Unmanned aerial vehicle monocular axis-shifting vision imaging calibration method

Abstract

The present application relates to the technical field of unmanned aerial vehicle monocular moving axis vision imaging, and particularly relates to a method for calibrating unmanned aerial vehicle monocular moving axis vision imaging, comprising the following steps: determining a measurement target, and determining measurement parameters according to the measurement target; establishing a moving axis camera imaging model, and obtaining initial moving axis camera imaging parameters based on the measurement parameters; establishing a moving axis camera imaging optimization model, and determining optimal moving axis camera imaging parameters; configuring the moving axis camera based on the optimal moving axis camera imaging parameters and determining a take-off position of the unmanned aerial vehicle; and after the unmanned aerial vehicle takes off, adjusting the unmanned aerial vehicle to align the moving axis camera with the measurement target, so that clear imaging of all the measurement targets can be achieved. Through the moving axis camera imaging model and the moving axis camera imaging optimization model, accurate moving axis camera imaging parameters are obtained according to known measurement parameters, clear imaging of the unmanned aerial vehicle monocular moving axis camera is ensured, and technical support is provided for high-precision multi-point measurement in engineering monitoring.

Description

Technical Field

[0001] This invention relates to the field of monocular tilt-shift vision imaging technology for unmanned aerial vehicles (UAVs), and more specifically to a method for calibrating monocular tilt-shift vision imaging for UAVs. Background Technology

[0002] In recent years, with the rapid development of tilt-shift vision technology, it has been widely applied in various fields. For example, in the medical field, this technology is used in corneal measurement, cataract surgery, particle image velocimetry, line structured light, and laser triangulation. In deformation monitoring, tilt-shift vision technology for multi-point measurement of bridges has achieved full-span displacement monitoring. Furthermore, combined with stereo digital image correlation technology, tilt-shift cameras have been successfully applied to full-field three-dimensional deformation measurement. Tilt-shift vision technology has opened up new possibilities for multi-point displacement measurement of engineering structures, demonstrating significant advantages, especially in the monitoring of complex engineering structures with large depths.

[0003] However, combining tilt-shift cameras with UAV technology to form a UAV tilt-shift camera monitoring system for high-precision monitoring of multi-point displacement in engineering structures still faces many challenges. Ensuring clear imaging from the airborne tilt-shift camera is one of the key difficulties. Currently, most tilt-shift cameras are mainly used on ground platforms, and their imaging parameters can be optimized through manual adjustment. However, the function of automatically adjusting tilt-shift camera parameters on UAV platforms is not yet mature, and multiple flight tests are usually required to determine the optimal configuration. This not only reduces operational efficiency but also increases technical complexity. Therefore, researching a UAV monocular tilt-shift vision imaging calibration method to pre-calibrate the tilt-shift camera imaging parameters to ensure clear imaging of measurement points along the bridge structure is of significant research importance and practical application value in solving the above problems. Summary of the Invention

[0004] The purpose of this invention is to provide a monocular tilt-shift vision imaging calibration method for unmanned aerial vehicles (UAVs) to solve the technical problems existing in the prior art. The specific technical solution is as follows:

[0005] The method for calibrating monocular tilt-shift vision imaging in unmanned aerial vehicles includes the following steps:

[0006] S1. Determine the measurement target and determine the measurement parameters based on the measurement target;

[0007] S2. Establish a tilt-shift camera imaging model and obtain initial tilt-shift camera imaging parameters based on the measurement parameters;

[0008] S3. Establish an imaging optimization model for the tilt-shift camera and determine the optimal imaging parameters for the tilt-shift camera;

[0009] S4. Configure the tilt-shift camera based on the optimal tilt-shift camera imaging parameters and determine the take-off position of the UAV; after the UAV takes off, adjust the UAV so that the tilt-shift camera is aligned with the measurement target, and all measurement targets can be clearly imaged.

[0010] Furthermore, in S1, the measurement parameters include the measurement range S on the focal plane. t The distance D from the projection point of the optical center of the tilt-shift camera lens onto the focal plane to the edge of the measurement range. t .

[0011] Furthermore, in S2, the tilt-shift camera imaging model is as follows:

[0012] D h =(S+D l tan(β-θ)=D l tanβ;

[0013] D s =D l / cos(θ+γ)=D h / sin(θ+γ);

[0014]

[0015]

[0016]

[0017] In the above formula, α is the tilt-shift angle, f is the focal length of the tilt-shift camera lens, J represents the distance from the optical center of the tilt-shift camera lens to the hinge line, d represents the distance from the hinge line to the edge of the field of view, θ is the field of view angle of the tilt-shift camera lens, and D... l And S are field of view parameters, where S is the field of view range on the focal plane, and D is the focal plane range. l D is the distance from the projection point of the optical center of the tilt-shift camera lens onto the focal plane to the edge of the field of view. s D is the straight-line distance from the optical center of a tilt-shift camera lens to the edge of its field of view. h Let be the vertical distance from the optical center of the tilt-shift camera lens to the focal plane, and β and γ be the angles between the line connecting the optical center of the tilt-shift camera lens to the edge of the field of view and the focal plane. According to the above formula, in the field of view parameter D... l Given S, the imaging parameters D of the tilt-shift camera can be solved. h And α.

[0018] Furthermore, the initial tilt-shift camera imaging parameters obtained based on the measurement parameters are as follows:

[0019] The measurement parameter D in S1 t With S t As the field of view parameter D lThe initial values ​​of S and D are used to obtain the initial values ​​of the tilt-shift camera imaging parameters through the tilt-shift camera imaging model. h And α.

[0020] Furthermore, the tilt-shift camera imaging optimization model is as follows:

[0021] τ1=π-(π / 2-(β-θ / 2)+α)-(β-θ);

[0022] τ2=π-(π / 2-(β-θ / 2)+α)-β;

[0023] |ON|=f / sin(τ1);

[0024] |OP|=f / sin(τ2);

[0025]

[0026]

[0027] ∠MON=arcsin(|MN|sinτ1 / |OM|);

[0028] ∠POQ=arcsin(|PQ|sinτ2 / |OQ|);

[0029] β1 = β - (θ - ∠MON);

[0030] β2=β-∠POQ;

[0031] D t =D h / tan(β2);

[0032] S t =D h / tan(β1)-D t ;

[0033] In the above formula, S t D represents the measurement range on the focal plane. t α represents the distance from the projection point of the optical center of the tilt-shift camera lens onto the focal plane to the edge of the measurement range. β and γ are the angles between the line connecting the optical center of the tilt-shift camera lens to the edge of the field of view and the focal plane. β1 and β2 represent the angles between the line connecting the optical center of the tilt-shift camera lens to the edge of the measurement range and the focal plane. τ1 and τ2 represent the angles between the reverse extension of the line connecting the optical center of the tilt-shift camera lens to the edge of the field of view and the image plane. MN and PQ are the reserved pixel areas on the left and right sides of the image plane.

[0034] Furthermore, the specific steps for determining the optimal tilt-shift camera imaging parameters include:

[0035] S3.1 Initial values ​​D of the tilt-shift camera imaging parameters obtained in S2 h And α, along with the tilt-shift camera imaging optimization model, calculate the new measurement parameter D. t and S t ;

[0036] S3.2 Determine the new measurement parameter D t and S t With the initial measurement parameter D t and S t If the phase difference is less than a set threshold, then the corresponding tilt-shift camera imaging parameter D is determined. h α and α are the optimal imaging parameters for the tilt-shift camera; if they are not less than the set threshold, proceed to step S3.3;

[0037] S3.3, Reduce the field of view parameter D l The initial value of the field of view parameter S is increased, and the new tilt-shift camera imaging parameters are calculated based on the tilt-shift camera imaging model.

[0038] S3.4. Based on the tilt-shift camera imaging parameters obtained in S3.3 and the tilt-shift camera imaging optimization model, calculate the new measurement parameter D. t and S t ;

[0039] S3.5 Repeat steps S3.2 to S3.4 until the set conditions are met.

[0040] Furthermore, the specific steps of S4 are as follows:

[0041] Based on the optimal tilt-shift camera imaging parameters obtained in S3, adjust the focusing ring of the UAV tilt-shift camera to make it focus at a distance D. s2 The target being measured is clearly focused, where D s2 This is the straight-line distance from the optical center of the tilt-shift camera lens to the edge of the measurement range;

[0042] Adjust the tilt-shift angle of the tilt-shift camera to α, based on the vertical distance D from the optical center of the tilt-shift camera lens to the focal plane. h The distance D from the projection point of the optical center of the tilt-shift camera lens onto the focal plane to the edge of the measurement range. t First, determine the takeoff position of the drone; after the drone takes off, adjust the drone so that the tilt-shift camera is aligned with the measurement target, and all measurement targets can be clearly imaged.

[0043] The application of the technical solution of the present invention has the following beneficial effects:

[0044] The UAV monocular tilt-shift vision imaging calibration method proposed in this invention obtains accurate tilt-shift camera imaging parameters based on known measurement parameters through a tilt-shift camera imaging model and a tilt-shift camera imaging optimization model, ensuring that the UAV monocular tilt-shift camera achieves clear imaging and providing technical support for high-precision multi-point measurement in engineering monitoring.

[0045] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0046] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0047] Figure 1 This is a flowchart of the UAV monocular tilt-shift vision imaging calibration method of the present invention;

[0048] Figure 2 This is a diagram of the tilt-shift camera imaging model established in the embodiments of the present invention;

[0049] Figure 3 This is a diagram of the tilt-shift camera imaging optimization model established in the embodiments of the present invention;

[0050] Figure 4 yes Figure 3 Local magnification Figure 1 ;

[0051] Figure 5 yes Figure 3 Local magnification Figure 2 ;

[0052] Figure 6 This is an experimental scene diagram of the tilt-shift camera imaging optimization model;

[0053] Figure 7 These are experimental results of the tilt-shift camera imaging optimization model, where (a) is the result without adjusting the tilt-shift angle, and (b) is the result after adjusting the tilt-shift angle.

[0054] Figure 8 This is an experimental scene diagram of the UAV monocular tilt-shift vision imaging calibration method of the present invention;

[0055] Figure 9 This is an experimental result diagram of the UAV monocular axis-shifting vision imaging calibration method of the present invention. Detailed Implementation

[0056] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered.

[0057] In the description of this invention, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", "front", "back", "lateral", "longitudinal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to 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.

[0058] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0059] Example:

[0060] See Figure 1 This invention provides a method for calibrating monocular tilt-shift vision imaging in unmanned aerial vehicles (UAVs), comprising the following steps:

[0061] S1. Determine the measurement target and determine the measurement parameters based on the measurement target;

[0062] S2. Establish a tilt-shift camera imaging model and obtain initial tilt-shift camera imaging parameters based on the measurement parameters;

[0063] S3. Establish an imaging optimization model for the tilt-shift camera and determine the optimal imaging parameters for the tilt-shift camera;

[0064] S4. Configure the tilt-shift camera based on the optimal tilt-shift camera imaging parameters and determine the take-off position of the UAV; after the UAV takes off, adjust the UAV so that the tilt-shift camera is aligned with the measurement target, and all measurement targets can be clearly imaged.

[0065] In S1, based on the determined measurement target, the measurement parameters are determined using the UAV monocular tilt-shift camera. These measurement parameters include the measurement range S on the focal plane. t The distance D from the projection point of the optical center of the tilt-shift camera lens onto the focal plane to the edge of the measurement range. t .

[0066] In S2, see Figure 2 The tilt-shift camera imaging model is as follows:

[0067] D h =(S+D l tan(β-θ)=D l tanβ (Formula 1);

[0068] D s =D l / cos(θ+γ)=D h / sin(θ+γ) Equation 2);

[0069]

[0070]

[0071]

[0072] In the above formula, α is the tilt-shift angle, f is the focal length of the tilt-shift camera lens, J represents the distance from the optical center of the tilt-shift camera lens to the hinge line, d represents the distance from the hinge line to the edge of the field of view, θ is the field of view angle of the tilt-shift camera lens, and D... l And S are field of view parameters, where S is the field of view range on the focal plane, and D is the focal plane range. l D is the distance from the projection point of the optical center of the tilt-shift camera lens onto the focal plane to the edge of the field of view. s D is the straight-line distance from the optical center of a tilt-shift camera lens to the edge of its field of view. h Let be the vertical distance from the optical center of the tilt-shift camera lens to the focal plane, and β and γ be the angles between the line connecting the optical center of the tilt-shift camera lens to the edge of the field of view and the focal plane. According to the above formula, in the field of view parameter D... l Given S, the imaging parameters D of the tilt-shift camera can be solved. h And α.

[0073] The measurement parameter D in S1 t With S t As the field of view parameter D l The initial values ​​of S and D are used to obtain the initial values ​​of the tilt-shift camera imaging parameters through the tilt-shift camera imaging model. h And α.

[0074] In S3, see Figures 3-5 To ensure that the target does not jump out of the field of view, space needs to be reserved on both sides of the image when calculating the imaging parameters of the tilt-shift camera (i.e., Figure 5 The lengths of PQ and MN are determined, and an imaging optimization model for the tilt-shift camera is established. The tilt-shift camera imaging optimization model is specifically as follows:

[0075] τ1=π-(π / 2-(β-θ / 2)+α)-(β-θ) Formula 6);

[0076] τ2=π-(π / 2-(β-θ / 2)+α)-β Formula 7);

[0077] |ON|=f / sin(τ1) Equation 8);

[0078] |OP|=f / sin(τ2) Equation 9);

[0079]

[0080]

[0081] ∠MON=arcsin(|MN|sinτ1 / |OM|) Equation 12);

[0082] ∠POQ=arcsin(|PQ|sinτ2 / |OQ|) Equation 13);

[0083] β1=β-(θ-∠MON) (Equation 14);

[0084] β2=β-∠POQ (Equation 15);

[0085] D t =D h / tan(β2) Equation 16);

[0086] S t =D h / tan(β1)-D t Equation 17);

[0087] In the above formula, S t D represents the measurement range on the focal plane. t α represents the distance from the projection point of the optical center of the tilt-shift camera lens onto the focal plane to the edge of the measurement range. β and γ are the angles between the line connecting the optical center of the tilt-shift camera lens to the edge of the field of view and the focal plane. β1 and β2 are the angles between the line connecting the optical center of the tilt-shift camera lens to the edge of the measurement range and the focal plane. τ1 and τ2 are the angles between the reverse extension of the line connecting the optical center of the tilt-shift camera lens to the edge of the field of view and the image plane. MN and PQ are the reserved pixel areas on the left and right sides of the image plane (used to ensure that the measurement target is always within the effective field of view when the measurement target or camera moves within the allowable range), avoiding the loss of the measurement target in the field of view due to drone shaking.

[0088] The specific steps for determining the optimal imaging parameters for a tilt-shift camera include:

[0089] S3.1 Initial values ​​D of the tilt-shift camera imaging parameters obtained in S2 h And α, along with the tilt-shift camera imaging optimization model, calculate the new measurement parameter D. t and S t ;

[0090] S3.2 Determine the new measurement parameter D t and S t With the initial measurement parameter D t and S tIf the phase difference is less than a set threshold, then the corresponding tilt-shift camera imaging parameter D is determined. h α and α are the optimal imaging parameters for the tilt-shift camera; if they are not less than the set threshold, proceed to step S3.3;

[0091] S3.3 In this embodiment, the field of view parameter D is reduced in increments of 10mm. l The initial value of the field of view parameter S is increased, and the new tilt-shift camera imaging parameters are calculated based on the tilt-shift camera imaging model.

[0092] S3.4. Based on the tilt-shift camera imaging parameters obtained in S3.3 and the tilt-shift camera imaging optimization model, calculate the new measurement parameter D. t and S t ;

[0093] S3.5 Repeat steps S3.2 to S3.4 until the set conditions are met.

[0094] The specific steps of S4 are as follows:

[0095] Based on the optimal tilt-shift camera imaging parameters obtained in S3, adjust the focusing ring of the UAV tilt-shift camera to make it focus at a distance D. s2 The target being measured is clearly focused, where D s2 This is the straight-line distance from the optical center of the tilt-shift camera lens to the edge of the measurement range;

[0096] Adjust the tilt-shift angle of the tilt-shift camera to α, based on the vertical distance D from the optical center of the tilt-shift camera lens to the focal plane. h The distance D from the projection point of the optical center of the tilt-shift camera lens onto the focal plane to the edge of the measurement range. t First, determine the takeoff position of the drone; after the drone takes off, adjust the drone so that the tilt-shift camera is aligned with the measurement target, and all measurement targets can be clearly imaged.

[0097] The UAV monocular tilt-shift vision imaging calibration method proposed in this invention obtains accurate tilt-shift camera imaging parameters based on known measurement parameters through a tilt-shift camera imaging model and a tilt-shift camera imaging optimization model, ensuring that the UAV monocular tilt-shift camera achieves clear imaging and providing technical support for high-precision multi-point measurement in engineering monitoring.

[0098] (1) Validation experiment of the imaging optimization model of the tilt-shift camera

[0099] To verify the accuracy of the tilt-shift camera imaging optimization model, a verification experiment was conducted. The equipment and parameters used in the experiment are shown in Table 1.

[0100] Table 1. Experimental Equipment and Parameters for Verification of the Tilt-Shift Camera Imaging Optimization Model

[0101]

[0102] Set measurement range S t The distance D from the projection point of the optical center of the tilt-shift camera lens onto the focal plane to the edge of the measurement range is 2.4 meters. t It is 4.2 meters, such as Figure 6 As shown; the lengths of MN and PQ are set to 240 pixels, meaning that 240 pixels of space are left on each side of the image. According to equations 1)-17), the tilt-shift angle α is calculated to be 5.6°, and D... h The value is 1.0 meter; the tilt-shift angle is adjusted using an angle slide table, and the result is as follows. Figure 7 As shown. Among them, Figure 7 Image (a) shows the image when the axis shift angle α is 0°. It can be seen that only measurement marks 104 and 044 are clear. Figure 7 Image (b) in the figure represents the image when the tilt-shift angle is 5.6°. It can be seen that all the measurement marks in image (b) are clear, which verifies the accuracy of the tilt-shift camera imaging optimization model.

[0103] (2) Verification experiment of UAV monocular tilt-shift vision imaging calibration method

[0104] To verify the accuracy of the UAV tilt-shift vision imaging calibration method, a verification experiment was conducted. The equipment and parameters used in the experiment are shown in Table 2.

[0105] Table 2. Experimental Equipment and Parameters for Verification of UAV Monocular Axis-Shift Visual Imaging Calibration Method

[0106]

[0107]

[0108] Set measurement range S t The distance D from the projection point of the optical center of the tilt-shift camera lens onto the focal plane to the edge of the measurement range is 28 meters. t It is 15 meters, such as Figure 8 As shown; the lengths of MN and PQ are set to 320 pixels, meaning 320 pixels of space are left on each side of the image; according to equations 1)-17), the calculated tilt-shift angle is 2.4°, D h It is 2.1 meters, D s2 It is 15.1 meters Subsequently, the tilt-shift camera was set to a tilt-shift angle of 2.4°, and the lens focusing ring was adjusted to achieve clear focus on the measurement target at a distance of 15.1 meters. Then, based on parameter D... t With D h Determine the takeoff location of the drone.

[0109] Images of the measurement markers collected after the drone took off, such as Figure 9 As shown. According to Figure 9 It can be seen that all measurement marks T1-T5 can be clearly imaged, which verifies the effectiveness of the UAV monocular tilt-shift vision imaging calibration method.

[0110] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for calibrating monocular tilt-shift vision imaging in unmanned aerial vehicles (UAVs), characterized in that, Includes the following steps: S1. Determine the measurement target and determine the measurement parameters based on the measurement target; S2. Establish a tilt-shift camera imaging model and obtain initial tilt-shift camera imaging parameters based on the measurement parameters; The tilt-shift camera imaging model is as follows: ； ； ； ； ； In the above formula, For the axis shift angle, For the focal length of a tilt-shift camera lens, This represents the distance from the optical center of the tilt-shift camera lens to the hinge line. This indicates the distance from the hinge line to the edge of the field of view. This refers to the field of view angle of a tilt-shift camera lens. and S For field of view parameters, S The field of view on the focal plane. This is the distance from the projection point of the optical center of the tilt-shift camera lens onto the focal plane to the edge of the field of view. This is the straight-line distance from the optical center of the tilt-shift camera lens to the edge of the field of view. The vertical distance from the optical center of the tilt-shift camera lens to the focusing plane. and The angle between the line connecting the optical center of the tilt-shift camera lens to the edge of the field of view and the focusing plane; S3. Establish an imaging optimization model for the tilt-shift camera and determine the optimal imaging parameters for the tilt-shift camera; The tilt-shift camera imaging optimization model is specifically as follows: ； ； ； ； ； ； ； ； ； ； ； ； In the above formula, The measurement range on the focal plane. This represents the distance from the projection point of the optical center of the tilt-shift camera lens onto the focal plane to the edge of the measurement area. and The angle between the line connecting the optical center of the tilt-shift camera lens to the edge of the field of view and the focal plane. and This represents the angle between the line connecting the optical center of the tilt-shift camera lens to the edge of the measurement range and the focal plane. and This represents the angle between the backward extension of the line connecting the optical center of the tilt-shift camera lens to the edge of the field of view and the image plane. , Pixel areas reserved on the left and right sides of the image plane; S4. Configure the tilt-shift camera based on the optimal tilt-shift camera imaging parameters and determine the take-off position of the UAV; after the UAV takes off, adjust the UAV so that the tilt-shift camera is aligned with the measurement target, and all measurement targets can be clearly imaged.

2. The UAV monocular tilt-shift vision imaging calibration method according to claim 1, characterized in that, In S1, the measurement parameters include the measurement range on the focal plane. The distance from the projection point of the optical center of the tilt-shift camera lens onto the focal plane to the edge of the measurement range. .

3. The UAV monocular tilt-shift vision imaging calibration method according to claim 1, characterized in that, The initial tilt-shift camera imaging parameters obtained based on the measurement parameters are as follows: The measurement parameters in S1 and As a field of view parameter and S The initial values ​​are obtained by using the tilt-shift camera imaging model to obtain the initial values ​​of the tilt-shift camera imaging parameters. and .

4. The UAV monocular tilt-shift vision imaging calibration method according to claim 3, characterized in that, The specific steps for determining the optimal imaging parameters for a tilt-shift camera include: S3.1 Initial values ​​of the tilt-shift camera imaging parameters obtained in S2 and And a tilt-shift camera imaging optimization model to calculate new measurement parameters. and ; S3.2 Determine the new measurement parameters and Compared with the initial measurement parameters and If the phase difference is less than a set threshold, then the corresponding tilt-shift camera imaging parameters are... and These are the optimal imaging parameters for the tilt-shift camera; if they are not less than the set threshold, proceed to step S3.

3. S3.3, Reduce field of view parameters The initial value, increase the field of view parameter S The initial values ​​are used to calculate new tilt-shift camera imaging parameters based on the tilt-shift camera imaging model; S3.

4. Based on the tilt-shift camera imaging parameters obtained in S3.3 and the tilt-shift camera imaging optimization model, calculate the new measurement parameters. and ; S3.5 Repeat steps S3.2 to S3.4 until the set conditions are met.

5. The UAV monocular tilt-shift vision imaging calibration method according to claim 4, characterized in that, The specific steps of S4 are as follows: Based on the optimal tilt-shift camera imaging parameters obtained from S3, adjust the focusing ring of the UAV tilt-shift camera to achieve the desired focusing distance. The target being measured is clearly focused, among which, This is the straight-line distance from the optical center of the tilt-shift camera lens to the edge of the measurement range; Adjust the tilt-shift angle of the tilt-shift camera to Based on the vertical distance from the optical center of the tilt-shift camera lens to the focal plane The distance from the projection point of the optical center of the tilt-shift camera lens onto the focal plane to the edge of the measurement range. First, determine the takeoff position of the drone; after the drone takes off, adjust the drone so that the tilt-shift camera is aligned with the measurement target, and all measurement targets can be clearly imaged.

Images