CN110377044B - Finite time height and attitude tracking control method of unmanned helicopter - Google Patents

Abstract

The invention discloses a finite time height and attitude tracking control method of an unmanned helicopter, which comprises the following steps: firstly, considering the flapping models of a main rotor and an aileron, and establishing a height and attitude comprehensive model; then, constructing a finite time interference observer to estimate unknown time-varying interference, and acquiring an interference estimation value; then, designing a height and posture composite anti-interference tracking controller based on the observed interference estimation value by combining an exponentiation integration method; and finally, selecting proper controller gain and observer gain according to a design rule to realize the limited time tracking of the height and the attitude. The invention improves the accuracy, rapidity and anti-interference of the height and attitude closed-loop tracking system of the unmanned helicopter.

Description

Finite time height and attitude tracking control method of unmanned helicopter

Technical Field

The invention relates to a finite time height and attitude tracking control method of an unmanned helicopter, belonging to the technical field of flight control of unmanned helicopters.

Background

In recent years, unmanned helicopters have attracted much attention due to their unique advantages, such as vertical take-off and landing, low-altitude flight, flight in narrow and complex environments such as mountainous areas and buildings. Based on these advantages, unmanned helicopters are widely used for aerial photography, rescue, detection, and other tasks. However, unmanned helicopters are a highly nonlinear, under-actuated, strongly coupled system. Furthermore, its flight performance is susceptible to disturbances, such as wind gusts. Therefore, designing a high-performance flight controller becomes a challenging research topic.

At present, the control method of the unmanned helicopter system mainly comprises linear control and nonlinear control. Traditional control methods are based primarily on linearized mathematical models. However, the linearization of the model occurs at the equilibrium point, and the controller performance will be greatly degraded when the system state deviates from the equilibrium point. In order to overcome the defects of the linear control method, more and more nonlinear control methods are used for unmanned helicopter control, such as sliding mode control, backstepping control, model prediction control and the like. However, these methods only guarantee asymptotic stability of the closed loop system.

The document (i.a. raptis, k.p. valavanis, w.a. Moreno, a novel nonlinear feedback Control system for using the rotation matrix, IEEE Transactions on Control Systems Technology, vol.19, No.2,2011,465 and 473) proposes to introduce a nested saturation feedback function in the backstepping design, and to Control the attitude by using the structural characteristics of the rotation matrix, so that the helicopter tracks the predetermined position and yaw reference trajectory. The document (K.Yan, Q.Wu, M.Chen, Robust adaptive backstepping Control for autonomous helicopter with flapping dynamics, 201713 th IEEE International reference on Control & Automation (ICCA 2017, pp.1027-1032.) proposes a Robust adaptive backstepping controller of an unmanned autonomous helicopter with flapping dynamics, and designs a nonlinear disturbance observer to estimate external unknown disturbance. The controller designed by the article deals with the influence of external unknown interference. But only demonstrates that all signals of the closed loop system are consistently bounded and stable.

Disclosure of Invention

In consideration of the characteristics of high nonlinearity, under-actuation and strong coupling of the unmanned helicopter system, the invention provides a finite time height and attitude tracking control method of the unmanned helicopter, which is a composite anti-interference height and attitude finite time tracking control method combining a finite time interference observer technology and an exponentiation integration method, so that the unmanned helicopter system has finite time tracking performance and strong anti-interference performance.

The invention adopts the following technical scheme for solving the technical problems:

the invention provides a finite time height and attitude tracking control method of an unmanned helicopter, which comprises the following steps:

the method comprises the following steps: considering a waving model and time-varying interference, and establishing a height and posture comprehensive model;

the height and attitude comprehensive model is as follows:

wherein: Θ ═ η^T z]^T，

U_z＝-C_θC_φT_mM is the mass of the unmanned helicopter, g, eta ═ phi theta psi]^T∈R³Z and V_zRespectively representing the gravity acceleration, the attitude, the height and the linear velocity, omega, corresponding to the height of the unmanned helicopter under an inertial coordinate system_b＝[p q r]^T∈R³Representing the attitude angular velocity of the unmanned helicopter under a body coordinate system, wherein p, q and r are respectively a rolling angular velocity, a pitch angular velocity and a yaw angular velocity;

is an attitude vector transformation matrix, phi, theta and psi are respectively the roll angle, the pitch angle and the yaw angle of the unmanned helicopter, S_ψDenotes sin psi, S_φ、C_φ、C_θ、S_θAnd T_θDenotes sin phi, cos theta, sin theta and tan theta, respectively, and J ═ diag { I_xx I_yy I_zzIs an inertia matrix, I_xx,I_yy,I_zzThe rotational inertia of the unmanned helicopter around the x axis, the y axis and the z axis respectively; a and b are respectively the longitudinal direction and the transverse direction of the main rotorWaving angles, respectively, from the longitudinal input signal delta_lonAnd a transverse input signal delta_latControlling; a. the_lonAnd B_latEffective gains, A, for controlling the input signal to the longitudinal and transverse flapping angles of the main rotor, respectively_cAnd B_dCoupling coefficients of the main rotor and the ailerons, C and d being longitudinal and transverse flapping angles of the ailerons, respectively, C_lonAnd D_latEffective gains for controlling input signals to the longitudinal and lateral flap angles of the aileron, respectively; tau is_fAnd τ_sAre all time constants; tau is_bThe moment generated for the main rotor and the tail wing,

T_mand T_tThe resultant force generated by the main rotor and the resultant force generated by the empennage are respectively generated; c_ma,C_mbAre physical parameters related to the stiffness of the main rotor; z is a radical of_mAnd z_tThe z-axis axial distance, x, from the main rotor and the tail rotor rotation axis to the center of gravity of the helicopter_tThe x-axis axial distance from the empennage rotating shaft to the center of gravity of the helicopter; q_m＝C_MQT_m ^3/2+D_MQTotal moment generated for rotation of main rotor, C_MQAnd D_MQAre all normal numbers related to the generation of reactive torque of the main rotor; d ═ Jd [ [ (Jd)_ω)^T md_vz]^T,d_ω＝[d_p d_q d_r]^TRepresenting time-varying disturbances acting on the attitude channel of the unmanned helicopter system, d_vzRepresenting time-varying disturbances acting on the vertical direction speed path of the unmanned helicopter system, d_p、d_q、d_rRespectively, the interference acting on the channels of the roll angle, the pitch angle and the yaw rate;

step two: constructing a finite time interference observer to estimate unknown time-varying interference, and acquiring an interference estimation value;

let p be χ₁,q＝χ₂,r＝χ₃,V_z＝χ₄,d_p＝d₁,d_q＝d₂,d_r＝d₃,d_vz＝d₄To n orderInterference d that can be minimized_iThere is a known Lipschitz constant L_iAnd > 0, the finite time disturbance observer is:

wherein, when i is 1,2,3,4, λ_i,jFor a positive observer gain, j is 0,1,2,

are respectively chi_i、d_i、

Is determined by the estimated value of (c),

sgn (. cndot.) is a sign function, y₁＝[T_mbz_m-T_tz_t+C_mbb-qr(I_zz-I_yy)]/I_xx+d₁，y₂＝[T_maz_m+C_maa-pr(I_xx-I_zz)]/I_yy+d₂，y₃＝[T_tx_t-Q_m-pq(I_yy-I_xx)]/I_zz+d₃,y₄＝(mg-C_θC_φT_m)/m+d₄；

Step three: designing a height and attitude composite anti-interference finite time tracking controller based on the interference estimated value obtained in the step two, and carrying out interference compensation and height and attitude tracking;

the height and attitude composite anti-interference finite time tracking controller comprises:

wherein α ═ α₁/α₂∈(1,2)，α₁、α₂Are all positive odd numbers, theta_ref＝[φ_ref θ_ref ψ_ref z_ref]^T，φ_ref、θ_refAnd psi_refRespectively desired roll, pitch and yaw angles, z_refA desired height; e.g. of the type₁＝Θ-Θ_ref＝[e_φ e_θ e_ψe_z]^T，e_φFor roll angle tracking error, e_θFor pitch angle tracking error, e_ψFor yaw angle tracking error, e_zIs the height tracking error; e.g. of the type_a＝a-a_refAnd e_b＝b-b_refErrors of longitudinal and transverse waving angles, a_refAnd b_refRespectively desired longitudinal and transverse flapping angles, k, of the main rotor_1,1,k_1,2,k_1,3,k_1,4,k_2,1,k_2,2,k_2,3,k_2,4,k₃,k₄Is the controller gain;

step four: and selecting observer gain and controller gain, and realizing the finite time stability of the unmanned helicopter height and attitude closed-loop tracking system through the height and attitude composite anti-interference finite time tracking controller.

As a further technical solution of the present invention, the observer gain and the controller gain selected in step four are:

k_1,1＞0,k_1,2＞0,k_1,3＞0,k_1,4＞0；

order to

h_1,1＝(2-1/α)2^(1-1α)k_1,1 ^1+α，h_1,2＝(2-1/α)2^(1-1α)k_1,2 ^1+α，h_1,3＝(2-1/α)2^(1-1α)k_1,3 ^1+α，h_1,4＝(2-1/α)2^(1-1α)k_1,4 ^1+α)，

Then k is_2,1，k_2,2，k_2,3，k_2,4Satisfy k_2,1/h_1,1-ρ_1,1＞0，k_2,2/h_1,2-ρ_1,2＞0，k_2,3/h_1,3-ρ_1,3＞0，k_2,4/h_1,4-ρ_1,4＞0，k₃,k₄Satisfy k₃＞0,k₄＞0，i＝1,2,3,4,j＝0,1,2,λ_i,j＞0。

As a further technical scheme of the invention, a in the third step_refAnd b_refAre respectively:

as a further technical solution of the present invention, the observation error system corresponding to the observer in the step two is:

wherein e is_i,0＝χ_i-ξ_i,0,e_i,1＝d_i-ξ_i,1,

Technical effects

Compared with the prior art, the technical scheme provided by the invention has the following technical effects:

the designed high-order differential finite time disturbance observer can be used for observing various forms of disturbance such as constant disturbance, slope disturbance, high-order disturbance, sinusoidal disturbance and the like and various derivatives thereof, enables an observation error to be converged to 0 in finite time, and has universality.

And (II) the finite time observer technology and the power integration method are combined, and the designed composite anti-interference finite time controller can effectively process the negative influence of interference on the system, so that the height and attitude tracking errors are converged to 0 in finite time.

And thirdly, the composite anti-interference finite time control technical idea provided by the invention is suitable for system control design in other technical fields, and has wide application prospect.

Drawings

FIG. 1 is a control block diagram of a closed loop system for altitude and attitude of an unmanned helicopter;

FIG. 2 is a flow chart of the steps of the solution;

FIG. 3 is a coordinate system diagram of the unmanned helicopter;

FIG. 4 is a plot of attitude and altitude tracking error responses, wherein (a) is roll angle, (b) is pitch angle, (c) is yaw angle, and (d) is altitude;

FIG. 5 is a plot of attitude and altitude actual position versus desired position, wherein (a) is roll angle, (b) is pitch angle, (c) is yaw angle, and (d) is altitude;

FIG. 6 is a plot of observed error response, where (a) is the disturbance for the roll rate channel, (b) is the disturbance for the pitch rate channel, (c) is the disturbance for the yaw rate channel, and (d) is the disturbance for the altitude rate channel;

FIG. 7 is a comparison graph of an actual disturbance value and an observed disturbance value, wherein (a) is a disturbance of a roll rate channel, (b) is a disturbance of a pitch rate channel, (c) is a disturbance of a yaw rate channel, and (d) is a disturbance of a altitude rate channel;

FIG. 8 is a graph showing the variation of control signals, wherein (a) is T_mAnd (b) is T_tAnd (c) is delta_lonAnd (d) is delta_lat。

Detailed Description

The technical scheme of the invention is further explained in detail by combining the attached drawings:

the method comprises the following steps: and sequentially calculating a 6-degree-of-freedom model, a flapping model and force and moment of the unmanned helicopter, and then comprehensively obtaining a height and attitude model considering interference.

(a) The unmanned helicopter model with 6 degrees of freedom is as follows:

wherein m represents the mass of the unmanned helicopter, g, P ═ x y z]^T∈R³、η＝[φ θ ψ]^T∈R³And V ═ V_xV_y V_z]^T∈R³Respectively representing it in an inertial coordinate systemAcceleration of gravity, position, attitude and linear velocity; omega_b＝[p q r]^T∈R³And f_b＝[f_x f_y f_z]^T∈R³、τ_b＝[τ_x τ_y τ_z]^T∈R³Respectively representing the attitude angular velocity, the force and the moment under the body coordinate system; p, q and r are respectively a rolling angular velocity, a pitching angular velocity and a yaw angular velocity. And a transformation matrix from the body coordinate system to the inertial coordinate system is defined as

Phi, theta and psi, respectively, the roll angle, pitch angle and yaw angle of the unmanned helicopter, S_ψ、C_ψ、S_φ、C_φ、C_θ、S_θAnd T_θDenoted sin ψ, cos ψ, sin φ, cos θ, sin θ and tan θ, respectively. Attitude vector transformation matrix

The pitch angle being maintained in normal flight

Therefore H is not singular. J ═ diag { I ═ I_x I_y I_zIs an inertia matrix, I_xx,I_yy,I_zzThe rotary inertia of the unmanned helicopter around the x, y and z axes.

(b) Waving model

The main rotor flap model is as follows:

the flap model is:

wherein, tau_f,τ_sAre all time constants, a, bLongitudinal and transverse flapping angles of the main rotor are respectively provided by a longitudinal input signal delta_lonAnd a transverse input signal delta_latAnd (5) controlling. A. the_lon,B_latFor controlling the effective gain of the input signal to the longitudinal and transverse flapping angles of the main rotor, A_c,B_dIs the coupling coefficient of the main rotor and the ailerons, C, d are the longitudinal and transverse flapping angles of the ailerons, C_lon,D_latTo control the effective gain of the input signal to the longitudinal and lateral flap angles of the aileron.

(c) Calculation of force and moment

Because a and b are very small, the requirements of sina ≈ a, sinb ≈ 1, cosa ≈ 1 and cosb ≈ 1 are met, and the force of the unmanned helicopter in the x and y directions is far less than the force in the z direction during height control, so that f and b are very small_b＝[0 0 -T_m]^TThe main rotor and the tail wing generate a moment of

T_m,T_tRespectively the resultant force generated by the main rotor and the resultant force generated by the empennage. C_ma,C_mbIs a physical parameter related to the stiffness of the main rotor. z is a radical of_m,z_tThe Z-axis axial distances from the main rotor and the tail wing rotating shaft to the center of gravity of the helicopter respectively; x is the number of_tThe x-axis axial distance from the empennage rotation axis to the center of gravity of the helicopter. Q_m＝C_MQ·T_m ^3/2+D_MQTotal moment generated for rotation of main rotor, C_MQ,D_MQIs a normal number related to the generation of the reaction torque of the main rotor.

(d) Height and attitude integrated model

Let Θ be ═ η^T z]^T，

U_z＝-C_θC_φT_m。

Considering the flapping dynamic characteristics of the main rotor and the ailerons, the height and attitude comprehensive model of the unmanned helicopter is established as follows:

wherein D ═ Jd [ (-)_ω)^T md_vz]^T,d_ω＝[d_p d_q d_r]^TRepresenting time-varying disturbances acting on the attitude channel of the unmanned helicopter system, d_vzRepresenting time-varying disturbances acting on the vertical direction speed path of the unmanned helicopter system, d_p、d_q、d_rRespectively, the disturbances acting on the channels of roll angle, pitch angle, yaw rate.

Step two: and designing a finite time interference observer to obtain an interference estimation value and a derivative estimation value thereof.

For convenience of illustration, let p ═ χ₁,q＝χ₂,r＝χ₃,V_z＝χ₄,d_p＝d₁,d_q＝d₂,d_r＝d₃,d_vz＝d₄. For differentiable d of n order_i(i ═ 1,2,3,4) has a known Lipschitz constant L_iAnd > 0, designing the following finite time disturbance observer:

description of the drawings: when i is 1,2,3,4,

are respectively chi_i,d_i,

Is estimated value, function

And sgn (·) is a standard sign function. y is₁＝[T_mbz_m-T_tz_t+C_mbb-qr(I_zz-I_yy)]/I_xx+d₁，y₂＝[T_maz_m+C_maa-pr(I_xx-I_zz)]/I_yy+d₂，y₃＝[T_tx_t-Q_m-pq(I_yy-I_xx)]/I_zz+d₃,y₄＝(mg-C_θC_φT_m)/m+d₄。λ_i,j(j ═ 0,1,2) is the positive observer gain to be designed.

The corresponding observation error system is:

wherein e is_i,0＝χ_i-ξ_i,0,e_i,1＝d_i-ξ_i,1,

Selecting proper observer gain lambda for observing error_i,j(j is 0,1,2), the observation error can be made in a finite time T₁Converging to zero. The finite time observer of the form of equation (5) is suitable for disturbances in the form of constant values, ramps, higher orders, sinusoids, etc.

Step three: and (4) applying the interference and derivative estimation values thereof obtained in the step two to feed-forward compensation, and designing a composite anti-interference height and attitude finite time tracking controller by combining a finite time observer technology and an exponentiation integration method to ensure that the height and attitude tracking errors have finite time convergence to 0.

Control signal T_m,T_t,δ_lon,δ_latThe specific form of (A) is as follows:

wherein α ═ α₁/α₂∈(1,2),α₁、α₂Is positive odd number, theta_ref＝[φ_ref θ_ref ψ_ref z_ref]^TTo a desired attitude and height, phi_ref、θ_refAnd psi_refRespectively desired roll, pitch and yaw angles, z_refA desired height; e.g. of the type₁＝Θ-Θ_ref＝[e_φ e_θ e_ψ e_z]^TTo track errors, e_φFor roll angle tracking error, e_θFor pitch angle tracking error, e_ψFor yaw angle tracking error, e_zIs the height tracking error; e.g. of the type_a＝a-a_ref,e_b＝b-b_refLongitudinal flap angle and transverse flap angle errors, respectively. a is_ref,b_refRespectively designed as follows:

k_1,1,k_1,2,k_1,3,k_1,4,k_2,1,k_2,2,k_2,3,k_2,4,k₃,k₄is the gain to be designed.

Step four: and selecting proper controller gain and observer gain according to a design rule to realize the finite time stability of the unmanned helicopter height and attitude closed-loop tracking system.

The observer gain and the controller gain selected in the fourth step are as follows:

k_1,1＞0,k_1,2＞0,k_1,3＞0,k_1,4＞0；

order to

h_1,1＝(2-1/α)2^(1-1/α)k_1,1 ^1+α，h_1,2＝(2-1/α)2^(1-1/α)k_1,2 ^1+α，h_1,3＝(2-1/α)2^(1-1/α)k_1,3 ^1+α，h_1,4＝(2-1/α)2^(1-1/α)k_1,4 ^1+α，

Then k is_2,1，k_2,2，k_2,3，k_2,4Satisfy k_2,1/h_1,1-ρ_1,1＞0，k_2,2/h_1,2-ρ_1,2＞0，k_2,3/h_1,3-ρ_1,3＞0，k_2,4/h_1,4-ρ_1,4＞0，k₃,k₄Satisfy k₃＞0,k₄＞0，i＝1,2,3,4,j＝0,1,2,λ_i,j＞0。

For height and attitude models with unknown disturbances, finite time stabilization, i.e. height tracking error and attitude tracking error, can be achieved if the controller is designed as in equations (7) to (10) for a finite time T₂Converging to zero.

In order to verify the effectiveness of the height and attitude limited time tracking control method proposed by the invention, a numerical simulation was performed with MATLAB.

Initial state of unmanned helicopter is eta₀＝[0.50.50.5]^Trad,z₀2m, the desired attitude angle and height η_ref＝[0.5sint 0.5sint 0.5sint]^Trad,z_ref5m, the interference expression is set to d₁＝2.5sin(0.3t+30),d₂＝1.2sin(0.5t+15),d₃＝1.8sin(0.2t+30),d₄1.8sin (0.9t + 15). Fig. 4 shows (a) to (d) that attitude and altitude tracking errors can be converged to 0 relatively quickly in the presence of disturbance, fig. 5 shows (a) to (d) that are graphs comparing actual positions of attitude and altitude with desired positions, fig. 6 shows (a) to (d) that track performance of the observation error system, and disturbance observation errors can be converged to 0 quickly and accurately, fig. 7 shows (a) to (d) that compare actual values of disturbance with observed values, and fig. 8 shows (a) to (d) that are graphs showing changes of control input signals. Simulation results show that the height and attitude composite anti-interference finite time tracking controller designed by the invention is effective.

The above embodiments are merely illustrative of the technical ideas of the present invention, and do not limit the scope of the present invention. It should be noted that any improvement made to the technical solution on the technical idea of the present invention belongs to the protection scope of the present invention.

Claims (4)

1. A finite time altitude and attitude tracking control method of an unmanned helicopter is characterized by comprising the following steps:

the method comprises the following steps: considering a waving model and time-varying interference, and establishing a height and posture comprehensive model;

the height and attitude comprehensive model is as follows:

wherein: Θ ═ η^T z]^T，

U_z＝-C_θC_φT_mM is the mass of the unmanned helicopter, g, eta ═ phi theta psi]^T∈R³Z and V_zRespectively representing the gravity acceleration, the attitude, the height and the linear velocity, omega, corresponding to the height of the unmanned helicopter under an inertial coordinate system_b＝[p q r]^T∈R³Representing the attitude angular velocity of the unmanned helicopter under a body coordinate system, wherein p, q and r are respectively a rolling angular velocity, a pitch angular velocity and a yaw angular velocity;

is an attitude vector transformation matrix, phi, theta and psi are respectively the roll angle, the pitch angle and the yaw angle of the unmanned helicopter, S_ψDenotes sin psi, S_φ、C_φ、C_θ、S_θAnd T_θDenotes sin phi, cos theta, sin theta and tan theta, respectively, and J ═ diag { I_xx I_yy I_zzIs an inertia matrix, I_xx,I_yy,I_zzThe rotational inertia of the unmanned helicopter around the x axis, the y axis and the z axis respectively; a and b are respectively the longitudinal and transverse flapping angles of the main rotor, and are respectively provided by a longitudinal input signal delta_lonAnd a transverse input signal delta_latControlling; a. the_lonAnd B_latEffective gains, A, for controlling the input signal to the longitudinal and transverse flapping angles of the main rotor, respectively_cAnd B_dCoupling coefficients of the main rotor and the ailerons, C and d being longitudinal and transverse flapping angles of the ailerons, respectively, C_lonAnd D_latEffective gains for controlling input signals to the longitudinal and lateral flap angles of the aileron, respectively; tau is_fAnd τ_sAre all time constants; tau is_bThe moment generated for the main rotor and the tail wing,

T_mand T_tThe resultant force generated by the main rotor and the resultant force generated by the empennage are respectively generated; c_ma,C_mbAre physical parameters related to the stiffness of the main rotor; z is a radical of_mAnd z_tThe z-axis axial distance, x, from the main rotor and the tail rotor rotation axis to the center of gravity of the helicopter_tThe x-axis axial distance from the empennage rotating shaft to the center of gravity of the helicopter; q_m＝C_MQT_m ^3/2+D_MQTotal moment generated for rotation of main rotor, C_MQAnd D_MQIs a normal number related to the generation of the reaction torque of the main rotor; d ═ Jd [ [ (Jd)_ω)^Tmd_vz]^T,d_ω＝[d_p d_q d_r]^TRepresenting time-varying disturbances acting on the attitude channel of the unmanned helicopter system, d_p、d_q、d_rRespectively, disturbances acting on the channels of roll, pitch and yaw rates, d_vzRepresenting time-varying interference acting on a vertical direction speed channel of the unmanned helicopter system;

step two: constructing a finite time interference observer to estimate unknown time-varying interference, and acquiring an interference estimation value;

let p be χ₁,q＝χ₂,r＝χ₃,V_z＝χ₄,d_p＝d₁,d_q＝d₂,d_r＝d₃,d_vz＝d₄For a negligible interference d of order n_iThere is a known Lipschitz constant L_iAnd > 0, the finite time disturbance observer is:

wherein, when i is 1,2,3,4, λ_i,jFor a positive observer gain, j is 0,1,2,

are respectively chi_i、d_i、

Is determined by the estimated value of (c),

sgn (. cndot.) is a sign function, y₁＝[T_mbz_m-T_tz_t+C_mbb-qr(I_zz-I_yy)]/I_xx+d₁，y₂＝[T_maz_m+C_maa-pr(I_xx-I_zz)]/I_yy+d₂，y₃＝[T_tx_t-Q_m-pq(I_yy-I_xx)]/I_zz+d₃,y₄＝(mg-C_θC_φT_m)/m+d₄；

Step three: designing a height and attitude composite anti-interference finite time tracking controller based on the interference estimated value obtained in the step two, and carrying out interference compensation and height and attitude tracking;

the height and attitude composite anti-interference finite time tracking controller comprises:

wherein α ═ α₁/α₂∈(1,2)，α₁、α₂Are all positive odd numbers, theta_ref＝[φ_ref θ_ref ψ_ref z_ref]^T，φ_ref、θ_refAnd psi_refRespectively desired roll, pitch and yaw angles, z_refA desired height; e.g. of the type₁＝Θ-Θ_ref＝[e_φ e_θ e_ψe_z]^T，e_φFor roll angle tracking error, e_θFor pitch angle tracking error, e_ψFor yaw angle tracking error, e_zIs the height tracking error; e.g. of the type_a＝a-a_refAnd e_b＝b-b_refErrors of longitudinal and transverse waving angles, a_refAnd b_refRespectively desired longitudinal and transverse flapping angles, k, of the main rotor_1,1,k_1,2,k_1,3,k_1,4,k_2,1,k_2,2,k_2,3,k_2,4,k₃,k₄Is the controller gain;

step four: and selecting observer gain and controller gain, and realizing the finite time stability of the unmanned helicopter height and attitude closed-loop tracking system through the height and attitude composite anti-interference finite time tracking controller.

2. The finite time altitude and attitude tracking control method of an unmanned helicopter of claim 1, wherein the observer gain and the controller gain selected in step four are:

k_1,1＞0,k_1,2＞0,k_1,3＞0,k_1,4＞0；

order to

h_1,1＝(2-1/α)2^(1-1/α)k_1,1 ^1+α，h_1,2＝(2-1/α)2^(1-1/α)k_1,2 ^1+α，h_1,3＝(2-1/α)2^(1-1/α)k_1,3 ^1+α，h_1,4＝(2-1/α)2^(1-1/α)k_1,4 ^1+α，

Then k is_2,1，k_2,2，k_2,3，k_2,4Satisfy k_2,1/h_1,1-ρ_1,1＞0，k_2,2/h_1,2-ρ_1,2＞0，k_2,3/h_1,3-ρ_1,3＞0，k_2,4/h_1,4-ρ_1,4＞0，k₃,k₄Satisfy k₃＞0,k₄＞0，i＝1,2,3,4,j＝0,1,2,λ_i,j＞0。

3. The finite time altitude and attitude tracking control method of an unmanned helicopter of claim 1, characterized by step three in a_refAnd b_refAre respectively:

4. the finite-time altitude and attitude tracking control method of the unmanned helicopter according to claim 1, wherein the corresponding observation error system of the observer in the second step is:

wherein e is_i,0＝χ_i-ξ_i,0,e_i,1＝d_i-ξ_i,1,

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