Attitude control method and device of unmanned aerial vehicle, electronic equipment and storage medium
By constructing the attitude control equations and state space equations of the UAV, and combining the attitude observer and feedforward compensation strategy, the attitude control error problem of the inclined propeller vertical take-off and landing fixed-wing UAV was solved, and precise flight attitude control and stability improvement were achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHANGHAI AIRCRAFT MFG
- Filing Date
- 2026-03-06
- Publication Date
- 2026-06-05
AI Technical Summary
In existing technologies, the attitude control results of vertical take-off and landing fixed-wing UAVs with inclined propellers have large errors and cannot achieve precise control.
By constructing the attitude control equations of the UAV, obtaining the state space equations, and adjusting the rotational speed of the skewed propellers according to the real-time rotational speed of the propellers and the desired flight attitude, combined with the attitude observer and feedforward compensation strategy, precise attitude control of the UAV is achieved.
It achieves precise attitude control of vertical take-off and landing fixed-wing UAVs with inclined propellers, improving flight stability and attitude accuracy.
Smart Images
Figure CN122151916A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of unmanned aerial vehicle (UAV) control technology, and in particular to an attitude control method, device, electronic device, and storage medium for a UAV. Background Technology
[0002] Vertical takeoff and landing (VTOL) fixed-wing unmanned aerial vehicles (UAVs) are a type of UAV capable of vertical takeoff, hovering, and landing. They typically have independent propulsion and vertical takeoff power units. Because they combine the vertical takeoff and landing capabilities of helicopters with the long-range advantages of fixed-wing aircraft, they have become an important design structure in the field of UAVs.
[0003] In the existing technology, traditional vertical take-off and landing fixed-wing UAVs are equipped with vertical thrusters. When taking off vertically, the vertical thrusters do not work, resulting in a waste of structure and weight and affecting cruise performance. Therefore, vertical take-off and landing fixed-wing UAVs with slanted propellers have come into view. For this type of UAV, the longitudinal lift from the propeller thrust is usually incorporated into the wing lift, and the attitude control method of traditional vertical take-off and landing fixed-wing UAVs is used.
[0004] However, for vertical takeoff and landing fixed-wing UAVs with slanted propellers, the control process is more complex than that of traditional vertical takeoff and landing fixed-wing UAVs because the propeller thrust also generates pitch aerodynamic torque. Therefore, using the attitude control method of traditional vertical takeoff and landing fixed-wing UAVs often leads to large deviations in attitude control results, making it impossible to achieve precise control of the UAV. Summary of the Invention
[0005] This invention provides an attitude control method, device, electronic device, and storage medium for unmanned aerial vehicles (UAVs) to solve the problem of large errors in the attitude control results of vertical take-off and landing fixed-wing UAVs.
[0006] According to another aspect of the present invention, an attitude control method for an unmanned aerial vehicle (UAV) is provided, comprising: The attitude control equations of the UAV are obtained based on its attitude angular velocity, moment of inertia, net external torque, and rotational angular velocity tensor; wherein the UAV is equipped with multiple obliquely mounted propellers. Based on the resultant external force equation, resultant external torque equation, power distribution equation, center of mass motion equation, and attitude control equation of the UAV, the state space equation of the UAV is obtained; wherein, the power distribution equation represents the relationship between the resultant external force and resultant external torque of the UAV propeller and the rotational speed of each of the inclined propellers. The actual flight attitude of the UAV is obtained based on the state-space equation of the UAV and the real-time rotation speed of each of the inclined propellers, or the adjustment speed of each of the inclined propellers is obtained based on the state-space equation of the UAV and the desired flight attitude of the UAV.
[0007] The attitude control method for the UAV further includes: obtaining the vertical takeoff equation of the UAV based on the resultant external force of the UAV's propeller, the resultant external torque of the propeller, and the force helix vector; and obtaining the vertical takeoff speed of each of the inclined propellers based on the vertical takeoff equation of the UAV and the desired force helix vector of the UAV.
[0008] The step of obtaining the vertical takeoff speed of each of the inclined propellers based on the vertical takeoff equation of the UAV and the desired force helical vector of the UAV includes: if it is determined that the number of propellers of the UAV is greater than six, obtaining the target functional of the UAV based on the vertical takeoff equation, the power distribution equation and the total energy consumption of the motors of each of the inclined propellers; and obtaining the vertical takeoff speed of each of the inclined propellers based on the target functional.
[0009] After obtaining the state-space equation of the UAV based on the resultant external force equation, resultant external torque equation, power distribution equation, center of mass motion equation, and attitude control equation, the method further includes: obtaining the attitude observer of the UAV; obtaining the transfer matrix identification equation of the UAV based on the attitude observer and the state-space equation; obtaining the transfer matrix based on the transfer matrix identification equation; and obtaining the level flight speed of each of the inclined propellers based on the transfer matrix.
[0010] The attitude control method for the UAV further includes: obtaining the maximum control torque of the canard control surface of the UAV and comparing the maximum control torque with the thrust pitch torque of each of the slanted propellers; if it is determined that the maximum control torque is greater than or equal to the thrust pitch torque, obtaining a feedforward compensation equation based on the deflection angle of the canard control surface and the rotational speed of each of the slanted propellers; and obtaining the feedforward compensation angle of the canard control surface based on the feedforward compensation equation and the real-time rotational speed of each of the slanted propellers.
[0011] After comparing the maximum control torque with the thrust pitch torque of each of the skewed propellers, the method further includes: if it is determined that the maximum control torque is less than the thrust pitch torque, obtaining the feedforward compensation angle of the canard control surface according to the feedforward compensation equation, the real-time rotational speed of each of the skewed propellers and the relaxation factor, and obtaining the feedforward compensation rotational speed of each of the skewed propellers according to the rotational speed of each of the skewed propellers and the relaxation factor.
[0012] According to another aspect of the present invention, an attitude control device for a drone is provided, comprising: The attitude equation acquisition module is used to acquire the attitude control equation of the UAV based on the UAV's attitude angular velocity, moment of inertia, net external torque, and rotational angular velocity tensor; wherein the UAV is equipped with multiple obliquely mounted propellers; The state equation acquisition module is used to acquire the state space equation of the UAV based on the resultant external force equation, resultant external torque equation, power distribution equation, center of mass motion equation and attitude control equation of the UAV; wherein, the power distribution equation represents the relationship between the resultant external force and resultant external torque of the UAV propeller and the rotational speed of each of the inclined propellers. The flight attitude acquisition module is used to acquire the actual flight attitude of the UAV based on the UAV's state space equation and the real-time rotation speed of each of the inclined propellers, or to acquire the adjustment speed of each of the inclined propellers based on the UAV's state space equation and the UAV's desired flight attitude.
[0013] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the attitude control method of a UAV according to any embodiment of the present invention.
[0014] According to another aspect of the present invention, a computer-readable storage medium is provided, the computer-readable storage medium storing computer instructions for causing a processor to execute and implement the attitude control method of the unmanned aerial vehicle according to any embodiment of the present invention.
[0015] According to another aspect of the present invention, a computer program product is provided, comprising a computer program that, when executed by a processor, implements the attitude control method for a UAV as described in any embodiment of the present invention.
[0016] The technical solution of this invention obtains the attitude control equations of the UAV based on its attitude angular velocity, moment of inertia, net external torque, and angular velocity tensor; it obtains the state-space equations of the UAV based on the net external force equations, net external torque equations, power distribution equations, center of mass motion equations, and attitude control equations; and it obtains the actual flight attitude of the UAV based on the state-space equations and the real-time rotational speeds of each slanted propeller. Thus, by constructing the state-space equations of the UAV, the actual flight attitude of the UAV can be obtained based on the real-time rotational speeds of each slanted propeller, thereby achieving the detection and acquisition of the UAV's flight attitude. Simultaneously, based on the state-space equations of the UAV and the desired flight attitude of the UAV, the adjustment speeds of each slanted propeller are obtained, thereby achieving accurate control of the UAV's flight attitude.
[0017] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description
[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0019] Figure 1 This is a flowchart of an attitude control method for an unmanned aerial vehicle (UAV) according to Embodiment 1 of the present invention; Figure 2 This is a flowchart of another attitude control method for a UAV provided according to Embodiment 2 of the present invention; Figure 3 This is a flowchart of another attitude control method for a UAV provided according to Embodiment 3 of the present invention; Figure 4 This is a flowchart of another attitude control method for a UAV provided according to Embodiment 4 of the present invention; Figure 5 This is a schematic diagram of the attitude control device for an unmanned aerial vehicle (UAV) according to Embodiment 5 of the present invention; Figure 6 This is a schematic diagram of the structure of an electronic device that implements the attitude control method for a drone according to an embodiment of the present invention. Detailed Implementation
[0020] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.
[0021] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.
[0022] Example 1 Figure 1 This is a flowchart of an attitude control method for a drone provided in Embodiment 1 of the present invention. This embodiment is applicable to situations where drone attitude control and monitoring are completed based on the drone's state-space equations. This method can be executed by the drone's attitude control device, which can be implemented in hardware and / or software. The drone's attitude control device can be configured in an electronic device, which is configured within the drone's flight control system. Figure 1 As shown, the method includes: S101. Obtain the attitude control equation of the UAV based on its attitude angular velocity, moment of inertia, net external torque, and rotational angular velocity tensor; wherein the UAV is equipped with multiple obliquely mounted propellers.
[0023] The drone in this embodiment of the invention may specifically include a vertical takeoff and landing fixed-wing drone equipped with a fixed angled propeller; wherein, vertical takeoff and landing means that the drone can take off, hover, and land vertically like a helicopter; fixed wing means that lift is generated by a fixed wing; angled propeller means that the rotation axis of the propeller is tilted at an angle to both the ground and the fuselage, that is, neither perpendicular to the ground nor parallel to the fuselage, so that the propeller can provide both vertical lift and horizontal thrust simultaneously; fixed means that the angled propeller has a fixed angle, rather than a tiltable angle; optionally, in this embodiment of the invention, the tilt angle of the angled propeller is not specifically limited.
[0024] Because the UAV's propellers are installed at an angle, the axial thrust generated by the propellers is not parallel to the aircraft's axis. Therefore, this thrust can be decomposed into longitudinal lift and forward thrust, thus achieving the effect of oblique propulsion. Simultaneously, the propeller thrust also generates pitching aerodynamic torque. In this embodiment of the invention, the forward flight direction of the UAV is defined as the horizontal direction. That is, the roll axis direction; the longitudinal lift direction of the aircraft is defined as the vertical direction. That is, the yaw axis direction; perpendicular to the horizontal direction. and vertical direction The direction is defined as the vertical direction. That is, the direction of the pitch axis.
[0025] Attitude angular velocity The Euler angle change rate of the UAV is described, including the roll rate. Pitch angular velocity and yaw rate It indicates that the drones circled around axis, axis, Instantaneous rotational rate of the axis; rotational angular velocity tensor It is a three-dimensional antisymmetric tensor describing the rotational state of the UAV, based on the UAV's roll rate. Pitch angular velocity and yaw rate The rotational angular velocity tensor can be directly constructed. Its manifestation is as follows: (Formula 1); rotational inertia matrix It is a symmetric matrix used to describe the inertial distribution of a UAV rotating around different axes. The main diagonal elements represent the principal moments of inertia about each axis, and the off-diagonal elements are the product of inertia, reflecting the asymmetry of the mass distribution. This is the moment of inertia matrix in this embodiment of the invention. It can be represented in the following form: (Formula 2); in, These represent the drones orbiting... axis, axis, Moment of inertia of the shaft; Indicates drones circling When the shaft rotates The coupling effect of axial motion; the rotational inertia matrix of the UAV can be obtained using existing modeling software. .
[0026] Therefore, the aircraft's attitude control equations can be expressed in the following form: (Formula 3); in, The net external torque acting on the UAV is the vector summation of various external torques acting on the UAV; due to the attitude angular velocity It is a time function, therefore Indicates attitude angular velocity Differentiation is performed; the attitude control equations reflect the net external torque and roll rate of the UAV. Pitch angular velocity and yaw rate The relationships between them.
[0027] S102. Based on the resultant external force equation, resultant external torque equation, power distribution equation, center of mass motion equation, and attitude control equation of the UAV, obtain the state space equation of the UAV; wherein, the power distribution equation represents the relationship between the resultant external force and resultant external torque of the UAV propeller and the rotational speed of each of the inclined propellers.
[0028] Because drones have wing structures, the wings can also generate some lift during cruise to reduce the power consumption of the propellers. Therefore, the forces acting on a drone actually include the propeller force and the wing force, and the resultant external force equation can be expressed in the following form: (Formula 4); in, This represents the net external force acting on the drone; This indicates the wing forces of the drone, including the forces acting on the wings at various points. axis, axis, Force in the axial direction ; This indicates the force exerted by the drone's propellers; Representing the The thrust generated by each propeller varies because each propeller may have a different tilt angle. It can be represented as a vector form in the body coordinate system. Including the Each spiral descending acts on axis, axis, Propeller thrust in the axial direction; The number of propellers contained in the drone, that is, the total number of propellers contained in the drone. An angled propeller Greater than 1; Indicates dynamic pressure; This represents the wing area, specifically the projected area of the wing. , , They represent axis, axis, The thrust coefficient in the axial direction is related to the attitude angle of the UAV. Specifically, it is calculated directly based on the attitude angle of the UAV through a matching mapping table or calculation rules.
[0029] The equation for the net external moment of a UAV can be expressed in the following form: (Formula 5); in, This represents the aerodynamic torque generated on the wing due to the velocity of the incoming airflow; This represents the resultant torque generated by the thrust of each propeller acting on the center of gravity of the aircraft. Indicates the first The lever arm of the propeller force is actually also the first... The position vector of each propeller is an inherent parameter of the propeller. Once the propeller layout is determined, this position vector becomes a constant value. This represents the resultant torque of the anti-torque of each propeller acting on the center of gravity of the aircraft. The representation of the first The torque exerted on the center of gravity of the aircraft by the anti-torque of the propeller itself; These represent the wingspan, mean aerodynamic chord, reference length (e.g., wingspan or fuselage length), roll moment coefficient, pitch moment coefficient, and yaw moment coefficient, respectively.
[0030] The resultant external force of the propeller in Formulas 4 and 5 and the resultant external torque of the propeller The relationship between the power distribution and the rotational speed of each propeller can be expressed by the following power distribution equation: (Formula 6); in, This is a power distribution coefficient matrix, containing the thrust coefficients of each propeller. and torque coefficient and the position vectors of each propeller The tensile force coefficient and torque coefficient can be calibrated through ground tests; This represents the rotational speed of the nth propeller, where n is the number of angled propellers.
[0031] The equation of motion for the center of mass of a UAV can be expressed in the following form: (Formula 7); in, It is a velocity vector containing velocity components along three axes. , This is the transformation matrix from the body coordinate system to the inertial coordinate system. It is the gravitational acceleration vector. This refers to the total mass of the drone; Represents the velocity vector of motion Perform differentiation.
[0032] Substituting Formulas 3, 4, and 5 into Formulas 6 and 7, and combining and rearranging the results, we can express the standard state-space equation form as follows: (Formula 8); in, ; This is the attitude angle vector, including the roll angle, pitch angle, and yaw angle, which can be derived from the roll rate at the previous moment. Pitch angular velocity and yaw rate It can be obtained by performing integration, or it can be obtained directly through sensor detection. That is, for the state-space equation at the current moment, The value is known. The transfer matrix includes the inertia parameters and aerodynamic parameters that need to be identified. It can be pre-configured based on experience or calculated using the transfer matrix identification equation in Embodiment 3 of this invention. This is the propeller characteristic parameter matrix, which also contains known values; The propeller rotational speed vector can be represented by the following form: (Formula Nine); Therefore, the dynamic model of a vertical takeoff and landing fixed-wing UAV with multiple tilted propellers has been completed by Equation 8. It includes the various lift and aerodynamic torques generated by the wing and fuselage assembly and the propellers, as well as the additional effects of the tilted propellers. It fully describes the flight attitude characteristics of a vertical takeoff and landing fixed-wing UAV equipped with fixed tilted propellers. The state space equation reflects the relationship between the velocity components of the three axes of the UAV, as well as the roll rate, pitch rate, and yaw rate, and the rotational speed of each tilted propeller.
[0033] S103. Obtain the actual flight attitude of the UAV based on the state-space equation of the UAV and the real-time rotation speed of each of the inclined propellers, or obtain the adjustment speed of each of the inclined propellers based on the state-space equation of the UAV and the desired flight attitude of the UAV.
[0034] For the state-space equation described in Formula 8 above, the left side includes six unknowns, namely the velocity components of the UAV in three axes. and the roll rate of the drone Pitch angular velocity and yaw rate The unknown on the right side of the equation is the propeller rotation speed vector. That is, the rotational speed of each propeller.
[0035] Therefore, by constructing the state-space equations for the UAV, when it is necessary to control the UAV to fly in a specified attitude, the desired flight attitude (including velocity and angular velocity) can be substituted into the state-space equations to solve for the adjustment speed of each skewed propeller, thereby adjusting and controlling the speed of the skewed propellers to enable the UAV to achieve the desired flight attitude. When it is necessary to obtain the actual flight attitude of the UAV, the speed of each propeller can be read through sensors, and then the real-time speed of each skewed propeller can be substituted into the state-space equations to solve for the actual flight attitude of the UAV.
[0036] The technical solution of this invention obtains the attitude control equations of the UAV based on its attitude angular velocity, moment of inertia, net external torque, and angular velocity tensor; it obtains the state-space equations of the UAV based on the net external force equations, net external torque equations, power distribution equations, center of mass motion equations, and attitude control equations; and it obtains the actual flight attitude of the UAV based on the state-space equations and the real-time rotational speeds of each slanted propeller. Thus, by constructing the state-space equations of the UAV, the actual flight attitude of the UAV can be obtained based on the real-time rotational speeds of each slanted propeller, thereby achieving the detection and acquisition of the UAV's flight attitude. Simultaneously, based on the state-space equations of the UAV and the desired flight attitude of the UAV, the adjustment speeds of each slanted propeller are obtained, thereby achieving accurate control of the UAV's flight attitude.
[0037] Example 2 Figure 2 This is a flowchart of an attitude control method for a drone according to Embodiment 2 of the present invention. The relationship between this embodiment and the above embodiments is that, during the takeoff phase of the drone, in order to avoid interference from wing lift, the horizontal speed of the drone is controlled to 0, so that the drone can maintain a smooth takeoff. Figure 2 As shown, the method specifically includes: S201. Based on the resultant external force of the UAV's propeller, the resultant external torque of the propeller, and the force helix vector, obtain the vertical takeoff equation of the UAV.
[0038] During the takeoff phase of a drone, to maintain a stable takeoff, the drone's horizontal speed is controlled to 0, meaning it generates no force through its wings. At this point, the net external force on the drone is equal to the net external force from the propeller, and the net external torque on the drone is equal to the net external torque from the propeller. The vertical takeoff equation at this time can be expressed in the following form: (Formula 10); in, Represents the force helical vector, including that of drones. axis, axis, The resultant external force in the axial direction, and the UAV's orbital force. axis, axis, The net external torque in the axial direction; the vertical takeoff equation means that, under the premise that the wing does not generate any force, the net external force and net external torque of the UAV's propeller are obtained by transforming the UAV's net external force and net external torque through the transformation matrix from the body coordinate system to the inertial coordinate system.
[0039] S202. Based on the vertical takeoff equation of the UAV and the desired force helical vector of the UAV, obtain the vertical takeoff speed of each of the inclined propellers.
[0040] To ensure a smooth takeoff for the drone, it is necessary to make it... shaft and The net external force in the axial direction is 0, and makes The net external force along the axis is equal to the weight of the drone, and at the same time, it causes it to... axis, axis, The net external torque in the axial direction is 0, which means... As the desired force helical vector, Formula 10 is solved accordingly to obtain the rotational speed of each propeller, that is, the vertical takeoff speed, which reflects the rotational speed value that each propeller should be set to when the UAV takes off vertically and stably during the takeoff phase.
[0041] Optionally, in this embodiment of the invention, obtaining the vertical takeoff speed of each of the inclined propellers based on the vertical takeoff equation of the UAV and the desired force helical vector of the UAV includes: if it is determined that the number of propellers of the UAV is greater than six, obtaining the target functional of the UAV based on the vertical takeoff equation, the power distribution equation and the total energy consumption of the motors of each of the inclined propellers; and obtaining the vertical takeoff speed of each of the inclined propellers based on the target functional.
[0042] Specifically, for Equation 10 above, if the number of propellers of the UAV is greater than 6, the solution for the vertical takeoff speed of Equation 10 is not unique. In this case, while ensuring the stability of the UAV's attitude, the objective functional is to minimize the total power consumption of each propeller motor. as follows: (Formula Eleven); In Formula 11, the first term on the right side represents the total energy consumption of all motors. This is the torque coefficient matrix of the motors for each propeller. The second term on the right is a Lagrange multiplier term, used to ensure that the constraint conditions in Formula 11 are met.
[0043] The objective functional is a mapping that takes a function as input and a scalar as output. In this embodiment of the invention, the objective functional is constructed with the goal of minimizing the total energy consumption of each propeller motor. The final power distribution result for vertical takeoff should satisfy the following form: (Formula 12); Among them, the functional extremum problem in Formula Twelve can be solved by using the Generalized-alpha implicit iterative method to obtain the propeller speed vector with the minimum total power consumption of the motor, and the speed of each propeller can be calculated accordingly. In particular, in order to ensure the attitude stability of the UAV, an identification layer can be added to the outer loop of the power distribution output to iteratively identify the propeller thrust and torque coefficient in the matrix and reduce the distribution error.
[0044] The technical solution of this invention obtains the vertical takeoff equation of the UAV based on the resultant external force, resultant external torque, and force helical vector of the UAV's propellers; and obtains the vertical takeoff speed of each inclined propeller based on the UAV's vertical takeoff equation and the UAV's desired force helical vector. Therefore, by controlling the speed of each propeller during the UAV's takeoff phase, a stable takeoff state is ensured, greatly improving the flight stability of the UAV.
[0045] Example 3 Figure 3 This is a flowchart of an attitude control method for a UAV provided in Embodiment 3 of the present invention. The relationship between this embodiment and the above embodiments is that, in the UAV's level flight state (e.g., uniform level flight state), an attitude observer is constructed to obtain the level flight rotation speed of each propeller of the UAV, such as... Figure 3 As shown, the method specifically includes: S301. Obtain the attitude observer of the UAV.
[0046] When the UAV is in level flight, the wings and fuselage generate some lift, and the remaining lift needs to be compensated by the propeller array. At this time, it is necessary to redistribute the thrust distribution of each propeller according to the flight speed and flight attitude. To this end, the attitude observer of the UAV is first constructed: (Formula Thirteen); in, For observable measurements of the drone's attitude, including pitch, roll, and yaw angles, which can be read by the onboard gyroscope, This is the observation coefficient matrix; due to the influence of external environmental noise and aircraft vibration during UAV flight, the observation values are subject to certain disturbances. .
[0047] S302. Based on the attitude observer and the state space equation of the UAV, obtain the transfer matrix identification equation of the UAV.
[0048] The attitude observer constructed based on Formula 13, combined with the state-space equation of Formula 9, can be based on the propeller rotation speed vector. and observations The parameters in the transfer matrix are identified, and the specific identification equation can be expressed in the following form: (Formula Fourteen); in, This is a forgetting factor to avoid fitting oscillations during the control recursive identification process. Input a differential sequence for the propeller rotation speed. This is a sequence of differencing UAV attitude vectors; Represents the transfer matrix; The identity matrix is used; based on this, the least-squares unbiased estimate of the transformation matrix can be calculated using the propeller input (i.e., the rotational speed of each propeller) and the observed values of the attitude vector at different times. The essence of the transfer matrix identification equation is to estimate the error dynamics through the attitude observer and derive the constraints of the state-space equation in reverse.
[0049] S303. Obtain the transfer matrix according to the transfer matrix identification equation, and obtain the level flight speed of each of the inclined propellers according to the transfer matrix.
[0050] After identifying the parameters in the transfer matrix, the iterative relationship of the propeller speed vector under the stable attitude control state of the UAV can be constructed as follows: (Formula 15); in, This is the iteration step size control factor, which is between 0 and 1 and can be pre-configured as needed. and This is the weighting coefficient matrix, which can also be pre-configured as needed. For example, it can be configured as a unit diagonal matrix. Based on this, using Formula 15, the level flight speed of each inclined propeller at the current moment can be obtained according to the level flight speed of each propeller at the previous moment.
[0051] The technical solution of this invention, after acquiring the attitude observer of the UAV, obtains the transfer matrix identification equation of the UAV based on the attitude observer and the state space equation, obtains the transfer matrix based on the transfer matrix identification equation, and obtains the level flight speed of each skewed propeller based on the transfer matrix. Thus, by iteratively obtaining the level flight speed of each skewed propeller, attitude stability during UAV level flight is ensured through propeller speed compensation.
[0052] Example 4 Figure 4 This is a flowchart of an attitude control method for a UAV provided in Embodiment 4 of the present invention. The relationship between this embodiment and the above embodiments is that, during the level flight acceleration phase, based on a feedforward control strategy, the influence of the additional pitching moment generated by the propeller is eliminated, such as... Figure 4 As shown, the method specifically includes: S401. Obtain the maximum control torque of the canard control surfaces of the UAV, and compare the maximum control torque with the thrust pitch torque of each of the inclined propellers.
[0053] The canard, also known as the forewing, is a component used to control the pitch attitude of an unmanned aerial vehicle (UAV). Control surfaces refer to the control surfaces that can be manipulated on the canard. By deflecting the control surfaces of the canard, the force of airflow on the canard can be changed, thereby generating a control torque, which is the torque around the center of gravity of the UAV. This torque is related to the area and airfoil of the canard. The maximum control torque of the canard refers to the maximum torque value that the canard can generate within the allowable deflection range, and it is also the upper limit of the canard's control capability. The maximum control torque of the canard can be determined based on the area and airfoil of the canard.
[0054] Since thrust and pull are reaction forces, the magnitude of the thrust pitching moment is actually equal to the resultant moment generated by the thrust of each propeller acting on the aircraft's center of gravity, as shown in Formula 5 above. Therefore, by vectorizing the propeller rotation speed at the previous moment... Substitute the values into Formula 6 to calculate the resultant external force of the propeller. Then, based on the resultant external force of the propeller and the position vectors of each propeller, the thrust pitching moment at the previous moment can be calculated, which is to say, the thrust pitching moment can be calculated. The maximum control moment is then compared with the thrust pitching moment.
[0055] S402. If it is determined that the maximum control torque is greater than or equal to the thrust pitching torque, obtain the feedforward compensation equation based on the deflection angle of the canard control surface and the rotational speed of each of the inclined propellers.
[0056] When the maximum control torque of the canard control surface is greater than or equal to the additional torque generated by the thrust of the skewed propeller, it indicates that the control capability of the canard can offset the attitude disturbance caused by the propeller thrust, ensuring that the UAV can stably control its pitch attitude. In this case, the canard control surface feedforward control method is adopted, and the polynomial function (i.e., the feedforward compensation equation) between the deflection angle of the canard control surface and the rotational speed of each skewed propeller is constructed as follows: (Formula Sixteen); in, This refers to the deflection angle of the canard control surface, which is also the feedforward compensation angle of the canard control surface. The coefficient matrix can be pre-calculated based on the aerodynamic geometry of the UAV and the propeller dynamic parameters.
[0057] S403. Based on the feedforward compensation equation and the real-time rotational speed of each of the inclined propellers, obtain the feedforward compensation angle of the canard control surface.
[0058] By substituting the real-time rotational speed of each skewed propeller into Formula 16 above, the feedforward compensation angle of the canard control surface can be calculated. Then, by compensating for this angle, the additional pitching moment generated when the skewed propeller increases thrust can be offset, thus preventing the UAV from becoming unstable and improving the attitude stability of the UAV.
[0059] S404. If it is determined that the maximum control torque is less than the thrust pitch torque, the feedforward compensation angle of the canard control surface is obtained according to the feedforward compensation equation, the real-time rotational speed of each of the skewed propellers and the relaxation factor, and the feedforward compensation rotational speed of each of the skewed propellers is obtained according to the rotational speed of each of the skewed propellers and the relaxation factor.
[0060] When the maximum control torque of the canard control surface deflection is less than the thrust additional torque, a combined canard control surface and skewed propeller feedforward method is adopted. First, the original feedforward compensation angle is obtained through the above feedforward compensation equation and the real-time rotational speed of each skewed propeller. Then, the original feedforward compensation angle and relaxation factor are used to obtain the feedforward compensation angle. The actual feedforward compensation angle is calculated and obtained, thereby offsetting part of the pitching moment through the canard control surface deflection angle feedforward; where the relaxation factor is... Greater than 0 and less than 1; the feedforward compensation angle of the canard control surface can be expressed in the following form: ; in, Indicates the original feedforward compensation angle. This indicates the actual feedforward compensation angle.
[0061] Then, based on the rotational speed and relaxation factor of each skewed propeller, the feedforward compensation speed of each skewed propeller is obtained. By adjusting the propeller speed, the skewed propellers located at the front of the UAV generate part of the pitching torque, which is used to offset part of the pitching torque, thereby achieving the balance of the overall pitching torque of the UAV. The feedforward compensation speed of each skewed propeller can be expressed in the following form: ; in, The feedforward compensation speed for each skewed propeller.
[0062] The technical solution of this invention compares the maximum control torque of the canard control surface with the thrust pitch torque of each slanted propeller to obtain the feedforward compensation angle of the canard control surface, or obtain the feedforward compensation angle of the canard control surface and the feedforward compensation speed of each slanted propeller. This eliminates the additional pitch torque generated by the propeller thrust through the feedforward compensation mechanism, avoids instability of the UAV, and improves the attitude stability of the UAV.
[0063] Example 5 Figure 5 This is a structural block diagram of an attitude control device for a drone provided in Embodiment 5 of the present invention. The device specifically includes: The attitude equation acquisition module 501 is used to acquire the attitude control equation of the UAV based on the UAV's attitude angular velocity, moment of inertia, net external torque and rotational angular velocity tensor; wherein the UAV is equipped with multiple oblique propellers. The state equation acquisition module 502 is used to acquire the state space equation of the UAV based on the resultant external force equation, resultant external torque equation, power distribution equation, center of mass motion equation and attitude control equation of the UAV; wherein, the power distribution equation represents the relationship between the resultant external force and resultant external torque of the UAV propeller and the rotational speed of each of the inclined propellers. The flight attitude acquisition module 503 is used to acquire the actual flight attitude of the UAV based on the UAV's state space equation and the real-time rotation speed of each of the inclined propellers, or to acquire the adjustment speed of each of the inclined propellers based on the UAV's state space equation and the UAV's desired flight attitude.
[0064] The technical solution of this invention obtains the attitude control equations of the UAV based on its attitude angular velocity, moment of inertia, net external torque, and angular velocity tensor; it obtains the state-space equations of the UAV based on the net external force equations, net external torque equations, power distribution equations, center of mass motion equations, and attitude control equations; and it obtains the actual flight attitude of the UAV based on the state-space equations and the real-time rotational speeds of each slanted propeller. Thus, by constructing the state-space equations of the UAV, the actual flight attitude of the UAV can be obtained based on the real-time rotational speeds of each slanted propeller, thereby achieving the detection and acquisition of the UAV's flight attitude. Simultaneously, based on the state-space equations of the UAV and the desired flight attitude of the UAV, the adjustment speeds of each slanted propeller are obtained, thereby achieving accurate control of the UAV's flight attitude.
[0065] Optionally, the attitude control device of the UAV is further configured to obtain the vertical takeoff equation of the UAV based on the resultant external force of the UAV's propeller, the resultant external torque of the propeller, and the force helix vector; and to obtain the vertical takeoff speed of each of the inclined propellers based on the vertical takeoff equation of the UAV and the desired force helix vector of the UAV.
[0066] Optionally, the attitude control device of the UAV is further configured to, if it is determined that the number of propellers of the UAV is greater than six, obtain the target functional of the UAV based on the vertical takeoff equation, the power distribution equation and the total energy consumption of the motors of each of the inclined propellers; and obtain the vertical takeoff speed of each of the inclined propellers based on the target functional.
[0067] Optionally, the attitude control device of the UAV is further configured to acquire the attitude observer of the UAV; acquire the transfer matrix identification equation of the UAV based on the attitude observer of the UAV and the state space equation; acquire the transfer matrix based on the transfer matrix identification equation; and acquire the level flight speed of each of the inclined propellers based on the transfer matrix.
[0068] Optionally, the attitude control device of the UAV is further configured to obtain the maximum control torque of the canard control surface of the UAV and compare the maximum control torque with the thrust pitch torque of each of the slanted propellers; if it is determined that the maximum control torque is greater than or equal to the thrust pitch torque, a feedforward compensation equation is obtained based on the deflection angle of the canard control surface and the rotational speed of each of the slanted propellers; and the feedforward compensation angle of the canard control surface is obtained based on the feedforward compensation equation and the real-time rotational speed of each of the slanted propellers.
[0069] Optionally, the attitude control device of the UAV is further configured to, if it is determined that the maximum control torque is less than the thrust pitch torque, obtain the feedforward compensation angle of the canard control surface according to the feedforward compensation equation, the real-time rotational speed of each of the skewed propellers and the relaxation factor, and obtain the feedforward compensation rotational speed of each of the skewed propellers according to the rotational speed of each of the skewed propellers and the relaxation factor.
[0070] The above-described device can execute the attitude control method for a UAV provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects for executing the method. Technical details not described in detail in this embodiment can be found in the attitude control method for a UAV provided in any embodiment of the present invention.
[0071] Example 6 Figure 6 A schematic diagram of an electronic device 10, which can be used to implement embodiments of the present invention, is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, electronic devices, blade electronic devices, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices (such as helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.
[0072] like Figure 6 As shown, the electronic device 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12 or a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer program stored in the ROM 12 or loaded from storage unit 18 into the RAM 13. The RAM 13 can also store various programs and data required for the operation of the electronic device 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.
[0073] Multiple components in electronic device 10 are connected to I / O interface 15, including: input unit 16, such as keyboard, mouse, etc.; output unit 17, such as various types of displays, speakers, etc.; storage unit 18, such as disk, optical disk, etc.; and communication unit 19, such as network card, modem, wireless transceiver, etc. Communication unit 19 allows electronic device 10 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.
[0074] Processor 11 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Processor 11 performs the various methods and processes described above, such as attitude control methods for unmanned aerial vehicles.
[0075] In some embodiments, the attitude control method for a UAV can be implemented as a computer program tangibly contained in a computer-readable storage medium, such as a storage unit. In some embodiments, part or all of the computer program can be loaded and / or installed on a heterogeneous hardware accelerator via ROM and / or a communication unit. When the computer program is loaded into RAM and executed by a processor, one or more steps of the attitude control method for a UAV described above can be performed. Alternatively, in other embodiments, the processor can be configured to perform the attitude control method for a UAV by any other suitable means (e.g., by means of firmware).
[0076] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.
[0077] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.
[0078] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.
[0079] To provide user interaction, the systems and techniques described herein can be implemented on a heterogeneous hardware accelerator, which includes: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the heterogeneous hardware accelerator. Other types of devices can also be used to provide user interaction; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or haptic feedback); and input from the user can be received in any form (including sound input, voice input, or haptic input).
[0080] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or middleware components (e.g., application servers), or frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.
[0081] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.
[0082] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.
[0083] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.
Claims
1. An attitude control method for an unmanned aerial vehicle (UAV), characterized in that, include: The attitude control equations of the UAV are obtained based on its attitude angular velocity, moment of inertia, net external torque, and rotational angular velocity tensor; wherein the UAV is equipped with multiple obliquely mounted propellers. Based on the resultant external force equation, resultant external torque equation, power distribution equation, center of mass motion equation, and attitude control equation of the UAV, the state space equation of the UAV is obtained; wherein, the power distribution equation represents the relationship between the resultant external force and resultant external torque of the UAV propeller and the rotational speed of each of the inclined propellers. The actual flight attitude of the UAV is obtained based on the state-space equation of the UAV and the real-time rotation speed of each of the inclined propellers, or the adjustment speed of each of the inclined propellers is obtained based on the state-space equation of the UAV and the desired flight attitude of the UAV.
2. The attitude control method for a UAV according to claim 1, characterized in that, The attitude control method for the UAV also includes: The vertical takeoff equation of the UAV is obtained based on the resultant external force of the UAV's propeller, the resultant external torque of the propeller, and the force helix vector. Based on the vertical takeoff equation of the UAV and the desired force helical vector of the UAV, the vertical takeoff speed of each of the inclined propellers is obtained.
3. The attitude control method for a UAV according to claim 2, characterized in that, The step of obtaining the vertical takeoff speed of each of the inclined propellers based on the vertical takeoff equation of the UAV and the desired force helical vector of the UAV includes: If it is determined that the number of propellers of the UAV is greater than six, the target functional of the UAV is obtained according to the vertical take-off equation, the power distribution equation and the total energy consumption of the motors of each of the inclined propellers; Based on the target functional, the vertical takeoff speed of each of the inclined propellers is obtained.
4. The attitude control method for a UAV according to claim 1, characterized in that, After obtaining the state-space equations of the UAV based on the resultant external force equations, resultant external moment equations, dynamic distribution equations, center of mass motion equations, and attitude control equations, the process further includes: Obtain the attitude observer of the UAV; Based on the attitude observer and state space equation of the UAV, the transfer matrix identification equation of the UAV is obtained; The transfer matrix is obtained according to the transfer matrix identification equation, and the level flight speed of each of the inclined propellers is obtained according to the transfer matrix.
5. The attitude control method for a UAV according to claim 1, characterized in that, The attitude control method for the UAV also includes: The maximum control torque of the canard control surfaces of the UAV is obtained, and the maximum control torque is compared with the thrust pitch torque of each of the inclined propellers. If it is determined that the maximum control torque is greater than or equal to the thrust pitching torque, the feedforward compensation equation is obtained based on the deflection angle of the canard control surface and the rotational speed of each of the inclined propellers. The feedforward compensation angle of the canard control surface is obtained based on the feedforward compensation equation and the real-time rotational speed of each of the inclined propellers.
6. The attitude control method for a UAV according to claim 5, characterized in that, After comparing the maximum control torque with the thrust pitching torque of each of the skewed propellers, the method further includes: If the maximum control torque is determined to be less than the thrust pitch torque, the feedforward compensation angle of the canard control surface is obtained according to the feedforward compensation equation, the real-time rotational speed of each of the skewed propellers and the relaxation factor, and the feedforward compensation rotational speed of each of the skewed propellers is obtained according to the rotational speed of each of the skewed propellers and the relaxation factor.
7. An attitude control device for an unmanned aerial vehicle (UAV), characterized in that, include: The attitude equation acquisition module is used to acquire the attitude control equation of the UAV based on the UAV's attitude angular velocity, moment of inertia, net external torque, and rotational angular velocity tensor; wherein the UAV is equipped with multiple obliquely mounted propellers; The state equation acquisition module is used to acquire the state space equation of the UAV based on the resultant external force equation, resultant external torque equation, power distribution equation, center of mass motion equation and attitude control equation of the UAV; wherein, the power distribution equation represents the relationship between the resultant external force and resultant external torque of the UAV propeller and the rotational speed of each of the inclined propellers. The flight attitude acquisition module is used to acquire the actual flight attitude of the UAV based on the UAV's state space equation and the real-time rotation speed of each of the inclined propellers, or to acquire the adjustment speed of each of the inclined propellers based on the UAV's state space equation and the UAV's desired flight attitude.
8. An electronic device, characterized in that, The electronic device includes: At least one processor; and A memory communicatively connected to the at least one processor; wherein, The memory stores a computer program that can be executed by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the attitude control method of the UAV according to any one of claims 1-6.
9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that, when executed by a processor, implement the attitude control method of the UAV according to any one of claims 1-6.
10. A computer program product comprising a computer program that, when executed by a processor, implements the attitude control method of the UAV according to any one of claims 1-6.