CN110045387B - Intelligent support shield type hydraulic support posture monitoring system and measurement method thereof - Google Patents
Intelligent support shield type hydraulic support posture monitoring system and measurement method thereof Download PDFInfo
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- CN110045387B CN110045387B CN201910327447.2A CN201910327447A CN110045387B CN 110045387 B CN110045387 B CN 110045387B CN 201910327447 A CN201910327447 A CN 201910327447A CN 110045387 B CN110045387 B CN 110045387B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
- G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
- G01S17/06—Systems determining position data of a target
- G01S17/42—Simultaneous measurement of distance and other co-ordinates
Abstract
The invention discloses an intelligent monitoring system for the posture of a support shield type hydraulic support and a measuring method thereof, and aims to solve the defects of more types and quantity of sensors, poor reliability and low precision required by the existing monitoring method. The intelligent monitoring system for the posture of the supporting shield type hydraulic support comprises an intelligent monitoring device and an upper computer; the intelligent monitoring device comprises a 3-axis inclination sensor, a measurement and control host and a laser radar. During measurement, the intelligent monitoring device is fixedly arranged on the base supporting the middle position of the two front upright posts of the shield hydraulic support. The 3-axis inclination angle sensor monitors the inclination angle of the base of the hydraulic support in real time; the laser radar scans and measures the distance in the vertical direction inside the hydraulic support, and the measured and output point cloud data are converted to calculate the linear characteristic equation of the end faces of each supporting member and the front and rear hydraulic upright posts of the supporting shield type hydraulic support, so that the posture of the supporting shield type hydraulic support is monitored. The invention has the advantages of few application sensors, high measurement precision, quick installation and convenient overhaul and maintenance.
Description
Technical Field
The invention relates to a system and a method for detecting the posture of a hydraulic support of a fully-mechanized coal mining face in a coal mine, in particular to a system and a method for detecting the posture of a supporting shield type hydraulic support.
Technical Field
The supporting shield type hydraulic support is one of the main flow forms of the hydraulic support, and plays an important role in not only supporting a coal face under a mine but also pushing a scraper conveyor and a coal cutter. Along with the increasing demand of unattended operation under mines, intelligent mining of fully mechanized mining face becomes the main development direction of coal production, and the demand of real-time monitoring of the posture of a supporting shield hydraulic support is also increasing, but the research of real-time monitoring of the posture of the supporting shield hydraulic support at the present stage is imperfect. The existing sensors required for monitoring the posture of the support shield type hydraulic support are large in variety, large in number and complex in structure, so that the measurement accuracy is low, the system reliability is poor, and the later maintenance workload is large. The intelligent monitoring system for the posture of the support shield type hydraulic support and the measuring method thereof provided by the invention have the advantages of fewer sensors, high reliability and great improvement on the accuracy of monitoring data.
Disclosure of Invention
The invention provides an intelligent monitoring system for the posture of a support shield type hydraulic support and a measuring method thereof, and aims to solve the defects of more types and quantity of sensors, poor reliability and low precision required by the existing monitoring method. The intelligent monitoring system for the posture of the supporting shield type hydraulic support comprises an intelligent monitoring device and an upper computer; the intelligent monitoring device comprises a 3-axis inclination sensor, a measurement and control host and a laser radar. During measurement, the intelligent monitoring device is fixedly arranged on the base supporting the middle position of the two front upright posts of the shield hydraulic support. The 3-axis inclination angle sensor monitors the inclination angle of the base of the hydraulic support in real time; the laser radar scans and measures the distance in the vertical direction inside the hydraulic support, the point cloud data which are measured and output are processed through Hough transformation and Kalman filtering, and the linear characteristic equation of the end faces of each support member and the front and rear hydraulic upright posts of the support shield type hydraulic support is solved, so that the posture monitoring of the support shield type hydraulic support is realized. The invention has the advantages of few application sensors, high measurement precision, quick installation and convenient overhaul and maintenance.
Technical proposal
In order to achieve the above object, the intelligent monitoring system for the posture of the support shield type hydraulic support comprises an intelligent monitoring device and an upper computer; the intelligent monitoring device is mining explosion-proof electrical equipment and comprises a two-dimensional laser radar, a 3-axis inclination sensor and a measurement and control host, wherein the measurement and control host and the 3-axis inclination sensor are fixed in a shell of the intelligent monitoring device, and the two-dimensional laser radar is fixed outside the shell; the intelligent monitoring device is fixedly arranged on the steel plate of the base of the supporting shield type hydraulic support and is positioned between the two front upright posts; the measurement and control host computer supplies power, controls, receives data and processes the data to the laser radar and the inclination angle sensor through the cable, and transmits the resolving result to the upper computer.
The intelligent monitoring device is fixedly arranged on the plane of the base steel plate of the hydraulic support and is positioned between the two front upright posts, and the installation position is such that the axle center of the two-dimensional laser radar of the intelligent monitoring device and the axle centers of the two front upright posts are positioned on the same plane. During measurement, the measurement and control host controls the laser radar to rotate 180 degrees in the vertical direction in the space above the device in the support shield type hydraulic support to perform ranging scanning, so as to obtain a group of point cloud data, wherein the distance and the rotation included angle between discrete points on each mechanical surface of the support shield type hydraulic support and the monitoring device can be expressed as (r) i ，α i ) (i=1, 2,3,) n. The linear equation of each component end face of the supporting shield type hydraulic support is obtained through Hough transformation and Kalman filtering processing on the point cloud data output by laser scanning, the linear equation of the front and rear upright posts is calculated through the equation of each end face and the known parameters of the hydraulic support, and finally the attitude parameters of the supporting shield type hydraulic support can be known.
Compared with the existing technology and research results, the invention has the advantages that the variety and the number of the sensor devices used are obviously reduced, the measurement accuracy is higher, the reliability of the system is improved, and the intelligent monitoring device is easy to install and maintain. The intelligent monitoring system for the posture of the support shield type hydraulic support and the measuring method thereof make up for the defect of the existing posture monitoring of the hydraulic support, and provide good technical support for realizing unmanned and unattended operation in the pit.
Drawings
Fig. 1 is a front view of an installation diagram of a smart device according to the present invention.
Fig. 2 is a top view of the smart device installation of the present invention.
Fig. 3 is a block diagram of the intelligent device of the present invention.
Fig. 4 is an overall construction diagram of the present invention.
Fig. 5 is a view of the measured start angle and column state of the present invention.
1-intelligent monitoring device, 2-base, 3-front pillar, 4-side protection board, 5-back timber, 6-host computer, 101-laser radar, 102-measurement and control host computer, 103-3 axis inclination sensor.
Detailed description of the preferred embodiments
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
As shown in fig. 1 and 2, the intelligent monitoring device 1 for supporting the attitude of the shield type hydraulic support is fixed on the base 2 supporting the shield type hydraulic support, and the axle center of the laser radar 101 of the intelligent monitoring device and the axle centers of the first two upright posts 3 of the hydraulic support are on the same plane during installation.
As shown in fig. 3, the intelligent monitoring device 1 includes a laser scanning radar 101 fixedly installed outside the casing, a measurement and control host 102 and a 3-axis tilt sensor 103 fixedly installed inside the casing, and the measurement and control host 102 supplies power to and controls the laser radar 101 through a cable.
The intelligent monitoring system for the posture of the support shield type hydraulic support is divided into two working modes of timing and manual operation. When in the timing mode, the mine remote control center starts the monitoring mode for the intelligent monitoring device at fixed time, and sets the monitoring stop time. In the manual mode, the staff starts or stops the intelligent monitoring device to work according to the requirements on the operation interface of the upper computer 6. Under two working modes, the 3-axis inclination angle sensor is always in a working state, and when the inclination angle change output by the 3-axis inclination angle sensor is larger than a set threshold value, the intelligent monitoring device automatically starts a monitoring mode and uploads a measurement result to the upper computer 6.
When the intelligent monitoring device 1 is in a working state, as shown in fig. 4, with the axis of the intelligent monitoring device 101 as the origin, a rectangular coordinate system is established, and the inclination angle transmitted by the 3-axis inclination sensor and the distance between the laser radar axis and the base can obtain a linear equation of the base, which can be expressed as:
l e ：y＝k e x+m e
the laser radar performs 180-degree rapid ranging scanning in the vertical direction inside the hydraulic support, and after one scanning is completed, the laser radar outputs a group of point cloud data which represents the distance from the discrete point of laser irradiation to each surface in the hydraulic support to the measurement starting point and the rotation included angle during scanning, and can be expressed as (r i ，α i )(i＝1,2,3，...，n)。
Further, as shown in FIG. 4, the horizontal tilt angle of the hydraulic bracket measured and output by the 3-axis tilt angle sensor is alpha 0 The point cloud data output by the radar is corrected to (r) i ，α i -α 0 ) (i=1, 2,3,) n. Extracting 4 optimal straight lines through Hough transformation and Kalman filtering, and correspondingly supporting straight line equations of a side protection plate, a top beam, a shield beam and a front connecting rod component of the shield hydraulic support in a laser scanning space plane, wherein the straight line equations are respectively expressed as follows:
l a :y＝k a x+m a
l b :y＝k b x+m b
l c :y＝k c x+m c
l d :y＝k d x+m d
further, the coordinates of the intersection A, C, D, E of the straight lines a and b, b and c, c and d, d and e in space are respectively:
further, according to the length of the top beam and the A, C, the telescopic length of the front beam can be obtained:
L AB ＝L AC -L BC
wherein:
further, as shown in FIG. 5, the distance from the point A to the hinge point of the front upright and the top beam is L 1 The distance from the point B to the hinge point of the rear upright post and the top beam is known as L 2 Takes A, B two points as the origin and L 1 And L 2 Making two circles for the radius; two circles and straight line l are respectively combined b Is defined by the equation:
solving the two sets of equations, the point with smaller abscissa is rejected in equation (1), and the point with larger abscissa is rejected in equation (2). Finally, the coordinates of the hinging points F and G of the front upright post and the rear upright post with the top beam in a Cartesian coordinate system are obtained: (x) 1 ，y 1 )，(x 2 ，y 2 )。
Further, a line parallel to the straight line l is made e Through the origin of the line:
l e1 :y＝k e x
the distance between two points of the axes of the front and rear upright posts on the height of the laser radar axis is L 3 Taking an origin as a circle center, L 3 For making a circle with radius, the circle O and the straight line l are combined e1 Is defined by the equation:
solving the equation set (3), and discarding the point with smaller abscissa to obtain a point H (x) with the same height on the rear upright post as the laser radar axis from the base 3 ，y 3 )。
Further, the linear equation of the front and rear upright posts is determined by the coordinates of the points O, F, G and H:
further, from straight line l a 、l b 、l c 、l d 、l e 、l OF 、l GH The attitude of the support shield hydraulic support can be calculated by the equation of (2).
Claims (4)
1. A support shield type hydraulic support posture intelligent monitoring system is characterized in that: the intelligent monitoring system for the posture of the supporting shield type hydraulic support comprises an intelligent monitoring device and an upper computer; the intelligent monitoring device is mining explosion-proof electrical equipment and comprises a two-dimensional laser radar, a 3-axis inclination sensor and a measurement and control host, wherein the measurement and control host and the 3-axis inclination sensor are fixed in a shell of the intelligent monitoring device, and the two-dimensional laser radar is fixed outside the shell; the intelligent monitoring device is fixedly arranged on the steel plate of the base of the supporting shield type hydraulic support and is positioned between the two front upright posts; the measurement and control host computer supplies power, controls, receives data and processes the data to the laser radar and the dip angle sensor through the cable, and transmits the resolving result to the upper computer;
the measuring method of the intelligent support shield type hydraulic support posture monitoring system comprises the following steps:
firstly, the intelligent monitoring system for the posture of the support shield type hydraulic support is divided into two working modes of timing and manual operation;
when the intelligent monitoring device is in the timing mode, the intelligent monitoring device wakes up the monitoring mode at regular time, and automatically enters a standby mode after one-time measurement is completed;
in a manual mode, a worker starts the intelligent monitoring device to start monitoring work according to requirements on an upper computer operation interface;
in the two working modes, the 3-axis inclination angle sensor is always in a working state, and when the inclination angle change output by the 3-axis inclination angle sensor is larger than a set threshold value, the intelligent monitoring device automatically starts a monitoring mode and uploads a measurement result to the upper computer;
secondly, taking the rotation axis of the laser radar as an origin, establishing a coordinate axis, and obtaining a linear equation of the base according to the inclination angle output by the 3-axis inclination sensor and the distance from the axis of the laser radar to the base, wherein the linear equation is expressed as:
l e :y＝k e x+m e
further, when the intelligent monitoring device starts monitoring, the measurement and control host controls the laser radar to rapidly rotate along the vertical direction, 180-degree rapid ranging scanning is performed, after one scanning is completed, the laser radar outputs a group of point cloud data, the distance from a discrete point of laser irradiation to each surface in the hydraulic support to a measurement starting point and a rotation included angle are represented as (r) i ，α i )(i＝1,2,3，...，n)；
Further, the horizontal inclination angle of the hydraulic support measured and output by the 3-axis inclination angle sensor is alpha 0 The point cloud data output by the radar is corrected to (r) i ，α i -α 0 ) (i=1, 2,3,.., n.), performing Hough transform and kalman filter treatment on the solution to extract 4 optimal straight lines, and corresponding to straight line equations of a side protection plate, a top beam, a shield beam and a front connecting rod of the shield hydraulic support in a laser scanning space plane, wherein the straight line equations are respectively expressed as:
l a :y＝k a x+m a
l b :y＝k b x+m b
l c :y＝k c x+m c
l d :y＝k d x+m d
further, the coordinates of the intersection A, C, D, E of the straight lines a and b, b and c, c and d, d and e in space are respectively:
A：
C：/>
D：
E：/>
further, according to the lengths of the top beam and the A, C points, the telescopic length of the front beam is obtained:
L AB ＝L AC -L BC
wherein:
further, the distance from the point A to the hinge point of the front upright post and the top beam is L 1 The distance from the point B to the hinge point of the rear upright post and the top beam is known as L 2 Takes A, B two points as the origin and L 1 And L 2 Making two circles for the radius; two circles and straight line l are respectively combined b Is defined by the equation:
solving two sets of equations, discarding the point with smaller abscissa in the equation (1) and discarding the point with larger abscissa in the equation (2); finally, the coordinates of the hinging points F and G of the front upright post, the rear upright post and the top beam in a rectangular coordinate system are obtained: (x) 1 ，y 1 )，(x 2 ，y 2 )；
Further, a line parallel to the straight line l is made e Through the origin of the line:
l e1 ：y＝k e x
the distance between two points of the axes of the front and rear upright posts on the height of the laser radar axis is L 3 Taking an origin as a circle center, L 3 For making a circle with radius, the circle O and the straight line l are combined e1 Is defined by the equation:
solving the equation set (3), and discarding the point with smaller abscissa to obtain a point H (x) with the same height on the rear upright post as the laser radar axis from the base 3 ，y 3 )；
Further, the linear equation of the front and rear upright posts is determined by the coordinates of the points O, F, G and H as follows:
l OF ：
l GH ：
so far, the calculation of the postures of all the moving components of the hydraulic support is realized.
2. The intelligent support shield hydraulic support posture monitoring system of claim 1, wherein: during measurement, the intelligent monitoring device is fixedly arranged on the plane of the base steel plate of the hydraulic support and is positioned between the two front upright posts, and the installation position is such that the axle center of the two-dimensional laser radar of the intelligent monitoring device and the axle centers of the two front upright posts are positioned on the same plane.
3. The intelligent support shield hydraulic support posture monitoring system of claim 1, wherein: the two-dimensional laser radar is fixedly arranged outside the shell of the intelligent monitoring device, and the measurement and control host controls the laser radar to rotate 180 degrees in the vertical direction in the space above the device in the supporting shield type hydraulic support during measurement, so as to perform ranging scanning.
4. The intelligent support shield hydraulic support posture monitoring system of claim 1, wherein: the intelligent monitoring device is characterized in that a measurement and control host inside the shell of the intelligent monitoring device is connected with the laser radar outside the shell through a cable and supplies power, controls and communicates the laser radar, and the measurement and control host processes data scanned and output by the laser radar to obtain an attitude resolving result and transmits the attitude resolving result to an upper computer.
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| CN114111699B (en) * | 2021-11-19 | 2022-09-09 | 山东科技大学 | Supporting posture monitoring and controlling method for supporting type hydraulic support |
| CN114217564A (en) * | 2022-02-23 | 2022-03-22 | 中国电子科技集团公司第二十八研究所 | Multifunctional GSM reconnaissance monitoring system |
| CN115371597B (en) * | 2022-09-13 | 2023-08-04 | 山东科技大学 | Method for checking position accuracy of hydraulic support base of working face |
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