CN113655805A

CN113655805A - Graph search driving mode based on extended spiral line

Info

Publication number: CN113655805A
Application number: CN202110574589.6A
Authority: CN
Inventors: 李松; 杨付先; 潘雁坤; 靳鹏昭; 陈晓东; 李俊峰; 董创业; 李楠; 刘志强; 李洋; 郭敏; 司蓉蓉; 陈维蛇; 高少辰
Original assignee: Shaanxi Changling Electronic Technology Co ltd
Current assignee: Shaanxi Changling Electronic Technology Co ltd
Priority date: 2021-05-26
Filing date: 2021-05-26
Publication date: 2021-11-16

Abstract

The invention proposes a graphic search driving mode based on an extended helix, which mainly solves the problems of complex input parameters, low efficiency, incomplete search area, and easy to miss the best search and rescue opportunity when performing search and rescue in the prior art. The implementation scheme is: According to the principle that the aircraft can turn by controlling the bank angle, first, set the four input parameters of the starting position δ, the initial radius χ, the linear increase rate ξ and the turning direction λ; then, according to the standard control laws respectively. and the aircraft turning radius formula to calculate the bank angle α and the additional bank angle β; finally, according to the new bank angle γ=α+β, the aircraft is controlled to realize the circular flight mode with increasing radius r=χ+ξ×dt, where dt is Program cycle period. The invention has simple input parameters, high efficiency, wide search coverage, can effectively avoid or reduce casualties, meet the use requirements of search and rescue, and can be used in airborne navigation systems.

Description

Graph search driving mode based on extended spiral line

Technical Field

The invention belongs to the technical field of navigation, search and rescue, and particularly relates to a graph search driving mode which can be used for an airborne navigation system.

Background

The number of marine accidents is increasing. In order to search the specific position of people falling into water or encountering difficulty, an airplane is used for searching in a certain area range, and after a target is searched, a helicopter or a lifeboat is dispatched to rescue the person encountering difficulty.

In order to improve the success rate of maritime search and rescue in China, a search guiding airplane is firstly used for searching, after a target is found, a dyeing bomb is thrown in an area near the target, the specific position of the target of a standby helicopter set is informed, and subsequent rescue is carried out.

When the search guidance aircraft executes a search task, the aircraft flies to the approximate drowning point from the current position, and then the extended search is carried out by taking the approximate drowning point as the center. The time is saved during the expansion search, the drowning person is ensured not to have life danger, the search density is required to be low, and a wide area covered by a roughly drowning point as a center can be ensured. Therefore, a navigation system for searching for a guided aircraft needs to perform automatic search in a certain driving manner.

The aircraft usually flies by adopting a flight path driving mode, a plurality of flight points are required to be preset before flying to form a flight path, each flight point sequentially flies according to the flight path when the aircraft is driven, and because a plurality of search and rescue flight points are difficult to be preset when the aircraft is searched and guided, the navigation search is carried out according to the flight path driving mode, the annular search of a specific area cannot be realized, and the optimal search and rescue opportunity is missed due to narrow search range and incomplete search area.

Disclosure of Invention

The invention aims to provide a search driving mode based on an expanded spiral line graph aiming at the defects of the prior art so as to realize annular search of a specific area, expand the search range, grasp the optimal search and rescue opportunity and reduce or avoid casualties.

The technical idea of the invention is as follows: according to the principle that the larger the inclination angle of the airplane is, the smaller the turning radius is, a spiral flight driving mode is established through graphic parameter setting and real-time adjustment of the inclination angle, the navigation driving requirement of the search and guidance airplane during searching is met, namely, the spiral search graphics are expanded through the initial position, the initial radius, the linear increasing speed and the turning direction, and the airplane is controlled to comprehensively complete expanded searching in the water falling area. The specific implementation scheme comprises the following steps:

according to the above thought, the search driving method based on the extended spiral line pattern of the present invention is characterized by including the following three stages:

the first stage is flying according To the flight path, namely after the airplane receives an expansion spiral line instruction, the current position is taken as a starting point From, the input parameter initial position is taken as a To point, a flight segment is drawn, and the airplane is controlled To fly To the position near an initial circle determined by the initial position and the input parameter initial radius according To the flight segment;

the second stage is to adjust the flight, namely after the aircraft flies to the vicinity of the initial circle, the inclination angle alpha of the aircraft is adjusted in real time by the changes of the yaw distance and the track angle error by utilizing the standard control law according to the input parameters of the initial radius, the linear increasing rate and the turning direction, so that the aircraft smoothly transits from the flight path to the extended flight;

and in the third stage, extended flight is carried out, namely after the airplane flies to the initial circle, the flight radius r of the airplane is adjusted in real time by utilizing the linear increasing rate of the input parameter, the inclination angle additional term beta is calculated and added to the inclination angle alpha, and the airplane realizes extended flight by the adjusted inclination angle gamma which is alpha + beta.

Compared with the prior art, the invention has the following advantages:

1. simple input parameter

When the traditional flight route flight mode is adopted to realize the area search, a plurality of waypoints are required to be input firstly, each waypoint comprises longitude, latitude and magnetic difference information, if the number of the input waypoints is large, the input is complex, if the number of the input waypoints is small, the coverage area is small, careless omission easily occurs, the method can realize the area search only by inputting four parameters, and the optimal search and rescue opportunity is easy to ensure.

2. Wide coverage and high search efficiency

The traditional air route searching mode is difficult to realize annular searching, and the area which can be covered by the annular searching is the largest within the same searching and rescuing flight time.

3. The control of the airplane is relatively stable

The invention calculates the inclination angle by continuously iterating and expanding the radius, has short iteration period and is only the cycle period of a program, so the change of the inclination angle is smooth, the stable and smooth control of the airplane can be realized, and the adverse reaction of search and rescue personnel is reduced.

Drawings

FIG. 1 is a schematic view of an existing airline flight;

FIG. 2 is a navigation parameter definition diagram;

figure 3 is a schematic diagram of the helix flight of the present invention.

Detailed Description

Embodiments of the present invention are described in further detail below with reference to the accompanying drawings.

The invention is based on the flight path driving, uses the set spiral line parameters to carry out iterative operation, calculates various navigation parameters and carries out annular spiral extended flight.

Referring to fig. 1, in the conventional flight path driving, a flight path is composed of a plurality of waypoints, usually no more than 25 waypoints, an aircraft sequentially flies according to the flight path composed of the planned waypoints, and in this flight mode, more input information is required for each waypoint, new waypoints need to be continuously input during search and rescue, the operation is complex, and the search and rescue opportunity is easily missed, so that the flight path driving is not suitable for search and rescue.

After the navigation computer completes the binding of the flying starting point and the editing of the flight route to be flown, the navigation computer needs to set the navigation parameters according to the simple airborne navigation theory.

Referring to fig. 2, the navigation parameters are defined and set as follows:

taking the current flying point as a From point and taking the flight point A as a To point, and calculating the distance eta and the predicted track angle DTK parameters of the two points;

after the airplane leaves the ground, the navigation computer utilizes the ground speed V and the airspeed epsilon of the airplane to calculate a track angle TRK, a track angle error TAE, a distance DTA, a yaw distance XTD, a distance to fly DTG and an azimuth angle BAFT,

these parameters are defined as follows:

the predicted track angle DTK is as follows: the included angle between the connecting line flight segment From the departure point From To the To point of the airplane and the true north;

the track angle TRK is as follows: the included angle between the flight path of the airplane and the true north;

the track angle error TAE: predicting an included angle between a flight path and an actual flight path for the airplane;

the yaw distance XTD: the vertical distance between the actual position of the airplane and a preset air route;

the distance DTA: distance of the aircraft to the to waypoint;

the distance to fly DTG: the projection distance of the distance DTA on the predicted track DTK is obtained;

the azimuth angle BAFT: the azimuth angle from the current position of the aircraft to point to.

Various angles in the airborne navigation use the due north direction as a reference, and various angle values are calculated by clockwise rotation.

Referring to fig. 3, the flight mode of the present example is an extended helix pattern driving mode, which is divided into three phases of flight, flight adjustment and extended flight, and is specifically implemented as follows:

first phase, flight of the flight path:

and after receiving the expansion spiral line instruction, the navigation computer takes the current position of the airplane as a From point, takes the input initial position delta as a To point, draws a flight section, and controls the airplane To fly To the position near an initial circle determined by the initial position delta and the initial radius x according To the flight path flight mode of the prior art.

The second stage, adjusting flight:

entering a flight adjusting stage after the flight of the air route is finished, wherein the flight adjusting stage is a transition stage of the air route flight and the extended flight and is realized as follows:

2.1) calculating the tilt angle alpha of the airplane in real time by using the input initial radius theta, the linear increasing rate xi and the turning direction lambda according to a standard control law:

2.1.1) calculating the yaw distance XTD and the track angle error TAE respectively:

XTD＝DTA-χ

TAE＝DTK-TRK

wherein χ is an initial radius, DTA is a distance between the current position of the airplane and an input initial position δ, DTK is a predicted track angle, DTK is BAFT + 90-theta during right turning, DTK is BAFT-90-theta during left turning, BAFT is an azimuth angle of the airplane, and theta is an arctangent of a ratio result of an input linear increasing rate ξ and a ground speed V; the TRK is a flight path angle calculated by a navigation computer according to the existing airborne navigation theory by utilizing the current ground speed V and the airspeed epsilon of the airplane, the linear increasing rate xi is input with different values according to specific practical application, and the linear increasing rate xi is set but not limited to be 5 nautical miles per hour in the example;

2.1.2) calculating the inclination angle alpha of the airplane according to the current ground speed V, the yaw distance XTD and the track angle error TAE of the airplane:

α＝C₁×XTD+C₂×V×TAE，

wherein, C₁、C₂Are two different constants, C₁17 °/hai, C₂0.0034 hr/haili;

2.2) the airplane performs adjustment flight according to the calculated inclination angle alpha;

and a third stage, expanding the flight:

after the adjustment flight is finished, the airplane enters an extended flight stage, and the extended radius r is firstly calculated according to a linear increasing rate xi in a program loop:

r＝χ+ξdt

wherein χ is an initial radius, dt is a cycle period of the program;

then, calculating an additional inclination angle beta according to the current ground speed V, the gravity acceleration g and the expansion radius r of the airplane:

finally, the additional tilt angle β is added to the tilt angle α, constituting a new tilt angle γ: gamma-alpha + beta

And controlling the airplane to carry out extended flight according to the new inclination angle gamma, namely, taking the input initial position delta as the center, taking the input turning direction lambda as the rotating direction, and carrying out annular mode search flight with the radius increasing continuously according to the input initial radius chi and the linear increasing rate xi.

While the invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. a kind of graphic search driving mode based on expanding helix, is characterized in that, comprises following three stages:

The first stage is to fly according to the route, that is, after the aircraft receives the extended helix command, it uses the current position as the starting point From, and the initial position of the input parameters as the To point, draws a segment, and controls the aircraft to fly according to the segment to from the initial point. Near the initial circle determined by the position and the initial radius of the input parameters;

The second stage is to adjust the flight, that is, after the aircraft flies to the vicinity of the initial circle, according to the input parameters of the initial radius, linear increase rate and turning direction, using standard control laws, real-time adjustment through changes in yaw distance and track angle error The inclination angle α of the aircraft makes the aircraft smoothly transition from route flight to extended flight;

The third stage is to carry out extended flight, that is, after the aircraft flies to the initial circle, the flight radius r of the aircraft is adjusted in real time using the linear increase rate of the input parameters, the additional term β of the inclination angle is calculated, and it is added to the inclination angle α. , the aircraft realizes extended flight with the adjusted inclination angle γ=α+β.

2. driving mode according to claim 1 is characterized in that, during the adjustment flight of the second stage, the inclination angle α of the aircraft is adjusted according to the following formula in the standard control law:

α=C ₁ ×XTD+C ₂ ×V×TAE

Among them, C ₁ and C ₂ are two constants with different values, V is the current ground speed of the aircraft, XTD is the difference between the current position of the aircraft and the initial radius, and TAE is the expected track angle DTK and track angle TRK The estimated track angle DTK is determined by the current azimuth of the aircraft, the linear increase rate and the turning direction, and the track angle TRK is calculated according to the changing position of the aircraft.

3. driving mode according to claim 1, is characterized in that, during the extended flight of the 3rd stage, utilize the parameter linear increase rate of input to adjust the flight radius r of aircraft in real time, carry out according to the following formula:

r=χ+ξ×dt

Among them, χ is the initial radius of the input, ξ is the linear increase rate of the input, and dt is the cycle period when the program is running.

4. driving mode according to claim 1 is characterized in that, during the extended flight of the third stage, the aircraft inclination angle additional term β is calculated according to the following formula:

Where V is the ground speed, g is the acceleration of gravity, and r is the radius value after each iteration of the program.