An automatic reflection multi-point laser ranging method

Abstract

The present invention relates to the field of laser ranging, and discloses an automatic reflection type multi-point laser ranging method, including a measuring host and a measuring point device, wherein the measuring host includes a spherical omnidirectional laser emitting device, a laser receiving device, a wireless communication device and a data processing module; the measuring point device includes a laser receiving device, a laser emitting device and a wireless communication device; the measuring host specifies the measuring point device in turn through wireless communication, emits a laser signal to it, and the measuring point device immediately returns the laser after receiving it, and the measuring host calculates the distance between the host and the measuring point according to the phase difference, thereby realizing automatic measurement of multiple measuring points by one host. The present invention has the advantages of no need for alignment between the host and the measuring point, being suitable for long-distance measurement, and having high efficiency in multi-point measurement, and is suitable for remote monitoring of multiple points such as large buildings, landslides, and large structural parts at the same time, and reduces errors caused by manual operation and measuring point offset.

Description

Technical Field

[0001] The invention relates to the technical field of laser distance measurement, and more specifically to an automatic reflection type multi-point laser distance measurement method. Background Art

[0002] With the continuous advancement of science and technology, distance measurement technology plays a vital role in the fields of construction, aerospace, weather forecasting and engineering measurement. It has the advantages of wide measurement range, high measurement accuracy and fast response speed. However, most of the existing laser distance measurements use single-point measurement methods, which require a certain directionality between the host and the measuring point, or are measured manually point by point. For large structures or long-distance, multi-point measurement scenarios, the existing methods are inefficient, the measurement workload is large, and they are easily affected by factors such as measurement point offset caused by unstable fixed measurement points, making it difficult to guarantee measurement accuracy. When it is necessary to perform multi-point displacement monitoring on large structures such as buildings, landslides, bridges, etc., the traditional laser distance measurement method will be significantly restricted in terms of operation and accuracy. Summary of the invention

[0003] In order to overcome the above-mentioned defects of the prior art, the present invention provides an automatic reflection type multi-point laser ranging method to solve the problems existing in the above-mentioned background technology.

[0004] The present invention provides the following technical solution: an automatic reflection type multi-point laser ranging method, comprising:

[0005] S1: by setting multiple measurement positions in the measurement area and installing measurement point devices, each measurement position is matched with each measurement point device one by one, and each measurement point device is numbered, and at the same time, the measurement host is connected to each measurement point device through a wireless communication network;

[0006] S2: used to control the emission of laser signals. The measuring host specifies the measuring point devices one by one through wireless communication to enter the working state and emit laser signals to them;

[0007] S3: used to receive the laser return signal. When the activated measuring point device receives the laser signal, it immediately sends the laser return signal to the measuring host, and then uses the spatial filtering technology to filter the laser return signal received by the measuring host;

[0008] S4: performing error analysis on the multipath effect of the processed laser signal and calculating a signal error offset value, and monitoring and correcting the error caused by the multipath effect in real time through the signal error offset value;

[0009] S5: Monitor and analyze the phase jump based on the corrected laser signal, and use the unwrap function to process and correct the error caused by the phase jump;

[0010] S6: Based on the phase difference between the laser emitted by the selected measuring point device and the returned laser detected by the measuring host, and combined with the known atmospheric environment parameters for comprehensive analysis, the distance between the measuring host and the single measuring point device is calculated;

[0011] S7: The host computer controls other measuring points in turn to repeat the measuring process of S3 to S6, thereby performing multi-point polling measurement. The host computer displays or transmits the calculated distance information of each measuring point to the upper system, and performs real-time analysis to obtain the distance of the entire measuring area.

[0012] S8: Based on the measured distance of the entire measurement area, abnormal distance changes are detected and warned by setting a normal distance range;

[0013] S9: By monitoring the distance measurement process of the entire measurement area, when all measuring point devices have completed the measurement, the measurement host sends an end command, turns off the measuring point devices and ends the measurement work.

[0014] Preferably, the S1 installs a measuring host in the measurement center area to receive and process the laser signals reflected by each measuring point device. In the measurement area, multiple different measuring positions are selected according to actual needs, and a measuring point device is installed at each measuring position. The installed measuring point devices are numbered 1, 2, ..., n, respectively, for transmitting and receiving the laser signals at each measuring position, and a one-to-one correspondence is established between each measuring position and the corresponding measuring point device;

[0015] The measuring host comprises a spherical omnidirectional laser emitting device, a laser receiving device, a wireless communication device and a data processing module;

[0016] The measuring point device comprises a laser receiving device, a laser emitting device and a wireless communication device, which realizes communication with a host computer and laser round-trip measurement.

[0017] Preferably, the S2 remotely controls each measuring point device through wireless communication based on the measuring host, and sends working instructions to the designated measuring point devices one by one, including starting measurement and adjusting measurement parameters; when the measuring host selects a measuring point device, it sends a working instruction to it, activates the measuring point device, puts it into working state, and emits a laser signal to the selected measuring point device;

[0018] The spherical omnidirectional laser emitting device of the measuring host and the laser receiving device of the measuring point device have relatively wide emitting and receiving viewing angles respectively, and there is no need to deliberately align the measuring host and the measuring point device.

[0019] Preferably, S3 is based on that after the activated measuring point device receives the laser signal, it immediately reflects the laser signal back to the measuring host, and installs a spatial filter on the laser receiving path, allowing the laser signal to pass through the spatial filter and filtering it. When the measuring host receives the reflected laser signal, it converts the laser signal into an electrical signal.

[0020] Preferably, the specific analysis method of the signal error offset value generated by the multipath effect in S4 is:

[0021] Step S411: Assume that the multipath effect is mainly composed of m paths, and the reflection coefficient of each path is ,and , the path length is , the signal attenuation coefficient is , then the analytical calculation formula for the multipath effect error is: , It represents the actual received laser return signal emitted by the i-th measuring point device, and e represents a constant;

[0022] Step S412: Analyze the multipath effect error signal at the current moment The multipath effect error signal at the previous moment The difference between the two is used to calculate the signal error offset value. ;

[0023] By setting the signal error offset value The signal error deviation threshold is set Compare to determine whether error correction is needed. , then the error is considered to be within an acceptable range and there is no need to correct the error of the laser signal. , it is considered that the error exceeds the acceptable range and needs to be corrected. The multipath effect error correction formula is: , It represents the corrected laser signal. The error of the laser signal is corrected and monitored according to the error correction formula.

[0024] Preferably, the S5 extracts phase information from the received laser signal by using a phase detector, processes the phase data using an unwrap function, compensates for the phase jump, and compares the difference between adjacent phase values. If the difference exceeds , it is assumed that wraparound has occurred and the phase value is adjusted accordingly.

[0025] Preferably, the S6 first measures the atmospheric environment parameters that affect the current laser propagation speed, including temperature, humidity and air pressure, and then comprehensively analyzes and calculates the distance between the measuring host and a single measuring point device by using the phase difference data processed by the unwrap function. .

[0026] Preferably, the S7 is performed by the measuring host through which the measuring host can periodically or continuously poll the multiple measuring points, sequentially control the emission and reception operations of the laser signals by other measuring point devices, and repeatedly analyze and calculate the distance between the measuring host and a single measuring point device. For n measuring point devices, the distance of the entire measuring area is represented as a distance vector: .

[0027] Preferably, when the measurement host is performing measurement polling on multiple measurement points, S8 sets a distance change abnormality detection function, and compares the distance of the entire measurement area calculated by the measurement host with a preset normal distance range. If the distance is within the normal range, the distance change continues to be monitored. If the distance is detected to be beyond the normal range, it is determined to be an abnormal distance change, and when an abnormal distance change is detected, a warning message is issued through the alarm system or the remote server.

[0028] Preferably, the S9 monitors in real time the completion signal and status update signal sent by each measuring point to the measuring host after completing the measurement task. When the measuring host confirms that the measurement work of all measuring point devices has been completed, it will automatically generate an end instruction and send it to all measuring point devices through the wireless network. After receiving the end instruction from the host, each measuring point device will execute the shutdown procedure to end the measurement work.

[0029] Technical effects and advantages of the present invention:

[0030] The present invention sets a plurality of measuring positions in a measuring area and installs measuring point devices, makes a one-to-one correspondence between each measuring position and each measuring point device, then establishes a connection between a measuring host and each measuring point device through a wireless communication network, specifies the measuring point devices one by one through wireless communication by the measuring host to enter a working state and emit a laser signal to the measuring point device, and immediately sends a laser return signal to the measuring host after the activated measuring point device receives the laser signal, and then uses a spatial filtering technology to filter the laser return signal received by the measuring host, performs error analysis on the multipath effect of the processed laser signal, calculates the signal error offset value, monitors and corrects the error caused by the multipath effect in real time, and then uses an unwrap function to process and correct the error caused by the phase jump, based on the measurement host detecting the The phase difference between the laser emitted by the selected measuring point device and the returned laser is combined with the known atmospheric environment parameters for comprehensive analysis to calculate the distance between the measuring host and a single measuring point device. The measuring host controls the repeated measurement process of other measuring points in turn, and displays or transmits the calculated distance information of each measuring point to the upper system to obtain the distance of the entire measurement area. Abnormal distance changes are detected and warned by setting a normal distance range. By setting the measuring host and connecting multiple measuring point devices for multi-point laser ranging method, the problem that the traditional laser ranging method is significantly restricted in operation and accuracy can be solved, which is beneficial to improve measurement efficiency and measurement accuracy, thereby reducing the difficulty of measurement, making distance measurement more accurate, and realizing remote and multi-point detection, reducing the uncertainty and errors caused by manual operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a diagram of the method steps of the present invention.

[0032] Figure 2 4 is a system structure block diagram of an embodiment of the present invention.

[0033] Figure 3 It is a schematic diagram of the structure of a measuring host and multiple measuring point devices according to an embodiment of the present invention.

[0034] Figure 4 A schematic diagram of a measurement process according to an embodiment of the present invention. DETAILED DESCRIPTION

[0035] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the present invention. In addition, the forms of the various structures recorded in the following embodiments are merely illustrative. The automatic reflection multi-point laser ranging method involved in the present invention is not limited to the various structures recorded in the following embodiments. All other implementations obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0036] like Figure 1 This embodiment provides an automatic reflection type multi-point laser ranging method, including:

[0037] S1: By setting multiple measurement positions in the measurement area and installing measurement point devices, each measurement position is matched with each measurement point device one by one, and each measurement point device is numbered. At the same time, the measurement host is connected to each measurement point device through a wireless communication network.

[0038] In this embodiment, the S1 installs the measuring host in the measuring center area to receive and process the laser signals reflected by each measuring point device. In the measuring area, multiple different measuring positions are selected according to actual needs, and a measuring point device is installed at each measuring position. The installed measuring point devices are numbered 1, 2, ..., n respectively, for transmitting and receiving the laser signals at each measuring position, and a one-to-one correspondence is established between each measuring position and the corresponding measuring point device;

[0039] The measuring host comprises a spherical omnidirectional laser emitting device, a laser receiving device, a wireless communication device and a data processing module;

[0040] The measuring point device comprises a laser receiving device, a laser emitting device and a wireless communication device, which realizes communication with a host computer and laser round-trip measurement.

[0041] It should be specifically explained that the measuring host is installed in the measuring center area. The host is equipped with a spherical omnidirectional laser transmitting device, a laser receiving device, a wireless communication device and a data processing module. The wireless communication device of the measuring host and the measuring point device adopts a low-power wireless network or other long-distance wireless communication method, so that the measuring point device can be in a sleep or low-power state when not measuring.

[0042] S2: Used to control the emission of laser signals. The measuring host uses wireless communication to specify the measuring point devices one by one to enter the working state and emit laser signals to them.

[0043] In this embodiment, the S2 remotely controls each measuring point device through wireless communication based on the measuring host, and sends working instructions to the designated measuring point devices one by one, including starting measurement and adjusting measurement parameters; when the measuring host selects a measuring point device, it sends a working instruction to it, activates the measuring point device, puts it into working state, and emits a laser signal to the selected measuring point device;

[0044] The spherical omnidirectional laser emitting device of the measuring host and the laser receiving device of the measuring point device have relatively wide emitting and receiving viewing angles respectively, and there is no need to deliberately align the measuring host and the measuring point device.

[0045] It should be specifically explained that after the measuring host and the measuring point are powered on, the connection confirmation is completed through wireless communication, and the address or serial number of each measuring point is identified. The measuring host specifies the measuring point device that needs to work through wireless communication according to the pre-set measurement sequence or real-time needs. Finally, the measuring host emits a laser to the measuring point, and the measuring point immediately emits a laser back after receiving it. The host receives the returned laser signal. Through one host, lasers can be emitted to multiple measuring points and measured respectively, which greatly improves the measurement efficiency. There is no need for special angle alignment between the host and the measuring point. It only needs to ensure that the measuring point can receive the laser and can emit it back. At the same time, using wireless communication, the host can remotely control the sleep and working status of multiple measuring points, which is more energy-saving and efficient.

[0046] S3: used to receive the laser return signal. When the activated measuring point device receives the laser signal, it immediately sends the laser return signal to the measuring host, and then uses the spatial filtering technology to filter the laser return signal received by the measuring host.

[0047] In this embodiment, after the activated measuring point device receives the laser signal, S3 immediately reflects the laser signal back to the measuring host, and installs a spatial filter on the laser receiving path to allow the laser signal to pass through the spatial filter for filtering. When the measuring host receives the reflected laser signal, it converts the laser signal into an electrical signal.

[0048] It should be specifically noted that the specific operation steps for transmitting and receiving laser signals include:

[0049] Step 1: The measuring host transmits a laser signal to the first measuring point device that enters the working state;

[0050] Step 2: After receiving the laser signal, the measuring point device immediately reflects the signal back to the measuring host;

[0051] Step 3: The measuring host records the round trip time of the laser signal.

[0052] S4: Based on the error analysis of the multipath effect of the processed laser signal, a signal error offset value is calculated, and the error caused by the multipath effect is monitored and corrected in real time through the signal error offset value.

[0053] In this embodiment, the specific analysis method of the signal error offset value generated by the multipath effect in S4 is:

[0054] Step S411: Assume that the multipath effect is mainly composed of m paths, and the reflection coefficient of each path is ,and , the path length is , the signal attenuation coefficient is , then the analytical calculation formula for the multipath effect error is: , It represents the actual received laser return signal emitted by the i-th measuring point device, and e represents a constant;

[0055] Step S412: Analyze the multipath effect error signal at the current moment The multipath effect error signal at the previous moment The difference between the two is used to calculate the signal error offset value. ;

[0056] By setting the signal error offset value The signal error deviation threshold is set Compare to determine whether error correction is needed. , then the error is considered to be within an acceptable range and there is no need to correct the error of the laser signal. , it is considered that the error exceeds the acceptable range and needs to be corrected. The multipath effect error correction formula is: , It represents the corrected laser signal. The error of the laser signal is corrected and monitored according to the error correction formula.

[0057] S5: Monitor and analyze phase jumps based on the corrected laser signal, and use the unwrap function to process and correct the errors caused by phase jumps.

[0058] In this embodiment, the S5 extracts phase information from the received laser signal by using a phase detector, processes the phase data using an unwrap function, compensates for the phase jump, and compares the difference between adjacent phase values. If the difference exceeds , it is assumed that wraparound has occurred and the phase value is adjusted accordingly.

[0059] It should be specifically noted that a suitable unwrap algorithm, such as Hilbertunwrap, Gaussianunwrap or path-based unwrap algorithm, is selected, the parameters of the unwrap function are initialized, the phase data is analyzed, and the phase jump points, i.e., the discontinuity points in the phase data, are detected; the detected phase jumps are unwrapped, and a threshold is set to determine whether the phase change exceeds 2 For each data point, the phase change between it and the previous data point is calculated, and the phase jump across 2 is determined. According to the calculated jump times, the phase value is corrected, that is, adding or subtracting 2 at each jump point. to restore the phase continuity.

[0060] S6: Based on the phase difference between the laser emitted by the selected measuring point device and the returned laser detected by the measuring host, and combined with comprehensive analysis using known atmospheric environmental parameters, the distance between the measuring host and a single measuring point device is calculated.

[0061] In this embodiment, the S6 first measures the atmospheric environment parameters that affect the current laser propagation speed, including temperature, humidity and air pressure, and then comprehensively analyzes and calculates the distance between the measuring host and a single measuring point device by using the phase difference data processed by the unwrap function. .

[0062] It should be specifically noted that, based on the atmospheric environment parameters and the corrected phase difference data, the specific analysis method for the distance between the measuring host and a single measuring point device is as follows:

[0063] Step 1: Based on the measured current atmospheric environment parameters, analyze and calculate the influence factor of atmospheric refractive index on laser signal: , represents the standard atmospheric refractive index, T represents temperature, and P represents air pressure. Indicates humidity, is the weight coefficient;

[0064] Step 2: By measuring the phase difference between the transmitted signal and the received signal If there is a phase jump, use the unwrap function to process the phase jump and get the corrected phase difference as ;

[0065] Step 3: Combine the phase difference after unwrap function processing and the atmospheric refractive index compensation factor to calculate the distance between the measurement host and a single measuring point device: , represents the wavelength of the laser emitted by the i-th measuring point device, Represents the corrected phase difference between the i-th transmitted signal and the received signal.

[0066] S7: The host computer controls other measuring points in turn to repeat the measuring process of S3 to S6, thereby performing multi-point polling measurement. The host computer displays or transmits the calculated distance information of each measuring point to the upper system, and performs real-time analysis to obtain the distance of the entire measuring area.

[0067] In this embodiment, the S7 is performed by the measuring host through which the measuring host can periodically or continuously poll multiple measuring points, sequentially control the emission and reception operations of laser signals by other measuring point devices, and repeatedly analyze and calculate the distance between the measuring host and a single measuring point device. For n measuring point devices, the distance of the entire measuring area is represented as a distance vector: .

[0068] S8: Based on the measured distance of the entire measurement area, abnormal distance changes are detected and warned by setting a normal distance range.

[0069] In this embodiment, when the measurement host is performing measurement polling on multiple measurement points, S8 sets a distance change abnormality detection function. By comparing the distance of the entire measurement area calculated by the measurement host with a preset normal distance range, if the distance is within the normal range, the distance change continues to be monitored. If it is detected that the distance exceeds the normal range, it is determined to be an abnormal distance change. When an abnormal distance change is detected, an early warning message is issued through the alarm system or remote server.

[0070] In this embodiment, the S9 monitors in real time the completion signal and status update signal sent by each measuring point to the measurement host after completing the measurement task. When the measurement host confirms that the measurement work of all measuring point devices has been completed, it will automatically generate an end instruction and send it to all measuring point devices through the wireless network. After receiving the end instruction from the host, each measuring point device will execute the shutdown procedure to end the measurement work.

[0071] It should be specifically noted that this method is suitable for long-distance and multi-point displacement monitoring of large buildings, landslides, large structural parts, etc. Since the measuring points are fixedly installed, the errors caused by manual movement or handheld measuring instruments are reduced, significantly improving the measurement accuracy and stability.

[0072] like Figure 2The embodiment shown provides an implementation system corresponding to an anti-counterfeiting method for articles based on local feature visual information, including a measurement deployment module, a signal transmission control module, a signal receiving module, a signal error correction module, a phase error correction module, a measurement distance analysis module, a multi-point polling measurement execution module, an abnormal distance detection module and a measurement end closing module, wherein the measurement deployment module is connected to the signal transmission control module, the signal transmission control module is connected to the signal receiving module, the signal receiving module is connected to the signal error correction module, the signal receiving module is connected to the phase error correction module, the signal error correction module is connected to the measurement distance analysis module, the phase error correction module is connected to the measurement distance analysis module, the measurement distance analysis module is connected to the multi-point polling measurement execution module, the multi-point polling measurement execution module is connected to the abnormal distance detection module, and the abnormal distance detection module is connected to the measurement end closing module.

[0073] The measurement deployment module sets a plurality of measurement positions in the measurement area and installs measurement point devices, corresponds each measurement position to each measurement point device one by one, and numbers each measurement point device. At the same time, the measurement host establishes a connection with each measurement point device through a wireless communication network;

[0074] The signal emission control module is used to control the emission of laser signals. The measuring host specifies the measuring point devices one by one through wireless communication to enter the working state and emit laser signals to them.

[0075] The signal receiving module is used to receive the laser return signal. When the activated measuring point device receives the laser signal, it immediately sends the laser return signal to the measuring host, and then uses the spatial filtering technology to filter the laser return signal received by the measuring host;

[0076] The signal error correction module performs error analysis on the multipath effect of the processed laser signal and calculates a signal error offset value, and monitors and corrects the error caused by the multipath effect in real time through the signal error offset value;

[0077] The phase error correction module monitors and analyzes phase jumps based on the corrected laser signal, and uses the unwrap function to process and correct the error caused by the phase jump;

[0078] The measuring distance analysis module calculates the distance between the measuring host and a single measuring point device based on the phase difference between the laser emitted by the selected measuring point device and the returned laser detected by the measuring host and a comprehensive analysis using known atmospheric environment parameters;

[0079] The multi-point polling measurement execution module controls other measuring points in turn through the measuring host to repeat the measurement process from S3 to S6, thereby performing multi-point polling measurement. The host displays or transmits the calculated distance information of each measuring point to the upper system, and performs real-time analysis to obtain the distance of the entire measuring area.

[0080] The abnormal distance detection module detects and warns abnormal distance changes by setting a normal distance range based on the measured distance of the entire measurement area;

[0081] The measurement end closing module monitors the distance measurement process of the entire measurement area. When all the measuring point devices have completed the measurement, the measurement host sends an end instruction to close the measuring point devices and end the measurement work.

[0082] like Figure 3 The embodiment shown provides a connection structure between a measuring host and multiple measuring point devices, including a host device and a measuring point device. The specific device structure and operation process are as follows:

[0083] Host device:

[0084] (1) Spherical omnidirectional laser emitting device: ensures that the laser is emitted over a wide range so that multiple dispersed measuring points can receive the laser beam without manual alignment;

[0085] (2) Laser receiving device: used to receive the laser signal reflected back from the measuring point; this device can adopt an omnidirectional or wide-angle receiving design;

[0086] (3) Wireless communication device: connected to the wireless communication unit of each measuring point, used to control the start-up of the measuring point, data transmission and receiving working status feedback of the measuring point;

[0087] (4) Data processing module: It calculates the emission time, return time, and phase difference of the laser signal, calculates the distance between the host and the measuring point, and can perform error compensation and data recording according to specific algorithms;

[0088] Measuring point device:

[0089] (1) Laser receiving device: receives laser signals from the host;

[0090] (2) Laser emitting device: after receiving the laser signal at the measuring point, it immediately returns the laser to the host;

[0091] (3) Wireless communication device: communicates with the host, receives commands from the host, and transmits its own working status and laser signal interaction information to the host;

[0092] (4) Power management module: The measurement point can be put into sleep mode during non-measurement period to save energy.

[0093] like Figure 4 The present embodiment provides a measurement process of an automatic reflection type multi-point laser ranging method, comprising the following steps:

[0094] Step 1: Wake up the designated measuring point through the measuring host and put the designated measuring point device into working state;

[0095] Step 2: The measuring host transmits a laser signal with modulation information to the designated measuring point device;

[0096] Step 3: It is used to receive the laser signal sent by the measuring host. When the measuring point receives the signal, it immediately sends a laser return signal.

[0097] Step 4: Amplify the laser signal through the measuring point and return it to the measuring host;

[0098] Step 5: The phase difference of the signal transmitted by the measuring point measured and received by the measuring host;

[0099] Step 6: Calculate the distance between the measuring point and the host by measuring the host;

[0100] Step 7: After calculating the distance between the measuring point and the host, the measuring host immediately sends a command to turn off the measuring point laser;

[0101] Step 8: After the measuring point device receives the instruction, the laser ranging of the measuring point device is terminated, and the measurement of the next measuring point is started.

[0102] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

[0103] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An automatic reflection multi-point laser ranging method, characterized in that: include: S1: by setting multiple measurement positions in the measurement area and installing measurement point devices, each measurement position is matched with each measurement point device one by one, and each measurement point device is numbered, and at the same time, the measurement host is connected to each measurement point device through a wireless communication network; S2: used to control the emission of laser signals. The measuring host specifies the measuring point devices one by one through wireless communication to enter the working state and emit laser signals to them; S3: used to receive the laser return signal. When the activated measuring point device receives the laser signal, it immediately sends the laser return signal to the measuring host, and then uses the spatial filtering technology to filter the laser return signal received by the measuring host; S4: performing error analysis on the multipath effect of the processed laser signal and calculating a signal error offset value, and monitoring and correcting the error caused by the multipath effect in real time through the signal error offset value; S5: Monitor and analyze the phase jump based on the corrected laser signal, and use the unwrap function to process and correct the error caused by the phase jump; S6: Based on the phase difference between the laser emitted by the selected measuring point device and the returned laser detected by the measuring host, and combined with the known atmospheric environment parameters for comprehensive analysis, the distance between the measuring host and the single measuring point device is calculated; S7: The host computer controls other measuring points in turn to repeat the measuring process of S3 to S6, thereby performing multi-point polling measurement. The host computer displays or transmits the calculated distance information of each measuring point to the upper system, and performs real-time analysis to obtain the distance of the entire measuring area. S8: Based on the measured distance of the entire measurement area, abnormal distance changes are detected and warned by setting a normal distance range; S9: By monitoring the distance measurement process of the entire measurement area, when all measuring point devices have completed the measurement, the measurement host sends an end command, turns off the measuring point devices and ends the measurement work.

2. The automatic reflection type multi-point laser ranging method according to claim 1, characterized in that: The S1 installs the measuring host in the measuring center area to receive and process the laser signals reflected by each measuring point device. In the measuring area, multiple different measuring positions are selected according to actual needs, and a measuring point device is installed at each measuring position. The installed measuring point devices are numbered 1, 2, ..., n respectively, for transmitting and receiving the laser signals at each measuring position, and a one-to-one correspondence is established between each measuring position and the corresponding measuring point device; The measuring host comprises a spherical omnidirectional laser emitting device, a laser receiving device, a wireless communication device and a data processing module; The measuring point device comprises a laser receiving device, a laser emitting device and a wireless communication device, which realizes communication with a host computer and laser round-trip measurement.

3. The automatic reflection type multi-point laser ranging method according to claim 1, characterized in that: The S2 remotely controls each measuring point device through wireless communication based on the measuring host, and sends working instructions to the designated measuring point devices one by one, including starting measurement and adjusting measurement parameters; when the measuring host selects a measuring point device, it sends a working instruction to it, activates the measuring point device, puts it into working state, and emits a laser signal to the selected measuring point device; The spherical omnidirectional laser emitting device of the measuring host and the laser receiving device of the measuring point device have relatively wide emitting and receiving viewing angles respectively, and there is no need to deliberately align the measuring host and the measuring point device.

4. The automatic reflection type multi-point laser ranging method according to claim 1, characterized in that: The S3 is based on the activated measuring point device receiving the laser signal, immediately reflecting the laser signal back to the measuring host, and installing a spatial filter on the laser receiving path, allowing the laser signal to pass through the spatial filter and filtering it. When the measuring host receives the reflected laser signal, it converts the laser signal into an electrical signal.

5. The automatic reflection type multi-point laser ranging method according to claim 1, characterized in that: The specific analysis method of the signal error offset value generated by the multipath effect in S4 is as follows: Step S411: Assume that the multipath effect is mainly composed of m paths, and the reflection coefficient of each path is ,and , the path length is , the signal attenuation coefficient is , then the analytical calculation formula for the multipath effect error is: , It represents the actual received laser return signal emitted by the i-th measuring point device, and e represents a constant; Step S412: Analyze the multipath effect error signal at the current moment The multipath effect error signal at the previous moment The difference between the two is used to calculate the signal error offset value. ; By setting the signal error offset value The signal error deviation threshold is set Compare to determine whether error correction is needed. , then the error is considered to be within an acceptable range and there is no need to correct the error of the laser signal. , it is considered that the error exceeds the acceptable range and needs to be corrected. The multipath effect error correction formula is: , It represents the corrected laser signal. The error of the laser signal is corrected and monitored according to the error correction formula.

6. The automatic reflection type multi-point laser ranging method according to claim 1, characterized in that: The S5 extracts phase information from the received laser signal by using a phase detector, processes the phase data using an unwrap function, and compensates for phase jumps by comparing the difference between adjacent phase values. If the difference exceeds , it is assumed that wraparound has occurred and the phase value is adjusted accordingly.

7. The automatic reflection type multi-point laser ranging method according to claim 1, characterized in that: The S6 first measures the atmospheric environment parameters that affect the current laser propagation speed, including temperature, humidity and air pressure, and then uses the phase difference data processed by the unwrap function to comprehensively analyze and calculate the distance between the measurement host and a single measurement point device. .

8. The automatic reflection type multi-point laser ranging method according to claim 1, characterized in that: The S7 is performed by the measuring host through which the measuring host can periodically or continuously poll multiple measuring points, control the emission and reception of laser signals by other measuring point devices in turn, and repeatedly analyze and calculate the distance between the measuring host and a single measuring point device. For n measuring point devices, the distance of the entire measuring area is expressed as a distance vector: .

9. The automatic reflection type multi-point laser ranging method according to claim 1, characterized in that: In S8, when the measurement host is performing measurement polling on multiple measurement points, the distance change abnormality detection function is set to compare the distance of the entire measurement area calculated by the measurement host with the preset normal distance range. If the distance is within the normal range, the distance change continues to be monitored. If the distance is detected to be beyond the normal range, it is determined to be an abnormal distance change, and when an abnormal distance change is detected, a warning message is issued through the alarm system or the remote server.

10. The automatic reflection type multi-point laser ranging method according to claim 1, characterized in that: The S9 monitors in real time the completion signal and status update signal sent by each measuring point to the measuring host after completing the measurement task. When the measuring host confirms that the measurement work of all measuring point devices has been completed, it will automatically generate an end instruction and send it to all measuring point devices through the wireless network. After receiving the end instruction from the host, each measuring point device will execute the shutdown procedure to end the measurement work.

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