CN108151746B - Improved label real-time airway re-planning method based on multi-resolution situation mapping - Google Patents
Improved label real-time airway re-planning method based on multi-resolution situation mapping Download PDFInfo
- Publication number
- CN108151746B CN108151746B CN201711441037.8A CN201711441037A CN108151746B CN 108151746 B CN108151746 B CN 108151746B CN 201711441037 A CN201711441037 A CN 201711441037A CN 108151746 B CN108151746 B CN 108151746B
- Authority
- CN
- China
- Prior art keywords
- resolution
- situation
- risk
- wavelet
- representing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 44
- 238000013507 mapping Methods 0.000 title claims abstract description 16
- 238000001514 detection method Methods 0.000 claims abstract description 10
- 238000005457 optimization Methods 0.000 claims description 16
- 238000000354 decomposition reaction Methods 0.000 claims description 13
- 238000004364 calculation method Methods 0.000 claims description 5
- 230000006835 compression Effects 0.000 claims description 4
- 238000007906 compression Methods 0.000 claims description 4
- 230000014509 gene expression Effects 0.000 claims description 4
- RZVHIXYEVGDQDX-UHFFFAOYSA-N 9,10-anthraquinone Chemical compound C1=CC=C2C(=O)C3=CC=CC=C3C(=O)C2=C1 RZVHIXYEVGDQDX-UHFFFAOYSA-N 0.000 claims description 3
- 238000013461 design Methods 0.000 claims description 3
- 238000009826 distribution Methods 0.000 claims description 2
- 238000010276 construction Methods 0.000 claims 1
- 238000011426 transformation method Methods 0.000 claims 1
- 230000006870 function Effects 0.000 description 17
- 230000008569 process Effects 0.000 description 6
- 238000013459 approach Methods 0.000 description 4
- 239000003795 chemical substances by application Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000003860 storage Methods 0.000 description 3
- 230000002457 bidirectional effect Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000007429 general method Methods 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000032823 cell division Effects 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 108010052322 limitin Proteins 0.000 description 1
- 238000007726 management method Methods 0.000 description 1
- 239000003550 marker Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 230000037361 pathway Effects 0.000 description 1
- 238000007781 pre-processing Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 238000010845 search algorithm Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000004800 variational method Methods 0.000 description 1
- 239000013598 vector Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
- G01C21/20—Instruments for performing navigational calculations
Landscapes
- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Automation & Control Theory (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Traffic Control Systems (AREA)
- Radar Systems Or Details Thereof (AREA)
Abstract
The invention belongs to the technical field of unmanned aerial vehicle systems, and discloses an improved label real-time airway re-planning method based on a multi-resolution situation map. The situation mapping method is used for counting the average operation time of about 305 milliseconds under a low-power-consumption embedded computing platform. On the basis of drawing, an improved label setting method is provided for generating the lowest detection/damage risk route under multiple constraints of oil consumption, endurance and the like on line. The statistical average operation time is about 25 milliseconds under the low-power-consumption embedded computing platform, and the method has a good application prospect in an avionics system with limited computing resources.
Description
Technical Field
The invention is oriented to the technical field of unmanned aerial vehicle systems, and can also be applied to the field of other robots. Specifically, multi-resolution wavelet compression is adopted to build a global situation map on line, and an improved label setting method is adopted to carry out on-line real-time route re-planning.
Background
The improvement of the autonomous capability of an unmanned aerial vehicle (or a robot) is a continuously pursued target in the field of intelligent robots. At present, a widely used unmanned aerial vehicle system mostly makes a flight route thereof through a ground station operator or a ground station computer system, and uploads the flight route to an airplane for execution. Recently, the development of an autonomous system supporting technology enables an unmanned system to have basic autonomous obstacle avoidance and automatic planning capabilities. However, the technical level still needs to be continuously improved, and a system is required to automatically generate a flight route by automatically utilizing the information of the airborne sensor and the airborne computing unit, so that the task response capability in a dynamic environment is improved. The high-autonomous unmanned aerial vehicle system can utilize all airborne available information to autonomously plan a flight route, improve the environment response capability and reduce the burden of ground station operators. The system should avoid obstacles or threats in a specific time window and reach a specified target position to execute a task.
The flight route planning is used as the basic capability of the autonomous unmanned aerial vehicle flight management system, is not only the basic capability of the unmanned aerial vehicle system, but also the important standard for measuring the autonomous level of the unmanned aerial vehicle system. High-level unmanned aerial vehicle routing techniques require that the aircraft be able to make on-line, real-time routing based on global and ambient aircraft-perceived situations. The air route needs to consider a global task target and local obstacle avoidance and threat avoidance capacity, so that the detection probability or the killing probability of a threatened/target is reduced to the maximum extent, and the airplane can be guided to approach to a final target. Meanwhile, the calculation resources and the storage resources distributed to the autonomous system components by the airborne avionic system are limited, and how to dynamically generate the air routes in real time and efficiently under the constraint condition of calculation performance is the key for restricting the availability of the system. The large range of the global situation and the high precision of the local situation bring irrecoverable burden to storage and calculation, and the contradiction between the global situation and the local situation needs to be solved, which is also a key technology to be solved urgently in the field.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: under the condition of low computing resources and low storage resources of an airborne system of the unmanned aerial vehicle, the flight path with low risk, low oil consumption and other performances can be autonomously generated in real time.
Aiming at the problems in the prior art, the invention mainly comprises two parts:
firstly, adopting multi-resolution compression to build a situation map: by analyzing situation distribution characteristics and strength and weakness of a task area of an unmanned aerial vehicle (or other robots), multi-resolution division is carried out on the global situation according to a plurality of critical distances, high-resolution situation mapping is carried out on an area closer to the airplane, and the airplane can carry out finer flight control; areas further away from the aircraft are mapped with a lower resolution, and the aircraft can be steered more coarsely. The situation mapping method can ensure the global characteristics of subsequent route planning, overcomes the defect that the classic rolling time domain control idea cannot meet the convergence, and can ensure that the airplane can accurately avoid obstacles and avoid flight control. The situation mapping method can meet the airborne real-time application requirement, and the statistical average operation time is about 305 milliseconds under a low-power-consumption embedded computing platform.
Secondly, multi-constraint minimum risk route optimization: on the basis of the first part of multi-resolution situation rasterization mapping, an improved label setting method is provided for generating the lowest detection/damage risk route under multiple constraints of oil consumption, time of flight and the like on line, the method avoids the defect that the planning problem analytic solution cannot be solved by a variational method, and the flight route is optimized by a discrete optimization approach. Under the condition that a plurality of radars are deployed by an opponent, a discrete optimization method is adopted to obtain a lowest risk route meeting various constraints such as oil consumption, endurance and the like. On the basis of multi-resolution situation mapping, a minimum risk route optimization problem with multiple constraints is described as a weight constraint shortest path problem, an improved label setting method is provided, the algorithm is tested through a series of standard example sets, the statistical average operation time is about 25 milliseconds under a low-power-consumption embedded computing platform, and the improved label setting method has a good application prospect in a avionic system with limited computing resources.
Drawings
FIG. 1 is a diagram of a fast lifting wavelet decomposition;
FIG. 2 is a multi-resolution situation map of an agent at a current location;
FIG. 3 is a multi-resolution cell division at different levels;
FIG. 4 is a recursive raster scan method for identifying individual cells;
FIG. 5 is a adjacency attribute for an individual cell;
FIG. 6 is a left search of adjacent individual cells;
FIG. 7 is a top left, top up search of adjacent individual cells;
FIG. 8 is a three-level multi-resolution cell adjacency diagram;
FIG. 9 is an unconstrained optimal trajectory for the case of two radars;
FIG. 10 is an optimal trajectory under length constraints for the case of two radars;
fig. 11 is a schematic diagram of an example network flow for solving the risk minimization problem.
Detailed Description
The invention is further described with reference to the following figures and detailed description.
Step one, multi-resolution situation map building and lifting wavelet transformation;
in the present invention, a world environment is assumedIncluding the space of obstaclesAnd an unobstructed configuration space F ═ W \ O. And performing multi-resolution decomposition on W by adopting wavelet transformation. By a basic elementary function phiJ,kAnd psiJ,kIs constructed by linear combination ofAs follows
Wherein phi isJ,k(x)=2J/2φ(2Jx-k) and psij,k=2j/2ψ(2jx-k). The choice of J depends on a low resolution or a rough approximation of f.Is wavelet function psij,k(x) To describe, function details that provide higher or finer resolution. In other words, when the function f is analyzed at the coarsest level (low resolution), only the most prominent features will appear. Adding finer levels (high resolution) means increasingPlus function f has more and more details. Thus (1) the resolution at different levels reveals the characteristics of f. Also ideally, both the scale function and the wavelet function have continuous support, i.e. they are non-zero only for a limited time interval. This allows the wavelet to capture local features of the function f.
Wherein, for the case of orthogonal wavelets, the approximation coefficients are given by
Detail coefficient of
Scale function
Wavelet function
The function is in [0,1 ]]Upper continuum, then, the scale function φ (x) and the wavelet function ψ (x) are 1/2 in lengthjInterval of (1)And also continuous therein. Similarly, a two-dimensional scale functionAnd having rectangular cellsWavelet function ofThe same is true.
Fast lifting wavelet transform provides fast decomposition of functions at different resolution levels, twice the speed of classical wavelet transform. It builds the wavelet directly in the time domain, avoiding the fourier analysis process. In addition, the fast lifting wavelet transform integer arithmetic can greatly reduce the calculation cost. This makes the fast lifting wavelet transform particularly suitable for processing data in low power microcontrollers. The use of the fast lifting wavelet transform also has the property of allowing adjacent cells to be directly related by wavelet coefficients, thereby eliminating the need for quadtree decomposition.
In fast lifting wavelet decomposition, as shown in fig. 1. Splitting the original signal a in a first blocknTwo disjoint sample sets containing odd and even indexed samples. Since the odd and even subsets are locally related to each other, each signal is boosted (double and original boosting or prediction and update) by the opposite signal after passing through the respective operators P and U. Finally, the result is normalized to a constant kaAnd kdRespectively obtaining an approximation coefficient and a detail coefficientn-1And dn-1。
Fast lifting wavelets have many advantages, such as faster computation speed (twice that of the usual discrete wavelet transform), in-situ computation of coefficients (saving memory), instantaneous inverse transform, broadening the generality of the irregularity problem, etc. In particular, the lifting scheme is suitable for many applications where the input data is integer samples.
Suppose W is [0,1 ]]×[0,1]Use of 2N×2NThe separation grid of (2). Resolution J of finest levelmaxBounded by N. The wavelet is more than or equal to J in resolution level JminDecomposition, as shown below
Then use a functionRepresenting the risk metric at (x, y), where M is a set of integer M different risk metric levels, defined as follows
For x e F, consider rm (x) as the spatial proximity of the agent to the obstacle, or the probability x e O.
At different levels of resolution Jmin≤j≤JmaxConstruct an approximation of W, in the sense that j is used for all points inside
Wherein,thereby meaning that a higher resolution is used for points close to the current position, and a different level of coarser resolution is used elsewhere depending on the distance from the current point. Thus, the further away from the current position, the coarser the representation of W, which is shown in fig. 2. J. the design is a squaremaxThe choice of (c) is determined by the requirement that all cells of the hierarchy can be resolved into free or obstacle cells. J. the design is a squareminAnd window span rjIs selected fromDetermined by the onboard computing resources.
The multi-resolution unit decomposition on W is as follows
Decomposing C for multi-resolution unitdOne topology G ═ V, E is assigned. The nodes belonging to the set V represent CdUnit ofThe edges in set E represent connectivity relationships between these nodes. The connectivity of graph G can be constructed directly from the wavelet coefficients. Equivalently, the adjacency list of G is computed directly from the wavelet coefficients obtained from the fast-lifting wavelet.
Because of the scale function of the two-dimensional waveletSum wavelet functionAssociated with the square cells, the corresponding approximation and non-zero detail coefficients encode the necessary information of the relevant cell geometry (size and position). The approximation coefficients are the average of the unit risk measures and the detail coefficients determine the size of each unit. More specifically, consider a case at j0Hierarchical unitDimension ofIs positioned asIf the cell is associated with a non-zero approximation coefficientAssociated while in range j0≤j≤JmaxCorresponding detail coefficientAre all zero and the cell is said to be independent. Otherwise, the cell is marked as the parent cell and again at j0The +1 level is divided into four subunits. If a sub-unit cannot be further subdivided, it is classified as an independent unit. As shown in FIG. 3, the uppermost parent unit is at j0The +1 level is divided into three independent units, each with a non-zero approximation coefficient in quadrants I, II, and III. For quadrant IV, the cell is at j0The +2 level is further subdivided into four independent subunits.
Suppose that the risk metric function rm given the wavelet transform reaches JminAnd (4) hierarchy. The coarsest level of the unit dimension is set to Jmin. In fig. 4, the initial coarse grid is depicted on the left. The agent is located at x ═ x, y, and the high resolution is given by r. From coarse cellsInitially, cells of different resolution levels are distinguished by determining that the cells partially intersect or belong entirely to the set N (x, r). The unit being readily responsive to selection of a marker, e.g.To determine that the property is satisfied. If a cell needs to be subdivided into higher resolution cells, an inverse fast lifting wavelet transform is first performed on the current cell (local reconstruction) to recover at j0Four approximation coefficients and corresponding detail coefficients at level + 1. Then, the overlapping of each cell within the cell is checked using the raster scan method (zigzag search: I → II → III → IV). This process has been usedThe process is recursively repeated until the highest resolution level J is reachedmax. Figure 4 shows a recursive raster scan search. Once a cell is identified as independent, a node is assigned in graph G whose cost is an approximation coefficient representing the average risk metric in the cell. In addition, the detail coefficients associated with the current cell are all set to zero; this will provide the necessary connectivity information between the units.
After a cell is determined to be an independent cell, neighboring cells are searched to establish an adjacency with the current cell. Two units ciAnd cjIs contiguous ifi ≠ j, whereinPresentation Unit ciThe boundary of (2). For the case of square cells, this implies that two cells are only contiguous along the following eight directions: left, top, right, bottom and four diagonal directions. Following a recursive grid search with cell identification, a neighbor search requires a connection to be established between two cells that are identified as independent cells. Reviewing the left-to-right, top-to-bottom (zig-zag progression) grid search process, as shown in fig. 4, the direction of the adjacency search is limited: left, top and top right of the current cell. By doing so, half of the links (eight connections) are given to connect with the current cell, and the remaining links proceed as a recursive raster scan to the next cell to connect with the current cell. In addition, since units with different dimensions are processed, a general method needs to be designed to find the adjacency relation between the units.
FIG. 5 shows the basic search directions of subunits within a parent unit. The dotted arrow points towards the outer search area, i.e. the neighboring cells may be beyond the cell, while the solid arrow points towards the inner search area belong to the cell. In each search, the hierarchy of implicitly assumed neighboring cells may vary from parent cell to Jmax(external connection), or from the current cell to Jmax(internal connection).
The subunit inherits the search area from the present unit, whose search direction ends with one of the solid arrows in fig. 5. Fig. 6 illustrates such inherited properties. In FIG. 6 the current cell is selected asThe unit being a parent unitAlso becomes the topmost end unitA sub-unit of (1). Unit cellAt the uppermost notebook unitIn the fourth quadrant, pairSearch area of j0The +1 level inner search ends with the neighbor search attribute at left, top left and top search directions inherited to the cellsAfter determining the basic search direction, the neighbor search is optimized to find independent opposite cells that are adjacent to the current cell. Since the relative cell of the current cell may have different dimensions, the connection is established by examining the relative detail coefficients of the relative cell.
If the relative cell is not a separate cell, that is, if it is composed of finer cells, the adjacency search algorithm refines its search to a higher level. This refinement then forces a search for finer dimensions (hierarchies). The detail coefficients of the opposite cell are then examined to find the next finer cell adjacent to the current cell. For theUpper left search direction, as shown in FIG. 7(a), the search process initially checks the upper left cell located at the current cell by the corresponding detail coefficientIf and unitThe associated detail coefficient takes a non-zero value and the cell is not a separate cell. Subsequently, the unitSegmented, relative cell to current cell becomes independent neighbor cell search process at j0+2 level repetition. In fig. 7(a), since there is no other independent unit except for the shadow 1 in the upper left direction, a bidirectional connection is established between the current and opposite units.
Likewise, for the top search direction, two j0+3 levels and a j0The +2 level cell is considered independent and contiguous to the current cell. The bidirectional connection is correspondingly changed from the current unitAre connected to these adjoining units. Fig. 7(b) depicts this situation. Finally, fig. 8 shows an example of a graph structure resulting from a multi-resolution cell decomposition associated with wavelet coefficients. Without loss of generality, the node is located at the center of each unit. The solid line indicates the connection relationship between the cells.
The invention obtains a general method for optimally avoiding threatening route planning while satisfying the route distance (oil consumption) constraint, and particularly focuses on risks related to radar detection. Fig. 9 and 10 are the unconstrained optimal trajectory and the length constrained optimal trajectory, respectively, for the two radar cases. The curves in these figures correspond to a set of risk levels near the maximum in the radar field. The risk decreases when the aircraft leaves the radar and increases when the aircraft approaches.
To formulate a solution to optimize risk paths, there are the following assumptions:
(1) the horizontal airplane model, i.e., the position of the airplane, is considered to be on only one horizontal plane.
(2) Radar detection of an aircraft is independent of the heading and climb angle of the aircraft.
(3) The angle of rotation is independent of the track position.
(4) The admissible field of the aircraft trajectory is assumed to be one detection zone for all radar devices. That is, the aircraft is no further away from each radar device than the maximum detection range of the radar.
(5) The risk is quantified in terms of a risk index per unit length for any particular aircraft location. The simplified threat model assumes that the risk index r is proportional to the risk factor σ, and is reciprocal to the square of the aircraft position to radar position distance. The risk factor σ depends on the technical characteristics of the radar, such as maximum detection range, minimum detectable signal, transmission power of the antenna, antenna gain and wavelength of the radar energy. It can be assumed that all radar technology characteristics remain unchanged, so σ is assumed for the radar under such a risk factoriIs constant. Suppose thatIs the aircraft position (x, y) to the radar position (a)i,bi) Distance of (d), risk index r of trace point (x, y)iByIt is given. Although in the present invention we consider the risk to be the inverse of the square of the distance, this assumption is not crucial to the application of the development method. For example, the risk index may be expressed asWhich corresponds to a radar detection model of the reflected signal from the aircraft. In this case, the risk factor σiA Radar Cross Section (RCS) of the aircraft is defined.
(6) N radar devices at each point of allowable deviation domainIs evaluated as the sum of the risks per radar, e.g.
(7) The aircraft speed is assumed to be constant, so the time increment dt is linearly related to the unit length ds: ds is V0dt。
(8) For any particular aircraft location (x, y), the risk per unit length ds is calculated as the product of a risk index and a unit length, e.g.
(9) Risk accumulation R along pathway P is represented by the expression R (P) ═ PjPrds presents.
Based on model assumptions 1-9, the optimization problem in path length constraints is set forth in the following manner. N represents the number of radars, (a)i,bi) Indicating a radar position, whereinThe departure and destination of the airplane are respectively A (x)1,y1) And B (x)2,y2). The path P from a to B is associated with a combined risk r (P) and a total length l (P). Best path P*The length constraint l (P). ltoreq.l should be minimized*. The optimization problem is presented in the following equation
Wherein R (P) and l (P) are defined by the following expressions
Step two, discrete optimization solution;
to solve (12-14), analytical and discrete optimization methods should be considered. Under the condition of considering any radar number, the discrete optimization method provided by the invention can solve the problem of reducing the generation problem of the optimal risk path to the weight value constraint shortest path of the grid undirected graph in the length constraint. The weight constraint shortest path problem of the grid undirected graph can be effectively solved through a network flow optimization algorithm. However, the computation time of these algorithms is exponential to the accuracy of the predetermined optimal trajectory. We assume that the allowable deviation domain of the aircraft trajectory is an undirected graph G ═ (V, a), where V ═ 1. The trajectory (x (), y ()) is approximated by a path P in the graph G, where the path P is approximated by a series of nodes<j0,j1,...,jp>Definitions, e.g. j0=A,jpB and for all values of k from 1 to p, satisfies<jk-1,jk>E.g. A. To configure (12-14) to the network optimization problem, we determine its risk and trajectory length using discrete approximations for equations (13) and (14), respectively.
Wherein,is an arc<jk-1,jk>The length of (a) of (b),arc of representation<jk-1,jk>The risk index of (a). Suppose x (j)k) And y (j)k) Is node jkX and y coordinates of (2), arc lengthIs defined by the following expression
The risk index is determined as
When in useApproaching zero, the risk index has a limitIn the limit case where the temperature of the molten metal is too high,e.g. jk-1→jkIs provided withFormula (18) at point jkConsistent with the definition of risk index.
Fig. 11 illustrates an example network flow to solve the risk minimization problem. In the case of two radars, the polyline is a path in the area,<jk-1,jk>is an arc of this path. Two nodes jk-1And jkThe distance between them is the arc length Anddefine radar 1 to node j respectivelyk-1And jkThe distance of (c).
The values R (P) and l (P) are rearranged
Thus, each arc<jk-1,jk>e.A and its lengthAnd non-negative costThe correlation is defined in (17) and (19), respectively. Taking into account the valueAs the weights of the arcs, we denote the cost of path P by R (P), and l (P) denotes the total weight accumulated along path P. If the total weight l (P) is at most l, i.e., l (P) is less than l, then the path P is weighted.
Step three, solving the shortest path problem by improving a label setting method;
the weight constraint shortest path problem is expressed in the following way. It is desirable to find a feasible path P from point A to point B that minimizes the cost R (P)
Equation (22) is closely related to the time window shortest path problem and the resource constraint shortest path problem, and uses vectors of weights or resources instead of scalars. These problems are solved in a fleet generation method for time-windowed aircraft path problems and long-haul aircraft path problems. Algorithms for solving the weight constraint shortest path problem are divided into three major categories: a label setting algorithm based on a dynamic programming method, a scaling algorithm and an algorithm based on a Lagrange relaxation method. In the case of a positive weight, the label setting algorithm is most effective. The gradient optimization and cutting plane method is the core of the Lagrange relaxation algorithm, and is effective to solve the Lagrange dual problem of the weight constraint shortest path problem under the condition of one resource. The scaling algorithm uses two complete polynomial approximation schemes of cost-based scaling and rounding for the weight constrained shortest path problem. The first approach is a geometric binary search, while the second iteratively extends the path. To solve the weight constrained shortest path problem, we use an improved label setting method with preprocessing, defined by (22).
Claims (5)
1. An improved label real-time airway re-planning method based on a multi-resolution situation map is characterized by comprising two parts: firstly, adopting multi-resolution compression to build a situation map: performing multi-resolution division on the global situation by analyzing situation distribution characteristics and strength and weakness confrontation degree of the unmanned aerial vehicle task area and taking a plurality of critical distances as the basis; secondly, multi-constraint minimum risk route optimization: on the basis of drawing construction, an improved label setting method is provided for generating a path with the lowest detection/damage risk under the conditions of oil consumption and multi-constraint during navigation on line; under the condition that a plurality of radars are deployed by an opponent, obtaining a lowest risk route meeting various constraints such as oil consumption, endurance and the like by adopting a discrete optimization method; the constraint of the oil consumption is distance constraint, and the lowest risk route meeting the oil consumption constraint is obtained by adopting a discretization method:
wherein σiRepresents a risk factor, diRepresenting the distance of the drone position from the radar position,is an arc<jk-1,jk>The length of (a) of (b),arc of representation<jk-1,jk>For x (j)k) And y (j)k) Is node jkX and y coordinates of (2), arc lengthIs defined by the following expression:
the risk index is determined as:
wherein,denotes x (j)k) And x (j)k-1) The included angle between the radar and the position connecting line of the radar,represents node jk-1The distance to the radar location is determined,represents node jkDistance to radar location;
the step of adopting multi-resolution compression to perform situation mapping comprises the following steps:
in the world environment W ═ 0,1]×[0,1]Whereinincluding the space of obstaclesAnd barrier-free configuration space F ═ W \ O, using 2N×2NThe finest level of resolution JmaxTaking N as boundary, wavelet is more than or equal to J in resolution level JminDecomposition, as follows:
wherein N represents the boundary corresponding to the finest resolution, J represents the resolution level of the grid, JminRepresenting the minimum resolution level of the grid, f (x, y) representing the function of wavelet decomposition in a separate grid, k, l representing the position information of level cells in the wavelet function, aJ,k,lRepresenting the approximation coefficient, phiJ,k,l(x, y) represents a scale function of a two-dimensional wavelet,the detail coefficients are shown in the form of,a wavelet function representing a two-dimensional wavelet;
the function of the risk metric at (x, y) is expressed as rm:where M is a set of different risk metric levels of integer M, defined as follows:
for x e F, rm (x) as the spatial proximity of the drone to the obstacle, or the probability x e;
at different levels of resolution Jmin≤j≤JmaxConstructing an approximation of W, j for all points inside, yields:
wherein, N (x)0,rj) Representing an approximate set of W, x0Indicates the current position, rjThe span of the window is represented by,representing the window span corresponding to the maximum resolution, rJminRepresenting a window span corresponding to the minimum resolution;higher resolution is used for points close to the current position, the farther away from the current position, the coarser the representation of W, JmaxIs determined by the requirement that all elements of this hierarchy can be resolved into free or obstacle elements; j. the design is a squareminAnd window span rjIs determined by on-board computing resources;
the multi-resolution unit decomposition on W is as follows:
wherein,is 1/2j×1/2jDimensional unitThe union of (a) and (b),is thatDimensional unitThe union of (a) and (b),is thatDimensional unitA union of (1);
decomposing C for multi-resolution unitdAnd assigning a topological graph G-V, E to obtain a situation graph.
2. The improved label real-time airway re-planning method based on multi-resolution situation mapping of claim 1, wherein: the multi-resolution division of the global situation refers to high-resolution situation mapping of an area close to the airplane, the airplane can conduct finer flight control, low-resolution situation mapping of an area far away from the airplane is conducted, and the airplane can conduct coarser direction guiding.
3. The improved label real-time airway re-planning method based on multi-resolution situation mapping of claim 2, wherein: the method for performing multi-resolution division on the global situation reduces the calculation cost by utilizing a fast lifting wavelet transformation method for establishing wavelets in a time domain, realizes fast decomposition on different levels of resolution, allows adjacent cells to directly pass through a structure represented by wavelet coefficients, and does not need to use quadtree decomposition.
4. The improved label real-time airway re-planning method based on multi-resolution situation mapping of claim 3, wherein: on the basis of multi-resolution situation mapping, a dynamic programming method-based improved label setting method is adopted, and the problem of route optimization under the condition of multiple constraints is solved.
5. The improved label real-time airway re-planning method based on multi-resolution situation mapping of claim 1, wherein: under the condition of meeting various constraints of oil consumption, time of flight and the like, a flight path with the lowest detected/killed risk is optimized and calculated by adopting a discrete optimization method, and the problem that a plurality of radar conditions are deployed by an opponent is solved.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201711441037.8A CN108151746B (en) | 2017-12-27 | 2017-12-27 | Improved label real-time airway re-planning method based on multi-resolution situation mapping |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201711441037.8A CN108151746B (en) | 2017-12-27 | 2017-12-27 | Improved label real-time airway re-planning method based on multi-resolution situation mapping |
Publications (2)
Publication Number | Publication Date |
---|---|
CN108151746A CN108151746A (en) | 2018-06-12 |
CN108151746B true CN108151746B (en) | 2020-11-10 |
Family
ID=62462503
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201711441037.8A Active CN108151746B (en) | 2017-12-27 | 2017-12-27 | Improved label real-time airway re-planning method based on multi-resolution situation mapping |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN108151746B (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108594645B (en) * | 2018-03-08 | 2021-02-19 | 中国人民解放军国防科技大学 | Planning method and system for single-station multi-unmanned aerial vehicle distribution and flight route |
CN112729308B (en) * | 2020-12-24 | 2024-05-03 | 广州融赋数智技术服务有限公司 | Unmanned aerial vehicle rapid track planning method under multi-constraint condition |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20100235082A1 (en) * | 2006-06-20 | 2010-09-16 | Navitime Japan Co., Ltd. | Route search system, route search server, terminal, and route search method |
CN101236245A (en) * | 2008-01-24 | 2008-08-06 | 上海交通大学 | Wavelet domain multi- sensor Correction Weighted optimal information integration method |
CN102622653B (en) * | 2012-02-27 | 2014-10-01 | 北京航空航天大学 | Multi-resolution path planning method for micro unmanned aerial vehicle under influence of wind field |
CN102880186B (en) * | 2012-08-03 | 2014-10-15 | 北京理工大学 | flight path planning method based on sparse A* algorithm and genetic algorithm |
CN104536442B (en) * | 2014-12-11 | 2017-02-01 | 西北工业大学 | Underwater vehicle path planning method based on dynamic planning |
CN106323295B (en) * | 2016-08-29 | 2019-04-19 | 中国船舶重工集团公司第七0九研究所 | A kind of aircraft under the dangerous meteorological condition based on weather radar data for communication changes boat method |
CN106441308B (en) * | 2016-11-10 | 2019-11-29 | 沈阳航空航天大学 | A kind of Path Planning for UAV based on adaptive weighting dove group's algorithm |
CN106979784B (en) * | 2017-03-16 | 2020-01-03 | 四川大学 | Non-linear track planning based on hybrid pigeon swarm algorithm |
-
2017
- 2017-12-27 CN CN201711441037.8A patent/CN108151746B/en active Active
Also Published As
Publication number | Publication date |
---|---|
CN108151746A (en) | 2018-06-12 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Yao et al. | Optimal UAV route planning for coverage search of stationary target in river | |
Zheng et al. | The obstacle detection method of uav based on 2D lidar | |
KR102414307B1 (en) | 3D map change area update system and method | |
CN116954233A (en) | Automatic matching method for inspection task and route | |
CN114330509B (en) | Method for predicting activity rule of aerial target | |
CN108151746B (en) | Improved label real-time airway re-planning method based on multi-resolution situation mapping | |
CN112466103A (en) | Aircraft flight threat evolution early warning method, device, equipment and storage medium | |
Kan et al. | Extreme learning machine terrain-based navigation for unmanned aerial vehicles | |
Sun et al. | Roads and Intersections Extraction from High‐Resolution Remote Sensing Imagery Based on Tensor Voting under Big Data Environment | |
Quin et al. | Approaches for efficiently detecting frontier cells in robotics exploration | |
CN114510072A (en) | Multi-unmanned aerial vehicle path planning method, terminal and medium based on evolution migration optimization | |
Wu et al. | A non-rigid hierarchical discrete grid structure and its application to UAVs conflict detection and path planning | |
Alasmari et al. | Improved metaheuristics with deep learning based object detector for intelligent control in autonomous vehicles | |
Pan et al. | Data-driven time series prediction based on multiplicative neuron model artificial neuron network | |
Xie et al. | Similarity search of spatiotemporal scenario data for strategic air traffic management | |
US11610119B2 (en) | Method and system for processing spatial data | |
CN115830578B (en) | Article inspection method and device and electronic equipment | |
Jung et al. | Enabling operational autonomy for unmanned aerial vehicles with scalability | |
Chung | On probabilistic search decisions under searcher motion constraints | |
CN114217641B (en) | Unmanned aerial vehicle power transmission and transformation equipment inspection method and system in non-structural environment | |
Wu et al. | Efficient box approximation for data-driven probabilistic geofencing | |
Xiao et al. | UAV 3-D path planning based on MOEA/D with adaptive areal weight adjustment | |
Yang et al. | An optimization-based selection approach of landing sites for swarm unmanned aerial vehicles in unknown environments | |
Hu et al. | A non-uniform quadtree map building method including dead-end semantics extraction | |
Peng et al. | An autonomous Unmanned Aerial Vehicle exploration platform with a hierarchical control method for post‐disaster infrastructures |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |