Rapid comparison test method for height measurement precision of multi-beam depth sounding system
By setting up test blocks in the dock and utilizing high-precision measurement and unmanned surface vessel scanning, the problem of unstable test conditions in the accuracy verification of multibeam echo sounding systems was solved, enabling rapid, fair, and reliable accuracy comparison, reducing costs and improving efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-31
- Publication Date
- 2026-04-03
AI Technical Summary
The accuracy verification of existing multibeam echo sounding systems relies on field testing, which is greatly affected by the hydrological environment and makes it difficult to control the testing conditions. This results in a lack of fairness and efficiency in equipment comparison results, and indoor verification methods cannot reflect the actual depth sounding accuracy.
Multiple test blocks at different heights are set up in a closed dock area. The elevation of the test blocks is measured using a high-precision level or GNSS system. Automated scanning is carried out by unmanned surface vessels. Combined with water level control and data processing, the height measurement accuracy of the multibeam echo sounder is calculated.
It enables rapid and fair comparison of the accuracy of multibeam echo sounding systems under stable conditions, reduces the influence of benchmark errors, improves testing efficiency and result reliability, has a wide range of applications, low cost and is reusable.
Smart Images
Figure CN121783202A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of marine surveying and hydrological measurement technology, and in particular to a rapid comparative verification method for the height measurement accuracy of a multibeam bathymetry system. Background Technology
[0002] Multibeam bathymetry (MBS) systems are core equipment for topographic mapping of oceans, rivers, lakes, and other bodies of water. Their elevation accuracy directly determines the reliability of the mapping results, and they are widely used in waterway dredging, marine engineering construction, and underwater topographic surveys. Currently, the accuracy verification of MBS systems mainly relies on field tests in actual waters, such as selecting sea areas or lakes with known topography for comparative measurements. However, this method has several limitations: First, field tests are significantly affected by the hydrological environment (such as water flow, waves, and water turbidity), making it difficult to maintain stable test conditions and resulting in a lack of fairness in comparisons between different devices. Second, obtaining elevation benchmarks for known topography in the field is difficult, requiring significant investment of manpower and resources for preliminary control surveys, which is time-consuming and costly. Third, field tests are limited by factors such as weather and route planning, making it impossible to quickly complete batch comparison verification of multiple devices, resulting in low efficiency.
[0003] In addition, existing indoor testing methods mostly focus on the performance testing of the equipment's own circuits and sensors, without constructing a real water depth environment in conjunction with actual depth measurement scenarios. This leads to discrepancies between the test results and the actual application scenarios, and fails to accurately reflect the actual height measurement accuracy of the equipment. Summary of the Invention
[0004] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a rapid comparative verification method for the height measurement accuracy of a multi-beam echo sounding system, which can simulate the real echo sounding environment, control the consistency of test conditions, and quickly and efficiently complete the accuracy comparison of multiple devices.
[0005] To achieve the above objectives, this invention provides a rapid comparative verification method for the height measurement accuracy of a multibeam echo sounder system, comprising the following steps:
[0006] S1. Test site preparation: Select a test site with a water storage space, make test blocks, and set up a test plane on the side. Fix and install multiple test blocks with different test plane heights in the water storage space. The test plane is set horizontally and there is a spacing L between the test blocks.
[0007] S2. Test block elevation benchmark measurement: Obtain the absolute elevation value H of the test plane of each test block. i , where i represents the test block number;
[0008] S3. Water Filling and Water Level Control at the Test Site: Fill the water storage space at the test site with water to ensure that the test planes of all test blocks are submerged and that the water depth on the test planes meets the required values; after the water level stabilizes, obtain the water level elevation H in the water storage space. w ;
[0009] S4. Installation and Scanning of Multibeam Sounding Systems: Select the multibeam sounding systems to be tested and mount them uniformly on the workboat. Perform uniform calibration on each multibeam sounding system to be tested, ensuring that the calibration parameters remain consistent. Control the workboat's movement, and during the journey, each multibeam sounding system independently scans the test plane of all test blocks. Record the scanning data of each multibeam sounding system, including depth data, workboat attitude data, and sound speed data.
[0010] S5. Depth Measurement Data Processing and Accuracy Calculation: Based on the scanning data, extract the depth value D corresponding to the test plane of each test block. ij Where j represents the number of the multibeam echo sounder system; based on the water level elevation H w and the absolute elevation value H of the test block i Calculate the theoretical water depth D of the test plane for each test block. i理 =H w -H i ; Calculate the difference ΔD between the actual water depth value measured by each multibeam echo sounder and the theoretical water depth value. ij = D ij - D i理 Based on ΔD ij The height measurement accuracy of each multibeam echo sounder system was evaluated.
[0011] Furthermore, in S1, the test site is a dock with no obvious water flow and a water level that can be precisely controlled.
[0012] Furthermore, in S1, the test block is made of reinforced concrete or cast iron.
[0013] Furthermore, in S2, a level instrument with second-order or higher accuracy or a GNSS static measurement system is selected to obtain the absolute elevation value of the test plane of each test block. During the measurement process, no less than 3 elevation control points are set. Using the elevation control points as a reference, the test plane of each test block is measured multiple times independently, and the average value is taken as the final absolute elevation value H of the test plane. i .
[0014] Furthermore, in S3, the water depth range of the test plane of the test block is 3-10m.
[0015] Furthermore, in S3, after the water level stabilizes, a water level gauge is used to monitor the water level elevation in real time for a set period of time to ensure that the water level fluctuation does not exceed the set value. At this time, the water level elevation H is recorded. w .
[0016] Furthermore, in S4, the workboat is an unmanned vessel, and the preset navigation route of the workboat is determined according to the position of each test block in the water storage space. When the workboat automatically navigates according to the preset navigation route, each device to be tested independently scans the test plane of all test blocks.
[0017] Furthermore, in S4, the test planes of all test blocks are scanned multiple times independently.
[0018] Furthermore, in S5, based on ΔD ij Calculate ΔD for the same number j. ij The absolute value, average value, standard deviation, and maximum error value are used as evaluation indicators for the height measurement accuracy of the j-numbered multibeam echo sounding system.
[0019] Furthermore, it also includes: S6, Multi-device accuracy comparison: Summarize and compare the evaluation indicators of the height measurement accuracy of all multibeam echo sounding systems to be tested, and intuitively judge the differences in height measurement accuracy of different multibeam echo sounding systems based on the comparison results, and complete the accuracy test and ranking of multibeam echo sounding systems.
[0020] As described above, the rapid comparative testing method of the present invention has the following beneficial effects:
[0021] 1. Highly controllable testing conditions: The test site can be a fixed and stable location such as a closed dock, avoiding interference from environmental factors such as water flow, waves, and weather in field testing. Test parameters such as ship speed, water depth, and water level can be precisely controlled, ensuring that different brands and models of multibeam echo sounders are compared under exactly the same conditions, thus guaranteeing the fairness and reliability of the test results.
[0022] 2. Precise and Reliable Accuracy Benchmark: The absolute elevation of the test plane of the test block is obtained through high-precision land elevation measurement, with a benchmark error not exceeding ±2mm. This provides an accurate reference standard for calculating depth measurement accuracy and effectively reduces the impact of benchmark error on the test results.
[0023] 3. Significantly improved testing efficiency: Closed sites such as docks can be used as testing grounds, eliminating the need for complex preliminary site exploration and route planning. Unmanned vessels can achieve automated scanning, and the testing time for a single multibeam echo sounder system can be less than 2 hours. Multiple systems can be tested sequentially and continuously, which is more efficient than field testing and can quickly complete the accuracy comparison of a batch of multibeam echo sounder systems.
[0024] 4. Wide range of applications: The height, quantity and dock water level of the test blocks can be adjusted according to the testing requirements, and it is compatible with multibeam echo sounding systems of different working water depths and different accuracy levels. Whether it is a shallow draft equipment or a deep draft equipment, it can achieve accurate testing. At the same time, the design of the regular test blocks makes the extraction and processing of echo sounding data easier and reduces the difficulty of data processing.
[0025] 5. Low cost and reusable: The dock and test blocks can be reused, eliminating the need to rebuild the site for each test; the cost of test block preparation and elevation measurement is far lower than the cost of control measurement of known terrain in the field, significantly reducing the testing cost of multi-device comparison. Attached Figure Description
[0026] Figure 1 This is a flowchart illustrating the rapid comparison and testing method of the present invention. Detailed Implementation
[0027] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.
[0028] It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and objectives of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.
[0029] It should also be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or may be connected to an intermediary component. When a component is referred to as being "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component through an intermediary component.
[0030] Furthermore, the use of terms such as "first" and "second" in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed in this application.
[0031] See Figure 1 This invention provides a rapid comparative verification method for the height measurement accuracy of a multibeam echo sounder system, comprising the following steps:
[0032] S1. Test site preparation:
[0033] Select a test site with a water storage space, make test blocks, and set up a test plane on the side. Fix multiple test blocks with different test plane heights in the water storage space. The test plane is set horizontally and there is a spacing L between the test blocks.
[0034] As a preferred design, a well-sealed dock of suitable size is selected as the test site. The dock has no significant water flow, and the water level can be precisely controlled. Several regularly shaped test blocks are prepared, made of high-density, high-stability materials such as reinforced concrete or cast iron to prevent displacement or tilting during testing. The heights of the test blocks vary, preferably within the range of 0.5-5m, adjusted according to testing requirements to create a staggered reference surface. All test blocks are evenly laid on the dock's bottom plate, with a minimum spacing L of 2m between blocks. This ensures that the multibeam echo sounder beams completely cover the test plane of each block and avoids interference between adjacent blocks. After laying the test blocks, ensure their bottom surfaces are tightly fitted to the dock's bottom plate, using weights or bolts to prevent movement after water is introduced.
[0035] S2. Measurement of the elevation benchmark of the test block:
[0036] Obtain the absolute elevation value H of the test plane of each test block. i , where i represents the test block number.
[0037] Preferably, in this embodiment, a high-precision land elevation measurement method is employed, using a level instrument of second-order or higher accuracy or a GNSS static measurement system to obtain the absolute elevation value of the test plane of each test block. During the measurement process, at least three elevation control points are set up, which must be located on stable ground around the dock and have no relative settlement with the dock floor. Using the elevation control points as a reference, the test plane of each test block is measured independently multiple times, preferably at least three times, and the average value is taken as the final absolute elevation value H of the test plane. i , i=1,2,...,n, where n is the number of test blocks, and the measurement accuracy error does not exceed ±2mm.
[0038] S3. Watering and Water Level Control at the Test Site:
[0039] Fill the water storage space at the test site with water, ensuring that the test planes of all test blocks are submerged and that the water depth on each test plane meets the required value; after the water level stabilizes, obtain the water level elevation H in the water storage space. w , which serves as the benchmark parameter for subsequent depth sounding data calculation;
[0040] Preferably, in this embodiment, clean water is slowly injected into the dock, avoiding water flow impacting the test blocks during the injection process. The final water level is controlled according to the testing requirements to ensure that all test blocks are submerged, and the water depth from the top surface of the test blocks to the water surface is preferably 3-10m. After the water level stabilizes, a water level gauge is used to monitor the water level elevation H in the dock in real time. w Continuously monitor for a certain period of time (preferably 30 minutes) to ensure that the water level fluctuation does not exceed ±5mm, and then record the water level elevation H at this time. w This serves as the baseline parameter for subsequent depth sounding data calculations.
[0041] S4. Installation and scanning of multibeam echo sounder system:
[0042] Select the multibeam echo sounder systems to be tested and mount them uniformly on the workboat. Perform uniform calibration on each multibeam echo sounder system to be tested, and keep the calibration parameters consistent. Control the workboat to move, and during the journey, each multibeam echo sounder system independently scans the test plane of all test blocks. Record the scan data of each multibeam echo sounder system, including depth data, workboat attitude data and sound speed data.
[0043] Preferably, in this embodiment, the multibeam echo sounder systems to be tested can include equipment of different brands or models. The workboat is an unmanned surface vessel (USV), and the installation position of the USV must meet the installation requirements of the multibeam transducer. The draft of the transducer is fixed (set according to the equipment manual, with an error not exceeding ±1cm), and the installation direction is consistent with the sailing direction of the USV. Then, each multibeam echo sounder system to be tested is uniformly calibrated (including attitude calibration and sound velocity calibration), and the calibration parameters are kept consistent to ensure the fairness of the testing conditions.
[0044] In this embodiment, the navigation parameters of the unmanned surface vessel (USV) are set: the vessel speed is controlled between 1-3 m / s, specifically adjusted according to the optimal operating speed of the multibeam echo sounder system, and the test vessel speed of all devices under test is kept consistent. Based on the position of each test block in the water storage space, a preset navigation route for the working vessel is determined. The navigation route uses a grid pattern to ensure that each device under test performs multiple independent scans of the test plane of all test blocks while the working vessel automatically navigates along the preset route. After the USV is started, it scans according to the preset navigation route. Each multibeam echo sounder system performs multiple independent scans of all test blocks, and the scan data of each multibeam echo sounder system is recorded, including depth data, working vessel attitude data (heading, roll, pitch), and sound speed data. The working vessel attitude data (heading, roll, pitch) of each multibeam echo sounder system is identical.
[0045] S5. Bathymetry data processing and accuracy calculation:
[0046] It is preferable to first preprocess the scanning data of each multibeam echo sounder system, including attitude correction, sound velocity correction, water level correction, etc., which can be done using existing methods, thereby eliminating the influence of the environment and equipment attitude on the echo sounding results.
[0047] Based on the scanning data, extract the depth value D corresponding to the test plane of each test block. ij Where j represents the multibeam echo sounder system number, i.e., the water depth from the water surface to the test plane of the test block measured by the multibeam echo sounder system. Then, based on the water level elevation H... w and the absolute elevation value H of the test block i Calculate the theoretical water depth D of the test plane for each test block. i理 =H w -H i Then, calculate the difference ΔD between the actual water depth value measured by each multibeam echo sounder and the theoretical water depth value. ij =D ij - D i理 ΔD ij Let be the depth measurement error of the multibeam echo sounding system numbered j on the test plane of the test block numbered i.
[0048] Then based on ΔD ij To evaluate the height measurement accuracy of various multibeam echo sounding systems, specifically based on ΔD ij Calculate ΔD for the same number j. ij The absolute value, average value, standard deviation, and maximum error value are used as evaluation indicators for the height measurement accuracy of multibeam echo sounding system j, thus obtaining the evaluation indicators for the height measurement accuracy of each multibeam echo sounding system. Specifically, the absolute value, average value, reflects the systematic error of the multibeam echo sounding system; the standard deviation reflects the measurement stability of the multibeam echo sounding system; and the maximum error value reflects the limiting accuracy of the multibeam echo sounding system.
[0049] S6. Comparison of accuracy across multiple devices:
[0050] The evaluation indicators (absolute value, average value, standard deviation, and maximum error value) of the height measurement accuracy of all multibeam echo sounding systems to be tested are summarized and compared. Based on the comparison results, the differences in height measurement accuracy of different multibeam echo sounding systems can be intuitively judged, and the accuracy test and ranking of multibeam echo sounding systems can be completed.
[0051] S7, Multi-device accuracy comparison:
[0052] In this embodiment, after the inspection is completed, the water in the dock is drained, debris on the surface of the test block is cleaned, and the position and stability of the test block are checked to prepare for subsequent tests.
[0053] As can be seen from the above, the rapid comparative testing method of the present invention has the following beneficial effects:
[0054] 1. Highly controllable testing conditions: The test site can be a fixed and stable location such as a closed dock, avoiding interference from environmental factors such as water flow, waves, and weather in field testing. Test parameters such as ship speed, water depth, and water level can be precisely controlled, ensuring that different brands and models of multibeam echo sounders are compared under exactly the same conditions, thus guaranteeing the fairness and reliability of the test results.
[0055] 2. Precise and Reliable Accuracy Benchmark: The absolute elevation of the test plane of the test block is obtained through high-precision land elevation measurement, with a benchmark error not exceeding ±2mm. This provides an accurate reference standard for calculating depth measurement accuracy and effectively reduces the impact of benchmark error on the test results.
[0056] 3. Significantly improved testing efficiency: Closed sites such as docks can be used as testing grounds, eliminating the need for complex preliminary site exploration and route planning. Unmanned vessels can achieve automated scanning, and the testing time for a single multibeam echo sounder system can be less than 2 hours. Multiple systems can be tested sequentially and continuously, which is more efficient than field testing and can quickly complete the accuracy comparison of a batch of multibeam echo sounder systems.
[0057] 4. Wide range of applications: The height, quantity and dock water level of the test blocks can be adjusted according to the testing requirements, and it is compatible with multibeam echo sounding systems of different working water depths and different accuracy levels. Whether it is a shallow draft equipment or a deep draft equipment, it can achieve accurate testing. At the same time, the design of the regular test blocks makes the extraction and processing of echo sounding data easier and reduces the difficulty of data processing.
[0058] 5. Low cost and reusable: The dock and test blocks can be reused, eliminating the need to rebuild the site for each test; the cost of test block preparation and elevation measurement is far lower than the cost of control measurement of known terrain in the field, significantly reducing the testing cost of multi-device comparison.
[0059] In summary, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.
[0060] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.
Claims
1. A rapid comparative verification method for the height measurement accuracy of a multibeam echo sounder system, characterized in that: Includes the following steps: S1. Test site preparation: Select a test site with a water storage space, make test blocks, and set up a test plane on the side. Fix and install multiple test blocks with different test plane heights in the water storage space. The test plane is set horizontally and there is a spacing L between the test blocks. S2. Test block elevation benchmark measurement: Obtain the absolute elevation value H of the test plane of each test block. i , where i represents the test block number; S3. Water Filling and Water Level Control at the Test Site: Fill the water storage space at the test site with water to ensure that the test planes of all test blocks are submerged and that the water depth on the test planes meets the required values; after the water level stabilizes, obtain the water level elevation H in the water storage space. w ; S4. Installation and Scanning of Multibeam Sounding Systems: Select the multibeam sounding systems to be tested and mount them uniformly on the workboat. Perform uniform calibration on each multibeam sounding system to be tested, ensuring that the calibration parameters remain consistent. Control the workboat's movement, and during the journey, each multibeam sounding system independently scans the test plane of all test blocks. Record the scanning data of each multibeam sounding system, including depth data, workboat attitude data, and sound speed data. S5. Depth Measurement Data Processing and Accuracy Calculation: Based on the scanning data, extract the depth value D corresponding to the test plane of each test block. ij Where j represents the number of the multibeam echo sounder system; based on the water level elevation H w and the absolute elevation value H of the test block i Calculate the theoretical water depth D of the test plane for each test block. i理 =H w -H i ; Calculate the difference ΔD between the actual water depth value measured by each multibeam echo sounder and the theoretical water depth value. ij = D ij - D i理 Based on ΔD ij The height measurement accuracy of each multibeam echo sounder system was evaluated.
2. The rapid comparison and testing method according to claim 1, characterized in that: In S1, the test site is a dock with no obvious water flow and a water level that can be precisely controlled.
3. The rapid comparison test method according to claim 1 or 2, characterized in that: In S1, the test block is made of reinforced concrete or cast iron.
4. The rapid comparison test method according to claim 1, characterized in that: In S2, a level instrument with second-order or higher accuracy or a GNSS static measurement system is selected to obtain the absolute elevation value of the test plane of each test block. During the measurement process, no less than 3 elevation control points are set. Using the elevation control points as a reference, the test plane of each test block is measured multiple times independently, and the average value is taken as the final absolute elevation value H of the test plane. i .
5. The rapid comparison test method according to claim 1, characterized in that: In S3, the water depth range of the test plane of the test block is 3-10m.
6. The rapid comparison test method according to claim 1, characterized in that: In S3, after the water level stabilizes, a water level gauge is used to monitor the water level elevation in real time for a set period of time to ensure that the water level fluctuation does not exceed the set value. At this time, the water level elevation H is recorded. w .
7. The rapid comparison test method according to claim 1, characterized in that: In S4, the workboat is an unmanned vessel, and the preset navigation route of the workboat is determined according to the position of each test block in the water storage space. When the workboat automatically navigates according to the preset navigation route, each device to be tested independently scans the test plane of all test blocks.
8. The rapid comparison test method according to claim 1 or 7, characterized in that: In S4, the test plane of all test blocks is scanned multiple times independently.
9. The rapid comparison test method according to claim 1, characterized in that: In S5, based on ΔD ij Calculate ΔD for the same number j. ij The absolute value, average value, standard deviation, and maximum error value are used as evaluation indicators for the height measurement accuracy of the j-numbered multibeam echo sounding system.
10. The rapid comparison test method according to claim 1, characterized in that: Also includes: S6. Multi-device accuracy comparison: Summarize and compare the evaluation indicators of the height measurement accuracy of all multibeam echo sounding systems to be tested, and intuitively judge the differences in height measurement accuracy of different multibeam echo sounding systems based on the comparison results, and complete the accuracy test and ranking of multibeam echo sounding systems.