A target search control instruction planning method for a drone nacelle

Abstract

The application discloses a target search control instruction planning method of a UAV pod, and comprises the following steps: presetting a coordinate system, collecting first operation information, second operation information and third operation information, and simultaneously acquiring the slant range of an imager along a sight axis to the ground; subsequently, setting a "row" search instruction planning speed according to a bias trigonometric function form, and then calculating a "row" scanning planning angular velocity; finally, calculating a first component and a compensation angular velocity according to the collected data, and the calculation of the compensation angular velocity can effectively isolate the interference of the UAV search, so that the target search control speed instruction is more accurate, and the problems of imaging blur and easy omission of ground scenes in the search process are solved.

Description

Technical Field

[0001] This disclosure generally relates to target search and imaging using an unmanned aerial vehicle (UAV) pod array detection system, and more specifically to a method for planning target search control commands for an UAV pod. Background Technology

[0002] Small unmanned aerial vehicle (UAV) pods typically employ area array imagers for image acquisition, which, in conjunction with the UAV's flight, probe designated areas and perform target search and imaging on the ground. To ensure clear imaging, the line of sight must remain pointing towards a fixed area within the Earth coordinate system during each imager integration cycle.

[0003] During image acquisition at different locations, factors such as the aircraft's attitude and forward flight motion make it difficult to precisely control the search process without planning the scanning commands. This can lead to image shifts at desired imaging locations, causing image blurring. Furthermore, it can result in varying degrees of overlap between image "columns" and "rows" along the flight direction and perpendicular to it, leading to omissions and incomplete coverage of ground features. To address these issues, we provide a target search control command planning method for UAV pods. Summary of the Invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, it is desirable to provide a target search control command planning method for UAV pods that produce blurred and complete images during the search process.

[0005] Firstly, this application provides a target search control command planning method for an unmanned aerial vehicle (UAV) pod, the target search control command planning method comprising the following steps:

[0006] A preset coordinate system is provided, which includes the Earth coordinate system, the inertial coordinate system, the pod base coordinate system, and the line-of-sight coordinate system.

[0007] The first operational information of the UAV pod is collected by the attitude measurement module of the UAV; the first operational information includes the roll, pitch and yaw attitude angles of the UAV and the three linear velocities of the UAV: ​​north speed, east speed and vertical speed.

[0008] The second operational information of the UAV pod is collected by the inertial angular velocity sensor measurement module of the UAV pod; the second operational information includes the roll angular velocity and pitch angular velocity of the imager's line of sight;

[0009] The third operational information of the UAV pod is collected by the UAV pod frame angle measurement module; the third operational information includes the roll angle and pitch angle of the imager's line of sight.

[0010] The slant distance from the imager along the line of sight to the ground is obtained by the ranging device inside the slant distance UAV pod;

[0011] Set the planning speed for the "row" search instruction, and the planning speed for the row search instruction is planned using the form of an offset trigonometric function;

[0012] The angular velocity of the "row" scan planning is obtained, which is calculated based on the planning velocity of the "row" search instruction;

[0013] The first component of the UAV's velocity relative to the Earth in the line-of-sight coordinate system is obtained, and the first component is calculated from the first operational information and the second operational information.

[0014] The compensation angular velocity required for the aircraft to fly along the Earth's surface is calculated, and the compensation angular velocity is obtained by the first component and the slant distance from the imager along the line of sight to the ground.

[0015] Generate a target search control speed command for the UAV pod and input it to the servo control terminal. The target search command is calculated from the "line" scan planning angular velocity and the compensation angular velocity.

[0016] According to the technical solution provided in the embodiments of this application, it further includes generating a data update instruction, which is used to update the first operating information, the second operating information, and the third operating information in real time; generating the data update instruction includes the following steps:

[0017] Obtain the first transfer matrix, which is acquired by the UAV pod frame angle measurement module; the first transfer matrix is ​​the transfer matrix from the pod base coordinate system to the line-of-sight coordinate system;

[0018] The second transfer matrix is ​​obtained by the pose measurement module; the second transfer matrix is ​​the transfer matrix from the inertial coordinate system to the pod base coordinate system.

[0019] A data update instruction is generated, which is calculated from the first transition matrix and the second transition matrix.

[0020] According to the technical solution provided in the embodiments of this application, the angular velocity of the "row" scanning plan is calculated according to the following formula:

[0021]

[0022]

[0023] Where A is the required "line" search angle of the pod perpendicular to the flight path; L is the depth of the imager's imaging on the ground along the flight path; and V is the UAV's flight speed during the search operation. ω represents the component of the infrared detector's angular velocity vector in the Earth coordinate system within the detector's line-of-sight coordinate system. S Plan the speed for the "line" search command.

[0024] According to the technical solution provided in the embodiments of this application, the first component is calculated according to the following formula:

[0025]

[0026]

[0027] Among them, [v1 v2 v3] T Let v be the first component of the drone's velocity relative to the Earth in the line-of-sight coordinate system; n For the North Speed ​​of Unmanned Aerial Vehicles; v e For the Dongsu drone; v v For the vertical speed of the drone; The first transfer matrix is ​​determined by the roll angle and pitch angle of the imager's line of sight; The second transfer matrix is ​​determined by the UAV's roll attitude angle, pitch attitude angle, and yaw attitude angle. This is the transition matrix from the inertial coordinate system to the line-of-sight coordinate system, which is the basis for data update commands.

[0028] According to the technical solution provided in the embodiments of this application, the compensated angular velocity is calculated using the following formula:

[0029]

[0030] in, To compensate for angular velocity; r l This is the slant distance from the imager along the line of sight to the ground.

[0031] According to the technical solution provided in the embodiments of this application, the target search control command for the UAV pod is calculated according to the following formula:

[0032]

[0033]

[0034] in, Provides speed control commands for target search on the UAV pod.

[0035] According to the technical solution provided in the embodiments of this application, the coordinate system is preset according to the following rules:

[0036] The origin of the Earth coordinate system is at the geometric center of the Earth. Its X-axis points to the intersection of the 0-degree longitude and 0-degree latitude, the Z-axis points north through the polar axis, and the Y-axis is obtained by the right-hand rule.

[0037] The origin of the inertial coordinate system is within the navigation system, and its X-axis points to true north; Z... N The axis points to the earth, X N With Z N Vertical, Y N Determined by the right-hand rule;

[0038] The origin of the pod base coordinate system is the same as that of the inertial coordinate system. Its X-axis points to the head of the drone and is parallel to the drone's roll axis. Its Z-axis points to the bottom of the drone and is parallel to the drone's heading axis. The Y-axis can be obtained by the right-hand rule and points to the right wing of the drone.

[0039] The origin of the line-of-sight coordinate system is the intersection of the sensing axes of the inertial measurement unit inside the pod. When both the pitch and roll frames are at zero, the three axes of the line-of-sight coordinate system coincide with the coordinate system of the pod base, with the line-of-sight direction being Z. S .

[0040] In summary, this technical solution specifically discloses a target search control command planning method for an unmanned aerial vehicle (UAV) pod, including the following steps: First, a coordinate system is preset, comprising an Earth coordinate system, an inertial coordinate system, a pod base coordinate system, and a line-of-sight coordinate system. Then, the information acquisition module in the UAV collects first, second, and third operational information and the slant distance from the imager along the line of sight to the ground through the UAV's navigation, facilitating the subsequent generation of UAV pod target search control commands using this information.

[0041] To make the target search control commands of the UAV pod more accurate, and to isolate the disturbances of the carrier aircraft from the command planning, this application calculates the compensated angular velocity by using the first component and the slant distance from the imager along the line of sight to the ground. This makes the final target search commands more accurate, effectively solving the problem of image blurring during the search process, and also avoiding the phenomenon of missing ground objects. In addition, the information acquisition module of this application also has a data update command that can update the acquired data in real time, ensuring the timeliness of the acquired data. Attached Figure Description

[0042] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0043] Figure 1 This is a flowchart illustrating a target search control command planning method for an unmanned aerial vehicle (UAV) pod.

[0044] Figure 2 A flowchart illustrating the search command planning process for a target search control command planning method for an unmanned aerial vehicle (UAV) pod.

[0045] Figure 3This is a schematic diagram of the "line" search instruction planning in a target search control instruction planning method for an unmanned aerial vehicle (UAV) pod.

[0046] Figure 4 This is a schematic diagram of target search imaging for a target search control command planning method for an unmanned aerial vehicle (UAV) pod. Detailed Implementation

[0047] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0048] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0049] Example 1

[0050] Please refer to Figure 1 The flowchart shown here illustrates a target search control command planning method for an unmanned aerial vehicle (UAV) pod provided in this application, including the following steps:

[0051] A preset coordinate system is used, which includes the Earth coordinate system, the inertial coordinate system, the pod base coordinate system, and the line-of-sight coordinate system. The preset coordinate system enables the flight information of the UAV to be decomposed into components in each system during flight, which facilitates the decomposition, calculation and planning of the angular velocity of the UAV during flight.

[0052] This application includes three modules: an information acquisition module, a line search planning module, and a control instruction calculation module.

[0053] The detailed functions of the information collection module are as follows:

[0054] The first operational information of the UAV pod is collected, including the UAV's roll, pitch, and yaw attitude angles, as well as the UAV's north velocity (v). n Dongsu V e and vertical velocity v v The three linear velocities, all of which were acquired by the pose measurement module in the UAV pod, are used for the calculation of subsequent control speed commands.

[0055] The second operational information of the UAV pod is collected, including the roll angular velocity and pitch angular velocity of the imager's line of sight. The above data is collected by the inertial angular velocity sensor measurement module of the UAV pod.

[0056] The third operational information of the UAV pod is collected, including the roll angle and pitch angle of the imager's line of sight. This data is acquired by the frame angle measurement module of the UAV pod and can be used in conjunction with the UAV's roll, pitch, and yaw attitude angles to update the transfer matrix from the inertial coordinate system to the line of sight coordinate system in real time.

[0057] The sensors of each acquisition system in the above data acquisition modules are all from inside the pod. Issues such as data refresh rate and synchronous calculation are autonomously controllable, with strong real-time performance, and data accuracy can be guaranteed through appropriate selection.

[0058] Obtain the slant distance r of the imager along the line of sight to the ground. l slant distance r l The data was collected by the ranging device inside the UAV pod and used for subsequent calculation of the compensation angular velocity.

[0059] like Figure 3 As shown, the detailed functions of the row search planning module are as follows:

[0060] Set the planning speed for the "line" search command. The planning speed for the line search command is planned in the form of an offset trigonometric function. This is used to achieve step-by-step staring with the angular position of the visual axis on the basis of inertial stability.

[0061] The detailed functions of the row search planning module are as follows:

[0062] Obtain the angular velocity of the "row" scan plan, which is calculated based on the planning velocity of the "row" search command;

[0063] The detailed functions of the control command calculation module are as follows:

[0064] The first component of the UAV's velocity relative to the Earth in the line-of-sight coordinate system is obtained. The first component is calculated from the first operational information and the second operational information. The first component is the component of the UAV's velocity relative to the Earth in the line-of-sight coordinate system.

[0065] The compensation angular velocity required for the aircraft to fly along the Earth's surface is calculated by the first component and the slant distance r from the imager along the line of sight to the ground. l The calculation shows that the compensation angular velocity is the amount of interference that needs to be isolated from the drone in addition to achieving the specified motion during the planning process.

[0066] Generate target search control commands for the UAV pod and input them to the servo control terminal. The target search commands are calculated from the "line" scan planning angular velocity and the compensation angular velocity, where, according to equation (7) The decomposition provides the "line" search plan for the region where the line of sight points to the ground, from which the servo control speed command plan in relative inertial space can be obtained.

[0067] like Figure 2 As shown, it also includes generating a data update instruction, which is used to update the first operating information, the second operating information, and the third operating information in real time; generating the data update instruction includes the following steps:

[0068] Obtain the first transition matrix First transition matrix The first transfer matrix was acquired by the frame angle measurement module of the UAV pod. This is the transition matrix from the pod base coordinate system to the line-of-sight coordinate system;

[0069] Obtain the second transition matrix The second transition matrix Acquired by the pose measurement module; the second transition matrix This is the transition matrix from the inertial coordinate system to the pod base coordinate system;

[0070] Production data update instruction, the data update instruction being derived from the first transition matrix. Second transition matrix Calculated according to equation (4); during the UAV scanning process, it can be seen from the transformation according to equation (6) that the two frame angles of the pod (roll angular velocity and pitch angular velocity of the imager's line of sight) and the three attitude angles of the UAV (including the UAV's roll, pitch and yaw attitude angles) can be updated in real time through the information acquisition module, thereby updating the transfer matrix from the inertial coordinate system to the line of sight coordinate system in real time. This method can effectively avoid the error caused by directly integrating the rate;

[0071] like Figure 3 As shown, specifically, the angular velocity of the "row" scan planning is calculated using the following formula:

[0072]

[0073]

[0074] (1) is calculated from (2), where A is the required "line" search angle of the pod perpendicular to the track direction; L is the depth length of the imager on the ground along the track direction; V is the flight speed of the UAV in the search operation state; all the above data are provided by the mission background requirements. ω represents the component of the infrared detector's angular velocity vector in the Earth coordinate system within the detector's line-of-sight coordinate system. S Plan the speed for the "line" search command.

[0075] Specifically, the first component is calculated according to the following formula:

[0076]

[0077]

[0078] Among them, [v1 v2 v3] T Let v be the first component of the drone's velocity relative to the Earth in the line-of-sight coordinate system; n For the North Speed ​​of Unmanned Aerial Vehicles; v e For the Dongsu drone; v v For the vertical speed of the drone; The first transfer matrix is ​​determined by the roll angle and pitch angle of the imager's line of sight; The second matrix is ​​determined by the UAV's roll attitude angle, pitch attitude angle, and yaw attitude angle. This is the transition matrix from the inertial coordinate system to the line-of-sight coordinate system, which is the basis for data update commands.

[0079] Specifically, the compensation angular velocity is calculated using the following formula:

[0080]

[0081] in, To compensate for the angular velocity, which is the amount of interference the UAV needs to overcome, this interference is caused by the translation of the pod-base coordinate system in the Earth coordinate system due to the UAV's flight motion, resulting in an angular velocity relative to the ground target area; r l This is the slant distance from the imager along the line of sight to the ground.

[0082] Specifically, the target search control commands for the UAV pod are calculated according to the following formula:

[0083]

[0084]

[0085] (6) is calculated from (7), where, The target search control speed command for the UAV pod is given by equation (6). The input signal of the servo control speed loop is relative to the inertial space. Therefore, the "line" search planning command given by equation (6) pointing to the ground area needs to be converted into the servo control speed command planning in the relative inertial space.

[0086] Specifically, the coordinate system is set according to the following rules:

[0087] The origin of the Earth coordinate system is at the geometric center of the Earth. Its X-axis points to the intersection of the 0-degree longitude and 0-degree latitude, the Z-axis points north through the polar axis, and the Y-axis is obtained by the right-hand rule.

[0088] The origin of the inertial coordinate system is within the navigation system, and its X-axis points to true north; Z... N The axis points to the earth, X N With Z N Vertical, Y N Determined by the right-hand rule;

[0089] The origin of the pod base coordinate system is the same as that of the inertial coordinate system. Its X-axis points towards the head of the drone and is parallel to the drone's roll axis. Its Z-axis points towards the bottom of the drone and is parallel to the drone's heading axis. The Y-axis can be obtained by the right-hand rule and points towards the right wing of the drone.

[0090] The origin of the line-of-sight coordinate system is the intersection of the sensing axes of the inertial measurement unit inside the pod. When both the pitch and roll frames are at zero, the three axes of the line-of-sight coordinate system coincide with the coordinate system of the pod base, with the line-of-sight direction being Z. S .

[0091] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A method for planning target search control commands for an unmanned aerial vehicle (UAV) pod, characterized in that, The target search control instruction planning method includes the following steps: A predefined coordinate system is defined, comprising an Earth coordinate system, an inertial coordinate system, a pod base coordinate system, and a line-of-sight coordinate system. The first operational information of the UAV pod is collected by the attitude measurement module in the UAV pod; the first operational information includes the UAV roll, pitch and yaw attitude angles and the UAV's north speed, east speed and vertical speed. The second operational information of the UAV pod is collected by the inertial angular velocity sensor measurement module in the UAV pod; the second operational information includes the roll angular velocity and pitch angular velocity of the imager's line of sight. The third operational information of the UAV pod is collected by the UAV pod frame angle measurement module; the third operational information includes the roll angle and pitch angle of the imager's line of sight. The slant distance from the imager along the line of sight to the ground is obtained, and the slant distance is collected by the ranging device inside the UAV pod; Set the planning speed for the "row" search instruction, and the planning speed for the "row" search instruction is planned using the form of an offset trigonometric function; The angular velocity of the "row" scan planning is obtained, which is calculated based on the planning velocity of the "row" search instruction; The first component of the UAV's velocity relative to the Earth in the line-of-sight coordinate system is obtained, and the first component is calculated from the first operational information and the second operational information. The compensation angular velocity required for the UAV to fly along the Earth's surface is calculated, and the compensation angular velocity is obtained by the first component and the slant distance from the imager along the line of sight to the ground; Generate a target search control speed command for the UAV pod and input it to the servo control terminal. The target search control speed command is calculated from the "line" scan planning angular velocity and the compensation angular velocity.

2. The target search control command planning method for an unmanned aerial vehicle (UAV) pod according to claim 1, characterized in that, It also includes generating data update instructions, which are used to update the first operating information, the second operating information, and the third operating information in real time; generating the data update instructions includes the following steps: Obtain the first transfer matrix, which is acquired by the frame angle measurement module of the UAV pod; the first transfer matrix is ​​the transfer matrix from the pod base coordinate system to the line-of-sight coordinate system; Obtain the second transition matrix, which is acquired by the pose measurement module; The second transfer matrix is ​​the transfer matrix from the inertial coordinate system to the pod base coordinate system; A data update instruction is generated, which is calculated from the first transition matrix and the second transition matrix.

3. The target search control command planning method for an unmanned aerial vehicle (UAV) pod according to claim 1, characterized in that, The angular velocity of the "row" scan planning is calculated according to the following formula: Where A is the required "line" search angle of the pod perpendicular to the flight path; L is the depth of the imager's imaging on the ground along the flight path; and V is the UAV's flight speed during the search operation. This represents the component of the infrared detector's angular velocity vector in the Earth coordinate system within the detector's line-of-sight coordinate system. Plan the speed for the "line" search command.

4. The target search control command planning method for an unmanned aerial vehicle (UAV) pod according to claim 3, characterized in that, The first component is calculated according to the following formula: （3） （4） Among them, [v1v2v3] T Let v be the first component of the drone's velocity relative to the Earth in the line-of-sight coordinate system; n For the North Speed ​​of Unmanned Aerial Vehicles; v e For the Dongsu drone; v v For the vertical speed of the drone; The first transfer matrix is ​​determined by the roll angle and pitch angle of the imager's line of sight; The second matrix is ​​determined by the UAV's roll attitude angle, pitch attitude angle, and yaw attitude angle. This is the transition matrix from the inertial coordinate system to the line-of-sight coordinate system, which is the basis for data update commands.

5. The target search control command planning method for an unmanned aerial vehicle (UAV) pod according to claim 4, characterized in that, The compensated angular velocity is calculated according to the following formula: in, To compensate for angular velocity; rl This is the slant distance from the imager along the line of sight to the ground.

6. The target search control command planning method for an unmanned aerial vehicle (UAV) pod according to claim 5, characterized in that, The target search and control commands for the UAV pod are calculated according to the following formula: in, Provides speed control commands for target search on the UAV pod.

7. The target search control command planning method for an unmanned aerial vehicle (UAV) pod according to claim 1, characterized in that, The coordinate system is set according to the following rules: The origin of the Earth coordinate system is at the geometric center of the Earth. Its X-axis points to the intersection of the 0-degree longitude and 0-degree latitude, the Z-axis points north through the polar axis, and the Y-axis is obtained by the right-hand rule. The origin of the inertial coordinate system is within the navigation system, with its X-axis pointing due north; the ZN axis points to the ground, XN is perpendicular to ZN, and YN is determined by the right-hand rule. The origin of the pod base coordinate system is the same as that of the inertial coordinate system. Its X-axis points to the head of the drone and is parallel to the drone's roll axis. Its Z-axis points to the bottom of the drone and is parallel to the drone's heading axis. Its Y-axis is obtained by the right-hand rule and points to the right wing of the drone. The origin of the line-of-sight coordinate system is the intersection of the sensitive axes of the inertial measurement unit inside the UAV pod. When both the pitch frame and the roll frame are at zero, the three axes of the line-of-sight coordinate system coincide with the coordinate system of the pod base, and the line-of-sight direction is ZS.

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