Unmanned aerial vehicle system and unmanned aerial vehicle based on RTK dual-antenna orientation

Abstract

The application discloses a kind of unmanned plane systems based on RTK double antenna orientation, comprising: first, second orientation equipment and controller, first, second orientation equipment and controller communication connection;First orientation equipment is configured to output first RTCM differential information to second orientation equipment, and receive the second RTCM differential information that second orientation equipment outputs is oriented to obtain the first orientation equipment solution information, wherein including first accurate heading;Second orientation equipment is configured to output second RTCM differential information to first orientation equipment, and receive the first RTCM differential information that first orientation equipment outputs is oriented to obtain the second orientation equipment solution information, wherein including second accurate heading;Controller is based on first accurate heading and / or second accurate heading generates final heading;Also provide a kind of unmanned plane.The application increases the redundancy of unmanned plane heading information, provides the selectivity of heading information, improves heading accuracy.

Description

Technical Field

[0001] This invention belongs to the field of unmanned aerial vehicle (UAV) technology, and particularly relates to an UAV system based on RTK dual-antenna orientation, a UAV heading determination method based on RTK dual-antenna orientation, and a UAV. Background Technology

[0002] Heading plays a crucial role in drone flight. It can be fused with other sensor data carried on the drone to ensure stable, accurate, and reliable flight. However, the accuracy and stability of heading can fluctuate. For example, when drones are performing fieldwork, they may be affected by environmental factors, which can impact heading accuracy and stability. These environmental factors include, but are not limited to, electromagnetic interference from high-voltage lines or towers on satellite signals, multipath effects from river, lake, or sea surfaces on satellite signals, and obstruction of satellite signals by tall buildings.

[0003] Heading determination typically employs RTK (Real-Time Kinematic) dual-antenna orientation. RTK dual-antenna orientation technology is a method for determining high-precision heading in real time using satellite data. Specifically, it involves: a main antenna connected to GNSS (Global Navigation Satellite System) device 1, serving as a rover station and designated as the first orientation device; and a secondary antenna connected to GNSS device 2, serving as a mobile base station and designated as the second orientation device. The first orientation device receives RTCM differential data from the second orientation device, performs RTK dual-antenna orientation calculations to obtain the heading, and transmits this information, including the heading, to the UAV controller via a GPS interface. The second orientation device does not perform dual-antenna orientation or transmit the heading.

[0004] The existing RTK dual-antenna technology is relatively vulnerable when the system malfunctions or encounters strong interference. There are no emergency components that can intervene to deal with interference from random external events, resulting in relatively poor stability.

[0005] The information disclosed in this background section is only intended to enhance the understanding of the background technology of this application, and therefore may include prior art that is not known to those skilled in the art. Summary of the Invention

[0006] This invention addresses the problem that existing technologies using RTK dual antennas for UAV orientation are relatively vulnerable to system failures or strong interference, have poor resistance to external random events, and are relatively unstable. The first aspect of this invention designs and provides a UAV system based on RTK dual antenna orientation, comprising: a first orientation device, a second orientation device, and a controller, wherein the first orientation device, the second orientation device, and the controller are communicatively connected; the first orientation device is configured to output first RTCM differential information to the second orientation device, and receive second RTCM differential information output by the second orientation device to perform orientation calculations to obtain first orientation device calculation information; the first orientation device calculation information includes a first precise heading; the second orientation device is configured to output second RTCM differential information to the first orientation device, and receive the first RTCM differential information output by the first orientation device to perform orientation calculations to obtain second orientation device calculation information; the second orientation device calculation information includes a second precise heading; the controller generates a final heading based on the first precise heading and / or the second precise heading.

[0007] A second aspect of the present invention provides an unmanned aerial vehicle (UAV) including a UAV controller, the UAV controller generating a final heading based on a first precise heading and / or a second precise heading; wherein the first precise heading is generated by a first orientation device communicatively connected to the UAV controller, and the second precise heading is generated by a second orientation device communicatively connected to the UAV controller; the first orientation device is configured to output first RTCM differential information to the second orientation device, and receive the second RTCM differential information output by the second orientation device to perform orientation calculation to obtain first orientation device calculation information, the first orientation device calculation information including the first precise heading; the second orientation device is configured to output second RTCM differential information to the first orientation device, and receive the first RTCM differential information output by the first orientation device to perform orientation calculation to obtain second orientation device calculation information, the second orientation device calculation information including the second precise heading.

[0008] Compared with the prior art, the advantages and positive effects of the present invention are as follows: by utilizing the second orientation device with RTK dual antennas, the redundancy of the UAV's heading information is increased, which to some extent solves the problems of insufficient utilization of the UAV's RTK dual antenna orientation device and the inability to guarantee heading accuracy and stability; at the same time, the use of the first orientation device and the second orientation device provides selectivity for heading information, and the fusion of multiple information improves the accuracy of heading information.

[0009] Other features and advantages of the present invention will become clearer after reading the detailed embodiments of the invention in conjunction with the accompanying drawings. Attached Figure Description

[0010] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is a schematic diagram of the structure of an RTK-based dual-antenna directional unmanned aerial vehicle system provided in some embodiments of the present invention;

[0012] Figure 2 A flowchart of an RTK-based dual-antenna directional unmanned aerial vehicle system provided in some embodiments of the present invention;

[0013] Figure 3 A flowchart of an RTK-based dual-antenna directional unmanned aerial vehicle system provided in some embodiments of the present invention;

[0014] Figure 4 This is a flowchart of an RTK-based dual-antenna directional unmanned aerial vehicle system provided in some embodiments of the present invention. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0016] It should be noted that in the description of this invention, the terms "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," which indicate directional or positional relationships, are based on the directional or positional relationships shown in the accompanying drawings. These are merely for ease of description and do not indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0017] To address the issues of vulnerability in existing RTK dual-antenna drone orientation systems, which are relatively weak in the face of malfunctions or strong interference, poor resistance to random external events, and overall low stability, such as... Figure 1As shown, some embodiments of the present invention design and provide an RTK-based dual-antenna directional unmanned aerial vehicle (UAV) system. The UAV system comprises a first directional device 100, a second directional device 200, and a controller 300. The first directional device 100, the second directional device 200, and the controller 300 are preferably connected via a UART (Universal Asynchronous Receiver / Transmitter) interface. The controller 300 may be an onboard processing module of the UAV, including a processor and a memory for storing instructions. The processor executes the instructions in the memory to perform any of the methods disclosed herein. In one example, the controller 300 may store and execute flight control logic, including the UAV's heading. The controller 300 may also be a processor in another terminal device communicatively connected to the processing module; the terminal device may be a remote controller or computer adapted to the UAV. Both the first directional device 100 and the second directional device 200 may be GNSS (Global Navigation Satellite System) devices.

[0018] In this embodiment, the first orientation device 100 is configured to input first RTCM differential information to the second orientation device 200. The Radio Technical Commission for Maritime Services (RTCM) has specified the Differential Global Navigation System Service Standard to facilitate the exchange and processing of differential data. The first RTCM differential information conforms to the Differential Global Navigation System Service Standard format. On the other hand, the first orientation device 100 receives the second RTCM differential information output by the second orientation device 200 and performs orientation calculations on the second RTCM differential information output by the second orientation device 200 to obtain the first orientation device 100's calculated information, which includes a first precise heading.

[0019] Correspondingly, the second orientation device 200 is configured to output second RTCM differential information to the first orientation device 100. The second RTCM differential information also conforms to the differential global navigation system service standard format. On the other hand, the second orientation device 200 receives the first RTCM differential information output by the first orientation device 100 and performs orientation calculations on the first RTCM differential information output by the first orientation device 100 to obtain the second orientation device 200's calculated information, which includes a second precise heading.

[0020] The controller 300 generates a final course based on a first precise course and / or a second precise course.

[0021] In the above embodiments, by utilizing the second orientation device 200 with RTK dual antennas, the redundancy of the UAV's heading information is increased, which to some extent solves the problems of insufficient utilization of the UAV's RTK dual antenna orientation device and the inability to guarantee heading accuracy and stability; at the same time, the use of the first orientation device 100 and the second orientation device 200 provides selective multi-information fusion of heading information, which improves the accuracy of the heading information.

[0022] Figure 2 This is a flowchart illustrating the execution of a controller 300 in an unmanned aerial vehicle (UAV) system provided in some embodiments of this application. In some embodiments of this application, the first orientation device 100's solution information further includes a first solution type, and the second orientation device 200's solution information further includes a second solution type.

[0023] Specifically, it includes the following steps:

[0024] Step S101: Read the first solution type. The first solution type corresponds to the solution status of the first orientation device 100, and may include unsolved, single-point positioning solution, DGNSS solution, RTK floating-point solution, and RTK fixed solution. A data bit can be set in the first orientation device 100 to represent the first solution type; that is, the first solution type can be obtained by reading the stored value of the data bit. For example, as shown in Table 1:

[0025] <![CDATA[The first calculation type q1]]> Solution status 1 Unsolved 2 Single-point positioning solution 3 DGNSS solution 4 RTK floating-point calculation 5 RTK fixed solution

[0026] Table 1

[0027] For example, when q1 is read, the first orientation device 100 performs RTK fixed calculation.

[0028] Step S102: Read the second solution type. The second solution type corresponds to the solution status of the second orientation device 200, and may include: no solution, single-point positioning solution, DGNSS solution, RTK floating-point solution, and RTK fixed solution, etc. A data bit can be set in the second orientation device 200 to represent the solution status of the second orientation device 200, that is, the second solution type can be obtained by reading the stored value of the data bit. For example, as shown in Table 1:

[0029] <![CDATA[Second calculation type q2]]> Solution status 1 Unsolved 2 Single-point positioning solution 3 DGNSS solution 4 RTK floating-point calculation 5 RTK fixed solution

[0030] Table 2

[0031] Step S103: Determine whether the first solution type is an RTK fixed solution.

[0032] Step S104: If the first solution type is RTK fixed solution, i.e. q1≡5, then further determine whether the second solution type is RTK fixed solution.

[0033] Step S105: If the second solution type is a non-RTK fixed solution, i.e. q2≠5, then the first precise heading is used as the final heading. Where ψ is the final heading. The first precise heading has been determined; the process is now complete.

[0034] Step S106: If the first solution type is a non-RTK fixed solution, i.e. q1≠5, then further determine whether the second solution type is an RTK fixed solution.

[0035] Step S107: If the second solution type is RTK fixed solution, i.e. q2≡5, then the second precise heading is used as the final heading. in The second precise course has been determined, and the process is now complete.

[0036] In other words, the accurate heading generated by the fixed RTK solution is selected as the final heading to improve the accuracy of the heading information.

[0037] Step S108: If the first solution type is RTK fixed solution, i.e. q1≡5, and the second solution type is RTK fixed solution, i.e. q2≡5, then optionally, the final course is generated based on the first precise course, or based on the first precise course and the second precise course.

[0038] Specifically, in some embodiments of this application, if both the first solution type and the second solution type are RTK fixed solutions, the controller 300 also performs the following when generating the final heading: Figure 3 The steps are shown.

[0039] Step S201: Calculate the precise heading deviation between the first precise heading and the second precise heading, where the precise heading deviation Δψ r satisfy

[0040] Step S202: Determine whether the precise heading deviation is less than the maximum allowable error.

[0041] Step S203: If the precise heading deviation is less than the maximum allowable error, i.e. Δψ r If ξ < ξ, then the first precise heading is taken as the final heading, i.e. The process is complete.

[0042] In some optional embodiments of this application, if the precise heading deviation is less than the maximum allowable error, the second precise heading can also be used as the final heading. This indicates that external interference is relatively weak, and either selected precise heading can satisfy a certain degree of accuracy.

[0043] Step S204: If the precise heading deviation is greater than or equal to the maximum allowable error, it indicates that the external interference is relatively strong at this time. The final heading is generated based on the first precise heading and the second precise heading.

[0044] Specifically, in some embodiments of this application, generating the final heading based on the first precise heading and the second precise heading specifically includes: calling the first velocity information and the first baseline calculation variance from the information calculated by the first orientation device 100; and calling the information calculated by the second orientation device 200 further includes the second velocity information and the second baseline calculation variance; wherein the first velocity information includes the velocity in the northeast coordinate system, denoted as... The second velocity information includes the velocity in the northeast coordinate system, denoted as... In the northeast coordinate system, the N-axis points north of the Earth, the E-axis points east of the Earth, and the D-axis is perpendicular to the Earth's surface and points downwards. n, e, and d represent the N, E, and D axes, respectively.

[0045] Also includes, for example Figure 4 The following steps are shown:

[0046] Step S301: Calculate the first ground heading of the first orientation device 100 based on velocity.

[0047] First ground-to-head direction satisfy:

[0048] Step S302: Calculate the second ground heading of the second orientation device 200 based on velocity.

[0049] Second ground course satisfy:

[0050] Step S303: Perform low-pass filtering on the first and second ground headings, and adjust the value range of the first and second ground headings to the range of 0° to 360° respectively.

[0051] Step S304: Calculate the heading deviation Δψ1 of the first orientation device. The heading deviation Δψ1 of the first orientation device satisfies:

[0052] Step S305: Calculate the heading deviation Δψ2 of the second orientation equipment; the heading deviation Δψ2 of the second orientation equipment satisfies:

[0053] Step S306: Determine whether the first horizontal velocity meets the preset horizontal velocity condition: The first horizontal velocity is:

[0054] Step S307: If the first horizontal velocity meets the preset horizontal velocity condition, then further determine whether the second horizontal velocity meets the preset horizontal velocity condition. The second horizontal velocity is:

[0055] Step S308: When both the first horizontal speed and the second horizontal speed meet the preset horizontal speed conditions, determine the heading deviation weight of the first orientation device and the heading deviation weight of the second orientation device based on the heading deviation of the first orientation device and the heading deviation of the second orientation device.

[0056] Step S309: Determine the baseline calculation weights of the first orientation device and the second orientation device based on the variance of the first baseline calculation and the variance of the second baseline calculation;

[0057] Step S310: Set the heading deviation weighting coefficient and the baseline solution weighting tuning coefficient;

[0058] Step S311: Calculate the heading fusion weight of the first orientation device 100 and the heading fusion weight of the second orientation device;

[0059] Step S312: Generate the final heading based on the first precise heading, the second precise heading, the heading fusion weight of the first orientation device 100, and the heading fusion weight of the second orientation device.

[0060] In the above method, the deviation between the precise heading and the ground heading is used to determine the heading deviation weight, which is then used as one of the final heading fusion weight factors. This increases the reliability and robustness of the weighted fusion result of the first and second precise headings during heading fusion. Furthermore, information such as heading deviation and baseline solution variance is used to determine the heading fusion weight, and tuning coefficients for the heading deviation weight and baseline solution weight are added. The emphasis of the heading deviation weight and baseline solution weight is adaptively adjusted based on experience, considering both the accuracy and precision of the heading. This makes the fused heading weight more consistent with the actual situation, further improving the stability of the heading information and optimizing the heading accuracy and precision of dual-antenna orientation.

[0061] In some optional embodiments of this application, a first-order low-pass filter formula is used to perform low-pass filtering on the first ground pair heading, wherein:

[0062] in, This represents the filtering result for the (k-1)th filtering cycle. This represents the real-time sampled value of the first ground heading during the k-th filtering cycle. α1 is the low-pass filter output for the first ground-to-head trajectory in the k-th cycle; α1 is the first filter coefficient.

[0063] Correspondingly, a first-order low-pass filter formula is used to perform low-pass filtering on the second ground heading, where:

[0064] in, This represents the filtering result for the (k-1)th filtering cycle. This represents the real-time sampled value of the second ground heading during the k-th filtering cycle. α1 is the low-pass filter output for the first ground-to-ground heading; α2 is the second filter coefficient.

[0065] Low-pass filtering improves the stability and accuracy of ground-based heading.

[0066] In some optional embodiments of this application, when both the first horizontal speed and the second horizontal speed meet a preset horizontal speed condition, the weights of the first and second orientation equipment heading deviations are determined using an inverse variance weighting method based on the heading deviations of the first and second orientation equipment, including the following steps. For example, if the first horizontal speed... And the second horizontal velocity Then both the first horizontal velocity and the second horizontal velocity satisfy the preset horizontal velocity condition.

[0067] Calculate the square of the heading deviation of the first orientation device, denoted as

[0068] Calculate the square of the heading deviation of the second orientation device, denoted as

[0069] Calculate the sum of the squares of the heading deviation of the first orientation device and the reciprocals of the squares of the heading deviation of the second orientation device, denoted as . satisfy:

[0070] Calculate the heading deviation weight of the first orientation device satisfy:

[0071] Calculate the heading deviation weight of the second orientation equipment satisfy:

[0072] in,

[0073] In some optional embodiments of this application, when the first horizontal velocity or the second horizontal velocity does not meet the preset horizontal velocity condition, i.e. or Sometimes,

[0074] The inverse deviation weighting method is used to determine the heading deviation weight. The reciprocal of the square of the deviation reflects the accuracy of the heading information of the orientation equipment. If the deviation is larger, the reciprocal of the square of the deviation is smaller, the weight is smaller, and the heading is less accurate; and vice versa. This will not be elaborated further here.

[0075] In some optional embodiments of this application, the controller 300 is configured to perform the following steps when determining the first orientation device baseline calculation weight and the second orientation device baseline calculation weight based on the first baseline calculation variance and the second baseline calculation variance:

[0076] Calculate the sum of the reciprocals of the squares of the variances of the first and second baseline solutions, denoted as . in

[0077] Calculate the baseline solution weights for the first orientation device. satisfy:

[0078] Calculate the baseline solution weights for the second orientation device. satisfy:

[0079] in,

[0080] The reciprocal of the baseline solution variance reflects the accuracy of the heading information of the orientation equipment. If the variance is larger, the smaller the reciprocal of the square of the mapped variance, the smaller its weight, and the worse the accuracy. Conversely, the smaller the variance, the lower the accuracy. This will not be elaborated further here.

[0081] In some optional embodiments of this application, the controller 300 is configured to perform the following steps when calculating the heading fusion weight of the first orientation device 100 and the heading fusion weight of the second orientation device:

[0082] Calculate the heading fusion weight P1 of the first orientation device. The heading fusion weight P1 of the first orientation device satisfies:

[0083]

[0084] Calculate the heading fusion weight P2 of the second orientation equipment. The heading fusion weight P2 of the second orientation equipment satisfies:

[0085]

[0086] Where λ is the heading deviation weight tuning coefficient and β is the baseline solution weight tuning coefficient, the heading deviation weight tuning coefficient and the baseline solution weight tuning coefficient satisfy λ+β=1. Introducing the heading deviation weight tuning coefficient and the baseline solution weight tuning coefficient allows for adaptive adjustment of the emphasis of the heading deviation weight and the baseline solution weight based on experience, taking into account both the accuracy and precision of the heading, making the fused heading weight more consistent with the actual situation.

[0087] In some optional embodiments of this application, the controller 300 is configured to perform the following steps when generating a final heading based on a first precise heading, a second precise heading, a first orientation device heading fusion weight, and a second orientation device heading fusion weight:

[0088] Calculate the final heading ψ:

[0089] The final course ψ satisfies

[0090] A second aspect of this application provides a drone, the drone including a drone controller that generates a final heading based on a first precise heading and / or a second precise heading;

[0091] The first precise heading is generated by a first orientation device that is communicatively connected to the UAV controller, and the second precise heading is generated by a second orientation device that is communicatively connected to the UAV controller.

[0092] The first orientation device is configured to output first RTCM differential information to the second orientation device, and receive the second RTCM differential information output by the second orientation device to perform orientation calculation to obtain the first orientation device calculation information, the first orientation device calculation information including a first precise heading;

[0093] The second orientation device is configured to output second RTCM differential information to the first orientation device, and to receive the first RTCM differential information output by the first orientation device to perform orientation calculation to obtain the second orientation device's calculation information, which includes a second precise heading.

[0094] That is, the first orientation device and the second orientation device perform RTK orientation calculations simultaneously.

[0095] In some embodiments of this application, the first orientation device and the second orientation device are cross-connected via a UART interface; the first orientation device and the second orientation device send their respective RTCM differential information to each other; after receiving the RTCM differential information sent by the other party, the first orientation device and the second orientation device independently perform RTK orientation calculation.

[0096] The information calculated by the first orientation device is the first orientation information, which includes the first solution type, the first velocity information, the first precise heading sent from the second orientation device to the first orientation device, and the first baseline solution variance; wherein the first solution type is denoted as q1, and the first velocity information is denoted as... The first precise heading is denoted as The variance of the first baseline solution is denoted as... The orientation information is represented in the Northeast-Eastern (NED) coordinate system, with the N-axis pointing north to Earth, the E-axis pointing east to Earth, and the D-axis perpendicular to the Earth's surface and pointing downwards. The superscripts n, e, and d represent the three NED axes, respectively.

[0097] The second orientation information, calculated by the second orientation device, includes the second orientation type, second velocity information, the second precise heading sent from the first orientation device to the second orientation device, and the second baseline calculation variance. The second orientation type is denoted as q2, and the second velocity information is denoted as... The second precise heading is denoted as The variance of the second baseline solution is denoted as... The orientation information is represented in the Northeast-Eastern (NED) coordinate system, with the N-axis pointing north to Earth, the E-axis pointing east to Earth, and the D-axis perpendicular to the Earth's surface and pointing downwards. The superscripts n, e, and d represent the three NED axes, respectively.

[0098] The first and second orientation devices are respectively connected to the UART interface or GPS module of the UAV controller to output first and second orientation information to the UAV controller.

[0099] The drone controller performs the following steps:

[0100] Step S10: Calculate the first ground heading of the first orientation device based on speed, and calculate the second ground heading of the second orientation device based on speed.

[0101] The first heading relative to the ground is represented as: The second heading relative to the ground is represented as follows:

[0102] Low-pass filtering is applied to the first and second ground headings respectively, and the range of the ground heading angle is adjusted to be within the range of 0° to 360°.

[0103] Specifically, this includes: applying a first-order low-pass filter formula to the first ground heading for low-pass filtering, where:

[0104] in, This represents the filtering result for the (k-1)th filtering cycle. This represents the real-time sampled value of the first ground heading during the k-th filtering cycle. α1 is the low-pass filter output for the first ground-to-head trajectory in the k-th cycle; α1 is the first filter coefficient.

[0105] Correspondingly, a first-order low-pass filter formula is used to perform low-pass filtering on the second ground heading, where:

[0106] in, This represents the filtering result for the (k-1)th filtering cycle. This represents the real-time sampled value of the second ground heading during the k-th filtering cycle. α1 is the low-pass filter output for the first ground-to-ground heading; α2 is the second filter coefficient.

[0107] Step S11: Calculate the precise heading deviation. The precise heading deviation is the difference between the first precise heading and the second precise heading, expressed as:

[0108] Step S12: Calculate the heading deviation of the first orientation device. The heading deviation of the first orientation device is expressed as:

[0109] Step S13: Calculate the heading deviation of the second orientation device. The heading deviation of the second orientation device is expressed as:

[0110] Step S14: Read the first solution type q1.

[0111] During the calculation, the first orientation device can have the following calculation states: uncalculated, single-point positioning calculation, DGNSS calculation, RTK floating-point calculation, and RTK fixed calculation, and the corresponding code is used as the first calculation type q1. For example, as shown in Table 1:

[0112]

[0113]

[0114] Step S15: Read the second solution type q2.

[0115] During the calculation, the second orientation device can have the following calculation states: uncalculated, single-point positioning calculation, DGNSS calculation, RTK floating-point calculation, and RTK fixed calculation, and the corresponding code is used as the second calculation type q2. Examples are shown in Table 2:

[0116] <![CDATA[Second calculation type q2]]> Solution status 1 Unsolved 2 Single-point positioning solution 3 DGNSS solution 4 RTK floating-point calculation 5 RTK fixed solution

[0117] Step S16: If the first solution type q1 read is an RTK fixed solution and the second solution type q2 read is a non-RTK fixed solution, then the final heading is obtained as follows: If the first solution type q1 read is a non-RTK fixed solution while the second solution type q2 read is an RTK fixed solution, then the final heading is obtained as follows: If the first solution type q1 read is an RTK fixed solution and the second solution type q2 read is also an RTK fixed solution, then proceed to step S.

[0118] Specifically, following the examples in Tables 1 and 2, the steps above are as follows: If q1≡5 and q2≠5, then the final course... End the processing flow; if q1≠5 and q2≡5, then the final course is... End the processing flow; if q1≡5 and q2≡5, continue to execute step S.

[0119] Step S17: Utilize the precise heading deviation Δψ r Determine the consistency of the precise heading. If Δψ r If ξ < ξ, then continue with step S; if Δψ r If ≥ξ, then the final heading is set as End the processing flow; where ξ is the maximum allowable error for precise heading deviation, and ξ can be a set constant.

[0120] Step S18: Determine whether the horizontal speed meets the preset horizontal speed conditions.

[0121] Specifically, the first level speed satisfy

[0122] Second horizontal speed satisfy

[0123] If and If the horizontal speed meets the preset horizontal speed condition, proceed to step S19; otherwise, proceed to step S20.

[0124] Step S19: Based on the heading deviation Δψ1 of the first orientation equipment and the heading deviation Δψ2 of the second orientation equipment, determine the weight P1 of the heading deviation of the first orientation equipment using the inverse variance weighting method. h Second orientation equipment heading deviation weight

[0125] Specifically, the following steps are included:

[0126] Calculate the square of the heading deviation of the first orientation device, denoted as

[0127] Calculate the square of the heading deviation of the second orientation device, denoted as

[0128] Calculate the sum of the squares of the heading deviation of the first orientation device and the reciprocals of the squares of the heading deviation of the second orientation device, denoted as . have

[0129] Calculate the heading deviation weight P1 of the first orientation device. h ,

[0130] Calculate the heading deviation weight of the second orientation equipment

[0131] in,

[0132] Step S20: Calculate the variance based on the first baseline and record it as follows. Second baseline solution variance The baseline solution weight P1 of the first orientation device is determined using the inverse variance weighting method. l Second orientation equipment baseline solution weight

[0133] Specifically, the following steps are included:

[0134] Calculate the sum of the reciprocals of the squares of the variances of the first and second baseline solutions, denoted as . have

[0135] Calculate the baseline solution weight P1 for the first orientation device. l ,

[0136] Calculate the baseline solution weights for the second orientation device.

[0137] in,

[0138] Step S21: Set the heading deviation weight tuning coefficient λ and the baseline solution weight tuning coefficient β, wherein the heading deviation weight tuning coefficient λ and the baseline solution weight tuning coefficient β satisfy λ+β=1.

[0139] Step S22: Determine the heading fusion weight P1 and the heading fusion weight P2 of the first orientation device, where:

[0140] The first orientation equipment heading fusion weight P1 satisfies

[0141] The second orientation equipment heading fusion weight P2 satisfies

[0142] when or Sometimes,

[0143] Step S23: Determine the final course. The final course is...

[0144] The UAV provided in this embodiment has better heading accuracy and stability.

[0145] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions claimed by the present invention.

Claims

1. An unmanned aerial system based on RTK dual antenna orientation, characterized in that, include: A first orientation device, a second orientation device, and a controller are communicatively connected; The first orientation device is configured to output first RTCM differential information to the second orientation device, and receive second RTCM differential information output by the second orientation device to perform orientation calculation to obtain the first orientation device calculation information; The first orientation device calculates the following information: a first precise heading. The second orientation device is configured to output second RTCM differential information to the first orientation device, and receive the first RTCM differential information output by the first orientation device to perform orientation calculation to obtain the second orientation device calculation information; The second orientation device's calculated information includes a second precise heading; The controller generates a final course based on the first precise course and the second precise course.

2. The RTK-based dual-antenna directional UAV system according to claim 1, characterized in that, The first orientation device solution information further includes a first solution type, and the second orientation device solution information further includes a second solution type; When the controller generates the final heading, it performs the following steps: Read the first solution type; Read the second solution type; If the first solution type is RTK fixed solution and the second solution type is non-RTK fixed solution, then the first precise heading is used as the final heading; if the first solution type is non-RTK fixed solution and the second solution type is RTK fixed solution, then the second precise heading is used as the final heading.

3. The RTK-based dual-antenna directional UAV system according to claim 2, characterized in that, If both the first solution type and the second solution type are RTK fixed solutions, the controller further performs the following steps when generating the final heading: calculating a precise heading deviation between the first precise heading and the second precise heading; wherein the precise heading deviation satisfies wherein is the first precise heading, is the second precise heading; If the precise heading deviation is less than the maximum allowable error, then the first precise heading is taken as the final heading.

4. The RTK-based dual-antenna directional UAV system according to claim 3, characterized in that, The first orientation device's solution information also includes first velocity information and first baseline solution variance; the second orientation device's solution information also includes second velocity information and second baseline solution variance, wherein the first velocity information includes velocity in the northeast coordinate system, denoted as... The second velocity information includes the velocity in the northeast coordinate system, denoted as... ; If the precise heading deviation is not less than the maximum allowable error, the controller further performs the following steps when generating the final heading: calculating a first groundspeed-based heading for the first directional device , the first groundspeed-based heading satisfies: ； calculating a second ground track based on velocity for the second directional device , the second ground track satisfies: ； Low-pass filtering is applied to the first and second ground headings to adjust their values ​​to the range of 0° to 360°. Calculate the heading deviation of the first orientation device The first orientation device's heading deviation satisfy: ; Computing a second orientation device heading deviation ; the second orientation device heading deviation satisfies: ; When both the first horizontal speed and the second horizontal speed meet the preset horizontal speed condition, the heading deviation weights of the first and second orientation devices are determined based on the heading deviations of the first and second orientation devices; wherein: the first horizontal velocity is: the second horizontal velocity is: ; The baseline calculation weights of the first orientation device and the second orientation device are determined based on the first baseline calculation variance and the second baseline calculation variance. Set the heading deviation weighting coefficient and the baseline solution weighting tuning coefficient; Calculate the heading fusion weight of the first orientation device and the heading fusion weight of the second orientation device; The final heading is generated based on the first precise heading, the second precise heading, the first orientation device heading fusion weight, and the second orientation device heading fusion weight.

5. The RTK-based dual-antenna directional UAV system according to claim 4, characterized in that, The first ground-to-ground heading is low-pass filtered using a first-order low-pass filter formula, where: ;in, This represents the filtering result for the (k-1)th filtering cycle. This represents the real-time sampled value of the first ground heading during the k-th filtering cycle. This is the low-pass filter output for the first ground heading in the k-th cycle; The first filter coefficient; The second ground heading is low-pass filtered using a first-order low-pass filter formula, where: ; wherein, is the filtering result of the k-1th filtering period, is the real-time sampling value of the second ground track in the kth filtering period, is the low-pass filtering output of the second ground track; is the second filtering coefficient.

6. The RTK-based dual-antenna directional UAV system according to claim 4, characterized in that, The controller is also configured to perform the following steps: if the first horizontal speed and the second horizontal speed then the first horizontal speed and the second horizontal speed both satisfy the preset horizontal speed condition, and the first directional device heading deviation weight and the second directional device heading deviation weight are determined by using inverse variance weighting method according to the first directional device heading deviation and the second directional device heading deviation, comprising the following steps: square the first heading deviation of the directional device, denoted as ; Calculate the square of the heading deviation of the second orientation device, denoted as ; The sum of the square of the first directional device heading deviation and the inverse of the square of the second directional device heading deviation is calculated, denoted as , satisfies: ; calculating the first directional device heading deviation weight , satisfies: ; calculating the second orientation device heading deviation weight , satisfies: ; wherein .

7. The RTK-based dual-antenna directional UAV system according to claim 6, characterized in that, The controller is configured to perform the following steps when determining the first orientation device baseline calculation weight and the second orientation device baseline calculation weight based on the first baseline calculation variance and the second baseline calculation variance: Calculate the sum of the reciprocals of the squares of the variances of the first baseline solution and the variances of the second baseline solution, denoted as . ;in ; computing the first orientation device baseline solution weight , satisfies: ; computing the second orientation device baseline solution weight , satisfies: ; wherein , is a first baseline solution variance, is a second baseline solution variance.

8. The RTK-based dual-antenna directional UAV system according to claim 7, characterized in that, The controller is configured to perform the following steps when calculating the first orientation device heading fusion weight and the second orientation device heading fusion weight: calculating the first orientation device heading fusion weight , the first orientation device heading fusion weight satisfies: ； calculating the second orientation device heading fusion weight , the second orientation device heading fusion weight satisfies: ： where λ is the heading bias weight tuning coefficient, β is the baseline solution weight tuning coefficient, the heading bias weight tuning coefficient and the baseline solution weight tuning coefficient satisfy .

9. The RTK-based dual-antenna directional UAV system according to claim 8, characterized in that, When the controller is configured to generate the final heading based on a first precise heading, a second precise heading, a first orientation device heading fusion weight, and a second orientation device heading fusion weight, it performs the following steps: Calculate the final heading ψ: The final heading ψ satisfies .

10. A drone, comprising a drone controller, characterized in that, The UAV controller generates a final heading based on a first precise heading and a second precise heading. Wherein, the first precise heading is generated by a first orientation device that is communicatively connected to the UAV controller, and the second precise heading is generated by a second orientation device that is communicatively connected to the UAV controller; The first orientation device is configured to output first RTCM differential information to the second orientation device, and receive second RTCM differential information output by the second orientation device to perform orientation calculation to obtain first orientation device calculation information, wherein the first orientation device calculation information includes the first precise heading; The second orientation device is configured to output second RTCM differential information to the first orientation device, and to receive the first RTCM differential information output by the first orientation device to perform orientation calculation to obtain second orientation device calculation information, wherein the second orientation device calculation information includes the second precise heading.

Images