Detection Method for Limiting Plate in Intelligent Tensioning

Abstract

A detection method for the limit plate in intelligent tensioning is to install a rangefinder on the jack assembly, and set an initial position, a second angle measurement position point, a first angle measurement position point, a first limit plate edge position point, a second limit plate edge position point, and a third limit plate edge position point on the limit plate. By measuring the parameters of the above positions and calculating respectively, the angle of the limit plate, the center and radius of the limit plate are obtained, and the automatic control is carried out by the control center. Its advantage is that by automatically detecting the angle of the limit plate and the three-point coordinates of the edge of the limit plate, the control center can calculate parameters such as the angle between the jack assembly and the limit plate, the center and radius of the limit plate. These parameters are input into the control center for calculation, so as to control the XYZA four-axis positioning system to adjust the position of the jack assembly to the correct position and carry out intelligent tensioning construction.

Description

Technical Field

[0001] The present invention relates to the field of tensioning technology in prestressed construction, and specifically, to a method for detecting a limiting plate in intelligent tensioning. Background Art

[0002] In prestressed construction, it is necessary to thread steel strands between a jack assembly and a beam and then perform tensioning. The construction method is to manually install the jack assembly at the front end of the beam, thread the strand, and then perform tensioning. These constructions require a large amount of manual operations, and continuous disassembly and assembly of equipment, which are time-consuming and laborious, with low efficiency and unable to accurately measure some construction parameters. Although there is an idea of automatic control based on the position of the limiting plate, how to measure parameters such as the inclination angle of the limiting plate, the center and radius of the limiting plate is a technical problem that urgently needs to be solved. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for detecting a limiting plate in intelligent tensioning that can automatically detect the angle between a jack assembly and a limiting plate, the center and radius of the limiting plate in an XYZ A four-axis positioning system.

[0004] The technical solution disclosed by the present invention is:

[0005] A method for detecting a limiting plate in intelligent tensioning, comprising the steps of:

[0006] (1) Step of setting the initial position of the limiting plate and the second position point for angle measurement: Set the initial position and the second position point for angle measurement on the limiting plate. The setting rule for this point is that starting from the initial position and the second position point for angle measurement, the horizontal and vertical movement paths shall not intersect with the holes of the limiting plate;

[0007] (2) Step of setting the position points for limiting plate angle measurement: Set the first position point for angle measurement in the vertical direction starting from the initial position and the second position point for angle measurement;

[0008] (3) Step of detecting the contour edge of the limiting plate: Starting from the initial position and the second position point for angle measurement, set the edge of the limiting plate on the left and right horizontal sides as the first limiting plate edge position point and the second limiting plate edge position point respectively, and set the edge of the limiting plate at the upper end in the vertical direction as the third limiting plate edge position point; or starting from the initial position and the second position point for angle measurement, set the edge of the limiting plate on the left and right horizontal sides as the first limiting plate edge position point and the second limiting plate edge position point respectively, and set the edge of the limiting plate at the lower end in the vertical direction as the third limiting plate edge position point;

[0009] (4)Steps for detecting the angle of the limit plate: Use a rangefinder. The measuring point of the rangefinder measures the distance to the first position point for angle measurement and records the coordinates of this point. Then move the rangefinder up and down. The measuring point of the rangefinder measures the distances to the initial position and the second position point for angle measurement and records the coordinates of this point. By measuring the distance between the above two points, calculate the inclination angle of the limit plate.

[0010] (5)Steps for detecting the center of the limit plate: The rangefinder measures the distances to the first edge position point, the second edge position point, and the third edge position point of the limit plate set in step (3) respectively, and automatically reads the three coordinates of the above three points on the edge contour of the limit plate. Then, through the three measured coordinates, automatically calculate the center coordinates of the limit plate and the radius R of the limit plate. The four-axis positioning system automatically judges whether the calculated radius of the limit plate is consistent with the preset radius of the limit plate. If not, it is sent to the center counter for calculation. After calculation, input it again to perform the operation of automatically reading the three coordinates of the edge contour of the limit plate. Repeat the above steps until the radius of the limit plate is consistent with the preset radius of the limit plate.

[0011] As a preferred solution, in the above step (5), the calculation method for calculating the angle of the cross-section of the jack assembly relative to the cross-section of the limit plate is: Angle A = ATAN (difference in Z-axis two-point coordinates / difference in Y-axis two-point distance measurement).

[0012] As a preferred solution, the rangefinder used in the above step (4) is a laser rangefinder, and the rangefinder is installed on the jack assembly at the output end of the XYZA four-axis positioning system.

[0013] As a preferred solution, the rangefinder used in the above step (4) is a laser rangefinder, and the rangefinder is installed on the piston of the jack assembly at the output end of the XYZA four-axis positioning system. At this time, a servo is installed on the piston, and the output shaft of the servo installs the rangefinder. Driven by the servo, the rangefinder moves outward from the center of the jack to measure the limit plate.

[0014] As a preferred solution, the rangefinder used in the above step (5) is a laser rangefinder. At this time, the method for setting the three coordinates of the edge contour of the limit plate is measured by the laser displacement value jump change method, that is, a sudden step is set at the edge of the end face of the limit plate. The PLC reads the displacement value of the laser displacement sensor in real time through the MODBUS bus communication protocol. When it is monitored that the laser displacement is at the position of the sudden step and the laser displacement value jumps and changes beyond the preset value, the PLC judges that the edge position coordinate setting is successful and records and saves it.

[0015] As a preferred solution, the rangefinder used in step (4) is a touch sensor, which is installed on the jack assembly at the output end of the XYZA four-axis positioning system; during the movement of the jack in the jack assembly along the Z-axis direction, when the touch sensor head contacts the first position point for measuring the angle of the limit plate, the jack stops and records the Z-axis coordinate, retracts the touch sensor head, the jack returns to the position before detection along the Z-axis, the jack moves down by L along the Y-axis, extends the touch sensor head, the jack moves along the Z-axis direction, when the jack moves along the Z-axis direction and the touch sensor head contacts the initial position and the second position point for measuring the angle, the jack stops and records the Z-axis coordinate, and the inclination angle of the limit plate is obtained by calculation.

[0016] As a preferred solution, the rangefinder used in step (4) is a touch sensor. By contacting the touch sensor head with the first position point of the limit plate edge, the second position point of the limit plate edge, and the third position point of the limit plate edge set in step (3) respectively, the three coordinates of the above three points in the limit plate contour edge are automatically read, and then the center coordinates of the limit plate and the radius R of the limit plate are automatically calculated through the three measured coordinates; the four-axis positioning system automatically judges whether the calculated radius of the limit plate is consistent with the preset radius of the limit plate. If not, it is sent to the center counter for calculation, and after calculation, it is input to perform the operation of automatically reading the three coordinates of the limit plate contour edge again. Repeat the above steps until the radius of the limit plate is consistent with the preset radius of the limit plate.

[0017] The beneficial effects of the present invention are: by automatically detecting the angle of the limit plate and the three coordinates of the edge of the limit plate, parameters such as the angle between the jack assembly and the limit plate, the center of the limit plate, and the radius can be calculated by the control center. These parameters are input into the control center for calculation, so as to control the XYZA four-axis positioning system to adjust the position of the jack assembly to the correct position for intelligent tensioning construction. Description of the Drawings

[0018] Figure 1 It is a schematic diagram of the touch sensor of the present invention extending for detection.

[0019] Figure 2 It is a schematic diagram of the retracted state of the touch sensor of the present invention.

[0020] Figure 3 It is a schematic diagram of the present invention contacting the A point of the limit plate edge.

[0021] Figure 4 It is a schematic diagram of the present invention setting detection points on the limit plate.

[0022] Figure 5 It is a structural diagram of the XYZA four-axis positioning control system for realizing movement.

[0023] Figure 6 isFigure 5 Front view.

[0024] Figure 7 is Figure 5 Right view of

[0025] Figure 8 Schematic diagram for measuring angle.

[0026] Figure 9 Schematic diagram of the structure where the laser rangefinder is installed on the piston of the jack assembly.

[0027] Figure 10 is Figure 9 Front view when the laser rangefinder is working.

[0028] Figure 11 is Figure 9 Front view when the laser rangefinder stops working.

[0029] Figure 12 Schematic diagram of the state when the steel strand is stretched to the longest.

[0030] Figure 13 Schematic diagram of the structure of the limit plate 1 of the present invention.

[0031] Figure 14 Schematic diagram of the coordinates set by the limit plate 1.

[0032] Details of the attached drawing components are as follows: 1. Limit plate, 2. XYZA four-axis positioning control system, 3. Rangefinder, 4. Electric cylinder assembly, 5. Jack assembly, 22. Z-axis moving base, 23. X-axis guide rail, 24. X-axis moving base, 25. Z-axis servo motor and reducer, 26. Z-axis rack, 27. Z-axis driving gear, 28. X-axis servo motor and reducer, 29. X-axis driving gear, 210. X-axis rack, 211. Y-axis guide rail, 212. Steel wheel, 213. Chain, 214. Chain guide wheel, 215. Y-axis servo motor and electric cylinder, 216. Z-axis guide rail, 32. Jack, 33. Mounting bracket, 34. Steering gear, 35. Steel strand, 36. Tool anchor assembly, A. Point 1 at the edge position of the limit plate, B. Initial position and point 2 for measuring angle, C. Point 1 for measuring angle, D. Point 2 at the edge position of the limit plate, E. Point 3 at the edge position of the limit plate. Detailed implementation manners

[0033] The present invention will be further described and explained below in conjunction with specific embodiments and the attached drawings of the specification:

[0034] Please refer to Figure 1 , Figure 2 , Figure 3 , Figure 4 , in Embodiment 1 of the present invention, the rangefinder 3 adopted is a touch sensor, and the steps adopted are as follows:

[0035] (1) Installation steps of the touch sensor: Install the touch sensor on the jack assembly 5 at the output end of the XYZA four-axis positioning system 2, with the sensing head of the touch sensor facing the limit plate 1;

[0036] (2) Steps for setting the initial position of the limit plate and the second position point for angle measurement: Set the initial position and the second position point B for angle measurement on the limit plate. The setting rule for this point is that starting from the initial position and the second position point B for angle measurement, the horizontal and vertical movement paths shall not intersect with the holes on the limit plate. In this embodiment, the B point is set at the lower right corner of the limit plate;

[0037] (3) Steps for setting the angle measurement position point of the limit plate: Set the first position point A for angle measurement in the vertical direction starting from the initial position and the second position point for angle measurement;

[0038] (4) Steps for detecting the contour edge of the limit plate: In this embodiment, starting from the initial position and the second position point B for angle measurement, the edges of the limit plate in the horizontal direction on the left and right sides are respectively set as the first limit plate edge position point A and the second limit plate edge position point D, and the edge of the limit plate at the upper end in the vertical direction is set as the third limit plate edge position point E;

[0039] Similarly, starting from the initial position and the second position point for angle measurement, the edges of the limit plate in the horizontal direction on the left and right sides can also be respectively set as the first limit plate edge position point A and the second limit plate edge position point D, and the edge of the limit plate at the lower end in the vertical direction is set as the third limit plate edge position point E;

[0040] (5) Steps for detecting the angle of the limit plate: Extend the touch sensing head, and the jack moves along the Z-axis direction. When the touch sensing head contacts the first position point C for angle measurement of the limit plate, the jack stops and records the Z-axis coordinate. Retract the touch sensing head, and the jack returns to the position before detection along the Z-axis. The jack moves down by L along the Y-axis, extends the touch sensing head, and the jack moves along the Z-axis direction. When the jack moves along the Z-axis direction and the touch sensing head contacts the initial position and the second position point B for angle measurement, the jack stops and records the Z-axis coordinate. Calculate the tilt angle of the limit plate; the calculation method for calculating the angle of the cross-section of the jack assembly relative to the cross-section of the limit plate is: Angle A = ATAN (difference in Z-axis two-point coordinates / difference in Y-axis two-point distance measurement), as Figure 8 shown.

[0041] After obtaining the above angle, the control center makes adjustments. The adjustment steps include:

[0042] 1) The XYZA servo system automatically corrects the angles of the jack assembly and the limit plate through the calculated angle deviation to keep them in a parallel state;

[0043] 2) The XYZA servo system compares the offset distance between the center of the limit plate calculated by trigonometric functions with the center of the jack assembly preset by the system, and automatically corrects the centers of the jack and the limit plate to make them concentric.

[0044] (6) Steps for detecting the center of the limit plate: The control induction head contacts point A at the edge position 1 of the limit plate, point D at the edge position 2 of the limit plate, and point E at the edge position 3 of the limit plate set in step (4) respectively, and automatically reads the three coordinates of the above three points on the edge of the limit plate contour. Then, according to the formula for finding the center and radius of a circle from three points on the circle based on the three measured coordinates, the center coordinates of the limit plate and the radius R of the limit plate are automatically calculated. The four-axis positioning system automatically determines whether the calculated radius of the limit plate is consistent with the preset radius of the limit plate. If not, it is sent to the center counter for calculation, and after calculation, it is input to perform the operation of automatically reading the three coordinates of the edge of the limit plate contour again. Repeat the above steps until the radius of the limit plate is consistent with the preset radius of the limit plate.

[0045] See Figure 5 、 6 As shown in FIGS. 7, in the XYZA four-axis positioning control system of the present invention, the Z-axis guide rail 216 is connected to the Z-axis moving base 22, and the Z-axis servo motor and reducer 25, the Z-axis rack 26, and the Z-axis drive gear 27 constitute the Z-axis drive unit; the X-axis guide rail 23 is connected to the X-axis moving base 24, and the X-axis servo motor and reducer 28, the X-axis drive gear 29, and the X-axis rack 210 constitute the X-axis drive unit; the Y-axis guide rail 211, the steel wheel 212, the chain 213, the chain guide wheel 214, and the Y-axis servo motor and electric cylinder 215 constitute the Y-axis drive unit, and the electric cylinder assembly 4 pushes the jack assembly to rotate to form the A-axis rotation mechanism.

[0046] As Figure 9 、 10 As shown in FIGS. 11, 12, 13, and 14, in Embodiment 2 of the present invention, the distance measuring instrument 3 is a laser distance measuring instrument, and the difference from Embodiment 1 is that the method for setting the three coordinates of the edge of the limit plate contour is measured by the laser displacement value jump change method, that is, a sudden step is set at the edge of the end face of the limit plate. The PLC reads the displacement value of the laser displacement sensor in real time through the MODBUS bus communication protocol. When it is monitored that the laser displacement is at the position of the sudden step and the laser displacement value jumps and changes by more than the preset value, the PLC determines that the edge position coordinates are set successfully and records and saves them.

[0047] At this time, a sudden step is set at the edge of the end face of the limit plate. When the laser distance measuring instrument measures the position of this step, the edge position is judged by the jump change of the laser displacement value. One structure is as Figure 13 、 14As shown, on the basis of the traditional limit plate, a raised step is added at the back of the limit plate, mainly to facilitate the laser rangefinder to effectively identify the jump of the distance, so as to identify the edge of the outer diameter, find the edge coordinate positions at three different locations, and achieve the purpose of automatically detecting the center of the limit plate. Its working principle is as follows: on the basis of the traditional limit plate, a raised step is added. Generally, 5-10 mm needs to be added to the outer diameter on one side, and the depth is ≥ 20 mm. The laser rangefinder emits laser light and hits the initial point of the limit plate, and records the measured distance value. The laser moves horizontally. When the laser sweeps across the edge position coordinate 1, the increment of the laser ranging is greater than the value set by the program, and the laser rangefinder stops moving forward and records the coordinate value. For example: the judgment value set by the program is ≥ 15 mm, the initial point ranging is 300 mm, when sweeping across the edge position coordinate 1, the ranging is 320 mm, and the increment value is 20 mm, which meets the requirements of the judgment value, and the laser rangefinder stops moving forward. Similarly, the coordinates of the edge position coordinates 2 and 3 are found in turn. With the three coordinate values, the center coordinate of the limit plate can be calculated; a light color, such as white or milky white, is sprayed on the front surface of the limit plate to facilitate the laser to identify the limit plate and improve the ranging accuracy.

[0048] There are two installation positions for the laser rangefinder:

[0049] First, as Figure 7 shown, the rangefinder 3 is installed on the top of the jack assembly.

[0050] Second, as Figure 9 、 10 、11、12 shown, the mounting bracket 33 is fixed on the piston of the jack, the servo motor 34 is fixed on the mounting bracket 33, the laser rangefinder is fixedly connected to the output shaft of the servo motor 34, the servo motor 34 can be positioned at any angle within the range of 0-180 degrees, and the positioning accuracy is above 0.3, for angle detection and center detection; after the laser rangefinder finishes working, the servo motor angle is adjusted to turn the laser rangefinder to the inner hole edge of the jack piston; when the steel strand 35 is stretched during tensioning, when the steel strand 35 is stretched to the longest, the laser rangefinder will not interfere with the steel strand, and the laser rangefinder can pass through the hole of the tool anchor assembly and shoot at the limit plate to perform angle detection and center detection of the amount.

[0051] The advantages of placing the laser rangefinder inside the piston: After detecting the angle and adjusting the angle, it needs to move back to the laser initial position point, and after detecting the center position, the jack needs to be moved to the center position. For these two moving actions, the jack needs to move up along the Y-axis. However, when the laser rangefinder is installed inside, the moving distance is smaller than that when installed outside, which can shorten the moving time and improve the efficiency; it saves the external space; when installed outside, it is easily collided, and the laser rangefinder also needs to add a protective device, while when placed inside, there is no need to worry about being collided.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A method for detecting a limit plate in intelligent tensioning, comprising the steps: (1) Steps for setting the initial position of the limit plate and the second position point for measuring the angle: Set the initial position and the second position point for measuring the angle on the limit plate. The setting rule for this point is that starting from the initial position and the second position point for measuring the angle, the horizontal and vertical movement paths shall not intersect the holes of the limit plate; (2) Steps for setting the position point for measuring the angle of the limit plate: Set the first position point for measuring the angle in the vertical direction starting from the initial position and the second position point for measuring the angle; (3) Steps for detecting the contour edge of the limit plate: Starting from the initial position and the second position point for measuring the angle, set the edges of the limit plate in the horizontal direction on the left and right sides as the first limit plate edge position point and the second limit plate edge position point respectively, and set the edge of the limit plate at the upper end in the vertical direction as the third limit plate edge position point; or starting from the initial position and the second position point for measuring the angle, set the edges of the limit plate in the horizontal direction on the left and right sides as the first limit plate edge position point and the second limit plate edge position point respectively, and set the edge of the limit plate at the lower end in the vertical direction as the third limit plate edge position point; (4) Steps for detecting the angle of the limit plate: Use a rangefinder. The measuring point of the rangefinder measures the distance to the first position point for measuring the angle and records the coordinates of this point; then move the rangefinder up and down, and the measuring point of the rangefinder measures the distance to the initial position and the second position point for measuring the angle and records the coordinates of this point; by measuring the distance between the above two points, calculate the inclination angle of the limit plate; (5) Steps for detecting the center of the limit plate: The rangefinder measures the distances to the first limit plate edge position point, the second limit plate edge position point, and the third limit plate edge position point set in step (3) respectively, automatically reads the three coordinates of the above three points on the contour edge of the limit plate, and then automatically calculates the center coordinates of the limit plate and the radius R of the limit plate through the three measured coordinates; the four-axis positioning system automatically judges whether the calculated radius of the limit plate is consistent with the preset radius of the limit plate. If not, it is sent to the center counter for calculation, and after calculation, it is input for the operation of automatically reading the three coordinates of the contour edge of the limit plate again. Repeat the above steps until the radius of the limit plate is consistent with the preset radius of the limit plate.

2. The method for detecting a limit plate in intelligent tensioning according to claim 1, characterized in that: In the step (4), the calculation method for calculating the angle of the cross-section of the jack assembly relative to the cross-section of the limit plate is: Angle A = ATAN (difference in Z-axis two-point coordinates / difference in Y-axis two-point distance measurement); 3. The method for detecting a limit plate in intelligent tensioning according to claim 1, characterized in that: The rangefinder used in the step (4) is a laser rangefinder, and the rangefinder is installed on the jack assembly at the output end of the XYZA four-axis positioning system.

4. The method for detecting a limit plate in intelligent tensioning according to claim 1, characterized in that: The rangefinder used in step (4) is a laser rangefinder, which is installed on the piston of the jack assembly at the output end of the XYZA four-axis positioning system. At this time, a servo motor is installed on the piston, and the output shaft of the servo motor is installed with the rangefinder. Driven by the servo motor, the rangefinder moves outward from the center of the jack to measure the limit plate.

5. The method for detecting the limit plate in intelligent tensioning according to claim 4, wherein: The rangefinder used in step (5) is a laser rangefinder. At this time, the method for setting the three coordinates of the contour edge of the limit plate uses the laser displacement value jump change method for measurement, that is, a sudden step is set at the edge of the end face of the limit plate. The PLC reads the displacement value of the laser displacement sensor in real time through the MODBUS bus communication protocol. When it is monitored that the laser displacement is at the position of the sudden step and the laser displacement value jumps and changes by more than the preset value, the PLC determines that the edge position coordinates are set successfully and records and saves them.

6. The method for detecting the limit plate in intelligent tensioning according to claim 1, wherein: The rangefinder used in step (4) is a touch sensor, which is installed on the jack assembly at the output end of the XYZA four-axis positioning system. During the movement of the jack in the Z-axis direction in the jack assembly, when the touch sensing head contacts the first position point for measuring the angle of the limit plate, the jack stops and records the Z-axis coordinate. The touch sensing head is retracted, the jack returns to the position before detection along the Z-axis, the jack moves down by L along the Y-axis, the touch sensing head is extended, and the jack moves in the Z-axis direction. When the jack moves in the Z-axis direction and the touch sensing head contacts the initial position and the second position point for measuring the angle, the jack stops and records the Z-axis coordinate, and the inclination angle of the limit plate is calculated.

7. The method for detecting the limit plate in intelligent tensioning according to claim 1, wherein: The rangefinder used in step (4) is a touch sensor. The touch sensing head contacts the first limit plate edge position point, the second limit plate edge position point, and the third limit plate edge position point set in step (3) respectively, and automatically reads the three coordinates of the above three points on the contour edge of the limit plate. Then, the center coordinate of the limit plate and the radius R of the limit plate are automatically calculated through the three coordinates measured. The four-axis positioning system automatically judges whether the calculated radius of the limit plate is consistent with the preset radius of the limit plate. If not, it is sent to the center counter for calculation, and after calculation, it is input to perform the operation of automatically reading the three coordinates of the contour edge of the limit plate again. Repeat the above steps until the radius of the limit plate is consistent with the preset radius of the limit plate.

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