阅读说明：本技术 一种基于agv与激光跟踪仪的组合定位装置及方法 (Combined positioning device and method based on AGV and laser tracker ) 是由 汪俊 杨建平 曾坤 刘炼 张伟 于 2020-06-28 设计创作，主要内容包括：本发明涉及一种基于AGV和激光跟踪仪组合定位装置及方法,其采用搭建可自主导航与定位的AGV平台作为移动平台,可搭载多种三维测量设备,实现大规模测量过程中测量位置的全自动转移,提高整体测量效率。将激光跟踪仪的测量数据与AGV的定位数据进行融合处理,通过基准点匹配算法实现辅助基准点的识别与编号,采用平差法优化辅助基准点测量误差,自动构建高精度测量场,具有保证测量场整体精度,避免频繁的数据导出、数据整理等优势。通过AGV与双目摄影测量装置结合,自动对基准点进行测量,借助辅助基准点匹配方法,将测量基准点测量坐标投影至测量场全局坐标系中,避免因测量位置转移带来的测量误差积累问题,可实现部件的高精度定位。(The invention relates to a positioning device and a positioning method based on AGV and laser tracker combination, which adopt an AGV platform which is built and can be automatically navigated and positioned as a mobile platform, can carry various three-dimensional measuring devices, realizes full-automatic transfer of measuring positions in a large-scale measuring process, and improves the overall measuring efficiency. The method has the advantages that the measurement data of the laser tracker and the positioning data of the AGV are fused, the identification and the numbering of the auxiliary reference points are realized through a reference point matching algorithm, the measurement error of the auxiliary reference points is optimized by adopting a balance method, a high-precision measurement field is automatically constructed, the overall precision of the measurement field is ensured, and frequent data derivation, data arrangement and the like are avoided. The AGV is combined with a binocular photogrammetric device to automatically measure the reference point, and the measurement coordinate of the measurement reference point is projected into a global coordinate system of a measurement field by means of an auxiliary reference point matching method, so that the problem of measurement error accumulation caused by measurement position transfer is avoided, and high-precision positioning of components can be realized.)

1. A combined positioning device based on an AGV and a laser tracker is characterized by comprising a moving platform (1) and the laser tracker (4), wherein the upper end face of the moving platform (1) is fixedly provided with a lifting platform (2), a system control module (5) and a system power supply module (6), and the laser tracker (4) is fixedly arranged on the lifting platform (2); moving platform (1) is the AGV platform that has laser radar positioning system, and system power module (6) do the power supply of combination positioner, moving platform (1), lift platform (2) and laser tracker (4) respectively with system control module (5) signal connection.

2. The combined positioning device based on the AGV and the laser tracker of claim 1, further comprising a tripod (3), wherein the tripod (3) is fixed on the upper end surface of the lifting platform (2), and the laser tracker (4) is fixedly arranged on the top of the tripod (3).

3. The combined positioning device based on the AGV and the laser tracker according to claim 2, wherein the lifting platform (2) comprises a middle connecting plate (23), three vertically arranged electric push rods (21) and a single chip microcomputer (22) for controlling the three electric push rods (21) to stretch, the bottoms of the electric push rods (21) are fixed on the moving platform (1) through screws, and the middle connecting plate (23) is horizontally arranged and is respectively fixedly connected with the tops of the three electric push rods (21) through screws; the bottom of the tripod (3) is fixed on the middle connecting plate (23) through a bolt, and the singlechip (22) is fixed on the outer side surface of any electric push rod (21); the system control module (5) is an industrial personal computer carrying a wireless network card, and the system control module (5) is in wireless communication connection with the single chip microcomputer (22), the laser tracker (4) and the mobile platform (1) respectively.

4. A combined positioning device based on AGV and laser tracker according to claim 3, characterized in that the initial height of any electric push rod (21) is 600mm and the maximum height of the lift is 1100 mm; the height of the tripod (3) is 500 mm.

5. Combined positioning device based on AGV and laser tracker according to any of the claims 1 to 4 characterized in that the system power supply module (6) uses industrial mobile power supply.

6. A combined positioning method based on an AGV and a laser tracker is characterized by comprising the following steps:

step S1, arranging a plurality of multi-purpose targets in the measuring field as auxiliary reference points, wherein the arrangement number of the multi-purpose targets is ensured to cover the whole measuring field space;

step S2, driving the mobile platform (1), and starting laser radar scanning to construct a navigation map;

step S3, adjusting the lifting platform (2) according to the height of the measuring field to enable the laser tracker (4) to reach the height of half of the measuring field;

step S4, driving the mobile platform (1) to any measuring station position, recording the current space position of the laser tracker (4) as a measuring origin, measuring all auxiliary reference points within a set distance range from the measuring origin through the laser tracker (4), and driving the mobile platform (1) to the next measuring station position after the measuring of the measuring station position is finished until all auxiliary reference points are measured; when a single auxiliary datum point is measured, a tracking target ball is held by hand to activate the laser tracker (4), the tracking target ball is placed on the multipurpose target, and the measurement value of the laser tracker (4) is read; in the navigation map, the identification and numbering of each auxiliary reference point are realized by adopting the existing auxiliary reference point matching algorithm;

step S5, calculating coordinates of the auxiliary reference points and constructing a high-precision measuring field by using a balancing method;

step S6, arranging a photogrammetric target on the component to be positioned as a measurement reference point;

s7, detaching the laser tracker (4) and the tripod (3), installing and arranging the binocular photogrammetry device on the lifting platform (2), driving the moving platform (1) to move along an artificially set path, measuring a measurement reference point, and simultaneously measuring an auxiliary reference point again through the binocular photogrammetry device; and aligning each measuring reference point to a high-precision measuring field by matching the auxiliary reference points, and calculating the global coordinate of each measuring reference point to realize the positioning of the measuring reference points.

7. The AGV and laser tracker based combined positioning method of claim 6, wherein the step S4 specifically comprises:

step S401, reading all auxiliary reference point space coordinate sets of the first measuring station position

step S402, reading all auxiliary reference point space coordinate sets of the next measuring station positionAnd the laser tracker (4) currently corresponds to a space positioning coordinate O_jJ is the number of the measuring station, and t is the number of the auxiliary reference points under the position of the corresponding measuring station; set P_jAuxiliary reference point space coordinate and space positioning coordinate O in_jAdding to obtain a set T_j；

Step S403, finding out a total set M and a set T of auxiliary reference points through an ICP (inductively coupled plasma) matching algorithm_jA common auxiliary reference point G;

step S404, calculating an auxiliary reference point difference set N_j＝T_jG, set N_jThe auxiliary reference points in the auxiliary reference point total set M are added into the auxiliary reference point total set M, and numbers are added;

step S405, if the station position is measured at the last station, ending the measurement, and obtaining a final auxiliary reference point total set M; otherwise, step S402 to step S404 are executed.

8. The AGV and laser tracker based combined positioning method of claim 7, wherein the step S7 specifically comprises:

s701, detaching the laser tracker (4) and the tripod (3), and installing the binocular photogrammetric device on the middle connecting plate (23) through bolts; drawing a motion path of the mobile platform (1) on a navigation map, and setting a positioning acquisition interval to be L;

step S702, starting an autonomous navigation mode of the mobile platform (1), and pausing the movement of the mobile platform (1) along a movement path for every L distance;

step S703, starting the binocular photogrammetry device, and measuring all auxiliary reference points and measurement reference points in the visual angle to obtain a reference point measurement setWherein k is the number of the binocular photogrammetry position, and s is the number of the reference point;

step S704, finding out a set W by using RANSAC matching algorithm_kAnd a common auxiliary reference point set B in the auxiliary reference point total set M, and calculating a set difference set C_k＝W_kB, obtaining a set of measurement reference points C_k；

Step S705, if the number of the common auxiliary reference points in the auxiliary reference point set B is 4 or more, the measurement reference point set C is converted according to the common point_kMapping the measurement reference point to a high-precision measurement field to realize global positioning of the measurement reference point;

step S706, repeating the step S703 to the step S705 until the moving platform (1) finishes the whole motion path.

Technical Field

The invention belongs to the field of high-precision positioning, and particularly relates to a combined positioning device and method based on an AGV and a laser tracker.

Background

In recent years, the aviation manufacturing industry in China is rapidly developed, and various novel airplanes such as supersonic speed, super stealth, super large-scale airplanes are successfully researched and developed and put into batch production. However, many problems to be solved, such as high-precision measurement of large aircraft parts and overall appearance, are exposed in the production process.

At present, in the measurement of the appearance of large-scale aircraft parts and complete machines, dense targets or target balls are usually placed on an object to be measured as a common reference point, then, a handheld laser scanner is adopted to scan in a substation mode to obtain local measurement point clouds, and a local point cloud data splicing method is adopted to generate the overall measurement point clouds. The method solves the conversion relation of the point cloud data coordinate system between the adjacent stations by matching the common reference points between the adjacent stations, thereby realizing the positioning of the measuring target ball. In the measuring process of large-scale aircraft parts and complete machine appearance, manual station transfer is frequently required, error accumulation can occur in the point cloud data splicing process, and the problems of low automation degree, high labor intensity, low measuring efficiency and the like exist.

Disclosure of Invention

The invention provides a combined positioning device and method based on an AGV and a laser tracker, which have the advantages of high automation degree, low cost, easiness in control and high positioning efficiency and precision.

The technical scheme adopted by the invention is as follows:

a combined positioning device based on an AGV and a laser tracker comprises a mobile platform and the laser tracker, wherein the upper end face of the mobile platform is fixedly provided with a lifting platform, a system control module and a system power supply module, and the laser tracker is fixedly arranged on the lifting platform; the moving platform is an AGV platform with a laser radar positioning system, a system power supply module is used for supplying power to the combined positioning device, and the moving platform, the lifting platform and the laser tracker are respectively connected with a system control module through signals.

Further, the combined positioning device based on the AGV and the laser tracker further comprises a tripod, the tripod is fixed on the upper end face of the lifting platform, and the laser tracker is fixedly arranged at the top of the tripod.

Furthermore, the lifting platform comprises a middle connecting plate, three vertically arranged electric push rods and a single chip microcomputer for controlling the three electric push rods to stretch, the bottoms of the electric push rods are fixed on the moving platform through screws, and the middle connecting plate is horizontally arranged and is respectively fixedly connected with the tops of the three electric push rods through screws; the bottom of the tripod is fixed on the middle connecting plate through a bolt, and the single chip microcomputer is fixed on the outer side surface of any electric push rod; the system control module is an industrial personal computer carrying a wireless network card, and the system control module is in wireless communication connection with the single chip microcomputer, the laser tracker and the mobile platform respectively.

Further, the initial height of any electric push rod is 600mm, and the maximum rising height is 1100 mm; the height of the tripod is 500 mm.

Further, the system power supply module adopts an industrial mobile power supply.

A combined positioning method based on an AGV and a laser tracker comprises the following steps:

step S1, arranging a plurality of multi-purpose targets in the measuring field as auxiliary reference points, wherein the arrangement number of the multi-purpose targets is ensured to cover the whole measuring field space;

step S2, driving the mobile platform, and starting laser radar scanning to construct a navigation map;

step S3, adjusting the lifting platform according to the height of the measuring field to make the laser tracker reach half of the height of the measuring field;

step S4, driving the mobile platform to any measuring station position, recording the current space position of the laser tracker as a measuring origin, measuring all auxiliary reference points within a set distance range from the measuring origin through the laser tracker, and driving the mobile platform to the next measuring station position after the measuring of the measuring station position is finished until all auxiliary reference points are measured; when a single auxiliary datum point is measured, a tracking target ball is held by hand to activate the laser tracker, the tracking target ball is placed on the multi-purpose target, and the measurement value of the laser tracker is read; in the navigation map, the identification and numbering of each auxiliary reference point are realized by adopting the existing auxiliary reference point matching algorithm;

step S5, calculating coordinates of the auxiliary reference points and constructing a high-precision measuring field by using a balancing method;

step S6, arranging a photogrammetric target on the component to be positioned as a measurement reference point;

step S7, detaching the laser tracker and the tripod, arranging the binocular photogrammetry device on the lifting platform, driving the moving platform to move along the artificially set path, measuring the measurement reference point, and simultaneously measuring the auxiliary reference point again through the binocular photogrammetry device; and aligning each measuring reference point to a high-precision measuring field by matching the auxiliary reference points, and calculating the global coordinate of each measuring reference point to realize the positioning of the measuring reference points.

Further, step S4 specifically includes:

step S401, reading all auxiliary reference point space coordinate sets of the first measuring station positionWherein i is the number of auxiliary reference points under the station; reading current space positioning coordinate O of laser tracker₁Set P with (x, y, z) as the origin₁Auxiliary reference point space coordinates and origin O₁Adding the data to an auxiliary reference point total set M, numbering the data in sequence, and initially setting the auxiliary reference point total set M as an empty set;

step S402, reading all auxiliary reference point space coordinate sets of the next measuring station positionAnd the current corresponding space positioning coordinate O of the laser tracker_jJ is the number of the measuring station, and t is the number of the auxiliary reference points under the position of the corresponding measuring station; set P_jAuxiliary reference point space coordinate and space positioning coordinate O in_jAdding to obtain a set T_j；

Step S403, finding out a total set M and a set T of auxiliary reference points through an ICP (inductively coupled plasma) matching algorithm_jA common auxiliary reference point G;

step S404, calculating an auxiliary reference point difference set N_j＝T_jG, set N_jThe auxiliary reference points in the auxiliary reference point total set M are added into the auxiliary reference point total set M, and numbers are added;

step S405, if the station position is measured at the last station, ending the measurement, and obtaining a final auxiliary reference point total set M; otherwise, step S402 to step S404 are executed.

Further, step S7 specifically includes:

s701, detaching the laser tracker and the tripod, and installing the binocular photogrammetric device on a middle connecting plate through bolts; drawing a moving path of the mobile platform on a navigation map, and setting a positioning acquisition interval to be L;

step S702, starting an autonomous navigation mode of the mobile platform, and pausing the movement of the mobile platform every L distance of movement along a movement path;

step S703, starting the binocular photogrammetry device, and measuring all auxiliary reference points and measurement reference points in the visual angle to obtain a reference point measurement set

Wherein k isThe binocular photogrammetry position is numbered, and s is the number of the reference point;

step S704, finding out a set W by using RANSAC matching algorithm_kAnd a common auxiliary reference point set B in the auxiliary reference point total set M, and calculating a set difference set C_k＝W_kB, obtaining a set of measurement reference points C_k；

Step S705, if the number of the common auxiliary reference points in the auxiliary reference point set B is 4 or more, the measurement reference point set C is converted according to the common point_kMapping the measurement reference point to a high-precision measurement field to realize global positioning of the measurement reference point;

step 706, repeating step 703 to step 705 until the mobile platform finishes the whole motion path.

The invention has the beneficial effects that:

according to the combined positioning device and method based on the AGV and the laser tracker, a drive is constructed based on a measuring field, the AGV platform which can be automatically navigated and positioned is constructed to serve as a measuring moving platform, various three-dimensional measuring equipment can be carried, full-automatic transfer of measuring positions in a large-scale measuring process is achieved, and the overall measuring efficiency is improved. According to the method, the measurement data of the laser tracker and the positioning information of the AGV are subjected to fusion processing, the identification and numbering of the auxiliary reference points are realized through a reference point matching algorithm, then the adjustment method is adopted, the measurement error of the auxiliary reference points is optimized, the high-precision measurement field is automatically constructed, and the method has the advantages of ensuring the overall precision of the measurement field, avoiding frequent data export, data arrangement and the like. The AGV is combined with a binocular photogrammetric device, the reference point is automatically measured, and then the measurement coordinate of the measurement reference point is projected into the global coordinate of a measurement field by means of an auxiliary reference point matching method, so that the problem of measurement error accumulation caused by measurement position transfer is avoided, and high-precision positioning of the component is realized.

Drawings

FIG. 1 is a schematic diagram of a combined AGV and laser tracker based positioning apparatus of the present invention;

FIG. 2 is a block diagram of a flow chart of a combined positioning method based on an AGV and a laser tracker.

Reference numerals: the system comprises a mobile platform 1, a lifting platform 2, an electric push rod 21, a single chip microcomputer 22, an intermediate connecting plate 23, a tripod 3, a laser tracker 4, a system control module 5 and a system power supply module 6.

Detailed Description

The positioning device and method based on AGV and laser tracker according to the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.

As shown in FIG. 1, the combined positioning device based on the AGV and the laser tracker comprises a moving platform 1 and the laser tracker 4, wherein a lifting platform 2, a system control module 5 and a system power supply module 6 are fixedly carried on the upper end face of the moving platform 1, and the laser tracker 4 is fixedly arranged on the lifting platform 2. The moving platform 1 is an AGV platform with a laser radar positioning system (the indoor positioning accuracy is 100mm), the system power supply module 6 supplies power for the combined positioning device, and the moving platform 1, the lifting platform 2 and the laser tracker 4 are respectively in signal connection with the system control module 5. The system control module 5 is used for controlling the moving platform 1 to move, the lifting platform 2 to lift and the processing of the positioning data.

As a further scheme, the combined positioning device based on the AGV and the laser tracker further comprises a tripod 3, the tripod 3 is fixed on the upper end face of the lifting platform 2, and the laser tracker 4 is fixedly arranged at the top of the tripod 3.

Specifically, lift platform 2 includes intermediate junction board 23, the flexible singlechip 22 of three electric putter 21 of three vertical setting and being used for controlling (by system control module 5 with signal transmission for singlechip 22, carry out flexible control by singlechip 22 again), and fix with screw is passed through on moving platform 1 in electric putter 21 bottom, and intermediate junction board 23 level sets up and passes through screw fixed connection with three electric putter 21 tops respectively. The bottom of the tripod 3 is fixed on the middle connecting plate 23 through a bolt, and the singlechip 22 is fixed on the outer side surface of any electric push rod 21. The system control module 5 is an industrial personal computer carrying a wireless network card, and the system control module 5 is in wireless communication connection with the single chip microcomputer 22, the laser tracker 4 and the mobile platform 1 respectively.

In this embodiment, the initial height of any one of the electric push rods 21 is 600mm, and the maximum height of the electric push rod is 1100 mm. The height of the tripod 3 is 500 mm. The system power supply module 6 adopts an industrial mobile power supply.

As shown in fig. 2, a combined positioning method based on AGV and laser tracker includes the following steps:

step S1, arranging a plurality of multi-purpose targets as auxiliary reference points in the measuring field (including the ground and the columns), wherein the number of the multi-purpose targets is ensured to cover the whole measuring field space, and in this embodiment, the distance between adjacent multi-purpose targets is controlled to be about 2 meters.

And step S2, driving the mobile platform 1, and starting laser radar scanning to construct a navigation map.

And step S3, adjusting the lifting platform 2 according to the height of the measuring field, so that the laser tracker 4 reaches half of the height of the measuring field.

Step S4, driving the mobile platform 1 to any measurement station position, recording the current spatial position of the laser tracker 4 as a measurement origin, measuring all auxiliary reference points within a set distance (in this embodiment, the set distance is 5 meters) from the measurement origin by the laser tracker 4, and after the measurement of the measurement station position is completed, driving the mobile platform 1 to the next measurement station position until all auxiliary reference points are completely measured. When a single auxiliary datum point is used for measurement, the laser tracker 4 is activated by holding one tracking target ball by hand, the tracking target ball is placed on the multipurpose target, and the measurement value of the laser tracker 4 is read. In the navigation map, the identification and numbering of each auxiliary reference point are realized by adopting the existing auxiliary reference point matching algorithm.

And step S5, resolving the coordinates of the auxiliary reference points and constructing a high-precision measuring field by using a balancing method.

And step S6, arranging the photogrammetric target on the component to be positioned as a measurement reference point.

And step S7, detaching the laser tracker 4 and the tripod 3, installing and arranging the binocular photogrammetry device on the lifting platform 2, driving the moving platform 1 to move along an artificially set path, measuring the measurement reference point, and simultaneously measuring the auxiliary reference point again through the binocular photogrammetry device. And aligning each measuring reference point to a high-precision measuring field by matching the auxiliary reference points, and calculating the global coordinate of each measuring reference point to realize the positioning of the measuring reference points.

Step S4 specifically includes:

step S401, reading all auxiliary reference point space coordinate sets of the first measuring station positionWherein i is the number of the auxiliary reference points under the station position. Reading the current space positioning coordinate O of the laser tracker 4₁Set P with (x, y, z) as the origin₁Auxiliary reference point space coordinates and origin O₁And adding the data to the total auxiliary reference point set M, and numbering the data in sequence, wherein the total auxiliary reference point set M is initially an empty set.

Step S402, reading all auxiliary reference point space coordinate sets of the next measuring station positionAnd the laser tracker 4 currently corresponds to a space positioning coordinate O_jWherein j is the number of the measuring station, and t is the number of the auxiliary reference points under the position of the corresponding measuring station. Set P_jAuxiliary reference point space coordinate and space positioning coordinate O in_jAdding to obtain a set T_j。

Step S403, finding out a total set M and a set T of auxiliary reference points through an ICP (inductively coupled plasma) matching algorithm_jOf the reference point G.

Step S404, calculating an auxiliary reference point difference set N_j＝T_jG, set N_jThe auxiliary reference points in (b) are added to the total set of auxiliary reference points M and the numbers are added.

And S405, if the station position is measured at the last station, ending the step, and obtaining a final auxiliary reference point total set M. Otherwise, step S402 to step S404 are executed.

Step S7 specifically includes:

and S701, detaching the laser tracker 4 and the tripod 3, and installing the binocular photogrammetric device on the middle connecting plate 23 through bolts. And drawing a motion path of the mobile platform 1 on the navigation map, and setting a positioning acquisition interval to be L.

Step S702, starting the autonomous navigation mode of the mobile platform 1, and pausing the movement of the mobile platform 1 along the movement path by every distance L.

Step S703, starting the binocular photogrammetry device, and measuring all auxiliary reference points and measurement reference points in the visual angle to obtain a reference point measurement set

Wherein k is the binocular photogrammetry position number, and s is the number of the reference point.

Step S704, finding out a set W by using RANSAC matching algorithm_kAnd a common auxiliary reference point set B in the auxiliary reference point total set M, and calculating a set difference set C_k＝W_kB, obtaining a set of measurement reference points C_k。

Step S705, if the number of the common auxiliary reference points in the auxiliary reference point set B is 4 or more, the measurement reference point set C is converted according to the common point_kThe measuring reference points in the measuring device are mapped to a high-precision measuring field, and the global positioning of the measuring reference points is realized.

Step S706, repeating step S703 to step S705 until the mobile platform 1 finishes the entire movement path.

The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the invention may be made by those skilled in the art without departing from the principle of the invention.