Laser telemeter and intelligent response speed adjusting method thereof

Abstract

The application provides a laser remote sensor and an intelligent response speed adjusting method thereof, and comprises the following steps: measuring the detection distance between the laser remote sensor and the pipeline to be inspected; measuring the angular velocity of the laser remote sensor during the inspection process; calculating the moving speed of the laser spot of the laser remote sensor according to the detection distance and the angular velocity; and adjusting the data refresh speed of the laser remote sensor by using the piecewise method according to the moving speed of the laser spot of the laser remote sensor. The application also provides a laser remote sensor for realizing the above process, wherein a laser ranging module, a front-end accelerometer and a rear-end accelerometer are arranged on the laser remote sensor, and each component is connected with a main control module. The application can realize the intelligent adjustment of the response speed of the laser remote sensor, avoid the deterioration of the spatial resolution of the leakage detection caused by the change of the inspection spot speed during the inspection process, help to ensure the spatial resolution of the leakage detection of the laser remote sensor, and improve the data reliability of the laser remote sensor.

Description

Technical Field

[0001] This invention relates to the field of laser absorption spectroscopy (TDLAS) technology, specifically to a laser telemetry instrument and its intelligent response speed adjustment method. Background Technology

[0002] Laser spectral telemetry technology has advantages such as high sensitivity, strong anti-interference ability, and small size, and is widely used in the field of gas leak detection. This technology expands and collimates a laser beam before shining it onto the inspection location, and collects the diffuse reflected light at the inspection location. After photoelectric conversion and signal processing of the collected diffuse reflected light, the concentration information of the target gas at the inspection location can be obtained, thereby determining the location of the gas leak.

[0003] In telemetry applications, the data refresh rate of laser telemetry instruments is usually kept constant, and the laser telemetry area is distributed in a fan shape centered on the telemetry instrument, with a telemetry distance of up to hundreds of meters. Because the distribution of inspected pipelines at varying distances is irregular, when the telemetry angular velocity is constant, the farther the pipeline is from the telemetry instrument, the longer the pipeline length scanned by the laser spot in the same amount of time. This leads to a decrease in the spatial resolution of the laser telemetry instrument for leak detection, posing a risk of lost or invalid inspection data.

[0004] Based on this, the present invention provides a laser telemetry instrument and its intelligent response speed adjustment method to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a laser telemetry instrument and its intelligent adjustment method for response speed. This method enables intelligent adjustment of the response speed of the laser telemetry instrument, avoids the problem of deterioration of the spatial resolution of leakage detection caused by changes in the speed of the inspection spot during the inspection process, helps to ensure the spatial resolution of leakage detection by the laser telemetry instrument, and improves the data reliability of the laser telemetry instrument.

[0006] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:

[0007] (I) This invention provides an intelligent adjustment method for the response speed of a laser telemetry instrument, comprising the following steps: measuring the detection distance between the laser telemetry instrument and the pipeline under inspection; measuring the angular velocity of the laser telemetry instrument during the inspection process; calculating the moving speed of the laser spot of the laser telemetry instrument based on the detection distance and angular velocity; and adjusting the data refresh rate of the laser telemetry instrument based on the moving speed of the laser spot of the laser telemetry instrument.

[0008] Furthermore, the laser telemetry instrument integrates a laser ranging module, and the detection distance between the laser telemetry instrument and the inspected pipeline is determined by the laser ranging module.

[0009] Furthermore, accelerometers are installed at the front and rear ends of the laser telemetry instrument, and the angular velocity of the laser telemetry instrument during the inspection process is calculated from the acceleration values ​​measured by the accelerometers.

[0010] Furthermore, the instantaneous angular velocity ω of the laser telemetry instrument at time T is:

[0011]

[0012] Where t is the time for a single data reading by the laser telemetry instrument; D is the distance between the two accelerometers; Ax n Ay n and Az n These are the acceleration values ​​of the front-end accelerometer in each direction in three-dimensional space at the nth time; Bx n By n and Bz n These are the acceleration values ​​of the back-end accelerometer in each direction in three-dimensional space at the nth time.

[0013] Furthermore, the average moving speed ν of the laser spot of the laser telemetry instrument during a time period t' is:

[0014]

[0015] Among them, L n is the distance measured by the laser ranging module in the nth time; a is the number of measurements within time t', a = t' / t.

[0016] Furthermore, the data refresh rate adjustment method for the laser telemetry instrument is as follows: when the spot movement speed ν is less than 1 m / s, the data refresh rate of the laser telemetry instrument is... Δx is the preset spatial resolution; when the spot movement speed ν is higher than 1m / s and lower than 25m / s, the laser telemetry data refresh rate is... When the laser spot moving speed ν is higher than 25m / s, the laser telemetry data refresh is paused and an alarm message is issued indicating that the laser telemetry inspection speed is too fast.

[0017] Furthermore, when the spot movement speed ν is higher than 1m / s and lower than 25m / s, the control data refresh rate shall not exceed 100Hz.

[0018] (II) The present invention also provides a laser telemetry instrument capable of intelligently adjusting response speed. The laser telemetry instrument is equipped with a laser ranging module, a front-end accelerometer, and a rear-end accelerometer. The laser ranging module is installed on the laser telemetry instrument and is used to determine the detection distance between the laser telemetry instrument and the pipeline being inspected. The front-end accelerometer and the rear-end accelerometer are respectively installed at the front and rear ends of the laser telemetry instrument and are used to detect the acceleration of the front and rear ends of the laser telemetry instrument during the inspection process. The laser telemetry instrument, the laser ranging module, the front-end accelerometer, and the rear-end accelerometer are respectively connected to the main control module. The main control module is used to receive the distance data measured by the laser ranging module and the acceleration data measured by the front and rear accelerometers, calculate the rotational angular velocity of the laser telemetry instrument and the moving speed of the laser spot of the laser telemetry instrument, and adjust the data refresh rate of the laser telemetry instrument.

[0019] Furthermore, the laser ranging module is located at the left or right front end of the laser telemetry instrument; the ranging beam of the laser ranging module is parallel to the output beam of the laser telemetry instrument.

[0020] Furthermore, both the front-end accelerometer and the rear-end accelerometer are located on the central axis of the laser telemetry instrument.

[0021] Beneficial effects

[0022] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0023] This invention provides a laser telemetry instrument and its intelligent response speed adjustment method. The laser telemetry instrument is equipped with a laser ranging module, a front-end accelerometer, and a rear-end accelerometer. The laser ranging module measures the instantaneous distance data of the laser rangefinder, and the two accelerometers read the instantaneous acceleration values ​​of the front and rear accelerometers, calculating the instantaneous movement speed of the laser telemetry spot. Based on the movement speed of the laser spot, a segmented feedback method is used to adjust the data refresh rate of the laser telemetry instrument. This invention enables intelligent adjustment of the laser telemetry instrument's response speed, avoiding the problem of deteriorated spatial resolution in leak detection caused by changes in the speed of the inspection spot during inspection. This helps ensure the spatial resolution of leak detection by the laser telemetry instrument and improves the data reliability of the laser telemetry instrument. Attached Figure Description

[0024] Figure 1 This is a block diagram of the laser telemetry system of the present invention;

[0025] Figure 2 This is a flowchart of the self-adjustment method for the response rate of the laser telemetry instrument of the present invention;

[0026] The labels in the attached diagram are:

[0027] 1. Laser telemetry instrument; 2. Laser ranging module; 3. Front-end accelerometer; 4. Rear-end accelerometer. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] This invention provides a laser telemetry instrument, such as... Figure 1 As shown, it includes a laser telemetry instrument 1, a laser ranging module 2, a front-end accelerometer 3, and a rear-end accelerometer 4.

[0030] Laser ranging module 2 is installed at the front left of laser telemetry instrument 1. The ranging beam of laser ranging module 2 is parallel to the output beam of laser telemetry instrument 1, and is used to determine the detection distance between laser telemetry instrument 1 and the inspected pipeline. The measured distance data is transmitted to the main control module of laser telemetry instrument at a frequency of 1kHz. Front accelerometer 3 and rear accelerometer 4 are installed at the front and rear ends of laser telemetry instrument 1, respectively. Both front accelerometer 3 and rear accelerometer 4 are located on the central axis of laser telemetry instrument 1, and the distance between them is D, which can be approximated as the length of laser telemetry instrument 1. The measured acceleration data is also transmitted to the main control module of laser telemetry instrument at a frequency of 1kHz.

[0031] During the inspection, the distance to the inspected pipeline can be measured using the laser ranging module 2, and the angular velocity of the laser telemetry instrument 1 can be measured using the front-end accelerometer 3 and rear-end accelerometer 4 installed at the front and rear ends. Combining the measured distance and angular velocity, the moving speed of the laser spot can be calculated. Based on this moving speed, the data refresh rate of the laser telemetry instrument is adjusted in real time using a segmented method, ensuring the spatial resolution of the laser telemetry instrument for leak detection.

[0032] The intelligent adjustment method for the response speed of the aforementioned laser telemetry instrument is as follows: Figure 2 As shown, the specific steps include:

[0033] Step 1: Measure the detection distance between the laser telemetry instrument and the pipeline being inspected.

[0034] Read the distance data from the nth measurement by laser ranging module 2 and record it as L. n The data reading frequency is 1kHz.

[0035] Step 2: Measure the angular velocity of the laser telemetry instrument during the inspection process:

[0036] The values ​​of the front-end accelerometer 3 and the rear-end accelerometer 4 are read. The data reading frequency is 1kHz, and the corresponding single data reading time t is 0.001s.

[0037] Among them, the acceleration value of the front-end accelerometer 3 in each direction of the three-dimensional space at the nth time is recorded as Ax. n Ay n and Az n The acceleration values ​​of the back-end accelerometer 4 in each direction in three-dimensional space for the nth time are recorded as Bx. n By n and Bz n When the laser telemetry instrument 1 is powered on, its initial velocity is usually zero. Therefore, the instantaneous velocities of the laser telemetry instrument's front end in various directions in three-dimensional space at time T can be calculated as follows: and The instantaneous velocities of the laser telemetry instrument's back end in various directions in three-dimensional space are respectively and The instantaneous displacements of the laser telemetry instrument front end in various directions in three-dimensional space at time T are respectively and The instantaneous displacements of the laser telemetry instrument's back end in various directions in three-dimensional space are respectively and The instantaneous angular velocity ω of the laser telemetry instrument can be further calculated as follows:

[0038]

[0039] Where D is the distance between the two accelerometers.

[0040] Step 3: Calculate the moving speed of the laser spot of the laser telemetry instrument based on the detection distance and angular velocity:

[0041] Combined with the distance data L from laser ranging module 2 n The average moving speed ν of the laser telemetry spot within 0.01s can be calculated as follows:

[0042]

[0043] Step 4: Adjust the data refresh rate of the laser telemetry instrument according to the moving speed of the laser spot:

[0044] Based on the moving speed of the laser telemetry spot, a segmented feedback method is used to adjust the data refresh rate of laser telemetry instrument 1. The data refresh rate is achieved by adjusting the number of data accumulations for a single spectrum. Setting the single-spectrum scanning frequency of laser telemetry instrument 1 to f (in Hz), and using parallel computing, the fastest data refresh rate of the laser telemetry instrument can be obtained as fHz. To achieve high spatial resolution under high-speed inspection, the spectral scanning frequency typically needs to exceed 10kHz. The detailed segmented adjustment method is as follows:

[0045] When the spot movement speed ν is less than 1 m / s, and the spectral averaging frequency is set to a constant f × Δx times, the corresponding data refresh rate of the laser telemetry instrument is: Where Δx is the preset spatial resolution in meters. If Δx is 0.25m, the corresponding data refresh rate is 4Hz. Within this speed range, the inspection spatial resolution of the laser telemetry instrument is better than 0.25m, which can meet the location judgment requirements of most leakage detection application scenarios.

[0046] When the spot movement speed ν is higher than 1 m / s and lower than 25 m / s, this inspection speed range can meet the inspection speed requirements of both vehicle-mounted and airborne systems. Therefore, the spectral averaging frequency is set to... At this time, the data refresh rate of the laser telemetry instrument is... The average number of spectral frequencies and the data refresh rate are rounded to the nearest integer, and the data refresh rate must be controlled to not exceed 100Hz. Under these conditions, the data refresh rate of the laser telemetry instrument ensures that the inspection spatial resolution remains constant at Δx.

[0047] When the spot movement speed ν is higher than 25m / s, the average number of spectral scans is further reduced due to the limitation of the laser telemetry spectral scanning frequency, the signal-to-noise ratio of spectral measurement is further reduced, the telemetry spatial resolution deteriorates, and the effectiveness of the inspection data is greatly reduced. At this time, the laser telemetry data refresh is paused, and an alarm message indicating that the laser telemetry inspection speed is too fast is displayed.

[0048] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for intelligent adjustment of the response speed of a laser telemetry instrument, characterized in that, Includes the following steps: Determine the detection distance between the laser telemetry instrument and the pipeline under inspection; Measure the angular velocity of the laser telemetry instrument during the inspection process; The moving speed of the laser spot of the laser telemetry instrument is calculated based on the detection distance and angular velocity; Adjust the data refresh rate of the laser telemetry instrument according to the moving speed of the laser spot; The laser telemetry instrument is equipped with accelerometers at its front and rear ends, and the angular velocity of the laser telemetry instrument during the inspection process is calculated from the acceleration values ​​measured by the accelerometers. The instantaneous angular velocity ω of the laser telemetry instrument at time T is: Where t is the time for a single data reading by the laser telemetry instrument; D is the distance between the two accelerometers. , and These are the acceleration values ​​of the front-end accelerometer in each direction in three-dimensional space at the nth time; , and These are the acceleration values ​​of the back-end accelerometer in each direction in three-dimensional space at the nth time; The average moving speed of the laser spot of the laser telemetry instrument within a time period t' for: in, This is the distance measured by the laser ranging module in the nth measurement; a = t' / t; The data refresh rate adjustment method for the laser telemetry instrument is as follows: when the spot movement speed... When the speed is below 1 m / s, the data refresh rate of the laser telemetry instrument is Hz, The preset spatial resolution; when the spot movement speed ν is higher than 1 m / s and lower than 25 m / s, the laser telemetry data refresh rate is... Hz; When the spot movement speed ν is higher than 25 m / s, the laser telemetry data refresh is paused and an alarm message is issued indicating that the laser telemetry inspection speed is too fast.

2. The intelligent adjustment method for the response speed of a laser telemetry instrument according to claim 1, characterized in that, The laser telemetry instrument integrates a laser ranging module, and the detection distance between the laser telemetry instrument and the pipeline under inspection is determined by the laser ranging module.

3. The intelligent adjustment method for the response speed of a laser telemetry instrument according to claim 1, characterized in that, When the spot movement speed ν is higher than 1 m / s and lower than 25 m / s, the control data refresh rate shall not exceed 100 Hz.

4. A laser telemetry instrument for implementing the intelligent response speed adjustment method according to any one of claims 1 to 3, characterized in that: The laser telemetry instrument is equipped with a laser ranging module, a front-end accelerometer, and a rear-end accelerometer. The laser ranging module is installed on the laser telemetry instrument and is used to determine the detection distance between the laser telemetry instrument and the pipeline under inspection. The front-end accelerometer and the rear-end accelerometer are respectively installed at the front and rear ends of the laser telemetry instrument, and are used to detect the acceleration of the front and rear ends of the laser telemetry instrument during the inspection process. The laser telemetry instrument, laser ranging module, front-end accelerometer, and rear-end accelerometer are respectively connected to the main control module. The main control module is used to receive distance data measured by the laser ranging module and acceleration data measured by the front and rear accelerometers, calculate the rotational angular velocity of the laser telemetry instrument and the moving speed of the laser spot of the laser telemetry instrument, and adjust the data refresh rate of the laser telemetry instrument.

5. The laser telemetry instrument according to claim 4, characterized in that: The laser ranging module is located at the left or right front end of the laser telemetry instrument. The ranging beam of the laser ranging module is parallel to the output beam of the laser telemetry instrument.

6. The laser telemetry instrument according to claim 4, characterized in that: Both the front-end and rear-end accelerometers are located on the central axis of the laser telemetry instrument.

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