Flight device and control method thereof

Abstract

The invention provides a flight device and a control method thereof. The apparatus obtains a plurality of magnetic field data measured over a time interval. The apparatus calculates a plurality of orientation orientations based on the plurality of magnetic field data. The apparatus calculates a plurality of displacement orientations based on a plurality of displacement records corresponding to the time interval. The device compares the plurality of orientations and orientations with the plurality of displacement orientations, and determines whether the flight device is subjected to a magnetic interference in the time interval. In response to determining that the flying device is subject to the magnetic disturbance, the device performs an avoidance operation. According to the flight device and the control method thereof, whether the flight device is subjected to magnetic interference or not is judged by comparing different data, and the flight device is prevented from being out of control due to environmental influence.

Description

Technical Field

[0001] This disclosure relates to a flight device and its control method, and more particularly to a flight device and its control method with the function of avoiding magnetic interference. Background Technology

[0002] Bridges are a crucial part of national or regional transportation infrastructure, and bridge inspection is an essential task for maintaining traffic safety. However, bridge inspection operations are often hampered by factors such as terrain and industrial safety, presenting numerous challenges.

[0003] Some existing technologies use drones to inspect bridges. However, since drones rely on many electronic components to operate, the high-voltage cables and magnetized steel bars on the bridge may cause magnetic interference to the drones, leading to abnormalities in the electronic components. This can result in the drones being unable to locate themselves, deviating from their flight paths, or even crashing.

[0004] Therefore, identifying and avoiding sources of magnetic interference is a goal that the industry urgently needs to work on. Summary of the Invention

[0005] To address the aforementioned problems, this disclosure proposes a control method applicable to a flight device, comprising the steps of: acquiring multiple first magnetic field data measured in a first time interval; calculating multiple first orientation azimuths corresponding to a magnetic pole based on the multiple first magnetic field data; calculating multiple first displacement azimuths based on multiple first displacement records corresponding to the first time interval; comparing the multiple first orientation azimuths and the multiple first displacement azimuths to determine whether the flight device is subjected to a magnetic interference in the first time interval; and controlling the flight device to perform an avoidance operation in response to determining that the flight device is subjected to the magnetic interference.

[0006] In one embodiment of the present invention, the step of calculating the plurality of first displacement orientations further includes: calculating the plurality of first displacement orientations based on a plurality of first acceleration values ​​measured by an accelerometer in the first time interval.

[0007] In one embodiment of the present invention, the step of calculating the plurality of first displacement orientations further includes: calculating the plurality of first displacement orientations based on a plurality of positioning positions measured by a positioning element in the first time interval.

[0008] In one embodiment of the present invention, the step of comparing the plurality of first orientation azimuths and the plurality of first displacement azimuths further includes: calculating a first azimuth difference and a second azimuth difference between the plurality of first orientation azimuths and the plurality of first displacement azimuths corresponding to the first time point and the second time point based on a first time point and a second time point in the first time interval; calculating a first variation between the first azimuth difference and the second azimuth difference; and determining, based on the first variation, whether the flight device is subjected to the magnetic interference in the first time interval.

[0009] In one embodiment of the present invention, the step of comparing the plurality of first orientation azimuths and the plurality of first displacement azimuths further includes: in response to the first variation being greater than a second threshold, calculating a third position difference between the plurality of first orientation azimuths and the plurality of first displacement azimuths at the third time point based on a third time point in the first time interval; calculating a second variation between the third position difference and the first azimuth difference; and in response to the second variation being greater than the second threshold, determining that the flight device is subjected to the magnetic interference in the first time interval.

[0010] In one embodiment of the invention, the method further includes: calculating a magnetic field value range based on positioning information of the flight device; performing a correction operation based on initial magnetic field data and the magnetic field value range, wherein the flight device measures the initial magnetic field data at a time point earlier in the first time interval; and not calculating the plurality of first orientation directions in response to the failure to complete the correction operation.

[0011] In one embodiment of the invention, the method further includes: calculating a magnetic field strength difference between one of the plurality of first magnetic field data and a calibration value, wherein the calibration value is generated based on a positioning information of the flight device; and determining that the flight device is subjected to the magnetic interference in response to the magnetic field strength difference being greater than a first threshold.

[0012] In one embodiment of the present invention, the method further includes: receiving, from the flight device, a plurality of second magnetic field data measured in a second time interval, wherein the second time interval is longer than the first time interval and includes the first time interval; calculating, based on the plurality of second magnetic field data, a plurality of second orientation azimuths corresponding to the magnetic poles; calculating, based on a plurality of second displacement records corresponding to the second time interval, a plurality of second displacement azimuths; and comparing the plurality of second orientation azimuths and the plurality of second displacement azimuths to determine whether the flight device is subjected to the magnetic interference in the second time interval.

[0013] In one embodiment of the present invention, the avoidance operation includes: estimating a range and a location of an interference source based on a plurality of first magnetic field data corresponding to a plurality of locations; and generating an avoidance path based on the range and the location of the interference source to control the flight device to avoid the interference source.

[0014] In one embodiment of the present invention, the step of generating the avoidance path further includes: determining a starting point and an ending point based on an original path; and performing at least one iterative operation to determine at least one path point based on the starting point, the ending point, the range and the location of the interference source, wherein each of the at least one path point is iteratively generated based on the starting point or a previous path point, and the at least one path point connects the starting point and the ending point to form the avoidance path.

[0015] This disclosure also provides a flight device including a magnetometer and a processor. The processor is electrically connected to the magnetometer and is configured to perform the following operations: receiving a plurality of first magnetic field data measured by the magnetometer in a first time interval; calculating a plurality of first orientation azimuths corresponding to a magnetic pole based on the plurality of first magnetic field data; calculating a plurality of first displacement azimuths based on a plurality of first displacement records corresponding to the first time interval; comparing the plurality of first orientation azimuths and the plurality of first displacement azimuths to determine whether the magnetometer is subjected to a magnetic interference in the first time interval; and performing an avoidance operation in response to determining that the magnetometer is subjected to the magnetic interference.

[0016] In one embodiment of the present invention, the operation of calculating the plurality of first displacement orientations further includes: calculating the plurality of first displacement orientations based on a plurality of first acceleration values ​​measured by an accelerometer in the first time interval.

[0017] In one embodiment of the present invention, the operation of calculating the plurality of first displacement orientations further includes: calculating the plurality of first displacement orientations based on a plurality of positioning positions measured by a positioning element in the first time interval.

[0018] In one embodiment of the present invention, the operation of comparing the plurality of first orientation azimuths and the plurality of first displacement azimuths further includes: calculating a first azimuth difference and a second azimuth difference between the plurality of first orientation azimuths and the plurality of first displacement azimuths corresponding to the first time point and the second time point based on a first time point and a second time point in the first time interval; calculating a first variation between the first azimuth difference and the second azimuth difference; and determining whether the magnetometer is subjected to magnetic interference in the first time interval based on the first variation.

[0019] In one embodiment of the present invention, the operation of comparing the plurality of first orientation azimuths and the plurality of first displacement azimuths further includes: in response to the first variation being greater than a second threshold, calculating a third position difference between the plurality of first orientation azimuths and the plurality of first displacement azimuths at the third time point based on a third time point in the first time interval; calculating a second variation between the third position difference and the first azimuth difference; and in response to the second variation being greater than the second threshold, determining that the magnetometer is subjected to magnetic interference in the first time interval.

[0020] In one embodiment of the invention, the processor further performs the following operations: calculating a magnetic field value range based on positioning information of the flight device; performing a correction operation based on initial magnetic field data and the magnetic field value range, wherein the magnetometer measures the initial magnetic field data at a time point earlier in the first time interval; and not calculating the plurality of first orientation directions in response to the incomplete completion of the correction operation.

[0021] In one embodiment of the invention, the processor further performs the following operations: calculating a magnetic field strength difference between one of the plurality of first magnetic field data and a calibration value, wherein the calibration value is generated based on a positioning information of the flight device; and determining that the magnetometer is subjected to magnetic interference in response to the magnetic field strength difference being greater than a first threshold.

[0022] In one embodiment of the invention, the processor further performs the following operations: receiving from the magnetometer a plurality of second magnetic field data measured in a second time interval, wherein the second time interval is longer than the first time interval and includes the first time interval; calculating a plurality of second orientation azimuths corresponding to the magnetic poles based on the plurality of second magnetic field data; calculating a plurality of second displacement azimuths based on a plurality of second displacement records corresponding to the second time interval; and comparing the plurality of second orientation azimuths and the plurality of second displacement azimuths to determine whether the second time interval of the magnetometer is affected by the magnetic interference.

[0023] In one embodiment of the present invention, the avoidance operation includes: estimating a range and a location of an interference source based on a plurality of first magnetic field data corresponding to a plurality of locations; and generating an avoidance path based on the range and the location of the interference source to control the flight device to avoid the interference source.

[0024] In one embodiment of the present invention, the operation of generating the avoidance path further includes: determining a starting point and an ending point based on an original path; and performing at least one iterative operation to determine at least one path point based on the starting point, the ending point, the range and the location of the interference source, wherein each of the at least one path point is iteratively generated based on the starting point or a previous path point, and the at least one path point connects the starting point and the ending point to form the avoidance path.

[0025] It should be understood that the foregoing general description and the following specific description are merely exemplary and explanatory, and are intended to provide further explanation of the claimed disclosure. Attached Figure Description

[0026] To make the above and other objects, features, advantages and embodiments of this disclosure more apparent and understandable, the accompanying drawings are described below:

[0027] Figure 1 This is a schematic diagram of the flight device in the first embodiment of this disclosure;

[0028] Figure 2 This is a schematic diagram illustrating the operation of the flight device in determining magnetic interference in some embodiments of this disclosure;

[0029] Figures 3A to 3D This is a schematic diagram illustrating how a flight device estimates the location and range of an interference source and generates an avoidance path in some embodiments of this disclosure; and

[0030] Figure 4 This is a flowchart of the flight device control method in the second embodiment of this disclosure.

[0031] [Symbol Explanation]

[0032] 1: Flight device

[0033] 12: Processor

[0034] 14: Magnetometer

[0035] OP1, OP2_1, OP2_2, OP3_1, OP3_2, OP3_3, OP3_4, OP4_1, OP4_2, OP4_3, OP4_4, OP5: Operation

[0036] DN: Unmanned Aerial Vehicle

[0037] OR: original path

[0038] x, y, z: axes

[0039] IA: Interference Area

[0040] W: Interference source

[0041] B: Block

[0042] SB: Start Block

[0043] EB: Endpoint Block

[0044] DB: Drone Block

[0045] AR: Avoidance Path

[0046] 200: Flight Device Control Methods

[0047] S201~S205: Steps Detailed Implementation

[0048] To make the description of this disclosure more detailed and complete, reference may be made to the accompanying drawings and the various embodiments described below, in which the same numbers represent the same or similar elements.

[0049] Please refer to Figure 1 This is a schematic diagram of the flight device 1 according to the first embodiment of this disclosure. The flight device 1 includes a processor 12 and a magnetometer 14, wherein the processor 12 is electrically connected to the magnetometer 14. The flight device 1 is used to detect the presence of magnetic interference in the surrounding environment and avoid interference sources while flying. In some embodiments, the flight device 1 is an unmanned aerial vehicle.

[0050] In some embodiments, processor 12 may include a central processing unit (CPU), a graphics processing unit (GPU), a microcontroller unit (MCU), a multiprocessor, a distributed processing system, an application-specific integrated circuit (ASIC), and / or a suitable computing unit.

[0051] The magnetometer 14 is used to measure magnetic field data in the environment, including multiple magnetic field strengths in multiple directions, or a resultant magnetic field vector. Based on this, the flight device 1 can determine its orientation according to the magnetic field data. In some embodiments, the magnetometer 14 is an electronic compass, also used to enable the flight device 1 to determine its orientation. In some embodiments, the magnetometer 14 is an electronic compass integrated into an inertial measurement unit (IMU).

[0052] In order to detect whether there is magnetic interference in the surrounding area, the processor 12 first calculates multiple orientations corresponding to a magnetic pole based on multiple magnetic field data measured by the magnetometer 14 over a period of time. The multiple orientations are based on the magnetic field direction measured by the magnetometer 14, and the orientation of the flight device 1 corresponding to the movement of the Earth's magnetic field is deduced (e.g., due south, northeast).

[0053] It should be noted that, since the flight device 1 may not necessarily fly in a fixed direction (e.g., forward towards the nose) when it is in flight, it may also move laterally or backward. Therefore, the processor 12 calculates the magnetic field azimuth angle measured by the magnetometer 14 when calculating the orientation, and combines it with flight control information such as forward, lateral, and backward movement during flight to determine the orientation of the flight device 1.

[0054] Next, the processor 12 calculates multiple displacement orientations based on multiple displacement records (i.e., movement trajectories) of the flight device 1 within the same time period, wherein the multiple displacement orientations represent multiple velocity directions of the flight device 1 at the multiple time points within that time period.

[0055] Accordingly, the plurality of orientation azimuths and the plurality of displacement azimuths are compared. Under normal circumstances, when the flight direction of the flight device 1 deflects (i.e., the displacement azimuth changes), the orientation azimuth calculated based on the magnetometer 14 will also deflect synchronously. Therefore, the angle between the plurality of displacement azimuths and the plurality of orientation azimuths should remain at a certain value.

[0056] However, if the magnetometer 14 is subjected to magnetic interference at this time, even if the flight device 1 flies in the same direction, the magnetic field data measured by the magnetometer 14 will still be affected by external forces and will continue to change. Therefore, the angle between the multiple displacement orientations and the multiple orientations will not remain constant.

[0057] According to the above embodiments, by comparing the multiple displacement orientations and the multiple orientation orientations, the flight device 1 proposed in this disclosure can determine whether the magnetometer 14 is subject to magnetic interference during that period of time. When it is determined that the magnetometer 14 is subject to magnetic interference, the processor 12 controls the flight device 1 to avoid the interference source, such as hovering, returning along the original path, or bypassing the interference source.

[0058] Specifically, the processor 12 performs the following operations: receiving multiple first magnetic field data measured in a first time interval from the magnetometer; calculating multiple first orientations corresponding to a magnetic pole based on the multiple first magnetic field data; calculating multiple first displacement orientations based on multiple first displacement records corresponding to the first time interval; comparing the multiple first orientations and the multiple first displacement orientations to determine whether the magnetometer is subjected to a magnetic interference in the first time interval; and performing an avoidance operation in response to determining that the magnetometer is subjected to the magnetic interference.

[0059] In some embodiments, the flight device 1 can also detect different forms of magnetic field changes to determine whether there is magnetic interference. For a clearer explanation of the specific technical operation of the flight device 1, please refer to [reference needed]. Figure 2 This is a schematic diagram of the operation of the flight device 1 in judging magnetic interference in some embodiments of this disclosure.

[0060] First, during operation OP1, magnetometer 14 measures magnetic field data.

[0061] Next, during the operation of OP2_1, OP3_1 and OP4_1, the flight device 1 determines whether it is subject to magnetic interference based on the magnetic field changes over different time periods.

[0062] First, when the flight device 1 is subjected to magnetic interference, the magnetic field strength (i.e., magnetic field value) measured by the magnetometer 14 may change and deviate from the normal range. This may cause the flight device 1 to be unable to determine the correct orientation, or even cause the magnetometer 14 to malfunction. Therefore, during OP2_1 and OP2_2, the flight device 1 continuously checks whether the magnetic field data shows abnormal values ​​to confirm whether it is subjected to magnetic interference.

[0063] In operation OP2_1, processor 12 calculates instantaneous magnetic field strength based on magnetic field data measured by magnetometer 14.

[0064] Correspondingly, in operation OP2_2, the processor 12 determines whether the difference between the instantaneous magnetic field strength and a calibration value is too large, where the calibration value is a reasonable value for the magnetic field strength. If the difference is too large, it is determined that the magnetometer 14 may be subject to strong magnetic interference, and thus an avoidance operation is performed in operation OP5; if the difference does not exceed a certain range, it returns to operation OP1 to remeasure the magnetic field data.

[0065] It should be noted that different locations on Earth have different geomagnetic intensities, therefore the calibration values ​​must be adjusted according to the location of the flight device 1. In some embodiments, the calibration values ​​are obtained by looking up a table based on the positioning location of the flight device 1.

[0066] Specifically, the processor 12 calculates a magnetic field strength difference between one of the plurality of first magnetic field data and a calibration value, wherein the calibration value is generated based on a positioning information of the flight device; and in response to the magnetic field strength difference being greater than a first threshold, determines that the magnetometer is subject to the magnetic interference.

[0067] For example, the processor 12 calculates a resultant vector of magnetic field strength (i.e., vector) in multiple directions based on magnetic field data measured by the magnetometer 14, and uses the numerical part of the resultant vector as the instantaneous magnetic field strength.

[0068] Next, based on the location of the flight device 1, the processor 12 determines that the flight device 1 is located in Taiwan, China, and that the geomagnetic field strength in this area is 45 microtesla (µT). Therefore, 45 microtesla is used as the calibration value.

[0069] Finally, when comparing the instantaneous magnetic field strength with the calibration value, the processor 12 uses 10% of the calibration value as an acceptable difference. That is, if the absolute value of the difference between the instantaneous magnetic field strength and the calibration value exceeds 4.5 microtesla, the magnetometer 14 is determined to be subject to magnetic interference; otherwise, the magnetic field data measurement continues.

[0070] On the other hand, when the flight device 1 is subjected to magnetic interference with high magnetic field strength, such as from high-voltage power lines, the direction of the magnetic field measured by the magnetometer 14 may deviate significantly in a short period of time. This may cause the flight device 1 to momentarily lose its orientation and be unable to determine the correct location. Therefore, during operations OP3_1 to OP3_4, the flight device 1 determines whether there are abnormal directional changes in the magnetic field data within a short time interval (e.g., 1 second) to confirm whether it has been subjected to magnetic interference.

[0071] First, during operation OP3_1, the processor 12 acquires multiple magnetic field data measured at multiple time points within a relatively short time interval from the magnetometer 14.

[0072] Next, in operation OP3_2, processor 12 calculates multiple orientation directions based on the multiple magnetic field data. As mentioned above, the multiple orientation directions are used to represent the changing trend of the magnetic field direction between the multiple time points in the time interval.

[0073] Next, in operation OP3_3, processor 12 calculates multiple displacement orientations based on multiple displacement records at multiple time points within the time interval. As mentioned above, the multiple displacement orientations are used to represent the changing trend of the movement speed of flight device 1 between the multiple time points within the time interval.

[0074] In some embodiments, the flight device 1 further includes an accelerometer (not shown), such as a g-sensor in an inertial measurement unit. The accelerometer is electrically connected to the processor 12, and the plurality of displacement records can be obtained by measuring the accelerometer.

[0075] Specifically, the operation of calculating the plurality of first displacement orientations further includes: calculating the plurality of first displacement orientations based on a plurality of first acceleration values ​​measured by an accelerometer in the first time interval.

[0076] In some embodiments, the flight device 1 further includes a positioning element (not shown), such as a receiver for a Global Navigation Satellite System (GNSS). This positioning element is electrically connected to the processor 12, and the plurality of displacement records can be obtained based on the positioning information of the flight device 1, for example, by obtaining positioning information at multiple time points through a satellite navigation system.

[0077] Specifically, the operation of calculating the plurality of first displacement orientations further includes: calculating the plurality of first displacement orientations based on a plurality of positioning positions measured by a positioning element in the first time interval.

[0078] Next, in operation OP3_4, processor 12 compares the multiple orientation azimuths and multiple displacement azimuths at each time point to determine whether the azimuth difference between the two (i.e., the angle between the orientation azimuth and the displacement azimuth) remains constant. If the variation (e.g., the difference) between the multiple azimuth differences at multiple different time points is too large, it is determined that the magnetometer 14 may be subject to strong magnetic interference, and thus an avoidance operation is performed in operation OP5; if the variation does not exceed a certain value, it returns to operation OP1 to remeasure the magnetic field data.

[0079] In some embodiments, the processor 12 compares two orientation azimuths and two displacement azimuths at two different time points and calculates the azimuth differences corresponding to the two time points. If the difference between the two azimuth differences (i.e., the variability) is greater than a second threshold, it is determined whether the magnetometer 14 is subject to magnetic interference during that time interval.

[0080] Specifically, the operation of comparing the plurality of first orientation azimuths and the plurality of first displacement azimuths further includes: calculating a first azimuth difference and a second azimuth difference between the plurality of first orientation azimuths and the plurality of first displacement azimuths corresponding to the first time point and the second time point based on a first time point and a second time point in the first time interval; calculating a first variation between the first azimuth difference and the second azimuth difference; and determining whether the magnetometer is affected by the magnetic interference in the first time interval based on the first variation.

[0081] In some embodiments, when the variance is determined to exceed a threshold, to avoid misjudgment due to data errors, the processor 12 will also calculate the azimuth difference of one or more other time points in the time interval, and calculate and determine whether the variance value still exceeds the threshold. In this way, a relatively high judgment threshold can reduce the probability of misjudgment.

[0082] Specifically, the operation of comparing the plurality of first orientation azimuths and the plurality of first displacement azimuths further includes: in response to the first variation being greater than a second threshold, calculating a third position difference between the plurality of first orientation azimuths and the plurality of first displacement azimuths at the third time point based on a third time point in the first time interval; calculating a second variation between the third position difference and the first azimuth difference; and in response to the second variation being greater than the second threshold, determining that the magnetometer is subjected to the magnetic interference in the first time interval.

[0083] On the other hand, when the flight device 1 approaches an interference source with a relatively weak magnetic field strength, such as a magnetized steel bar, the direction of the magnetic field measured by the magnetometer 14 will gradually be affected and become biased over a relatively long period of time. This will still cause the error in the orientation calculation of the flight device 1 to become larger and larger. Therefore, during operation OP4_1 to OP4_4, the flight device 1 determines whether there is an abnormal change in the direction of the magnetic field data within a long time interval (e.g., 10 seconds) to confirm whether it is subject to magnetic interference.

[0084] It should be noted that, compared to operations OP3_1 to OP3_4, operations OP4_1 to OP4_4, based on magnetic field data over a relatively long time interval, determine whether the magnetic field data is biased over a longer time interval through similar operations. Therefore, the difference between operations OP3_1 to OP3_4 and operations OP4_1 to OP4_4 lies in the different magnetic field data; that is, the magnetic field data obtained by operations OP3_1 and OP4_1 correspond to different time intervals. As for operations OP4_2 to OP4_4, the flight device 1 performs operations similar to those of operations OP3_2 to OP3_4 based on the data obtained by operation OP4_1, thereby determining whether the magnetometer 14 is subject to magnetic interference over that relatively long time interval. For the sake of brevity, the similarities will not be elaborated further.

[0085] Specifically, the processor 12 further performs the following operations: receiving multiple second magnetic field data measured in a second time interval from the magnetometer, wherein the second time interval is longer than the first time interval and includes the first time interval; calculating multiple second orientations corresponding to the magnetic poles based on the multiple second magnetic field data; calculating multiple second displacement orientations based on multiple second displacement records corresponding to the second time interval; and comparing the multiple second orientations and the multiple second displacement orientations to determine whether the second time interval of the magnetometer is affected by the magnetic interference.

[0086] According to the above embodiments, the flight device 1 proposed in this disclosure can detect a variety of different interference patterns and further avoid interference sources.

[0087] In some embodiments, before flight or before the start of inspection, the flight device 1 will also perform a calibration operation to confirm that the magnetometer 14 is functioning properly.

[0088] Specifically, the processor 12 further performs the following operations: calculates a magnetic field value range based on positioning information of the flight device; performs a correction operation based on initial magnetic field data and the magnetic field value range, wherein the magnetometer measures the initial magnetic field data at a time point earlier in the first time interval; and does not calculate the plurality of first orientation directions in response to the incomplete correction operation.

[0089] For example, based on the location of the flight device 1, the processor 12 determines that the flight device 1 is located in Taiwan, China, and that the geomagnetic field strength in this area is 45 microtesla, and uses ±10% of 45 microtesla as the range of magnetic field values ​​(i.e., 40.5~49.5 microtesla).

[0090] Next, the processor 12 checks whether the magnetic field strength is within the range of magnetic field values ​​based on the magnetic field data measured by the magnetometer 14. If so, it means that the magnetometer 14 can measure the magnetic field data normally and complete the calibration operation; if not, it means that the magnetic field data measured by the magnetometer 14 is abnormal and needs to be calibrated or repaired again.

[0091] Finally, once the flight device 1 has completed its calibration operation, it can begin inspection work and simultaneously check for magnetic interference.

[0092] In some embodiments, after determining that magnetic interference has occurred, the flight device 1 estimates the location and range of the interference source based on magnetic field data measured at multiple locations, and generates an avoidance path accordingly to avoid the interference source.

[0093] Specifically, the avoidance operation includes: estimating a range and a location of an interference source based on multiple first magnetic field data corresponding to multiple locations; and generating an avoidance path based on the range and location of the interference source to control the flight device to avoid the interference source.

[0094] For example, processor 12 estimates the location of the current-carrying interference source based on magnetic field data measured at multiple different locations using the following equation.

[0095] [Formula 1]

[0096]

[0097] in Magnetic field strength (unit: microtesla). Vacuum permeability (approximately 4π × 10⁻⁶) -7 T. m / A), Current (unit: ampere). This is the shortest distance between the wire and flight device 1.

[0098] It should be noted that if the degree of magnetic field interference changes continuously when measuring at the same location, causing the magnetic field strength value to fluctuate, this may indicate that the interference source is an AC cable. In this case, the processor 12 will use the maximum magnetic field change value to estimate the location of the interference source.

[0099] Furthermore, the flight device 1 can pre-set the types of interference sources that are more likely to occur in the flight field and set relevant parameters accordingly. For example, high-voltage electrical cables 150 2 mm and 250 2 The average safe current per mm is 400 amperes, so the current value can be estimated at 400 amperes.

[0100] In this way, by measuring magnetic field data at multiple locations, the flight device 1 can estimate the location of the interference source.

[0101] In some embodiments, when the original flight path of the flight device 1 will enter an area subject to magnetic interference, the flight device 1 first estimates the location and range of the interference source, and then calculates an avoidance path that can avoid the interference source in order to reach the originally planned destination.

[0102] Specifically, the operation of generating the avoidance path further includes: determining a starting point and an ending point based on an original path; and performing at least one iterative operation to determine at least one path point based on the starting point, the ending point, the range and location of the interference source, wherein each of the at least one path point is iteratively generated based on the starting point or a previous path point, and the at least one path point connects the starting point and the ending point to form the avoidance path.

[0103] Please refer to Figures 3A to 3D This is a schematic diagram of the flight device 1 estimating the location and range of the interference source and generating an avoidance path.

[0104] First, by Figure 3A It can be seen that in the three-dimensional space formed by the x, y and z axes, the UAV DN (i.e., flight device 1) flies along the original path OR.

[0105] Next, as Figure 3B As shown, during flight, the UAV DN detects an interference source W, and its original path OR will pass through the area around the interference source W and may be subject to severe magnetic interference. At this time, the UAV DN delineates an interference zone IA around the interference source W.

[0106] In some embodiments, after the UAV DN estimates the interference source W, it estimates, based on the measured magnetic field data, the extent of magnetic interference that will occur around the interference source W (e.g., the magnetic field data and / or directional interference level is greater than a certain threshold) to delineate the interference area IA.

[0107] In some embodiments, the UAV DN defines an interference region IA by framing a preset range around the interference source W. For example, based on the interference source W, a specific distance is extended along the x, y, and z axes to generate the interference region IA.

[0108] Next, as Figure 3C As shown, the UAV DN, based on the UAV block DB formed by the fuselage, further divides the interference area IA into 3*3*3 blocks, and marks the coordinates along the x, y, and z axes as B(0, 0, 0) to B(2, 2, 2), respectively. When defining the UAV block DB, its wheelbase is taken into account. For example, if the longest wheelbase of the UAV DN fuselage is 40cm, then the size of the UAV block DB can be set to 50*50*50 cm. 3 To maintain a safe margin, the interference area IA was thus divided into 27 50*50*50 cm zones. 3 Size of the block.

[0109] Next, the UAV DN marks the multiple blocks containing the interference source W as interference blocks, namely blocks B(1, 0, 1), B(1, 1, 1) and B(1, 2, 1), while the other blocks are non-interference blocks.

[0110] In some embodiments, the UAV DN also measures magnetic field data at multiple locations around the interference zone IA, and estimates the trend of interference levels in other blocks around the interference block.

[0111] For example, when the UAV DN measures at a relatively low altitude (smaller z-axis coordinate) around the interference area IA, the magnetic field values ​​are significantly affected. Based on this, the UAV DN determines that there may be other interference sources below the interference source W and / or that interference source W significantly interferes with the area below. Therefore, the UAV DN marks the area below the interference area as a potential interference area, namely, areas B(0, 0, 0) to B(2, 2, 0).

[0112] Next, the UAV DN, based on the original path OR, marks the non-interference block where the original path OR first intersects with the interference region IA as the starting block SB(2, 1, 1) (i.e., the starting point). Correspondingly, the UAV DN, based on the original path OR, marks the non-interference block where the original path OR last intersects with the interference region IA as the ending block EB(0, 1, 1) (i.e., the ending point).

[0113] After confirming the starting block SB and the ending block EB, the UAV DN begins iterative calculations from the starting block SB, calculating the next block. This next block is adjacent to the non-interfering blocks of the previous block and is closest to the ending block EB relative to other non-interfering blocks. This iterative calculation is performed multiple times until multiple blocks connecting the starting block SB and the ending block EB are calculated, thus generating an avoidance path.

[0114] by Figure 3C For example, the avoidance path can consist of the following blocks: starting block SB(2, 1, 1), blocks B(2, 1, 2), B(1, 1, 2), B(0, 1, 2) and ending block EB(0, 1, 1).

[0115] Accordingly, Figure 3D As shown, the UAV DN was able to bypass the interference source W along the avoidance path AR and fly to its destination along the original path OR.

[0116] It should be noted that the avoidance path AR can be calculated before the UAV DN enters the interference zone IA.

[0117] In some cases, the avoidance path AR can also be that after the UAV DN enters the interference area IA, it calculates the next block to move forward step by step based on the magnetic field data measured at the moment, and finally arrives at the destination block EB.

[0118] In another embodiment, the avoidance path AR can be calculated before the UAV DN enters the interference area IA, and the path can be continuously adjusted and corrected based on the currently measured magnetic field data while flying along the avoidance path AR.

[0119] According to the above embodiment, after detecting an interference source, the flight device 1 can generate an avoidance path to evade the interference source and fly to the predetermined destination. Furthermore, by dividing the flight into blocks larger than the aircraft body, the allowable range of flight errors is increased. By advancing along the path block by block, the risk of deviating from the path due to poor positioning accuracy can be reduced.

[0120] In summary, the flight device 1 proposed in this disclosure can anticipate and avoid the risk of magnetic interference before component failure is caused by severe magnetic interference. Furthermore, through various judgment methods, the flight device 1 can detect different types of magnetic interference. Moreover, after determining the risk of magnetic interference, the flight device 1 can estimate the location and range of the interference source and generate an avoidance path to bypass the interference source and reach its destination.

[0121] Please refer to Figure 4This is a flowchart of the flight device control method 200 in the second embodiment of this disclosure. The flight device control method 200 includes steps S201 to S205. The flight device control method 200 is used to detect whether there is magnetic interference in the surrounding environment and avoid interference sources while the flight device is flying. The flight device control method 200 can be executed by a flight device (e.g., flight device 1 in the first embodiment).

[0122] First, in step S201, the flight device acquires multiple first magnetic field data measured in a first time interval.

[0123] Next, in step S202, the flight device calculates multiple first orientations corresponding to a magnetic pole based on the multiple first magnetic field data.

[0124] Next, in step S203, the flight device calculates multiple first displacement orientations based on multiple first displacement records corresponding to the first time interval.

[0125] Next, in step S204, the flight device compares the plurality of first orientation positions and the plurality of first displacement positions to determine whether the flight device is subject to a magnetic interference in the first time interval.

[0126] Finally, in step S205, in response to determining that the flight device is subjected to the magnetic interference, the flight device is controlled to perform an avoidance operation.

[0127] In some embodiments, step S203 further includes the flight device calculating the plurality of first displacement orientations based on a plurality of first acceleration values ​​measured by an accelerometer in the first time interval.

[0128] In some embodiments, step S203 further includes the flight device calculating the plurality of first displacement orientations based on a plurality of positioning positions measured by a positioning element in the first time interval.

[0129] In some embodiments, step S204 further includes the flight device calculating a first azimuth difference and a second azimuth difference corresponding to the plurality of first orientation azimuths and the plurality of first displacement azimuths based on a first time point and a second time point in the first time interval; the flight device calculating a first variation between the first azimuth difference and the second azimuth difference; and the flight device determining, based on the first variation, whether the flight device is subject to the magnetic interference in the first time interval.

[0130] In some embodiments, step S204 further includes, in response to the first variation being greater than a second threshold, the flight device calculating a third position difference between the plurality of first orientation azimuths and the plurality of first displacement azimuths corresponding to the third time point based on a third time point in the first time interval; the flight device calculating a second variation between the third position difference and the first azimuth difference; and in response to the second variation being greater than the second threshold, the flight device determining that the flight device is subjected to the magnetic interference in the first time interval.

[0131] In some embodiments, the flight device control method 200 further includes the flight device calculating a magnetic field value range based on a positioning information of the flight device; the flight device performing a correction operation based on initial magnetic field data and the magnetic field value range, wherein the flight device measures the initial magnetic field data at a time point earlier in the first time interval; and in response to the failure to complete the correction operation, the flight device does not calculate the plurality of first orientation azimuths.

[0132] In some embodiments, the flight device control method 200 further includes the flight device calculating a magnetic field strength difference between one of the plurality of first magnetic field data and a calibration value, wherein the calibration value is generated based on a positioning information of the flight device; and in response to the magnetic field strength difference being greater than a first threshold, the flight device determining that the flight device is subjected to the magnetic interference.

[0133] In some embodiments, the flight device control method 200 further includes the flight device receiving a plurality of second magnetic field data measured in a second time interval, wherein the second time interval is longer than the first time interval and includes the first time interval; the flight device calculating a plurality of second orientation azimuths corresponding to the magnetic poles based on the plurality of second magnetic field data; the flight device calculating a plurality of second displacement azimuths based on a plurality of second displacement records corresponding to the second time interval; and the flight device comparing the plurality of second orientation azimuths and the plurality of second displacement azimuths to determine whether the flight device is subjected to the magnetic interference in the second time interval.

[0134] In some embodiments, the avoidance operation includes: the flight device estimating a range and a location of an interference source based on multiple first magnetic field data corresponding to multiple locations; and the flight device generating an avoidance path based on the range and location of the interference source to control the flight device to avoid the interference source.

[0135] In some embodiments, the step of generating the avoidance path further includes: the flight device determining a starting point and an ending point based on an original path; and the flight device performing at least one iterative calculation to determine at least one path point based on the starting point, the ending point, the range of the interference source, and the location of the interference source, wherein each of the at least one path point is iteratively generated based on the starting point or a previous path point, and the at least one path point connects the starting point and the ending point to form the avoidance path.

[0136] In summary, the flight device control method 200 proposed in this disclosure can identify and avoid the risk of magnetic interference before component failure is caused by severe magnetic interference. Furthermore, the flight device control method 200 can detect different types of magnetic interference through various judgment methods. Moreover, after determining the risk of magnetic interference, the flight device control method 200 can also estimate the location and range of the interference source and generate an avoidance path to bypass the interference source and reach the destination.

[0137] Although several embodiments have been described above as examples, the flight device and control method proposed in this disclosure can also be implemented using other systems, hardware, software, storage media, or combinations thereof. Therefore, the scope of protection of this disclosure should not be limited to the specific implementations described in the embodiments of this disclosure, but should be determined by the scope defined in the appended claims.

[0138] It will be apparent to those skilled in the art to which this disclosure pertains that various modifications and variations can be made to the structure of this disclosure without departing from its scope or spirit. In view of the foregoing, the scope of protection of this disclosure also covers modifications and variations made within the appended claims.

Claims

1. A control method, characterized in that, Applicable to flight devices, the steps include: Obtain multiple first magnetic field data measured in the first time interval; Based on the multiple first magnetic field data, multiple first orientation directions of the corresponding magnetic poles are calculated; Based on multiple first displacement records corresponding to the first time interval, calculate multiple first displacement orientations; By comparing the plurality of first orientation directions and the plurality of first displacement directions, it is determined whether the flight device is subject to magnetic interference in the first time interval; as well as In response to the determination that the flight device is subjected to the magnetic interference, the flight device is controlled to perform an avoidance operation.

2. The control method as described in claim 1, characterized in that, The step of calculating the plurality of first displacement orientations further includes: The multiple first acceleration values ​​measured by the accelerometer in the first time interval are used to calculate the multiple first displacement orientations.

3. The control method as described in claim 1, characterized in that, The step of calculating the plurality of first displacement orientations further includes: The plurality of first displacement orientations are calculated based on multiple positioning positions measured by a positioning element in the first time interval.

4. The control method as described in claim 1, characterized in that, The step of comparing the plurality of first orientation positions and the plurality of first displacement positions further includes: Based on the first time point and the second time point in the first time interval, calculate the first azimuth difference and the second azimuth difference of the plurality of first orientation directions and the plurality of first displacement directions corresponding to the first time point and the second time point; Calculate the first variation between the first azimuth difference and the second azimuth difference; as well as Based on the first variation, it is determined whether the flight device is subject to the magnetic interference during the first time interval.

5. The control method as described in claim 4, characterized in that, The step of comparing the plurality of first orientation positions and the plurality of first displacement positions further includes: In response to the first variation being greater than the second threshold, the third position difference of the plurality of first orientations and the plurality of first displacements corresponding to the third time point is calculated based on the third time point in the first time interval; Calculate the second variation between the third positional difference and the first positional difference; as well as In response to the second variation being greater than the second threshold, it is determined that the flight device is subjected to the magnetic interference during the first time interval.

6. The control method as described in claim 1, characterized in that, Further includes: Based on the positioning information of the flight device, the magnetic field value range is calculated; Based on the initial magnetic field data and the magnetic field value range, a correction operation is performed, wherein the flight device measures the initial magnetic field data at a time point earlier in the first time interval; and In response to the failure to complete the correction operation, the plurality of first orientation azimuths are not calculated.

7. The control method as described in claim 1, characterized in that, Further includes: Calculate the magnetic field strength difference between one of the plurality of first magnetic field data and a calibration value, wherein the calibration value is generated based on positioning information of the flight device; and When the difference in magnetic field strength exceeds a first threshold, it is determined that the flight device is subject to magnetic interference.

8. The control method as described in claim 1, characterized in that, Further includes: The flight device receives multiple second magnetic field data measured in a second time interval, wherein the second time interval is longer than the first time interval and includes the first time interval; Based on the multiple second magnetic field data, multiple second orientations corresponding to the magnetic pole are calculated; Based on multiple second displacement records corresponding to the second time interval, multiple second displacement orientations are calculated; as well as By comparing the plurality of second orientation positions and the plurality of second displacement positions, it is determined whether the flight device is subject to the magnetic interference in the second time interval.

9. The control method as described in claim 1, characterized in that, This avoidance operation includes: Based on multiple first magnetic field data corresponding to multiple locations, the range and location of the interference source are estimated; and Based on the range and location of the interference source, an avoidance path is generated to control the flight device to avoid the interference source.

10. The control method as described in claim 9, characterized in that, The steps for generating this avoidance path further include: Based on the original path, determine the starting and ending points; and Based on the starting point, the ending point, the range of the interference source, and the location, at least one iterative operation is performed to determine at least one path point, wherein each of the at least one path point is generated iteratively based on the starting point or the previous path point, and the at least one path point connects the starting point and the ending point to form the avoidance path.

11. A flight device, characterized in that, Include: Magnetometer; as well as A processor, electrically connected to the magnetometer, performs the following operations: The magnetometer receives multiple first magnetic field data measured in a first time interval; Based on the multiple first magnetic field data, multiple first orientation directions of the corresponding magnetic poles are calculated; Based on multiple first displacement records corresponding to the first time interval, calculate multiple first displacement orientations; By comparing the plurality of first orientation positions and the plurality of first displacement positions, it is determined whether the magnetometer is subject to magnetic interference in the first time interval; as well as In response to the determination that the magnetometer is subject to magnetic interference, an avoidance operation is performed.

12. The flight device as claimed in claim 11, characterized in that, The operation of calculating the plurality of first displacement orientations further includes: The multiple first acceleration values ​​measured by the accelerometer in the first time interval are used to calculate the multiple first displacement orientations.

13. The flight device as claimed in claim 11, characterized in that, The operation of calculating the plurality of first displacement orientations further includes: The plurality of first displacement orientations are calculated based on multiple positioning positions measured by a positioning element in the first time interval.

14. The flight device as claimed in claim 11, characterized in that, The operation of comparing the plurality of first orientation positions and the plurality of first displacement positions further includes: Based on the first time point and the second time point in the first time interval, calculate the first azimuth difference and the second azimuth difference of the plurality of first orientation directions and the plurality of first displacement directions corresponding to the first time point and the second time point; Calculate the first variation between the first azimuth difference and the second azimuth difference; as well as Based on the first variation, it is determined whether the magnetometer is affected by the magnetic interference during the first time interval.

15. The flight device as claimed in claim 14, characterized in that, The operation of comparing the plurality of first orientation positions and the plurality of first displacement positions further includes: In response to the first variation being greater than the second threshold, the third position difference of the plurality of first orientations and the plurality of first displacements corresponding to the third time point is calculated based on the third time point in the first time interval; Calculate the second variation between the third positional difference and the first positional difference; as well as In response to the second variation being greater than the second threshold, it is determined that the magnetometer is subjected to magnetic interference during the first time interval.

16. The flight device as claimed in claim 11, characterized in that, The processor further performs the following operations: Based on the positioning information of the flight device, the magnetic field value range is calculated; Based on the initial magnetic field data and the range of magnetic field values, a calibration operation is performed, wherein the magnetometer measures the initial magnetic field data at a time point earlier in the first time interval; and In response to the failure to complete the correction operation, the plurality of first orientation azimuths are not calculated.

17. The flight device as claimed in claim 11, characterized in that, The processor further performs the following operations: Calculate the magnetic field strength difference between one of the plurality of first magnetic field data and a calibration value, wherein the calibration value is generated based on positioning information of the flight device; and If the difference in magnetic field strength is greater than a first threshold, it is determined that the magnetometer is subjected to magnetic interference.

18. The flight device as claimed in claim 11, characterized in that, The processor further performs the following operations: The magnetometer receives multiple second magnetic field data measured in a second time interval, wherein the second time interval is longer than the first time interval and includes the first time interval; Based on the multiple second magnetic field data, multiple second orientations corresponding to the magnetic pole are calculated; Based on multiple second displacement records corresponding to the second time interval, multiple second displacement orientations are calculated; as well as By comparing the plurality of second orientation positions and the plurality of second displacement positions, it is determined whether the magnetometer is affected by the magnetic interference in the second time interval.

19. The flight device as claimed in claim 11, characterized in that, This avoidance operation includes: Based on multiple first magnetic field data corresponding to multiple locations, the range and location of the interference source are estimated; and Based on the range and location of the interference source, an avoidance path is generated to control the flight device to avoid the interference source.

20. The flight device as claimed in claim 19, characterized in that, The operation that generates this avoidance path further includes: Based on the original path, determine the starting and ending points; and Based on the starting point, the ending point, the range of the interference source, and the location, at least one iterative operation is performed to determine at least one path point, wherein each of the at least one path point is generated iteratively based on the starting point or the previous path point, and the at least one path point connects the starting point and the ending point to form the avoidance path.

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