RU2749990C1 - Method for correcting the formed configuration of the route of an unmanned gliding aircraft - Google Patents

Abstract

FIELD: unmanned gliding aircrafts.

SUBSTANCE: invention relates to a method for correcting the formed configuration of the route of an unmanned gliding aircraft (UAV). To correct the formed route configuration, the route is set by reference points in the form of a set of geodetic coordinates, the values ​​of the rotation angles are determined at the reference points, and if, when compared with the permissible values ​​of the angles set in advance and specified in the table in the function of the flight range, a difference is found that causes a violation of the specified technical restrictions on the controllers parameters of the UAV, then, according to the rules of spherical trigonometry, the problematic reference point is iteratively shifted to small distances with a decrease in the rotation angle value of the route to an acceptable one. EFFECT: correction of the formed UAV route is provided in case of non-fulfillment of technical restrictions at reference points.

1 cl, 2 dwg, 1 tbl

Description

The invention relates to the field of guidance of unmanned gliding vehicles (UAVs) and can be used in the operation of such aircraft.

Closest to this invention is the "Method of control of an unmanned gliding aircraft" (RU 2654238, 2018), based on the following basic provisions:

1. The UAV has the ability to autonomously control the magnitude and direction of the aerodynamic lift by purposefully changing the angle of aerodynamic roll ϕ and the angle of attack α.

2. The movement of the UAV along the route specified by the set of reference points M _j (j = 1, ..., N) is carried out by sequential guidance to these points.

The UAV route is selected on the map of the earth's surface in places where, for some reason, a change in the direction of the UAV movement is required, and is set by the control points of the route in the form of a set of geodetic coordinates B _j , L _j . In accordance with the total length of the route, the initial conditions are determined (the initial values of the speed V ₀ and the height H ₀ ), as a function of the distance from the starting point, the heights of the intermediate control points H _j are calculated.

Before the flight, the formed route and the corresponding reference trajectory are checked for the possibility of implementation, i.e. to meet all technical constraints, and above all, on transverse overloads. The control over the feasibility of the given reference trajectories of the aircraft is carried out by the method of computer flight simulation. By simulating a UAV flight with control according to the method described in the analogue, it is possible to control the feasibility of a given route, but only up to the reference point at which it is found that the constraints are not met. Pointing to the next reference point fails and you need to change the specified route and check it again for feasibility. The analog method does not determine how to correct the route. If there are several problematic control points on the route, the process of monitoring the feasibility of the route is delayed, since its correction has to be carried out by “trial and error”.

The objective of the present invention is to introduce changes into the process of monitoring the feasibility of the UAV route, which will make it possible to correct the formed UAV route if the technical constraints at the reference points are not met.

The technical result is achieved by the fact that the UAV route is set by reference points in the form of a set of geodetic coordinates, when the UAV route is formed at the reference points, the values of the turning angles are determined and, if, when compared with the permissible values of the angles set in advance and specified in the table as a function of the flight range, a difference is found that causes violation of the specified technical constraints on the control parameters of the UAV, then, according to the rules of spherical trigonometry, the problematic reference point is iteratively shifted over short distances with a decrease in the angle of rotation of the route to an acceptable value.

Correction of the formed configuration of the UAV route includes the following operations:

,

) при экстремальных значениях управляющих поперечных перегрузок определяется зависимость допустимых углов поворота траектории от удаленности БПЛА от начальной точки траектории. Составляются таблицы вида (таблица 1):1. In advance, at the stage of ballistic design of the UAV by means of multiple modeling of typical trajectories (with initial conditions - given values of altitude and speed

,

) at extreme values of the control transverse overloads, the dependence of the permissible trajectory rotation angles on the distance of the UAV from the starting point of the trajectory is determined. Tables of the form are compiled (table 1):

=30000 м и

=4500 м/сDependence of the permissible angle of rotation of the trajectory γ _add on the distance of the UAV from the initial point of the trajectory at

= 30,000 m and

= 4500 m / s

2. When forming a specific UAV route on the sphere of the Earth's average radius (Fig. 1), using the formulas of spherical trigonometry, the angles γ _i between the links of the UAV route being formed are determined. Using dependence (1), problematic reference points are determined at which the inequality

and, therefore, in flight at the reference point S _j (B _j , L _j , H _j ), the lateral overload constraint cannot be satisfied.

3. Correction of the position of problem control points of the route is carried out according to the algorithm, which ensures the reduction of angles γ _i (D) to acceptable values.

The essence of the proposed method for correcting the initially specified configuration of the UAV route is to create dependence (1) and use it to identify problem control points of the route and to create an algorithm for changing the coordinates of individual control points to values that ensure the fulfillment of lateral overload constraints in flight.

The algorithm for changing the coordinates of the problem GCP includes:

1. Solution by the formulas of spherical trigonometry of spherical triangles PM _j-1 M _j and PM _j M _{j + 1} (Fig. 1) with the definition of the angle γ _i as the angle between the sides of triangles with a common vertex M _j . All the necessary data to determine the sides and angles of these triangles are available - these are the coordinates B _j , L _{j of the} points M _j-1 , M _j and M _{j + 1} . Transformations of geodetic coordinates to spherical coordinates are known, but not presented here. The algorithm for solving this problem includes:

a) the angles α ₁ and β _{1 are} determined from the triangle PM _j-1 M _j (Fig. 2);

b) the external angle to the angle β ₁ is determined λ = π - β ₁ ;

c) the angle β _{2 is} determined from the triangle PM _j M _{j + 1} ;

d) the angle γ _j = β ₂ - λ is determined.

2. An iterative procedure for displacing the point M _j along the normal to the line M _j-1 M _{j + 1} at small distances in order to change (decrease) the value of the angle γ _i to an acceptable value

determined according to table 1.

The iterative procedure, assuming that the link of the route M _j-1 M ' _j = M _j-1 M _j = const, includes:

, его увеличение в случае, если B_j > B_j-1, и уменьшение в обратном случае;a) changing the angle α ₂ by a small angle

, its increase if B _j > B _j-1 , and decrease in the opposite case;

b) determination of the side PM ' _{j of the} spherical triangle PM _j-1 M' _j by the theorem of cosines of the sides:

where Ф _j is the angular measure of the link M _j-1 M _j , the value of which is determined from the triangle PM ' _j M _{j + 1} by the theorem of sines:

sinФ _j = sin (L _j -L _j-1 ) ⋅cos B _j-1 / sinβ ₁ ;

c) determining the angle ΔL ' _j = L _j - L' _j from the expression for the cosine of the side M _j-1 M ' _{j of the} spherical triangle PM _j-1 M' _j :

d) determining the coordinates of the point M ' _j :

expression (4) implies

e) further all calculations of p.p. 1, 2 are carried out cyclically until condition (3) is satisfied.

The algorithm presented in p. 1, 2, in addition to the fact that it provides the formation of the UAV route, it can be included in the onboard algorithm for monitoring the feasibility of each next turn of the trajectory, eliminating the effects of disturbances in the UAV movement.

Claims (1)

A method for correcting the formed configuration of the route of an unmanned gliding aircraft (UAV), which consists in the fact that the UAV route is set by control points in the form of a set of geodetic coordinates, characterized in that when the UAV route is formed, the values of the rotation angles are determined at the control points, and if, when compared with the admissible values of the angles set in advance and set in the table as a function of the flight range reveal a difference that causes a violation of the specified technical restrictions on the control parameters of the UAV, then, according to the rules of spherical trigonometry, the problematic reference point is iteratively shifted to small distances with a decrease in the angle of rotation of the route to an acceptable value.

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