Stable flight control method for multi-rotor unmanned aerial vehicle based on finite-time neurodynamics
11378983 · 2022-07-05
Assignee
Inventors
Cpc classification
B64U2201/00
PERFORMING OPERATIONS; TRANSPORTING
B64U2201/10
PERFORMING OPERATIONS; TRANSPORTING
B64C39/024
PERFORMING OPERATIONS; TRANSPORTING
B64U10/16
PERFORMING OPERATIONS; TRANSPORTING
International classification
G05D1/10
PHYSICS
Abstract
Provided is a stable flight control method for a multi-rotor unmanned aerial vehicle based on finite-time neurodynamics, comprising the following implementation process: 1) acquiring real-time flight orientation and attitude data through airborne sensors, and analyzing and processing kinematic problems of the aerial vehicle through an airborne processor to establish a dynamics model of the aerial vehicle; 2) designing a finite-time varying-parameter convergence differential neural network solver according to a finite-time varying-parameter convergence differential neurodynamics design method; 3) solving output control parameters of motors of the aerial vehicle through the finite-time varying-parameter convergence differential neural network solver using the acquired real-time orientation and attitude data; and 4) transmitting results to speed regulators of the motors of the aerial vehicle to control the motion of the unmanned aerial vehicle. Based on the finite-time varying-parameter convergence differential neurodynamics method, the invention can approximate the correct solution of the problem in a quick, accurate and real-time way, and can well solve a variety of time-varying problems such as matrix, vector, algebra and optimization.
Claims
1. A stable flight control method for a multi-rotor unmanned aerial vehicle based on finite-time neurodynamics, the control method comprising the steps of: S1, acquiring real-time flight orientation and attitude data of the multi-rotor unmanned aerial vehicle through sensors thereof, and analyzing and processing kinematic problems of the aerial vehicle correspondingly through an airborne processor to establish a dynamics model of the aerial vehicle; S2, designing a finite-time varying-parameter convergence differential neural network solver for the dynamics model of the multi-rotor aerial vehicle according to a finite-time varying-parameter convergence differential neurodynamics design method; S3, solving output control parameters of motors of the aerial vehicle through the finite-time varying-parameter convergence differential neural network solver using the acquired real-time orientation and attitude data of the aerial vehicle; and S4, transmitting the solved output control parameters to speed regulators of the motors of the aerial vehicle to control the motion of the unmanned aerial vehicle; wherein the analyzing and processing kinematic problems of the aerial vehicle correspondingly through an airborne processor to establish a dynamics model of the aerial vehicle of step S1 specifically comprises: ignoring the effect of air resistance on the aerial vehicle, such that a physical model can be established for the aerial vehicle system:
2. The stable flight control method for a multi-rotor A unmanned aerial vehicle based on finite-time neurodynamics of claim 1, wherein the step of by means of the finite-time varying-parameter convergence differential neurodynamics design method, designing a system parameter deviation function of the finite-time varying-parameter convergence differential neural network about the output control parameters u.sub.1˜u.sub.4 in respect to the z-axis height z(t), the roll angle ϕ(t), the pitch angle θ(t) and the yaw angle ψ(t), respectively, specifically comprises: S201, for the z-axis height z(t), according to a set target height value and an actual height value z.sub.T(t) in the z-axis direction, defining a deviation function e.sub.z1 about the actual height value z(t) on a position layer as follows: e.sub.z1(t)=z(t)−z.sub.T(t), in order to enable the actual value z(t) to converge to the time-varying target value z.sub.T(t), designing a neurodynamics equation ė.sub.z1(t)=−γ(t)Φ(e.sub.z1(t),t) based on a deviation function according to the finite-time varying-parameter convergence differential neurodynamics design method, wherein γ(t)=p+t.sup.p is a time-varying parameter representing a regulatory factor for the rate of convergence;
ż(t)−ż.sub.T(t)+(t.sup.p+p)Φ(e.sub.z1(t),t)=0; (3) the position layer z(t) can converge to the time-varying target value z.sub.T(t) in a super-exponential manner within a finite time, however, since equation (3) does not contain relevant information about the control parameters u.sub.1˜u.sub.4, the solution of the control parameters cannot be realized, therefore, it is necessary to further design the deviation function including a velocity layer ż(t) and an acceleration layer {umlaut over (z)}(t), thus defining e.sub.z2(t)=ż(t)−ż.sub.T(t)+(t.sup.p+p)Φ(e.sub.z1(t),t); according to the finite-time varying-parameter convergence differential neural network design method, the dynamics equation ė.sub.z2(t)=−γ(t)Φ(e.sub.z2(t),t) based on the deviation function can be designed,
{umlaut over (z)}(t)−{umlaut over (Z)}.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.z1(t),t)+Φ(e.sub.z2(t),t)+pt.sup.p-1Φ(e.sub.z1(t),t)=0 (4) when equation (4) is established, the velocity layer ż(t) will converge to
E.sub.z(t)={umlaut over (z)}(t)−{umlaut over (z)}.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.z1(t),t)+Φ(e.sub.z2(t),t)+pt.sup.p-1Φ(e.sub.z1(t),t) (5) in order to obtain an actual model of the neural network, in combination with kinetic equation (2), equation (5) can be rewritten into
E.sub.z(t)=a.sub.z(t)u.sub.1(t)+b.sub.z(t), (6)
{dot over (ϕ)}(t)−{dot over (ϕ)}.sub.T(t)+(t.sup.p+p)Φ(e.sub.ϕ1(t),t)=0, (7) ϕ(t) will converge to the target angle ϕ.sub.T(t) in a super-exponential manner within finite time; since {umlaut over (ϕ)}(t) is known, it is necessary to solve the equation involving {umlaut over (ϕ)}(t); in order to obtain the equation involving {umlaut over (ϕ)}(t), the error function e.sub.ϕ2={dot over (ϕ)}(t)−{dot over (ϕ)}.sub.T(t)+(t.sup.p+p)Φ(e.sub.ϕ1(t),t) is set by the same method and ė.sub.ϕ2(t)={umlaut over (ϕ)}(t)−{umlaut over (ϕ)}.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.ϕ1(t),t)+pt.sup.p-1Φ(e.sub.ϕ1(t),t),
{umlaut over (ϕ)}(t)−{umlaut over (ϕ)}.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.ϕ1(t),t)+Φ(e.sub.ϕ2(t),t)+pt.sup.p-1Φ(e.sub.ϕ1(t),t)=0 (8) when equation (8) is established, the velocity layer {dot over (ϕ)}(t) will converge to {dot over (ϕ)}.sub.T(t) within finite time in a super-exponential manner, according to which the deviation function can be considered
E.sub.ϕ={umlaut over (ϕ)}(t)−{umlaut over (ϕ)}.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.ϕ1(t),t)+Φ(e.sub.ϕ2(t),t)+pt.sup.p-1Φ(e.sub.ϕ1(t),t) (9) when the aerial vehicle reaches a target state, according to the dynamics model equation, the deviation function can be converted into
{dot over (θ)}(t)−{dot over (θ)}.sub.T(t)+(t.sup.p+p)Φ(e.sub.θ1(t),t)=0, (11) θ(t) will converge to the target angle θ.sub.T(t) in a super-exponential manner within finite time; since {umlaut over (θ)}(t) is known, it is necessary to solve the equation involving {umlaut over (θ)}(t); in order to obtain the equation involving {umlaut over (θ)}(t), the error function e.sub.θ2={dot over (θ)}(t)−{dot over (θ)}.sub.T(t)+(t.sup.p+p)Φ(e.sub.θ1(t),t) is set by the same method and ė.sub.θ2(t)={umlaut over (θ)}(t)−{umlaut over (θ)}.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.θ1(t),t)+pt.sup.p-1Φ(e.sub.θ1(t),t),
{umlaut over (θ)}(t)−{umlaut over (θ)}.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.θ1(t),t)+Φ(e.sub.θ2(t),t)+pt.sup.p-1Φ(e.sub.θ1(t),t)=0 (12) when equation (12) is established, the velocity layer {dot over (θ)}(t) will converge to {dot over (θ)}.sub.T(t) within finite time in a super-exponential manner, according to which the deviation function can be considered
E.sub.θ(t)={umlaut over (θ)}(t)−{umlaut over (θ)}.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.θ1(t),t)+Φ(e.sub.θ2(t),t)+pt.sup.p-1Φ(e.sub.θ1(t),t) (13) when the aerial vehicle reaches a target state, according to the dynamics model equation, the deviation function can be converted into
{dot over (ψ)}(t)−{dot over (ψ)}.sub.T(t)+(t.sup.p+p)Φ(e.sub.ψ1(t),t)=0 (15) ψ(t) will converge to the target angle ψ.sub.T(t) in a super-exponential manner within finite time; since {umlaut over (ψ)}(t) is known, it is necessary to solve the equation involving {umlaut over (ψ)}(t); in order to obtain the equation involving {umlaut over (ψ)}(t), the error function e.sub.ψ2={dot over (ψ)}(t)−{dot over (ψ)}.sub.T(t)+(t.sup.p+p)Φ(e.sub.ψ1(t),t) is set by the same method and
{umlaut over (ψ)}(t)−{umlaut over (ψ)}.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.ψ1(t),t)+Φ(e.sub.ψ2(t),t)+pt.sup.p-1Φ(e.sub.ψ1(t),t)=0 (16) when equation (16) is established, the velocity layer {dot over (ψ)}(t) will converge to {dot over (ψ)}.sub.T(t) within finite time in a super-exponential manner, according to which the deviation function can be considered
E.sub.ψ(t)={dot over (ψ)}(t)−{dot over (ψ)}.sub.T(t)+(p+t.sup.p)Φ(t),t)+Φ(e.sub.ψ2(t),t)+pt.sup.p-1Φ(e.sub.ψ1(t),t) (17) when the aerial vehicle reaches a target state, according to the dynamics model equation, the deviation function can be converted into
3. The stable flight control method for a multi-rotor unmanned aerial vehicle based on finite-time neurodynamics of claim 2, wherein the step of designing the finite-time varying-parameter convergence differential neural network solver according to the obtained system parameter deviation function of the finite-time varying-parameter convergence differential neural network about the output control parameters u.sub.1˜u.sub.4, respectively, specifically comprises: S211, for the z-axis height z(t), by using the finite-time varying-parameter convergence differential neural network design method, designing Ė.sub.z(t)=−γ(t)Φ(E.sub.z(t),t), and substituting equation (6) and the derivative Ė.sub.z(t)={dot over (a)}.sub.z(t)u.sub.1(t)+a.sub.z(t){dot over (u)}.sub.1(t)+{dot over (b)}.sub.z(t), so that an implicit dynamics equation of the finite-time varying-parameter convergence differential neural network can be obtained:
a.sub.z(t){dot over (u)}.sub.1(t)=−({dot over (a)}.sub.z(t)u.sub.1(t)+{dot over (b)}.sub.z(t)+γ(t)Φ(E.sub.z(t),t)) (19) the position z(t) and velocity ż(t) will converge to a target position z.sub.T(t) and a target velocity ż.sub.T(t), respectively, in a super-exponential manner within finite time; S212, for the roll angle ϕ(t), according to the finite-time varying-parameter convergence differential neurodynamics design method, designing Ė.sub.ϕ(t)=−γ(t)Φ(E.sub.ϕ(t),t), and substituting equation (10) and its derivative
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1)
(2)
(3)
(4)
(5)
DETAILED DESCRIPTION OF EMBODIMENTS
(6) In order to make the objectives, technical solutions and advantages of embodiments of the invention clearer, the technical solutions in embodiments of the invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the invention. Apparently, the described embodiments are a part, but not all of the embodiments of the invention. Based on the embodiments of the invention, all other embodiments obtained by those of ordinary skill in the art without involving any inventive effort fall within the scope of protection of the invention.
Embodiments
(7)
(8) As shown in the figure, a stable flight control method for a multi-rotor unmanned aerial vehicle based on finite-time neurodynamics comprises the steps of:
(9) S1, acquiring real-time flight operation data of a multi-rotor unmanned aerial vehicle through an airborne attitude sensor and corresponding height and position sensors thereof, establishing a dynamics model of the aerial vehicle, and analyzing and processing kinematic problems of the aerial vehicle correspondingly through a processor borne by the multi-rotor unmanned aerial vehicle;
(10) S2, designing a finite-time varying-parameter convergence differential neural network solver for the dynamics model of the multi-rotor aerial vehicle according to a finite-time varying-parameter convergence differential neurodynamics design method;
(11) S3, solving output control parameters of motors of the aerial vehicle, through the finite-time varying-parameter convergence differential neural network solver designed in step S2 and using the real-time operation data and target attitude data of the aerial vehicle acquired in step S1; and
(12) S4, transmitting results of step S3 to speed regulators of the motors of the aerial vehicle to control the motion of the multi-rotor unmanned aerial vehicle.
(13) The mechanism shown in
(14)
(15) (1) six motors of the six-rotor aerial vehicle are defined No. 1 to No. 6 in the clockwise direction;
(16) (2) the x-axis extends in the direction of No. 1 rotor arm and points to the forward direction of the aerial vehicle through the center of gravity of the body;
(17) (3) the y-axis extends in the direction of the axis of symmetry of No. 2 and No. 3 rotor arms and points to the right motion direction of the aerial vehicle through the center of gravity of the body;
(18) (4) the z-axis extends upwardly perpendicular to the plane of the six rotors and points to the climbing direction of the aerial vehicle through the center of gravity of the body;
(19) (5) the pitch angle θ(t) is an included angle between the x-axis of the body and the geodetic horizontal plane, and is set to be positive in the downward direction;
(20) (6) the roll angle ϕ(t) is an included angle between the z-axis of the body and the geodetic vertical plane passing through the x-axis of the body, and is set to be positive when the body is rightward; and
(21) (7) the yaw angle ψ(t) is an included angle between the projection of the x-axis of the body on the geodetic horizontal plane and the x-axis of a geodetic coordinate system, and is set to be positive when the nose of the aerial vehicle is leftward.
(22) According to the relevant steps of the flow chart, detailed algorithm analysis is carried out for the invention. First, with the above definition of the attitude variables of the aerial vehicle, real-time attitude data θ(t) ϕ(t) and ψ(t) of the aerial vehicle may be acquired by sensors such as gyros and accelerometers borne by the multi-rotor aerial vehicle by means of quaternion algebra, Kalman filtering and other algorithms, and position data x(t), y(t) and z(t) of the aerial vehicle in the three-dimensional space is acquired by using altitude sensors and position sensors. The above completes the relevant contents of data acquisition 1 by the sensors in the flow chart.
(23) Based on the previous physical model analysis process, according to different rotor aerial vehicle models, physical model equations and dynamics equations for the aerial vehicle are established, and dynamics analysis may be completed by means of the following aerial vehicle dynamics modeling steps:
(24) ignoring the effect of air resistance on the aerial vehicle, such that a physical model can be established for the aerial vehicle system:
(25)
(26) wherein m is a total mass of the aerial vehicle, I is a 3×3 identity matrix, J is a rotational inertia matrix of the aerial vehicle, v and W are a velocity vector and an angular velocity vector of the aerial vehicle in a ground coordinate system, F and G are an axial component vector of an output resultant force of the motors of the aerial vehicle and an axial component vector of gravity of the aerial vehicle, respectively, and T is a rotational torque vector of the aerial vehicle;
(27) establishing a ground coordinate system X.sub.G and an aerial vehicle body coordinate system X.sub.U, wherein the ground coordinate system and the body coordinate system have the following relationship: X.sub.U=KX.sub.G, in which conversion relationship, K is a rotation conversion matrix between the ground coordinate system and the body coordinate system, which can be expressed as
(28)
(29) wherein, for the convenience of writing, C.sub.θ represents cos θ(t), S.sub.θ represents sin θ(t), θ(t) is the pitch angle, ψ(t) is the yaw angle, and ϕ(t) is the roll angle;
(30) according to the coordinate conversion theory, in a translation direction and a rotation direction of the aerial vehicle, basing on the above physical model, such that the following dynamics equation in the aerial vehicle body coordinate system can be obtained
(31)
(32) wherein x, y, z are position coordinates of the aerial vehicle in the world coordinate system, respectively; J.sub.x, J.sub.y and J.sub.z are rotational inertia of the aerial vehicle in x-axis, y-axis and z-axis directions, respectively; l is an arm length; g is gravitational acceleration; synthesized control parameters u.sub.1˜u.sub.4 consist of output thrust of the motors of the aerial vehicle and a synthesized torque, u.sub.1(t) is a resultant force in a vertical ascending direction of the aerial vehicle, u.sub.2(t) is a resultant force in a roll angle direction, u.sub.3(t) is a resultant force in a pitch angle direction, and u.sub.4(t) is the synthesized torque in a yaw angle direction.
(33) The designing a finite-time varying-parameter convergence differential neural network solver for the dynamics model of the multi-rotor aerial vehicle according to a finite-time varying-parameter convergence differential neurodynamics design method of step S2 specifically comprises:
(34) by means of the finite-time varying-parameter convergence differential neurodynamics design method, designing a system parameter deviation function of the finite-time varying-parameter convergence differential neural network about the output control parameters u.sub.1˜u.sub.4 in respect to the z-axis height z(t), the roll angle ϕ(t), the pitch angle θ(t) and the yaw angle ψ(t), respectively; and
(35) designing the finite-time varying-parameter convergence differential neural network solver according to the obtained system parameter deviation function of the finite-time varying-parameter convergence differential neural network about the output control parameters u.sub.1˜u.sub.4, respectively.
(36) In step S3, the step of by means of the finite-time varying-parameter convergence differential neurodynamics design method, designing a system parameter deviation function of the finite-time varying-parameter convergence differential neural network about the output control parameters u.sub.1˜u.sub.4 in respect to the z-axis height z(t), the roll angle ϕ(t) the pitch angle θ(t) and the yaw angle ψ(t), respectively, specifically comprises:
(37) for the z-axis height z(t), according to a set target height value and an actual height value z.sub.T(t) in the z-axis direction, defining a deviation function e.sub.z1 about the actual height value z(t) on a position layer as follows: e.sub.z1(t)=z(t)−z.sub.T(t), in order to enable the actual value z(t) to converge to the time-varying target value z.sub.T(t), designing a neurodynamics equation ė.sub.z1(t)=−γ(t)Φ(e.sub.z1(t),t) based on a deviation function according to the finite-time varying-parameter convergence differential neurodynamics design method, wherein γ(t)=p+t.sup.p is a time-varying parameter representing a regulatory factor for the rate of convergence;
(38)
(39) according to the deviation function e.sub.z1(t)=z(t)−z.sub.T(t), ė.sub.z1=ż(t)−ż.sub.T(t) can be obtained; by substituting e.sub.z1(t)=z(t)−z.sub.T(t) and ė.sub.z1=ż(t)−ż.sub.T(t) into ė.sub.z1(t)=−γ(t)Φ(e.sub.z1(t),t), we can obtain ż(t)−ż.sub.T(t)=−(t.sup.p+p)Φ(e.sub.z1(t),t), that is
ż(t)−ż.sub.T(t)+(t.sup.p+p)Φ(e.sub.z1(t),t)=0; (3)
(40) the position layer z(t) can converge to the time-varying target value z.sub.T(t) in a super-exponential manner within a finite time, however, since equation (3) does not contain relevant information about the control parameters u.sub.1˜u.sub.4, the solution of the control parameters cannot be realized, therefore, it is necessary to further design the deviation function including a velocity layer ż(t) and an acceleration layer {umlaut over (z)}(t), thus defining e.sub.z2(t)=ż(t)−ż.sub.T(t)+(t.sup.p+p)Φ(e.sub.z1(t),t); according to the finite-time varying-parameter convergence differential neural network design method, the dynamics equation ė.sub.z2(t)=−γ(t)Φ(e.sub.z2(t),t) based on the deviation function can be designed,
(41)
(42) according to e.sub.z2(t)=ż(t)−ż.sub.T(t)+(t.sup.p+p)Φ(e.sub.z1(t),t) the derivative ė.sub.z2(t) of the deviation function e.sub.z2(t) is known as: ė.sub.z2(t)={umlaut over (z)}(t)−ż.sub.T(t)+(p+t.sup.p)Φ(e.sub.z1(t),t)+pt.sup.p-1Φ(e.sub.z1(t),t), by substituting the above equations about e.sub.z2(t) and ė.sub.z2(t) into the equation ė.sub.φ2(t)=−γ(t)Φ(e.sub.ϕ2(t)t), the following function can be obtained:
{umlaut over (z)}(t)−{umlaut over (z)}(t)+(p+t.sup.p){dot over (Φ)}(e.sub.z1(t),t)+Φ(e.sub.z2(t),t)+pt.sup.p-1Φ(e.sub.z1(t),t)=0 (4)
(43) when equation (4) is established, the velocity layer ż(t) will converge to ż.sub.T(t) within finite time in a super-exponential manner, according to which the deviation function can be considered
E.sub.z(t)={umlaut over (z)}(t)−Ż.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.z1(t),t)+Φ(e.sub.z2(t),t)+pt.sup.p-1Φ(e.sub.z1(t),t) (5)
in order to obtain an actual model of the neural network, in combination with kinetic equation (2), equation (5) can be rewritten into
E.sub.z(t)=a.sub.z(t)u.sub.1(t)+b.sub.z(t), (6)
wherein
(44)
(45) b.sub.z(t)=−g−{umlaut over (z)}.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.z1(t),t)+pt.sup.p-1Φ(e.sub.z1(t),t)+(p+t.sup.p)Φ(e.sub.z2(t),t) that is, the deviation function about the output control parameter u.sub.1(t) is obtained;
(46) for the roll angle ϕ(t), in order to reach a target angle ϕ.sub.T(t), first defining an error function e.sub.ϕ1=ϕ(t)−ϕ.sub.T(t), such that we can obtain ė.sub.ϕ1={dot over (ϕ)}(t)−{dot over (ϕ)}.sub.T(t); since the solution is in an angle layer, according to the finite-time varying-parameter differential neurodynamics design method, we can obtain ė.sub.ϕ1(t)=−γ(t)Φ(e.sub.ϕ1(t),t),
(47)
by substituting the error function e.sub.ϕ1(t) and ė.sub.ϕ1(t) into the equation ė.sub.ϕ1(t)=−γ(t)Φ(e.sub.ϕ1(t)t), we can obtain
{dot over (ϕ)}(t)−{dot over (ϕ)}.sub.T(t)+(t.sup.p+p)Φ(e.sub.ϕ1(t),t)=0, (7)
ϕ(t) will converge to the target angle ϕ.sub.T(t) in a super-exponential manner within finite time; since {umlaut over (ϕ)}(t) is known, it is necessary to solve the equation involving {umlaut over (ϕ)}(t); in order to obtain the equation involving {umlaut over (ϕ)}(t), the error function e.sub.ϕ2={dot over (ϕ)}(t)−{dot over (ϕ)}.sub.T(t)+(t.sup.p+p)Φ(e.sub.ϕ1(t),t) is set by the same method and ė.sub.ϕ2(t)={umlaut over (ϕ)}(t)−{umlaut over (ϕ)}.sub.T(t)+(p+t.sup.p)Φ(e.sub.ϕ1(t),t)+pt.sup.p-1Φ(e.sub.ϕ1(t),t),
(48)
by substituting the above equations of e.sub.ϕ2(t) and ė.sub.ϕ2(t) into ė.sub.ϕ2(t)=−γ(t)Φ(e.sub.ϕ2(t),t), the following function can be obtained:
{umlaut over (ϕ)}(t)−{umlaut over (ϕ)}.sub.T(t)+(p+t.sup.p)((e.sub.ϕ1(t),t)+φ(e.sub.ϕ2(t),t)+pt.sup.p-1Φ(e.sub.ϕ1(t),t)=0 (8)
when equation (8) is established, the velocity layer {dot over (ϕ)}(t) will converge to {dot over (ϕ)}.sub.T(t) within finite time in a super-exponential manner, according to which the deviation function can be considered
E.sub.ϕ={umlaut over (ϕ)}(t)−{umlaut over (ϕ)}.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.ϕ1(t),t)+Φ(e.sub.ϕ2(t),t)+pt.sup.p-1Φ(e.sub.ϕ1(t),t) (9)
when the aerial vehicle reaches a target state, according to the dynamics model equation, the deviation function can be converted into
(49)
wherein
(50)
that is, the deviation function about the output control parameter u.sub.2(t) is obtained; for the pitch angle θ(t), in order to reach a target angle θ.sub.T(t), first defining an error function e.sub.θ1=θ(t)−θ.sub.T(t), such that we can obtain ė.sub.θ1={dot over (θ)}(t)−{dot over (θ)}.sub.T(t); since the solution is in an angle layer, according to the finite-time varying-parameter differential neurodynamics design method, we can obtain ė.sub.θ1(t)=−γ(t)Φ(e.sub.θ1(t),t),
(51)
by substituting the error function e.sub.θ1(t) and ė.sub.θ1(t) into the equation ė.sub.θ1(t)=−γ(t)Φ(e.sub.θ1(t),t), we can obtain
{dot over (ϕ)}(t)−{dot over (θ)}.sub.T(t)+(t.sup.p+p)Φ(e.sub.θ1(t),t)=0, (11)
(52) θ(t) will converge to the target angle θ.sub.T(t) in a super-exponential manner within finite time; since {umlaut over (θ)}(t) is known, it is necessary to solve the equation involving {umlaut over (θ)}(t); in order to obtain the equation involving {umlaut over (θ)}(t), the error function e.sub.θ2={dot over (θ)}(t)−{dot over (θ)}.sub.T(t)+(t.sup.p+p)Φ(e.sub.θ1(t),t) is set by the same method
(53) and ė.sub.θ2(t)={umlaut over (θ)}(t)−{umlaut over (θ)}.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.θ1(t),t)+pt.sup.p-1Φ((e.sub.θ1(t),t)
(54)
by substituting the above equations of e.sub.θ2(t) and ė.sub.θ2(t) into ė.sub.φ2(t)=−γ(t)Φ(e.sub.φ2(t),t), the following function can be obtained:
{umlaut over (θ)}(t)−{umlaut over (θ)}.sub.T(t)+(p+t.sup.p)(e.sub.θ1(t),t)+Φ(e.sub.θ2(t),t)+pt.sup.p-1Φ(e.sub.θ1(t),t)=0 (12)
when equation (12) is established, {dot over (θ)}(t) will converge to {dot over (θ)}.sub.T(t) within finite time in a super-exponential manner, according to which the deviation function is considered
E.sub.θ(t)={umlaut over (θ)}(t)−{umlaut over (θ)}.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.θ1(t),t)+Φ(e.sub.θ2(t),t)+pt.sup.p-1Φ(e.sub.θ1(t),t) (13)
when the aerial vehicle reaches a target state, according to the dynamics model equation, the deviation function can be converted into
(55)
wherein
(56)
that is, the deviation function about the output control parameter u.sub.3(t) is obtained;
(57) for the yaw angle ψ(t), in order to reach a target angle ψ.sub.T(t), first defining an error function e.sub.ψ1=ψ(t)−ψ.sub.T(t), such that we can obtain ė.sub.ψ1={dot over (ψ)}(t)−{dot over (ψ)}.sub.T(t); since the solution is in an angle layer, according to the finite-time varying-parameter differential neurodynamics design method, we can obtain, ė.sub.ψ1(t)=−γ(t)Φ(e.sub.ψ1(t),t),
(58)
by substituting the error function e.sub.ψ1(t) and ė.sub.ψ1(t) into the equation ė.sub.ψ1(t)=−γ(t)Φ(e.sub.ψ1(t),t), we can obtain
{dot over (ψ)}(t)−{dot over (ψ)}.sub.T(t)+(t.sup.p+p)Φ(e.sub.ψ1(t),t)=0, (15)
ψ(t) will converge to the target angle ψ.sub.T(t) in a super-exponential manner within finite time; since {umlaut over (ψ)}(t) is known, it is necessary to solve the equation involving {umlaut over (ψ)}(t); in order to obtain the equation involving {umlaut over (ψ)}(t), the error function e.sub.ψ2={dot over (ψ)}(t)−{dot over (ψ)}.sub.T(t)+(t.sup.p+p)Φ(e.sub.ψ1(t),t) is set by the same method and
(59)
by substituting the above equations of e.sub.ψ2(t) and ė.sub.ψ2(t) into ė.sub.φ2(t)=−γ(t)Φ(e.sub.φ2(t),t), the following function can be obtained:
{umlaut over (ψ)}(t)−{umlaut over (ψ)}.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.ψ1(t),t)+Φ(e.sub.ψ2(t),t)+pt.sup.p-1Φ(e.sub.ψ1(t),t)=0 (16)
when equation (16) is established, the velocity layer {dot over (ψ)}(t) will converge to {dot over (ψ)}.sub.T(t) within finite time in a super-exponential manner, according to which the deviation function can be considered
E.sub.ψ(t)={umlaut over (ψ)}(t)−{umlaut over (ψ)}.sub.T(t)+(p+t.sup.p){dot over (Φ)}(e.sub.ψ1(t),t)+Φ(e.sub.ψ2(t),t)+pt.sup.p-1Φ(e.sub.ψ1(t),t) (17)
when the aerial vehicle reaches a target state, according to the dynamics model equation, the deviation function can be converted into
(60)
wherein
(61)
that is, the deviation function about the output control parameter u.sub.4(t) is obtained;
(62) wherein, in step S4, the step of designing the finite-time varying-parameter convergence differential neural network solver according to the obtained system parameter deviation function of the finite-time varying-parameter convergence differential neural network about the output control parameters u.sub.1˜u.sub.4, respectively, specifically comprises:
(63) for the z-axis height z(t), by using the finite-time varying-parameter convergence differential neural network design method, designing Ė.sub.z(t)=−γ(t)Φ(E.sub.z(t),t), and substituting equation (6) and its derivative Ė.sub.z(t)={dot over (a)}.sub.z(t)u.sub.1(t)+a.sub.z(t){dot over (u)}.sub.1(t)+{dot over (b)}.sub.z(t), so that an implicit dynamics equation of the finite-time varying-parameter convergence differential neural network can be obtained:
a.sub.z(t){dot over (u)}.sub.1(t)=−({dot over (a)}.sub.z(t)u.sub.1(t)+{dot over (b)}.sub.z(t)+γ(t)Φ(E.sub.z(t),t)) (19)
the position z(t) and ż(t) will converge to a target z.sub.T(t) and ż.sub.T(t), respectively, in a super-exponential manner within finite time;
(64) for the roll angle ϕ(t), according to the finite-time varying-parameter convergence differential neurodynamics design method, designing Ė.sub.ϕ(t)=−γ(t)Φ(E.sub.ϕ(t),t), and substituting equation (10) and its derivative
(65)
so that an implicit dynamics equation of the finite-time varying-parameter convergence differential neural network can be obtained:
(66)
the roll angle ϕ(t) and {dot over (ϕ)}(t) will converge to a target ϕ.sub.T(t) and {dot over (ϕ)}.sub.T(t), respectively, in a super-exponential manner within finite time;
(67) for the pitch angle θ(t), according to the finite-time varying-parameter convergence differential neurodynamics design method, designing Ė.sub.θ(t)=−γ(t)Φ(E.sub.θ(t),t), and substituting equation (14) and its derivative
(68)
so that an implicit dynamics equation of the finite-time varying-parameter convergence differential neural network can be obtained:
(69)
the pitch angle θ(t) and {dot over (θ)}(t) will converge to a target θ.sub.T(t) and {dot over (θ)}.sub.T(t), respectively, in a super-exponential manner within finite time; and
(70) for the yaw angle ψ(t), according to the finite-time varying-parameter convergence differential neurodynamics design method, designing Ė.sub.ψ(t)=−γ(t)Φ(E.sub.ψ(t),t), and substituting equation (18) and its derivative
(71)
so that an implicit dynamics equation of the finite-time varying-parameter convergence differential neural network can be obtained:
(72)
the pitch angle ψ(t) and {dot over (ψ)}(t) will converge to a target ψ.sub.T(t) and {dot over (ψ)}.sub.T(t). respectively, in a super-exponential manner within finite time; and
(73) solving the synthesized control parameters u.sub.1˜u.sub.4 which is the control parameters corresponding to the flight demand of the aerial vehicle, according to equations (19), (20), (21) and (22), obtaining the neural network equations of the control parameters u.sub.1˜u.sub.4 respectively as follows:
(74)
(75) and performing different output control assignments with the solved control parameters u.sub.1(t)˜u.sub.4(t) according to the structure of and the number of motors of different rotor aerial vehicles.
(76) According to the control parameters u.sub.1˜u.sub.4 obtained in the above-mentioned neural network solving process, with regard to structures and motor numbers of different aerial vehicles, each motor is controlled through corresponding motor control parameter assignment, thus completing the motor control parameter assignment and motor control in the flow chart. According to the above steps, the invention can be achieved.
(77) To sum up, the invention firstly acquires real-time flight orientation and attitude data of the multi-rotor unmanned aerial vehicle through sensors thereof, and analyzes and processes kinematic problems of the aerial vehicle correspondingly through an airborne processor to establish a dynamics model of the aerial vehicle; then, designs a finite-time varying-parameter convergence differential neural network solver for the dynamics model of the multi-rotor aerial vehicle according to a finite-time varying-parameter convergence differential neurodynamics design method; next, solves output control parameters of motors of the aerial vehicle through the finite-time varying-parameter convergence differential neural network solver using the acquired real-time orientation and attitude data of the aerial vehicle; and finally, transmits results to speed regulators of the motors of the aerial vehicle to control the motion of the unmanned aerial vehicle. Based on the finite-time varying-parameter convergence differential neurodynamics method, the invention can approximate the correct solution of the problem in a quick, accurate and real-time way, and can well solve a variety of time-varying problems such as matrix, vector, algebra and optimization.
(78) The above-described embodiments are preferred embodiments of the invention; however, the embodiments of the invention are not limited to the above-described embodiments, and any other change, modification, replacement, combination, and simplification made without departing from the spirit, essence, and principle of the invention should be an equivalent replacement and should be included within the scope of protection of the invention.