Unmanned aerial vehicle performance ground test verification platform and method

Abstract

The invention discloses an unmanned aerial vehicle performance ground test verification platform and method which are used for comprehensive test, ground verification, evaluation and airworthiness judgment of functions and performance parameters of a multi-rotor unmanned aerial vehicle. Through indoor platform testing, one person can operate, large-scale manpower and material resources do not need to be organized to carry out field testing, the testing preparation time is shortened, and the comprehensive cost of manpower, equipment, sites and the like is reduced. The verification platform can be placed in a controllable test environment, the unmanned aerial vehicle is fixed on the verification platform, various complex external scenes such as weather and airspace are accurately simulated, the whole process is controllable, and risks such as unmanned aerial vehicle crash in an external field test are avoided. Finally, high-precision sensors are integrated to collect data, the deflection angle, lift force and operation data of the unmanned aerial vehicle can be captured in real time according to specific working conditions, the accuracy, integrity and timeliness of the data are ensured, and a solid data support is provided for performance deep analysis, algorithm iteration and system optimization.

Description

Technical Field

[0001] This invention belongs to the field of unmanned system testing technology, specifically relating to a ground testing and verification platform and method for the performance of unmanned aerial vehicles (UAVs), used for comprehensive testing, ground verification, evaluation and airworthiness assessment of the functions and performance parameters of multi-rotor UAVs. Background Technology

[0002] With the deep integration and widespread application of drone technology in military, industrial, and civilian fields, the requirements for system complexity, mission reliability, and safety are increasing. However, the current research, development, verification, and airworthiness certification of drones heavily rely on field flight testing. This traditional testing method has many bottlenecks:

[0003] (1) Long testing cycle and high cost: It requires a lot of manpower and resources and a lot of time.

[0004] (2) Uncontrollable environment and high risk: It is greatly affected by external factors such as weather and airspace. Performance boundary testing, fault injection testing and intelligent algorithm verification in complex environments are extremely difficult. Moreover, once a fault occurs, it may cause the drone to crash, resulting in property damage or even casualties.

[0005] (3) Incomplete data acquisition: Field tests make it difficult to accurately and comprehensively collect all dynamic parameters of the UAV under specific working conditions, which limits the in-depth analysis and optimization of its performance.

[0006] Therefore, existing technologies lack a comprehensive indoor testing platform capable of simulating multi-degree-of-freedom motion, synchronously and accurately measuring force and displacement, and integrating data visualization and analysis functions; and before actual field flights, it is necessary to fully verify the necessary flight conditions of the UAV in a safe and controllable indoor environment. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a ground-based testing and verification platform and method for the performance of unmanned aerial vehicles (UAVs). By simulating the flight state of multi-rotor UAVs on the ground and testing parameters such as UAV yaw angle, lift, and motor speed, the functional parameters of multi-rotor UAVs can be verified and evaluated, providing technical support for field flight testing and airworthiness certification.

[0008] To achieve the above objectives, a first aspect of the present invention provides a ground-based testing and verification platform for UAV performance, comprising:

[0009] The upper truncated cone is used to rigidly fix the multi-rotor UAV under test and to make the center of gravity of the UAV coaxial with the rotation center of the upper truncated cone.

[0010] A cross-shaped universal joint is provided between the upper truncated cone and the intermediate rod, giving the upper truncated cone the ability to deflect around the X and Y axes with two degrees of freedom.

[0011] The middle rod is fixed at the upper end to the cross-axis universal joint, and at the lower end is connected to the dynamic force sensor through the dynamic force sensor pressure head. The dynamic force sensor is used to collect the overall lift of the UAV in real time.

[0012] No fewer than three sets of guide rail units, each set of guide rail units including:

[0013] Guide rails and guide rail sliders are used to provide radial translation guidance;

[0014] The grating ruler slide rail and grating ruler slider are used to measure the slider displacement in real time;

[0015] The upper and lower side rods are connected in series with a side rod force sensor to obtain the axial force of the rods;

[0016] The upper ball hinge and the lower ball hinge connect the top of the upper side rod to the upper truncated cone and the bottom of the lower side rod to the slider of the grating ruler, respectively, forming a spatial spherical pair;

[0017] The control and data acquisition system is used to synchronously acquire real-time signals from the dynamic force sensor, side rod force sensor, and grating ruler, and calculate the spatial deflection angle of the upper truncated cone, the overall lift, and the lift distribution of each rotor, thereby completing the performance verification of the UAV in an indoor environment.

[0018] A second aspect of the present invention also provides a ground-based test and verification method for UAV performance, employing the aforementioned platform, comprising the following steps:

[0019] S1: Build a verification platform and model it;

[0020] S2: Fixed installation of the drone; control of the drone with a remote controller; test the drone's deflection angle based on the slider movement distance of the guide rail unit.

[0021] S3: Based on the detection data from the dynamic force sensor and each guide rail unit, calculate the component force perpendicular to the rotor rotation plane, and calculate the resultant force as the overall lift of the UAV;

[0022] S4: Control the UAV in a static state at any angle, and solve for the pitch angle and roll angle based on the overall bank angle and overall yaw angle of the UAV, and further calculate the pitch moment and roll moment; according to the hybrid control logic, select the standardized solution that meets the preset standard from the solution set of motor speeds to obtain the lift of a single motor of the UAV, and further obtain the motor speed;

[0023] S5: Place the verification platform in a controllable test environment and accurately simulate various complex external scenarios to capture the drone's deflection angle, lift, and operation data in real time for specific working conditions.

[0024] Based on the above technical solution, the present invention produces the following beneficial effects:

[0025] (1) Significantly shorten the cycle and reduce costs: Testing is conducted through an indoor platform, which can be operated by a single person. There is no need to organize a large number of manpower and material resources to carry out field testing, which shortens the test preparation time and reduces the overall costs of manpower, equipment and venues.

[0026] (2) Controllable environment and extremely low risk: The verification platform can be placed in a controllable test environment, the drone can be fixed on the verification platform, and various complex external scenarios such as weather and airspace can be accurately simulated. The whole process is controllable, avoiding risks such as drone crashes during field tests.

[0027] (3) Comprehensive and accurate data acquisition to support in-depth optimization: The integrated high-precision sensor data acquisition can capture the UAV's deflection angle, lift and operation data in real time for specific working conditions, ensuring the accuracy, integrity and timeliness of the data, and providing solid data support for in-depth performance analysis, algorithm iteration and system optimization. Attached Figure Description

[0028] Figure 1 This is a structural diagram of a ground-based test and verification platform for UAV performance, as shown in the test example of this application.

[0029] Figure 2 for Figure 1 Exploded view;

[0030] Figure 3 for Figure 1 Top view;

[0031] Figure 4 for Figure 1 Side view;

[0032] Figure 5 According to Figure 1 A schematic diagram of the constructed model;

[0033] Figure 6 This is a flowchart illustrating the working method of a ground-based performance testing and verification platform for unmanned aerial vehicles (UAVs) as described in this application.

[0034] Figure 7 for Figure 5 A schematic diagram showing the upper frustum displaced and deflected in a single direction;

[0035] Figure 8 for Figure 5 A schematic diagram of the plane equation;

[0036] Figure 9 for Figure 5 Planar lift decomposition diagram;

[0037] Figure 10 This is a schematic diagram of the motor distribution of the quadcopter UAV selected for the test example in this application. Detailed Implementation

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] This application first provides a ground-based testing and verification platform for UAV performance, including:

[0040] The lower base is used for overall support and fixation to the ground;

[0041] The upper truncated cone is used to rigidly fix the multi-rotor UAV under test and to make the center of gravity of the UAV coaxial with the rotation center of the upper truncated cone.

[0042] A cross-shaped universal joint is provided between the upper truncated cone and the intermediate rod, giving the upper truncated cone the ability to deflect around the X and Y axes with two degrees of freedom.

[0043] The middle rod is fixed at the upper end to the cross shaft universal joint, and at the lower end is connected to the dynamic force sensor through the dynamic force sensor pressure head. The dynamic force sensor is fixed to the lower base and is used to collect the overall lift of the UAV in real time.

[0044] No fewer than three sets of guide rail units are evenly distributed along the circumference between the lower base and the upper truncated cone. Each set of guide rail units includes:

[0045] The support frame is fixedly connected to the lower base;

[0046] Guide rails and guide rail sliders are used to provide radial translation guidance;

[0047] The grating ruler slide rail and grating ruler slider are used to measure the slider displacement in real time;

[0048] The upper and lower side rods are connected in series with a side rod force sensor to obtain the axial force of the rods;

[0049] The upper ball hinge and the lower ball hinge connect the top of the upper side rod to the upper truncated cone and the bottom of the lower side rod to the slider of the grating ruler, respectively, forming a spatial spherical pair;

[0050] The control and data acquisition system is used to synchronously acquire real-time signals from the dynamic force sensor, side rod force sensor, and grating ruler, and calculate the spatial deflection angle of the upper truncated cone, the overall lift, and the lift distribution of each rotor, thereby completing the performance verification of the UAV in an indoor environment.

[0051] This application also provides a ground-based test and verification method for UAV performance, using the aforementioned platform, including the following steps:

[0052] S1: Build a verification platform and model it;

[0053] S2: Fixed installation of the drone; control of the drone with a remote controller; test the drone's deflection angle based on the slider movement distance of the guide rail unit.

[0054] S3: Based on the detection data from the dynamic force sensor and each guide rail unit, calculate the component force perpendicular to the rotor rotation plane, and calculate the resultant force as the overall lift of the UAV;

[0055] S4: Control the UAV in a static state at any angle, and solve for the pitch angle and roll angle based on the overall bank angle and overall yaw angle of the UAV, and further calculate the pitch moment and roll moment; according to the hybrid control logic, select the standardized solution that meets the preset standard from the solution set of motor speeds to obtain the lift of a single motor of the UAV, and further obtain the motor speed;

[0056] S5: Place the verification platform in a controllable test environment and accurately simulate various complex external scenarios to capture the drone's deflection angle, lift, and operation data in real time for specific working conditions.

[0057] Based on the same concept as the above embodiments, such as Figure 1 , Figure 3 and Figure 4 As shown, this test example uses three guide rails to construct a ground-based test and verification platform for UAV performance, specifically:

[0058] The components include: lower base 1, first guide rail unit 2, second guide rail unit 3, third guide rail unit 4, upper circular platform 5, cross shaft universal joint 6, intermediate rod 7, dynamic force sensor pressure head 8, and dynamic force sensor 9.

[0059] One end of the cross shaft universal joint 6 is connected and fixed to the upper round plate 5 by a thread, and the other end is connected to the intermediate rod 7. The lower end of the intermediate rod 7 is equipped with a dynamic force sensor head 8 by a screw. The head is connected to the dynamic force sensor 9. The dynamic force sensor 9 is finally fixed to the lower base 1 by bolts and nuts, together forming a complete force detection system.

[0060] Furthermore, such as Figure 2 As shown, the first guide rail unit 2 includes: a support frame 21, a guide rail 22, a guide rail slider 23, a connector 24, a grating ruler slider 25, a grating ruler slide rail 26, a lower ball hinge 271, an upper ball hinge 272, a lower side rod 281, an upper side rod 282, and a side rod force sensor 29.

[0061] The lower base 1 and each support frame are made of steel and are connected and fixed by screws to enhance the stability and structural integrity of the overall base.

[0062] It is worth noting that the first guide rail unit 2, the second guide rail unit 3, and the third guide rail unit 4 have the same assembly method and structure. The following is a detailed description of the specific assembly method of the first guide rail unit 2:

[0063] The guide rail 22 is mounted on the support frame 21 and fixed with screws. The guide rail slider 23 is a roller design, paired with the guide rail 22, and can slide freely along the guide rail 22. The upper part of the guide rail slider 23 is connected to the connector 24 by screws to achieve smooth transmission. The grating ruler slide rail 26 is fixed to the support frame 21 by bolts and nuts, using side holes. The grating ruler slider 25 matches the grating ruler slide rail 26 and can slide smoothly. The grating ruler slider 25 is further rigidly connected to the connector 24 by bolts and nuts. The two ends of the side rod force sensor 29 are respectively connected to the lower side rod 281 and the upper side rod 282. The other end of the lower side rod 281 is fixed to the connector 24 by screws using the lower ball hinge 271, and the other end of the upper side rod 282 is also fixed to the upper frustum 5 using the upper ball hinge 272, forming a support structure that can flexibly transmit force.

[0064] Three side force sensors are used to measure tension and compression in their respective directions, while the central dynamic force sensor 9 measures the force in the vertical direction. A grating ruler measures the displacement in the three sub-directions, and the deflection angle of the upper frustum 5 in the three directions can be calculated from the displacement. Then, the three deflection angles are coupled to calculate the deflection angle of the entire upper frustum 5.

[0065] The upper and lower ball joints can both achieve three degrees of freedom of deflection, and the deflection angle is limited to within 45 degrees of the vertical angle with the base; the cross-axis universal joint 6 can achieve two degrees of freedom of deflection.

[0066] like Figure 5 As shown, the overall structure of the above device is modeled. The gray lines represent the overall structural model of the upper frustum in its initial horizontal state, and the black lines represent the overall structural model after the upper frustum has deflected. The centers of the three upper ball hinges are defined as follows: The centers of the three lower ball hinges are respectively , The perpendicular distance to the axis of the intermediate rod is The vertical point is defined as Define a coordinate system in the initial horizontal state of the upper frustum. The origin of the coordinate system is the rotation center of the universal joint 6. Dot, dot Set in the same plane Direction is Positive axis direction shaft edge Rotate the point horizontally counterclockwise by 90 degrees. The positive direction of the axis, the vertical direction is Positive direction of the axis. Let... Length is , All lengths , All lengths . For the centers of each ball in the upper ball hinge after the upper frustum has deflected, The centers of each ball in the lower ball hinge after the upper truncated cone deflects.

[0067] like Figure 6 As shown, based on the above content and the same concept as the methods in the embodiments of this application, the test examples of this application further provide a detailed calculation derivation process, specifically as follows:

[0068] Step 1: Securely mount the drone and control it using the remote controller; test the drone's deflection angle based on the slider movement distance of the guide rail unit. Specifically:

[0069] The drone is fixedly mounted at a predetermined position on the upper circular platform, with its center of gravity aligned with the point... On the same vertical line, the nose points Positive axis direction. Use the remote controller to provide a basic lift to the drone rotor and keep it constant, then use the remote controller to control the drone's pitch and roll.

[0070] Using the model through a single direction To solve for the slope angle in a single direction Taking the first guide rail unit as an example, the moving distance of the guide rail slider is read by the signal output by the grating ruler slider. The It changes dynamically over time. Based on the spatial geometric mapping relationship, the specific calculation method is as follows:

[0071] like Figure 7 As shown, when the drone travels along a straight line Define a straight line when tilting. Deflection to a straight line The slope angle is , can be represented as ,in After the drone deflects, the straight line With a straight line The angle between the points. When the UAV does not yaw (i.e., does not rotate in the vertical direction), point Only It performs translational motion within a plane.

[0072] Connection point With point Let it be used as an auxiliary line segment, and its length be denoted as . .

[0073]

[0074]

[0075]

[0076] Similarly, when the second and third guide rail units move, the corresponding slope angle... for:

[0077]

[0078] On point After the slope angle calculation is completed, define the point. and A straight line connecting points exist Projection on a plane and The angle between the axes is the yaw angle. Based on the calculation results of the slope angle and yaw angle Solving point The equation of the plane in which it is located, and the specific calculation process are as follows:

[0079] like Figure 8 As shown, let point Equation of the plane For any point on this plane Connect the origin With point Form a straight line The straight line and The angle of the plane is denoted as (i.e., slope angle), point exist The projection on the plane is a point. Connect the origin With point Form a straight line The straight line and The angle between the axes is denoted as (i.e., yaw angle). Straight line The direction vector is , and Plane angle satisfy , will point Substituting into the above plane equation, we can obtain ,point Yaw angle satisfy Therefore, in polar coordinates, we have ,in Substituting the above polar coordinates into... We can obtain:

[0080] (5)

[0081] Based on the above reasoning process, the following conclusion can be drawn: For a plane any point on Its slope angle and yaw angle All satisfy the result of equation (5), that is:

[0082] (6)

[0083] Therefore, we can conclude that for a plane Three feature points on Their respective slope angles With yaw angle All satisfy the spatial geometric relationship defined by equation (6), that is: (7)

[0084] Known Direction is Positive direction of axis, straight line The two sides form a 120-degree angle with each other; after the drone deflects, the plane... If the relationship between the points on the line remains unchanged, then the line... They also form a 120-degree angle with each other, point Yaw angle They are respectively Then we can obtain:

[0085] (8)

[0086] Theoretically satisfied .

[0087] From point The relationship between the slope angle and the yaw angle is as follows: (9)

[0088] From point The relationship between the slope angle and the yaw angle is as follows: (10)

[0089] From the above, we can derive the equation of the plane as: (11), or (12).

[0090] Define the plane slope angle as the plane With the horizontal plane (i.e.) The angle between the two planes, i.e., the overall slope angle of the UAV, is denoted as . ; Plane yaw angle is plane The straight line containing the direction of the steepest slope is in Projection on a plane and The included angle of the axis, i.e., the overall yaw angle of the UAV, is denoted as The equation of the plane mentioned above. The normal vector of the plane is .

[0091] The overall slope angle of the drone It can be represented as:

[0092] (13)

[0093] Overall yaw angle of the drone It can be represented as:

[0094] (14)

[0095] Step 2: Test the lift of the drone. Fix the drone in a predetermined position on the upper circular platform, ensuring the rotor plane is parallel to the upper surface of the platform. Use the remote controller to send a lift signal to the drone and control its pitch and roll. Based on this mounting configuration, calculate the component force perpendicular to the rotor plane using data from the dynamic force sensor and the three side stick force sensors, and further determine the overall lift of the drone. The specific calculation method based on spatial geometric mapping is as follows:

[0096] like Figure 9 As shown, the upper frustum and the plane are known. Parallel, with points For example, regarding this point along a plane perpendicular to the plane force (i.e., lift perpendicular to the rotor's plane of rotation), the force detected by the side rod force sensor of the guide rail unit. and plane The correspondence between the deflection angles is calculated. Among them, Dynamically changes over time For the side rod and the plane The angle between the normal vectors can be seen from the figure. Based on this derivation logic, The forces at each of the four points, perpendicular to the rotor's plane of rotation, The relationship between the force detected by the corresponding mechanical sensor and the force detected by the sensor. All satisfy:

[0097] (15)

[0098] in, They are straight lines With plane The angle formed by the normal vectors of .

[0099] Taking the first guide rail unit as an example, when the guide rail slider moves, the moving distance is obtained by reading the signal output by the grating ruler slider. Its dynamic changes over time. It is calculated through spatial geometric mapping. and The mathematical relationship between them, and the specific calculation method, are as follows:

[0100] Given the equation of the plane normal vector Set up points and points Coordinates are ,but The direction vector is:

[0101] The angle between a line and the normal to a plane is calculated using the formula: (17)

[0102] Similarly, in the second and third guide rail units, the extension lines of the lower rods of the second and third guide rail units intersect the plane. Angle formed by normal vectors The corresponding cosine value is: (18)

[0103] The detected forces of the three side rod force sensors and their respective forces The relationship between them is: (19)

[0104] Force on the middle rod Its corresponding vertical plane force The relationship is: (20)

[0105] Overall lift of drones It can be represented as: (twenty one)

[0106] Step 3: Test the motor speed of the UAV using the UAV performance ground testing and verification platform. Control the UAV to a static state at any angle. Under these conditions, the parameters measured by the UAV performance ground testing and verification platform are all fixed values ​​and do not change over time.

[0107] Establish the relationship between the lift of a single motor and its speed. For a single motor, the lift generated by its rotor rotation... With motor speed They are directly proportional, that is, they satisfy the relational expression. ,in It is the thrust coefficient; the thrust coefficient With air density propeller diameter And related to the geometric design parameters of the propeller, it can be approximated as follows: (in It is a coefficient that integrates all the aerodynamic characteristics of a propeller.

[0108] like Figure 10 As shown, this test case uses a quadcopter drone as the application object, and the propeller geometry design parameters of the four rotors of the quadcopter drone are kept consistent. When the quadcopter drone is in a hovering state, the sum of the lift generated by the rotation of the four rotors is equal to the total weight of the drone. The corresponding mathematical model can be expressed as follows: (in The lift generated by each of the four rotors is respectively. (where is the total weight of the UAV). Replacing the lift of each rotor with its corresponding motor speed expression, we can obtain: ,in Motors The rotational speed. When the quadcopter UAV is in flight, the total lift generated by its four rotors must meet the following requirements. .

[0109] Utilizing the overall lift of the drone Overall slope angle of the drone and the overall yaw angle of the drone Solve for the rotational speeds of the four motors of the drone. Based on the drone control logic in this test case, the final output speed of each motor is determined by the base lift. Pitch control signals Roll control signal and yaw control signals The result is obtained by superposition: final motor speed = base lift + pitch control + roll control + yaw control. The motor speed value can be output by the flight controller, and the specific calculation method is as follows:

[0110] Under static operating conditions, based on the overall lift of the UAV Overall slope angle of the drone and the overall yaw angle of the drone While a solution set consisting of multiple possible solutions for the motor speed can be calculated, a unique solution for the motor speed cannot be determined. This test example solves the problem of no unique solution by using a mixer integrated into the PID controller. Specifically, the mixer can filter standardized solutions that meet preset criteria from the solution set. The mixer has a fixed allocation matrix preset internally. For an X-shaped UAV, its mixing logic is as follows:

[0111] (twenty two)

[0112] in, This represents the base lift distributed by a single motor; pitch control quantity. (in (Pitch moment); Roll control quantity (in (This refers to the rolling moment). It is a constant coefficient that includes the lever arm and layout (overall UAV layout plus rotor structure). This structure does not consider yaw, so the yaw control variable... Therefore, the lift of the four motors of the quadcopter drone can be expressed as: (twenty three)

[0113] Assume that the four motors of the quadcopter drone have equal lever arms from the drone's center of gravity. This lever arm length is denoted as . When the UAV is in a static deflection state (i.e., with a preset deflection angle), its onboard PID controller can calculate the torque required to make the UAV move to the target attitude based on the lift relationship defined above.

[0114] (twenty four)

[0115] Under static equilibrium conditions, the pitching moment pitch angle of the drone Related, satisfying the relational expression Rolling torque With roll angle Related, satisfying the relational expression (in It's about the quality of the drone. It is gravitational acceleration. (where is the vertical distance from the center of gravity of the UAV to the rotor plane). Substituting formula (23) into formula (24), we can obtain the relationship between torque and control quantity: (25)

[0116] Substituting formula (25) into formula (23) yields the lift of the four motors. Total lift of the drone Pitch angle and roll angle Relationship:

[0117] (26)

[0118] The lift generated by each of the four motors of a quadcopter drone is known. Total lift of the drone Pitch angle and roll angle There is a preset correspondence between them. Based on this correspondence, the overall slope angle of the drone can be determined. Overall yaw angle of the drone Solve for the pitch angle of the UAV and roll angle In this test case, the drone's nose is set to point towards the world coordinate system. In the positive direction of the axis, the pitch angle It is a drone orbiting the world coordinate system The angle of rotation of the shaft, the roll angle It is a drone orbiting the world coordinate system The angle of rotation of the axis.

[0119] Based on the above parameter definitions, it is necessary to further establish and solve for the pitch angle. Roll angle Overall slope angle of the drone Overall yaw angle of the drone The mapping relationship between them. The most common implementation method is to solve it through rotation matrix operations:

[0120] 1) After the drone deflects, the drone fuselage... The spatial direction vector of the axis can be represented using spherical coordinates: .

[0121] 2) The ZYX rotation matrix used in this test case is a commonly used matrix for spatial angle transformation, which can establish the UAV body coordinate system and pitch angle. and roll angle The relationship between them, and the specific expression of their combined rotation matrix, is set as follows: ,in, To bypass Axis rotation, and roll angle Rotation matrices that exhibit a mapping relationship To bypass Axis rotation, and pitch angle A rotation matrix that has a mapping relationship. , The model expression is:

[0122] (27)

[0123] (28)

[0124] Calculate the combined rotation matrix:

[0125] (29)

[0126] The drone is initially in a horizontal position, and its coordinate system is as follows: The axial vector (0,0,1) becomes after rotation: (30)

[0127] After the drone rotates, it utilizes the overall slope angle of the drone. and the overall yaw angle of the drone Calculated body coordinate system Axis vectors It should be used in conjunction with the drone using pitch angle and roll angle Calculated body coordinate system Axis vectors The directions are the same, that is: (31)

[0128] Solving the equation, we get:

[0129] (32)

[0130] Pitch angle and roll angle Overall slope angle of the drone and the overall yaw angle of the drone The relationship is: (33)

[0131] Based on the above calculations, the rotational speeds of the four motors of the quadcopter drone are... It can be represented as:

[0132] (34)

[0133] According to formulas (13) and (14), the overall slope angle of the UAV can be analyzed. Overall yaw angle of the drone The dynamic changes. Given a fixed deflection angle for the drone, maintaining a static operating condition, step 1 can also be used to test whether the factory-made drone can achieve the given deflection angle.

[0134] According to formula (21), the lift of the UAV can be analyzed. The dynamic changes. Given a fixed lift value for the drone, maintaining a static operating condition, step 2 can also be used to test whether the factory-made drone can achieve the given lift value.

[0135] According to formula (34), the rotational speeds of the four motors of a quadcopter UAV under static conditions can be analyzed. Given a fixed value for the four motor speeds of a quadcopter drone, maintaining a static operating condition, step 3 can be used to test whether the factory-made drone can achieve the given fixed motor speed value.

[0136] In summary, this test case verifies through reverse derivation that the method proposed in this invention can test whether a factory-produced drone can work normally and accurately achieve given performance indicators such as deflection angle, lift, and motor speed.

[0137] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A ground-based performance testing and verification platform for unmanned aerial vehicles (UAVs), characterized in that, include: The upper circular platform (5) is used to rigidly fix the multi-rotor UAV under test and make the center of gravity of the UAV coaxial with the rotation center of the upper circular platform; A cross-shaped universal joint (6) is provided between the upper truncated cone and the intermediate rod, giving the upper truncated cone the ability to deflect around the X and Y axes with two degrees of freedom. The middle rod (7) is fixed at the upper end to the cross shaft universal joint, and at the lower end is connected to the dynamic force sensor (9) through the dynamic force sensor pressure head (8). The dynamic force sensor (9) is used to collect the overall lift of the UAV in real time. No fewer than three sets of guide rail units, each set of guide rail units including: The guide rail (22) and guide rail slider (23) are used to provide radial translation guidance; The grating ruler slide rail (26) and the grating ruler slider (25) are used to measure the slider displacement in real time; The upper rod (282) and the lower rod (281) are connected in series with a side rod force sensor (29) to obtain the axial force of the rod; The upper ball hinge (272) and the lower ball hinge (271) respectively connect the top of the upper side rod to the upper truncated cone and the bottom of the lower side rod to the slider of the grating ruler, forming a spatial spherical pair; The control and data acquisition system is used to synchronously acquire real-time signals from the dynamic force sensor, side rod force sensor, and grating ruler, and calculate the spatial deflection angle of the upper truncated cone, the overall lift, and the lift distribution of each rotor, thereby completing the performance verification of the UAV in an indoor environment.

2. The UAV performance ground testing and verification platform according to claim 1, characterized in that, It also includes a lower base (1) for overall support and fixing to the ground; a support frame (21) fixed to the lower base; the not less than three sets of guide rail units are evenly distributed along the circumference between the lower base and the upper truncated cone, and the lower base (1) is also fixed with the dynamic force sensor pressure head (8).

3. A ground-based performance testing and verification method for unmanned aerial vehicles (UAVs), employing the platform described in claim 1 or 2, characterized in that, Includes the following steps: S1: Build a verification platform and model it; S2: Fixed installation of the drone; control of the drone with a remote controller; test the drone's deflection angle based on the slider movement distance of the guide rail unit. S3: Based on the detection data from the dynamic force sensor and each guide rail unit, calculate the component force perpendicular to the rotor rotation plane, and calculate the resultant force as the overall lift of the UAV; S4: Control the UAV to be in a static state at any angle. Based on the overall slope angle and overall yaw angle of the UAV, solve for the pitch angle and roll angle, and further calculate the pitch moment and roll moment. Based on the hybrid control logic, select the standardized solution that meets the preset standard from the solution set of motor speeds to obtain the lift of a single motor of the UAV, and further obtain the motor speed.

4. The method for ground testing and verification of UAV performance according to claim 3, characterized in that, In step S1, modeling the verification platform specifically involves defining a coordinate system in the initial horizontal state of the upper frustum. The origin of the coordinate system is the center of rotation of the universal joint. ,point The direction of the line connecting the center of the ball to the upper ball hinge is Positive axis direction shaft edge Rotate the point horizontally counterclockwise by 90 degrees. The positive direction of the axis, the vertical direction is Positive direction of the axis.

5. The method for ground testing and verification of UAV performance according to claim 4, characterized in that, S2 includes: S2.1: Fix the drone in the preset position on the upper circular platform, with the drone's center of gravity aligned with point [missing information]. On the same vertical line, the nose points Positive direction of the axis; S2.2: Use the remote controller to apply a basic lift to the drone rotor and keep it constant, then control the drone's pitch and roll. S2.3: Measure the slider movement distance of each guide rail unit and calculate the slope angle of each guide rail unit direction; combine the obtained slope angle of each guide rail unit direction with the yaw angle of each guide rail unit direction, fit the upper frustum plane after pose transformation and solve the plane equation to obtain the overall slope angle and yaw angle of the plane.

6. The method for ground testing and verification of UAV performance according to claim 5, characterized in that, In S2.3, the slope angle of each guide rail unit is calculated as follows: By combining the vertical distance from the center of each lower ball hinge to the axis of the middle rod in the initial horizontal state with the slider movement distance of its guide rail unit, the length of the line segment connecting point O and the center of each lower ball hinge is calculated. Then, the angle between the upper frustum and the center of the middle rod after the pose transformation is further solved. ; According to the above By determining the positional relationship between the slope angles of each guide rail unit and the slope angles of the guide rail units, which are complementary angles, the slope angles of each guide rail unit can be obtained.

7. A ground-based performance testing and verification method for unmanned aerial vehicles (UAVs) according to claim 3 or 6, characterized in that, S3 includes: Taking the center of the upper ball hinge of each guide rail unit as a fixed point and the center of the upper rod as the direction, a straight line is determined; the drawn straight line is combined with the plane equation to calculate the angle between each upper rod and the plane; this angle is combined with the detected force of each rod force sensor to calculate the lift force perpendicular to the plane measured by each guide rail unit; the lift force perpendicular to the plane measured by the dynamic force sensor is solved using the overall slope angle of the plane and the detected force of the dynamic force sensor. The overall lift of the UAV is obtained by calculating the resultant force of the lift of all guide rail units and the lift obtained from the dynamic force sensor.

8. The method for ground testing and verification of UAV performance according to claim 7, characterized in that, The force detected by each side rod force sensor The specific calculation method is as follows: Apply a force perpendicular to the upper frustum along the center of each upper ball hinge. ,get and The included angle ; The angle between the center of each upper rod and the normal vector of the upper frustum after pose transformation is denoted as . ; and They are vertical angles, hence we get .

9. The method for ground testing and verification of UAV performance according to claim 8, characterized in that, S4 includes: Under the control of the UAV in a static state at any angle, the pitch angle and roll angle are solved based on the mapping relationship between the pitch angle, roll angle and the overall bank angle and overall yaw angle of the UAV; further, the pitch moment is calculated through the pitch angle and the roll moment is calculated through the roll angle. Combining the drone's own hybrid control logic and constant coefficients, the pitch control quantity is calculated based on the pitch moment, the roll control quantity is calculated based on the roll moment, and the overall lift is divided into the basic lift allocated to each motor. Based on the hybrid control logic, standardized solutions that meet the preset standards are selected from the solution set of motor speeds to obtain the lift of a single motor of the UAV, and then the motor speed is obtained.

10. The method for ground testing and verification of UAV performance according to claim 3, characterized in that, Also includes: S5: Place the verification platform in a controllable test environment and accurately simulate various complex external scenarios to capture the drone's deflection angle, lift, and operation data in real time for specific working conditions.

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