Tower crane lifting height compensation method and device based on RTK positioning system

Abstract

The invention provides a tower crane lifting height compensation method and device based on an RTK positioning system, and particularly relates to the technical field of safety monitoring of tower cranes. According to the method, a base station is installed on a ground datum point, a mobile station is installed on a lifting hook connecting plate, and a wireless communication module is used for connection to form an RTK positioning system. The system can acquire the first height data of the lifting hook in real time, and combines the second height data of the encoder of the hoisting mechanism of the tower crane. When the tower crane is no-load, calculating the deviation of the two data to obtain an initial compensation parameter; and during loading, according to the hook displacement variation measured by the RTK system and the initial compensation parameter, generating a dynamic compensation amount, superposing the dynamic compensation amount to the second height data, and outputting the compensated hook height. According to the method, the problem of dynamic errors caused by elastic deformation of the cantilever crane is effectively solved, the measurement precision is remarkably improved, the traditional measurement limitation in a severe environment is broken through, all-weather stable monitoring is achieved, structural transformation is not needed, and a solid guarantee is provided for high-altitude operation safety.

Description

Technical Field

[0001] The invention relates to the technical field of tower crane safety monitoring, and in particular to a tower crane lifting height compensation method and device based on an RTK positioning system. Background Art

[0002] In recent years, with the increase in super-high-rise buildings and large-scale infrastructure projects, tower crane hoisting heights exceeding 300 meters have become the norm, placing higher requirements on the accuracy of hook height measurement. However, the elastic deformation of the tower crane boom under load (maximum deflection of 2 meters) causes the traditional measurement system to have "inaccurate measurement" phenomenon, which can easily lead to component installation dislocation and collision risks, becoming the core bottleneck restricting the safety upgrade of intelligent construction.

[0003] The existing technology mainly measures the length of the wire rope to calculate the height through the gear encoder, but it cannot perceive the actual displacement of the suspension point caused by the deformation of the boom; although the visual recognition solution can capture the hook position, the recognition accuracy drops sharply under working conditions such as strong light glare, rain, snow, fog and haze. Both lack the ability to compensate for dynamic deformation in real time, resulting in an exponential increase in height error as the load increases.

[0004] In summary, how to solve the technical problem of dynamic error compensation caused by the elastic deformation of the boom in the hook height measurement of the tower crane is an issue that needs to be solved urgently. Summary of the invention

[0005] The main purpose of the present invention is to provide a tower crane lifting height compensation method and device based on an RTK positioning system to solve the technical problem of dynamic error compensation caused by the elastic deformation of the boom in the existing tower crane hook height measurement, thereby significantly improving the measurement accuracy of the tower crane hook height by dynamically compensating for the elastic deformation of the boom, breaking through the limitations of traditional methods in harsh environments, achieving all-weather stable monitoring, and avoiding the need for structural modification, providing reliable protection for the safety of high-altitude operations.

[0006] In order to achieve the above object, the present invention provides a tower crane lifting height compensation method and device based on an RTK positioning system.

[0007] In a first aspect, the present invention provides a tower crane lifting height compensation method based on an RTK positioning system, the method comprising:

[0008] A reference station is installed at a ground reference point, and a mobile station is installed on a hook connection plate. The reference station and the mobile station are connected via a wireless communication module to form an RTK positioning system.

[0009] The first height data of the hook is obtained by the RTK positioning system, and the second height data of the length of the wire rope is obtained by the encoder of the tower crane hoisting mechanism;

[0010] When the tower crane is in an unloaded state, calculating an initial compensation parameter based on a deviation value between the first height data and the second height data;

[0011] Under the load state of the tower crane, a dynamic compensation amount is generated according to the hook displacement change measured in real time by the RTK positioning system and the initial compensation parameter;

[0012] The dynamic compensation amount is superimposed on the second height data to output a compensated hook height measurement value.

[0013] Optionally, the step of installing a reference station at a ground reference point and installing a mobile station at a hook connection plate comprises:

[0014] Install the reference station at the ground reference point 20-50 meters away from the center of the tower crane;

[0015] The mobile station is fixed to the hook connecting plate by a magnetic fixer.

[0016] Optionally, the calculating of the initial compensation parameter based on the deviation value between the first height data and the second height data when the tower crane is in an unloaded state includes:

[0017] When the tower crane is unloaded and the boom is at a horizontal reference position, synchronously recording the first height data and the second height data;

[0018] A deviation value between the first height data and the second height data is calculated according to the first height data and the second height data as the initial compensation parameter.

[0019] Optionally, generating a dynamic compensation amount according to a hook displacement change measured in real time by the RTK positioning system and the initial compensation parameter under a tower crane load state includes:

[0020] Processing the three-dimensional coordinate data of the hook continuously collected by the RTK positioning system through a Kalman filter algorithm;

[0021] The displacement component perpendicular to the ground is extracted according to the three-dimensional coordinate data of the hook, and the dynamic compensation amount is generated in combination with the initial compensation parameters.

[0022] Optionally, superimposing the dynamic compensation amount onto the second height data and outputting a compensated hook height measurement value comprises:

[0023] The dynamic compensation amount and the second height data are input into a data processing module, and a compensated hook height measurement value is output through a preset weight distribution algorithm in the data processing module.

[0024] Optionally, the wireless communication module adopts the LoRa communication protocol.

[0025] In a second aspect, the present invention provides a tower crane lifting height compensation device based on an RTK positioning system, the compensation device is applied to the tower crane lifting height compensation method based on an RTK positioning system in the first aspect, and the compensation device comprises:

[0026] A positioning system deployment unit, the positioning system deployment unit is used to install a reference station at a ground reference point and a mobile station at a hook connection plate, the reference station and the mobile station are connected via a wireless communication module to form an RTK positioning system;

[0027] A dual-source data acquisition unit, the dual-source data acquisition unit is connected to the positioning system deployment unit, and the dual-source data acquisition unit is used to obtain first height data of the hook through the RTK positioning system, and obtain second height data of the length of the wire rope retracted and released through an encoder of the tower crane hoisting mechanism;

[0028] An empty reference calibration unit, the empty reference calibration unit is connected to the dual-source data acquisition unit, and the empty reference calibration unit is used to calculate an initial compensation parameter based on a deviation value between the first height data and the second height data when the tower crane is in an empty state;

[0029] A dynamic deformation compensation unit, the dynamic deformation compensation unit is connected to the no-load reference calibration unit, and the dynamic deformation compensation unit is used to generate a dynamic compensation amount according to the hook displacement change measured in real time by the RTK positioning system and the initial compensation parameter under the load state of the tower crane;

[0030] A fusion data output unit is connected to the dynamic deformation compensation unit, and is used to superimpose the dynamic compensation amount on the second height data to output a compensated hook height measurement value.

[0031] Optionally, the positioning system deployment unit includes:

[0032] A reference station installation module, the reference station installation module is used to install the reference station at the ground reference point set at 20-50 meters away from the center point of the tower crane tower;

[0033] A mobile station installation module, the mobile station installation module is connected to the base station installation module, and the mobile station installation module is used to fix the mobile station to the hook connection plate through a magnetic fixer.

[0034] Optionally, the no-load reference calibration unit comprises:

[0035] An unloaded data acquisition module, wherein the unloaded data acquisition module is used to synchronously record the first height data and the second height data when the tower crane is unloaded and the boom is at a horizontal reference position;

[0036] An initial compensation parameter acquisition module, wherein the initial compensation parameter acquisition module is connected to the no-load data acquisition module, and the initial compensation parameter acquisition module is used to calculate a deviation value between the first height data and the second height data as the initial compensation parameter.

[0037] Optionally, the dynamic deformation compensation unit includes:

[0038] A three-dimensional coordinate data acquisition module, which is used to process the three-dimensional coordinate data of the hook continuously collected by the RTK positioning system through a Kalman filter algorithm;

[0039] A dynamic compensation acquisition module is connected to the three-dimensional coordinate data acquisition module, and is used to extract the displacement component perpendicular to the ground according to the three-dimensional coordinate data of the hook, and generate the dynamic compensation amount in combination with the initial compensation parameters.

[0040] The present application provides a tower crane lifting height compensation method and device based on the RTK positioning system. The method sets a reference station on the ground, installs a mobile station on the hook connecting plate, and connects the two via a wireless communication module to form an RTK positioning system. The system can obtain the first height data of the hook in real time, and the encoder of the tower crane hoisting mechanism provides the second height data of the length of the wire rope. When the tower crane is unloaded, the initial compensation parameters are calculated based on the deviation of the two data; when loaded, the dynamic compensation amount is generated by combining the hook displacement change measured in real time by the RTK system with the initial compensation parameters, and superimposed on the second height data to obtain the compensated hook height. This method effectively solves the problem of dynamic errors caused by the elastic deformation of the boom, significantly improves the measurement accuracy, breaks through the limitations of traditional methods in harsh environments, realizes all-weather stable monitoring, does not require structural modification, and provides a strong guarantee for the safety of high-altitude operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0042] Figure 1 A flow chart of a tower crane lifting height compensation method based on an RTK positioning system provided in this application;

[0043] Figure 2 A connection diagram of a tower crane lifting height compensation device based on an RTK positioning system provided in this application;

[0044] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in this application will be clearly and completely described below in conjunction with the drawings in this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0046] The terms "first", "second", "third", "fourth", etc. in the specification and claims of the present invention and the above-mentioned drawings, if present, are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in sequences other than those illustrated or described herein.

[0047] In the present invention, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in this application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0048] In response to the above problems, the present application provides a tower crane lifting height compensation method and device based on the RTK positioning system, which aims to solve the dynamic error problem caused by the elastic deformation of the boom in the tower crane hook height measurement. This method forms an RTK positioning system by installing a base station and a mobile station, and combines the encoder data of the tower crane hoisting mechanism to calculate the initial compensation parameters when it is unloaded. When loaded, it generates a dynamic compensation amount based on the real-time displacement change and the initial parameters, and superimposes it on the height data to output the compensated hook height. This method significantly improves the measurement accuracy, breaks through the limitations of harsh environments, realizes all-weather stable monitoring, does not require structural modification, and provides reliable technical guarantees for the safety of high-altitude operations.

[0049] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0050] Figure 1 The present invention provides a flow chart of the tower crane lifting height compensation method based on the RTK positioning system, and describes the tower crane lifting height compensation method based on the RTK positioning system in detail. Figure 1 As shown, the tower crane lifting height compensation method based on the RTK positioning system provided in this embodiment includes:

[0051] S101: Install a reference station at a ground reference point, and install a mobile station on a hook connection plate. The reference station and the mobile station are connected via a wireless communication module to form an RTK positioning system.

[0052] Specifically, the step of installing the reference station at the ground reference point and installing the mobile station at the hook connecting plate includes: installing the reference station at the ground reference point 20-50 meters away from the center point of the tower crane; and fixing the mobile station to the hook connecting plate through a magnetic fixer.

[0053] Specifically, the wireless communication module adopts the LoRa communication protocol.

[0054] During the specific implementation, a GNSS base station receiver is installed at the ground reference point, and a GNSS mobile station receiver is installed on the hook connection plate. The base station is installed at a pre-buried concrete base ground reference point 30 meters away from the center of the tower crane (the allowable installation distance range is 20-50 meters), and the base station receiver is rigidly connected to the ground reference point through M12 expansion bolts. The mobile station receiver is adsorbed on the surface of the hook connection plate through a magnetic fixture. The magnetic fixture contains 4 groups of neodymium iron boron permanent magnet arrays, and the magnetic attraction of each group of magnets is 300N, ensuring that the mobile station does not move during the movement of the hook. A wireless communication link is established between the base station receiver and the mobile station receiver through the LoRa wireless communication module. The operating frequency of the LoRa wireless communication module is set to 868MHz, the transmission power is set to 20dBm, the bandwidth is configured to 125kHz, the spread factor is set to 9, and the data packet length is fixed to 128 bytes. The base station receiver has a built-in dual-frequency GNSS board, and the mobile station receiver has a built-in dual-frequency GNSS board. The two form a real-time dynamic RTK positioning system through carrier phase differential technology. During the system initialization phase, the WGS84 coordinate system of the base station coordinates must be accurately measured, and the measurement error must be controlled within the range of ±2cm. After the installation is completed, the operator needs to verify the fixed solution status of the RTK positioning system. When the positioning mode identifier displayed by the mobile station receiver continues to remain in the "FIXED" state for more than 30 seconds, the RTK positioning system is considered to be completed.

[0055] S102: Acquire first height data of the hook through the RTK positioning system, and acquire second height data of the length of the wire rope retracted and released through the encoder of the tower crane hoisting mechanism.

[0056] In step S102, the process of obtaining the first height data of the hook through the RTK positioning system and obtaining the second height data of the length of the wire rope retracted and released through the encoder of the tower crane hoisting mechanism is implemented. The following are the specific implementation details of this step:

[0057] 1. RTK positioning system obtains the first height data of the hook

[0058] RTK positioning system composition: First, ensure that the base station has been installed at the ground reference point, the mobile station has been installed on the hook connection plate, and the two are connected through the LoRa wireless communication module to form a complete RTK positioning system.

[0059] Data collection: Start the RTK positioning system. The base station sends differential signals to the mobile station through the LoRa communication protocol. After receiving the differential signals, the mobile station performs real-time carrier phase differential calculation to obtain high-precision three-dimensional coordinate data of the hook.

[0060] Height data extraction: Extract the vertical height of the hook relative to the ground, i.e., the first height data, from the three-dimensional coordinate data of the hook calculated by the mobile station.

[0061] 2. The encoder of the tower crane hoisting mechanism obtains the second height data of the wire rope retraction and release length

[0062] Encoder installation: The wire rope of the tower crane hoisting mechanism is wound on the drum, and the encoder is connected to the drum shaft to record the number and direction of rotation of the drum.

[0063] Data reading: When the hoisting mechanism is working, the encoder records the rotation information of the drum in real time and converts it into the retracted length of the wire rope. Since there is a fixed proportional relationship between the retracted length of the wire rope and the vertical lifting height of the hook (considering the multiplier of the pulley block), the second height data of the hook can be obtained by calculation.

[0064] Height data calculation: According to the encoder pulse number (or rotation angle) and the wire rope diameter, pulley ratio and other parameters, the second height data of the hook is calculated by the following formula:

[0065] Assuming that the change in wire rope length corresponding to each rotation of the encoder is L (the actual length change after considering the pulley group ratio), the current pulse number of the encoder is P, and the initial pulse number is P0, then the retracted and released length of the wire rope is ΔL=(P-P0)*L.

[0066] Since ΔL is the change in the vertical lifting height of the hook relative to the initial position, the second height data = initial height + ΔL. The initial height refers to the vertical height of the tower crane hook relative to the ground at a specific moment (usually when the measurement starts or the tower crane is unloaded and the boom is in a horizontal reference position). Specifically, when the tower crane is unloaded and the boom is in a horizontal reference position, the hook height at this time will be recorded as the initial height. Subsequently, when the tower crane starts working and the hook is lifted or lowered, the encoder will measure the retracted and released length of the wire rope (ΔL), and add it to the initial height to obtain the current second height data of the hook.

[0067] S103: When the tower crane is in an unloaded state, calculating an initial compensation parameter based on a deviation value between the first height data and the second height data.

[0068] Specifically, the initial compensation parameter is calculated based on the deviation value between the first height data and the second height data when the tower crane is in an unloaded state, including: when the tower crane is unloaded and the boom is in a horizontal reference position, the first height data and the second height data are synchronously recorded; and the deviation value between the first height data and the second height data is calculated as the initial compensation parameter.

[0069] In step S103, when implementing the step, we need to calculate the initial compensation parameters based on the deviation between the first height data obtained by the RTK positioning system and the second height data obtained by the encoder of the tower crane hoisting mechanism when the tower crane is in an unloaded state. The following are the specific implementation details of this step:

[0070] 1. Confirmation of the no-load state of the tower crane and the horizontal reference position of the crane arm

[0071] Tower crane no-load state: Make sure there is no load on the tower crane, that is, no heavy objects are hung under the hook.

[0072] Horizontal reference position of the boom: adjust the boom to a horizontal position through the tower crane control system or manual operation, and confirm that it is in a stable state. At this time, the angle between the boom and the ground should be 0 degrees or close to 0 degrees.

[0073] 2. Synchronously record the first height data and the second height data

[0074] Start the RTK positioning system: Make sure the base station and the mobile station are correctly installed and connected, start the RTK positioning system, and let it start collecting the three-dimensional coordinate data of the hook in real time.

[0075] Read encoder data: At the same time, the retracted and released length of the wire rope is read through the encoder of the tower crane hoisting mechanism, which reflects the vertical lifting or lowering height of the hook relative to the initial position.

[0076] Synchronous recording: When the boom is in the horizontal reference position and the tower crane remains unloaded, the first height data output by the RTK positioning system (i.e. the vertical height of the hook) and the second height data output by the encoder are synchronously recorded.

[0077] 3. Calculate the deviation value as the initial compensation parameter

[0078] Data alignment: Ensure that the recorded first height data and the second height data are aligned in time, that is, they reflect the hook height at the same moment.

[0079] Deviation value calculation: Calculate the deviation value between the first height data and the second height data. This can be achieved by a simple subtraction operation: deviation value = first height data - second height data.

[0080] Determine the initial compensation parameter: Save the calculated deviation value as the initial compensation parameter. This parameter is used to perform dynamic compensation on the second height data in the tower crane load state.

[0081] Through the above steps, we successfully calculated the initial compensation parameters when the tower crane was unloaded. This parameter is the key to achieving high-precision hook height measurement in the future, and can effectively compensate for dynamic errors caused by factors such as elastic deformation of the boom.

[0082] S104: Under the tower crane load state, a dynamic compensation amount is generated according to the hook displacement change measured in real time by the RTK positioning system and the initial compensation parameter.

[0083] Specifically, when the tower crane is in a loaded state, a dynamic compensation amount is generated based on the hook displacement change measured in real time by the RTK positioning system and the initial compensation parameters, including: processing the three-dimensional coordinate data of the hook continuously collected by the RTK positioning system through a Kalman filter algorithm; extracting the displacement component perpendicular to the ground based on the three-dimensional coordinate data of the hook, and generating a dynamic compensation amount in combination with the initial compensation parameters.

[0084] In step S104, our goal is to generate dynamic compensation based on the hook displacement change measured in real time by the RTK positioning system and the initial compensation parameters under the tower crane load state. The following are the specific implementation details of this step:

[0085] 1. Real-time data collection of RTK positioning system

[0086] Start the RTK positioning system: Make sure the base station and mobile station have been correctly installed and connected, start the RTK positioning system, and let it start collecting the three-dimensional coordinate data of the hook in real time. These data include the longitude, latitude and altitude information of the hook.

[0087] Data reception and processing: Through the wireless communication module (such as LoRa communication protocol), the three-dimensional coordinate data of the hook collected by the mobile station is transmitted in real time to the data processing center or designated computing device.

[0088] 2. Kalman filter algorithm processes data

[0089] Algorithm application: The Kalman filter algorithm is used to process the three-dimensional coordinate data of the hook continuously collected by the RTK positioning system. Kalman filtering is a recursive algorithm that uses a series of noisy measurement data to estimate the state of a dynamic system.

[0090] Processing process:

[0091] Prediction phase: Based on the state estimate of the previous time step and process noise, the state of the current time step is predicted.

[0092] Update phase: Using the measurements and measurement noise at the current time step, the state estimate and the estimated error covariance are updated.

[0093] Iteration: Repeat the above prediction and update steps until all collected data has been processed.

[0094] It can be understood that the above-mentioned Kalman filter algorithm for processing data is a conventional data processing method embedded in the RTK positioning system, so the principles and formulas of the specific processing process will not be described in detail here.

[0095] 3. Extract displacement components and generate dynamic compensation

[0096] Extract displacement component: Extract the displacement component perpendicular to the ground from the three-dimensional coordinate data of the hook after the Kalman filter algorithm processing. This displacement component reflects the actual movement distance of the hook in the vertical direction.

[0097] Combining initial compensation parameters: combining the extracted displacement components with initial compensation parameters (calculated in step S103). The initial compensation parameters represent the deviation between the height measured by the RTK positioning system and the height measured by the encoder when the tower crane is in an unloaded state.

[0098] Generate dynamic compensation: Calculate the dynamic compensation according to the displacement component and the initial compensation parameters. This dynamic compensation is used to compensate for dynamic errors such as elastic deformation of the boom caused by the load.

[0099] Calculation method: Dynamic compensation amount = displacement component - initial compensation parameter (if the initial compensation parameter is positive, it means that the height measured by RTK is too high; if it is negative, it means that it is too low). However, it should be noted that the "-" sign here does not represent a simple mathematical subtraction, but means that the direction and size of the initial compensation parameter should be considered in the compensation process. In actual applications, it may be necessary to adjust the dynamic compensation amount according to the specific situation to ensure the accuracy and effectiveness of the compensation.

[0100] 4. Output and Application

[0101] The generated dynamic compensation is added to the second height data measured by the encoder of the tower crane hoisting mechanism to obtain the compensated hook height measurement value. This compensated height value is more accurate and can reflect the actual height position of the hook under load.

[0102] Through the above steps, we successfully generated the dynamic compensation under the tower crane load state and applied it to the hook height measurement, thereby improving the accuracy and reliability of the measurement.

[0103] S105: superimposing the dynamic compensation amount onto the second height data, and outputting a compensated hook height measurement value.

[0104] Specifically, superimposing the dynamic compensation amount onto the second height data and outputting the compensated hook height measurement value comprises: inputting the dynamic compensation amount and the second height data into a data processing module, and outputting the compensated hook height measurement value through a preset weight distribution algorithm in the data processing module.

[0105] In step S105, our task is to superimpose the dynamic compensation amount on the second height data measured by the tower crane hoisting mechanism encoder to output the compensated hook height measurement value. The following are the specific implementation details of this step:

[0106] 1. Data Preparation

[0107] Get dynamic compensation: From step S104, we have obtained the dynamic compensation generated based on the RTK positioning system and the initial compensation parameters. This compensation reflects the actual displacement change of the hook under load and takes into account factors such as the elastic deformation of the boom.

[0108] Obtaining the second height data: The encoder of the tower crane hoisting mechanism measures the retracted and extended length of the wire rope in real time to obtain the second height data of the hook. This data is the relative height of the hook relative to the bottom of the tower crane.

[0109] 2. Data Input and Processing

[0110] Data input: The dynamic compensation amount and the second height data are simultaneously input into the data processing module. The data processing module is a specially designed software or hardware component for processing and analyzing the input data.

[0111] Application of preset weight allocation algorithm: In the data processing module, a preset weight allocation algorithm is used to process the dynamic compensation and the second height data. The purpose of this algorithm is to reasonably allocate weights according to the reliability and importance of the two to obtain the most accurate hook height measurement value.

[0112] Algorithm logic: The preset weight allocation algorithm first analyzes the stability and accuracy of the dynamic compensation and second height data. Then, based on these analysis results, a weight value is assigned to both. The size of the weight value reflects the contribution of the data to the final measurement result. Finally, the algorithm adds the weighted dynamic compensation and second height data to obtain the compensated hook height measurement value.

[0113] The core idea of ​​the preset weight allocation algorithm is to assign a suitable weight value to the dynamic compensation amount and the second height data according to their stability and accuracy. This weight value reflects the relative importance of the data in the final measurement result.

[0114] Data stability analysis:

[0115] For the dynamic compensation, it reflects the actual displacement change of the hook under load, and takes into account factors such as the elastic deformation of the boom. Therefore, if the change of the dynamic compensation is stable and conforms to the laws of physics, it can be considered to have high reliability.

[0116] As for the second height data, it comes from the encoder of the tower crane hoisting mechanism, which measures the retracted and released length of the wire rope in real time. If the measurement accuracy of the encoder is stable and not subject to external interference, the second height data will also have high reliability.

[0117] Weight distribution:

[0118] Based on the results of the data stability analysis, a weight value is assigned to the dynamic compensation amount and the second height data. This weight value is a number between 0 and 1 that indicates the contribution of the data to the final measurement result.

[0119] The weight value distribution can be adjusted according to the actual situation. For example, if the stability of the dynamic compensation amount is better than the second height data, a larger weight value can be allocated to it.

[0120] Weighted sum:

[0121] The dynamic compensation amount and the second height data are multiplied by their weight values ​​respectively, and then weighted summed up to obtain the compensated hook height measurement value.

[0122] Specific formula description:

[0123] Although the specific implementation of the preset weight allocation algorithm may vary from system to system, its basic principle can be summarized by the following formula:

[0124] H_after compensation=w1*H_dynamic compensation+w2*H_second height

[0125] in:

[0126] H_After compensation indicates the measured value of the hook height after compensation.

[0127] w1 represents the weight value of the dynamic compensation amount.

[0128] H_Motion Compensation indicates the amount of motion compensation.

[0129] w2 represents the weight value of the second height data.

[0130] H_secondheight represents the second height data.

[0131] It should be noted that:

[0132] The value range of w1 and w2 is 0 to 1, and w1 + w2 = 1. This ensures that the result of the weighted summation is still a reasonable height value.

[0133] The specific values ​​of the weights w1 and w2 can be adjusted according to the actual situation of the system to obtain the most accurate measurement results.

[0134] Optionally, the weight allocation step includes:

[0135] 1. Calculate variance

[0136] Dynamic compensation (H_dynamic compensation): Take the 50 data points in the most recent 5 seconds and calculate the variance σ12;

[0137] Second height data (H_second height): take 30 data points in the last 3 seconds and calculate the variance σ22;

[0138] 2. Assign weights

[0139] If σ12≤0.1 and σ22≤0.05:

[0140] w1=(1 / σ12) / (1 / σ12+1 / σ22), w2=1-w1

[0141] If σ12>0.1: w1=0, w2=1

[0142] If σ22>0.05: w2=0, w1=1

[0143] In summary, the preset weight distribution algorithm analyzes the stability and accuracy of the dynamic compensation amount and the second height data, assigns appropriate weight values ​​to them, and obtains the compensated hook height measurement value through weighted summation. This process helps to improve the accuracy and reliability of the measurement.

[0144] 3. Output the measured value of hook height after compensation

[0145] Result output: After being processed by the preset weight distribution algorithm, the data processing module will output the compensated hook height measurement value. This value takes into account the combined influence of the dynamic compensation amount and the second height data, so it is more accurate and reliable.

[0146] Application of results: The compensated hook height measurement value can be used in many aspects such as safety monitoring and operation guidance of tower cranes. It provides the actual height information of the hook under load, which helps to ensure the safety and accuracy of high-altitude operations.

[0147] Through the above steps, we successfully superimposed the dynamic compensation on the second height data and output the compensated hook height measurement value. This process fully utilizes the high precision of the RTK positioning system and the real-time performance of the dynamic compensation, effectively improving the accuracy and reliability of the hook height measurement.

[0148] Figure 2 A connection diagram of a tower crane lifting height compensation device based on an RTK positioning system provided in this application; Figure 2 As shown, the present application provides a tower crane lifting height compensation device based on an RTK positioning system, the device comprising:

[0149] A positioning system deployment unit, the positioning system deployment unit is used to install a reference station at a ground reference point and a mobile station at a hook connection plate, the reference station and the mobile station are connected via a wireless communication module to form an RTK positioning system;

[0150] A dual-source data acquisition unit, the dual-source data acquisition unit is connected to the positioning system deployment unit, and the dual-source data acquisition unit is used to obtain first height data of the hook through the RTK positioning system, and obtain second height data of the length of the wire rope retracted and released through an encoder of the tower crane hoisting mechanism;

[0151] An empty reference calibration unit, the empty reference calibration unit is connected to the dual-source data acquisition unit, and the empty reference calibration unit is used to calculate an initial compensation parameter based on a deviation value between the first height data and the second height data when the tower crane is in an empty state;

[0152] A dynamic deformation compensation unit, the dynamic deformation compensation unit is connected to the no-load reference calibration unit, and the dynamic deformation compensation unit is used to generate a dynamic compensation amount according to the hook displacement change measured in real time by the RTK positioning system and the initial compensation parameter under the load state of the tower crane;

[0153] A fusion data output unit is connected to the dynamic deformation compensation unit, and is used to superimpose the dynamic compensation amount on the second height data to output a compensated hook height measurement value.

[0154] Specifically, the positioning system deployment unit includes:

[0155] A reference station installation module, the reference station installation module is used to install the reference station at the ground reference point set at 20-50 meters away from the center point of the tower crane tower;

[0156] A mobile station installation module, the mobile station installation module is connected to the base station installation module, and the mobile station installation module is used to fix the mobile station to the hook connection plate through a magnetic fixer.

[0157] Specifically, the no-load reference calibration unit comprises:

[0158] An unloaded data acquisition module, wherein the unloaded data acquisition module is used to synchronously record the first height data and the second height data when the tower crane is unloaded and the boom is at a horizontal reference position;

[0159] An initial compensation parameter acquisition module, wherein the initial compensation parameter acquisition module is connected to the no-load data acquisition module, and the initial compensation parameter acquisition module is used to calculate a deviation value between the first height data and the second height data as the initial compensation parameter.

[0160] Specifically, the dynamic deformation compensation unit includes:

[0161] A three-dimensional coordinate data acquisition module, which is used to process the three-dimensional coordinate data of the hook continuously collected by the RTK positioning system through a Kalman filter algorithm;

[0162] A dynamic compensation acquisition module is connected to the three-dimensional coordinate data acquisition module, and is used to extract the displacement component perpendicular to the ground according to the three-dimensional coordinate data of the hook, and generate the dynamic compensation amount in combination with the initial compensation parameters.

[0163] The present invention provides a tower crane lifting height compensation device based on an RTK positioning system, and its specific implementation is as follows:

[0164] First, the positioning system deployment unit is responsible for installing and configuring the RTK positioning system. This unit includes two main modules:

[0165] Base station installation module: This module is responsible for installing the base station on a ground reference point 20 to 50 meters away from the center of the tower crane. The base station receives satellite signals through its built-in GNSS receiver and serves as a reference point for the RTK positioning system.

[0166] Mobile station installation module: This module is responsible for firmly mounting the mobile station on the hook connection plate through a magnetic fixture. The mobile station is also equipped with a GNSS receiver for receiving satellite signals and wirelessly communicating with the base station to achieve real-time differential positioning.

[0167] Next, the dual-source data acquisition unit is responsible for collecting data from the RTK positioning system and the encoder of the tower crane hoisting mechanism. The unit simultaneously obtains the following two types of data:

[0168] First height data: the height component of the hook's three-dimensional coordinates measured by the RTK positioning system.

[0169] The second height data: the length of the wire rope retracted and released measured by the encoder of the tower crane's hoisting mechanism. This length reflects the change in the vertical distance of the hook relative to a fixed point of the tower crane.

[0170] In order to calibrate the system, the no-load reference calibration unit works with the crane in an unloaded state. The unit includes:

[0171] No-load data acquisition module: When the tower crane is no-load and the boom is in a horizontal reference position, this module synchronously records the first height data provided by the RTK positioning system and the second height data provided by the encoder.

[0172] Initial compensation parameter acquisition module: This module calculates the deviation between the first height data and the second height data, and stores the deviation as the initial compensation parameter. This step is to eliminate the initial height deviation caused by system installation errors, equipment accuracy and other factors.

[0173] When the tower crane is loaded, the dynamic deformation compensation unit starts to work. The unit includes:

[0174] 3D coordinate data acquisition module: This module uses the Kalman filter algorithm to process the 3D coordinate data of the hook continuously collected by the RTK positioning system. The Kalman filter algorithm can smooth the noise in the data and improve the positioning accuracy, thereby more accurately reflecting the actual displacement changes of the hook.

[0175] Dynamic compensation acquisition module: This module extracts the displacement component perpendicular to the ground from the three-dimensional coordinate data processed by Kalman filtering. Then, combined with the previously stored initial compensation parameters, the dynamic compensation is calculated. The dynamic compensation reflects the impact of structural deformation caused by the tower crane load on the hook height measurement.

[0176] Finally, the fusion data output unit superimposes the dynamic compensation amount on the second height data to output the compensated hook height measurement value. This step ensures that accurate and reliable hook height information can be obtained even when the tower crane is loaded.

[0177] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0178] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A tower crane lifting height compensation method based on RTK positioning system, characterized in that: include: A reference station is installed at a ground reference point, and a mobile station is installed on a hook connection plate. The reference station and the mobile station are connected via a wireless communication module to form an RTK positioning system. The first height data of the hook is obtained by the RTK positioning system, and the second height data of the length of the wire rope is obtained by the encoder of the tower crane hoisting mechanism; When the tower crane is in an unloaded state, calculating an initial compensation parameter based on a deviation value between the first height data and the second height data; Under the load state of the tower crane, a dynamic compensation amount is generated according to the hook displacement change measured in real time by the RTK positioning system and the initial compensation parameter; The dynamic compensation amount is superimposed on the second height data to output a compensated hook height measurement value.

2. The compensation method according to claim 1, characterized in that: The method of installing a reference station at a ground reference point and installing a mobile station at a hook connection plate comprises: Install the reference station at the ground reference point 20-50 meters away from the center of the tower crane; The mobile station is fixed to the hook connecting plate by a magnetic fixer.

3. The compensation method according to claim 1, characterized in that: The step of calculating the initial compensation parameter based on the deviation between the first height data and the second height data when the tower crane is in an unloaded state comprises: When the tower crane is unloaded and the boom is at a horizontal reference position, synchronously recording the first height data and the second height data; A deviation value between the first height data and the second height data is calculated according to the first height data and the second height data as the initial compensation parameter.

4. The compensation method according to claim 1, characterized in that: The method of generating a dynamic compensation amount according to the hook displacement change measured in real time by the RTK positioning system and the initial compensation parameter under the tower crane load state includes: Processing the three-dimensional coordinate data of the hook continuously collected by the RTK positioning system through a Kalman filter algorithm; The displacement component perpendicular to the ground is extracted according to the three-dimensional coordinate data of the hook, and the dynamic compensation amount is generated in combination with the initial compensation parameters.

5. The compensation method according to claim 1, characterized in that: The step of superimposing the dynamic compensation amount onto the second height data and outputting a compensated hook height measurement value comprises: The dynamic compensation amount and the second height data are input into a data processing module, and a compensated hook height measurement value is output through a preset weight distribution algorithm in the data processing module.

6. The compensation method according to claim 1, characterized in that: The wireless communication module adopts the LoRa communication protocol.

7. A tower crane lifting height compensation device based on RTK positioning system, characterized in that: The compensation device is applied to any compensation method of claims 1-6, and the compensation device comprises: A positioning system deployment unit, the positioning system deployment unit is used to install a reference station at a ground reference point and a mobile station at a hook connection plate, the reference station and the mobile station are connected via a wireless communication module to form an RTK positioning system; A dual-source data acquisition unit, the dual-source data acquisition unit is connected to the positioning system deployment unit, and the dual-source data acquisition unit is used to obtain first height data of the hook through the RTK positioning system, and obtain second height data of the length of the wire rope retracted and released through an encoder of the tower crane hoisting mechanism; An empty reference calibration unit, the empty reference calibration unit is connected to the dual-source data acquisition unit, and the empty reference calibration unit is used to calculate an initial compensation parameter based on a deviation value between the first height data and the second height data when the tower crane is in an empty state; A dynamic deformation compensation unit, the dynamic deformation compensation unit is connected to the no-load reference calibration unit, and the dynamic deformation compensation unit is used to generate a dynamic compensation amount according to the hook displacement change measured in real time by the RTK positioning system and the initial compensation parameter under the load state of the tower crane; A fusion data output unit is connected to the dynamic deformation compensation unit, and is used to superimpose the dynamic compensation amount on the second height data to output a compensated hook height measurement value.

8. The compensation device according to claim 7, characterized in that: The positioning system deployment unit includes: A reference station installation module, the reference station installation module is used to install the reference station at the ground reference point set at 20-50 meters away from the center point of the tower crane tower; A mobile station installation module, the mobile station installation module is connected to the base station installation module, and the mobile station installation module is used to fix the mobile station to the hook connection plate through a magnetic fixer.

9. The compensation device according to claim 7, characterized in that: The no-load reference calibration unit comprises: An unloaded data acquisition module, wherein the unloaded data acquisition module is used to synchronously record the first height data and the second height data when the tower crane is unloaded and the boom is at a horizontal reference position; An initial compensation parameter acquisition module, wherein the initial compensation parameter acquisition module is connected to the no-load data acquisition module, and the initial compensation parameter acquisition module is used to calculate a deviation value between the first height data and the second height data as the initial compensation parameter.

10. The compensation device according to claim 7, characterized in that: The dynamic deformation compensation unit comprises: A three-dimensional coordinate data acquisition module, which is used to process the three-dimensional coordinate data of the hook continuously collected by the RTK positioning system through a Kalman filter algorithm; A dynamic compensation acquisition module is connected to the three-dimensional coordinate data acquisition module, and is used to extract the displacement component perpendicular to the ground according to the three-dimensional coordinate data of the hook, and generate the dynamic compensation amount in combination with the initial compensation parameters.

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