A method and system for collecting UAV mapping information

Abstract

The present invention relates to the technical field of unmanned aerial vehicle (UAV) surveying and mapping control, and particularly relates to a method and system for collecting UAV surveying and mapping information. The technical solution of the present invention obtains the task data and flight acceleration of the UAV performing the surveying and mapping task. The flight acceleration characterizes the flight state of the UAV. The heading of the UAV can be monitored and adjusted according to the obtained flight acceleration, so that the UAV is as close as possible to the target path of the surveying and mapping task, reducing the influence of yaw on the surveying and mapping accuracy. At the same time, when the UAV is disturbed by air flow and yaws on the target path, it is determined that the task data obtained in the yaw state is abnormal data; the abnormal data is corrected according to the flight acceleration in the yaw state to obtain the corrected task data; according to the corrected task data and the task data obtained when not in the yaw state, the surveying and mapping information of the surveying and mapping task is obtained, and this technical solution improves the accuracy of the obtained surveying and mapping information.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned aerial vehicle (UAV) surveying and mapping control, and particularly to a method and system for collecting UAV surveying and mapping information. Background Art

[0002] UAV surveying and mapping refers to the process in which a UAV conducts aerial surveys and data collection through various sensor devices carried thereon. The UAV can efficiently and accurately obtain image information and geospatial data of the earth's surface from the air. These data can be used to generate maps, digital models, conduct environmental monitoring, resource management, urban planning, etc., providing more accurate, efficient, and secure spatial data solutions for various industries and application scenarios.

[0003] UAV surveying and mapping has various advantages such as convenience, speed, and low cost. However, the stability of the UAV is easily affected by air flow disturbances, which may cause the UAV to fly unstably or even deviate from its flight path. When the UAV is in an area with weak GPS (Global Positioning System) signals, due to the inability to accurately locate the position of the UAV, under the influence of air flow disturbances, the collected ground position and altitude information will be inaccurate, thereby affecting the accuracy of the topographic map drawing. Summary of the Invention

[0004] In order to solve the technical problem of how to accurately obtain surveying and mapping information under air flow disturbances, the purpose of the present invention is to provide a method and system for collecting UAV surveying and mapping information, which reduces the influence of air flow disturbance factors on the UAV's surveying and mapping tasks and makes the obtained surveying and mapping information more accurate. The specific technical solutions adopted are as follows:

[0005] In a first aspect, an embodiment of the present invention provides a method for collecting UAV surveying and mapping information, the method including:

[0006] Obtain the task data and flight acceleration of the UAV performing the surveying and mapping task, where the task data includes the longitude position, latitude position, and corresponding altitude measurement height of the UAV;

[0007] Monitor and adjust the heading of the UAV according to the obtained flight acceleration so that the UAV is on the target path of the surveying and mapping task;

[0008] When the UAV is affected by air flow disturbances and yaws on the target path, determine the task data obtained in the yawed state as abnormal data;

[0009] Correct the abnormal data according to the flight acceleration in the yawed state to obtain the corrected task data;

[0010] Obtain the surveying and mapping information of the surveying task based on the task data after completion of correction and the task data obtained when not in the yaw state.

[0011] In an optional embodiment, perform heading monitoring and heading adjustment on the UAV according to the obtained flight acceleration, including:

[0012] Judge whether the UAV is in the yaw state according to the monitored flight acceleration and the preset accelerator interval;

[0013] When the UAV is in the yaw state, obtain the correction angle of the UAV and the current flight energy of the current control cycle according to the historical flight energy of the UAV in the previous control cycle and the flight acceleration in the yaw state;

[0014] Perform heading correction on the UAV according to the correction angle and the current flight energy until the UAV flies to the target path.

[0015] In an optional embodiment, obtain the correction angle of the UAV and the current flight energy of the current control cycle according to the historical flight energy of the UAV in the previous control cycle and the flight acceleration in the yaw state, including:

[0016] Perform orthogonal decomposition of the flight acceleration in the yaw state on the positive projection plane of the UAV to obtain the first acceleration of the UAV on the target path and the second acceleration perpendicular to the target path;

[0017] Obtain the energy correction value in the yaw state according to the flight acceleration of the UAV in the straight flight state, the first acceleration and the second acceleration;

[0018] Obtain the current flight energy according to the correction result of the historical flight energy by the energy correction value;

[0019] Obtain the correction angle according to the tangent angle between the first acceleration and the second acceleration.

[0020] In an optional embodiment, correct the abnormal data according to the flight acceleration in the yaw state to obtain the task data after completion of correction, including:

[0021] Determine the flight deviation state of the UAV according to the flight acceleration in the yaw state, where the flight deviation state includes flight lag or flight lead on the target path;

[0022] Correspondingly correct the longitude position and latitude position in the obtained abnormal data according to the flight acceleration in different flight deviation states to obtain the task longitude and task latitude of the UAV on the target path;

[0023] Determine the offset distance and offset angle of the UAV in the direction perpendicular to the ground according to the flight acceleration in the yaw state;

[0024] Correspondingly correct the initial measurement value in the obtained abnormal data according to the offset distance and offset angle to obtain the altitude measurement height of the UAV on the target path;

[0025] Determine the mission longitude, mission latitude, and the corresponding altitude measurement height as the mission data after correction.

[0026] In an alternative embodiment, correspondingly correct the longitude position and latitude position in the obtained abnormal data according to the flight acceleration in different flight offset states to obtain the mission longitude and mission latitude of the UAV on the target path, including:

[0027] When the flight offset state is flight ahead, obtain the ahead offset of the UAV according to the flight acceleration, cycle duration, and flight speed of adjacent monitoring cycles;

[0028] Obtain the first mission longitude and the first mission latitude of the UAV according to the correction results of the longitude position and latitude position in the abnormal data by the ahead offset;

[0029] When the flight offset state is flight lag, obtain the lag offset of the UAV according to the flight acceleration, cycle duration, and flight speed of adjacent monitoring cycles;

[0030] Obtain the second mission longitude and the second mission latitude of the UAV according to the correction results of the longitude position and latitude position in the abnormal data by the lag offset.

[0031] In an alternative embodiment, after obtaining the ahead offset or lag offset of the UAV, the method further includes:

[0032] According to the formula Obtain the offset credibility , is the amount of acceleration data obtained in the flight offset state, is the i-th flight acceleration in the flight offset state, is the (i + 1)-th flight acceleration in the flight offset state, is the normalization function;

[0033] Update the ahead offset or lag offset according to the offset credibility to obtain the actual offset in the flight offset state.

[0034] In an alternative embodiment, determine the offset distance and offset angle of the UAV in the direction perpendicular to the ground according to the flight acceleration in the yaw state, including:

[0035] Obtain the path offset of the UAV according to the flight acceleration of the UAV on the target path in the yaw state;

[0036] Obtain the vertical offset of the drone according to the flight acceleration of the drone in the vertical direction under the yaw state;

[0037] Obtain the offset distance of the drone according to the path offset and the vertical offset;

[0038] Obtain the offset angle of the drone according to the sine angle of the vertical offset and the path offset.

[0039] In an alternative embodiment, obtaining the offset distance of the drone according to the path offset and the vertical offset includes:

[0040] According to the formula , obtain the offset distance , where is the path offset, is the vertical offset, is the first credibility of the path offset, is the second credibility of the vertical offset.

[0041] In an alternative embodiment, correspondingly correct the initial measurement value in the obtained abnormal data according to the offset distance and the offset angle to obtain the altitude measurement height of the drone on the target path, including:

[0042] Obtain the first vertical offset of the laser emission and the second vertical offset of the laser reception when the drone performs ground ranging according to the offset distance and the offset angle;

[0043] Obtain the altitude measurement height according to the initial measurement value, the first vertical offset and the second vertical offset.

[0044] In a second aspect, an embodiment of the present invention further provides a drone mapping information acquisition system, the system includes:

[0045] A data acquisition terminal, configured to obtain the task data and flight acceleration of the drone when performing the mapping task, where the task data includes the longitude position, latitude position and corresponding altitude measurement height of the drone;

[0046] A control terminal, connected to the data acquisition terminal, the control terminal is configured to perform heading monitoring and heading adjustment on the drone according to the obtained flight acceleration, so that the drone is on the target path of the mapping task;

[0047] A data processing terminal, connected to the data acquisition terminal, the data processing terminal is configured to determine that the task data obtained under the yaw state is abnormal data when the drone is disturbed by air flow and yaws on the target path;

[0048] The data processing terminal is further configured to correct the abnormal data according to the flight acceleration under the yaw state to obtain the corrected task data;

[0049] The data processing terminal is also used to obtain the surveying and mapping information of the surveying and mapping task according to the task data with corrections completed and the task data obtained when not in the yaw state.

[0050] The present invention has the following beneficial effects:

[0051] The technical solution of the present invention obtains the task data and flight acceleration of the unmanned aerial vehicle (UAV) performing the surveying and mapping task. The flight acceleration characterizes the flight state of the UAV. The heading of the UAV can be monitored and adjusted according to the obtained flight acceleration, so that the UAV is as close as possible to the target path of the surveying and mapping task, reducing the impact of yaw on the surveying and mapping accuracy. At the same time, when the UAV is disturbed by air currents and yaws on the target path, the task data obtained in the yaw state is determined as abnormal data. The abnormal data is corrected according to the flight acceleration in the yaw state to obtain the task data with corrections completed. The surveying and mapping information of the surveying and mapping task is obtained according to the task data with corrections completed and the task data obtained when not in the yaw state. Since the abnormal data is corrected, the impact of air current disturbance on the surveying and mapping accuracy is further reduced, enabling the UAV to comprehensively collect data in the area where the surveying and mapping task is located, making the obtained surveying and mapping information accurate and reliable, and thus improving the accuracy of the surveying and mapping information. Description of the Drawings

[0052] To more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0053] Figure 1 It is a flowchart of a method for collecting UAV surveying and mapping information provided by an embodiment of the present invention;

[0054] Figure 2 It is the first schematic diagram of the UAV implementing heading adjustment provided by an embodiment of the present invention;

[0055] Figure 3 It is the second schematic diagram of the UAV implementing heading adjustment provided by an embodiment of the present invention;

[0056] Figure 4 It is the schematic diagram of the flight offset state being flight lag provided by an embodiment of the present invention;

[0057] Figure 5 It is the schematic diagram of the flight offset state being flight lead provided by an embodiment of the present invention;

[0058] Figure 6 Schematic diagram of initial measurement value correction provided by an embodiment of the present invention;

[0059] Figure 7 Structural schematic diagram of a UAV mapping information acquisition system provided by an embodiment of the present invention. Detailed implementation manners

[0060] In order to further elaborate on the technical means and effects adopted by the present invention to achieve the intended invention purpose, the following describes in detail a UAV mapping information acquisition method and system according to the present invention, its specific implementation manners, structures, features and effects in conjunction with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0061] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs.

[0062] The following specifically describes the specific solutions of a UAV mapping information acquisition method and system provided by the present invention in conjunction with the accompanying drawings.

[0063] Please refer to Figure 1 , which shows a flowchart of a UAV mapping information acquisition method provided by an embodiment of the present invention. The method specifically includes:

[0064] S11. Obtain the task data and flight acceleration of the UAV performing the mapping task. Among them, the task data includes the longitude position, latitude position and corresponding altitude measurement height of the UAV.

[0065] Specifically, the mapping task refers to a task of obtaining geographical data through a UAV for creating a map or performing geographical information analysis. Performing the mapping task can be used as a reference in fields such as land planning, environmental monitoring or urban construction. The data collected by the UAV in the mapping task includes the longitude position, latitude position and altitude measurement height. These data help to determine the geographical location and altitude of the UAV during flight. The longitude position and latitude position can represent the geographical location of the UAV on the earth's surface, while the altitude measurement height represents the vertical distance of the UAV relative to the sea level.

[0066] The task data can be obtained through the built-in Global Positioning System (GPS) and altimeter of the drone. The GPS module provides accurate longitude and latitude positions, while the altimeter measures the altitude of the drone to obtain the altitude measurement. This information is transmitted in real-time to the ground control center through the drone's data transmission system. The flight acceleration is obtained through the accelerometer (or acceleration sensor) on the drone. The accelerometer can monitor the acceleration changes of the drone along each axis in real-time during flight, which is crucial for analyzing the flight stability of the drone and performing precise tasks. The acceleration data helps monitor the motion state of the drone, ensuring the accuracy of its flight path and the successful execution of the mapping task.

[0067] It can be understood that when using drone mapping technology to draw a topographic map, it is mainly drawn based on the altitude measurement of each ground position. Therefore, a lidar sensor can also be installed on the drone to obtain the altitude measurement by emitting laser light to the ground and receiving the laser signal reflected from the ground, and obtain the flight direction data of the drone based on the gyroscope on the drone. Since it is necessary to analyze situations such as the drone encountering strong winds based on the acceleration changes during the drone's navigation, an accelerometer also needs to be installed on the drone to monitor the acceleration of the drone in the horizontal and vertical directions respectively. The monitoring frequency of the acceleration sensor is 100 Hz. According to the time required for a single emission and reception of the laser, the ground height data is collected every 10 s to obtain the altitude measurement.

[0068] S12. Monitor and adjust the heading of the drone according to the obtained flight acceleration so that the drone is on the target path of the mapping task.

[0069] Specifically, when the drone is performing a mapping task, the flight acceleration data is crucial for heading monitoring and adjustment. The flight acceleration is measured in real-time through the accelerometer on the drone. These data provide the acceleration of the drone in the front-back, left-right, and up-down directions. Through this acceleration data, the instantaneous speed and motion direction of the drone can be calculated, and then the deviation degree of its actual heading from the target path can be deduced.

[0070] Heading monitoring involves converting flight acceleration into the speed information of the UAV, and combining its current position and the predetermined path of the mapping task to calculate the heading angle of the UAV. If it is found that the actual heading of the UAV deviates from the target path, the control system of the UAV will detect this deviation and make corresponding heading adjustments. The adjustment process includes changing the flight attitude or direction of the UAV, such as by adjusting the rotation speed or direction of the blades, to correct the heading deviation. This adjustment helps the UAV correct its flight trajectory to ensure that it flies along the target path. To maintain the accuracy of the heading, the UAV needs to perform continuous dynamic corrections. The flight control system will monitor the acceleration data in real time and continuously adjust the heading according to the actual flight state. This dynamic adjustment mechanism enables the UAV to continuously correct its heading during flight to ensure the precise execution of the mapping task.

[0071] Exemplarily, step S12 includes sub-steps S12-1 to S12-3, which are specifically described as follows:

[0072] S12-1. Determine whether the UAV is in a yaw state based on the monitored flight acceleration and the preset accelerator range. The accelerator range can be set based on the mapping accuracy of the mapping task or based on the adjustment requirements of the UAV's actual flight attitude. When the flight acceleration is within the accelerator range, it indicates that the UAV is flying normally, determine that the UAV is not yawing, and control the UAV to continue to perform the mapping task; conversely, when the flight acceleration is not within the accelerator range, it indicates that the UAV is greatly affected by airflow disturbance, and determine that the UAV is in a yaw state.

[0073] When the UAV is performing the mapping task normally, its flight acceleration will be maintained within a small range to ensure the accuracy of the ground data collected by the lidar sensor. When the UAV encounters airflow disturbance under strong wind, the flight acceleration of the UAV will increase or decrease in the short term, making the flight acceleration of the UAV quite different from that in the normal situation. Therefore, a box plot can be used to determine the normal range of the acceleration of the UAV in the horizontal and vertical directions during the process of collecting ground data and , when the acceleration of the UAV exceeds this range, it is considered that the UAV is affected by airflow disturbance at this time, and it is determined that the UAV is in a yaw state.

[0074] S12-2. When the UAV is in a yaw state, based on the historical flight energy of the UAV in the previous control cycle and the flight acceleration in the yaw state, obtain the correction angle of the UAV and the current flight energy in the current control cycle. The correction angle is the adjustment angle for the UAV to fly from the yaw state to the straight-ahead state, and the straight-ahead state is the state where the UAV is normally mapping on the target path of the mapping task. A calculation model can be set based on data processing requirements, input the historical flight energy and flight acceleration into the calculation model, and obtain the correction angle and the current flight energy based on the output result of the calculation model.

[0075] In practical applications, implementing training and verification based on the calculation model will consume a lot of time and energy. Based on this, in a specific implementation manner, sub-step S12-2 includes:

[0076] First step, orthogonally decompose the flight acceleration in the yaw state on the positive projection plane of the UAV (i.e., the ground horizontal direction) to obtain the first acceleration of the UAV on the target path and the second acceleration perpendicular to the target path. Please refer to Figure 2 and Figure 3 , in the figure, D1 is the direction of the UAV in the straight-ahead state, D2 is the direction of the airflow disturbance, and D3 is the direction for the UAV to perform heading correction. It can be seen that to maintain the direction of the straight-ahead state, the magnitude of the adjusted flight power in the direction of the straight-ahead state should be the difference between the original flight power and the wind force of the airflow disturbance in the original flight direction. If the wind is against the flight direction of the UAV, the wind force is negative. In the direction perpendicular to the original flight direction, the adjusted flight power should just be able to offset the magnitude of the wind force of the airflow disturbance in this direction (here, the right side of the original flight direction is defined as the positive direction of the vertical direction).

[0077] The magnitude of the UAV's power can be represented by the acceleration in the straight-ahead state. Since the UAV needs to maintain a uniform flight in the straight-ahead state, the average acceleration in the straight-ahead state is 0, that is, . Decompose the acceleration in the yaw state into the acceleration along the original flight direction; the acceleration perpendicular to the original flight direction. Then the magnitudes of the wind forces of the airflow disturbance in these two directions can be expressed as:

[0078]

[0079]

[0080] Among them, represents the change in the acceleration of the UAV caused by the airflow disturbance in the original flight direction, Represents the change in the acceleration of the UAV caused by the airflow disturbance in the direction perpendicular to the original flight direction, Represents the value of the abnormal acceleration in the original flight direction, Represents the value of the abnormal acceleration in the direction perpendicular to the original flight direction, Represents the acceleration of the UAV in the normal state, that is, Is the flight acceleration in the positive flight state.

[0081] Then, the acceleration of the UAV itself in the two directions should be adjusted to:

[0082]

[0083]

[0084] Among them, Represents the flight acceleration of the UAV itself in the original flight direction after adjustment, Represents the flight acceleration of the UAV itself in the direction perpendicular to the original flight direction after adjustment, that is, the second acceleration.

[0085] In the second step, according to the flight acceleration, the first acceleration and the second acceleration of the UAV in the positive flight state, obtain the energy correction value for the yaw state. The energy correction value can be determined based on a preset correspondence table, or it can be determined based on a calculation model. For example, through the formula

[0086]

[0087] Obtain the energy correction value k, Is the flight acceleration in the positive flight state, Is , Is ; In the formula Represents the total acceleration of the UAV itself after adjustment.

[0088] In the third step, according to the correction result of the historical flight energy by the energy correction value, obtain the current flight energy. The current flight energy can be obtained based on the product of the energy correction value and the historical flight energy, that is , among which, Is the current flight energy, k is the energy correction value, 0 is the historical flight energy.

[0089] In the fourth step, according to the tangent angle between the first acceleration and the second acceleration, obtain the deviation correction angle. Let the deviation correction angle be denoted as , then the flight direction of the UAV after adjustment can be obtained: , Characterizes the angle between the adjusted flight direction and the original flight direction.

[0090] S12 - 3. Correct the heading of the UAV according to the deviation angle and the current flight energy until the UAV flies to the target path. The deviation angle is the angular difference between the actual heading of the UAV and the target path. The UAV calculates the required adjustment amount based on this angle; the current flight energy can be used to determine the battery power on the UAV and the output power of the motor. According to the deviation angle, the controller of the UAV will issue an adjustment instruction to correct the heading by changing the flight attitude and power output. Through continuous monitoring and adjustment, the UAV will finally fly accurately to the target path.

[0091] Based on the above method, the heading of the UAV can be corrected as much as possible to keep it on the target path. However, due to the uncertainty of airflow disturbance during the flight of the UAV, a strong airflow disturbance will still cause the UAV to yaw. When the UAV yaws, enter step S13.

[0092] S13. When the UAV is disturbed by airflow and yaws on the target path, determine that the task data obtained in the yaw state is abnormal data.

[0093] Specifically, the yaw state is the state where the actual flight direction of the UAV deviates from the target path. In the yaw state, the sensor data of the UAV may be affected abnormally. For example, the measured values of longitude, latitude, and altitude may show inaccurate fluctuations. The abnormal performance of these data is usually due to the flight instability caused by airflow disturbance, resulting in the sensor being unable to accurately capture the true position and height of the UAV. In this case, the obtained task data is regarded as abnormal data. This is because these data cannot accurately reflect the true state of the UAV, thus affecting the accuracy of the mapping results. To address this issue, these abnormal data usually need to be processed through data correction or filtering techniques. For example, by combining historical data and the expected flight trajectory, algorithms can be used to filter out the data fluctuations caused by airflow disturbance, thereby improving the reliability of the data.

[0094] S14. Correct the abnormal data according to the flight acceleration in the yaw state to obtain the task data with corrections completed.

[0095] Specifically, under normal circumstances, the UAV should keep the flight acceleration within a small range during the process of collecting altitude measurement. When the UAV encounters airflow disturbance, the acceleration of the UAV will increase or decrease significantly. Therefore, the impact of the UAV encountering airflow disturbance can be analyzed based on the change of the flight acceleration of the UAV. According to the change of the flight acceleration monitored in real time, analyze the flight deviation during the flight adjustment process of the UAV, and then obtain the true position information of the UAV and correct the collected ground position and height data.

[0096] It can be understood that the process of adjusting the power of the drone requires a certain amount of time. Before the power of the drone reaches equilibrium with the airflow disturbance, the drone will still be affected by the airflow disturbance and deviate from its flight path. Therefore, it is necessary to obtain the real-time position of the drone at each monitoring moment according to the deviation distance relative to the original flight position during the process of the drone adjusting its power. The original flight position is the position of the drone at the previous acceleration monitoring moment. When the GPS signal of the drone was good before this, the position of the drone is obtained according to the GPS positioning information at the previous acceleration monitoring moment; if the drone continues to be in a position with weak or no GPS signal, the position of the drone is calculated according to the change in the flight direction of the drone monitored by the gyroscope and the acceleration and deceleration processes of the drone during flight monitored by the accelerometer. Similarly, the correction coefficient of the abnormal data can be determined based on the flight acceleration in the yaw state, and the abnormal data is corrected by the correction coefficient, and then the task data after correction is obtained.

[0097] Exemplarily, step S14 includes sub-steps S14-1 to S14-5, which are specifically described as follows:

[0098] S14-1. Determine the flight deviation state of the drone according to the flight acceleration in the yaw state, where the flight deviation state includes flight lag or flight lead on the target path. Flight lag means that the actual flight position of the drone lags behind the target position on the target path, and this situation usually occurs when the flight acceleration of the drone is insufficient. Please refer to Figure 4 , when the wind direction is against the flight direction of the drone, then under the influence of the airflow disturbance, the speed of the drone will gradually decrease and may even move backward, so the power of the drone itself should gradually increase in this direction, that is, the drone makes a decelerating motion with a decreasing acceleration in this direction.

[0099] On the other hand, flight lead means that the actual flight position of the drone is ahead of the target path, that is, the drone exceeds the expected target position on the target path. Please refer to Figure 5 , when the wind direction is along the flight direction of the drone, then under the influence of the airflow disturbance, the drone will be blown to a farther position, so the power of the drone itself should gradually decrease in this direction, that is, the drone makes an accelerating motion with a decreasing acceleration in this direction.

[0100] S14-2. Corresponding to the flight acceleration in different flight offset states, correct the longitude position and latitude position in the acquired abnormal data to obtain the mission longitude and mission latitude of the UAV on the target path. In different flight offset states, corresponding corrections need to be implemented on the abnormal data. The mission longitude is the longitude after correcting the longitude position in the abnormal data, and the mission latitude is the latitude after correcting the latitude position in the abnormal data. The flight acceleration can determine the offset of the UAV on the target path, and then implement the corresponding corrections for the longitude position and latitude position. Further, sub-step S14-2 is implemented in the following manner.

[0101] First, when the flight offset state is flight ahead, obtain the ahead offset of the UAV according to the flight acceleration, cycle duration, and flight speed of adjacent monitoring periods. The ahead offset is the ahead distance of the UAV at the current flight position from the target position on the target path. Since the heading correction adjustment will be performed whenever there is an abnormal monitored acceleration, the offset of the UAV within the time interval between two monitored flight accelerations can be calculated to obtain the ahead offset. Within the time interval between two flight acceleration monitors, the offset of the UAV relative to the original position in the target path direction is:

[0102]

[0103] Among them, is the ahead offset, which represents the offset of the UAV relative to the original flight position in the original flight direction; is the flight speed, which represents the flight speed of the UAV before being affected by air flow disturbance; is the cycle duration, which represents the time interval of the UAV's flight acceleration monitoring; represents the flight acceleration along the target path at the previous monitoring moment; represents the flight acceleration along the target path at the next monitoring moment.

[0104] Second, according to the correction results of the longitude position and latitude position in the abnormal data by the ahead offset, obtain the first mission longitude and the first mission latitude of the UAV. The target path is known. After obtaining the ahead offset, the longitude position and latitude position during flight ahead can be corrected based on the ahead offset, and then the first mission longitude and the first mission latitude can be obtained. The first mission longitude and the first mission latitude are the longitude and latitude where the UAV is located at the expected target position.

[0105] Third, when the flight offset state is flight lag, obtain the lag offset of the UAV according to the flight acceleration, cycle duration, and flight speed of adjacent monitoring periods. Similarly, the same as the calculation process when the wind direction is along the flight direction of the UAV, the lag offset can be obtained based on the flight acceleration, cycle duration, and flight speed 。

[0106] Step 4: According to the correction results of the longitude position and latitude position in the abnormal data based on the hysteresis offset, obtain the second mission longitude and the second mission latitude of the UAV. Similarly, the second mission longitude and the second mission latitude are the longitude and latitude where the UAV is located at the expected target position when the UAV is in flight hysteresis.

[0107] In practical applications, since the change range of the flight acceleration reflects the change characteristics of the UAV's stability, although the lead offset and the hysteresis offset can be obtained based on the above method, too large a change range may cause insufficient accuracy in the calculation. Based on this, in a specific implementation manner, after obtaining the lead offset or the hysteresis offset of the UAV, the method further includes:

[0108] According to the formula

[0109] Obtain the offset credibility , is the amount of acceleration data obtained in the flight offset state, and the unit is the number of flight acceleration data; is the i-th flight acceleration in the flight offset state, where i is a natural number, is the (i + 1)-th flight acceleration in the flight offset state, is the normalization function; update the lead offset or the hysteresis offset according to the offset credibility to obtain the actual offset in the flight offset state. It can be understood that when the UAV collects ground data, the more the acceleration of the UAV shows a decreasing trend during the flight of the UAV, it means that the UAV is more stable before collecting the data, that is, the obtained offset data should be more accurate; if the fluctuation degree of the flight acceleration of the UAV is large or shows an increasing trend during this process, it means that the stability of the UAV is poor during this process, and then the credibility of the obtained offset is low. Therefore, according to the acceleration change trend of the UAV, the credibility of the offset can be calculated. The offset credibility characterizes the credibility of the corresponding lead offset or hysteresis offset obtained when the UAV is in the flight offset state of flight lead or flight hysteresis, and can be represented by a percentage. Multiply the offset credibility by the initial lead offset or the initial hysteresis offset to obtain the updated lead offset or hysteresis offset.

[0110] So far, the deviation correction of the UAV in the ground horizontal direction has been completed. However, in the actual flight process, the UAV also has an offset in the vertical direction of the target path. The deviation correction of the UAV perpendicular to the target path will be described below.

[0111] S14-3. Determine the offset distance and offset angle of the UAV in the direction perpendicular to the ground based on the flight acceleration in the yaw state. When the UAV is in the yaw state, the monitored flight acceleration can be orthogonally decomposed in the horizontal and vertical directions of the ground to obtain the flight acceleration in the vertical direction of the ground. Based on the flight acceleration in the vertical direction of the ground, the offset distance and offset angle are obtained. The offset distance is the deviation between the position of the UAV in the vertical direction of the ground and the expected target position on the target path, and the offset angle is the angle between the direction of the offset distance and the vertical direction. The specific implementation of sub-step S14-3 will be elaborated below. Specifically, it includes:

[0112] First, obtain the path offset of the UAV based on the flight acceleration of the UAV on the target path in the yaw state. The path offset is the offset of the UAV on the target path, which can be an advanced offset or a lag offset, and represents the offset of the UAV in the horizontal direction of the ground.

[0113] Second, obtain the vertical offset of the UAV based on the flight acceleration of the UAV in the vertical direction in the yaw state. Since there is no speed and acceleration of the UAV in the vertical direction of the original flight direction under normal circumstances, if the UAV has a displacement in this direction, it is the offset in this direction. The offset of the UAV in this direction can be calculated based on the average acceleration of the UAV during the time interval of monitoring the acceleration:

[0114]

[0115] where, is the vertical offset, representing the offset of the UAV in the vertical direction of the original flight direction during the current acceleration monitoring time interval; represents the flight acceleration of the UAV in the vertical direction of the original flight direction at the next monitoring moment, represents the flight acceleration of the UAV in the vertical direction of the original flight direction at the previous monitoring moment, represents the time interval between adjacent flight acceleration monitoring.

[0116] Third, obtain the offset distance of the UAV based on the path offset and the vertical offset. The offset distance can be calculated based on the Pythagorean theorem. The offset distance is the distance between the target position and the position of the UAV in the direction perpendicular to the ground, which is equivalent to calculating the hypotenuse of the Pythagorean theorem, and the path offset and the vertical offset are the right-angled sides respectively.

[0117] To further improve the accuracy of the offset distance calculation, according to the formula , obtain the offset distance where, is the path offset, is the vertical offset, is the first confidence level of the path offset is the second confidence level of the vertical offset. The first confidence level and the second confidence level can also be determined based on the above calculation method of the offset confidence level, which will not be specifically elaborated here.

[0118] Step 4: Obtain the offset angle of the UAV according to the sine angle of the vertical offset and the path offset. The offset angle is denoted as , , is the vertical offset, is the path offset; the path offset lead offset or lag offset .

[0119] S14-4. Corresponding to the offset distance and the offset angle, correct the initial measurement value in the obtained abnormal data to obtain the altitude measurement height of the UAV on the target path. The initial measurement value can be the altitude of the UAV measured by an altimeter or the measurement result of laser ranging. A calculation model can be constructed to implement the correction of the initial measurement value to obtain an accurate altitude measurement height.

[0120] Under normal circumstances, when the UAV is performing a mapping task, it basically maintains the same height for ground height measurement. If the strong wind has a vertical component, due to the instability of the wind, it will also cause large fluctuations of the UAV, resulting in inaccurate height data measurement. Therefore, it is necessary to correct the ground height data affected by the strong wind according to the influence performance of the strong wind. The basic principle is to first calculate the offset of the UAV in the ground vertical direction after being affected by the strong wind, and then calculate the offset of the UAV in the ground vertical direction at the moment of lidar after being affected by the strong wind and the offset of the UAV in the ground vertical direction at the moment of receiving the lidar , if the UAV moves upward, the offset is positive; if the UAV moves downward, the offset is negative; finally, calculate the accurate altitude measurement height. The specific description is as follows:

[0121] Step 1: According to the offset distance and the offset angle, obtain the first vertical offset of laser emission and the second vertical offset of laser reception when the UAV performs ground ranging. Please refer to Figure 6 , is the flight altitude of the UAV set in the mapping task, and the first vertical offset represents the height deviation of the UAV in the ground vertical direction at the time of laser emission, and the second vertical offset It characterizes the height deviation of the UAV in the vertical direction on the ground during laser reception. Both the first vertical offset and the second vertical offset can be obtained by performing trigonometric function analysis based on the corresponding offset distance and offset angle.

[0122] Based on the initial measurement value, the first vertical offset, and the second vertical offset, the measured altitude is obtained. From the time of emitting the laser signal to the time of receiving the signal, for the path that the laser signal passes through in the middle, the ground height data that should be measured at this position under the normal UAV height is calculated as:

[0123]

[0124]

[0125] Among them, represents the ground height data that should be measured at this position under the normal UAV height, represents the total path that the laser passes through during the measurement, is the first vertical offset, is the second vertical offset, represents the speed of laser propagation, represents the time interval from emitting the laser signal to receiving the reflected laser signal.

[0126] Then, according to the altitude of the originally set UAV flight height, the measured ground altitude is calculated:

[0127]

[0128] Among them, is the altitude measurement height after correction, represents the altitude of the originally set UAV flight, represents the ground height data that should be measured at this position under the normal UAV height. Thus, all the altitude measurement heights of the UAV in the yaw state are accurately obtained.

[0129] So far, the deviation correction of the UAV in the vertical direction on the ground has been completed.

[0130] S14-5. Determine the corrected task data by using the mission longitude, mission latitude, and the corresponding altitude measurement height. In order to perform accurate abnormal data correction in the embodiments of the present invention, data analysis and processing are carried out from two dimensions: the ground horizontal direction and the ground vertical direction. The obtained mission longitude, mission latitude, and the corresponding altitude measurement height have good accuracy.

[0131] S15. Obtain the mapping information of the mapping task according to the corrected task data and the task data obtained when not in the yaw state.

[0132] Specifically, for the mission longitude and mission latitude to complete the correction and the longitude position and latitude position, the longitude positions and latitude positions are matched with the corresponding altitude measurement heights to obtain the surveying and mapping information of the surveying and mapping mission. It can be understood that the surveying and mapping information represents the accurate mission data in the surveying and mapping mission, and the surveying and mapping information can be used to implement land planning, environmental monitoring, or urban construction, etc. For example, a topographic map of the information collection area is drawn using a Digital Elevation Model (DEM).

[0133] Based on the same technical concept as the acquisition method, an embodiment of the present invention also provides a UAV surveying and mapping information acquisition system. Please refer to Figure 7 , Figure 7 which is a schematic structural diagram of the acquisition system. The system includes a data acquisition terminal 701, a control terminal 702, and a data processing terminal 703.

[0134] The data acquisition terminal is used to obtain the mission data and flight acceleration of the UAV performing the surveying and mapping mission. Among them, the mission data includes the longitude position, latitude position, and the corresponding altitude measurement height where the UAV is located;

[0135] The control terminal is connected to the data acquisition terminal. The control terminal is used to monitor and adjust the heading of the UAV according to the obtained flight acceleration so that the UAV is on the target path of the surveying and mapping mission;

[0136] The data processing terminal is connected to the data acquisition terminal. The data processing terminal is used to determine that the mission data obtained under the yaw state is abnormal data when the UAV is disturbed by air flow and causes yaw on the target path;

[0137] The data processing terminal is also used to correct the abnormal data according to the flight acceleration under the yaw state to obtain the mission data after completion of correction;

[0138] The data processing terminal is also used to obtain the surveying and mapping information of the surveying and mapping mission according to the mission data after completion of correction and the mission data obtained when not in the yaw state.

[0139] The technical solution provided in the embodiment of the present invention has at least the following technical effects or advantages:

[0140] By obtaining the task data and flight acceleration of the unmanned aerial vehicle (UAV) performing a mapping task, where the flight acceleration characterizes the flight state of the UAV, the heading of the UAV can be monitored and adjusted based on the obtained flight acceleration, enabling the UAV to be as close as possible to the target path of the mapping task and reducing the impact of yaw on the mapping accuracy. At the same time, when the UAV is disturbed by airflows and yaws from the target path, the task data obtained in the yaw state is determined to be abnormal data; the abnormal data is corrected based on the flight acceleration in the yaw state to obtain the corrected task data; based on the corrected task data and the task data obtained when not in the yaw state, the mapping information of the mapping task is obtained. Since the abnormal data is corrected, the impact of airflow disturbance on the mapping accuracy is further reduced, enabling the UAV to comprehensively collect data in the area where the mapping task is located, making the obtained mapping information accurate and reliable, and thus improving the accuracy of the mapping information.

[0141] It should be noted that the above sequence of embodiments of the present invention is only for description and does not represent the superiority or inferiority of the embodiments. The processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0142] Each embodiment in this specification is described in a progressive manner. The same or similar parts among the embodiments can be referred to each other, and the key point of each embodiment is to illustrate the differences from other embodiments.

Claims

1. A method for collecting unmanned aerial vehicle surveying and mapping information, characterized in that, The method includes: Obtaining task data and flight acceleration of the unmanned aerial vehicle (UAV) performing a mapping task, where the task data includes the longitude position, latitude position, and corresponding altitude measurement height of the UAV; Monitoring and adjusting the heading of the UAV according to the obtained flight acceleration so that the UAV is on the target path of the mapping task; When the UAV is disturbed by air flow and yaws on the target path, determining the task data obtained in the yawed state as abnormal data; Correcting the abnormal data according to the flight acceleration in the yawed state to obtain the corrected task data; Obtaining mapping information of the mapping task according to the corrected task data and the task data obtained when not in the yawed state; The correcting the abnormal data according to the flight acceleration in the yawed state to obtain the corrected task data includes: Determining the flight offset state of the UAV according to the flight acceleration in the yawed state, where the flight offset state includes flight lag or flight lead on the target path; Correspondingly correcting the longitude position and latitude position in the obtained abnormal data according to the flight acceleration in different flight offset states to obtain the task longitude and task latitude of the UAV on the target path; Determining the offset distance and offset angle of the UAV in the direction perpendicular to the ground according to the flight acceleration in the yawed state; Correspondingly correcting the initial measurement value in the obtained abnormal data according to the offset distance and the offset angle to obtain the altitude measurement height of the UAV on the target path; Determining the task longitude, the task latitude, and the corresponding altitude measurement height as the corrected task data; The correspondingly correcting the longitude position and latitude position in the obtained abnormal data according to the flight acceleration in different flight offset states to obtain the task longitude and task latitude of the UAV on the target path includes: When the flight offset state is flight lead, obtaining the lead offset of the UAV according to the flight acceleration, cycle duration, and flight speed in adjacent monitoring periods; Obtaining the first task longitude and first task latitude of the UAV according to the correction results of the longitude position and latitude position in the abnormal data by the lead offset; When the flight offset state is flight lag, obtaining the lag offset of the UAV according to the flight acceleration, cycle duration, and flight speed in adjacent monitoring periods; Obtaining the second task longitude and second task latitude of the UAV according to the correction results of the longitude position and latitude position in the abnormal data by the lag offset; After obtaining the lead offset or the lag offset of the UAV, the method further includes: According to the formula obtain the offset credibility , where is the amount of acceleration data obtained in the flight offset state, is the i-th flight acceleration in the flight offset state, is the normalization function; Updating the lead offset or the lag offset according to the offset credibility to obtain the actual offset of the flight offset state.

2. The method for collecting UAV mapping information according to claim 1, characterized in that, Monitoring and adjusting the heading of the UAV according to the obtained flight acceleration includes: Judging whether the UAV is in a yawed state according to the monitored flight acceleration and a preset accelerator interval; When the UAV is in the yaw state, obtain the correction angle of the UAV and the current flight energy of the current control cycle according to the historical flight energy of the UAV in the previous control cycle and the flight acceleration in the yaw state; Perform heading correction on the UAV according to the correction angle and the current flight energy until the UAV flies to the target path.

3. The method for collecting drone mapping information according to claim 2, wherein The obtaining of the correction angle of the UAV and the current flight energy of the current control cycle according to the historical flight energy of the UAV in the previous control cycle and the flight acceleration in the yaw state includes: Perform orthogonal decomposition of the flight acceleration in the yaw state on the positive projection plane of the UAV to obtain the first acceleration of the UAV on the target path and the second acceleration perpendicular to the target path; Obtain the energy correction value in the yaw state according to the flight acceleration of the UAV in the straight-ahead state, the first acceleration, and the second acceleration; Obtain the current flight energy according to the correction result of the historical flight energy by the energy correction value; Obtain the correction angle according to the tangent angle between the first acceleration and the second acceleration.

4. The method for collecting unmanned aerial vehicle mapping information according to claim 1, wherein The determining of the offset distance and offset angle of the UAV in the direction perpendicular to the ground according to the flight acceleration in the yaw state includes: Obtain the path offset of the UAV according to the flight acceleration of the UAV on the target path in the yaw state; Obtain the vertical offset of the UAV according to the flight acceleration of the UAV in the vertical direction in the yaw state; Obtain the offset distance of the UAV according to the path offset and the vertical offset; Obtain the offset angle of the UAV according to the sine angle between the vertical offset and the path offset.

5. The method for collecting UAV mapping information according to claim 4, wherein, The obtaining of the offset distance of the UAV according to the path offset and the vertical offset includes: According to the formula , the offset distance is obtained, where is the path offset, is the vertical offset, is the first credibility of the path offset, is the second credibility of the vertical offset.

6. The method for collecting drone mapping information according to claim 1, wherein, The corresponding correction of the initial measurement value in the obtained abnormal data according to the offset distance and the offset angle to obtain the altitude measurement height of the UAV on the target path includes: Obtain the first vertical offset of the laser emission and the second vertical offset of the laser reception when the UAV performs ground ranging according to the offset distance and the offset angle; Obtain the altitude measurement height according to the initial measurement value, the first vertical offset, and the second vertical offset.

7. An unmanned aerial vehicle mapping information acquisition system, characterized in that, The system includes: A data acquisition terminal for acquiring the task data and flight acceleration of the UAV performing the mapping task, where the task data includes the longitude position, latitude position, and corresponding altitude measurement height of the UAV; A control terminal connected to the data acquisition terminal, and the control terminal is used to monitor and adjust the heading of the UAV according to the acquired flight acceleration so that the UAV is on the target path of the mapping task; A data processing terminal connected to the data acquisition terminal, and the data processing terminal is used to determine that the task data acquired in the yaw state is abnormal data when the UAV is disturbed by air flow and yaws on the target path; The data processing terminal is further configured to correct the abnormal data according to the flight acceleration in the yaw state to obtain the task data with correction completed; The data processing terminal is further configured to obtain the mapping information of the mapping task according to the task data with correction completed and the task data acquired when not in the yaw state; The correcting the abnormal data according to the flight acceleration in the yaw state to obtain the task data with correction completed includes: Determining the flight deviation state of the UAV according to the flight acceleration in the yaw state, where the flight deviation state includes flight lag or flight lead on the target path; Correspondingly correcting the longitude position and latitude position in the acquired abnormal data according to the flight acceleration in different flight deviation states to obtain the task longitude and task latitude of the UAV on the target path; Determining the offset distance and offset angle of the UAV in the direction perpendicular to the ground according to the flight acceleration in the yaw state; Correspondingly correcting the initial measurement value in the acquired abnormal data according to the offset distance and the offset angle to obtain the altitude measurement height of the UAV on the target path; Determining the task longitude, the task latitude and the corresponding altitude measurement height as the task data with correction completed; The correspondingly correcting the longitude position and latitude position in the acquired abnormal data according to the flight acceleration in different flight deviation states to obtain the task longitude and task latitude of the UAV on the target path includes: When the flight deviation state is flight lead, obtaining the lead offset of the UAV according to the flight acceleration, cycle duration and flight speed in adjacent monitoring periods; Obtaining the first task longitude and the first task latitude of the UAV according to the correction results of the longitude position and latitude position in the abnormal data by the lead offset; When the flight deviation state is flight lag, obtaining the lag offset of the UAV according to the flight acceleration, cycle duration and flight speed in adjacent monitoring periods; Obtaining the second task longitude and the second task latitude of the UAV according to the correction results of the longitude position and latitude position in the abnormal data by the lag offset; After obtaining the lead offset or the lag offset of the UAV, it further includes: According to the formula obtain the offset credibility , is the amount of acceleration data obtained in the flight offset state, is the i-th flight acceleration in the flight offset state, is the (i + 1)-th flight acceleration in the flight offset state, is the normalization function; Updating the lead offset or the lag offset according to the offset credibility to obtain the actual offset of the flight deviation state.

Images