Unmanned aerial vehicle rescue full coverage search and rescue method and system

Abstract

The application discloses a UAV rescue full-coverage search and rescue method and system, which comprises the following steps: offsetting a search and rescue boundary inward by a distance to obtain a search and rescue area boundary offset line; judging whether the center of the area surrounded by the search and rescue area boundary offset line has a hole; when there is a hole, adopting annular slit mapping to map the area to a slit-containing annular ring through conformal slit mapping, and the boundary of the area is mapped into an inner and outer boundary of the annular ring and an internal circular-arc-shaped slit; when there is no hole, adopting disc-shaped slit mapping to map the area to a slit-containing disc through slit mapping, and the boundary of the area is mapped into an outer boundary of the disc and an internal circular-arc-shaped slit; obtaining an unequal division spiral line in the annular ring or disc image domain which does not intersect with the slit; and obtaining a spiral track on the original image after the inverse mapping of the conformal slit mapping of the unequal division spiral line is mapped back to the original image domain, searching along the search and rescue area boundary offset line, and checking a dangerous area which cannot be searched by the spiral track.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of unmanned aerial vehicle search and rescue, and more particularly relates to a method and system for full coverage search and rescue by unmanned aerial vehicle. BACKGROUND

[0002] The spiral trajectory search and rescue by unmanned aerial vehicle has the advantages of less discontinuity between trajectories, smooth turning, and trajectory adhesion to the search and rescue area boundary. Generating a shorter, smoother, and less discontinuous spiral trajectory is crucial for unmanned aerial vehicle search and rescue. However, for complex boundaries and areas with internal hazards that cannot be crossed, traditional spiral trajectory planning methods have problems such as inconsistent trajectory spacing, dramatic turning that can be optimized, and many discontinuities that need to be bridged. These problems result in frequent turning, longer search and rescue paths, and greater actuator motion impact, making it difficult for unmanned aerial vehicles to quickly and fully cover the search and rescue area, increasing the risk of the unmanned aerial vehicle and the person in distress.

[0003] Traditional spiral trajectory generation methods mainly include a method based on a medial axis tree, a method based on solving elliptic partial differential equations on a disk-shaped equivalent single-connected region or an annular equivalent two-connected region, and a method based on disk or annular conformal mapping. The above methods can directly generate spiral trajectories on single-connected or two-connected regions. For multi-connected regions containing islands, the above methods need to add boundaries to divide the multi-connected region into several single-connected or two-connected sub-regions, then generate independent spiral trajectories in each sub-region, and finally connect the spiral trajectories between sub-regions by bridging. However, the above approach adds sub-region boundaries, resulting in uneven spacing of spiral trajectories within the sub-regions, and a large number of bridges. When the sub-region boundary contains sharp corners, the path will also turn sharply near the corners, which has a negative impact on the unmanned aerial vehicle search and rescue, such as large motion impact, frequent turning, and long path. SUMMARY

[0004] To solve the above technical problems, the present application provides a method for full coverage search and rescue by unmanned aerial vehicle, comprising:

[0005] offsetting the search and rescue boundary inward by a distance to obtain a search and rescue region boundary offset line, determining whether the center of the region enclosed by the search and rescue region boundary offset line has a hole, when there is a hole, using annular slit mapping to map the region through conformal slit mapping to a circular ring containing a slit, the boundary of the region is mapped into the inner and outer boundaries of the circular ring and the internal circular arc-shaped slit, when there is no hole, using disk-shaped slit mapping to map the region through slit mapping to a circular disk containing a slit, the boundary of the region is mapped into the outer boundary of the circular disk and the internal circular arc-shaped slit;

[0006] The inverse mapping of the cluster of concentric circle lines on the annular or disc image domain mapped by the conformal slit is mapped back to the original image domain to obtain the isoparametric lines on the original image. The radii of the cluster of concentric circle lines are adjusted so that the maximum inscribed circle radius between adjacent isoparametric lines is a set value. On the annular or disc image domain, the concentric circles are gradually offset to adjacent concentric circles to obtain non-equidistant spiral lines. The offset speed is adjusted to avoid the intersection of the non-equidistant spiral lines with the slit in the image domain, and non-equidistant spiral lines that do not intersect with the slit in the annular or disc image domain are obtained.

[0007] The inverse mapping of the non-equidistant spiral lines mapped by the conformal slit is mapped back to the original image domain to obtain spiral trajectories on the original image. The dangerous areas that cannot be searched and rescued by the spiral trajectories are searched and rescued along the boundary offset lines of the search and rescue area.

[0008] Further, the boundary of the search and rescue area is determined by the boundary function, including:

[0009]

[0010] where B is the boundary function, M is the number of boundaries, L is the length of the trajectory, a is the transition adjustment factor, s is the arc length on the trajectory, μ′ i is the position where the ith transition occurs.

[0011] Further, obstacle avoidance is performed by setting the obstacle avoidance function, including:

[0012]

[0013] where O is the obstacle avoidance function, N is the number of obstacles, L is the length of the trajectory, s is the arc length on the trajectory, μ i is the mean of the ith Gaussian function, σ i is the ith standard deviation.

[0014] Further, the search and rescue trajectory is made smoother by setting the smoothness function, including:

[0015]

[0016] where S' is the smoothness function, k(s) is the curvature of the point on the trajectory with arc length s, v(s) is the speed of the point on the trajectory with arc length s, is the turning rate of the point on the trajectory with arc length s, is the acceleration of the point on the trajectory with arc length s, L is the length of the trajectory, β is the turning rate weight, γ is the speed weight, and δ is the acceleration weight.

[0017] Further, the search and rescue trajectory is made smoother by setting the smoothness function, including:

[0018]

[0019] where D is a distance function, N' is the number of points on the trajectory with arc length s, d i is the distance between the i-th point and the adjacent point on the trajectory with arc length s, is the average distance between points on the trajectory with arc length s.

[0020] The present application also proposes a UAV rescue full coverage search and rescue system, comprising:

[0021] The slit acquisition module is used to offset the search and rescue boundary inward by a distance to obtain a search and rescue boundary offset line, and to judge whether the center of the region surrounded by the search and rescue boundary offset line has a hole. When there is a hole, the region is mapped onto a circular ring containing a slit through conformal slit mapping by using ring-shaped slit mapping, and the boundary of the region is mapped into the inner and outer boundaries of the circular ring and the internal circular arc-shaped slit. When there is no hole, the region is mapped onto a circular disc containing a slit through slit mapping by using disc-shaped slit mapping, and the boundary of the region is mapped into the outer boundary of the circular disc and the internal circular arc-shaped slit.

[0022] The unequal division spiral line acquisition module is used to map the concentric circular line cluster on the circular ring or disc image domain back to the original image domain through inverse mapping of conformal slit mapping to obtain the isoparametric line on the original image. The radii of the concentric circular line cluster are adjusted so that the maximum inscribed circle radius between adjacent isoparametric lines is a set value. The concentric circles are gradually offset to adjacent concentric circles on the circular ring or disc image domain to obtain unequal distance spiral lines, and the offset speed is adjusted to avoid intersection between the unequal distance spiral lines and the slits in the image domain, thereby obtaining unequal division spiral lines in the circular ring or disc image domain that do not intersect with the slits.

[0023] The dangerous area investigation module is used to map the unequal division spiral lines back to the original image domain through inverse mapping of conformal slit mapping to obtain spiral trajectories on the original image. The spiral trajectories that cannot be searched and rescued are investigated along the search and rescue boundary offset line.

[0024] Further, the boundary function is used to judge the boundary of the search and rescue region, comprising:

[0025]

[0026] where B is a boundary function, M is the number of boundaries, L is the length of the trajectory, a is a transition adjustment factor, s is the arc length on the trajectory, μ' i is the position where the i-th transition occurs.

[0027] Further, the obstacle avoidance function is used for obstacle avoidance, comprising:

[0028]

[0029] Wherein, O is an obstacle avoidance function, N is the number of obstacles, L is the length of the trajectory, s is the arc length on the trajectory, μ i is the mean of the ith Gaussian function, σ i is the ith standard deviation.

[0030] Further, by setting the smoothness function to make the search and rescue trajectory smoother, comprising:

[0031]

[0032] Wherein, S' is the smoothness function, k(s) is the curvature of the point on the trajectory with arc length s, v(s) is the speed of the point on the trajectory with arc length s, is the turning rate of the point on the trajectory with arc length s, is the acceleration of the point on the trajectory with arc length s, L is the length of the trajectory, β is the turning rate weight, γ is the speed weight, and δ is the acceleration weight.

[0033] Further, by setting the spacing function to avoid excessive twists of the search and rescue trajectory, comprising:

[0034]

[0035] Wherein, D is the spacing function, N' is the number of points on the trajectory with arc length s, d i is the distance between the ith point on the trajectory with arc length s and the adjacent point, is the average distance between the points on the trajectory with arc length s.

[0036] Compared with the prior art, the above technical scheme conceived by the present application has the following beneficial effects:

[0037] 1. Compared with the existing spiral trajectory planning method, the present application no longer divides the multi-connected region into several sub-regions, but directly generates a spiral trajectory without bridging to approximately cover the entire region, which avoids the problem of a large number of bridging between sub-regions caused by sub-region division, and at the same time, since no additional sub-region boundary is added, the spiral trajectory path generated by this method is shorter and smoother, and the trajectory spacing is more consistent.

[0038] 2. The present application introduces a strategy for controlling the spacing of spiral trajectories based on the maximum inscribed circle, which can guarantee the upper limit of the spacing of spiral trajectories, avoid excessive or excessive path, and make the path have smaller redundant coverage rate under the premise of ensuring full coverage of the path.

[0039] 3. Connecting the spiral trajectory and the boundary offset after the boundary of the dangerous region as a whole solves the problem of incomplete coverage of the spiral trajectory, and also avoids the existence of discontinuity or sharp turning in the path. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 is a flow chart of embodiment 1;

[0041] Figure 2 is a conformal slit map of search area boundary and search area;

[0042] Figure 3 is a conformal slit map of search area boundary and search area;

[0043] Figure 4 is a conformal slit map of search area boundary and search area;

[0044] Figure 5 is a conformal slit map of search area boundary and search area;

[0045] Figure 6 is a conformal slit map of search area boundary and search area. DETAILED DESCRIPTION

[0046] In order to better understand the above technical solutions, the above technical solutions will be described in detail below in combination with the description of the drawings and specific embodiments.

[0047] The method provided by the application can be implemented in a terminal environment, which can include one or more of the following components: a processor, a storage medium and a display screen. The storage medium stores at least one instruction, which is loaded and executed by the processor to implement the method described in the following embodiments.

[0048] The processor can include one or more processing cores. The processor connects various parts in the entire terminal through various interfaces and lines, executes various functions of the terminal and processes data by running or executing instructions, programs, code sets or instruction sets stored in the storage medium, and calling data stored in the storage medium.

[0049] The storage medium can include random access memory (RAM) and read-only memory (ROM). The storage medium can be used to store instructions, programs, codes, code sets or instructions.

[0050] The display screen is used to display the user interface of each application.

[0051] All subscripts in the formula of the application are only used to distinguish parameters and have no actual meaning.

[0052] In addition, those skilled in the art can understand that the structure of the terminal described above does not constitute a limitation on the terminal, and the terminal can include more or fewer components, or combine certain components, or different component arrangements. For example, the terminal also includes radio frequency circuitry, input units, sensors, audio circuitry, power supplies, and other components, which are not described here.

[0053] Embodiment 1

[0054] As shown in Figure 1 , the present application proposes a UAV rescue full coverage search and rescue method, which is divided into six steps:

[0055] First, the search and rescue boundary is offset inward by a distance, which is to prevent the UAV from encountering danger. As shown in Figure 2 (a) (c), the dotted line is the boundary of the search and rescue area, and the multi-connected area enclosed by it is recorded as the inside of the search and rescue area. The search and rescue area boundary is offset inward by a distance to obtain the search and rescue area boundary offset line.

[0056] Second, determine whether the area center enclosed by the search and rescue area boundary offset line has a hole. When there is a hole, use ring-shaped slit mapping to map the area containing the boundary to a ring containing a slit through conformal slit mapping, as shown in Figure 2 (a) (b), the boundary of the area is mapped to the inner and outer boundaries of the ring and the internal circular arc-shaped slit. When there is no hole, use disc-shaped slit mapping to map the area containing the boundary to a disc containing a slit through slit mapping, as shown in Figure 2 (c) (d), the boundary of the area is mapped to the outer boundary of the disc and the internal circular arc-shaped slit.

[0057] Third, the cluster of concentric circle lines on the ring or disc image domain is mapped back to the original image after inverse mapping of conformal slit mapping, obtaining the isoparametric lines on the original image. Adjust the radius of the cluster of concentric circle lines so that the maximum inscribed circle radius of the area between adjacent isoparametric lines is a set value, as shown in Figure 3 .

[0058] Fourth, on the image domain, the concentric circles are offset to adjacent concentric circles to obtain non-equidistant spiral lines. Adjust the offset speed to avoid intersection between the non-equidistant spiral lines and the slits in the image domain, obtaining non-equidistant spiral lines in the image domain that do not intersect with the slits, as shown in Figure 4 (b) (d).

[0059] Fifth, the non-equidistant spiral lines are mapped back to the original image after inverse mapping of conformal slit mapping, obtaining spiral trajectories on the original image, as shown in Figure 4 (a) (c).

[0060] Sixth, search along the boundary offset line, and check the dangerous areas that cannot be searched by a small number of spiral trajectories. Since the spiral trajectories generated by the above method have a close-to-edge property, the search along the boundary offset line can be performed byFigure 5 The method and the search along the spiral trajectory are combined, the combined method is to find the position where the boundary offset line and the spiral trajectory are close and the tangential vector direction is approximately on the same line, the two trajectories are combined into one through the smooth curve intersection bridge, which avoids the sharp turning of the path after combination, but also makes the trajectory produce an intersection point. The search along the boundary offset line can also be performed alone.

[0061] Specifically, the boundary of the search area is determined by the set boundary function, including:

[0062]

[0063] Where B is the boundary function, M is the number of boundaries, L is the length of the trajectory, a is the transition adjustment factor, s is the arc length on the trajectory, μ′ i is the position where the ith transition occurs.

[0064] Specifically, the obstacle avoidance is performed by setting the obstacle avoidance function, including:

[0065]

[0066] Where O is the obstacle avoidance function, N is the number of obstacles, L is the length of the trajectory, s is the arc length on the trajectory, μ i is the mean of the ith Gaussian function, σ i is the ith standard deviation.

[0067] Specifically, the search trajectory is made smoother by setting the smoothness function, including:

[0068]

[0069] Where S' is the smoothness function, k(s) is the curvature of the point on the trajectory with arc length s, v(s) is the speed of the point on the trajectory with arc length s, is the turning rate of the point on the trajectory with arc length s, is the acceleration of the point on the trajectory with arc length s, L is the length of the trajectory, β is the turning rate weight, γ is the speed weight, δ is the acceleration weight.

[0070] Specifically, the search trajectory is made smoother by setting the smoothness function, including:

[0071]

[0072] Where D is the distance function, N' is the number of points on the trajectory with arc length s, d i is the distance between the ith point and the adjacent point on the trajectory with arc length s, is the average distance between the points on the trajectory with arc length s.

[0073] Embodiment 2

[0074] As Figure 6 shown, the application also proposes a UAV rescue full-coverage search and rescue system, comprising:

[0075] The slit acquisition module is used to offset the search and rescue boundary inward by a distance to obtain a search and rescue area boundary offset line, and to judge whether the center of the area surrounded by the search and rescue area boundary offset line has a hole. When there is a hole, the area is mapped onto a slit-containing annulus through conformal slit mapping by using annular slit mapping, and the boundary of the area is mapped into the inner and outer side boundaries of the annulus and the internal circular arc-shaped slit. When there is no hole, the area is mapped onto a slit-containing disc through slit mapping by using disc-shaped slit mapping, and the boundary of the area is mapped into the outer side boundary of the disc and the internal circular arc-shaped slit.

[0076] The unequal division spiral line acquisition module is used to map the concentric circular line cluster on the annulus or disc image domain back to the original image domain after inverse mapping of conformal slit mapping to obtain the isoparametric line on the original image, and to adjust the radius of the concentric circular line cluster so that the maximum inscribed circle radius between adjacent isoparametric lines is a set value. On the annulus or disc image domain, the concentric circles are gradually offset to adjacent concentric circles to obtain unequal distance spiral lines, and the offset speed is adjusted to avoid intersection of the unequal distance spiral lines with the slits in the image domain, to obtain unequal division spiral lines in the annulus or disc image domain that do not intersect with the slits.

[0077] The dangerous area investigation module is used to obtain the spiral trajectory on the original image after inverse mapping of conformal slit mapping of the unequal division spiral lines, to search along the search and rescue area boundary offset line, and to investigate the dangerous area that cannot be searched by the spiral trajectory.

[0078] Specifically, the boundary function is set to judge the boundary of the search and rescue area, including:

[0079]

[0080] Wherein, B is the boundary function, M is the number of boundaries, L is the length of the trajectory, a is the transition adjustment factor, s is the arc length on the trajectory, μ' i is the position where the ith transition occurs.

[0081] Specifically, the obstacle avoidance function is set to avoid obstacles, including:

[0082]

[0083] Wherein, O is the obstacle avoidance function, N is the number of obstacles, L is the length of the trajectory, s is the arc length on the trajectory, μ i is the mean of the ith Gaussian function, σ i is the ith standard deviation.

[0084] Specifically, the smoothness function is set to make the search and rescue trajectory smoother, including:

[0085]

[0086] wherein S' is the smoothness function, k(s) is the curvature of the point on the trajectory with arc length s, v(s) is the speed of the point on the trajectory with arc length s, is the turning rate of the point on the trajectory with arc length s, is the acceleration of the point on the trajectory with arc length s, L is the length of the trajectory, β is the turning rate weight, γ is the speed weight, and δ is the acceleration weight.

[0087] Specifically, the spacing function is set to avoid excessive twists of the search and rescue trajectory, including:

[0088]

[0089] wherein D is the spacing function, N' is the number of points on the trajectory with arc length s, d i is the distance between the i-th point on the trajectory with arc length s and the adjacent point, is the average distance between the points on the trajectory with arc length s.

[0090] Embodiment 3

[0091] The embodiment of the present application also proposes a storage medium, which stores a plurality of instructions for implementing the search and rescue method for full coverage of unmanned aerial vehicle rescue.

[0092] Optionally, in the present embodiment, the above-mentioned storage medium can be located in any one of the computer terminals in the computer terminal group in the computer network, or in any one of the mobile terminals in the mobile terminal group.

[0093] Optionally, in the present embodiment, the storage medium is set to store program codes for executing the method steps of embodiment 1.

[0094] Embodiment 4

[0095] The embodiment of the present application also proposes an electronic device, which includes a processor and a storage medium connected to the processor, and the storage medium stores a plurality of instructions, which can be loaded and executed by the processor, so that the processor can execute a search and rescue method for full coverage of unmanned aerial vehicle rescue.

[0096] Specifically, the electronic device of the present embodiment can be a computer terminal, which can include one or more processors and a storage medium.

[0097] The storage medium can be used to store software programs and modules, such as the unmanned aerial vehicle rescue full coverage search and rescue method in the embodiment of the application, corresponding program instructions / modules, and the processor executes various function applications and data processing by running the software programs and modules stored in the storage medium, that is, the above-mentioned unmanned aerial vehicle rescue full coverage search and rescue method is realized. The storage medium can include a high-speed random storage medium, and can also include a non-volatile storage medium, such as one or more magnetic storage systems, flash memories, or other non-volatile solid-state storage media. In some examples, the storage medium can further include storage media remotely arranged with respect to the processor, and the remote storage media can be connected to the terminal through a network. Examples of the above-mentioned network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof.

[0098] The processor can call the information and application programs stored in the storage medium through the transmission system to execute the method steps of the embodiment 1.

[0099] The above-mentioned embodiment numbers of the application are only for description, and do not represent the advantages and disadvantages of the embodiments.

[0100] In the above-mentioned embodiments of the application, the description of each embodiment has its own emphasis, and the parts not described in detail in a certain embodiment can be referred to the related description of other embodiments.

[0101] In the several embodiments of the application provided, it should be understood that the disclosed technology can be implemented in other ways. Of course, the above-mentioned system embodiments are only illustrative, for example, the division of the units is only a logical function division, and there can be another division manner in actual implementation, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some interfaces, units or modules, and can be electrical or other forms.

[0102] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, that is, they can be located in one place, or can be distributed on a plurality of network units. According to actual needs, part or all of the units can be selected to achieve the purpose of the embodiment.

[0103] In addition, each functional unit in each embodiment of the application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0104] The integrated unit, if implemented in the form of a software function unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or say the part that contributes to the prior art or all or part of the technical solutions can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to make a computer device (which can be a personal computer, a server or a network device, etc.) execute all or part of the steps of the method described in various embodiments of the present application. The foregoing storage medium includes: a U disk, a read-only storage medium (ROM, Read-Only Memory), a random access storage medium (RAM, Random Access Memory), a mobile hard disk, a magnetic disk or an optical disk, and various media that can store program codes.

[0105] Obviously, the above embodiments are only examples for clearly illustrating, and not limiting the embodiments. For those skilled in the art, on the basis of the above description, other different forms of changes or variations can also be made. Here, it is not necessary and also impossible to enumerate all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A UAV rescue full coverage search and rescue method, characterized in that, The method comprises the following steps: The search and rescue boundary is offset inward by a distance to obtain a search and rescue area boundary offset line, and it is judged whether the center of the area surrounded by the search and rescue area boundary offset line has a hole; when there is a hole, ring-shaped slit mapping is adopted to map the area to a slit-containing annulus through conformal slit mapping, and the boundary of the area is mapped into the inner and outer side boundaries of the annulus and the internal circular-arc-shaped slit; when there is no hole, disc-shaped slit mapping is adopted to map the area to a slit-containing disc through slit mapping, and the boundary of the area is mapped into the outer side boundary of the disc and the internal circular-arc-shaped slit; After the inverse mapping of the conformal slit mapping of the concentric circle line cluster on the annulus or disc image domain is mapped back to the original image domain, isometric lines on the original image are obtained, the radii of the concentric circle line cluster are adjusted so that the maximum inscribed circle radius between adjacent isometric lines is a set value; on the annulus or disc image domain, the concentric circles are gradually offset to adjacent concentric circles to obtain non-equidistant spiral lines, and the offset speed is adjusted to avoid the intersection of the non-equidistant spiral lines with the slits in the image domain, so that non-equidistant spiral lines in the annulus or disc image domain are obtained which do not intersect with the slits. After the inverse mapping of the conformal slit mapping of the non-equidistant spiral lines is mapped back to the original image domain, spiral trajectories on the original image are obtained, and the dangerous area which cannot be searched and rescued by the spiral trajectories is searched and rescued along the search and rescue area boundary offset line.

2. The unmanned aerial vehicle rescue full coverage search and rescue method of claim 1, wherein, The boundary function is set to judge the boundary of the search and rescue area, which comprises: where B is the boundary function, M is the number of boundaries, L is the length of the trajectory, a is a transition adjustment factor, s is the arc length along the trajectory, μ′ i is the location where the ith transition occurs.

3. The unmanned aerial vehicle rescue full coverage search and rescue method of claim 1, wherein, The obstacle avoidance function is set to avoid obstacles, which comprises: where O is an obstacle avoidance function, N is the number of obstacles, L is the length of the trajectory, s is the arc length along the trajectory, μ i is the mean of the ith Gaussian function, σ i is the ith standard deviation.

4. The unmanned aerial vehicle rescue full coverage search and rescue method of claim 1, wherein, The smoothness function is set to make the search and rescue trajectory smoother, which comprises: where S' is a smoothness function, k(s) is the curvature of a point on the trajectory at arc length s, v(s) is the speed of a point on the trajectory at arc length s, is the turning rate of a point on the trajectory at arc length s, is the acceleration of a point on the trajectory at arc length s, L is the length of the trajectory, β is a turning rate weight, γ is a speed weight, and δ is an acceleration weight.

5. The unmanned aerial vehicle rescue full coverage search and rescue method of claim 1, wherein, The spacing function is set to avoid excessive tortuosity of the search and rescue trajectory, which comprises: where D is a distance function, N' is the number of points on the trajectory with arc length s, d i is the distance between the i-th point and the adjacent point on the trajectory with arc length s, is the average distance between points on the trajectory with arc length s.

6. An unmanned aerial vehicle rescue all-coverage search and rescue system characterized by, The method comprises the following steps: The search and rescue boundary is offset inward by a distance to obtain a search and rescue area boundary offset line, and it is judged whether the center of the area surrounded by the search and rescue area boundary offset line has a hole; when there is a hole, ring-shaped slit mapping is adopted to map the area to a slit-containing annulus through conformal slit mapping, and the boundary of the area is mapped into the inner and outer side boundaries of the annulus and the internal circular-arc-shaped slit; when there is no hole, disc-shaped slit mapping is adopted to map the area to a slit-containing disc through slit mapping, and the boundary of the area is mapped into the outer side boundary of the disc and the internal circular-arc-shaped slit; The non-equidistant spiral line module is used to map the concentric circle line cluster on the annulus or disc image domain through the inverse mapping of the conformal slit mapping, so as to obtain isometric lines on the original image; the radii of the concentric circle line cluster are adjusted so that the maximum inscribed circle radius between adjacent isometric lines is a set value; on the annulus or disc image domain, the concentric circles are gradually offset to adjacent concentric circles to obtain non-equidistant spiral lines, and the offset speed is adjusted to avoid the intersection of the non-equidistant spiral lines with the slits in the image domain, so that non-equidistant spiral lines in the annulus or disc image domain are obtained which do not intersect with the slits. The dangerous area searching module is used to map the non-equidistant spiral lines through the inverse mapping of the conformal slit mapping, so as to obtain spiral trajectories on the original image; the dangerous area which cannot be searched and rescued by the spiral trajectories is searched and rescued along the search and rescue area boundary offset line.

7. A UAV rescue all-coverage search and rescue system as claimed in claim 6, wherein, The boundary function is set to judge the boundary of the search and rescue area, which comprises: where B is the boundary function, M is the number of boundaries, L is the length of the trajectory, a is a transition adjustment factor, s is the arc length along the trajectory, μ′ i is the location where the ith transition occurs.

8. The UAV rescue all-coverage search and rescue system of claim 6, wherein, The obstacle avoidance function is set to avoid obstacles, which comprises: where O is an obstacle avoidance function, N is the number of obstacles, L is the length of the trajectory, s is the arc length along the trajectory, μ i is the mean of the ith Gaussian function, σ i is the ith standard deviation.

9. The UAV rescue all-coverage search and rescue system of claim 6, wherein, The smoothness function is set to make the search and rescue trajectory smoother, which comprises: where S' is a smoothness function, k(s) is the curvature of a point on the trajectory at arc length s, v(s) is the speed of a point on the trajectory at arc length s, is the turning rate of a point on the trajectory at arc length s, is the acceleration of a point on the trajectory at arc length s, L is the length of the trajectory, β is a turning rate weight, γ is a speed weight, and δ is an acceleration weight.

10. The UAV rescue all-coverage search and rescue system of claim 6, wherein, The spacing function is set to avoid excessive tortuosity of the search and rescue trajectory, which comprises: where D is a distance function, N' is the number of points on the trajectory with arc length s, d i is the distance between the i-th point and the adjacent point on the trajectory with arc length s, is the average distance between points on the trajectory with arc length s.

Images