Method for automatically measuring rotation angle of bridge

Abstract

The invention discloses a bridge rotation angle automatic measurement method, which comprises the following steps: arranging a coding ruler on a bridge, and driving the coding ruler to rotate synchronously when the bridge rotates horizontally; a photoelectric reading instrument is fixedly arranged, and when the coded ruler rotates, relative displacement is generated between the coded ruler and the photoelectric reading instrument; and the photoelectric reading instrument identifies the Gray code on the coded ruler, and determines the rotation angle of the bridge according to the Gray code. The measuring efficiency can be remarkably improved, automatic measurement is achieved, and the precision of the measuring result is high.

Description

Technical Field

[0001] The invention relates to the field of horizontal rotation of bridges, and in particular to an automatic measurement method for the rotation angle of a bridge. Background Art

[0002] Horizontal rotation is a common construction process in bridge construction across railways. During the rotation process, the rotation angle and angular velocity must be mastered in real time to determine the rotation status of the rotating T-structure. The traditional method of measuring the rotation angle is to stick an angle tape ruler on the turntable, indicate the angle position with a pointer, and read and record it manually, but this method cannot achieve automated measurement and recording.

[0003] In order to improve the above measurement technology, currently, there is also a measurement technology that uses a wire displacement meter to measure the displacement of the turntable line and then converts it into a rotation angle, and there is also a measurement technology that uses a satellite navigation system receiver to monitor the displacement of the rotating T-beam end and then converts it into a rotation angle. However, these two types of monitoring and measurement technologies have the problem of low measurement efficiency and low accuracy.

[0004] Therefore, in order to solve the above problems, a method for automated measurement of bridge rotation angle is needed, which can significantly improve the measurement efficiency, realize automated measurement, and achieve high measurement accuracy. Summary of the invention

[0005] In view of this, the purpose of the present invention is to overcome the defects in the prior art and provide an automated measurement method for the bridge rotation angle, which can significantly improve the measurement efficiency, realize automated measurement, and achieve high-precision measurement results.

[0006] The automatic measurement method of bridge rotation angle of the present invention comprises:

[0007] The code ruler is set on the bridge, and the code ruler is driven to rotate synchronously when the bridge rotates horizontally;

[0008] A photoelectric reader is fixedly arranged, and when the code ruler rotates, the code ruler and the photoelectric reader produce relative displacement;

[0009] The photoelectric reader recognizes the Gray code on the coding ruler and determines the rotation angle of the bridge according to the Gray code.

[0010] Further, the length L of the coding ruler is:

[0011] L=πR*θ m / 180+0.2;

[0012] Where R is the radius of the turntable on the rotating bridge; θ m is the maximum rotation angle.

[0013] Furthermore, the coding ruler has a reading area and a barcode area in the width direction;

[0014] The reading area is marked with colored markings for every 0.1° angle. The integer angle grooves are lengthened and digital markings are printed at the same time.

[0015] The spacing of each angle groove is:

[0016] The number of grooves is: The angle mark starts from 0° and the maximum value θ max is the maximum rotation angle θ m Round up.

[0017] Furthermore, a code is made on the coding ruler corresponding to each scale line by punching, and the code is a 10-bit Gray code, where a round hole or a square hole represents the number 0, and a non-punched hole represents the number 1.

[0018] Furthermore, the bridge rotation angle θ is determined according to the following formula:

[0019]

[0020] Among them, G n G n-1 ...G1G0 is Gray code; n is the highest digit of Gray code.

[0021] Furthermore, the method further includes: calculating the rotation angular velocity V according to the time difference between two adjacent scales:

[0022]

[0023] Among them, t1 is the time of the previous scale, and t2 is the time of the next scale.

[0024] Furthermore, the method further includes: correcting the rotation angle at a certain moment according to the following formula:

[0025] θ t+Δt =θ t +Δt×V;

[0026] Among them, θ t+Δt is the rotation angle at time t+Δt; θ t is the rotation angle at time t; Δt is the time interval, and V is the angular velocity of rotation.

[0027] The beneficial effects of the present invention are as follows: the present invention discloses an automated measurement method for the rotation angle of a bridge, which realizes the effect of automated measurement of the rotation angle, significantly improves the measurement efficiency, and also supports manual reading, and has the advantages of automated measurement, self-correction according to coding rules, absolute value measurement, high precision, etc., by designing a high-precision coding ruler, based on the binary Gray code coding principle, and using a photoelectric reader to identify the Gray code on the coding ruler, and directly using the Gray code to obtain the rotation angle of the bridge. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0029] Figure 1 It is a schematic flow chart of the automated measurement method of the present invention;

[0030] Figure 2 It is a schematic diagram of the structure of the coding ruler of the present invention;

[0031] Figure 3 It is a schematic diagram of measuring using a photoelectric reader and a coding ruler according to the present invention. DETAILED DESCRIPTION

[0032] The present invention is further described below in conjunction with the accompanying drawings, as shown in the drawings:

[0033] This embodiment discloses a method for automatically measuring the angle of a bridge rotation, comprising the following steps:

[0034] The code ruler is set on the bridge, and the code ruler is driven to rotate synchronously when the bridge rotates horizontally;

[0035] A photoelectric reader is fixedly arranged, and when the code ruler rotates, the code ruler and the photoelectric reader produce relative displacement;

[0036] The photoelectric reader recognizes the Gray code on the coding ruler and determines the rotation angle of the bridge according to the Gray code.

[0037] When measuring, the horizontal rotation of the bridge will drive the encoder ruler to rotate synchronously, so the encoder ruler and the fixed photoelectric reader will have a relative displacement. The photoelectric reader recognizes the Gray code on the encoder ruler and converts the Gray code into a real rotation angle through reverse conversion.

[0038] In this embodiment, the code ruler can be made of 0.2 mm stainless steel sheet. The length of the stainless steel sheet is determined by the maximum rotation angle and the radius of the turntable on the rotating bridge. The length L of the code ruler is:

[0039] L=πR*θ m / 180+0.2;

[0040] Where R is the radius of the turntable on the rotating bridge; θ m The value 0.2 is in meters, and 0.2 is the blank area set outside the rotation angle when making the code ruler, which can improve reading accuracy and reduce the risk of misreading, while ensuring that the code ruler has enough space to adapt to different measurement requirements and improve the user's operating experience.

[0041] like Figure 2As shown, the coding ruler has a reading area and a barcode area in the width direction; wherein, there is a strong adhesive strip on the back of the reading area, and during installation, the coding ruler is fixed to the lower edge of the side of the turntable on the rotating bridge by the adhesive strip, and the barcode area is suspended below the turntable to facilitate reading by the photoelectric reader.

[0042] The reading area is marked with colored markings for every 0.1° angle. The integer angle grooves are lengthened and digital markings are printed at the same time.

[0043] The spacing of each angle groove is:

[0044] The number of grooves is: The angle mark starts from 0° and the maximum value θ max is the maximum rotation angle θ m Round up.

[0045] The coding is made on the coding ruler by punching holes corresponding to each scale line. The coding is a 10-bit Gray code, where round or square holes represent the number 0 and non-punched holes represent the number 1. Among them, the 10-bit Gray code can support a maximum coding requirement of 102.3 degrees, which can meet the rotation angle measurement requirements of general rotating bridges.

[0046] In this embodiment, the conversion formula between Gray code and binary code is as follows:

[0047] G n =E n

[0048]

[0049] So we have:

[0050]

[0051] Where: G n G n-1 ...G1G0 is Gray code, is binary code, Represents the XOR operation, the same is 0, and different is 1.

[0052] The binary code is converted into decimal code, the formula is as follows:

[0053]

[0054] Where: S represents the decimal code.

[0055] The calculation method of the decimal code is: the integer corresponding to the angle represented by the scale line × 10 is first converted into a binary code and then into a Gray code.

[0056] The angle calculation formula for the gray code corresponding to the scale line is:

[0057]

[0058] Then, the bridge rotation angle θ can be determined according to the following formula:

[0059]

[0060] Among them, G n G n-1 ...G1G0 is Gray code; n is the highest digit of Gray code.

[0061] In this embodiment, the photoelectric reader can use an existing photoelectric reading device; the photoelectric reader includes a vertically arranged laser emitter array and a laser receiver array, and the arrangement size of the emitter and the receiver corresponds to the size of a single barcode on the coding ruler. Among them, a laser emitter is installed at the center of the outer top surface of the photoelectric reader, which can emit a laser beam vertically upward to indicate the reading scale position, play a role in assisting manual reading, and should be aligned with the 0 position on the scale line during initial installation.

[0062] The photoelectric reader can determine the opening and closing state (i.e. light or dark) of the code position through the laser signal emitted by the transmitter and received by the receiver, and then determine the value of the Gray barcode. Figure 3 As shown in the figure, the photoelectric reader is fixedly installed on the bridge pedestal and remains fixed during the rotation process. When the bridge rotates, the turntable drives the encoder ruler and the photoelectric reader to move relative to each other, and the position of the encoder ruler relative to the photoelectric reader changes, that is, a relative displacement occurs. This displacement reflects the angle of rotation of the bridge, thereby indicating and reading the rotation angle.

[0063] In this embodiment, the photoelectric reader can calculate the rotational angular velocity V according to the time interval between the two scales. If the time of passing the previous scale is t1 and the time of passing the next scale is t2, the specific calculation method is:

[0064]

[0065] In addition, since the rotation angular velocity is relatively slow, it can be considered that the angle change is linear in a short time. In order to improve the display accuracy to 0.01°, the predictive interpolation method can be used to predict the angle at the future moment. Then the angle at time t+Δt is the rotation angle at time t+Δt×V, and this value can be rounded to an accuracy of 0.01°. The rotation angle at a certain moment is corrected according to the following formula:

[0066] θ t+Δt =θ t +Δt×V;

[0067] Among them, θ t+Δtis the rotation angle at time t+Δt; θ t is the rotation angle at time t; Δt is the time interval, and V is the angular velocity of rotation.

[0068] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A method for automatically measuring the rotation angle of a bridge, characterized in that: include: The code ruler is set on the bridge, and the code ruler is driven to rotate synchronously when the bridge rotates horizontally; A photoelectric reader is fixedly arranged, and when the code ruler rotates, the code ruler and the photoelectric reader produce relative displacement; The photoelectric reader recognizes the Gray code on the coding ruler and determines the rotation angle of the bridge according to the Gray code.

2. The automatic measurement method for bridge rotation angle according to claim 1 is characterized in that: The length L of the coding ruler is: L=πR*θ m / 180+0.2; Where R is the radius of the rotating bridge turntable; θ m is the maximum rotation angle.

3. The automatic measurement method for bridge rotation angle according to claim 2 is characterized in that: The coding ruler has a reading area and a barcode area in the width direction; The reading area is marked with colored markings for every 0.1° angle. The integer angle grooves are lengthened and digital markings are printed at the same time. The spacing of each angle groove is: The number of grooves is: The angle mark starts from 0° and the maximum value θ max is the maximum rotation angle θ m Round up.

4. The automatic measurement method for bridge rotation angle according to claim 3 is characterized in that: The code is made on the coding ruler by punching holes corresponding to each scale line. The code is a 10-bit Gray code. Round or square holes represent the number 0, and non-punched holes represent the number 1.

5. The automatic measurement method for bridge rotation angle according to claim 1 is characterized in that: The bridge rotation angle θ is determined according to the following formula: Among them, G n G n-1 …G1G0 is Gray code; n is the highest digit of Gray code.

6. The automatic measurement method for bridge rotation angle according to claim 1 is characterized in that: Also includes: Calculate the angular velocity V using the time difference between two adjacent scales: Among them, t1 is the time of the previous scale, and t2 is the time of the next scale.

7. The automatic measurement method for bridge rotation angle according to claim 6 is characterized in that: Also includes: The rotation angle at a certain moment is corrected according to the following formula: i t+Δt =θ t +Δt×V; Among them, θ t+Δt is the rotation angle at time t+Δt; θ t is the rotation angle at time t; Δt is the time interval, and V is the angular velocity of rotation.

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