Calibration method of orthogonal motion detection device

Abstract

The invention provides a calibration method of an orthogonal motion detection device, relates to the technical field of detection device calibration, and comprises an application field calibration method and a manufacturing factory calibration method. Field calibration: fixing the detection device in an application field by using a mounting bracket, and calibrating by using a field calibration tool; and after dismounting, the center hole of the sliding rod joint is connected with a measured object, the real-time coordinate of the center hole of the sliding rod joint is calculated in the established rectangular coordinate system based on the calibration parameters, and the change of the coordinate value of the real-time coordinate is the change of the position of the measured object. Manufacturing factory calibration: fixing the detection device by using a manufacturing factory calibration tool with an anti-rotation structure and performing calibration; the detection device is dismounted, the detection device is installed on an application site through the installation support, and the center hole of the sliding rod connector is connected with a measured object for measurement. The calibration method of the detection device is provided, a solution is provided for separation of a calibration place and an application place, and secondary positioning errors are effectively reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of detection device calibration, and in particular to a calibration method for an orthogonal motion detection device. Background Art

[0002] There is a demand for monitoring the movement of the point rail and the heart rail, as well as the parameters and status of the close contact with the base rail or wing rail or wing rail at the application site. At present, some monitoring methods and equipment have been proposed. Among them, Dalian University of Technology and Xi'an Railway Signal Co., Ltd. have respectively proposed to convert the movement of the point rail into a composite movement of rotation and sliding, and calculate the projection of the point rail along the direction of the straight base rail or wing rail and in the orthogonal direction perpendicular to the direction of the straight base rail or wing rail based on the detected rotation parameters and sliding parameters, that is, the movement of the point rail is equivalent to the composite movement of the predetermined orthogonal direction.

[0003] In the prior art, Dalian University of Technology proposed a calculation method for a real-time measurement device for the longitudinal creep and close gap of the point rail, with the invention patent application number CN201910630367.4. Specifically, calibration is first performed, and the calibration model is constructed based on the cosine theorem and the search method. According to the displacement data obtained from the two calibration positions, an equation is established with only the eccentricity a between the axis of the action guide rod and the axis of the rotating shaft as the unknown parameter. The design value a0 of the eccentricity is used as the initial value, and the theoretical value a of the eccentricity that meets the accuracy requirements can be obtained through continuous optimization by the search method, and then the calculation can be started.

[0004] Xi'an Railway Signal Co., Ltd. has developed a device for converting orthogonal compound motion into sliding and rotating and a motion parameter detection device, which converts the motion of the point rail or the center rail into a compound motion of rotation and linear motion and realizes the detection output of the rotation angle and linear displacement. The invention patent application number is CN202311488340.9. Specifically, the device for converting orthogonal compound motion into sliding and rotating includes a base, a bearing is fixed inside the base, and a rotating shaft is arranged inside the bearing; the bottom of the rotating shaft extends to the outside of the base, and the part located outside the base is penetrated by a transverse hole in the horizontal direction, and a sliding rod for horizontal sliding is arranged inside the transverse hole through a sliding assembly; one end of the sliding rod is connected to a joint bearing, and the joint bearing hole is connected to the measured object; a groove is opened at the bottom of the rotating shaft in the vertical direction to divide the transverse hole into two sections, and an anti-rotation block abutting against the sliding rod is fixed in the groove; when the measured object performs horizontal orthogonal compound motion, the orthogonal compound motion of the measured object is converted into the sliding of the sliding rod in the transverse hole and the rotation of the rotating shaft through the joint bearing. The detection device includes a magnetic grid for detecting the sliding displacement of the sliding rod in the transverse hole and a magnetic column for detecting the rotation angle of the rotating shaft; the magnetic grid is fixedly set on the sliding rod, and the magnetic grid is parallel to the axis of the transverse hole. The device is also provided with a first sensor aligned with the magnetic grid, and the first sensor is used to detect the sliding displacement of the magnetic grid; the magnetic column is fixedly set on the axis of the rotating shaft, and a second sensor opposite to it is fixedly set above it, and the second sensor is used to detect the rotation angle of the magnetic column. The orthogonal motion parameters of the measured object are calculated by the rotation angle of the magnetic column and the sliding displacement of the magnetic grid. In addition, the company has proposed a method suitable for detecting the orthogonal displacement of orthogonal composite moving objects. The displacement of the point rail or the center rail on the orthogonal axis is calculated by the detected rotation angle and linear displacement data. The invention patent application number is 202310779837.X.

[0005] The above calculation methods are all calibrated before starting continuous measurement. The calibration models are all based on the cosine theorem to calculate the required parameters, and then the orthogonal displacement calculation is performed according to the calculated parameters. During the parameter calculation process, the distance from the initial point to the origin of the coordinate system is constructed using the cosine theorem to form a quadratic equation. After solving it, the correct solution is determined and selected.

[0006] However, solving a quadratic equation involves square root calculations, which limits software programming. The correct solution may be selected incorrectly, resulting in errors in subsequent measurement and calculation results. Secondly, due to the secondary positioning error in calibration and installation, whether the calibration parameters can be correctly transferred to the use state is related to the measurement method, calculation method, and fixed installation method. The measurement method is determined by the selected sensor. Sensors include absolute value sensors and relative value sensors. Relative value sensors may cause deviations in the calibration benchmark and measurement benchmark. If the calibration and calculation methods are closely related to the fixed position of the detection device, the secondary positioning error may also cause obvious result deviations. Summary of the invention

[0007] To solve the above problems, the present invention provides a calibration method for an orthogonal motion detection device. The present invention provides a calibration method for a detection device based on a prior application, provides a solution for separating the calibration site and the application site, can perform calibration quickly, and effectively reduce secondary positioning errors.

[0008] To achieve the above object, the present invention provides the following technical solutions.

[0009] The invention provides a calibration method for an orthogonal motion detection device, including an application site calibration method and a manufacturing plant calibration method.

[0010] The on-site calibration method includes the following steps:

[0011] The detection device is fixedly installed on the measurement reference using a mounting bracket;

[0012] The on-site calibration tool is installed and fixed in an appropriate position, relatively fixed to the measurement reference; the on-site calibration tool comprises a calibration fixing component and a calibration plate; the calibration fixing component is used to fix the calibration plate, and the calibration plate has at least two calibration points, and the connection direction of the calibration points is perpendicular or parallel to the measurement focus direction or maintains a specified angle;

[0013] The sliding rod in the detection device is retracted to the limit position, the detection device is powered on, the two sensors work, the sliding rod is extended, and the center hole of the sliding rod joint is connected to the two calibration points respectively, and the displacement of the center hole of the sliding rod joint from the limit position to the two calibration points and the two rotation angles measured by the rotation angle sensor are obtained respectively through the two sensors;

[0014] Construct a rectangular coordinate system with the axis of the angle sensor as the origin and the direction of interest as the coordinate axis. According to the displacement of the center hole of the sliding rod joint from the extreme position to the two calibration points and the two angles, obtain the distance from the center hole of the sliding rod joint to the origin and the angle between the zero angle of the angle sensor and the coordinate axis when the sliding rod is at the extreme position as calibration parameters to complete the calibration.

[0015] Remove the on-site calibration tooling, connect the center hole of the sliding rod joint to the object to be measured, calculate the real-time coordinates of the center hole of the sliding rod joint in the established rectangular coordinate system, and the change in the coordinate value of the real-time coordinate is the measured value of the position change of the object to be measured.

[0016] The manufacturing plant calibration method includes the following steps:

[0017] The detection device and the mounting bracket have mutually cooperating anti-rotation structures so that the detection device and the mounting bracket can only be installed in a fixed relative position. The calibration tooling in the manufacturing plant has the same anti-rotation structure and detection device fixed installation structure as the mounting bracket, and has at least two calibration points. With the installed fixed detection device as a reference, the connection direction of the calibration points is parallel or perpendicular to the direction of interest at the expected application site, or at a specified angle.

[0018] The detection device is fixedly installed on the calibration tooling of the manufacturing plant, the sliding rod in the detection device is retracted to the limit position, the detection device is powered on, the two sensors work, the sliding rod is extended, and the center hole of the sliding rod joint is connected to the two calibration points respectively, and the displacement of the center hole of the sliding rod joint from the limit position to the two calibration points and the two rotation angles measured by the rotation angle sensor are respectively obtained through the two sensors;

[0019] Construct a rectangular coordinate system with the axis of the angle sensor as the origin and the direction of interest as the coordinate axis. According to the displacement of the center hole of the sliding rod joint from the extreme position to the two calibration points and the two angles, obtain the distance from the center hole of the sliding rod joint to the origin and the angle between the zero angle of the angle sensor and the coordinate axis when the sliding rod is at the extreme position as calibration parameters to complete the calibration.

[0020] The detection device is removed from the calibration tooling in the manufacturing plant, and fixedly installed on the mounting bracket at the installation application site. The sliding rod in the detection device is retracted to the limit position, the detection device is powered on, the two sensors work, the center hole of the sliding rod joint is connected to the object to be measured, and the real-time coordinates of the center hole of the sliding rod joint are calculated in the established rectangular coordinate system. The change in the coordinate value of the real-time coordinate is the measured value of the position change of the object to be measured.

[0021] Preferably, the object to be measured is a point rail or a center rail of a turnout;

[0022] When the calibration is performed on site, the detection device is fixedly installed on the outside of the base rail or wing rail by means of the mounting bracket, and the field calibration tool is installed and fixed on the base rail or wing rail during the calibration process to perform field calibration; after the calibration, the field calibration tool is removed, the center hole of the sliding rod joint is connected to the measured point rail or heart rail, and the displacement of the measured heart rail or point rail is determined according to the calibration parameters;

[0023] When the manufacturing plant performs calibration, the manufacturing plant calibration tooling with an anti-rotation structure is used to fix the detection device and perform calibration; after calibration, the detection device is installed on the base rail or wing rail through a mounting bracket with the same anti-rotation structure, and the center hole of the sliding rod joint is connected to the point rail or heart rail to be measured to measure the position change.

[0024] Preferably, the calculation of the distance from the center hole of the sliding rod joint to the coordinate origin and the angle between the zero angle of the rotation angle sensor and the coordinate axis when the sliding rod is at the extreme position according to the calibration algorithm comprises the following steps:

[0025] Construct a coordinate system with the direction of the basic rail or wing rail as the X-axis, the rotation center of the detection device as the coordinate origin, and the direction perpendicular to the basic rail or wing rail as the Y-axis. The direction of the line connecting the two calibration points is parallel to the coordinate axis X-axis. Then the Y coordinates of the two calibration points are equal in the calibrated and solved coordinate system, and the difference in the X coordinates is equal to the distance between the two calibration points.

[0026] The rotation center of the detection device is set to O. The distance from the rotation center O of the detection device to the center hole of the sliding rod joint is R when the sliding rod is in the retracted limit position. The calibration points are A and B, and the distance is m. When the center hole of the sliding rod joint moves to A and B, the displacements relative to the retracted limit position are L1 and L2, respectively. The angle values ​​measured by the angle sensor are α1 and α2, respectively. Then, if the angle zero position of the angle sensor is OP and is located between the X-axis and OB, then ∠POA=α1, ∠POB=α1, and the angle between the angle zero position of the angle sensor and the direction of the basic rail or wing rail is the angle β between OP and the X-axis;

[0027] According to the law of sines:

[0028] (L1+R) / sin(β+α2)=m / sin(α1-α2)=(L2+R) / sin(180°-(β+α1))

[0029] That is:

[0030] m*sin(β+α2)=(L1+R)*sin(α1-α2)

[0031] m*sin(180°-(β+α1))=(L2+R)*sin(α1-α2)

[0032] According to the projection relationship between OA and OB on the X-axis and Y-axis, we have:

[0033] (L2+R)*sin(β+α2)=(L1+R)*sin(β+α1)

[0034] (L2+R)*cos(β+α2)=m+(L1+R)*cos(β+α1)

[0035] In addition:

[0036] sin(β+α2)=sinβcos(α2)+cosβsin(α2)

[0037] sin(β+α1)=sinβcos(α1)+cosβsin(α1)

[0038] cos(β+α2)=cosβcos(α2)-sinβsin(α2)

[0039] cos(β+α1)=cosβcos(α1)-sinβsin(α1)

[0040] but:

[0041] m*sin(180°-(β+α1))=(L2+R)*sin(α1-α2)

[0042] m*sin(β+α2)=(L1+R)*sin(α1-α2)

[0043] Subtracting both sides of the equal sign, we get:

[0044] m*(sin(β+α1)-sin(β+α2))=(L2-L1)*sin(α1-α2)

[0045] but:

[0046] m*(2cos((2*β+α1+α2) / 2)sin((α1-α2) / 2)=(L2-L1)*sin(α1-α2)cos((2*β+α1+α2) / 2)=(L2-L1)*sin(α1-α2) / (2*m*sin((α1-α2) / 2))

[0047] but:

[0048] β+(α1+α2) / 2=2kπ±arccos((L2-L1)*sin(α1-α2)) / (2*m*sin((α1-α2) / 2)))

[0049] Then, the calculation formula of the angle β between the angle zero position of the angle sensor and the direction of the basic track or wing track is: β=2kπ±arccos((L2-L1)*sin(α1-α2) / (2*m*sin((α1-α2) / 2)))-(α1+α2) / 2, where 0°≤β≤90°;

[0050] The calculation formula for R is obtained according to m*sin(β+α2)=(L1+R)*sin(α1-α2) or m*sin(180°-(β+α1))=(L2+R)*sin(α1-α2).

[0051] Preferably, the calculation of the distance from the center hole of the sliding rod joint to the coordinate origin and the angle between the zero angle of the rotation angle sensor and the coordinate axis when the sliding rod is at the extreme position according to the calibration algorithm comprises the following steps:

[0052] Construct a coordinate system with the direction of the basic rail or wing rail as the X-axis, the rotation center of the detection device as the coordinate origin, and the direction perpendicular to the basic rail or wing rail as the Y-axis. The Y coordinates of the two calibration points are equal in the calibrated and solved coordinate system, and the difference in the X coordinates is equal to the distance between the two calibration points;

[0053] The rotation center of the detection device is set to O. The distance from the rotation center O of the detection device to the center hole of the sliding rod joint is R when the sliding rod is at the retracted limit position. The calibration points are A and B, and the distance is m. When the center hole of the sliding rod joint moves to A and B, the displacements relative to the retracted limit are L1 and L2, respectively. The angle values ​​measured by the angle sensor are α1 and α2, respectively. Then, if the angle zero position of the angle sensor is OP and is located between the X-axis and OB, then ∠POA=α1, ∠POB=α1, and the angle between the angle zero position of the angle sensor and the direction of the basic rail or wing rail is the angle β between OP and the X-axis;

[0054] Construct a circle with OA as diameter and determine that the intersection of this circle and OB is C; in triangle ABC, ∠BAC = ∠a, ∠ACB = ∠c and ∠ABC = ∠b;

[0055] Using the law of sines we have:

[0056]

[0057] Then, the three interior angles of the triangle are:

[0058] ∠b=α2+β

[0059]

[0060] Substituting into the sine formula we get:

[0061]

[0062] According to the trigonometric function formula sin(90°+α)=cosα, sin(90°-α)=cosα, the formula changes to:

[0063]

[0064] Wherein, 0°≤β≤90°; the calculation formula of the angle β between the zero position of the angle sensor and the direction of the basic rail or wing rail is obtained from the above formula;

[0065] The calculation formula for R is obtained according to m*sin(β+α2)=(L1+R)*sin(α1-α2) or m*sin(180°-(β+α1))=(L2+R)*sin(α1-α2).

[0066] Preferably, if the angle zero position OP of the angle sensor is not between the X-axis and OB, the angle zero position of the angle sensor is rotated to meet the requirements, and physical angle rotation or numerical compensation is performed; wherein, the numerical compensation method is to subtract the angle value required to be rotated from the output angle of the angle sensor, and the angle sensor is powered on again after being powered off. If the rotated angle zero position cannot be maintained, the angle of the angle zero position needs to be recorded in the software, and in subsequent calculations, the angle β between the angle zero position of the angle sensor and the basic track or wing track direction needs to be used as a calculation parameter at the same time.

[0067] Preferably, the on-site calibration tool is installed and fixed on the basic rail or wing rail during the calibration process; the on-site calibration tool includes a hook head assembly and a calibration plate; the hook head assembly is clamped to the basic rail or wing rail, and the calibration plate is located on the other side of the basic rail or wing rail; the hook head assembly includes a calibration hook head, a hook head bolt and a nut; when in use, the calibration hook head and the hook head parts of the hook head bolt are respectively close to the two sides and the bottom of the basic rail or wing rail, the bolt part of the hook head bolt passes through the calibration hook head, and the end of the bolt part of the hook head bolt is fixed to the calibration hook head through the nut; the calibration plate is an L-shaped or T-shaped component; one side of the calibration plate is detachably fixed to the calibration hook head, and the other side is provided with calibration points, and the connection direction of the calibration points is parallel to the extension direction of the basic rail or wing rail.

[0068] Preferably, the base of the detection device is provided with an anti-rotation structure, which cooperates with the mounting bracket to prevent the detection device from rotating relative to the mounting bracket, and includes an anti-rotation slot or a positioning pin.

[0069] Preferably, the mounting bracket includes a mounting hook head and a mounting hook head bolt; when in use, the mounting hook head and the hook head parts of the mounting hook head bolt are respectively close to the two sides and the rail bottom of the basic rail or the wing rail, the bolt part of the mounting hook head bolt passes through the mounting hook head, and the end of the bolt part of the mounting hook head bolt is fixed to the mounting hook head by a nut; the mounting hook head is extended outward with a mounting plate; the mounting plate is provided with a mounting hole for fixing the detection device.

[0070] Preferably, the calibration tool includes a limit sleeve for limiting the sliding rod to be retracted to the extreme position. During the calibration process and on-site restoration process, when the sliding rod needs to be retracted to the extreme position, the limit sleeve is clamped on the outer periphery of the sliding rod, and the limit sleeve is removed after completion.

[0071] Beneficial effects of the present invention:

[0072] The present invention proposes a calibration method for an orthogonal motion detection device, which is applicable to two scenarios. The first is on-site calibration, which uses an on-site calibration tool to realize calibration after the detection device is installed on-site. After installation, the angles of the rotating shaft and the fixed part of the detection device relative to the base rail or the wing rail are fixed. These parameters are calculated through calibration to avoid secondary positioning errors. The second is calibration in a laboratory or manufacturing plant using a manufacturing plant calibration tool. The tool has a fixed installation structure for the detection device and has the same anti-rotation structure as the mounting bracket of the detection device. After the calibration is completed, the mounting bracket can be used to restore to the same fixed angle during calibration at the application site, and the sliding rod can be restored to the retracted limit position. In this way, the calibration state can be restored on-site after calibration in the laboratory, avoiding calibration under harsh conditions on site and affecting the calibration accuracy, thereby shortening the on-site construction time. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] Figure 1 is a flow chart of a calibration process of an orthogonal motion detection device according to Embodiment 1 of the present invention;

[0074] Figure 2 is a relationship diagram between calibration parameters and sensor values ​​of Embodiment 1 and Embodiment 2 of the present invention;

[0075] Figure 3 is a structural schematic diagram of an on-site calibration tooling according to Embodiment 1 of the present invention;

[0076] Figure 4 It is a schematic diagram of calibration of the detection device of Example 1 of the present invention using an on-site calibration tool after being installed on-site;

[0077] Figure 5 It is a schematic diagram of the assembly of the anti-rotation slot and the anti-rotation socket between the base of the detection device and the mounting bracket in Example 1 of the present invention;

[0078] Figure 6 is a schematic diagram of the detection device of Example 1 of the present invention being calibrated using the calibration tool of the manufacturing factory;

[0079] Figure 7 is a relationship diagram between calibration parameters and sensor values ​​when the angle zero position of embodiment 3 of the present invention is located between the coordinate origin and the line connecting the two calibration points;

[0080] Figure 8 is a relationship diagram between the calibration parameters and the sensor values ​​when the coordinate origin and the connecting line between the two calibration points in Example 3 of the present invention are between the angle zero position and the positive direction of the X-axis;

[0081] Fig. 9 This is a schematic diagram of the mounting bracket of the anti-rotation bayonet.

[0082] In the figure: 1. Detection device; 1-1. Anti-rotation structure on the base of the detection device; 2. Mounting bracket; 2-1. Mounting hook; 2-2. Mounting hook bolt; 3. Sliding rod; 4. On-site calibration tooling; 4-1. Calibration plate; 4-2. Calibration hook; 4-3. Hook bolt; 4-4. Nut; 5. Calibration tooling at the manufacturing plant; 5-1. Anti-rotation structure on the calibration tooling at the manufacturing plant. DETAILED DESCRIPTION

[0083] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0084] Example 1

[0085] Since there are secondary positioning errors in calibration and installation, whether the calibration parameters can be correctly transmitted to the use state is related to the measurement method, calculation method, and fixed installation method. The measurement method is determined by the selected sensor. The sensor includes absolute value sensors and relative value sensors. The relative value sensor may cause deviations in the calibration benchmark and the measurement benchmark. If the calibration and calculation methods are closely related to the fixed position of the detection device, the secondary positioning error may also cause obvious result deviations. If the calibration is performed after the detection equipment is fixedly installed, and then the measurement and detection state is directly entered, there will be no secondary positioning error, and there will be no influence of the zero position change of the relative value sensor. In theory, a relatively ideal result can be obtained, but in actual operation, there are still difficulties that are difficult to overcome. For example, on-site calibration is inconvenient, the operation is difficult, and the calibration accuracy is poor, which affects the accuracy of subsequent measurements. To this end, a calibration method for an orthogonal motion detection device of the present invention is provided. The specific process is as follows: Figure 1 As shown, the calibration object in this embodiment, that is, the detection device, has the same structure and working principle as the previously applied Chinese patent CN202311488340.9. This embodiment specifically includes the following steps:

[0086] S1: Use a mounting bracket to fix the detection device 1 on the outside of the base rail or the wing rail.

[0087] S2: The on-site calibration tool 4 is fixedly set on the basic rail or the wing rail; the on-site calibration tool 4 includes a hook head assembly and a calibration plate 4-1; the hook head assembly is clamped to the basic rail or the wing rail, and the calibration plate 4-1 is located on the other side of the basic rail or the wing rail; the calibration plate 4-1 has at least two calibration points, and the connection direction of the calibration points is parallel to the extension direction of the basic rail or the wing rail.

[0088] S3: Retract the sliding rod 3 in the detection device 1 to the extreme position, power on the detection device 1, work the two sensors, extend the sliding rod 3, connect the ends of the sliding rod 3 to the two calibration points respectively, and obtain the displacement of the ends of the sliding rod 3 from the extreme position to the two calibration points and the two angles measured by the angle sensor through the two sensors.

[0089] S4: Construct a rectangular coordinate system with the axis of the angle sensor as the coordinate origin and the directions parallel to the basic rail or wing rail and perpendicular to the basic rail or wing rail as the coordinate axes. According to the displacement of the end of the sliding rod 3 from the extreme position to the two calibration points and the two angles, obtain the distance from the end of the sliding rod 3 to the coordinate origin and the angle between the zero angle of the angle sensor and the coordinate axis when the sliding rod 3 is at the extreme position as calibration parameters to complete the calibration.

[0090] S5: Remove the on-site calibration tooling, connect the end of the sliding rod 3 to the measured point rail or center rail, calculate the real-time coordinates of the end of the sliding rod 3 in the established rectangular coordinate system, and the change in the coordinate value of the real-time coordinates is the change in the position of the measured point rail or center rail.

[0091] When calibrating directly on site, the on-site calibration tool 4 is used. The structural diagram of the on-site calibration tool is as follows: Figure 3 As shown, the on-site calibration tool 4 includes a hook head assembly and a calibration plate 4-1, and the hook head assembly includes a calibration hook head 4-2, a hook head bolt 4-3 and a nut 4-4; when in use, the calibration hook head 4-1 and the hook head parts of the hook head bolt 4-3 are respectively close to the two sides and the bottom of the basic rail or the wing rail, the bolt part of the hook head bolt 4-3 passes through the calibration hook head 4-2, and the end of the bolt part of the hook head bolt 4-3 is fixed to the calibration hook head 4-2 by the nut 4-4; the calibration plate 4-1 is an L-shaped component; one side of the calibration plate 4-1 is detachably fixed to the calibration hook head 4-2, and the other side is provided with calibration points, and the connection direction of the calibration points is parallel to the extension direction of the basic rail or the wing rail; a fixing plate is provided on one side of the calibration plate 4-1, and a fixing hole for fixing the detection device 1 is provided on the fixing plate.

[0092] like Figure 4 As shown, the mounting bracket 2 includes a mounting hook head 2-1 and a mounting hook head bolt 2-2; when in use, the mounting hook head 2-1 and the hook head parts of the mounting hook head bolt 2-2 are respectively pressed against both sides and the bottom of the basic rail or the wing rail, the bolt part of the mounting hook head bolt 2-2 passes through the mounting hook head 2-1, and the end of the bolt part of the mounting hook head bolt 2-2 is fixed to the mounting hook head 2-1 by a nut; a mounting plate is extended outward from the mounting hook head 2-1; a mounting hole for fixing the detection device 1 is provided on the mounting plate.

[0093] In order to reduce the workload and working hours under harsh conditions on site, the calibration work can be carried out at the manufacturing plant and the calibration status can be restored at the installation site, including the following steps:

[0094] S1: The detection device 1 and the mounting bracket 2 have mutually cooperating anti-rotation structures so that the detection device 1 and the mounting bracket 2 can only be installed in a fixed relative position. The manufacturing plant calibration tooling has the same anti-rotation structure as the mounting bracket and the fixed mounting structure of the detection device 1, and has at least two calibration points. With the detection device 1 as a reference, the connection direction of the calibration points is parallel to the extension direction of the basic rail or wing rail at the expected application site. The assembly status of the anti-rotation structure 1-1 on the base of the detection device and the anti-rotation structure 5-1 on the manufacturing plant calibration tooling is as follows: Figure 6 shown.

[0095] S2: Fix the detection device 1 on the calibration tool 4 of the manufacturing plant, retract the sliding rod 3 in the detection device 1 to the extreme position, power on the detection device 1, work the two sensors, extend the sliding rod 3, and connect the ends of the sliding rod 3 to the two calibration points respectively. The displacement of the end of the sliding rod 3 from the extreme position to the two calibration points and the two angles measured by the angle sensor are obtained through the two sensors.

[0096] S3: Construct a rectangular coordinate system with the axis of the angle sensor as the coordinate origin and the directions parallel to the basic rail or wing rail and perpendicular to the basic rail or wing rail as the coordinate axes. According to the displacement of the end of the sliding rod 3 from the extreme position to the two calibration points and the two angles, obtain the distance from the end of the sliding rod 3 to the coordinate origin and the angle between the zero angle of the angle sensor and the coordinate axis when the sliding rod 3 is in the extreme position as calibration parameters to complete the calibration.

[0097] S4: Remove the detection device 1 from the calibration tooling 4 in the manufacturing plant, and fix it on the mounting bracket 2 at the installation application site. Retract the sliding rod 3 in the detection device 1 to the extreme position, power on the detection device 1, and work with the two sensors. Connect the end of the sliding rod 3 to the point rail or heart rail to be measured, and calculate the real-time coordinates of the center hole of the sliding rod joint in the established rectangular coordinate system. The change in the coordinate value of the real-time coordinate is the change in the position of the point rail or heart rail to be measured.

[0098] Specifically, an anti-rotation slot is provided on the mounting base of the detection device 1, an anti-rotation socket corresponding to the anti-rotation slot is designed on the calibration tooling of the manufacturing factory, and an anti-rotation socket corresponding to the anti-rotation slot of the detection device 1 is also provided on the mounting bracket. After the anti-rotation slot is inserted into the anti-rotation socket, the shell of the detection device 1 cannot rotate. The schematic diagram of the assembly state of the anti-rotation structure 1-1 on the base of the detection device and the anti-rotation structure 5-1 on the calibration tooling of the manufacturing factory is shown in FIG. Figure 5 and Figure 6As shown, there are at least two calibration points and fixing holes of the detection device 1 on the calibration tooling of the manufacturing plant, the connection line of the calibration points and the anti-rotation socket have a fixed angle (such as vertical or parallel), the anti-rotation slot of the detection device 1 is clamped with the anti-rotation socket of the calibration tooling of the manufacturing plant and the fastening hole is used to fix the detection device 1 on the calibration tooling of the manufacturing plant so that it cannot move relative to each other, so that the sliding rod of the detection device 1 is respectively connected to the calibration points of appropriate number and position, the detection device 1 is powered on and works when the sliding rod is retracted to the extreme position, the calibration parameters are calculated according to the sensor values ​​of the detection device 1, and the calibration parameters of the angle sensor and the calibration parameters of the linear displacement sensor are obtained. After the calibration is completed, the detection device 1 can be installed and operated on site. After the mounting bracket 2 is fixed on the base rail or wing rail, the anti-rotation slot of the detection device 1 is clamped with the anti-rotation bayonet of the mounting bracket 2 and the detection device 1 is fixed on the mounting bracket 2. Then, for the angle sensor, the installation angle of the detection device 1 on the calibration tool 4 in the manufacturing plant and on the mounting bracket 2 relative to the coordinate axis are the same or the deviation is a preset fixed value. Retract the sliding rod 3 to the extreme position or use a limit sleeve to limit the extreme position, then power on the detection device 1 to start working, and connect the sliding rod 3 to the object to be measured to measure the coordinate value of the object to be measured in the constructed coordinate system in real time. The schematic diagram of the mounting bracket of the anti-rotation bayonet is shown in the figure. Fig. 9 shown.

[0099] The manufacturing plant calibration tool has a fixed installation structure of the detection device 1, and has a bayonet that matches the slot on the detection device 1. The slot of the detection device 1 is fixed with the fixed installation structure after being matched with the bayonet. At least two calibration points are set on the manufacturing plant calibration tool. The angle between the connection line of the calibration point and the specified part of the detection device 1 is the same as the angle between the specified part and the extension direction of the basic rail or wing rail after the detection device 1 is fixedly installed on the mounting bracket, or the deviation is a preset fixed value. The calibration point is usually a hole with a fixed diameter, which is connected with the center hole of the sliding rod joint of the detection device using a connecting pin. The detection device 1 outputs the sensor detection value corresponding to the calibration point. According to the calibration algorithm, the calibration parameters can be calculated using appropriate calibration points.

[0100] Specifically, the relationship between the calibration parameters in S3 and S4 and the values ​​measured by the sensor is shown in the figure below: Figure 2 As shown, the calculation process of the calibration parameters includes the following steps:

[0101] Construct a coordinate system with the basic rail or wing rail direction as the X-axis, the rotation center of the detection device as the coordinate origin, and the Y-axis perpendicular to the basic rail or wing rail. The direction of the line connecting the two calibration points is parallel to the coordinate axis X-axis. Then the Y coordinates of the two calibration points are equal in the calibrated and solved coordinate system, and the difference in X coordinates is equal to the distance between the two calibration points; the rotation center of the detection device is set to O, and the distance from the rotation center O of the detection device to the center hole of the sliding rod joint is R when the sliding rod is in the retracted limit position. The calibration points are A and B, respectively, and the distance is m. When the center hole of the sliding rod joint moves to A and B, the displacement relative to the retracted limit position is L1 and L2, respectively. The angle values ​​measured by the angle sensor are α1 and α2, respectively. Then, if the angle zero position of the angle sensor is OP and is located between the X-axis and OB, then ∠POA=α1, ∠POB=α1, and the angle between the angle zero position of the angle sensor and the basic rail or wing rail direction is the angle β between OP and the X-axis;

[0102] According to the law of sines:

[0103] (L1+R) / sin(β+α2)=m / sin(α1-α2)=(L2+R) / sin(180°-(β+α1))

[0104] That is:

[0105] m*sin(β+α2)=(L1+R)*sin(α1-α2)

[0106] m*sin(180°-(β+α1))=(L2+R)*sin(α1-α2)

[0107] According to the projection relationship between OA and OB on the X-axis and Y-axis, we have:

[0108] (L2+R)*sin(β+α2)=(L1+R)*sin(β+α1)

[0109] (L2+R)*cos(β+α2)=m+(L1+R)*cos(β+α1)

[0110] In addition:

[0111] sin(β+α2)=sinβcos(α2)+cosβsin(α2)

[0112] sin(β+α1)=sinβcos(α1)+cosβsin(α1)

[0113] cos(β+α2)=cosβcos(α2)-sinβsin(α2)

[0114] cos(β+α1)=cosβcos(α1)-sinβsin(α1)

[0115] but:

[0116] m*sin(180°-(β+α1))=(L2+R)*sin(α1-α2)

[0117] m*sin(β+α2)=(L1+R)*sin(α1-α2)

[0118] Subtracting both sides of the equal sign, we get:

[0119] m*(sin(β+α1)-sin(β+α2))=(L2-L1)*sin(α1-α2)

[0120] but:

[0121] m*(2cos((2*β+α1+α2) / 2)sin((α1-α2) / 2)=(L2-L1)*sin(α1-α2)cos((2*β+α1+α2) / 2)=(L2-L1)*sin(α1-α2) / (2*m*sin((α1-α2) / 2))

[0122] but:

[0123] β+(α1+α2) / 2=2kπ±arccos((L2-L1)*sin(α1-α2)) / (2*m*sin((α1-α2) / 2)))

[0124] Then, the calculation formula of the angle β between the angle zero position of the angle sensor and the direction of the basic track or wing track is: β=2kπ±arccos((L2-L1)*sin(α1-α2) / (2*m*sin((α1-α2) / 2)))-(α1+α2) / 2, where 0°≤β≤90°;

[0125] The calculation formula for R is obtained according to m*sin(β+α2)=(L1+R)*sin(α1-α2) or m*sin(180°-(β+α1))=(L2+R)*sin(α1-α2).

[0126] Among them, when the OP position and Figure 2 If it does not match, you can rotate the angle sensor to zero position to make it Figure 2There are at least three ways to rotate the position shown. The first is to physically rotate the angle of the relevant parts. The second is to achieve it through the function of the angle sensor, which is equivalent to physical realization. The third is to subtract the angle value to be rotated from the output angle of the angle sensor. If the sensor is powered off and then powered on again, the angle of the angle zero position cannot be maintained. The angle of the angle zero position must be recorded in the software, and it must be used as a calculation parameter together with β in subsequent calculations.

[0127] Example 2

[0128] The relationship between the calibration parameters in S3 and S4 and the values ​​measured by the sensor is shown in the figure below. Figure 2 As shown, the construction of the relationship between the angle zero position of the angle sensor and the angle between the direction of the base rail or the wing rail and the distance from the rotation center of the detection device to the extreme position includes the following steps:

[0129] Construct a coordinate system with the direction of the basic rail or wing rail as the X-axis, the rotation center of the detection device as the coordinate origin, and the direction perpendicular to the basic rail or wing rail as the Y-axis. The Y coordinates of the two calibration points are equal in the calibrated and solved coordinate system, and the difference in the X coordinates is equal to the distance between the two calibration points;

[0130] The rotation center of the detection device is set to O. The distance from the rotation center O of the detection device to the center hole of the sliding rod joint is R when the sliding rod is at the retracted limit position. The calibration points are A and B, and the distance is m. When the center hole of the sliding rod joint moves to A and B, the displacements relative to the retracted limit are L1 and L2, respectively. The angle values ​​measured by the angle sensor are α1 and α2, respectively. Then, if the angle zero position of the angle sensor is OP and is located between the X-axis and OB, then ∠POA=α1, ∠POB=α1, and the angle between the angle zero position of the angle sensor and the direction of the basic rail or wing rail is the angle β between OP and the X-axis;

[0131] Construct a circle with OA as diameter and determine that the intersection of this circle and OB is C; in triangle ABC, ∠BAC = ∠a, ∠ACB = ∠c and ∠ABC = ∠b;

[0132] Using the law of sines we have:

[0133]

[0134] Then, the three interior angles of the triangle are:

[0135] ∠b=α2+β

[0136]

[0137] Substituting into the sine formula we get:

[0138]

[0139] According to the trigonometric function formula sin(90°+α)=cosα, sin(90°-α)=cosα, the formula changes to:

[0140]

[0141] Wherein, 0°≤β≤90°; the calculation formula of the angle β between the zero position of the angle sensor and the direction of the basic rail or wing rail is obtained from the above formula;

[0142] The calculation formula for R is obtained according to m*sin(β+α2)=(L1+R)*sin(α1-α2) or m*sin(180°-(β+α1))=(L2+R)*sin(α1-α2).

[0143] Example 3

[0144] When the OP position and Figure 2 If not, you can follow Figure 7 or Figure 8 Or other situations are used for calibration calculation, but the principle is basically the same, that is, the angle of the sliding rod measured by the angle sensor is used to express the angle relationship between the sliding rod and the positive direction of the X-axis, the displacement value of the sliding rod is used to express the distance from the coordinate center to the center of the sliding rod joint, and then the coordinate value of the center of the sliding rod joint is calculated in a predetermined coordinate system (rectangular coordinate system or polar coordinate system).

[0145] For a detection device of the CN202310779837.X structure, the position of the center hole of the sliding rod joint can be calculated using polar coordinates and converted into rectangular coordinates in the corresponding rectangular coordinate system, which is the position of the measured part connected to the center hole of the sliding rod joint.

[0146] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A calibration method for an orthogonal motion detection device, characterized in that: The following steps are involved: Calibration of the detection device for orthogonal motion based on the application site or the manufacturing plant; wherein, when the calibration is performed on the application site, the detection device is fixedly installed at the application site using a mounting bracket, and the calibration is performed using a field calibration tool; when the calibration is performed in the manufacturing plant, the detection device is fixed and calibrated using a manufacturing plant calibration tool with an anti-rotation structure; The intersection of the detection axis of the rotation angle sensor in the detection device and the detection plane is taken as the coordinate origin, and the movement direction of interest is taken as the coordinate axis direction to form a rectangular coordinate system; the on-site calibration tooling and the manufacturing factory calibration tooling both include at least two calibration points, and the connection direction of the calibration points is parallel or perpendicular to the coordinate axis or has a preset value angle; The sliding rod in the detection device is retracted to the limit position, the detection device is powered on, the two sensors work, the sliding rod is extended, and the center hole of the sliding rod joint is connected to the two calibration points respectively, and the displacement of the center hole of the sliding rod joint from the limit position to the two calibration points and the two rotation angles measured by the rotation angle sensor are obtained respectively through the two sensors; According to the calibration algorithm, the distance from the center hole of the sliding rod joint to the coordinate origin and the angle between the zero angle of the angle sensor and the coordinate axis are calculated as calibration parameters when the sliding rod is at the extreme position to complete the calibration; When calibration is performed at the application site, the on-site calibration tooling is removed, the center hole of the sliding rod joint is connected to the object to be measured, and the real-time coordinates of the center hole of the sliding rod joint are calculated in the established rectangular coordinate system based on the calibration parameters. The change in the coordinate value of the real-time coordinate is the change in the position of the object to be measured. When calibration is performed at the manufacturing plant, the detection device is removed from the calibration tooling of the manufacturing plant, and the detection device is installed at the application site via a mounting bracket with the same anti-rotation structure, and the center hole of the sliding rod joint is connected to the object to be measured to measure the position change.

2. The calibration method of the orthogonal motion detection device according to claim 1, characterized in that: The object to be measured is a point rail or a center rail of a turnout; When the calibration is performed on site, the detection device is fixedly installed on the outside of the base rail or wing rail by means of the mounting bracket, and the field calibration tool is installed and fixed on the base rail or wing rail during the calibration process to perform field calibration; after the calibration, the field calibration tool is removed, the center hole of the sliding rod joint is connected to the measured point rail or heart rail, and the displacement of the measured heart rail or point rail is determined according to the calibration parameters; When the manufacturing plant performs calibration, the manufacturing plant calibration tooling with an anti-rotation structure is used to fix the detection device and perform calibration; after calibration, the detection device is installed on the base rail or wing rail through a mounting bracket with the same anti-rotation structure, and the center hole of the sliding rod joint is connected to the point rail or heart rail to be measured to measure the position change.

3. The calibration method of the orthogonal motion detection device according to claim 2, characterized in that: The calculation of the distance from the center hole of the sliding rod joint to the coordinate origin and the angle between the zero angle of the rotation angle sensor and the coordinate axis when the sliding rod is at the extreme position according to the calibration algorithm includes the following steps: Construct a coordinate system with the direction of the basic rail or wing rail as the X-axis, the rotation center of the detection device as the coordinate origin, and the direction perpendicular to the basic rail or wing rail as the Y-axis. The direction of the line connecting the two calibration points is parallel to the coordinate axis X-axis. Then the Y coordinates of the two calibration points are equal in the calibrated and solved coordinate system, and the difference in the X coordinates is equal to the distance between the two calibration points. The rotation center of the detection device is set to O. The distance from the rotation center O of the detection device to the center hole of the sliding rod joint is R when the sliding rod is in the retracted limit position. The calibration points are A and B, and the distance is m. When the center hole of the sliding rod joint moves to A and B, the displacements relative to the retracted limit position are L1 and L2, respectively. The angle values ​​measured by the angle sensor are α1 and α2, respectively. Then, if the angle zero position of the angle sensor is OP and is located between the X-axis and OB, then ∠POA=α1, ∠POB=α1, and the angle between the angle zero position of the angle sensor and the direction of the basic rail or wing rail is the angle β between OP and the X-axis; According to the law of sines: (L1+R) / sin(β+α2)=m / sin(α1-α2)=(L2+R) / sin(180°-(β+α1)) That is: m*sin(β+α2)=(L1+R)*sin(α1-α2) m*sin(180°-(β+α1))=(L2+R)*sin(α1-α2) According to the projection relationship between OA and OB on the X-axis and Y-axis, we have: (L2+R)*sin(β+α2)=(L1+R)*sin(β+α1) (L2+R)*cos(β+α2)=m+(L1+R)*cos(β+α1) In addition: sin(β+α2)=sinβcos(α2)+cosβsin(α2) sin(β+α1)=sinβcos(α1)+cosβsin(α1) cos(β+α2)=cosβcos(α2)-sinβsin(α2) cos(β+α1)=cosβcos(α1)-sinβsin(α1) but: m*sin(180°-(β+α1))=(L2+R)*sin(α1-α2) m*sin(β+α2)=(L1+R)*sin(α1-α2) Subtracting both sides of the equal sign, we get: m*(sin(β+α1)-sin(β+α2))=(L2-L1)*sin(α1-α2) but: m*(2cos((2*β+α1+α2) / 2)sin((α1-α2) / 2)=(L2-L1)*sin(α1-α2)cos((2*β+α1+α2) / 2)=(L2-L1)*sin(α1-α2) / (2*m*sin((α1-α2) / 2)) then: β+(α1+α2) / 2=2kπ±arccos((L2-L1)*sin(α1-α2)) / (2*m*sin((α1-α2) / 2)))Then, the calculation formula of the angle β between the angle zero position of the angle sensor and the direction of the basic track or wing track is: β=2kπ±arccos((L2-L1)*sin(α1-α2) / (2*m*sin((α1-α2) / 2)))-(α1+α2) / 2, where 0°≤β≤90°; The calculation formula for R is obtained according to m*sin(β+α2)=(L1+R)*sin(α1-α2) or m*sin(180°-(β+α1))=(L2+R)*sin(α1-α2).

4. The calibration method of the orthogonal motion detection device according to claim 2, characterized in that: The calculation of the distance from the center hole of the sliding rod joint to the coordinate origin and the angle between the zero angle of the rotation angle sensor and the coordinate axis when the sliding rod is at the extreme position according to the calibration algorithm includes the following steps: Construct a coordinate system with the direction of the basic rail or wing rail as the X-axis, the rotation center of the detection device as the coordinate origin, and the direction perpendicular to the basic rail or wing rail as the Y-axis. The Y coordinates of the two calibration points are equal in the calibrated and solved coordinate system, and the difference in the X coordinates is equal to the distance between the two calibration points; The rotation center of the detection device is set to O. The distance from the rotation center O of the detection device to the center hole of the sliding rod joint is R when the sliding rod is at the retracted limit position. The calibration points are A and B, and the distance is m. When the center hole of the sliding rod joint moves to A and B, the displacements relative to the retracted limit are L1 and L2, respectively. The angle values ​​measured by the angle sensor are α1 and α2, respectively. Then, if the angle zero position of the angle sensor is OP and is located between the X-axis and OB, then ∠POA=α1, ∠POB=α1, and the angle between the angle zero position of the angle sensor and the direction of the basic rail or wing rail is the angle β between OP and the X-axis; Construct a circle with OA as diameter and determine that the intersection of this circle and OB is C; in triangle ABC, ∠BAC = ∠a, ∠ACB = ∠c and ∠ABC = ∠b; Using the law of sines we have: Then, the three interior angles of the triangle are: ∠b＝α2+β Substituting into the sine formula we get: According to the trigonometric function formula sin(90°+α)=cosα, sin(90°-α)=cosα, the formula changes to: Wherein, 0°≤β≤90°; the calculation formula of the angle β between the zero position of the angle sensor and the direction of the basic rail or wing rail is obtained from the above formula; The calculation formula for R is obtained according to m*sin(β+α2)=(L1+R)*sin(α1-α2) or m*sin(180°-(β+α1))=(L2+R)*sin(α1-α2).

5. The calibration method of the orthogonal motion detection device according to claim 3 or 4, characterized in that: If the angle zero position OP of the angle sensor is not between the X-axis and OB, the angle zero position of the angle sensor is rotated to meet the requirements, and physical angle rotation or numerical compensation is performed; wherein, the numerical compensation method is to subtract the angle value that needs to be rotated from the output angle of the angle sensor. The angle sensor is powered off and then powered on again. If the rotated angle zero position cannot be maintained, the angle of the angle zero position must be recorded in the software. In subsequent calculations, the angle β between the angle zero position of the angle sensor and the basic track or wing track direction must be used as a calculation parameter at the same time.

6. The calibration method of the orthogonal motion detection device according to claim 2, characterized in that: The on-site calibration tool is installed and fixed on the basic rail or wing rail during the calibration process; the on-site calibration tool includes a hook head assembly and a calibration plate; the hook head assembly is clamped to the basic rail or wing rail, and the calibration plate is located on the other side of the basic rail or wing rail; the hook head assembly includes a calibration hook head, a hook head bolt and a nut; when in use, the calibration hook head and the hook head parts of the hook head bolt are respectively tightly attached to the two sides and the bottom of the basic rail or wing rail, the bolt part of the hook head bolt passes through the calibration hook head, and the end of the bolt part of the hook head bolt is fixed to the calibration hook head through the nut; the calibration plate is an L-shaped or T-shaped component; one side of the calibration plate is detachably fixed to the calibration hook head, and the other side is provided with calibration points, and the connection direction of the calibration points is parallel to the extension direction of the basic rail or wing rail.

7. The calibration method of the orthogonal motion detection device according to claim 2, characterized in that: The base of the detection device is provided with an anti-rotation structure, which cooperates with the mounting bracket to prevent the detection device from rotating relative to the mounting bracket, including an anti-rotation slot or a positioning pin; the manufacturing plant calibration tooling is provided with an anti-rotation structure matching the detection device.

8. The calibration method of the orthogonal motion detection device according to claim 7, characterized in that: The mounting bracket includes a mounting hook head and a mounting hook head bolt; when in use, the mounting hook head and the hook head parts of the mounting hook head bolt are respectively pressed against the two sides and the rail bottom of the basic rail or the wing rail, the bolt part of the mounting hook head bolt passes through the mounting hook head, and the end of the bolt part of the mounting hook head bolt is fixed to the mounting hook head by a nut; a mounting plate extends outward from the mounting hook head; and a mounting hole for fixing the detection device is provided on the mounting plate.

9. The calibration method of the orthogonal motion detection device according to claim 1, characterized in that: The calibration tooling includes a limit sleeve for limiting the sliding rod to be retracted to an extreme position. During the calibration process and on-site restoration process, when the sliding rod needs to be retracted to an extreme position, the limit sleeve is clamped on the outer periphery of the sliding rod, and the limit sleeve is removed after completion.

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