Trajectory tracking method, device, equipment, medium and ornithopter

Abstract

The invention relates to the technical field of aircrafts, and discloses a trajectory tracking method, device and equipment, a medium and a flapping-wing aircraft, and the method comprises the steps: determining the current position and the current speed of the aircraft; determining a guidance distance of the aircraft according to the current speed; the guidance distance and the current speed are in a positive correlation relationship; selecting a reference point on the target path of the aircraft; the reference distance between the reference point and the current position is matched with the guidance distance; determining a deflection angle between the reference line of sight and the current speed; the reference sight line is the sight line from the current position to the reference point; determining a centripetal acceleration for controlling the aircraft to move along the target path according to the current speed, the reference distance and the deflection angle; and controlling the steering of the aircraft according to the centripetal acceleration. According to the method, the centripetal acceleration of the aircraft is determined by using the guidance algorithm with prediction capability, the guidance distance is positively correlated with the current speed, and the trajectory tracking effect is good.

Description

Technical Field

[0001] The present invention relates to the technical field of aircraft, and particularly to a trajectory tracking method, device, equipment, medium and flapping-wing aircraft. Background Art

[0002] At present, there are many types of unmanned aircraft. According to their wings, they are mainly divided into rotors, fixed wings, and flapping wings. Different wings have very different flight methods and phenomena. The flight of rotors and fixed wings is relatively stable and the controllability is relatively strong. However, the flight of flapping wings has relatively severe vibrations, a relatively large body inertia, a relatively large dynamic response delay, and is relatively difficult to control. However, it has good bionic characteristics and good concealment, so it has high research value.

[0003] Due to the relatively strong body inertia of the flapping-wing aircraft, there is usually a relatively large delay when tracking the target trajectory. Most of the current trajectory tracking algorithms applicable to rotors and fixed wings are not suitable for application on flapping-wing aircraft and cannot achieve an ideal tracking effect. Summary of the Invention

[0004] In view of this, the present invention provides a trajectory tracking method, device, equipment, medium and flapping-wing aircraft to solve the problem of poor tracking effect of flapping-wing aircraft.

[0005] In a first aspect, the present invention provides a trajectory tracking method, including:

[0006] Determine the current position and current speed of the aircraft;

[0007] Determine the guidance distance of the aircraft according to the current speed; there is a positive correlation between the guidance distance and the current speed;

[0008] Select a reference point on the target path of the aircraft; the reference distance between the reference point and the current position matches the guidance distance;

[0009] Determine the deflection angle between the reference line of sight and the current speed; the reference line of sight is the line of sight from the current position to the reference point;

[0010] Determine the centripetal acceleration for controlling the aircraft to move along the target path according to the current speed, the reference distance and the deflection angle;

[0011] Control the turning of the aircraft according to the centripetal acceleration.

[0012] In some alternative embodiments, the step of selecting a reference point on the target path of the aircraft includes:

[0013] Determine the positional relationship between the reference circle and the target path; the reference circle is a circle with the current position as the center and the guidance distance as the radius;

[0014] In the case where the positional relationship is intersection, among the two common points between the reference circle and the target path, the common point closer to the end point of the target path is used as the reference point;

[0015] In the case where the positional relationship is tangency, the tangent point between the reference circle and the target path is used as the reference point.

[0016] In some alternative embodiments, selecting a reference point on the target path of the aircraft further includes:

[0017] In the case where the positional relationship is intersection or tangency, determine the coordinates of the common point or the tangent point according to whether the target path is parallel to the coordinate axes;

[0018] Among them, in the case where the positional relationship is intersection, if the target path is parallel to the X-axis, the coordinates of the common point are:

[0019]

[0020] If the target path is parallel to the Y-axis, the coordinates of the common point are:

[0021]

[0022] If the target path is not parallel to the coordinate axes, the coordinates of the common point are:

[0023]

[0024] In the case where the positional relationship is tangency, if the target path is parallel to the X-axis, the coordinates of the tangent point are:

[0025]

[0026] If the target path is parallel to the Y-axis, the coordinates of the tangent point are:

[0027]

[0028] If the target path is not parallel to the coordinate axes, the coordinates of the tangent point are:

[0029]

[0030] Among them, (x r ,y r ) represents the coordinates of the common point, (x t ,yt ) represents the coordinates of the tangent point, (x c , y c ) represents the coordinates of the current position, (x 0 , y 0 ) represents the coordinates of the starting point or the ending point of the target path, L 1 represents the guidance distance, k represents the slope of the target path, and b represents the intercept of the target path.

[0031] In some alternative embodiments, selecting a reference point on the target path of the aircraft further includes:

[0032] In the case where the positional relationship is separation, taking the perpendicular point from the current position to the target path as the reference point.

[0033] In some alternative embodiments, selecting a reference point on the target path of the aircraft further includes:

[0034] In the case where the positional relationship is separation, determining the coordinates of the common point or the tangent point according to whether the target path is parallel to the coordinate axes;

[0035] Among them, in the case where the positional relationship is separation, if the target path is parallel to the X-axis, the coordinates of the perpendicular point are:

[0036]

[0037] If the target path is parallel to the Y-axis, the coordinates of the perpendicular point are:

[0038]

[0039] If the target path is not parallel to the coordinate axes, the coordinates of the perpendicular point are:

[0040]

[0041] Among them, (x v , y v ) represents the coordinates of the perpendicular point, (x c , y c ) represents the coordinates of the current position, (x 0 , y 0 ) represents the coordinates of the starting point or the ending point of the target path, k represents the slope of the target path, and b represents the intercept of the target path.

[0042] In some alternative embodiments, determining the positional relationship between the reference circle and the target path includes:

[0043] Determine the vertical distance between the current position and the target path;

[0044] When the vertical distance is less than the guidance distance, the positional relationship between the reference circle and the target path is intersection;

[0045] When the vertical distance is equal to the guidance distance, the positional relationship between the reference circle and the target path is tangency;

[0046] When the vertical distance is greater than the guidance distance, the positional relationship between the reference circle and the target path is separation.

[0047] In some alternative embodiments, determining the deflection angle between the reference line of sight and the current speed includes:

[0048] Determine the line-of-sight angle between the reference line of sight and the reference line, and determine the speed angle between the current speed and the reference line;

[0049] Take the difference between the line-of-sight angle and the speed angle as the deflection angle between the reference line of sight and the current speed.

[0050] In some alternative embodiments, the line-of-sight angle is:

[0051] And,

[0052] The speed angle is:

[0053] And,

[0054] where q represents the line-of-sight angle, σ represents the speed angle, (x p , y p ) represents the coordinates of the reference point, (x c , y c ) represents the coordinates of the current position, (x c0 , y c0 ) represents the coordinates of the historical position when the aircraft moves along the target path.

[0055] In a second aspect, the present invention provides a trajectory tracking device, including:

[0056] A parameter determination module for determining the current position and the current speed of the aircraft;

[0057] A distance setting module for determining the guidance distance of the aircraft according to the current speed; there is a positive correlation between the guidance distance and the current speed;

[0058] A processing module, configured to select a reference point on a target path of the aircraft; a reference distance between the reference point and the current position matches the guidance distance; determine a deflection angle between a reference line of sight and the current speed; the reference line of sight is a line of sight between the current position and the reference point; determine a centripetal acceleration for controlling the aircraft to move along the target path according to the current speed, the reference distance, and the deflection angle.

[0059] A control module, configured to control the turning of the aircraft according to the centripetal acceleration.

[0060] In a third aspect, the present invention provides a computer device, including: a memory and a processor, which are communicatively connected to each other. The memory stores computer instructions, and the processor executes the computer instructions to execute the trajectory tracking method according to the first aspect or any corresponding embodiment thereof.

[0061] In a fourth aspect, the present invention provides a computer-readable storage medium, on which computer instructions are stored, and the computer instructions are used to cause a computer to execute the trajectory tracking method according to the first aspect or any corresponding embodiment thereof.

[0062] In a fifth aspect, the present invention provides a flapping-wing aircraft, including: a fuselage, a controller, and an actuator controlled by the controller; the controller is configured to execute the trajectory tracking method according to the first aspect or any corresponding embodiment thereof.

[0063] The present invention determines a guidance distance positively correlated with the current speed of the aircraft, and then can select a reference point on the target path that matches the guidance distance. Using a guidance algorithm with predictive ability, the centripetal acceleration of the aircraft can be determined, so that the aircraft can be controlled to approach the pre-planned target path and perform trajectory tracking flight along the target path, and finally reach the specified position. The guidance distance is positively correlated with the current speed, and a suitable reference point can be determined in real time based on the speed of the aircraft, and the trajectory tracking effect is better. When applied to a flapping-wing aircraft, it can realize the turning prediction of the flapping-wing aircraft, overcome difficulties such as the response lag of the flapping-wing aircraft, and achieve an ideal satellite positioning and navigation trajectory tracking effect. Description of the Drawings

[0064] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the related art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the related art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0065] Figure 1 It is a schematic flow chart of a trajectory tracking method according to an embodiment of the present invention;

[0066] Figure 2 It is a schematic diagram of calculating centripetal acceleration based on the L1 guidance algorithm according to an embodiment of the present invention;

[0067] Figure 3 It is a schematic flow chart of another trajectory tracking method according to an embodiment of the present invention;

[0068] Figure 4 It is a schematic diagram when the reference circle and the target path intersect according to an embodiment of the present invention;

[0069] Figure 5 It is a schematic diagram when the reference circle and the target path are tangent according to an embodiment of the present invention;

[0070] Figure 6 It is a schematic diagram when the reference circle and the target path are separated according to an embodiment of the present invention;

[0071] Figure 7 It is a schematic diagram of calculating centripetal acceleration in real time according to an embodiment of the present invention;

[0072] Figure 8 It is a structural block diagram of a trajectory tracking device according to an embodiment of the present invention;

[0073] Figure 9 It is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. Detailed implementation manners

[0074] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0075] The power of a rotary-wing and fixed-wing aircraft comes from the airflow generated by the propeller. The generation time is extremely short, basically generated when the propeller starts to rotate. The magnitude of the generated airflow is controllable and stable according to the rotational speed of the propeller. Therefore, the response of the aircraft body changing from a relatively stable state to a maneuvering state is very timely and well controlled. When in a high-maneuvering state, the aircraft body is also relatively stable, and the influence of the inertia of the aircraft body can be better overcome.

[0076] The characteristics of a bionic flapping-wing aircraft have the following impacts on the flight process:

[0077] 1. The wing flapping has periodic vibrations, which have a greater impact on devices and instruments such as sensors and signal receivers loaded on the aircraft. Especially for signal reception, the vibrations will cause the receiving surface to constantly change, which will have a certain impact.

[0078] 2. The body inertia of the bionic flapping-wing aircraft is relatively strong. When changing from a relatively stable flight state to a highly maneuverable state and about to complete climbing, descending in altitude or turning, it takes a relatively long time to complete.

[0079] 3. It is relatively difficult to control the attitude and flight speed of the bionic flapping-wing aircraft. Since the main source of flight power of the flapping-wing aircraft is the airflow force brought by the wing flapping and the torque generated by changing the shape of the tail wing to cause airflow changes, the control response of the aircraft body is much slower than that of the rotary-wing and fixed-wing aircraft.

[0080] Most of the existing general satellite navigation trajectory tracking methods are applicable to rotary-wing and fixed-wing aircraft. Since the maneuverability of rotary-wing and fixed-wing aircraft is stronger than that of flapping-wing aircraft, when rotary-wing and fixed-wing aircraft track the path planned by satellite positioning, their tracking ability and tracking effect are better, and general navigation algorithms are sufficient to meet the navigation tracking purposes of most scenarios of rotary-wing and fixed-wing aircraft. However, for flapping-wing aircraft, their dynamic characteristics are poor. Firstly, there are periodic vibrations brought by wing flapping; secondly, the body inertia is relatively strong, and there will be a large delay due to the large body inertia when turning or restoring the body balance; finally, it is relatively difficult to control the attitude and flight speed, etc. Since the main sources of flight power of the flapping-wing aircraft are the airflow force brought by the wing flapping and the torque generated by changing the shape of the tail wing to cause airflow changes, both of these power sources have a large delay, and the action response is much slower than that of rotary-wing and fixed-wing aircraft. Therefore, most general satellite navigation trajectory tracking algorithms are not suitable for application on flapping-wing aircraft and cannot achieve an ideal tracking effect.

[0081] Due to a certain time interval (about once per second) for obtaining satellite positioning information, the flight speed of the bionic flapping-wing aircraft is about 8 m / s. Such a long time interval results in a long delay in the calculated positioning information and heading angle information, which will also affect the control effect of the flapping-wing aircraft.

[0082] According to an embodiment of the present invention, an embodiment of a trajectory tracking method is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than here.

[0083] In this embodiment, a trajectory tracking method is provided, which can be applied to the controller of an aircraft, and this controller can be, for example, a single-chip microcomputer. Figure 1 It is a flowchart of the trajectory tracking method according to an embodiment of the present invention, asFigure 1 As shown in the figure, the process includes the following steps.

[0084] Step S101: Determine the current position and current speed of the aircraft.

[0085] In this embodiment, during the flight of the aircraft, the flight trajectory of the aircraft can be preset in advance, and the aircraft is controlled to fly along the trajectory to achieve trajectory tracking of the aircraft. The aircraft can specifically be an ornithopter, or a rotorcraft or a fixed-wing aircraft.

[0086] Among them, the trajectory of the aircraft is provided with a starting point and an ending point; if the trajectory of the aircraft is a straight line, it has one starting point and one ending point, and at this time, the entire path corresponding to the trajectory can be used as the target path of the aircraft; alternatively, if the trajectory of the aircraft is a curve, it can be segmented, and the trajectory can be divided into multiple straight-line paths, and each path can be used as the target path of the aircraft. Subsequently, the tracking process of one of the target paths will be taken as an example for description.

[0087] Specifically, during the flight of the aircraft, its position and speed, that is, the current position and current speed, can be determined in real time. For example, the current position and speed of the aircraft can be determined based on satellite positioning, or the current speed of the aircraft can be determined based on the sensors of the aircraft itself; among them, the current speed specifically can include the magnitude and direction of the current speed.

[0088] For example, the aircraft is equipped with sensors for collecting the motion parameters of the aircraft. For example, an ornithopter has a six-axis sensor, a satellite positioning module, etc. Based on these sensors, the position, speed, etc. of the aircraft can be collected in real time. Among them, the data collected by the sensors can be sent to a controller such as a single-chip microcomputer through serial port or bus communication for processing and calculation, so that the controller can process all the acquired real-time data online during the flight. The controller of the aircraft calculates according to the acquired real-time data, obtains the corresponding control quantity, and transmits it to the actuator for action response.

[0089] Optionally, if the current position of the aircraft is determined based on satellite positioning, the directly determined position information is the longitude and latitude coordinates of the aircraft, and the longitude and latitude coordinates need to be converted into spatial coordinates that are easy to calculate, and a corresponding inertial coordinate system (such as a geodetic coordinate system) needs to be established. Among them, since the trajectory tracking method provided in this embodiment mainly involves the steering control of the aircraft in a certain plane, a plane coordinate system can be set only.

[0090] Specifically, a geodetic coordinate system can be constructed with the due north direction of the longitude of the geodetic coordinates as the positive direction of the X-axis, the due east direction of the longitude of the geodetic coordinates as the positive direction of the Y-axis, and the direction pointing to the center of the earth of the geodetic coordinates as the positive direction of the Z-axis. Moreover, the longitude and latitude coordinates can be converted into the XY plane of the geodetic coordinate system to determine the plane coordinates of the longitude and latitude coordinates in the XY plane. It can be understood that this XY plane is equivalent to a plane coordinate system. Among them, the origin of this plane coordinate system is a preset position. For example, the takeoff point of the aircraft can be used as the origin.

[0091] Due to the difference in coordinate systems, the longitude and latitude coordinates must be converted into the (X, Y) coordinates in the inertial coordinate system, and the conversion method is as follows formula (1):

[0092]

[0093] Among them, x and y are the converted (x, y) coordinate values respectively; lng and lat are the longitude and latitude coordinate values before conversion, and lng 0 and lat 0 are the longitude and latitude coordinate values of the origin respectively; R e is the equatorial radius of the earth, and R p is the polar radius of the earth. In the above formula (1), the cosine trigonometric function and the longitude and latitude are both converted into radian measure.

[0094] Step S102, determine the guidance distance of the aircraft according to the current speed; there is a positive correlation between the guidance distance and the current speed.

[0095] Since the dynamic response of the flapping-wing aircraft is not as fast as that of the rotorcraft and fixed-wing aircraft, during turning and ascending / descending, there is a certain time delay in the response during the process from the actuator action to the state change. The traditional trajectory tracking method cannot well adapt to the trajectory tracking of the flapping-wing aircraft, which will cause problems such as control response lag deviating from the trajectory or overshoot oscillation. In order to better perform trajectory tracking control on the flapping-wing aircraft, in this embodiment, based on a guidance algorithm with a certain prediction ability, the trajectory tracking of the aircraft is carried out, which can play a certain role in predictive control, so as to be able to make certain actions in advance to adjust according to the current state and target state of the aircraft.

[0096] The guidance algorithm, such as the L1 guidance algorithm, mainly draws on the proportional navigation method. A real-time moving reference point is selected on the target path, and this reference point is regarded as the target to be tracked at each moment. The aircraft is controlled to track this reference point. As the aircraft moves in pursuit, this reference point also moves on the target path through calculation until the aircraft reaches the end point of the target path. Among them, the guidance law is an algorithm used to guide the aircraft to the destination point or to meet the target. The principle of guidance is to calculate the relative position relationship between the aircraft's own state and the target's state, and then adjust itself to catch up with the target. Its relative motion equation is a set of differential equations describing the relative position relationship between the aircraft and the target. The proportional navigation method is a method that makes the rotational angular velocity of the velocity vector V of the aircraft proportional to the rotational angular velocity of the line of sight (the line of sight between the aircraft itself and the target).

[0097] In this embodiment, in order to select a suitable reference point from the target path, the expected distance between the aircraft and the reference point, that is, the guidance distance, is preset. Moreover, there is a positive correlation between this guidance distance and the current speed, that is, the greater the current speed of the aircraft, the greater this guidance distance, which can improve the control effect.

[0098] For example, there is a positive correlation between this guidance distance and the current speed. If the current speed is V, then this guidance distance L 1 can be expressed as: L 1 = K·V + B; where K is a preset proportionality coefficient, which can be determined based on the actual situation. For example, the value range of K can be in [3, 5], and the preset parameter B can be 0 or other constants.

[0099] Step S103, select a reference point on the target path of the aircraft; the reference distance between this reference point and the current position matches the guidance distance.

[0100] In this embodiment, the target path of the aircraft can be determined in advance; for example, the starting point and the end point of the target path can be determined, and then the target path between this starting point and the end point can be determined; among them, if the starting point and the end point of the target path are also in the form of longitude and latitude coordinates, they can be converted into XY coordinates based on the above formula (1) to be able to determine the expression of the target path in the plane coordinate system.

[0101] Moreover, after determining the current position of the aircraft and the current guidance distance L 1 then a suitable point can be selected from the target path as the reference point, and the reference distance between the reference point and the current position of the aircraft matches the guidance distance.

[0102] Among them, if there is a point on the target path whose distance from the current position is this guidance distance L 1If there is a point at a distance equal to the guidance distance L from the current position, this point can be used as the reference point, that is, the reference distance between the reference point and the current position is equal to the guidance distance L. 1 If there is no point on the target path at a distance equal to the guidance distance L from the current position, 1 then a point on the target path whose distance from the current position is greater than the guidance distance L 1 can be used as the corresponding reference point. For example, a point on the target path whose distance from the current position is the perpendicular distance can be used as the reference point, or other methods can be used to select the reference point. For example, a point on the target path whose distance from the current position is twice the guidance distance can be used as the reference point.

[0103] Step S104, determine the deflection angle between the reference line of sight and the current speed; the reference line of sight is the line of sight from the current position to the reference point.

[0104] In this embodiment, after selecting a suitable reference point, the line of sight from the current position of the aircraft to the reference point, that is, the reference line of sight, can be determined; moreover, the current speed of the aircraft has a certain direction, which is also the orientation of the aircraft. The angle between the reference line of sight and the current speed, that is, the deflection angle, can be determined.

[0105] Step S105, determine the centripetal acceleration for controlling the aircraft to move along the target path according to the current speed, reference distance, and deflection angle.

[0106] In this embodiment, after determining the current speed, reference distance, and deflection angle of the aircraft, the centripetal acceleration of the aircraft can be determined based on the guidance algorithm. This centripetal acceleration is specifically used to control the aircraft to move along the target path. This centripetal acceleration is generally perpendicular to the current speed of the aircraft, and it can specifically be the centripetal acceleration when the aircraft is planned to move in a circular motion. This centripetal acceleration has a positive relationship with the current speed and deflection angle, and a negative correlation with the reference distance.

[0107] Among them, the centripetal acceleration of the aircraft can be calculated based on the L1 guidance algorithm. Figure 2 Fig. shows a schematic diagram of calculating the centripetal acceleration based on the L1 guidance algorithm. Specifically, it is a top view, and the line connecting the aircraft and the reference point is the reference line of sight. And the centripetal acceleration satisfies the following formula (2):

[0108]

[0109] Among them, represents the centripetal acceleration, V represents the current speed of the aircraft, R represents the radius of the flight trajectory of the aircraft; L 0 represents the distance between the aircraft and the reference point, that is, the reference distance, Figure 2 In, the reference distance is taken as equal to the guidance distance as an example, that is, this reference distance L0 That is Figure 2 the guided distance L shown 1 ; η represents the deflection angle.

[0110] Step S106, control the turning of the aircraft according to the centripetal acceleration.

[0111] In this embodiment, after determining the centripetal acceleration of the aircraft, the turning control amount of the aircraft can be determined based on the centripetal acceleration, and then the turning of the aircraft can be controlled based on the turning control amount, such as controlling the yaw angle of the aircraft. Specifically, the calculated centripetal acceleration is used as the control amount of the turning attitude control algorithm, so that the turning mechanism of the aircraft moves reasonably according to the calculated centripetal acceleration, so that the aircraft can move as much as possible on the target path.

[0112] The trajectory tracking method provided in this embodiment determines a positively correlated guided distance based on the current speed of the aircraft, and then a reference point matching the guided distance can be selected from the target path. The centripetal acceleration of the aircraft can be determined by using a guided algorithm with predictive ability, so that the aircraft can be controlled to approach the pre-planned target path and perform trajectory tracking flight along the target path, and finally reach the specified position. The guided distance is positively correlated with the current speed, and a suitable reference point can be determined in real time based on the speed of the aircraft, and the trajectory tracking effect is better. When applied to a flapping-wing aircraft, it can realize the turning prediction of the flapping-wing aircraft, overcome the difficulties such as the response lag of the flapping-wing aircraft, and achieve an ideal satellite positioning and navigation trajectory tracking effect.

[0113] In this embodiment, another trajectory tracking method is provided, which can be applied to the controller of the aircraft, and the controller can be, for example, a single-chip microcomputer. Figure 3 is a flowchart of the trajectory tracking method according to an embodiment of the present invention, as Figure 3 shown, and the process includes the following steps.

[0114] Step S301, determine the current position and current speed of the aircraft.

[0115] For details, please refer to Figure 1 step S101 of the embodiment shown, which will not be elaborated here.

[0116] Step S302, determine the guided distance of the aircraft according to the current speed; the guided distance and the current speed are in a positive correlation relationship.

[0117] For details, please refer to Figure 1 step S102 of the embodiment shown, which will not be elaborated here.

[0118] Step S303: Select a reference point on the target path of the aircraft; the reference distance between the reference point and the current position matches the guidance distance.

[0119] Specifically, the above step S303 "Select a reference point on the target path of the aircraft" includes the following steps S3031 to S3033.

[0120] Step S3031: Determine the positional relationship between the reference circle and the target path; the reference circle is a circle with the current position as the center and the guidance distance as the radius.

[0121] In this embodiment, after determining the current position and the guidance distance of the aircraft, the corresponding reference circle can be determined based on this. The reference circle has the current position as the center and the guidance distance as the radius, that is, the radius of the reference circle is the guidance distance L. 1 。

[0122] Among them, the positional relationship between the reference circle and the target path can be specifically divided into intersection, tangency, and separation. Optionally, the above step S3031 "Determine the positional relationship between the reference circle and the target path" can specifically include steps A1 to A4.

[0123] Step A1: Determine the vertical distance between the current position and the target path.

[0124] Step A2: When the vertical distance is less than the guidance distance, the positional relationship between the reference circle and the target path is intersection.

[0125] Step A3: When the vertical distance is equal to the guidance distance, the positional relationship between the reference circle and the target path is tangency.

[0126] Step A4: When the vertical distance is greater than the guidance distance, the positional relationship between the reference circle and the target path is separation.

[0127] In this embodiment, the coordinates of the current position of the aircraft in the plane coordinate system can be determined. For example, it can be obtained based on the above formula (1); and based on the starting point and the ending point of the target path, the expression of the target path can be determined.

[0128] Specifically, let the coordinates of the current position of the aircraft be (x c , y c ), and the expression of the target path is y = kx + b, where k represents the slope of the target path and b represents the intercept of the target path. Based on this, the vertical distance d from the current position (x c , y c ) to the target path y = kx + b can be determined; and the vertical distance d is:

[0129] Among them, if the vertical distance d is less than the guidance distance L 1 , that is, d < L 1 , at this time, it can be determined that the reference circle intersects the target path, that is, the positional relationship between the two is intersection, and moreover, the two have two common points. Similarly, if the vertical distance d is equal to the guidance distance L 1 , that is, d = L 1 , at this time, it can be determined that the reference circle is tangent to the target path, that is, the positional relationship between the two is tangency, and moreover, the two have a unique common point, that is, the tangent point. If the vertical distance d is greater than the guidance distance L 1 , that is, d > L 1 , at this time, it can be determined that the reference circle is separated from the target path, that is, the positional relationship between the two is separation, and moreover, the two do not have a common point.

[0130] In this embodiment, by using the size relationship between the vertical distance d between the current position and the target path and the guidance distance L 1 , the positional relationship between the reference circle and the target path can be simply and conveniently determined.

[0131] Step S3032, in the case of intersection of the positional relationship, among the two common points between the reference circle and the target path, the common point closer to the end point of the target path is used as the reference point.

[0132] In this embodiment, if the positional relationship between the reference circle and the target path is intersection, then there are two common points between the two. And, in order to enable the aircraft to accurately track the reference point on the target path, among these two common points, the common point closer to the end point of the target path is selected as the reference point.

[0133] Figure 4 Shows a schematic diagram when the reference circle intersects the target path. As Figure 4 shown, the target path is a path from left to right, that is, its end point is on the right. For the two common points determined by the intersection of the reference circle and the target path, the common point on the right is the selected common point, that is, this common point is used as the subsequent reference point; while the common point on the left is the discarded common point, that is, this common point is discarded and not used subsequently.

[0134] If the expression of the target path is y = kx + b and the coordinates of the current position of the aircraft are (x c , y c ), then for the reference circle with this current position as the center and the guidance distance L1 as the radius, its expression is (x - x c ) 2 +(y - y c ) 2 = L 1 2 . Therefore, if taking (x r , yr ) represents the coordinates of the common point, and it satisfies the following formula (3):

[0135]

[0136] By solving the system of equations shown in the above formula (3), the coordinates (x r , y r ) of the common point can be obtained. Furthermore, the common point closer to the end point of the target path can be selected as the reference point, that is, the coordinates of the reference point can be determined.

[0137] For example, if (x r1 , y r1 ), (x r2 , y r2 ) respectively represent the coordinates of two common points, and let the end point of the target path be (x e , y e ), then the distances from the two common points to this end point are respectively:[[]]

[0138]

[0139] Furthermore, the common point closest to the target end point can be selected as the reference point. That is, if d 1 < d 2 , then the common point (x r1 , y r1 ) is closer to the end point, that is, the common point (x r1 , y r1 ) is selected as the reference point; if d 1 > d 2 , then the common point (x r2 , y r2 ) is closer to the end point, that is, the common point (x r2 , y r2 ) is selected as the reference point.

[0140] Step S3033, in the case of a tangential positional relationship, the tangent point between the reference circle and the target path is used as the reference point.

[0141] In this embodiment, if the positional relationship between the reference circle and the target path is tangential, then there is a unique common point between them, that is, the tangent point. At this time, the tangent point can be directly used as the reference point.

[0142] Figure 5 shows a schematic diagram when the reference circle is tangent to the target path. As Figure 5 shown, the target path is a path from left to right; if the reference circle is tangent to the target path, the unique tangent point can be used as the selected reference point.

[0143] It can be understood that when the reference circle intersects or is tangent to the target path, since the selected reference point is a point on the reference circle, the reference distance L between the reference point and the aircraft (i.e., the current position) 0 , is the same size as the preset guidance distance L 1 , that is Figure 4 and Figure 5 the guidance distance L shown in 1 , and can also be used to represent the reference distance L 0 .

[0144] Similarly, when the reference circle is tangent to the target path, a system of equations similar to the one shown in Equation (3) above can also be established to solve for the coordinates of the tangent point, which will not be elaborated here.

[0145] Optionally, after step S3031 "Determine the positional relationship between the reference circle and the target path", the above step S303 "Select a reference point on the target path of the aircraft" further includes the following step B1.

[0146] Step B1, in the case where the positional relationship is separation, take the foot of the perpendicular from the current position to the target path as the reference point.

[0147] In this embodiment, as shown above, the reference circle and the target path may also be separated, and there is no common point between them at this time; for example, when applying this method to a flapping-wing aircraft, due to the certain delay in the control response of the flapping-wing aircraft and being easily affected by gusts of wind, etc., it may cause the aircraft to deviate far from the target path at certain moments, thus resulting in the situation where the reference circle and the target path are separated.

[0148] In the case where the reference circle and the target path are separated, in this embodiment, draw a perpendicular line from the current position of the aircraft to the target path, and take the foot of the perpendicular from the current position to the target path as the reference point.

[0149] Figure 6 shows a schematic diagram when the reference circle and the target path are separated. As Figure 6 shown, the target path is a path from left to right; if the reference circle and the target path are separated, the foot of the perpendicular from the current position to the target path can be taken as the selected reference point. Correspondingly, the reference distance L 0 between the current position and the reference point is the perpendicular distance d from the current position to the target path.

[0150] In some alternative embodiments, the above step S303 "Select a reference point on the target path of the aircraft" further includes the following step C1.

[0151] Step C1, in the case where the positional relationship is intersection or tangency, determine the coordinates of the common point or the tangent point according to whether the target path is parallel to the coordinate axes.

[0152] In this embodiment, if the positional relationship is intersection or tangency, in order to quickly and accurately determine the coordinates of the reference point, that is, the coordinates of the common point or the tangent point, first determine whether the target path is parallel to the coordinate axes. Based on whether the target path is parallel to which coordinate axis (X-axis or Y-axis), or not parallel to the coordinate axes, different methods are respectively used to determine the coordinates of the reference point.

[0153] Among them, if the positional relationship is intersection, it can be divided into three cases: the target path is parallel to the X-axis, the target path is parallel to the Y-axis, and the target path is not parallel to any coordinate axis.

[0154] Specifically, in the case where the positional relationship is intersection, if the target path is parallel to the X-axis, the coordinates of the common point are as shown in the following formula (5):

[0155]

[0156] In the case where the positional relationship is intersection, if the target path is parallel to the Y-axis, the coordinates of the common point are as shown in the following formula (6):

[0157]

[0158] In this embodiment, if the target path is parallel to a certain coordinate axis, the coordinate value of the target path on the other coordinate axis is fixed, that is, the coordinate value of the common point (reference point) on the other coordinate axis is fixed. For example, if the target path is parallel to the X-axis, the coordinate value y of the common point on the Y-axis r is fixed, and it is the same as the coordinate value y of the starting point or the ending point of the target path on the Y-axis 0 , that is, y r =y 0 . And, since the distance from the common point to the current position (x c , y c ) is the guidance distance L 1 , based on this, the coordinate value x of the common point on the X-axis can be determined r , that is

[0159] It can be understood that based on the above formula (5), the coordinates of the two common points can be determined to be respectively Furthermore, the reference point can be selected from the two common points. The principle of formula (6) is similar to that of formula (5), and will not be elaborated here.

[0160] In addition, in the case where the positional relationship is intersection, if the target path is not parallel to the coordinate axes, based on the system of equations shown in the above formula (3), the coordinates of the common point can be obtained as shown in the following formula (7):

[0161]

[0162] Similarly, based on the above formulas (5) to (7), the coordinates of the common point with a tangential positional relationship, i.e., the coordinates of the tangent point, can be further determined.

[0163] Specifically, in the case where the positional relationship is tangency, if the target path is parallel to the X-axis, the coordinates of the tangent point are given by the following formula (8):

[0164]

[0165] In the case where the positional relationship is tangency, if the target path is parallel to the Y-axis, the coordinates of the tangent point are given by the following formula (9):

[0166]

[0167] In the case where the positional relationship is tangency, if the target path is not parallel to the coordinate axes, the coordinates of the tangent point are given by the following formula (10):

[0168]

[0169] Among them, (x r , y r ) represents the coordinates of the common point, (x t , y t ) represents the coordinates of the tangent point, (x c , y c ) represents the coordinates of the current position, (x 0 , y 0 ) represents the coordinates of the starting point or ending point of the target path, K 1 represents the guidance distance, l represents the slope of the target path, and b represents the intercept of the target path.

[0170] It can be understood that in the case where the positional relationship is tangency, the coordinates (x t , y t ) of the tangent point are also the coordinates of the reference point.

[0171] In addition, optionally, the above step S303 "select a reference point on the target path of the aircraft" further includes the following step C2.

[0172] Step C2, in the case where the positional relationship is separation, determine the coordinates of the common point or the tangent point according to whether the target path is parallel to the coordinate axes.

[0173] In this embodiment, similar to the cases where the positional relationship is intersection or tangency, in the case where the positional relationship is separation, first determine whether the target path is parallel to the coordinate axes, and based on whether the target path is parallel to which coordinate axis (X-axis or Y-axis), or not parallel to the coordinate axes, different methods are respectively used to determine the coordinates of the reference point, i.e., the coordinates of the perpendicular point.

[0174] Moreover, when the positional relationship is separated, it can be specifically divided into three cases: the target path is parallel to the X-axis, the target path is parallel to the Y-axis, and the target path is not parallel to any coordinate axis.

[0175] Among them, when the positional relationship is separated, if the target path is parallel to the X-axis, the coordinates of the perpendicular point are given by the following formula (11):

[0176]

[0177] When the positional relationship is separated, if the target path is parallel to the Y-axis, the coordinates of the perpendicular point are given by the following formula (12):

[0178]

[0179] When the positional relationship is separated, if the target path is not parallel to the coordinate axis, the coordinates of the perpendicular point are given by the following formula (13):

[0180]

[0181] Among them, (x v , y v ) represents the coordinates of the perpendicular point, (x c , y c ) represents the coordinates of the current position, (x 0 , y 0 ) represents the coordinates of the starting point or the ending point of the target path, k represents the slope of the target path, and b represents the intercept of the target path.

[0182] It can be understood that when the positional relationship is separated, the coordinates (x v , y v ) of the perpendicular point are also the coordinates of the reference point.

[0183] In this embodiment, by determining whether the target path is parallel to the coordinate axis, it can be divided into three cases, and then the reference point coordinates are calculated respectively based on different cases, which can quickly and accurately complete the calculation.

[0184] Step S304, determining the deflection angle between the reference line of sight and the current speed; the reference line of sight is the line of sight from the current position to the reference point.

[0185] For details, please refer to Figure 1 Step S104 of the illustrated embodiment, which will not be elaborated here.

[0186] In some alternative embodiments, the calculated reference point coordinates can be used to determine the deflection angle between the reference line of sight and the current speed. Specifically, the above step S304 "determining the deflection angle between the reference line of sight and the current speed" may include the following steps D1 to D2.

[0187] Step D1, determine the line-of-sight angle between the reference line-of-sight and the reference line, and determine the speed angle between the current speed and the reference line.

[0188] Step D2, use the difference between the line-of-sight angle and the speed angle as the deflection angle between the reference line-of-sight and the current speed.

[0189] In this embodiment, to facilitate the unified determination of the deflection angle η, a reference line for representing the angle is preset. For example, the due north direction can be used as the reference line.

[0190] Specifically, when determining the reference line-of-sight between the current position (x c , y c ) and the reference point (x p , y p ), the included angle between the reference line-of-sight and the reference line can be determined, and this included angle is used as the line-of-sight angle q. Moreover, the included angle between the current speed V and the reference line can also be determined, and this included angle is used as the speed angle σ.

[0191] Since both the line-of-sight angle q and the speed angle σ are included angles determined with the reference line as the reference, the difference between the line-of-sight angle q and the speed angle σ is the deflection angle η between the reference line-of-sight and the current speed that is independent of the reference line, that is: η = q - σ.

[0192] Optionally, the X-axis of the coordinate system can be used as the reference line, and then the line-of-sight angle q and the speed angle σ can be calculated.

[0193] Specifically, the line-of-sight angle q can be obtained through the inclination angle of the straight line formed by the current position coordinate point and the real-time reference point; and its value range is set to [0, 2π), and this line-of-sight angle q is:

[0194] And,

[0195] Similarly, the speed angle σ can be obtained through the inclination angle of the straight line formed by the current position coordinate point and the historical position coordinate point of the previous moment; and its value range is set to [0, 2π), and this speed angle σ is:

[0196] And,

[0197] Wherein, q represents the line-of-sight angle, σ represents the speed angle, (x p , y p ) represents the coordinates of the reference point, (x c , y c ) represents the coordinates of the current position, (x c0 , y c0)Coordinates representing the historical positions of the aircraft when moving along the target path, which can specifically be the position coordinates at the previous moment.

[0198] It can be understood that for the inverse trigonometric function arctan(), when the denominator therein is 0, its value is related to the sign of the numerator. Taking as an example, at x p = x c , if y p > y c , then If y p < y c , then

[0199] In this embodiment, by setting a reference line, the line-of-sight angle and the velocity angle are determined, and then the difference between the two can be conveniently used as the deflection angle between the reference line of sight and the current velocity. Based on this, the deflection angle can be determined in a unified manner and can be applied to various target paths.

[0200] Step S305: Determine the centripetal acceleration for controlling the aircraft to move along the target path according to the current velocity, the reference distance, and the deflection angle.

[0201] For details, please refer to Figure 1 Step S105 of the embodiment shown, which will not be elaborated here.

[0202] In this embodiment, the centripetal acceleration can be calculated based on the above formula (2).

[0203] Figure 7 Shows a schematic diagram of real-time calculation of centripetal acceleration. As Figure 7 shown, the trajectory that the aircraft needs to track includes a takeoff point and multiple target points. Based on these target points, the trajectory can be divided into multiple target paths; for example, the first target path is between the takeoff point and the first target point, the second target path is between the first target point and the second target point, and so on. And, at the current moment, the latitude and longitude of the aircraft's position can be determined in real time. Through coordinate transformation as shown in the above formula (1) and the like, the respective coordinates in the plane coordinate system can be determined, including the current real-time position X-Y coordinates (x c , y c ), as well as the X-Y coordinates of each target point, and then a target path in the form of a straight line can be generated.

[0204] And, based on the real-time flight speed V of the aircraft (i.e., the current speed), a guidance distance L 1 is set, and then a reference circle can be generated in real time. Through the positional relationship between the reference circle and the target path, the appropriate reference point X-Y coordinates (x p , yp )。

[0205] Based on the current real-time position X-Y coordinates (x c , y c ) and the reference point X-Y coordinates (x p , y p ), the line-of-sight angle q between the reference line of sight and the reference line can be determined; and, based on the current real-time position X-Y coordinates (x c , y c ) and the X-Y coordinates (x c0 , y c0 ) of the aircraft at the previous moment, the corresponding speed angle σ can be determined, and then the deflection angle η can be calculated.

[0206] And, the reference distance L 0 can be determined. Among them, when the positional relationship is intersection or tangency, L 0 = L 1 ; when the positional relationship is separation, the reference distance L 0 is the perpendicular distance d from the current position to the target path.

[0207] After determining the speed V, the deflection angle η, and the reference distance L 0 , the acceleration for controlling the turning of the aircraft can be calculated based on the above formula (2)

[0208] Step S306, control the turning of the aircraft according to the centripetal acceleration.

[0209] For details, please refer to Figure 1 Step S106 of the embodiment shown, which will not be elaborated here.

[0210] The trajectory tracking method provided in this embodiment, by real-time monitoring the relative position state of the aircraft body and the target trajectory, and then adopting different strategies to select the reference point, calculates the required control amount, controls the aircraft to approach the trajectory, and realizes fast, accurate and stable flight along the trajectory, which can effectively overcome difficulties such as the response lag of the aircraft; even if there is a time interval in satellite positioning, the aircraft can autonomously perform trajectory tracking flight according to the pre-planned satellite positioning path, achieving an ideal satellite positioning and navigation trajectory tracking effect.

[0211] This embodiment also provides a flapping-wing aircraft, which includes: a body, a controller, and an actuator controlled by the controller; the controller is used to execute the trajectory tracking method provided in any of the above embodiments.

[0212] In this embodiment, the airframe of the flapping-wing aircraft may specifically include mechanical structures such as wings and tail fins, and the actuators may specifically include motors, servos, etc. The actuators drive the mechanical structures to move, enabling the flapping-wing aircraft to complete the required flight tasks.

[0213] For example, the actuator structure includes a steering servo located on the tail fin. Based on the steering control amount determined by the controller, the steering servo can be controlled. Among them, the steering is achieved by the action of the steering servo driving the steering vane to generate a change in air flow, and the directionality of the steering control amount output by the controller determines the direction of left and right steering.

[0214] In this embodiment, a trajectory tracking device is also provided. This device is used to implement the above embodiments and preferred implementation manners, and those that have been described will not be repeated. As used hereinafter, the term "module" may be a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation in hardware, or a combination of software and hardware is also possible and contemplated.

[0215] This embodiment provides a trajectory tracking device, as Figure 8 shown, including:

[0216] A parameter determination module 801, configured to determine the current position and current speed of the aircraft;

[0217] A distance setting module 802, configured to determine the guidance distance of the aircraft according to the current speed; there is a positive correlation between the guidance distance and the current speed;

[0218] A processing module 803, configured to select a reference point on the target path of the aircraft; the reference distance between the reference point and the current position matches the guidance distance; determine the deflection angle between the reference line of sight and the current speed; the reference line of sight is the line of sight from the current position to the reference point; determine the centripetal acceleration for controlling the aircraft to move along the target path according to the current speed, the reference distance, and the deflection angle;

[0219] A control module 804, configured to control the steering of the aircraft according to the centripetal acceleration.

[0220] In some alternative implementation manners, the processing module 803 selecting a reference point on the target path of the aircraft includes:

[0221] Determine the positional relationship between the reference circle and the target path; the reference circle is a circle with the current position as the center and the guidance distance as the radius;

[0222] When the positional relationship is intersection, among the two common points between the reference circle and the target path, the common point closer to the end point of the target path is used as the reference point;

[0223] When the positional relationship is tangency, the tangent point between the reference circle and the target path is used as the reference point.

[0224] In some alternative embodiments, when the processing module 803 selects a reference point on the target path of the aircraft, it further includes:

[0225] When the positional relationship is intersection or tangency, according to whether the target path is parallel to the coordinate axes, the coordinates of the common point or the tangent point are determined;

[0226] Among them, when the positional relationship is intersection, if the target path is parallel to the X-axis, the coordinates of the common point are:

[0227]

[0228] If the target path is parallel to the Y-axis, the coordinates of the common point are:

[0229]

[0230] If the target path is not parallel to the coordinate axes, the coordinates of the common point are:

[0231]

[0232] When the positional relationship is tangency, if the target path is parallel to the X-axis, the coordinates of the tangent point are:

[0233]

[0234] If the target path is parallel to the Y-axis, the coordinates of the tangent point are:

[0235]

[0236] If the target path is not parallel to the coordinate axes, the coordinates of the tangent point are:

[0237]

[0238] Among them, (x r , y r ) represents the coordinates of the common point, (x t , y t ) represents the coordinates of the tangent point, (x c , y c ) represents the coordinates of the current position, (x0 , y 0 ) represents the coordinates of the starting or ending point of the target path, L 1 represents the guidance distance, k represents the slope of the target path, and b represents the intercept of the target path.

[0239] In some alternative embodiments, when the processing module 803 selects a reference point on the target path of the aircraft, it further includes:

[0240] When the positional relationship is separation, taking the perpendicular point from the current position to the target path as the reference point.

[0241] In some alternative embodiments, when the processing module 803 selects a reference point on the target path of the aircraft, it further includes:

[0242] When the positional relationship is separation, determining the coordinates of the common point or the tangent point according to whether the target path is parallel to the coordinate axes;

[0243] Among them, when the positional relationship is separation, if the target path is parallel to the X-axis, the coordinates of the perpendicular point are:

[0244]

[0245] If the target path is parallel to the Y-axis, the coordinates of the perpendicular point are:

[0246]

[0247] If the target path is not parallel to the coordinate axes, the coordinates of the perpendicular point are:

[0248]

[0249] Among them, (x v , y v ) represents the coordinates of the perpendicular point, (x c , y c ) represents the coordinates of the current position, (x 0 , y 0 ) represents the coordinates of the starting or ending point of the target path, k represents the slope of the target path, and b represents the intercept of the target path.

[0250] In some alternative embodiments, when the processing module 803 determines the positional relationship between the reference circle and the target path, it includes:

[0251] Determining the perpendicular distance between the current position and the target path;

[0252] When the vertical distance is less than the guidance distance, the positional relationship between the reference circle and the target path is intersection;

[0253] When the vertical distance is equal to the guidance distance, the positional relationship between the reference circle and the target path is tangency;

[0254] When the vertical distance is greater than the guidance distance, the positional relationship between the reference circle and the target path is separation.

[0255] In some alternative embodiments, the processing module 803 determines the deflection angle between the reference line of sight and the current speed, including:

[0256] Determining the line-of-sight angle between the reference line of sight and the reference line, and determining the speed angle between the current speed and the reference line;

[0257] Taking the difference between the line-of-sight angle and the speed angle as the deflection angle between the reference line of sight and the current speed.

[0258] In some alternative embodiments, the line-of-sight angle is:

[0259] And,

[0260] The speed angle is:

[0261] And,

[0262] Wherein, q represents the line-of-sight angle, σ represents the speed angle, (x p , y p ) represents the coordinates of the reference point, (x c , y c ) represents the coordinates of the current position, (x c0 , y c0 ) represents the coordinates of the historical position when the aircraft moves along the target path.

[0263] The further function descriptions of the above-mentioned various modules and units are the same as those in the corresponding above-mentioned embodiments, and will not be elaborated here.

[0264] The trajectory tracking device in this embodiment is presented in the form of functional units. Here, the unit refers to an ASIC (Application Specific Integrated Circuit) circuit, including a processor and a memory that execute one or more software or fixed programs, and / or other devices that can provide the above functions.

[0265] An embodiment of the present invention further provides a computer device having the above-mentioned Figure 8 trajectory tracking device shown.

[0266] Please refer to Figure 9 , Figure 9 which is a schematic structural diagram of a computer device provided by an optional embodiment of the present invention. As Figure 9 shown, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including a high-speed interface and a low-speed interface. Each component communicates with each other using different buses and can be installed on a common motherboard or installed in other ways as needed. The processor can process instructions executed within the computer device, including instructions stored in the memory or on the memory to display graphical information of the GUI on an external input / output device (such as a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a set of blade servers, or a multi-processor system). Figure 9 In

[0267] FIG. 10, one processor 10 is taken as an example.

[0268] The processor 10 may be a central processing unit, a network processor, or a combination thereof. Among them, the processor 10 may further include a hardware chip. The above-mentioned hardware chip may be an application-specific integrated circuit, a programmable logic device, or a combination thereof. The above-mentioned programmable logic device may be a complex programmable logic device, a field programmable gate array, a general array logic, or any combination thereof.

[0268] Among them, the memory 20 stores instructions executable by at least one processor 10, so that the at least one processor 10 executes the method shown in the above embodiment.

[0269] The memory 20 may include a storage program area and a storage data area. Among them, the storage program area may store an operating system and application programs required for at least one function; the storage data area may store data created according to the use of the computer device. In addition, the memory 20 may include a high-speed random access memory and may also include a non-transitory memory, such as at least one disk storage device, a flash memory device, or other non-transitory solid-state storage devices. In some optional embodiments, the memory 20 may optionally include a memory remotely set relative to the processor 10, and these remote memories may be connected to the computer device through a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an enterprise intranet, a local area network, a mobile communication network, and a combination thereof.

[0270] The memory 20 may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk or solid state drive; the memory 20 may further include a combination of the above types of memory.

[0271] The computer device further includes a communication interface 30 for the computer device to communicate with other devices or communication networks.

[0272] The embodiments of the present invention also provide a computer-readable storage medium. The methods according to the embodiments of the present invention can be implemented in hardware, firmware, or be implemented as computer code that can be recorded on a storage medium, or be implemented as computer code that is originally stored in a remote storage medium or a non-transitory machine-readable storage medium and downloaded through a network and will be stored in a local storage medium, so that the methods described herein can be stored in such software processes on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only memory, a random access memory, a flash memory, a hard disk, or a solid state drive, etc.; further, the storage medium can also include a combination of the above types of memory. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code, and when the software or computer code is accessed and executed by the computer, the processor, or the hardware, the methods shown in the above embodiments are implemented.

[0273] A part of the present invention can be applied as a computer program product, such as computer program instructions, which when executed by a computer, can call or provide the methods and / or technical solutions according to the present invention through the operation of the computer. Those skilled in the art should be able to understand that the forms of existence of computer program instructions in a computer-readable medium include, but are not limited to, source files, executable files, installation package files, etc. Correspondingly, the ways for computer program instructions to be executed by a computer include, but are not limited to: the computer directly executes the instructions, or the computer compiles the instructions and then executes the corresponding compiled program, or the computer reads and executes the instructions, or the computer reads and installs the instructions and then executes the corresponding installed program. Herein, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible by the computer.

[0274] Although the embodiments of the present invention are described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations should all be covered within the protection scope of the present invention.

Claims

1. A trajectory tracking method, characterized in that: The method comprises: Determine the current position and current speed of the aircraft; Determining a guidance distance of the aircraft according to the current speed; there is a positive correlation between the guidance distance and the current speed; A reference point is selected on the target path of the aircraft; a reference distance between the reference point and the current position is matched with the guidance distance; Determine a deflection angle between a reference sight line and the current speed; the reference sight line is a sight line between the current position and the reference point; determining a centripetal acceleration for controlling the aircraft to move along the target path according to the current speed, the reference distance and the deflection angle; The turning of the aircraft is controlled according to the centripetal acceleration.

2. The method according to claim 1, characterized in that: The selecting a reference point on the target path of the aircraft comprises: Determine the positional relationship between a reference circle and the target path; the reference circle is a circle with the current position as the center and the guidance distance as the radius; In the case where the positional relationship is an intersection, the common point between the reference circle and the target path, whichever is closer to the end point of the target path, is used as a reference point; In the case where the positional relationship is tangent, the tangent point between the reference circle and the target path is used as a reference point.

3. The method according to claim 2, characterized in that The selecting of a reference point on the target path of the aircraft further includes: In the case where the positional relationship is an intersection or a tangency, determining the coordinates of the common point or the tangency point according to whether the target path is parallel to the coordinate axis; Wherein, in the case where the positional relationship is an intersection, if the target path is parallel to the X-axis, the coordinates of the common point are: If the target path is parallel to the Y axis, the coordinates of the common point are: If the target path is not parallel to the coordinate axis, the coordinates of the common point are: In the case where the positional relationship is tangent, if the target path is parallel to the X-axis, the coordinates of the tangent point are: If the target path is parallel to the Y axis, the coordinates of the tangent point are: If the target path is not parallel to the coordinate axis, the coordinates of the tangent point are: Among them, (x r ,y r ) represents the coordinates of the common point, (x t ,y t ) represents the coordinates of the tangent point, (x c ,y c ) represents the coordinates of the current position, (x0, y0) represents the coordinates of the starting point or end point of the target path, L1 represents the guidance distance, k represents the slope of the target path, and b represents the intercept of the target path.

4. The method according to claim 2, characterized in that: The selecting of a reference point on the target path of the aircraft further includes: When the positional relationship is separated, the vertical point from the current position to the target path is used as a reference point.

5. The method according to claim 4, characterized in that The selecting of a reference point on the target path of the aircraft further includes: In the case where the positional relationship is separated, determining the coordinates of the common point or the tangent point according to whether the target path is parallel to the coordinate axis; Wherein, in the case where the positional relationship is separated, if the target path is parallel to the X-axis, the coordinates of the vertical point are: If the target path is parallel to the Y axis, the coordinates of the vertical point are: If the target path is not parallel to the coordinate axis, the coordinates of the vertical point are: Among them, (x v ,y v ) represents the coordinates of the vertical point, (x c ,y c ) represents the coordinates of the current position, (x0, y0) represents the coordinates of the starting point or end point of the target path, k represents the slope of the target path, and b represents the intercept of the target path.

6. The method according to any one of claims 2 to 5, characterized in that The determining the positional relationship between the reference circle and the target path includes: determining a vertical distance between the current position and the target path; When the vertical distance is less than the guidance distance, the positional relationship between the reference circle and the target path is an intersection; When the vertical distance is equal to the guidance distance, the positional relationship between the reference circle and the target path is tangent; When the vertical distance is greater than the guidance distance, the positional relationship between the reference circle and the target path is separation.

7. The method according to claim 1, characterized in that The determining of the deflection angle between the reference line of sight and the current speed comprises: Determining a sight angle between a reference sight line and a baseline, and determining a velocity angle between the current velocity and the baseline; The difference between the sight line angle and the speed angle is used as the deflection angle between the reference sight line and the current speed.

8. The method according to claim 7, characterized in that The sight angle is: and, The velocity angle is: and, Wherein, q represents the sight angle, σ represents the velocity angle, (x p ,y p ) represents the coordinates of the reference point, (x c ,y c ) represents the coordinates of the current position, (x c0 ,y c0 ) represents the coordinates of the historical position of the aircraft when it moves along the target path.

9. A trajectory tracking device, characterized in that: The device comprises: A parameter determination module is used to determine the current position and current speed of the aircraft; A distance setting module, used to determine the guidance distance of the aircraft according to the current speed; there is a positive correlation between the guidance distance and the current speed; A processing module, configured to select a reference point on the target path of the aircraft; a reference distance between the reference point and the current position is matched with the guidance distance; a deflection angle between a reference line of sight and the current speed is determined; the reference line of sight is a line of sight between the current position and the reference point; and a centripetal acceleration for controlling the aircraft to move along the target path is determined according to the current speed, the reference distance and the deflection angle; A control module is used to control the steering of the aircraft according to the centripetal acceleration.

10. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the trajectory tracking method according to any one of claims 1 to 8 by executing the computer instructions.

11. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the trajectory tracking method according to any one of claims 1 to 8.

12. A flapping-wing aircraft, characterized in that: include: A machine body, a controller and an actuator controlled by the controller; The controller is used to execute the trajectory tracking method according to any one of claims 1 to 8.

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