Landing trajectory planning method and device for dynamic docking of shipboard aircraft

Abstract

The invention discloses a landing trajectory planning method and device for dynamic docking of a shipboard aircraft. The method and device are used for solving the technical problem that the landing precision of a shipboard sub-aircraft is difficult to guarantee due to an existing shipboard aircraft dynamic docking landing trajectory planning method. The method comprises the following steps: acquiring a scalar distance between a primary aircraft and a secondary aircraft, when the distance between the primary aircraft and the secondary aircraft exceeds a preset allowable error and a preset switching threshold value, firstly calculating a docking preparation point by adopting a geometric positioning method, quickly guiding the secondary aircraft to return to an airspace near the primary aircraft, and further improving the positioning precision by adopting an iterative positioning method, so that the secondary aircraft accurately returns to the position right above the primary aircraft. And finally, in combination with a preset constraint condition and a preset trajectory optimization problem, a preset quasi-Newton optimizer performs trajectory planning according to the flight state data of the carrier-based sub-aircraft at the current moment, and a target landing trajectory corresponding to the carrier-based sub-aircraft is generated.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned aerial vehicles, and in particular to a landing trajectory planning method and device for dynamic docking of carrier-based aircraft. Background Art

[0002] As drone technology matures, carrier-based aircraft are increasingly being used as aerial vehicles, capable of transporting multiple small drones to designated target areas for surveillance, package delivery, and search and rescue missions.

[0003] After the mission is completed, the small UAV can return to the mother aircraft autonomously, which makes up for its limited operating range. In this process, the trajectory planning technology for the carrier-based aircraft to guide the UAV to return and land safely becomes the key. However, most current research focuses on static ground nest docking, usually relying on QR codes or other obvious signs for visual positioning, and using visual target recognition to obtain relative posture during the return process. These nests are generally fixed, so the difficulty is relatively low.

[0004] Existing methods for dynamic docking and landing trajectory planning of carrier-based aircraft mostly rely on GPS positioning or visual positioning to achieve UAV docking. However, in outdoor environments, light changes will interfere with the visual positioning system's accurate recognition of images, causing deviations in the relative position information of the sub-machine obtained; on the other hand, terrain occlusion will not only hinder the reception of GPS signals and affect the accuracy of positioning, but will also further aggravate the difficulty of visual positioning. Under the influence of these unfavorable factors, both GPS positioning and visual positioning will produce large errors. Moreover, as the distance between the mother and child aircraft continues to increase, the visual positioning error will gradually accumulate. This series of problems will cause the positioning accuracy to gradually decrease, making it difficult to guarantee the landing accuracy of the carrier-based sub-machine. Summary of the invention

[0005] The present invention provides a landing trajectory planning method and device for dynamic docking of a carrier-based aircraft, which are used to solve the technical problem that the landing accuracy of a carrier-based sub-aircraft is difficult to ensure due to the existing landing trajectory planning method for dynamic docking of a carrier-based aircraft.

[0006] A first aspect of the present invention provides a landing trajectory planning method for dynamic docking of a carrier-based aircraft, comprising:

[0007] Acquiring a scalar distance between the carrier-based sub-machine and the carrier-based mother machine, and comparing the scalar distance with a preset allowable error;

[0008] If the scalar distance is greater than the preset allowable error, comparing the scalar distance with a preset switching distance;

[0009] If the scalar distance is greater than the preset switching distance, the inertial coordinate position of the docking preparation point is calculated based on the geometric positioning method by using the inertial coordinate reference position of the carrier-based sub-machine, a plurality of waypoints corresponding to the carrier-based sub-machine, and the position difference distance between the carrier-based sub-machine at each waypoint and the carrier-based mother machine;

[0010] Adopting a proportional differential controller to update the real-time position of the inertial coordinate of the carrier-borne sub-machine according to the inertial coordinate position of the docking preparation point, determining the real-time position of the intermediate inertial coordinate of the carrier-borne sub-machine, and calculating the difference of the sub-machine docking point distance between the real-time position of the intermediate inertial coordinate of the carrier-borne sub-machine and the inertial coordinate position of the docking preparation point, and judging whether the difference of the sub-machine docking point distance reaches the preset switching distance;

[0011] If reached, based on an iterative positioning method, the scalar distance is updated by using the flight impact data of the carrier-based sub-machine, the inertial coordinate position of the docking preparation point, and the intermediate inertial coordinate real-time position of the carrier-based sub-machine, to determine an updated scalar distance, and to determine whether the updated scalar distance reaches a preset distance threshold;

[0012] If it is reached, based on the preset constraints, the preset trajectory optimization problem and the preset quasi-Newton optimizer are used to perform trajectory planning according to the current flight status data of the carrier-based sub-aircraft to generate the target landing trajectory corresponding to the carrier-based sub-aircraft.

[0013] Optionally, the geometric positioning method is based on the inertial coordinate reference position of the carrier-based sub-machine, multiple waypoints corresponding to the carrier-based sub-machine, and the position difference distance between the carrier-based sub-machine at each waypoint and the carrier-based mother machine to calculate the inertial coordinate position of the docking preparation point, including:

[0014] Calculate the local coordinate position of the carrier-based mother aircraft according to a plurality of waypoints corresponding to the carrier-based sub-aircraft and the position difference distance between the carrier-based sub-aircraft at each waypoint and the carrier-based mother aircraft;

[0015] Adding the local coordinate position of the carrier-based mother aircraft and the inertial coordinate reference position of the carrier-based sub-aircraft to determine the inertial coordinate position of the carrier-based mother aircraft relative to the carrier-based sub-aircraft;

[0016] The inertial coordinate position of the docking preparation point is calculated by using the inertial coordinate position of the carrier-based mother aircraft relative to the carrier-based sub-aircraft and the local coordinate position of the carrier-based mother aircraft.

[0017] Optionally, the adopting a proportional differential controller to update the inertial coordinate real-time position of the carrier-based sub-machine according to the inertial coordinate position of the docking preparation point to determine the intermediate inertial coordinate real-time position of the carrier-based sub-machine includes:

[0018] Subtracting the inertial coordinate position of the docking preparation point from the inertial coordinate real-time position of the carrier-based sub-machine to determine an error term;

[0019] Using the proportional differential controller to output a speed control signal according to the error term;

[0020] The real-time position of the inertial coordinate of the carrier-based sub-machine is updated based on the speed control signal to determine the real-time position of the intermediate inertial coordinate of the carrier-based sub-machine.

[0021] Optionally, the flight impact data includes an applied disturbance and a two-dimensional vector; and the iterative positioning method is based on which the flight impact data of the carrier-based sub-machine, the inertial coordinate position of the docking preparation point, and the intermediate inertial coordinate real-time position of the carrier-based sub-machine are used to update the scalar distance, and determining the updated scalar distance includes:

[0022] Initializing the two-dimensional vector to determine an initial two-dimensional vector;

[0023] updating the two-dimensional vector based on the initial two-dimensional vector to determine an updated two-dimensional vector;

[0024] The applied disturbance is updated according to the updated two-dimensional vector to determine an updated applied disturbance;

[0025] Calculating the position of the docking preparation point relative to the carrier-based sub-machine by using the inertial coordinate position of the docking preparation point and the intermediate inertial coordinate real-time position of the carrier-based sub-machine;

[0026] Using a preset relative position adaptive estimator, the relative position is calculated according to the position of the docking preparation point relative to the carrier-based sub-machine;

[0027] Using a preset bounded motion controller to calculate the control flight speed of the carrier-based sub-machine according to the relative position and the updated applied disturbance;

[0028] updating the intermediate inertial coordinate real-time position of the carrier-borne sub-machine based on the controlled flight speed of the carrier-borne sub-machine, and determining the target inertial coordinate real-time position of the carrier-borne sub-machine;

[0029] The scalar distance is updated according to the real-time position of the target inertial coordinates of the carrier-based sub-machine, and an updated scalar distance is determined.

[0030] Optionally, it also includes:

[0031] If the scalar distance is less than or equal to the preset switching distance, the inertial coordinate position of the docking preparation point is initialized to determine the initial inertial coordinate position of the docking preparation point;

[0032] Initializing the two-dimensional vector to determine an initial two-dimensional vector;

[0033] updating the two-dimensional vector based on the initial two-dimensional vector to determine an updated two-dimensional vector;

[0034] The applied disturbance is updated according to the updated two-dimensional vector to determine an updated applied disturbance;

[0035] Calculating the position of the docking preparation point relative to the carrier-based sub-machine by using the inertial coordinate position of the initial docking preparation point and the inertial coordinate real-time position of the carrier-based sub-machine;

[0036] Using a preset relative position adaptive estimator, the relative position is calculated according to the position of the docking preparation point relative to the carrier-based sub-machine;

[0037] Using a preset bounded motion controller to calculate the control flight speed of the carrier-based sub-machine according to the relative position and the updated applied disturbance;

[0038] The inertial coordinate real-time position of the carrier-borne sub-machine is updated based on the control flight speed of the carrier-borne sub-machine, and the target inertial coordinate real-time position of the carrier-borne sub-machine is determined;

[0039] The scalar distance is updated according to the real-time position of the target inertial coordinates of the carrier-based sub-machine, and an updated scalar distance is determined.

[0040] Optionally, the step of performing trajectory planning based on preset constraints, using a preset trajectory optimization problem and a preset quasi-Newton optimizer according to the current flight state data of the carrier-based sub-aircraft, and generating a target landing trajectory corresponding to the carrier-based sub-aircraft includes:

[0041] The constraint penalty function corresponding to the preset constraint condition and the preset trajectory optimization problem are transformed by an integral method and a nonlinear transformation method to determine an unconstrained optimization problem;

[0042] The unconstrained optimization problem and the preset constraints are input into a preset quasi-Newton optimizer for calculation to generate a target landing trajectory corresponding to the carrier-based sub-aircraft.

[0043] A second aspect of the present invention provides a landing trajectory planning device for dynamic docking of a carrier-based aircraft, comprising:

[0044] An acquisition module, used to acquire a scalar distance between the carrier-based sub-machine and the carrier-based mother machine, and compare the scalar distance with a preset allowable error;

[0045] A comparison module, configured to compare the scalar distance with a preset switching distance if the scalar distance is greater than the preset allowable error;

[0046] a geometric positioning module, configured to calculate the inertial coordinate position of the docking preparation point based on a geometric positioning method by using the inertial coordinate reference position of the carrier-based sub-machine, a plurality of waypoints corresponding to the carrier-based sub-machine, and the position difference distance between the carrier-based sub-machine at each waypoint and the carrier-based mother machine if the scalar distance is greater than the preset switching distance;

[0047] a position updating module, configured to update the inertial coordinate real-time position of the carrier-borne sub-machine according to the inertial coordinate position of the docking preparation point by using a proportional differential controller, determine the intermediate inertial coordinate real-time position of the carrier-borne sub-machine, calculate the difference in the sub-machine docking point distance between the intermediate inertial coordinate real-time position of the carrier-borne sub-machine and the inertial coordinate position of the docking preparation point, and determine whether the difference in the sub-machine docking point distance reaches the preset switching distance;

[0048] an iterative positioning module, configured to update the scalar distance based on an iterative positioning method by using the flight impact data of the carrier-based sub-machine, the inertial coordinate position of the docking preparation point, and the intermediate inertial coordinate real-time position of the carrier-based sub-machine if the distance is reached, determine the updated scalar distance, and determine whether the updated scalar distance reaches a preset distance threshold;

[0049] The trajectory planning module is used to perform trajectory planning based on the current flight status data of the carrier-based sub-aircraft based on preset constraints, using a preset trajectory optimization problem and a preset quasi-Newton optimizer to generate a target landing trajectory corresponding to the carrier-based sub-aircraft.

[0050] A third aspect of the present invention provides a computer device, comprising a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the processor executes the steps of the landing trajectory planning method for dynamic docking of a carrier-based aircraft as described in any one of the above items.

[0051] A fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed, the steps of the landing trajectory planning method for dynamic docking of carrier-based aircraft as described in any one of the above items are implemented.

[0052] A fifth aspect of the present invention provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions, wherein when the program instructions are executed by a computer, the computer executes the steps of the landing trajectory planning method for dynamic docking of a carrier-based aircraft as described in any one of the above items.

[0053] It can be seen from the above technical solutions that the present invention has the following advantages:

[0054] The above scheme of the present invention provides a landing trajectory planning method for dynamic docking of a carrier-based aircraft. First, a scalar distance between a carrier-based sub-machine and a carrier-based mother machine is obtained, and the scalar distance is compared with a preset allowable error; then, if the scalar distance is greater than the preset allowable error, the scalar distance is compared with a preset switching distance; if the scalar distance is greater than the preset switching distance, based on a geometric positioning method, the inertial coordinate reference position of the carrier-based sub-machine, a plurality of waypoints corresponding to the carrier-based sub-machine, and the position difference distance between the carrier-based sub-machine at each waypoint and the carrier-based mother machine are used to calculate the inertial coordinate position of the docking preparation point; a proportional differential controller is used to update the inertial coordinate real-time position of the carrier-based sub-machine according to the inertial coordinate position of the docking preparation point, determine the intermediate inertial coordinate real-time position of the carrier-based sub-machine, and calculate the difference in the sub-machine docking point distance between the intermediate inertial coordinate real-time position of the carrier-based sub-machine and the inertial coordinate position of the docking preparation point, and judge whether the difference in the sub-machine docking point distance reaches the preset switching distance; if it reaches, based on an iterative positioning method, the flight of the carrier-based sub-machine is used to update the inertial coordinate real-time position of the carrier-based sub-machine The scalar distance is updated based on the impact data, the inertial coordinate position of the docking preparation point, and the real-time position of the intermediate inertial coordinate of the carrier-based sub-machine, the updated scalar distance is determined, and it is judged whether the updated scalar distance reaches the preset distance threshold; finally, if it reaches, based on the preset constraint conditions, the preset trajectory optimization problem and the preset quasi-Newton optimizer are used to perform trajectory planning according to the current flight state data of the carrier-based sub-machine, and generate the target landing trajectory corresponding to the carrier-based sub-machine; Based on the above scheme, when the distance between the mother and child aircraft is too large, that is, the scalar distances between the mother and child aircraft exceed the allowable error and the switching threshold, the present invention first calculates the inertial coordinate position of the docking preparation point based on the geometric positioning method, and reduces the distance between the sub-machine and the mother aircraft to a certain range based on the proportional differential controller, and then switches to the iterative positioning method to continue to reduce the scalar distance between the mother and child aircraft, which can quickly guide the sub-machine back to the airspace near the mother aircraft, so that the sub-machine accurately returns to the top of the mother aircraft, thereby improving the positioning accuracy, and further improving the landing accuracy of the carrier-based sub-machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0056] Figure 1 A flowchart of the steps of a landing trajectory planning method for dynamic docking of a carrier-based aircraft provided in Embodiment 1 of the present invention;

[0057] Figure 2 A trajectory diagram for guiding back to the docking point under noisy conditions using only the iterative positioning method provided in the first embodiment of the present invention;

[0058] Figure 3 A schematic diagram of the relative position deviation of the iterative positioning method provided in the first embodiment of the present invention under noisy conditions;

[0059] Figure 4 This is an enlarged schematic diagram of a relative position deviation of the iterative positioning method provided in the first embodiment of the present invention under noisy conditions;

[0060] Figure 5 A trajectory diagram of the guidance positioning algorithm (geometric positioning method and iterative positioning method) provided in the first embodiment of the present invention guiding back to the docking point under noisy conditions;

[0061] Figure 6 A schematic diagram of the relative position deviation of the guidance positioning algorithm provided in the first embodiment of the present invention under noisy conditions;

[0062] Figure 7 This is an enlarged schematic diagram of a relative position deviation of the guidance positioning algorithm provided in the first embodiment of the present invention under noisy conditions;

[0063] Figure 8 A schematic diagram showing the smoothing approximation function according to the variation of parameters provided in the first embodiment of the present invention;

[0064] Fig. 9 A schematic diagram of the connection between a mother and a child machine in a simulation environment provided in the first embodiment of the present invention;

[0065] Fig.10 A schematic diagram of a mother aircraft from the perspective of a child aircraft camera during a landing process provided in the first embodiment of the present invention;

[0066] Fig.11 A schematic diagram of a landing trajectory generated by using the trajectory planning algorithm of the present invention in the ROS+gazebo environment provided in the first embodiment of the present invention;

[0067] Fig.12 A schematic diagram of a flow chart of guidance and positioning of a carrier-based sub-machine provided in the first embodiment of the present invention;

[0068] Fig.13 A schematic diagram of the operation process of the overall system of a carrier-based aircraft provided in the second embodiment of the present invention;

[0069] Fig.14 This is a structural block diagram of a landing trajectory planning device for dynamic docking of a carrier-based aircraft provided in Embodiment 3 of the present invention. DETAILED DESCRIPTION

[0070] The embodiment of the present invention provides a landing trajectory planning method and device for dynamic docking of a carrier-based aircraft, which are used to solve the technical problem that the landing accuracy of a carrier-based sub-aircraft is difficult to ensure due to the existing landing trajectory planning method for dynamic docking of a carrier-based aircraft.

[0071] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0072] See also Figure 1 , Figure 1 A flowchart of the steps of a landing trajectory planning method for dynamic docking of a carrier-based aircraft provided in Embodiment 1 of the present invention.

[0073] The present invention provides a landing trajectory planning method for dynamic docking of a carrier-based aircraft, comprising:

[0074] Step 101: Obtain a scalar distance between a carrier-based sub-machine and a carrier-based mother machine, and compare the scalar distance with a preset allowable error.

[0075] It should be noted that, because the carrier-based sub-machine is far away from the docking preparation point, under the influence of sensor noise, the estimated value obtained by the iterative positioning method at a long distance may have a large error. Therefore, in order to improve the efficiency of the long-distance guidance task, the geometric positioning method is used in the initial stage to calculate the rough position of the docking point. When the distance between the mother and sub-machine reaches the threshold, that is, the difference in the distance between the docking point of the sub-machine reaches the preset switching distance, the iterative method is switched to guide to the docking point (the inertial coordinate position of the docking preparation point) with a more accurate estimate.

[0076] Furthermore, a UWB sensor (Ultra-Wideband) is used to obtain the distance between the sub-machine (carrier-based sub-machine) and the mother machine (carrier-based mother machine) (scalar distance), and calculate the displacement of the sub-machine in the most recent time interval based on the VIO module (Visual - Inertial Odometry) , compare the scalar distance and the preset allowable error d a Among them, the preset allowable error, the preset switching distance, etc. can be set as needed, and the present invention does not make specific limitations on this.

[0077] Step 102: If the scalar distance is greater than the preset allowable error, compare the scalar distance with the preset switching distance.

[0078] It should be noted that if the scalar distance is less than or equal to the preset allowable error, the remote guidance algorithm is exited, and the sub-aircraft is directly ordered to enter the landing phase, and the current flight status data of the carrier-based sub-aircraft when the scalar distance is less than or equal to the preset allowable error is obtained. Based on the preset constraints, the preset trajectory optimization problem and the preset quasi-Newton optimizer are used to perform trajectory planning according to the current flight status data to generate the target landing trajectory corresponding to the carrier-based sub-aircraft.

[0079] Step 103: If the scalar distance is greater than the preset switching distance, the inertial coordinate position of the docking preparation point is calculated based on the geometric positioning method by using the inertial coordinate reference position of the carrier-based sub-machine, multiple waypoints corresponding to the carrier-based sub-machine, and the position difference distance between the carrier-based sub-machine at each waypoint and the carrier-based mother machine.

[0080] It should be noted that if Greater than the allowable error and greater than the preset switching distance d c , use the inertial coordinate reference position of the sub-machine to establish a local coordinate system, and design 4 waypoints with reference to the regular tetrahedron. After reaching each waypoint, hover for 1 second and obtain the position p of the waypoint in the local coordinate system i , and measure the distance to the mother machine to get the average distance d i , and then use the geometric positioning method to calculate the position p of the docking preparation point in the inertial coordinate system d .

[0081] Specifically, step 103 may include the following sub-steps S31-S33:

[0082] Step S31, calculating the local coordinate position of the carrier-based mother aircraft according to the multiple waypoints corresponding to the carrier-based sub-aircraft and the position difference distance between the carrier-based sub-aircraft at each waypoint and the carrier-based mother aircraft;

[0083] Step S32: adding the local coordinate position of the carrier-based mother aircraft and the inertial coordinate reference position of the carrier-based sub-aircraft to determine the inertial coordinate position of the carrier-based mother aircraft relative to the carrier-based sub-aircraft;

[0084] Step S33: Calculate the inertial coordinate position of the docking preparation point by using the inertial coordinate position of the carrier-based mother aircraft relative to the carrier-based sub-aircraft and the local coordinate position of the carrier-based mother aircraft.

[0085] The waypoint is the target waypoint of the carrier-based sub-aircraft in the local coordinate system, and the multiple waypoints include the first waypoint, the second waypoint, the third waypoint and the fourth waypoint.

[0086] It should be noted that according to the spatial four-point positioning method, if the positions of four points in Cartesian space that are not in the same plane and their distances to a certain point are known, the position of this point can be calculated. The reference position of the sub-machine in the inertial coordinate system (the inertial coordinate reference position of the carrier-based sub-machine) is , is the horizontal coordinate of the inertial coordinate reference position of the carrier-based sub-machine, is the ordinate of the carrier-based sub-machine in the inertial coordinate reference position, is the vertical coordinate of the inertial coordinate reference position of the carrier-based sub-machine.

[0087] Furthermore, the position of the mother aircraft relative to the sub-aircraft (the inertial coordinate position of the carrier-based mother aircraft relative to the carrier-based sub-aircraft) is calculated using VIO (visual positioning module) as Specifically, A local coordinate system with the same attitude as the inertial coordinate system is established for the origin. Next, using the four non-coplanar waypoints corresponding to the slave, the shape of the regular tetrahedron can be referenced. The position of the waypoint in the local coordinate system is described as p i , specifically:

[0088] , , , , ;

[0089] in, is the first waypoint; is the second waypoint; is the third waypoint; is the fourth waypoint; The distance that the carrier-based sub-machine moves at the second waypoint based on the local coordinate system; The distance that the carrier-based sub-machine moves at the third waypoint based on the local coordinate system; The distance that the carrier-based sub-machine moves at the fourth waypoint based on the local coordinate system; is the distance that the carrier-based sub-machine moves at the i-th waypoint based on the local coordinate system; is a constant greater than 1.

[0090] It is worth mentioning that the carrier-based sub-machine can select the appropriate l based on the obstacle information of the surrounding environment. i , thereby obtaining collision-free waypoints, , is the horizontal coordinate of the ith waypoint, is the ordinate of the i-th waypoint, is the vertical coordinate of the i-th waypoint.

[0091] Assume that the position of the mother machine in the local coordinate system is , is the horizontal coordinate of the local coordinate position of the carrier aircraft, is the ordinate of the local coordinate position of the carrier aircraft, The vertical coordinate of the local coordinate position of the carrier-based aircraft. The sub-machine can directly obtain the distance of the mother aircraft by using UWB at each waypoint, and the average distance is obtained by sampling for a certain period of time, that is, the position difference distance d between the waypoint and the carrier-based aircraft. i , according to the distance formula:

[0092] ;

[0093] in, is the position difference between the ith waypoint and the carrier aircraft; is the i-th waypoint; is the local coordinate position of the carrier-based aircraft; is the horizontal coordinate of the i-th waypoint; is the horizontal coordinate of the local coordinate position of the carrier-based aircraft; is the ordinate of the i-th waypoint; is the ordinate of the local coordinate position of the carrier aircraft; is the vertical coordinate of the i-th waypoint; is the vertical coordinate of the local coordinate position of the carrier-based aircraft.

[0094] After simplifying the above formula, we can get:

[0095] ;

[0096] remember , we can get the difference of the formula:

[0097] ;

[0098] in, for and The difference between the distances to the origin; for and The difference between the distances to the origin.

[0099] Convert the formula into matrix expression:

[0100] ;

[0101] ;

[0102] ;

[0103] ;

[0104] Among them, A is the position constraint matrix, and each row of the matrix represents and The difference in xyz coordinates between the two points; b is the error matrix, and each element of b represents the relative deviation in error between the measured distance and the known point, that is, and The difference between the distances to the origin.

[0105] Furthermore, when the four points of the submachine are not in the same plane, the matrix A is invertible. Therefore, the solution formula The position of the carrier aircraft in the local coordinate system can be obtained: , and then Convert to the slave machine's inertial coordinate system, that is, , and obtain the inertial coordinate position of the carrier-based mother aircraft relative to the carrier-based daughter aircraft.

[0106] Furthermore, due to the presence of UWB sensor noise, the estimated value The accuracy decreases when the distance is longer, so the estimated value is considered comprehensively. The initial position of the mother machine calculated using VIO , combined with the reference position of the submachine in inertial coordinates , and the pre-set docking preparation point relative to the mother machine position p dm , we can get the position of the docking preparation point in the inertial coordinate system (inertial coordinate position of the docking preparation point) p d , where the weight satisfy , because the initial position of the mother aircraft obtained by VIO is measured when the daughter aircraft takes off, and when the daughter aircraft performs the mission, the mother aircraft is likely to have a positioning deviation when waiting to hover at the docking point, so the weight should be adjusted to a larger value; among them, the calculation formula of the inertial coordinate position of the docking preparation point is specifically:

[0107] ;

[0108] in, Prepare the inertial coordinate position of the docking point; is the weight.

[0109] Step 104: Use a proportional differential controller to update the inertial coordinate real-time position of the carrier-borne sub-machine according to the inertial coordinate position of the docking preparation point, determine the intermediate inertial coordinate real-time position of the carrier-borne sub-machine, calculate the difference in the sub-machine docking point distance between the intermediate inertial coordinate real-time position of the carrier-borne sub-machine and the inertial coordinate position of the docking preparation point, and determine whether the difference in the sub-machine docking point distance reaches the preset switching distance.

[0110] Specifically, step 104 may include the following sub-steps S41-S43:

[0111] Step S41, subtracting the inertial coordinate position of the docking preparation point from the inertial coordinate real-time position of the carrier-based sub-machine to determine an error term;

[0112] Step S42: using a proportional differential controller to output a speed control signal according to the error term;

[0113] Step S43: updating the real-time position of the inertial coordinates of the carrier-borne sub-machine based on the speed control signal, and determining the real-time position of the intermediate inertial coordinates of the carrier-borne sub-machine.

[0114] It should be noted that after obtaining the target docking position (inertial coordinate position of the docking preparation point) based on the above steps, the present invention uses a PD controller (Proportional-Derivative Controller) to control the slave to move toward the inertial coordinate position of the docking preparation point.

[0115] Specifically, the real-time position of the inertial coordinates of the carrier-based sub-machine during the movement is: , the target position is p d , the error term is , use PD controller to output target speed (speed control signal) ,in, is the horizontal coordinate of the real-time position of the carrier-based sub-machine inertial coordinates, is the ordinate of the real-time position of the carrier-based sub-machine in inertial coordinates, is the vertical coordinate of the real-time position of the carrier-based sub-machine inertial coordinates, is the proportional gain, is the differential gain, is the error term at time k.

[0116] Furthermore, the sub-machine uses the control signal to adjust its speed and move toward the target position, thereby updating the current position, obtaining the real-time position of the intermediate inertial coordinates of the carrier-based sub-machine, and calculating the distance between the sub-machine and the docking point (the difference between the sub-machine docking point distance between the real-time position of the intermediate inertial coordinates of the carrier-based sub-machine and the inertial coordinate position of the docking preparation point) as When the difference in the docking point distance of the sub-machine does not reach the switching distance, the intermediate inertial coordinate real-time position of the carrier-based sub-machine is used as the inertial coordinate real-time position of the new carrier-based sub-machine, and the process jumps to step S41 until the difference in the docking point distance of the sub-machine reaches the preset switching distance, and then switches to the iterative method to more accurately estimate and guide to the docking point (inertial coordinate position of the docking preparation point).

[0117] It is worth mentioning that the PD controller calculates the error term at the current moment and generates a speed control signal based on the proportional and differential gains. The slave uses this control signal to adjust its speed and move toward the target position. At the same time, it updates the current position and enters the next iteration. When the preset switching distance is reached, it enters the next stage and uses the iterative method for precise docking.

[0118] Step 105: If reached, based on the iterative positioning method, the scalar distance is updated using the flight impact data of the carrier-based sub-machine, the inertial coordinate position of the docking preparation point, and the real-time position of the intermediate inertial coordinate of the carrier-based sub-machine, the updated scalar distance is determined, and it is determined whether the updated scalar distance reaches the preset distance threshold.

[0119] Flight impact data includes applied disturbances and two-dimensional vectors.

[0120] It should be noted that when If the difference between the distance between the slave and the docking point reaches the preset switching distance, the first update and Then, the relative position is calculated according to the relative position adaptive estimator (preset relative position adaptive estimator). , and then obtain the speed based on the preset bounded motion controller , so that the carrier-based sub-machine is controlled by presetting a bounded motion controller, thereby updating the real-time position of the inertial coordinates of the carrier-based sub-machine, and continuously reducing the distance between it and the carrier-based mother machine until the relative estimated distance between the sub-machine and the mother machine (updated scalar distance) reaches the target threshold; among them, the target point after calculation iteration (the real-time position of the inertial coordinates of the carrier-based sub-machine) can be expressed as , and finally navigate to the target point through the flight control algorithm, and then re-acquire the scalar distance (updated scalar distance) between the carrier-based sub-machine and the carrier-based mother machine through UWB until the relative estimated distance (updated scalar distance) between the sub-machine and the mother machine reaches the target threshold.

[0121] It is worth mentioning that the present invention calculates the speed Afterwards, the carrier-based sub-machine is controlled based on the preset bounded motion controller to fly towards the mother machine, thereby continuously reducing the scalar distance between the carrier-based sub-machine and the carrier-based mother machine, so that the relative estimated distance between the sub-machine and the mother machine (updated scalar distance) reaches the target threshold.

[0122] Specifically, step 105 may include the following sub-steps S51-S58:

[0123] Step S51, initializing the two-dimensional vector to determine the initial two-dimensional vector;

[0124] Step S52: updating the two-dimensional vector based on the initial two-dimensional vector to determine an updated two-dimensional vector;

[0125] Step S53, updating the applied disturbance according to the updated two-dimensional vector to determine the updated applied disturbance;

[0126] It should be noted that the disturbance applied satisfies ,Right now The norm of is limited to 1 to ensure that the generated internal signal will not increase infinitely, so that the control input is always bounded; and for any , there exists a constant such that ,and ,Right now The linear span of covers all cases where k is from = 0 to = K-1, that is, the generated signal is rich enough to cover the entire signal space; among them, is a three-dimensional Euclidean space, that is, the set of all possible vectors in three-dimensional space, sup is the supremum, that is, the largest upper bound among all possible values, and span is the span of the linear space, that is, the entire linear space generated by a set of vectors.

[0127] Furthermore, the updated perturbation process can be expressed as:

[0128] ;

[0129] in, is the applied disturbance after the update at time k; is the transformation function; is the two-dimensional real number space, that is, the set of all two-dimensional real number vectors; N is the set of natural numbers, that is, the set of all positive integers.

[0130] Furthermore, the two-dimensional vector satisfy ,and , let the initial two-dimensional vector , then the processing process of the updated two-dimensional vector can be expressed as:

[0131] ;

[0132] in, is the updated two-dimensional vector at time k; is the update matrix; is the initial two-dimensional vector; a is the discretization degree and periodicity of the signal period; It is the initial phase of the signal, and the initial value is usually 0.

[0133] It is worth mentioning that , then the mapping:

[0134] ;

[0135] in, is the transformation function; x is the two-dimensional vector in the transformation function; is the first parameter in the transformation function; is the first value of the two-dimensional vector; is the second value of the two-dimensional vector; is the second parameter in the transformation function.

[0136] Step S54, using the inertial coordinate position of the docking preparation point and the real-time inertial coordinate position of the carrier-borne sub-machine, calculate the position of the docking preparation point relative to the carrier-borne sub-machine;

[0137] Step S55, using a preset relative position adaptive estimator to calculate the relative position according to the position of the docking preparation point relative to the carrier-based sub-machine;

[0138] Step S56, using a preset bounded motion controller to calculate the control flight speed of the carrier-based sub-machine according to the relative position and the updated applied disturbance;

[0139] Step S57: updating the inertial coordinate real-time position of the carrier-borne sub-machine based on the carrier-borne sub-machine's flight control speed, and determining the updated inertial coordinate real-time position of the carrier-borne sub-machine;

[0140] Step S58: updating the scalar distance according to the updated inertial coordinate real-time position of the carrier-borne sub-machine, and determining the updated scalar distance.

[0141] It should be noted that the present invention introduces a relative position estimator based on UWB and VIO to calculate the position of the mother aircraft relative to the child aircraft. First, the motion model of the UAV is simplified to a first-order integrator model, the position of the center of mass is selected as the state variable x of the system, and the speed is selected as the input u of the system, that is, , , is the horizontal coordinate of the UAV, is the vertical coordinate of the UAV, is the vertical coordinate of the UAV, is the flight speed corresponding to the horizontal coordinate of the UAV, is the flight speed corresponding to the vertical coordinate of the UAV, is the flight speed corresponding to the vertical coordinate of the UAV; T is the transposition, and the sampling period of the UAV state is t s , then the motion model can be expressed as: .

[0142] Furthermore, VIO is used to obtain the position of the submachine in the inertial coordinate system at time k and speed , then the displacement of the submachine from time k to time (k+1) is ; Among them, displacement It is obtained by onboard sensors rather than by differentiating two consecutive absolute positions.

[0143] Furthermore, it is assumed that the mother aircraft remains in a hovering state during docking, and the position of the mother aircraft in the inertial coordinate system at this time is recorded as , use UWB to get the distance from the main unit to the sub-unit at time k: .

[0144] Furthermore, during the remote guidance phase, the slave needs to navigate to a position near the master, and then use a vision-based relative positioning algorithm for accurate positioning. The present invention describes this position as the docking preparation point p d , the positions of the docking preparation point relative to the slave and master are q k 、p dm ,Right now , The navigation goal of the remote guidance phase can be expressed as making the slave reach the docking preparation point within a certain period of time, that is, .

[0145] Based on the above foundation, we can get ,but:

[0146] ;

[0147] Further, we can get: ;

[0148] Furthermore, a relative position adaptive estimator is constructed based on the above definition, that is, an expression corresponding to the relative position adaptive estimator is preset, specifically:

[0149] ;

[0150] in, is the relative position at time k, indicating the estimated position of the docking preparation point relative to the carrier-based sub-machine at time k; is a mapping or transformation function; is the relative position at time k-1; is the displacement of the carrier-based sub-machine at time k-1; is a constant, satisfying , The maximum permissible speed for the drone to fly; is the estimation error at time k.

[0151] It is worth mentioning that the function The modulus used to constrain the estimated value to be smaller than the measured distance is defined as:

[0152] ;

[0153] in, is a mapping or transformation function; is a mapping or transformation function; is the three-dimensional vector of the incoming function; U is the scalar of the incoming function.

[0154] Furthermore, the estimated error e k Defined as:

[0155] ;

[0156] After simplifying it, we can get:

[0157] ;

[0158] It is worth mentioning that the inertial coordinate position of the docking preparation point and the real-time inertial coordinate position of the carrier-based sub-machine are substituted into the formula , get the inertial coordinate position of the docking preparation point and the real-time inertial coordinate position of the carrier-based sub-machine ,use As initial , and adopt and the scalar distance between the carrier-based sub-machine and the carrier-based mother machine, calculate the estimated error, and then sum the estimated error and Substitute the expression corresponding to the preset relative position adaptive estimator to calculate the relative position.

[0159] Furthermore, in order to make the adaptive estimator formula converge, it is necessary to add a continuous disturbance to the flight of the daughter aircraft until the daughter aircraft reaches the docking preparation point p d Therefore, a bounded motion controller is designed for the slave machine, and its corresponding expression is:

[0160] ;

[0161] in, Control the flight speed of the carrier-based sub-machine at time k; is a mapping or transformation function; is the first constant; is the relative position at time k; The position of the docking preparation point relative to the carrier aircraft; is the second constant; is the disturbance applied after the update at time k.

[0162] It is worth mentioning that represents the feedback control term related to the error of the target position, which is used to guide the system to move towards the target direction, Representation and internal signal Related items are used to increase flexibility or increase the dynamic characteristics within the system; is the disturbance applied at time k, that is, the disturbance applied after the update at time k; the constant , satisfy .

[0163] Further, if the updated scalar distance does not reach the preset distance threshold, the updated scalar distance is used as the new scalar distance, the target inertial coordinate real-time position of the carrier-based sub-aircraft is used as the new intermediate inertial coordinate real-time position of the carrier-based sub-aircraft, the updated two-dimensional vector is used as the new initial two-dimensional vector, the updated applied disturbance is used as the new applied disturbance, and the execution step S52 is jumped until the updated scalar distance reaches the preset distance threshold, and then the current flight state data of the carrier-based sub-aircraft when the updated scalar distance reaches the preset distance threshold is obtained, and the trajectory planning is performed in combination with the preset constraint conditions, the preset trajectory optimization problem, and the preset quasi-Newton optimizer to generate the target landing trajectory corresponding to the carrier-based sub-aircraft.

[0164] Optionally, it also includes:

[0165] If the scalar distance is less than or equal to the preset switching distance, the inertial coordinate position of the docking preparation point is initialized to determine the initial inertial coordinate position of the docking preparation point;

[0166] Initialize the two-dimensional vector and determine the initial two-dimensional vector;

[0167] The two-dimensional vector is updated based on the initial two-dimensional vector to determine an updated two-dimensional vector;

[0168] The applied disturbance is updated according to the updated two-dimensional vector to determine the updated applied disturbance;

[0169] The position of the docking preparation point relative to the carrier-based sub-machine is calculated by using the inertial coordinate position of the initial docking preparation point and the inertial coordinate real-time position of the carrier-based sub-machine;

[0170] The preset relative position adaptive estimator is used to calculate the relative position according to the position of the docking preparation point relative to the carrier-based sub-machine;

[0171] The preset bounded motion controller is used to calculate the control flight speed of the carrier-based sub-machine according to the relative position and the updated applied disturbance;

[0172] The inertial coordinate real-time position of the carrier-borne sub-machine is updated based on the carrier-borne sub-machine's control flight speed, and the target inertial coordinate real-time position of the carrier-borne sub-machine is determined;

[0173] The scalar distance is updated according to the real-time position of the target inertial coordinates of the carrier-based sub-machine, and the updated scalar distance is determined.

[0174] It should be noted that if the scalar distance is less than or equal to the preset switching distance, the geometric positioning method is not used to calculate the inertial coordinate position of the docking preparation point. The inertial coordinate position of the docking preparation point can be randomly assigned as needed to obtain the initial inertial coordinate position of the docking preparation point, and then the scalar distance between the mother and child machines is gradually reduced. The principle of the step for determining the updated scalar distance here is consistent with the principle of the step for determining the updated scalar distance in the above step 105, and the present invention will not be elaborated on.

[0175] For further information, see Figure 2-Figure 4 , only the iterative positioning method proposed in the present invention is used to guide the vehicle back to the docking point under noisy conditions, and the relative position deviation under noisy conditions is obtained ( Figure 3 , Figure 4 The solid line in the figure is the actual deviation, and the dotted line is the estimated deviation calculated by the algorithm). After zooming in on some of the graphs, it can be observed that the error is within a radius of two meters.

[0176] For further information, see Figure 5-Figure 7 , the guidance positioning algorithm proposed in the present invention is used to guide the vehicle back to the docking point under noisy conditions, and the relative position deviation under noisy conditions is obtained ( Figure 5 , Figure 6 The solid line in the figure is the actual deviation, and the dotted line is the estimated deviation solved by the algorithm). After zooming in on some of the graphs, it can be observed that the positioning accuracy is not much different from that of the iterative positioning method alone, but the advantage is that the jitter is smaller and the oscillation frequency is lower. From the simulation, it can be seen that the guided positioning algorithm proposed in the present invention has a faster convergence speed under noisy conditions while maintaining considerable convergence accuracy.

[0177] Step 106: If the condition is met, based on preset constraints, a preset trajectory optimization problem and a preset quasi-Newton optimizer are used to perform trajectory planning according to the current flight status data of the carrier-based sub-aircraft, and a target landing trajectory corresponding to the carrier-based sub-aircraft is generated.

[0178] Specifically, step 106 may include the following sub-steps S61-S62:

[0179] Step S61, transforming the constraint penalty function corresponding to the preset constraint condition and the preset trajectory optimization problem by using the integral method and the nonlinear transformation method to determine the unconstrained optimization problem;

[0180] Step S62: input the unconstrained optimization problem and the preset constraints into the preset quasi-Newton optimizer for calculation to generate the target landing trajectory corresponding to the carrier-based sub-aircraft.

[0181] The preset constraints include dynamic constraints, angular velocity construction constraints, collision distance constraints, relative velocity constraints, acceleration constraints caused by drag force, and field of view angle constraints.

[0182] The flight status data at the current moment includes the position and attitude of the carrier-based sub-aircraft in the inertial coordinate system, the flight speed of the carrier-based sub-aircraft, the acceleration of the carrier-based sub-aircraft, the angular velocity of the horizontal and vertical axes of the carrier-based sub-aircraft, the vertical axis angular velocity of the carrier-based sub-aircraft, the vertical axis height distance between the carrier-based sub-aircraft and the carrier-based mother aircraft, the relative speed between the carrier-based sub-aircraft and the carrier-based mother aircraft, the wind speed and the standard deviation.

[0183] The preset quasi-Newton optimizer is the quasi-Newton L-BFGS (Limited-memory BFGS) optimizer.

[0184] It should be noted that the trajectory optimization problem during the docking process (preset trajectory optimization problem) is specifically:

[0185] ;

[0186] in, is the preset trajectory optimization problem; c is the coefficient matrix in the trajectory; T is the trajectory time; is the s-th derivative of the system state z(t) with respect to time t; is the weight of time cost; is the starting point constraint of the trajectory; is the end point constraint of the trajectory; It is a dynamic constraint, i.e., a preset constraint; It is a set of constraints for a dynamic system, which represents the set that the system state and control input need to satisfy, and is used to limit the feasible state space of the system; is the state of the system at time t; stT means that the total time of the trajectory must be greater than zero.

[0187] It is worth mentioning that is defined as a vector. It contains the state of the trajectory and its first (s-1) order derivatives: ,in, is the original system vector of the system, is the first derivative of the system state, usually the speed or rate of change, describing the change of the state variable. is the higher-order derivative of the system state.

[0188] Furthermore, in the remote guidance stage, the present invention selects the smoothing order s=4, that is, to minimize the square of the Euclidean norm of the fourth-order derivative of the position. According to the differential flatness theory of multi-rotor drones, the torque in the system input is a function of the fourth-order derivative of the position. Therefore, MinimumSnap corresponds to minimizing the differential of the thrust, which can effectively reduce the energy consumption of the drone, thereby improving its endurance. In the precision landing stage, the present invention selects the smoothing order s=3, that is, to minimize the square of the Euclidean norm of the jerk. According to the differential flatness theory of multi-rotor drones, the angular velocity is a function of the third-order derivative of the position. Therefore, MinimumJerk corresponds to minimizing the angular velocity, which is conducive to visual tracking during landing and reduces the probability of label loss.

[0189] Furthermore, during the precision landing phase, although the mother aircraft remains in a hovering state, it may be affected by external interference (such as wind, airflow interference of the daughter aircraft, etc.), resulting in an unstable state. In order to ensure that the daughter aircraft can dock with the mother aircraft accurately and stably, the planner needs to perform high-frequency trajectory replanning. The purpose of trajectory replanning is to continuously adjust the flight trajectory of the daughter aircraft based on the real-time mother aircraft state information so that its final state is consistent with the mother aircraft. The terminal state of the daughter aircraft can be expressed by the following equation:

[0190] ;

[0191] in, is the inertial coordinate position of the carrier-based sub-machine; is the position of the landing target point in the inertial coordinate system; is the inertial coordinate attitude of the carrier-based sub-machine; is the attitude of the landing target point in the inertial coordinate system; is the flight speed of the carrier-based sub-aircraft; is the flight speed of the carrier-based aircraft; For A very small pulling speed is applied in the direction; is the direction vector of the z-axis in the landing coordinate system; is the acceleration of the carrier-based sub-machine.

[0192] It is worth mentioning that the target posture of the above-mentioned end point is to align the posture of the sub-machine with the QR code on the mother machine, and the target position of the end point is a short distance in the positive direction of the z-axis from the solved position of the QR code. This is because the camera's field of view is limited when approaching the final target landing point, and the complete QR code can no longer be seen, that is, the relative position can no longer be obtained. At this time, a very small traction speed in the z-axis direction is added to the end point speed to move the sub-machine to the target docking position, and then the motor is turned off to make the sub-machine dock on the mother machine.

[0193] Furthermore, in order to ensure the smooth motion trajectory of the UAV in space and avoid excessive displacement or sudden acceleration changes, the maximum allowable flight speed is set to v max , the maximum permissible acceleration is a max , establish dynamic constraints:

[0194] ;

[0195] Furthermore, the penalty function corresponding to the dynamic constraint is constructed:

[0196] ;

[0197] in, is the flight speed penalty function corresponding to the dynamic constraint; is the acceleration penalty function corresponding to the dynamic constraint; The mapping transformation defined is used to quantize the penalty size.

[0198] function is defined as:

[0199] ;

[0200] Here, x is the first parameter in the incoming mapping; y is the second parameter in the incoming mapping.

[0201] Furthermore, as the two drones gradually approach docking, it is necessary to ensure the stability of the attitude and avoid docking errors caused by rapid attitude changes. The angular velocity constraint is mainly used to control the attitude change speed of the drone. Attitude control is particularly important for the stable flight and steering of drones. If the angular velocity is not restricted, the drone may rotate violently during attitude adjustment, affecting the overall stability, especially when approaching other aircraft or docking. Therefore, the angular velocity of the drone is divided into two parts, taking into account the roll angle and pitch angle, and limiting the angular velocity of the yaw angle separately. Let w xy,max is the maximum permissible angular velocity of the xy axis, w z,max Construct a constraint for the maximum allowed angular velocity of the z-axis, that is, the angular velocity constraint:

[0202] ;

[0203] in, is the angular velocity of the carrier-based sub-machine along the horizontal and vertical axes at time t; is the vertical axis angular velocity of the carrier-based sub-aircraft at time t.

[0204] Furthermore, the penalty function corresponding to the angular velocity constraint is constructed:

[0205] ;

[0206] in, is the penalty function corresponding to the angular velocity constraint; is a second-order continuously differentiable smooth approximate function of max(x, 0).

[0207] For further information, see Figure 8 , Function at different polishing factors The shape of the following is adjusted by The size of can control the accuracy of the constraint, The function is defined as:

[0208] ;

[0209] in, is the smoothing approximation function; x is the input of the smoothing approximation function.

[0210] Furthermore, since the docking process is carried out in the air, an unsuccessful landing of the sub-machine may touch the propeller of the mother machine and cause a crash. Therefore, the sub-machine needs to be stably kept above the mother machine during the docking process. If vibration or deviation occurs, it will cause damage. The z-axis height constraint of the sub-machine and the mother machine is constructed, and the minimum safe height difference is set to d min , this height difference is related to the effective distance of the sub-machine to recognize the QR code in the final landing stage. If this value is too small, the QR code will be lost in the field of vision and cannot be located. If it is too large, there will be a risk of collision. Suppose the z-axis height of the sub-machine and the mother machine in the docking stage is z c and z m , construct a collision distance constraint:

[0211] ;

[0212] in, It is the vertical axis height distance between the carrier-based sub-machine and the carrier-based mother machine at time t.

[0213] Furthermore, the penalty function corresponding to the collision distance constraint is constructed:

[0214] ;

[0215] in, is the penalty function corresponding to the collision distance constraint; The mapping transformation defined is used to quantize the penalty size.

[0216] Further, The function is defined as:

[0217] ;

[0218] Among them, x is The input to the function.

[0219] Furthermore, during the docking process, it is necessary to control not only the speed of each drone, but also the relative speed between the two drones. Their relative speed near the docking point can be limited to ensure that they approach the docking point slowly and steadily. Reduce shock: When the two drones gradually approach, maintaining a small change in relative speed can reduce the risk of shock or collision caused by speed difference. Set the maximum allowed relative speed v rel,max , construct relative velocity constraints:

[0220] ;

[0221] Furthermore, the penalty function corresponding to the relative speed constraint is constructed:

[0222] ;

[0223] in, is the penalty function corresponding to the relative speed constraint.

[0224] Furthermore, considering the interference of the airflow generated by the mother machine on the daughter machine during docking, an integrated wind speed and direction sensor module is equipped on the UAV. The present invention assumes that the wind speed v w and standard deviation It can be measured by the sensor (the velocities here are all three-dimensional vectors), and the drag force f affects the acceleration of the drone. Usually, the magnitude of the drag force is proportional to the square of the velocity. A common expression is:

[0225] ;

[0226] Where the total wind speed relative to the speed of the drone V is defined as:

[0227] ;

[0228] in, is the wind speed; is the speed of the slave.

[0229] Furthermore, the resulting drag force can be expressed as:

[0230] ;

[0231] Where c is the drag coefficient related to the characteristics of the UAV; Indicates the range of turbulence disturbance in the direction of wind speed

[0232] Furthermore, in order to ensure that the UAV can maintain a stable acceleration in the wind field and avoid loss of control due to turbulence, the present invention can constrain the acceleration caused by the drag force, that is, the acceleration constraint caused by the drag force, specifically:

[0233] ;

[0234] Among them, m is the mass of the sub-machine; is the maximum permissible disturbance acceleration.

[0235] Based on the above foundation, we can get:

[0236] ;

[0237] Furthermore, the penalty function corresponding to the acceleration constraint caused by the drag force is constructed:

[0238] ;

[0239] in, It is the penalty function corresponding to the acceleration constraint caused by the drag force.

[0240] Furthermore, since the docking process relies on the visual QR code detection system, the sub-machine needs to be constrained in the field of view so that the mother machine appears in the field of view in real time. It ensures that the drone's sensors can capture real-time information about the docking point and the surrounding environment to avoid collisions, especially in dynamic environments and targets approaching each other. Assuming r cm is the relative position vector from the slave to the master, u camera is the sight direction unit vector of the slave camera, is the field of view of the drone, is the angle between the relative position vector and the direction of the camera realization.

[0241] Furthermore, the camera of the slave machine needs to ensure that the master machine is always within its field of view, so the field of view angle constraint can be expressed as: ,Right now:

[0242] ;

[0243] ;

[0244] Furthermore, the penalty function corresponding to the field of view angle constraint is constructed:

[0245] ;

[0246] in, is the penalty function corresponding to the field of view constraint.

[0247] Furthermore, the integral method is used to calculate the violations of the continuous time constraints, thereby reducing the infinite number of constraints to a finite number, namely:

[0248] ;

[0249] in, is the total penalty function of the constraint obtained by integrating the continuous time under the *th constraint; is the penalty function corresponding to the preset constraint condition.

[0250] Assume the weight of constraint penalty is , then the constraint penalty received by the slave during the docking process can be summarized as:

[0251] ;

[0252] in, The total penalty of all constraints is accumulated; is the total penalty for flight speed; is the weight factor of the flight speed constraint.

[0253] Furthermore, the trajectory optimization problem with geometric constraints is transformed into an unconstrained optimization problem through the integration method and nonlinear transformation, namely, the unconstrained optimization problem J, which is specifically:

[0254] ;

[0255] For further information, see Figure 9-11 , all constraints are passed into the quasi-Newton L-BFGS (Limited-memory BFGS) optimizer for calculation, so as to obtain a final landing trajectory that satisfies the dynamic constraints and takes into account the airflow interference, that is, the target landing trajectory corresponding to the carrier-based sub-aircraft.

[0256] As a comparison of technical effects, we can refer to existing technologies. The existing research on vehicle-mounted dynamic docking focuses on guided positioning and trajectory planning. Although it also relies on visual recognition technology, unlike airborne docking, vehicle-mounted docking does not need to consider airflow interference. However, research on airborne docking is still relatively rare, and existing airborne docking stations mostly rely on additional robotic arms to complete, which not only increases costs but also increases the complexity of control. Some universities have tried to conduct experiments indoors using motion capture systems, but outdoors, especially in environments with high positioning errors and airflow interference, airborne docking is still at a bottleneck stage and urgently needs further research and breakthroughs.

[0257] Most previous docking algorithms require the landing platform to be visible during the entire mission, because the drone relies on visual information to output control quantities. Although the airborne vision system can effectively solve the docking problem of drones, its coverage is limited and it is difficult to meet the remote guidance needs of drones. The application scenario of airborne docking is that the sub-machine returns to dock after performing a mission. When it returns, it is at a certain distance from the mother machine. At this time, the visual system cannot play a role, and GPS positioning has large errors and cannot be accurately positioned in a GNSS-denied environment. High-precision RTK requires the deployment of corresponding base stations to improve accuracy, which does not meet the application scenario of the airborne docking system. Therefore, a relative positioning algorithm is required to guide the sub-machine to the vicinity of the mother machine. At the same time, for the docking of the machine nest and the vehicle docking system, the airflow between the drone and the machine nest or the drone and the mobile vehicle end has little mutual influence, while for the airborne docking system, the airflow when the mother machine and the sub-machine docking interfere with each other greatly. When the sub-machine is above the mother machine and is ready to dock, the airflow generated by the two will interfere with each other, causing attitude or positioning drift, thereby reducing the success rate of docking. The existing docking system control method rarely considers the interference caused by the influence of airflow.

[0258] In view of the above problems, the present invention proposes a landing trajectory planning method for dynamic docking of carrier-based aircraft, please refer to Fig.12 The present invention combines the relative positioning algorithm of the geometric positioning method and the iterative method, which combines the ultra-wideband technology (Ultra WideBand, UWB) and visual positioning. Under the influence of sensor noise, the estimated value obtained by the iterative positioning method may have a large error and a slow convergence speed as the distance error increases at a long distance; therefore, in order to improve the efficiency of the remote guidance task, the geometric positioning method is used to calculate the rough position of the docking preparation point in the initial stage. When the distance between the sub-machine and the mother machine is reduced to a certain range, the iterative positioning method is switched to obtain a more accurate position estimate. Specifically, when the sub-machine completes the task in the QR code invisible area and is ready to return, it enters the guidance stage and measures the scalar distance between the sub-machine and the mother machine in real time. When the distance is too large, the docking point position and the corresponding posture are first estimated by the geometric positioning method. When the position deviation between the sub-machine and the estimated docking point reaches a given threshold, that is, the preset switching distance, the switching value iterative positioning method continuously reduces the scalar distance between the sub-machine and the mother machine, thereby entering the docking landing stage.

[0259] Furthermore, the present invention equips the slave with an integrated wind speed and direction sensor module, and constrains the acceleration of the slave under the influence of turbulence by observing the sensor data, and establishes a penalty containing field of view angle constraints and airflow interference constraints to reduce the impact of airflow on the system during the docking process.

[0260] In an embodiment of the present invention, the above scheme of the present invention provides a landing trajectory planning method for dynamic docking of a carrier-based aircraft. First, a scalar distance between a carrier-based sub-machine and a carrier-based mother aircraft is obtained, and the scalar distance is compared with a preset allowable error; then, if the scalar distance is greater than the preset allowable error, the scalar distance is compared with a preset switching distance; if the scalar distance is greater than the preset switching distance, based on a geometric positioning method, the inertial coordinate reference position of the carrier-based sub-machine, a plurality of waypoints corresponding to the carrier-based sub-machine, and a position difference distance between the carrier-based sub-machine at each waypoint and the carrier-based mother aircraft are used to calculate the inertial coordinate position of the docking preparation point; a proportional differential controller is used to update the inertial coordinate real-time position of the carrier-based sub-machine according to the inertial coordinate position of the docking preparation point, determine the intermediate inertial coordinate real-time position of the carrier-based sub-machine, and calculate the difference in the sub-machine docking point distance between the intermediate inertial coordinate real-time position of the carrier-based sub-machine and the inertial coordinate position of the docking preparation point, and judge whether the difference in the sub-machine docking point distance reaches the preset switching distance; if it reaches, based on an iterative positioning method, a carrier-based sub-machine is used to update the inertial coordinate real-time position of the carrier-based sub-machine according to the inertial coordinate position of the docking preparation point. The flight impact data of the sub-machine, the inertial coordinate position of the docking preparation point, and the real-time position of the intermediate inertial coordinate of the carrier-based sub-machine are used to update the scalar distance, determine the updated scalar distance, and determine whether the updated scalar distance reaches the preset distance threshold; finally, if it reaches, based on the preset constraint conditions, the preset trajectory optimization problem and the preset quasi-Newton optimizer are used to perform trajectory planning according to the current flight state data of the carrier-based sub-machine, and generate the target landing trajectory corresponding to the carrier-based sub-machine; Based on the above scheme, when the distance between the sub-machine and the mother-machine is too large, that is, the scalar distances between the sub-machine and the mother-machine exceed the allowable error and the switching threshold, the present invention first calculates the inertial coordinate position of the docking preparation point based on the geometric positioning method, and reduces the distance between the sub-machine and the mother-machine to a certain range based on the proportional differential controller, and then switches to the iterative positioning method to continue to reduce the scalar distance between the sub-machine and the mother-machine, which can quickly guide the sub-machine back to the airspace near the mother-machine, so that the sub-machine accurately returns to the top of the mother-machine, thereby improving the positioning accuracy, and further improving the landing accuracy of the carrier-based sub-machine.

[0261] For better explanation, refer to Fig.13 , which shows a schematic diagram of the operation process of the overall system of the carrier-based aircraft provided by the second embodiment of the present invention, and the process is specifically as follows:

[0262] Based on the guidance and return algorithm of the sub-machine proposed in the present invention, the vision-based Apritag relative positioning algorithm, and the trajectory optimization method considering the influence of airflow. At the beginning of the mission, after receiving the mission instruction, the ship-borne UAV carries the sub-machine to the target area. After arriving at the mother machine's docking point, the sub-machine takes off to perform tasks such as monitoring, package delivery, search and rescue. After the mission is completed, since the positioning systems of the sub-machine and the mother machine will produce a certain drift, directly using the coordinate difference between the two for guidance may result in inaccurate guidance and even the risk of colliding with the mother machine. Through the guidance and return algorithm proposed in the present invention, combined with the geometric method of spatial four-point positioning and the iterative method based on vision and distance, the sub-machine can be accurately and efficiently guided back to the top of the mother machine to prepare for docking.

[0263] Furthermore, after a successful return, the sub-machine will be above the mother machine, and a QR code is placed above the mother machine for auxiliary detection. At this time, based on the Apritag (QR code detection system) relative positioning algorithm, the position information of the mother machine fuselage QR code relative to the sub-machine can be obtained. This position information will be converted to the inertial coordinate system of the sub-machine to obtain the real-time position of the mother machine, that is, the target point of trajectory generation. Finally, combined with factors such as dynamic constraints, camera field of view constraints, and airflow interference, the trajectory is optimized to generate a smooth trajectory, successfully guiding the sub-machine to complete precise landing and safely dock with the mother machine.

[0264] Compared with the existing technology, in outdoor environments, the relative position of the sub-machine is often affected by factors such as light changes and terrain occlusion, resulting in large deviations in the GPS or visual positioning system. In particular, after the sub-machine completes its mission, it cannot recognize the QR code at a long distance and cannot rely on the relative positioning method based on Apritag for return, which brings huge challenges to air docking. Once the positioning error exceeds the safety limit, it may cause the mother and child aircraft to collide in the air, resulting in serious consequences.

[0265] Therefore, the present invention provides a landing trajectory planning method for dynamic docking of carrier-based aircraft, aiming to improve the robustness and accuracy of guidance. The geometric method performs positioning through four points that are not coplanar in space, and has the advantages of fast convergence and simple implementation. However, as the distance between the mother and child aircraft increases and the visual positioning error accumulates, the positioning accuracy will gradually decrease, and it is impossible to meet the high-precision requirements. In contrast, although the iterative method can gradually converge to a higher accuracy with the increase in the number of iterations, it takes a long time and is relatively complex to implement. Therefore, when the distance between the two aircraft exceeds the switching threshold, the geometric method is first used to quickly guide the child aircraft back to the airspace near the mother aircraft, and then the iterative method is used to further improve the positioning accuracy, so that the child aircraft accurately returns to the top of the mother aircraft, which not only shortens the guidance time, but also improves the positioning accuracy. When the child aircraft is guided to the top of the mother aircraft, the Apritag-based two-dimensional code-assisted positioning system can accurately obtain the position of the mother aircraft in the child aircraft coordinate system, provide accurate data for subsequent trajectory optimization, and ensure the safe landing of the child aircraft.

[0266] In an embodiment of the present invention, unlike a landing platform on the ground or water surface, an airborne platform will encounter more complex airflow disturbances during docking. During air docking, the downward airflow of the sub-machine will have a significant impact on the mother machine. This uneven turbulence will cause irregular changes in the attitude (such as tilt angle, yaw angle, etc.) of the upper drone, causing the mother machine to drop in height and sway left and right, affecting its flight stability. This airflow disturbance not only increases the attitude instability of the mother machine, but also directly affects the landing accuracy of the sub-machine. Therefore, the present invention introduces a two-dimensional code-assisted positioning system based on Apritag. Due to high-frequency airflow fluctuations, simply relying on the positioning data of the sub-machine itself can no longer ensure high-precision docking. The airflow above the mother machine will be compressed, thereby reducing the maneuverability of the sub-machine when approaching the mother machine, causing obvious hysteresis, making it difficult for traditional trajectory optimization methods to effectively cope with such complex airflow disturbances. In order to overcome these challenges, the present invention combines camera field of view angle constraints with airflow interference compensation technology. During the landing process, by adjusting the camera field of view angle constraints in real time, positioning errors caused by changes in viewing angles can be effectively avoided. At the same time, the airflow interference compensation technology can dynamically adjust the flight trajectory of the sub-machine and reduce the negative impact of airflow on maneuverability. Through the integration of these two technologies, the present invention can ensure the effective correction of the sub-machine landing process in a complex airflow environment, significantly improving the safety and robustness of aerial docking. Ultimately, the sub-machine can land more accurately and stably above the mother machine, thereby completing a safe and precise aerial docking mission.

[0267] See also Fig.14 , Fig.14 This is a structural block diagram of a landing trajectory planning device for dynamic docking of a carrier-based aircraft provided in Embodiment 3 of the present invention.

[0268] The present invention provides a landing trajectory planning device for dynamic docking of a carrier-based aircraft, comprising:

[0269] The acquisition module 1401 is used to acquire the scalar distance between the carrier-based sub-machine and the carrier-based mother machine, and compare the scalar distance with a preset allowable error;

[0270] A comparison module 1402, configured to compare the scalar distance with a preset switching distance if the scalar distance is greater than a preset allowable error;

[0271] The geometric positioning module 1403 is used to calculate the inertial coordinate position of the docking preparation point based on the geometric positioning method by using the inertial coordinate reference position of the carrier-based sub-machine, multiple waypoints corresponding to the carrier-based sub-machine, and the position difference distance between the carrier-based sub-machine at each waypoint and the carrier-based mother machine if the scalar distance is greater than the preset switching distance;

[0272] The position updating module 1404 is used to update the real-time position of the inertial coordinate of the carrier-borne sub-machine according to the inertial coordinate position of the docking preparation point by using a proportional differential controller, determine the real-time position of the intermediate inertial coordinate of the carrier-borne sub-machine, calculate the difference of the docking point distance of the sub-machine between the real-time position of the intermediate inertial coordinate of the carrier-borne sub-machine and the inertial coordinate position of the docking preparation point, and determine whether the difference of the docking point distance of the sub-machine reaches the preset switching distance;

[0273] The iterative positioning module 1405 is used to update the scalar distance based on the iterative positioning method by using the flight impact data of the carrier-based sub-machine, the inertial coordinate position of the docking preparation point, and the real-time position of the intermediate inertial coordinate of the carrier-based sub-machine, if reached, to determine the updated scalar distance, and to determine whether the updated scalar distance reaches the preset distance threshold;

[0274] The trajectory planning module 1406 is used to perform trajectory planning based on the current flight status data of the carrier-based sub-aircraft based on preset constraints, and generate a target landing trajectory corresponding to the carrier-based sub-aircraft.

[0275] Furthermore, the geometric positioning module 1403 is specifically used for:

[0276] Calculate the local coordinate position of the carrier-based mother aircraft according to the multiple waypoints corresponding to the carrier-based sub-aircraft and the position difference distance between the carrier-based sub-aircraft at each waypoint and the carrier-based mother aircraft;

[0277] Adding the local coordinate position of the carrier-based mother aircraft and the inertial coordinate reference position of the carrier-based sub-aircraft to determine the inertial coordinate position of the carrier-based mother aircraft relative to the carrier-based sub-aircraft;

[0278] The inertial coordinate position of the carrier-based mother aircraft relative to the carrier-based daughter aircraft and the local coordinate position of the carrier-based mother aircraft are used to calculate the inertial coordinate position of the docking preparation point.

[0279] Further, the location updating module 1404 is specifically configured to:

[0280] The inertial coordinate position of the docking preparation point and the real-time inertial coordinate position of the carrier-based sub-machine are subtracted to determine the error term;

[0281] A proportional differential controller is used to output a speed control signal according to the error term;

[0282] The real-time position of the inertial coordinates of the carrier-based sub-machine is updated based on the speed control signal to determine the real-time position of the intermediate inertial coordinates of the carrier-based sub-machine.

[0283] Further, the flight impact data includes applied disturbance and two-dimensional vector; the iterative positioning module 1405 is specifically used for:

[0284] Initialize the two-dimensional vector and determine the initial two-dimensional vector;

[0285] The two-dimensional vector is updated based on the initial two-dimensional vector to determine an updated two-dimensional vector;

[0286] The applied disturbance is updated according to the updated two-dimensional vector to determine the updated applied disturbance;

[0287] The position of the docking preparation point relative to the carrier-based sub-machine is calculated by using the inertial coordinate position of the docking preparation point and the real-time position of the intermediate inertial coordinate of the carrier-based sub-machine;

[0288] The preset relative position adaptive estimator is used to calculate the relative position according to the position of the docking preparation point relative to the carrier-based sub-machine;

[0289] The preset bounded motion controller is used to calculate the control flight speed of the carrier-based sub-machine according to the relative position and the updated applied disturbance;

[0290] The real-time position of the intermediate inertial coordinates of the carrier-borne sub-aircraft is updated based on the control flight speed of the carrier-borne sub-aircraft, and the real-time position of the target inertial coordinates of the carrier-borne sub-aircraft is determined;

[0291] The scalar distance is updated according to the real-time position of the target inertial coordinates of the carrier-based sub-machine, and the updated scalar distance is determined.

[0292] Furthermore, it also includes:

[0293] The first module is used for initializing the inertial coordinate position of the docking preparation point if the scalar distance is less than or equal to the preset switching distance, and determining the inertial coordinate position of the initial docking preparation point;

[0294] The second module is used to initialize the two-dimensional vector and determine the initial two-dimensional vector;

[0295] A third module is used to update the two-dimensional vector based on the initial two-dimensional vector and determine an updated two-dimensional vector;

[0296] A fourth module is used to update the applied disturbance according to the updated two-dimensional vector to determine the updated applied disturbance;

[0297] The fifth module is used to calculate the position of the docking preparation point relative to the carrier-based sub-machine by using the inertial coordinate position of the initial docking preparation point and the inertial coordinate real-time position of the carrier-based sub-machine;

[0298] The sixth module is used to calculate the relative position according to the position of the docking preparation point relative to the carrier-based sub-machine by using a preset relative position adaptive estimator;

[0299] The seventh module is used to calculate the control flight speed of the carrier-based sub-machine according to the relative position and the updated applied disturbance using a preset bounded motion controller;

[0300] An eighth module is used to update the real-time position of the inertial coordinates of the carrier-borne sub-machine based on the control flight speed of the carrier-borne sub-machine, and determine the target real-time position of the inertial coordinates of the carrier-borne sub-machine;

[0301] The ninth module is used to update the scalar distance according to the real-time position of the target inertial coordinates of the carrier-based sub-machine and determine the updated scalar distance.

[0302] Furthermore, the trajectory planning module 1406 is specifically used to:

[0303] The constraint penalty function corresponding to the preset constraint conditions and the preset trajectory optimization problem are transformed by the integral method and the nonlinear transformation method to determine the unconstrained optimization problem;

[0304] The unconstrained optimization problem and preset constraints are input into the preset quasi-Newton optimizer for calculation to generate the target landing trajectory corresponding to the carrier-based sub-aircraft.

[0305] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices and modules can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0306] An embodiment of the present invention further provides a computer device, including a memory and a processor, wherein a computer program is stored in the memory; when the computer program is executed by the processor, the processor executes the steps of the landing trajectory planning method for dynamic docking of a carrier-based aircraft as described in the first embodiment above.

[0307] An embodiment of the present invention further provides a computer-readable storage medium having a computer program / instruction stored thereon. When the computer program / instruction is executed by a processor, the steps of the landing trajectory planning method for dynamic docking of a carrier-based aircraft as described in the first embodiment above are implemented.

[0308] An embodiment of the present invention further provides a computer program product, including a computer program / instruction, which, when executed by a processor, implements the steps of the landing trajectory planning method for dynamic docking of a carrier-based aircraft as described in the first embodiment above.

[0309] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0310] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0311] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A landing trajectory planning method for dynamic docking of carrier-based aircraft, characterized in that: include: Acquiring a scalar distance between the carrier-based sub-machine and the carrier-based mother machine, and comparing the scalar distance with a preset allowable error; If the scalar distance is greater than the preset allowable error, comparing the scalar distance with a preset switching distance; If the scalar distance is greater than the preset switching distance, the inertial coordinate position of the docking preparation point is calculated based on the geometric positioning method by using the inertial coordinate reference position of the carrier-based sub-machine, a plurality of waypoints corresponding to the carrier-based sub-machine, and the position difference distance between the carrier-based sub-machine at each waypoint and the carrier-based mother machine; Adopting a proportional differential controller to update the real-time position of the inertial coordinate of the carrier-borne sub-machine according to the inertial coordinate position of the docking preparation point, determining the real-time position of the intermediate inertial coordinate of the carrier-borne sub-machine, and calculating the difference of the sub-machine docking point distance between the real-time position of the intermediate inertial coordinate of the carrier-borne sub-machine and the inertial coordinate position of the docking preparation point, and judging whether the difference of the sub-machine docking point distance reaches the preset switching distance; If reached, based on an iterative positioning method, the scalar distance is updated by using the flight impact data of the carrier-based sub-machine, the inertial coordinate position of the docking preparation point, and the intermediate inertial coordinate real-time position of the carrier-based sub-machine, to determine an updated scalar distance, and to determine whether the updated scalar distance reaches a preset distance threshold; If it is reached, based on the preset constraints, the preset trajectory optimization problem and the preset quasi-Newton optimizer are used to perform trajectory planning according to the current flight status data of the carrier-based sub-aircraft to generate the target landing trajectory corresponding to the carrier-based sub-aircraft.

2. The landing trajectory planning method for dynamic docking of carrier-based aircraft according to claim 1, characterized in that: The method based on the geometric positioning method uses the inertial coordinate reference position of the carrier-based sub-machine, a plurality of waypoints corresponding to the carrier-based sub-machine, and the position difference distance between the carrier-based sub-machine at each waypoint and the carrier-based mother machine to calculate the inertial coordinate position of the docking preparation point, including: Calculate the local coordinate position of the carrier-based mother aircraft according to a plurality of waypoints corresponding to the carrier-based sub-aircraft and the position difference distance between the carrier-based sub-aircraft at each waypoint and the carrier-based mother aircraft; Adding the local coordinate position of the carrier-based mother aircraft and the inertial coordinate reference position of the carrier-based sub-aircraft to determine the inertial coordinate position of the carrier-based mother aircraft relative to the carrier-based sub-aircraft; The inertial coordinate position of the docking preparation point is calculated by using the inertial coordinate position of the carrier-based mother aircraft relative to the carrier-based sub-aircraft and the local coordinate position of the carrier-based mother aircraft.

3. The landing trajectory planning method for dynamic docking of carrier-based aircraft according to claim 1, characterized in that: The adopting a proportional differential controller to update the real-time position of the inertial coordinate of the carrier-based sub-machine according to the inertial coordinate position of the docking preparation point to determine the real-time position of the intermediate inertial coordinate of the carrier-based sub-machine includes: Subtracting the inertial coordinate position of the docking preparation point from the inertial coordinate real-time position of the carrier-based sub-machine to determine an error term; Using the proportional differential controller to output a speed control signal according to the error term; The real-time position of the inertial coordinate of the carrier-based sub-machine is updated based on the speed control signal to determine the real-time position of the intermediate inertial coordinate of the carrier-based sub-machine.

4. The landing trajectory planning method for dynamic docking of carrier-based aircraft according to claim 1, characterized in that: The flight impact data includes an applied disturbance and a two-dimensional vector; the iterative positioning method is based on the flight impact data of the carrier-based sub-machine, the inertial coordinate position of the docking preparation point, and the intermediate inertial coordinate real-time position of the carrier-based sub-machine to update the scalar distance, and determine the updated scalar distance, including: Initializing the two-dimensional vector to determine an initial two-dimensional vector; updating the two-dimensional vector based on the initial two-dimensional vector to determine an updated two-dimensional vector; The applied disturbance is updated according to the updated two-dimensional vector to determine an updated applied disturbance; Calculating the position of the docking preparation point relative to the carrier-based sub-machine by using the inertial coordinate position of the docking preparation point and the intermediate inertial coordinate real-time position of the carrier-based sub-machine; Using a preset relative position adaptive estimator, the relative position is calculated according to the position of the docking preparation point relative to the carrier-based sub-machine; Using a preset bounded motion controller to calculate the control flight speed of the carrier-based sub-machine according to the relative position and the updated applied disturbance; updating the intermediate inertial coordinate real-time position of the carrier-borne sub-machine based on the controlled flight speed of the carrier-borne sub-machine, and determining the target inertial coordinate real-time position of the carrier-borne sub-machine; The scalar distance is updated according to the real-time position of the target inertial coordinates of the carrier-based sub-machine, and an updated scalar distance is determined.

5. The landing trajectory planning method for dynamic docking of carrier-based aircraft according to claim 4, characterized in that: Also includes: If the scalar distance is less than or equal to the preset switching distance, the inertial coordinate position of the docking preparation point is initialized to determine the initial inertial coordinate position of the docking preparation point; Initializing the two-dimensional vector to determine an initial two-dimensional vector; updating the two-dimensional vector based on the initial two-dimensional vector to determine an updated two-dimensional vector; The applied disturbance is updated according to the updated two-dimensional vector to determine an updated applied disturbance; Calculating the position of the docking preparation point relative to the carrier-based sub-machine by using the inertial coordinate position of the initial docking preparation point and the inertial coordinate real-time position of the carrier-based sub-machine; Using a preset relative position adaptive estimator, the relative position is calculated according to the position of the docking preparation point relative to the carrier-based sub-machine; Using a preset bounded motion controller to calculate the control flight speed of the carrier-based sub-machine according to the relative position and the updated applied disturbance; updating the real-time position of the inertial coordinates of the carrier-borne sub-machine based on the controlled flight speed of the carrier-borne sub-machine, and determining the target real-time position of the inertial coordinates of the carrier-borne sub-machine; The scalar distance is updated according to the real-time position of the target inertial coordinates of the carrier-based sub-machine, and an updated scalar distance is determined.

6. The landing trajectory planning method for dynamic docking of carrier-based aircraft according to claim 1, characterized in that: The method of performing trajectory planning based on the preset constraint conditions, using the preset trajectory optimization problem and the preset quasi-Newton optimizer according to the current flight state data of the carrier-based sub-aircraft, and generating a target landing trajectory corresponding to the carrier-based sub-aircraft includes: The constraint penalty function corresponding to the preset constraint condition and the preset trajectory optimization problem are transformed by an integral method and a nonlinear transformation method to determine an unconstrained optimization problem; The unconstrained optimization problem and the preset constraints are input into a preset quasi-Newton optimizer for calculation to generate a target landing trajectory corresponding to the carrier-based sub-aircraft.

7. A landing trajectory planning device for dynamic docking of carrier-based aircraft, characterized in that: include: An acquisition module, used to acquire a scalar distance between the carrier-based sub-machine and the carrier-based mother machine, and compare the scalar distance with a preset allowable error; A comparison module, configured to compare the scalar distance with a preset switching distance if the scalar distance is greater than the preset allowable error; a geometric positioning module, configured to calculate the inertial coordinate position of the docking preparation point based on a geometric positioning method by using the inertial coordinate reference position of the carrier-based sub-machine, a plurality of waypoints corresponding to the carrier-based sub-machine, and the position difference distance between the carrier-based sub-machine at each waypoint and the carrier-based mother machine if the scalar distance is greater than the preset switching distance; a position updating module, configured to update the inertial coordinate real-time position of the carrier-borne sub-machine according to the inertial coordinate position of the docking preparation point by using a proportional differential controller, determine the intermediate inertial coordinate real-time position of the carrier-borne sub-machine, calculate the difference in the sub-machine docking point distance between the intermediate inertial coordinate real-time position of the carrier-borne sub-machine and the inertial coordinate position of the docking preparation point, and determine whether the difference in the sub-machine docking point distance reaches the preset switching distance; an iterative positioning module, configured to update the scalar distance based on an iterative positioning method by using the flight impact data of the carrier-based sub-machine, the inertial coordinate position of the docking preparation point, and the intermediate inertial coordinate real-time position of the carrier-based sub-machine if the distance is reached, determine the updated scalar distance, and determine whether the updated scalar distance reaches a preset distance threshold; The trajectory planning module is used to perform trajectory planning based on the current flight status data of the carrier-based sub-aircraft based on preset constraints, using a preset trajectory optimization problem and a preset quasi-Newton optimizer to generate a target landing trajectory corresponding to the carrier-based sub-aircraft.

8. A computer device, characterized in that: The method comprises a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the processor executes the steps of the landing trajectory planning method for dynamic docking of a carrier-based aircraft according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed, the landing trajectory planning method for dynamic docking of a carrier-based aircraft according to any one of claims 1 to 6 is implemented.

10. A computer program product, characterized in that The computer program product includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions, wherein when the program instructions are executed by a computer, the computer executes the landing trajectory planning method for dynamic docking of a carrier-based aircraft according to any one of claims 1 to 6.

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