Landing guidance method and system for vehicle-mounted fire extinguishing and rescue unmanned aerial vehicle landing support platform

Abstract

The application discloses a landing guiding method and system for a vehicle-mounted fire extinguishing and rescue unmanned aerial vehicle (UAV) take-off and landing guarantee platform, and belongs to the technical field of UAVs. Through application of coding beacons and positioning receivers with specific shapes, the distance of the UAV relative to each coding beacon and the direction of the UAV can be determined through twice differential operation on the received guiding signals, and then landing guiding instructions for adjusting the position and direction of the UAV are generated, so that the flight control system of the UAV can adjust the direction and position of the UAV after executing the landing guiding instructions, so that the direction of the UAV and the distance between the UAV and each coding beacon meet the landing requirements, and thus precise landing guiding is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of unmanned aerial vehicles, in particular to a landing guiding method and system of a vehicle-mounted fire-fighting rescue unmanned aerial vehicle take-off and landing guarantee platform. BACKGROUND

[0002] With the rapid development of unmanned aerial vehicle technology, unmanned aerial vehicles carrying fire hoses are also applied in the field of fire-fighting rescue to carry out high-altitude fire-fighting operations. Such unmanned aerial vehicles are usually configured with a vehicle carrying an unmanned aerial vehicle guarantee platform. Compared with the traditional vehicle-mounted unmanned aerial vehicle guarantee platform, the vehicle-mounted guarantee platform of the fire-fighting rescue unmanned aerial vehicle is additionally configured with a water supply pipe.

[0003] Similar to the ordinary vehicle-mounted guarantee platform, the vehicle-mounted fire-fighting rescue unmanned aerial vehicle take-off and landing guarantee platform also needs to provide accurate landing guidance for the unmanned aerial vehicle to ensure that the unmanned aerial vehicle can land at the designated position of the guarantee platform in the designated direction. However, the existing landing guidance method is mainly based on manual operation, which requires high experience of the operator and has a large human error. SUMMARY

[0004] In view of the problem that the vehicle-mounted fire-fighting rescue unmanned aerial vehicle take-off and landing guarantee platform relies on manual guidance of the unmanned aerial vehicle landing in the prior art, the purpose of the present application is to provide a landing guiding method and system of a vehicle-mounted fire-fighting rescue unmanned aerial vehicle take-off and landing guarantee platform, so as to at least partially solve the above problems.

[0005] To achieve the above-mentioned purpose, the technical solution of the present application is as follows:

[0006] In a first aspect, the present application provides a landing guiding method of a vehicle-mounted fire-fighting rescue unmanned aerial vehicle take-off and landing guarantee platform. The method is applied to the vehicle-mounted fire-fighting rescue unmanned aerial vehicle take-off and landing guarantee platform. At least three coded beacons for emitting guiding signals and having unique codes are arranged on the take-off and landing guarantee platform. A positioning receiver is installed on the unmanned aerial vehicle. The positioning receiver includes a receiver body in the shape of an inverted truncated pyramid and at least one signal receiving element for receiving guiding signals arranged on each platform surface of the receiver body, respectively.

[0007] The method is applied to the landing stage guidance of the unmanned aerial vehicle. The method includes the following steps:

[0008] S1. Obtain the guiding signals received by each signal receiving element on each platform surface of the positioning receiver, and associate the guiding signals with their corresponding signal receiving elements;

[0009] S2. Decode the received guiding signals to determine the correspondence between the guiding signals and the coded beacons;

[0010] S3. respectively, the first difference operation and the second difference operation are performed on the guide signals to which the coded beacons belong, and the position and direction of the unmanned aerial vehicle are determined based on the difference operation results;

[0011] S4. the landing guide instruction is generated according to the position and direction of the unmanned aerial vehicle, and the flight control system of the unmanned aerial vehicle adjusts the direction and position of the unmanned aerial vehicle after executing the landing guide instruction, so that the position and direction of the unmanned aerial vehicle meet the preset threshold.

[0012] In some preferred embodiments, the coded beacon is a visible light coded beacon, adopts pulse width modulation coding, and represents binary information with uniqueness by emitting guide signals with different pulse width combinations.

[0013] In some preferred embodiments, the receiver body is in the shape of an inverted quadrangular pyramid table, M×N photosensitive elements are arranged in a matrix on each table surface, there are four coded beacons, and the distribution shape of the four coded beacons is the same as the shape of the bottom surface of the receiver body.

[0014] In some preferred embodiments, in step S1, the step of associating the guide signals with the corresponding signal receiving elements includes:

[0015] In the center of gravity coordinate system of the unmanned aerial vehicle, the position coordinates of each signal receiving element are established, and the position coordinates of the guide signals and the corresponding signal receiving elements in the center of gravity coordinate system of the unmanned aerial vehicle are associated.

[0016] In some preferred embodiments, in step S3, the first difference operation object is the guide signal received by each signal receiving element in any table surface of the positioning receiver from the same coded beacon, so as to determine the locally strongest guide signal received by any table surface from the same coded beacon; the second difference operation object is the locally strongest guide signal received by each table surface of the positioning receiver from the same coded beacon, so as to determine the globally strongest guide signal received by the positioning receiver from the same coded beacon, and the relationship between the locally strongest guide signals received by each table surface from the same coded beacon.

[0017] In some preferred embodiments, in step S3, the step of determining the position of the unmanned aerial vehicle based on the difference operation results includes:

[0018] The globally strongest guide signal received by the positioning receiver from the same coded beacon and the associated signal receiving element are combined with the RSSI operation model to determine the distance between each coded beacon and the signal receiving element corresponding to the globally strongest guide signal of the coded beacon;

[0019] A vehicle-mounted coordinate system is constructed, and the position coordinates of each coded beacon in the vehicle-mounted coordinate system are determined according to the installation positions of the coded beacons on the vehicle.

[0020] According to the distance between each coded beacon and the signal receiving element corresponding to the global strongest guiding signal of the coded beacon, and in combination with the position coordinates of the signal receiving element corresponding to the global strongest guiding signal of each coded beacon in the UAV gravity center coordinate system, the position coordinates of the UAV gravity center in the vehicle coordinate system are calculated and obtained, and the position of the UAV is determined.

[0021] In some preferred embodiments, in step S3, the step of determining the direction of the UAV based on the difference operation result comprises:

[0022] According to the position coordinates of the UAV gravity center in the vehicle coordinate system and the position coordinates of each coded beacon in the vehicle coordinate system, the distance between each coded beacon and the UAV is determined.

[0023] According to the distance between each coded beacon and the UAV, in combination with the relationship between the locally strongest guiding signals from the same coded beacon received by each platform, the direction of the UAV is determined, comprising:

[0024] The direction of the UAV is determined by querying the pre-calibrated mapping table, wherein the pre-calibrated mapping table records the relationship between the locally strongest guiding signals from the same coded beacon received by each platform at different distances and different orientations, and when the distance and the relationship between the locally strongest guiding signals from the same coded beacon received by each platform are determined, the direction of the UAV can be obtained by querying the pre-calibrated mapping table, i.e., the direction of the UAV.

[0025] In a second aspect, the application also provides a landing guiding system of a vehicle-mounted fire extinguishing and rescue UAV take-off and landing support platform, which is applied to a vehicle-mounted fire extinguishing and rescue UAV take-off and landing support platform, at least three coded beacons for emitting guiding signals and having uniqueness are arranged on the take-off and landing support platform, and a positioning receiver is installed on the UAV, wherein the positioning receiver comprises a receiver body in the shape of an inverted truncated pyramid and at least one signal receiving element for receiving guiding signals arranged on each platform of the receiver body, respectively.

[0026] The system is applied to the landing stage guiding of the UAV, and the system comprises:

[0027] A signal acquisition module is configured to acquire the guiding signals received by each signal receiving element on each platform of the positioning receiver, and associate the guiding signals with the corresponding signal receiving elements;

[0028] A signal decoding module is configured to decode the received guiding signals and determine the corresponding relationship between the guiding signals and each coded beacon.

[0029] a signal operation module, configured to perform first-order differential operation and second-order differential operation on the guidance signals to which the coded beacons belong respectively, and determine the position and direction of the UAV based on the results of the differential operation;

[0030] and an instruction generation module, configured to generate a landing guidance instruction according to the position and direction of the UAV, the flight control system of the UAV executing the landing guidance instruction being able to adjust the direction and position of the UAV so as to make the direction and position of the UAV satisfy a preset threshold.

[0031] In some preferred embodiments, the first-order differential operation object of the signal operation module is the guidance signals received by each signal receiving element in any platform of the positioning receiver from the same coded beacon, so as to determine the locally strongest guidance signal received by any platform from the same coded beacon; the second-order differential operation object of the signal operation module is the locally strongest guidance signal received by each platform of the positioning receiver from the same coded beacon, so as to determine the globally strongest guidance signal received by the positioning receiver from the same coded beacon, and the relationship between the locally strongest guidance signals received by each platform from the same coded beacon.

[0032] In some preferred embodiments, the signal operation module comprises a position determination unit and a direction determination unit.

[0033] The position determination unit is configured to determine the distance between each coded beacon and the signal receiving element corresponding to the globally strongest guidance signal of the coded beacon by the globally strongest guidance signal received by the positioning receiver from the same coded beacon and the associated signal receiving element, in combination with an RSSI operation model; construct a vehicle coordinate system, and determine the position coordinates of each coded beacon in the vehicle coordinate system according to the installation position of each coded beacon on the vehicle; and calculate the position coordinates of the center of gravity of the UAV in the vehicle coordinate system according to the distance between each coded beacon and the signal receiving element corresponding to the globally strongest guidance signal of the coded beacon, in combination with the position coordinates of the signal receiving element corresponding to the globally strongest guidance signal of each coded beacon in the UAV gravity center coordinate system, so as to determine the position of the UAV.

[0034] The direction determining unit is configured to determine the distance between each coded beacon and the UAV according to the position coordinates of the center of gravity of the UAV in the vehicle coordinate system and the position coordinates of each coded beacon in the vehicle coordinate system, and determine the direction of the UAV according to the distance between each coded beacon and the UAV, in combination with the relationship between the locally strongest guide signals from the same coded beacon received by each platform, including: determining the direction of the UAV by querying a pre-calibrated mapping table, wherein the pre-calibrated mapping table records the relationship between the locally strongest guide signals from the same coded beacon received by each platform under different distances and different directions, and when the distance and the relationship between the locally strongest guide signals from the same coded beacon received by each platform are determined, the direction of the UAV can be obtained by querying the pre-calibrated mapping table, i.e., the direction of the UAV.

[0035] By using the above technical solutions, the application has the following beneficial effects: by using the coded beacon and the positioning receiver with a specific shape, the distance between the UAV and each coded beacon and the direction of the UAV can be determined by performing twice differential operation on the received guide signals, and then the landing guide instruction for adjusting the position and direction of the UAV is generated, so that the flight control system of the UAV can adjust the direction and position of the UAV after executing the landing guide instruction, so that the direction of the UAV and the distance between the UAV and each coded beacon meet the landing requirements, thereby realizing precise landing guidance. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 FIG. 1 is a flowchart of a landing guidance method of a vehicle-mounted fire-fighting and rescue UAV take-off and landing support platform according to an embodiment of the application;

[0037] Figure 2 FIG. 2 is a structural diagram of a landing guidance system of a vehicle-mounted fire-fighting and rescue UAV take-off and landing support platform according to an embodiment of the application. DETAILED DESCRIPTION

[0038] The specific embodiments of the application will be further described below with reference to the accompanying drawings. It should be noted that the description of the embodiments is used to help understand the application, but does not constitute a limitation of the application. In addition, the technical features involved in each embodiment of the application described below can be combined with each other as long as there is no conflict.

[0039] Embodiment 1:

[0040] Reference is made to Figure 1 FIG. 1 is a flowchart of a landing guidance method of a vehicle-mounted fire-fighting and rescue UAV take-off and landing support platform according to an embodiment of the application, Figure 1The execution subject of the method can be a software and / or a hardware device. The execution subject of the present application can include, but is not limited to, at least one of the following: a user equipment, a network equipment, and the like. Among them, the user equipment can include, but is not limited to, a computer, a smart phone, a personal digital assistant (PDA), and the above-mentioned electronic devices, and the like. The network equipment can include, but is not limited to, a single network server, a server group composed of multiple network servers, or a cloud composed of a large number of computers or network servers based on cloud computing. The cloud computing is a kind of distributed computing, which is a super virtual computer composed of a group of loosely coupled computers. The present embodiment does not make any limitation.

[0041] A landing guidance method of a vehicle-mounted fire extinguishing and rescue unmanned aerial vehicle take-off and landing support platform, the method is applied to the vehicle-mounted fire extinguishing and rescue unmanned aerial vehicle take-off and landing support platform.

[0042] Among them, at least three encoding beacons for emitting guidance signals and having uniqueness are arranged on the take-off and landing support platform, and a positioning receiver is installed on the unmanned aerial vehicle, the positioning receiver includes a receiver body in the shape of an inverted truncated pyramid and at least one signal receiving element for receiving the guidance signals arranged on each platform surface of the receiver body.

[0043] In particular, in the present embodiment, the encoding beacon is configured as a visible light encoding beacon, and the signal is broadcasted and emitted upward in the airspace through high-frequency (above 50 Hz) flashing. It adopts pulse width modulation coding, and represents binary information with uniqueness by emitting guidance signals with different pulse width combinations. In the case that the binary information emitted is unique, the positioning receiver can distinguish the source of the received guidance signals. For example, the visible light encoding beacon includes a control circuit, an encoding modulation circuit, a signal amplification and LED driving circuit, etc. The emitted binary information is usually composed of a start field (2 bytes, such as FF), an information field (1 byte), a vehicle encoding bit (4 bits), a beacon serial number bit (2 bits), a check bit (2 bits), an end field (1 byte), etc.

[0044] In the present embodiment, the receiver body of the positioning receiver is further configured in the shape of an inverted quadrangular pyramid, which has four side inclined surfaces and one flat bottom surface, a total of five platform surfaces, and M×N photosensitive elements are arranged in a matrix on each platform surface, for example, 2×3. Of course, M can also be the same as N, for example, 3×3. Correspondingly, the present embodiment configures four encoding beacons, and the four encoding beacons are distributed in a rectangular shape at the top of the four corners of the vehicle, for example, the take-off and landing support platform is in the shape of a container, and the four encoding beacons are fixedly installed at the top of the four corners of the container. In fact, only three encoding beacons arranged non-collinearly are needed.

[0045] The method provided by the present embodiment is specifically applied to the landing stage guidance of the unmanned aerial vehicle, such asFigure 1 As shown, the method comprises four steps S1 to S4.

[0046] S1. Obtain the guiding signals received by each signal receiving element on each platform of the positioning receiver, and associate the guiding signals with their corresponding signal receiving elements.

[0047] S2. Decode the received guiding signals to determine the correspondence between the guiding signals and the coded beacons.

[0048] S3. Perform first-order difference operation and second-order difference operation on the guiding signals to which each coded beacon belongs, respectively, and determine the position and direction of the UAV based on the difference operation results.

[0049] S4. Generate a landing guidance instruction according to the position and direction of the UAV, and the flight control system of the UAV executes the landing guidance instruction to adjust the direction and position of the UAV so that the position and direction of the UAV meet the preset threshold.

[0050] Due to the shape of the positioning receiver in this embodiment, the guiding signals emitted by each visible light coded beacon are received by at least two signal receiving elements (i.e. light sensitive elements) on the platforms, so for a single signal receiving element (i.e. light sensitive element), it will receive guiding signals emitted by more than one visible light coded beacon. Therefore, in order to avoid confusion, in step S1, it is necessary to associate each guiding signal with its corresponding signal receiving element, and the specific steps include:

[0051] Under the UAV barycentric coordinate system, the position coordinates of each signal receiving element are established, and then each guiding signal is associated with the position coordinates of the corresponding signal receiving element under the UAV barycentric coordinate system.

[0052] After such association, for each guiding signal, it can be known which signal receiving element receives it.

[0053] However, at this time, it is still not possible to distinguish the sources of the guiding signals, so in step S2, it is necessary to decode all the guiding signals received by the positioning receiver to further determine the correspondence between each guiding signal and the coded beacon.

[0054] After the processing of steps S1 and S2, it can be known which signal receiving elements receive the guiding signals emitted by each coded beacon.

[0055] On this basis, the content of step S3 is executed, specifically including two levels of difference operation. Among them, the first difference operation object is the guide signal received by each signal receiving element in the arbitrary deck of the positioning receiver from the same coded beacon, so as to determine the locally strongest guide signal received by the arbitrary deck from the same coded beacon; wherein the second difference operation object is the locally strongest guide signal received by each deck of the positioning receiver from the same coded beacon, so as to determine the globally strongest guide signal received by the positioning receiver from the same coded beacon, and the relationship between the locally strongest guide signals received by each deck from the same coded beacon.

[0056] We take a single coded beacon (such as the coded beacon installed at the left front of the vehicle, hereinafter referred to as No. 1 beacon) as an example for illustration:

[0057] First, all the guide signals belonging to No. 1 beacon are screened out, and then it is clear that these guide signals are received by which signal receiving elements.

[0058] Then, the first difference operation object is the guide signal received by each signal receiving element in each deck of the positioning receiver from the same coded beacon, and through the first difference operation, the guide signal with the strongest signal strength received by each deck from No. 1 beacon can be determined, hereinafter referred to as the locally strongest guide signal.

[0059] Then, the second difference operation object is the locally strongest guide signal from No. 1 beacon on each deck of the positioning receiver, which can determine the guide signal with the strongest signal strength received by the positioning receiver from No. 1 beacon, hereinafter referred to as the globally strongest guide signal, and on the other hand, it can also determine the relationship between the locally strongest guide signals on each deck.

[0060] Similarly, for other coded beacons, the corresponding locally strongest guide signal, globally strongest guide signal and the relationship between the locally strongest guide signals on each deck can also be calculated and obtained.

[0061] In step S3, the step of determining the position of the unmanned aerial vehicle based on the difference operation result includes:

[0062] According to the globally strongest guide signal received by the positioning receiver from No. 1 beacon determined in step S3, and combined with the RSSI operation model, the distance between No. 1 beacon and the signal receiving element associated with the globally strongest guide signal can be calculated, and similarly the distances between the other three signals and their corresponding signal receiving elements can be calculated. At this point, four distance parameters can be obtained, which all represent the distance between the beacon and the signal receiving element.

[0063] In the vehicle coordinate system, the installation positions of the coded beacons on the vehicle are fixed and known, so the position coordinates of the coded beacons in the vehicle coordinate system can be known.

[0064] In the UAV center of gravity coordinate system, the inverted quadrangular pyramid platform type receiver body is of a known shape and size, and the distribution positions of each signal receiving element thereon are also fixed and known, so the position coordinates of the signal receiving element corresponding to the globally strongest guiding signal of the four coded beacons in the UAV center of gravity coordinate system can be known.

[0065] Combining the above three, the unique position of the UAV center of gravity in the vehicle coordinate system, i.e., the position of the UAV, can be determined.

[0066] In step S3, the step of determining the direction of the UAV based on the difference operation result includes:

[0067] In the case that the position of the UAV has been determined, the distances between the coded beacons and the center of gravity of the UAV can be determined.

[0068] It is easy to understand that in the accurate landing attitude of the UAV, it has a specific orientation, for example, a certain specific component on the UAV is oriented to the front of the vehicle, etc., and the angular relationship between the No. 1 beacon and each platform of the positioning receiver is basically determined, at this time, the guiding signal emitted by the No. 1 beacon will only be received by a few specific platforms (the orientation of the UAV can be roughly ensured by rotating the UAV, but it is not accurate enough and needs to be finely adjusted), at this time, when the distance between the center of gravity of the UAV and the No. 1 beacon is determined, the distance between the No. 1 beacon and each platform of the positioning receiver is also determined, and the strength relationship of the guiding signals received by each platform from the No. 1 beacon is also basically determined. If the orientation of the UAV is not accurate enough, it will cause a certain platform to be farther away from the No. 1 beacon and a certain platform to be closer to the No. 1 beacon, according to the difference and proportional relationship between the signal strengths of the locally strongest guiding signals on each platform, the deviation of the orientation of the UAV can be known, and the corresponding adjustment is needed.

[0069] On this basis, the current direction of the unmanned aerial vehicle can be determined by querying the pre-calibrated mapping table according to the relationship between the local strongest guide signals received by each platform from the No. 1 beacon obtained by the first difference operation. The pre-calibrated mapping table records the relationship between the local strongest guide signals received by each platform from the No. 1 beacon under different distances (herein, the distance between the No. 1 beacon and the center of gravity of the unmanned aerial vehicle), different orientations (the unmanned aerial vehicle has a specific orientation under the accurate landing posture, such as a specific component of the unmanned aerial vehicle facing the front of the vehicle, etc.), and actual measurement. Thus, when the distance and the relationship between the local strongest guide signals received by each platform from the No. 1 beacon are determined, the orientation of the unmanned aerial vehicle, i.e., the direction of the unmanned aerial vehicle, can be obtained by querying the pre-calibrated mapping table. Of course, the orientation of the unmanned aerial vehicle can be more accurately known (e.g., by taking an average value) by performing the above steps on multiple coded beacons, thereby reducing errors.

[0070] When the position and the orientation of the unmanned aerial vehicle are known, a landing guide instruction is generated. After the flight control system of the unmanned aerial vehicle executes the landing guide instruction, the direction and the position of the unmanned aerial vehicle can be adjusted to make the position and the direction of the unmanned aerial vehicle satisfy a preset threshold, so that the unmanned aerial vehicle is in an accurate position and orientation.

[0071] Embodiment 2:

[0072] A landing guide system of a vehicle-mounted fire-fighting and rescue unmanned aerial vehicle take-off and landing support platform, which is applied to a vehicle-mounted fire-fighting and rescue unmanned aerial vehicle take-off and landing support platform. At least three coded beacons for emitting guide signals and having unique codes are arranged on the take-off and landing support platform. A positioning receiver is installed on the unmanned aerial vehicle, which includes a receiver body in the shape of an inverted truncated pyramid and at least one signal receiving element for receiving guide signals arranged on each platform of the receiver body.

[0073] In this embodiment, the coded beacon is configured as a visible light coded beacon, which broadcasts and emits signals to the upper space through high-frequency (more than 50 Hz) flashing. The coded beacon adopts pulse width modulation coding, and emits guide signals with different pulse width combinations to represent unique binary information. In the case that the emitted binary information is unique, the positioning receiver can distinguish the source of the received guide signals. For example, the visible light coded beacon includes a control circuit, a coding modulation circuit, a signal amplification and LED driving circuit, etc. The emitted binary information is usually composed of a start field (2 bytes, such as FF), an information field (1 byte), a vehicle code bit (4 bits), a beacon serial number bit (2 bits), a check bit (2 bits), an end field (1 byte), etc.

[0074] In the embodiment, the receiver body of the positioning receiver is further configured in an inverted quadrangular-pyramidal frustum type, which has four side inclined surfaces and one flat bottom surface, a total of five surfaces, and each surface is arranged with MxN photosensitive elements in a matrix, for example, 2x3, and of course M can also be the same as N, for example, 3x3. Correspondingly, the embodiment is configured with four encoding beacons, and the four encoding beacons are distributed in a rectangular manner at the top of the four corners of the vehicle carrier, for example, the landing support platform is in a container type, and the four encoding beacons are fixedly installed at the top of the four corners of the container.

[0075] As shown in Figure 2 The landing guidance system of the vehicle-mounted fire extinguishing and rescue unmanned aerial vehicle landing support platform provided by the embodiment includes a signal acquisition module, a signal decoding module, a signal operation module, and an instruction generation module.

[0076] The signal acquisition module is configured to acquire the guidance signals received by each signal receiving element on each surface of the positioning receiver, and associate the guidance signals with their corresponding signal receiving elements.

[0077] The signal decoding module is configured to decode the received guidance signals and determine the correspondence between the guidance signals and the encoding beacons.

[0078] The signal operation module is configured to perform first difference operation and second difference operation on the guidance signals belonging to each encoding beacon respectively, and determine the position and direction of the unmanned aerial vehicle based on the difference operation results.

[0079] The instruction generation module is configured to generate a landing guidance instruction according to the position and direction of the unmanned aerial vehicle, and the flight control system of the unmanned aerial vehicle can adjust the direction and position of the unmanned aerial vehicle after executing the landing guidance instruction, so that the direction and position of the unmanned aerial vehicle meet the preset threshold.

[0080] The first difference operation object of the signal operation module is the guidance signals received by each signal receiving element in any surface of the positioning receiver from the same encoding beacon, so as to determine the locally strongest guidance signals received by any surface from the same encoding beacon; the second difference operation object of the signal operation module is the locally strongest guidance signals received by each surface of the positioning receiver from the same encoding beacon, so as to determine the globally strongest guidance signals received by the positioning receiver from the same encoding beacon, and the relationship between the locally strongest guidance signals received by each surface from the same encoding beacon.

[0081] The signal operation module specifically includes a position determination unit and a direction determination unit.

[0082] The position determining unit is configured to determine the position of the UAV, and comprises the following steps: determining the distance between each coded beacon and the signal receiving element corresponding to the global strongest guiding signal of the coded beacon by combining the RSSI operation model, receiving the global strongest guiding signal from the same coded beacon by the positioning receiver and the associated signal receiving element; constructing a vehicle coordinate system, determining the position coordinates of each coded beacon in the vehicle coordinate system according to the installation position of each coded beacon on the vehicle; and calculating the position coordinates of the center of gravity of the UAV in the vehicle coordinate system according to the distance between each coded beacon and the signal receiving element corresponding to the global strongest guiding signal of the coded beacon, and the position coordinates of the signal receiving element corresponding to the global strongest guiding signal of each coded beacon in the UAV gravity coordinate system, and then determining the position of the UAV.

[0083] The direction determining unit is configured to determine the direction of the UAV, and comprises the following steps: determining the distance between each coded beacon and the UAV according to the position coordinates of the center of gravity of the UAV in the vehicle coordinate system and the position coordinates of each coded beacon in the vehicle coordinate system; and determining the direction of the UAV according to the distance between each coded beacon and the UAV, and the relationship between the local strongest guiding signals received by each platform from the same coded beacon, comprising: determining the direction of the UAV by querying the pre-calibrated mapping table, wherein the pre-calibrated mapping table records the relationship between the local strongest guiding signals received by each platform from the same coded beacon under different distances and different directions, and when the distance and the relationship between the local strongest guiding signals received by each platform from the same coded beacon are determined, the direction of the UAV can be obtained by querying the pre-calibrated mapping table, i.e. the direction of the UAV.

[0084] The embodiments of the present application are described in detail above in combination with the drawings, but the present application is not limited to the described embodiments. For those skilled in the art, various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and spirits of the present application, and still fall within the protection scope of the present application.

Claims

1. A landing guidance method for a vehicle-mounted firefighting and rescue drone take-off and landing support platform, characterized in that: The method is applied to a vehicle-mounted firefighting and rescue drone take-off and landing support platform. The take-off and landing support platform is equipped with at least three unique coded beacons for transmitting guidance signals. The drone is equipped with a positioning receiver, which includes a receiver body in the shape of an inverted truncated pyramid and at least one signal receiving element for receiving guidance signals, respectively arranged on each platform of the receiver body. The method is applied to the landing phase guidance of a UAV, and the method includes the following steps: S1. Obtain the guidance signal received by each signal receiving element on each platform of the positioning receiver, and associate the guidance signal with its corresponding signal receiving element; S2. Decode the received guidance signal to determine the correspondence between the guidance signal and each coded beacon; S3. Perform a first differential operation and a second differential operation on the guidance signal of each coded beacon, and determine the position and orientation of the UAV based on the differential operation results; S4. A landing guidance command is generated based on the drone's position and orientation. After the drone's flight control system executes the landing guidance command, it can adjust the drone's orientation and position so that the drone's position and orientation meet a preset threshold.

2. The landing guidance method for the vehicle-mounted firefighting and rescue drone take-off and landing support platform according to claim 1, characterized in that: The coded beacon is a visible light coded beacon that uses pulse width modulation coding. It uses guiding signals with different combinations of pulse widths to characterize unique binary information.

3. The landing guidance method for the vehicle-mounted firefighting and rescue drone take-off and landing support platform according to claim 2, characterized in that: The receiver body is in the shape of an inverted square pyramid, with M×N photosensitive elements arranged in a matrix on each pyramid. There are four coded beacons, and the distribution shape of the four coded beacons is the same as the shape of the bottom surface of the receiver body.

4. The landing guidance method for the vehicle-mounted firefighting and rescue drone take-off and landing support platform according to claim 1, characterized in that: In step S1, the step of associating the guiding signal with its corresponding signal receiving element includes: In the UAV's center of gravity coordinate system, establish the position coordinates of each signal receiving element, and associate each guidance signal with the position coordinates of the corresponding signal receiving element in the UAV's center of gravity coordinate system.

5. The landing guidance method for the vehicle-mounted firefighting and rescue drone take-off and landing support platform according to claim 1, characterized in that: In step S3, the first differential operation targets the pilot signals received by each signal receiving element on any platform of the positioning receiver from the same coded beacon, thereby determining the strongest local pilot signal received by any platform from the same coded beacon; the second differential operation targets the strongest local pilot signals received by each platform of the positioning receiver from the same coded beacon, thereby determining the strongest global pilot signal received by the positioning receiver from the same coded beacon, and the relationship between the strongest local pilot signals received by each platform from the same coded beacon.

6. The landing guidance method for the vehicle-mounted firefighting and rescue drone take-off and landing support platform according to claim 5, characterized in that: In step S3, the step of determining the location of the UAV based on the difference calculation result includes: By using the strongest global guidance signal from the same coded beacon and its associated signal receiving element received by the positioning receiver, and combining the RSSI operation model, the distance between each coded beacon and the signal receiving element corresponding to its strongest global guidance signal is determined. Construct a vehicle coordinate system and determine the position coordinates of each coded beacon in the vehicle coordinate system based on the installation position of each coded beacon on the vehicle. Based on the distance between each coded beacon and the signal receiving element corresponding to its strongest global guidance signal, and combined with the position coordinates of the signal receiving element corresponding to the strongest global guidance signal of each coded beacon in the UAV's center of gravity coordinate system, the position coordinates of the UAV's center of gravity in the vehicle coordinate system are calculated, thereby determining the UAV's position.

7. The landing guidance method for the vehicle-mounted firefighting and rescue drone take-off and landing support platform according to claim 6, characterized in that: In step S3, the step of determining the direction of the UAV based on the difference calculation result includes: The distance between each coded beacon and the drone is determined based on the position coordinates of the drone's center of gravity in the vehicle coordinate system and the position coordinates of each coded beacon in the vehicle coordinate system. Based on the distance between each coded beacon and the drone, and combined with the relationship between the strongest local guidance signals received from the same coded beacon at each platform, the drone's orientation is determined, including: The direction of the drone is determined by querying a pre-calibrated mapping table. The pre-calibrated mapping table records the relationship between the strongest local guidance signals received by each platform from the same coded beacon at different distances and orientations. When the distance and the relationship between the strongest local guidance signals received by each platform from the same coded beacon are determined, the orientation of the drone can be obtained by querying the pre-calibrated mapping table.

8. A landing guidance system for a vehicle-mounted firefighting and rescue drone take-off and landing support platform, characterized in that: The system is applied to a vehicle-mounted firefighting and rescue drone take-off and landing support platform. The take-off and landing support platform is equipped with at least three unique coded beacons for transmitting guidance signals. The drone is equipped with a positioning receiver, which includes a receiver body in the shape of an inverted truncated pyramid and at least one signal receiving element for receiving guidance signals, respectively arranged on each platform of the receiver body. The system is used for guidance during the landing phase of an unmanned aerial vehicle (UAV), and the system includes: The signal acquisition module is used to acquire the guidance signal received by each signal receiving element on each platform of the positioning receiver, and associate the guidance signal with its corresponding signal receiving element; A signal decoding module is used to decode the received guidance signal and determine the correspondence between the guidance signal and each coded beacon. The signal processing module is used to perform a first differential operation and a second differential operation on the guidance signal of each coded beacon, and determine the position and direction of the UAV based on the differential operation results. The system also includes an instruction generation module, which generates landing guidance instructions based on the UAV's position and orientation. After the UAV's flight control system executes the landing guidance instructions, it can adjust the UAV's orientation and position to ensure that the UAV's orientation and position meet a preset threshold.

9. The landing guidance system for the vehicle-mounted firefighting and rescue drone take-off and landing support platform according to claim 8, characterized in that: The signal processing module performs a first differential operation on the guiding signals received by each signal receiving element on any platform of the positioning receiver from the same coded beacon, thereby determining the strongest local guiding signal received by any platform from the same coded beacon. The signal processing module performs a second differential operation on the strongest local guiding signals received by each platform of the positioning receiver from the same coded beacon, thereby determining the strongest global guiding signal received by the positioning receiver from the same coded beacon, and the relationship between the strongest local guiding signals received by each platform from the same coded beacon.

10. The landing guidance system for the vehicle-mounted firefighting and rescue drone take-off and landing support platform according to claim 8, characterized in that: The signal processing module includes a position determination unit and a direction determination unit; The position determination unit is used to determine the distance between each coded beacon and the signal receiving element corresponding to its global strongest guidance signal and its associated signal receiving element by using the positioning receiver and the RSSI calculation model; to construct a vehicle coordinate system and determine the position coordinates of each coded beacon in the vehicle coordinate system based on the installation position of each coded beacon on the vehicle; and to calculate the position coordinates of the UAV's center of gravity in the vehicle coordinate system based on the distance between each coded beacon and the signal receiving element corresponding to its global strongest guidance signal, and the position coordinates of the signal receiving element corresponding to the global strongest guidance signal of each coded beacon in the UAV's center of gravity coordinate system, thereby determining the position of the UAV. The direction determination unit is used to determine the distance between each coded beacon and the UAV based on the position coordinates of the UAV's center of gravity in the vehicle coordinate system and the position coordinates of each coded beacon in the vehicle coordinate system. Based on the distance between each coded beacon and the UAV, and combined with the relationship between the strongest local guidance signals received by each platform from the same coded beacon, the direction of the UAV is determined, including: determining the direction of the UAV by querying a pre-calibrated mapping table, wherein the pre-calibrated mapping table records the relationship between the strongest local guidance signals received by each platform from the same coded beacon at different distances and orientations, as measured and calibrated. When the distance and the relationship between the strongest local guidance signals received by each platform from the same coded beacon are determined, the orientation of the UAV can be obtained by querying the pre-calibrated mapping table.

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