the third step, solving the absolute elevations of the points C, D, E and F with the point A as the reference point:

theabsoluteelevationofthepointR:HwR =H,+H,.cosyocosx+LfosinYocosx

the absolute elevation of the point C: Hwc = HwR+h

the absolute elevation of the point D: HWD = HWR +h

the absolute elevation of the point E: HWE = HWR +h

the absolute elevation of the point F: HF = H, + H • coso coso6

The second key point of the invention is to calculate the coordinates of R, C, D and E in the coordinate system S2 relative to the point A in step 7:

R =f r 0coso6

C= c s

K K D cos

r coso E =e

The third key point of the invention is that in step 8 and step 9 the conversion parameters from the coordinate system S 2 to the Gauss plane coordinate system are calculated, and R, C, D and E in the coordinate system S2 is converted to the Gauss plane coordinate system: the first step, calculating the coordinates of A and B in the Gauss plane coordinate system from the coordinates ofA and B in the space rectangular coordinate system and geodetic coordinate system, and marking the coordinates respectively as A(aG,aGy,Ha) and B(bGx, bGy, Hb), wherein aGx andbG are the eastward coordinates, aGy and bGy are the northward coordinates, and Ha and Hb are the absolute elevations. the second step, calculating the included angle 0 (also called the north angle) between the AB vector and the north X axis of the Gauss plane coordinate system:

0 = arctan bGy~aGy bG-aGx

if XGh>XGa andYGb>YGa,0> 0 if XGh>XGa andYGb<YGa,0< 0 if XGb<XGa andYGb>YGa,0> 0 if XGb<XGa and YGb<YGa,0< 0 the third step, calculating the conversion angle from the coordinate system S2 to the Gauss plane coordinate system: if XGh>XGa andYGb>YGa, P=0-90° if XGh>XGa andYGb<YGa, P=0-90° if XGb<XGa andYGb>YGa,/ =0+90 if XGb<XGa andYGb<YGa, =0+90*; the fourth step, calculating the amount of translation of the coordinate system S2 to the Gauss plane coordinate system:

aGx IAl Jy) 1= aGy. The fifth step, setting the coordinate of a certain point in the S2 coordinate system as (Xs2, ys2), and converting the coordinate to the Gauss plane as (xG,yG), wherein the relation between them is:

XG )s2 s ±s*Y,2 s2A

YG si sX2 +co, 9 s2 + A

the sixth step, converting R, C, D, E and other points from the coordinate system S2 to the Gauss plane coordinate system according to the above method to obtain the coordinates of the Gauss plane coordinate system.

The fourth key point of that invention is to calculate the conversion from the Gauss plane coordinate system of each point to other independent coordinate systems in step 10: the first step, four conversion parameters from the Gauss plane coordinate system to a plane of an independent coordinate system are given: the X-axis translation AXk, the Y-axis translation Ayk, the coordinate conversion angle y, and the conversion parameter K; the second step, setting the coordinate of a certain point in the independent coordinate system as

Kk )= K- [(*A Yk j)sin A EKcos (x, y) and the said coordinate in the Gauss plane as (xG,

-sin A cossA xG

yG yG): =X K cosA•xG - AY)] j= K@KGCsIY Ak G A YSYG ±AXk SAOYG 0 k)

the third step, given that the conversion parameter from the absolute elevation of the Gauss plane coordinate system to the elevation of an independent coordinate system is Ahk, setting the absolute elevation of a certain point as hG and the elevation in the independent coordinate system as hk: hk= hG + Ahk

In an overseas open-pit metal mine, excavators are used for mining operations, with an annual mining output of more than 100 million tons. By positioning the bottom plate height of the excavator (equivalent to the absolute elevation of the point F), the "under-excavation" situation in the excavating process can be determined; by high-precision positioning of the bucket teeth, the consistency between the excavation plan and the actual excavating operation can be guaranteed, and the loss and depletion of the mine can be reduced; and through the high-precision positioning of each point of the excavator, the guiding efficiency can be improved, the operation monitoring can be strengthened, and the ineffective operation can be reduced. The excavators at the mine are Komatsu PC2000 backhoes, which are equipped with the following devices: Name Quantity Mounting Position high-precision GNSS 1set inthecab receiver GNSSreceiving 2 sets excavator tail antenna single-axleinclination 3 sets big arm, small arm and bucket sensor dual-axle inclination 1 set inthe cab sensor on-board computer 1 set in the cab CPE network CPE etwrk1 set in the cab communication unit power supply unit 1 set in the cab

The calibrated static parameters of the excavator are as follows (unit: meter): Parameters Values distance from A to R Lf 5.920785 vertical height from A to F Hf -5.38 length of big arm Le 8.7 length of small arm Ld 3.9 length of bucket Le 3.1 horizontal perpendicular distance between R 1.604383 and AB r'sy. linear distance between point A and point B 3.363938 lb perpendicular height difference between point -2.288 A to point R Hr During the operation of the excavator, the high-precision positioning solution results of the present invention and the positioning results with the conventional measuring instrument have been recorded and compared, as shown below (unit: meter, data rounded to four decimal places), wherein Z represents the absolute elevation. As can be seen from the analysis, in the Gauss plane coordinate system, the average error of the relative static point R in the horizontal X direction is about 0.015m while the average error in the Y direction is about 0.069m, and the average error of the absolute elevation Z is about 0.154m and the average error in horizontal direction is 0.071m; and the average error of the end E of the relative dynamic point in horizontal X direction is about 0.033m while the average error in Y direction is about 0.071m, and the average error of the absolute elevation Z is about 0.189m while the average error in horizontal direction is 0.078. It may be concluded that the horizontal positioning accuracy of the method can be within 0.1m and the accuracy of the elevation positioning can be within 0.2 meters.

Claims

CLAIMS WHAT IS CLAIMED IS: 1. An method for the smart high-precision positioning of excavator based on satellite navigation, comprising the following steps: step 1, mounting a high-precision GNSS receiver, GNSS receiving antennas, inclination sensors and an on-board computer on an excavator; step 2, calibrating each part of the excavator, wherein a GNSS receiving antenna A is a point A, a GNSS receiving antenna B is a point B, and the orientation of working devices of the excavator can be judged by the vector relation between the point A and the point B; the connecting point between the big arm and the auxiliary platform is a point R, which is static relative to the point A and the point B; the connecting point between the big arm and the small arm is a point C, the connecting point between the small arm and the bucket is a point D, and the head of the bucket is a point E; and the rear contact point of the traveling mechanism is a point F, which marks the coordinate position of the chassis; step 3, calibrating the static dimensions of each part of the excavator when the chassis of the excavator is kept horizontal; step 4, reading the real-time dynamic angles of the inclination sensors when the excavator is in the working state; step 5, resolving the real-time differential positioning with the high-precision GNSS receiver to obtain the real-time positioning information of the points A and B in the space rectangular coordinate system and the geodetic coordinate system; step 6, establishing an excavator side view coordinate system Si with the point A as the coordinate origin 0 (0, 0), the vertical direction as an X axis and the advancing direction of the working devices of the excavator as a Y axis, and calculating the coordinates of R, C, D, E and F relative to the point A and the absolute elevation of each point; step 7, establishing an excavator top view coordinate system S2 with the point A as the coordinate origin 0 (0, 0), the advancing direction of the working devices as an X axis and the direction of a connecting line AB as a Y axis, and calculating the coordinates of R, C, D and E relative to the point A; step 8, converting the coordinates ofA and B of the space rectangular coordinate system and the geodetic coordinate system into the coordinates of the Gauss plane coordinate system, and marking the converted coordinates as A (aG,aGy, Ha) and B (bGx, bGy, Hb), wherein aGx and bGx are the north coordinates, aGy and bGy are the east coordinates, and Ha and Hb are the absolute elevations; step 9, calculating the conversion parameters from the coordinate system S2 to the Gauss plane coordinate system, converting the coordinates of R, C, D and E of the coordinate system S2 to the coordinates of the Gauss plane coordinate system, and calculating the absolute elevations of R, C, D, E and F by referring to Ha and the coordinate of each point in the reference coordinate system Si relative to A; step 10, converting the Gauss plane coordinate system to other independent coordinate systems; and step 11, completing the smart high-precision positioning of the excavator in the working state.
2. The smart high-precision positioning method of claim 1, wherein step 1 specifically comprises the following steps: mounting the high-precision GNSS receiver, the GNSS receiving antennas, the inclination sensors and the on-board computer on the excavator; mounting the on-board computer in the cab of the excavator, which is then connected with the inclination sensors and the high-precision GNSS receiver, equipped with a positioning calculation software module, and used for analyzing the working attitude and converting the coordinates of the excavator; disposing the GNSS receiving antennas at the tail portion of the excavator and connecting the said antennas with the high-precision GNSS receiver, wherein the connecting line between the GNSS receiving antennas is perpendicular to the direction of the excavator cab, and the high-precision GNSS receiver is used for combining the real-time differential signals and the satellite ephemeris data to obtain and analyze the high-precision positioning signal of the GNSS receiving antennas; and mounting the inclination sensors on the working devices of the excavator, that is, on the big arm, the small arm, the bucket and in the cab, which is used to analyze and determine the working attitude of the excavator.
3. The smart high-precision positioning method of claim 2, wherein the inclination sensors are mounted on the working devices of the excavator, that is, on the big arm, the small arm, the bucket and in the cab, which specifically comprises the following steps: mounting the inclination sensor in the pitching and rolling directions of the excavator cab and on the big arm, the small arm and the bucket, which move together with the cab, the big arm, the small arm and the bucket and are used to determine the real-time working attitude of the cab, the big, the small arm and the bucket, wherein the working attitude comprises the pitching and rolling conditions of the cab, the vertical height and the horizontal length of the connecting point between the big arm and the excavator platform, the vertical height and the horizontal length of the connecting point between the big arm and the small arm, the vertical length and the horizontal height of the connecting position between the small arm and the bucket, and the vertical length and the level length of the head of the bucket.
4. The smart high-precision positioning method of claim 2 or claim 3, wherein the static dimensions in step 3 specifically comprise: the distance from the point A to the point R Lf, and the vertical height from the point A to the point F H; the length of the big arm, that is, the distance from R to C L, the length of the small arm, that is, the distance from C to D Ld, and the length of the bucket, that is, the distance from D to E Le; the horizontal distance between the point A and the intersection point of the perpendicular line connecting the point R to the line AB r sy; the linear distance between the point A and the point B b, and the vertical height difference between the point A and the point R Hr; and A and B having the same height at best, and the connecting line AB being perpendicular to the working devices of the excavator.
5. The smart high-precision positioning method of claim 4, wherein the real-time dynamic angles comprise the big arm horizontal angle c, the small arm horizontal angle 6d, the bucket horizontal angle 6e, the cab pitching angle 6y, and the cab rolling angle 6x.
6. The smart high-precision positioning method of claim 5, wherein the process of calculating the coordinates of R, C, D, E and F in the coordinate system Si relative to the point A and the absolute elevation of each point in step 6 is as follows: S61, solving the horizontal length and the vertical height of C, D and E relative to the point R: the horizontal length from the point R to the point C is l'1 c = L • cos3 the horizontal length from point R to point D is l'd: ' =1 + Ld Cosd the horizontal length from the point R to the point E is l'e:= 1' +L *cos e d e e the vertical height from the point R to the point C is h c: h =L * sin 63 cos3 the vertical height from the point R to the point D is h'd:h = h +Ld •sin dcos5 d c d d x the vertical height from the point Rto the point E is h'e: h'= h' +L *sin3 *cos.o e d e e x S62, solving the horizontal lengths of R, C, D and E with the point A as the coordinate origin: horizontal length from the point A to the point R 1f. = Lf cos y -Hr sin o f f y r y horizontal length from the point A to the point C le:/ 11 +1 cf c horizontal length from the point A to the point D 1d: d +l horizontal length from the point A to the point E le: 1 +-1 ef e

S63, solving the absolute elevations of the points C, D, E and F with the point A as the reference point:

the absolute elevation of the point R: HwR =H + H, cs cos6,+Lf 9 sin 6, coso,

the absolute elevation of the point C: Hwc= HWR +h

the absolute elevation of the point D: HWD HWR +h

the absolute elevation of the point E: HWE = HWR+h

the absolute elevation of the point F: HWF = Ha + Hf coso,* cos6,
7. The smart high-precision positioning method of claim 6, wherein the process of calculating the coordinates of R, C, D and E in the coordinate system S2 relative to the point A in step 7 is as follows:

R= i r ecoso

D=Kd

E=KcOscx
8. The smart high-precision positioning method of claim 7, wherein in step 9 the conversion parameters from the coordinate system S2 to the Gauss plane coordinate system are calculated, and the process of converting the R, C, D, and E coordinates in the coordinate system S2 to the Gauss plane coordinate system is as follows: S91, calculating the included angle 0 between the AB vector and the north X axis of the Gauss plane coordinate system:

0= arctan b6y-4Gy bGx-aGx

if xGb>XGa andYGb>yGa, 0> 0 if xGb>XGa andyGb<yGa, 0 < 0 ifxGb<XGa and YGb>yGa, 0 > 0 if xGb<XGa andyGb<yGa, 0 < 0 S92, calculating the conversion angle/ $from the coordinate system S2 to the Gauss plane coordinate system: if xGb>XGa andYGb>yGa,I3=0-90' ifxGb>XGa andyGb<yGa,fi=0-90' ifxGb<XGa andYGb>yGa,/3=0+90 ifxGb<XGa andyGb<yGa,/3=0±90; S93: calculating the amount of translation of the coordinate system S2 to the Gauss plane coordinate system: A aGx

Ay IaGy_.

ys2), and S94, setting the coordinate of a certain point in theS2coordinate system as (xs2, converting the coordinate to the Gauss plane as (xG,yG),wherein the relation between them is:

XG )=cosi xs2 - sn 8* Ys2A

YG ) sX,2 +* C S2* Ay S95, converting R, C, D, E and other points from the coordinate systemS2 to the Gauss plane coordinate system according to the above method to obtain the coordinates of the Gauss plane coordinate system.
9. The smart high-precision positioning method of claim 8, wherein the process of converting the Gauss plane coordinate system to other independent coordinate systems in step 10 is as follows: S101, four conversion parameters from the Gauss plane coordinate system to a plane of an independent coordinate system are given: the X-axis translation Axk, the Y-axis translation Ay, the coordinate conversion angle y, and the conversion parameter K; S102, setting the coordinate of a certain point in the independent coordinate system as (xk, yk) and the said coordinate in the Gauss plane as (G, yG): Xk = K• cosA -sin A xG k)± =K•os A• xG AG k

Yk Sin A COs A yG ) k Sin XG COSAYG +Xk S103, given that the conversion parameter from the absolute elevation of the Gauss plane coordinate system to the elevation of an independent coordinate system is Ahk, setting the absolute elevation of a certain point as hGand the elevation in the independent coordinate system as hk: hk= hG+Ahk
10. The smart high-precision positioning method of claims 5-9, wherein, for the static state, the real-time dynamic angles of the inclination sensors in step 4 are no longer updated in real time, and the other points of the excavator are still calculated according to the method.