Fixed-wing unmanned aerial vehicle safety control system and control method thereof

Abstract

The invention provides a fixed-wing unmanned aerial vehicle safety control system and a control method thereof. The system comprises a data processing module, a satellite navigation positioning module, a Beidou short message satellite communication module, a safety control execution module, a task control module, a flight data storage module and an independent power supply module. Wherein the satellite navigation positioning module, the Beidou short message satellite communication module, the safety control execution module, the task control module, the flight data storage module and the independent power supply module are respectively connected with the data processing module; the data processing module is connected with the fixed-wing unmanned aerial vehicle through a serial port; the safety control execution module is connected with the airborne recovery system; and the task control module is connected with the airborne task load. The integrated safety control system provided by the invention has the advantages of high integration level, low cost, generalization and the like; the measurement and control link adopts a Beidou short message satellite communication mode, and has the advantages of all weather, full coverage, high reliability and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of redundant safety control of fixed-wing unmanned aerial vehicles, and in particular to a fixed-wing unmanned aerial vehicle safety control system and a control method thereof. Background Art

[0002] During the flight of fixed-wing UAVs, when the flight of the UAV is abnormal, the flight controller will perform safety control on the abnormal flight according to different control strategies to prevent the UAV from flying out of the safe zone or into the no-fly zone, causing huge losses to the UAV or other important facilities. At present, the safety control of fixed-wing UAVs mainly relies on the flight controller. When the flight controller is abnormal, the UAV will be out of control, which poses a huge safety hazard. Summary of the invention

[0003] Purpose of the invention: In order to improve the safety and reliability of flight support, the present invention provides a fixed-wing UAV safety control system and a control method thereof. The present invention is a redundant safety control method for fixed-wing UAVs that can realize abnormal flight controllers.

[0004] The system includes a data processing module, a satellite navigation and positioning module, a Beidou short message satellite communication module, a security execution module, a mission control module, a flight data storage module and an independent power supply module; Beidou short message communication has the advantages of all-weather, all-time, long distance and low cost, and the Beidou short message communication link is independent of the airborne measurement and control link.

[0005] Wherein, the satellite navigation and positioning module, Beidou short message satellite communication module, security and control execution module, mission control module, flight data storage module and independent power supply module are respectively connected to the data processing module;

[0006] The data processing module is connected to the fixed-wing UAV via a serial port;

[0007] The security control execution module is connected to the airborne recovery system;

[0008] The mission control module is connected to the onboard mission payload.

[0009] The airborne recovery system includes a parachute canopy opening mechanism, a shock-absorbing airbag and a recovery parachute throwing mechanism; the data processing module is controlled by a microprocessor, and can receive information sent by other modules and drones inside the safety control system in real time, perform analysis and processing operations, and control the execution of security control functions of the corresponding modules according to the operation results.

[0010] The satellite navigation and positioning module is used to receive satellite signals and calculate the current position, speed and positioning of the drone in real time, and then transmit them to the data processing module;

[0011] The Beidou short message satellite communication module is used to receive Beidou short message remote control instructions from the ground, and then transmit them to the data processing module; it is also used to send Beidou short message telemetry data from the data processing module, and then transmit them to the ground data processing terminal.

[0012] The security control execution module is used to control the voltage trigger channel or relay control channel on the drone to perform corresponding security control according to the signal output by the data processing module.

[0013] The mission control module includes multiple voltage output control channels, multiple relay control channels and payload serial port channels, which are used to expand the control of different payloads of the UAV;

[0014] The flight data storage module includes a storage chip for storing the flight data of the UAV for subsequent reading and analysis of the flight situation.

[0015] The independent power supply module includes a high-density lithium battery (such as a ternary lithium battery), an isolated power supply module (DC-DC power supply module, such as FDW10HJ24BS5T) and a multi-stage power conversion chip (such as REF5025, SPX29300T-3.3), which is used to provide the voltage required for the operation of each module inside the safety control system.

[0016] The present invention also provides a fixed-wing UAV safety control method, comprising the following steps:

[0017] Step 1: After the safety control system is powered on, configure the safety control area and other configuration items (including handshake communication interruption time, safety time beyond the safety zone, safety speed, etc.) according to the UAV flight route planning;

[0018] The security control area includes a safety zone and a warning zone. The safety zone is a convex polygonal area formed by N sequentially arranged longitude and latitude coordinates. The warning zone is the area between the convex polygonal area formed by M sequentially arranged longitude and latitude coordinates and the safety zone. The no-fly zone is an area outside the security control area. The values ​​of N and M are positive integers not less than 3.

[0019] Step 2: After the fixed-wing UAV system is powered on, the safety control system performs real-time handshake communication with the UAV through the serial port and detects the working status of the UAV flight controller in real time;

[0020] Step 3: When the safety control system determines that the flight controller is abnormal, the abnormality determination principle is that the serial port handshake communication interruption time exceeds the preset time, and the safety control system enters the autonomous safety control logic;

[0021] Step 4: When the safety control system determines that a Beidou short message control instruction is received, the safety control system enters the instruction security control logic;

[0022] Step 5: During the flight of the drone, the safety control system communicates with the drone in real time through the serial port. The data processing module controls different mission loads through the mission control module according to the received mission control data; the multi-channel voltage output control channel can control the voltage trigger mission load; the payload serial port channel can control the serial communication mission load; the multi-channel relay control channel can control the power supply and switch tasks of the payload;

[0023] Step 6: The flight data storage module and the UAV telemetry data constitute a flight data storage redundancy mechanism, receive the flight data sent by the UAV flight controller, store the flight data in the storage chip, and provide a data reading interface to meet the needs of flight data analysis.

[0024] In step 3, the autonomous security control logic includes the following steps:

[0025] Step 3-1, analyzing whether the satellite navigation and positioning module is positioned. If the satellite navigation and positioning module is not positioned, the autonomous security control is in a disabled state, otherwise, the autonomous security control is in an enabled state;

[0026] Step 3-2, the safety control system executes the safety control area judgment algorithm, tracks the current position of the drone in real time through the satellite navigation positioning module, and automatically determines the position of the drone in the safety control area according to the pre-bound safety control area vertices; at the same time, the safety control system transmits the status information of the safety control system in real time through the Beidou short message link;

[0027] Step 3-3, determine the current location of the drone. If the drone has not flown out of the safety zone, the drone is marked as being in the safety zone, and the safety control system continues to monitor the drone's location; at the same time, determine the drone's speed. If it does not reach the safety speed, return to step 3-3; when the drone speed reaches the safety speed, the safety control system controls the drone to stop and open the parachute, and jumps to step 3-5;

[0028] Step 3-4, determine the current location of the drone. If the drone exceeds the safety zone, the safety control system controls the drone to stop, marking the drone as being in the warning zone. The safety control system transmits a flashing alarm message and starts timing to determine whether the time outside the safety zone exceeds the preset safety time. If it does not exceed the preset safety time, determine whether the drone speed reaches the safe speed. If it reaches the safe speed, the safety control system controls the drone to open the parachute. If it does not reach the safe speed, the safety control system continues to monitor. If it exceeds the preset safety time, the safety control system controls the drone to open the parachute and jumps to step 3-5.

[0029] Step 3-5, determine the current location of the drone. If the drone flies into a no-fly zone, mark the drone as being in the no-fly zone, and control the drone to drop a parachute; otherwise, the safety control system continues to monitor;

[0030] In step 3-2, the security control area determination algorithm includes the following steps:

[0031] Step 3-2-1, define points and vertices of the safe zone:

[0032] Select the point to be judged as P(x0,y0), (x0,y0) is the coordinate of P; the safe zone is a convex polygon, and the vertices of the convex polygon are sorted counterclockwise or clockwise as V1(x1,y1), V2(x2,y2), ..., V n (x n ,y n );V n (x n ,y n ) is the nth vertex of the convex polygon;

[0033] Step 3-2-2, calculate the edge vector and the point-to-edge vertex vector:

[0034] Each side of the safe zone is V i V i+1 , the edge vector from the i-th vertex to the i+1-th vertex Where V n+1 = V1 is a closed convex polygon, (x i ,y i ) represents the coordinates of the i-th vertex, i ranges from 1 to n; the vertex V to be determined from the point P to each edge i The vector is

[0035] Step 3-2-3, calculate the result of the cross product of each pair of vectors

[0036] Step 3-2-4, determine whether the signs of all vector cross product results are consistent:

[0037] If the signs of all the vector cross products are consistent, then point P is inside the safe zone; if the signs of all the vector cross products are inconsistent, then point P is outside the safe zone; it is agreed in advance that if point P is on the edge of the safe zone, then point P is not considered to be inside the safe zone;

[0038] Step 3-2-5, determine whether point P is in the warning zone or in the no-fly zone: If point P is not in the safe zone but does not exceed the boundary of the warning zone, then point P is in the warning zone; otherwise, point P is in the no-fly zone.

[0039] In step 4, the instruction security control logic includes the following steps:

[0040] Step 4-1, the security control system receives the Beidou short message security control instruction;

[0041] Step 4-2, verify the received short message data: first verify the data frame header, then verify the short message airborne terminal address, and then perform CRC (Cyclic Redundancy Check, cyclic redundancy check) cyclic redundancy check. If the check passes, go to step 4-3, otherwise return to step 4-1;

[0042] Step 4-3, obtain the parsed instruction according to the parsed Beidou short message content, and perform corresponding security control actions: if the parsed Beidou short message is a parking instruction, the safety control system controls the drone to stop; if the parsed Beidou short message is a recovery instruction, the safety control system controls the drone to open the parachute; if the parsed Beidou short message is a parachute throwing instruction, the safety control system controls the drone to throw the parachute.

[0043] Beneficial effects: The present invention provides a fixed-wing UAV safety control system and a control method thereof, which can effectively improve the safety and reliability of the fixed-wing UAV during flight.

[0044] At present, the redundant safety control of drones in the market usually adopts the backup of key airborne equipment, including flight controllers, airborne measurement and control links, airborne power supplies and other equipment, which takes up a lot of space, is also very expensive, and requires customized development. In addition, airborne communication links often use customized dedicated links or base station networks. The present invention provides an integrated safety control system with the advantages of high integration, low cost, and generalization; the measurement and control link adopts the Beidou short message satellite communication method, which has the advantages of all-weather, full coverage, and high reliability.

[0045] The safety control system of the present invention works independently of the UAV flight control system and is suitable for high-speed, medium-speed and low-speed fixed-wing UAVs. The safety control system is designed with two modes: autonomous safety control and command safety control. The safety control mode is flexible and easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, and the above and other advantages of the present invention will become more clear.

[0047] Figure 1 This is a block diagram of the fixed-wing UAV safety control system provided by the present invention.

[0048] Figure 2 This is a schematic diagram of the security control area of ​​the fixed-wing UAV security control system provided by the present invention.

[0049] Figure 3 This is a schematic diagram of the security zone determination algorithm for the fixed-wing UAV security control system provided by the present invention.

[0050] Figure 4 The invention provides an automatic safety control workflow for the fixed-wing UAV safety control system.

[0051] Figure 5 The invention provides a fixed-wing UAV safety control system command security control workflow. DETAILED DESCRIPTION

[0052] like Figure 1 As shown, an embodiment of the present invention provides a fixed-wing UAV safety control system, including a data processing module, a satellite navigation and positioning module, a Beidou short message satellite communication module, a security execution module, a mission control module, a flight data storage module and an independent power supply module.

[0053] Among them, the satellite navigation and positioning module, Beidou short message satellite communication module, security and control execution module, mission control module, flight data storage module and independent power supply module are respectively connected to the data processing module; the data processing module is connected to the fixed-wing UAV through the serial port; the security and control execution module is connected to the airborne recovery system (parachute canopy opening mechanism, shock-absorbing airbag and recovery parachute throwing mechanism); the mission control module is connected to the airborne mission payload.

[0054] The data processing module is the control core of the safety control system. The data processing module is controlled by a microprocessor and can receive information sent by other modules and drones inside the safety control system in real time, perform analysis and processing operations, and control the execution of security control and other functions of the corresponding modules based on the processing and operation results.

[0055] The satellite navigation and positioning module is used to receive satellite signals and calculate the current position, speed, positioning status and other navigation information of the drone in real time, and then transmit it to the data processing module.

[0056] The Beidou short message satellite communication module is used to receive Beidou short message remote control instructions from the ground, and then transmit them to the data processing module; or send Beidou short message telemetry data from the data processing module, and then transmit them to the ground data processing terminal.

[0057] The security control execution module is used to control the voltage trigger channel or relay control channel on the drone to perform corresponding security control according to the signal output by the data processing module.

[0058] The mission control module includes multiple voltage output control channels, multiple relay control channels and payload serial port channels, which are used to expand the carrying control of different payloads of the UAV.

[0059] The flight data storage module includes a large-capacity storage chip for storing the flight data of the UAV for subsequent reading and analysis of the flight situation.

[0060] The independent power supply module includes a high-density lithium battery (such as a ternary lithium battery), an isolated power supply module (DC-DC power supply module, such as FDW10HJ24BS5T) and a multi-stage power conversion chip (such as REF5025, SPX29300T-3.3), which is used to provide the voltage required for the operation of each module inside the safety control system.

[0061] To achieve the above-mentioned and other related purposes, the present invention provides a fixed-wing UAV safety control method, comprising the following steps:

[0062] Step 1: After the safety control system is powered on, configure the safety control area and other configuration items according to the UAV flight route planning (including handshake communication interruption time T1, safety time beyond the safety zone T2, safety speed V S The security control area includes the safety area and the warning area. The safety area is a convex polygon area composed of N (N ≥ 3) latitude and longitude coordinates arranged in sequence. The vertices of the safety area boundary are recorded as V1 (x1, y1), V2 (x2, y2), ..., V n (x n ,y n ); the warning area is the area between the safety area and the convex polygon area formed by the sequentially arranged M (M ≥ 3) longitude and latitude coordinates. The boundary vertices of the warning area are recorded as W1(x1, y1), W2(x2, y2), ..., W m (x m ,y m ); the no-fly zone is the area outside the security control area. Figure 2 shown.

[0063] Step 2: After the fixed-wing UAV system is powered on, the safety control system performs real-time handshake communication with the UAV through the serial port and detects the working status of the UAV flight controller in real time.

[0064] Step 3, when the fixed-wing UAV safety control system determines that the flight controller is abnormal, the abnormality judgment principle is that the serial port handshake communication interruption time T exceeds the preset time T1 (for example, 10 seconds), that is, when T>T1, the safety control system enters the autonomous safety control logic.

[0065] like Figure 4 As shown, the autonomous security control logic includes the following steps:

[0066] Step 3-1, analyzing whether the satellite navigation and positioning module is positioned. If the satellite navigation and positioning module is not positioned, the autonomous security control is in a disabled state to avoid misoperation. Otherwise, the autonomous security control is in an enabled state;

[0067] In step 3-2, the safety control system executes the safety control area judgment algorithm, and tracks the current position of the drone in real time through the internal high-precision satellite navigation and positioning module. The longitude and latitude coordinates are marked as point P (x0, y0). According to the pre-bound safety control area vertices, the safety control system automatically determines the position of the drone in the safety control area. At the same time, the safety control system transmits the status information of the safety control system in real time through the Beidou short message link, including drone positioning information, safety control execution status and other information.

[0068] Specifically, the security control area determination algorithm includes the following steps:

[0069] Step 3-2-1, define points and vertices of the safe zone:

[0070] The point to be judged is selected as P(x0,y0); the safe zone is a convex polygon, and its vertices are sorted counterclockwise or clockwise as V1(x1,y1), V2(x2,y2), ..., V n (x n ,y n );

[0071] Step 3-2-2, calculate the edge vector and the point-to-edge vertex vector:

[0072] Each side of the safe zone is V i V i+1 , represents the edge vector from the ith vertex to the i+1th vertex (where V n+1 = V1 is a closed convex polygon), the edge vector is calculated as To be determined point P to each edge vertex V i The vector is

[0073] Step 3-2-3, calculate the vector cross product:

[0074] Calculate the cross product of each pair of vectors

[0075] Step 3-2-4, determine whether the signs of all vector cross product results are consistent:

[0076] If the signs of all the vector cross products are consistent, then point P is inside the safe zone; if the signs of all the vector cross products are inconsistent, then point P is outside the safe zone; it is agreed in advance that if point P is on the edge of the safe zone, it is not considered to be inside the safe zone. Figure 3 As shown in the figure, the safe zone is set to be arranged counterclockwise. The vectors from point A to the edge vertices V1, V2, V3, V4, and V5 have the same sign as the cross product result of the corresponding edge vector, so point A is inside the safe zone. For point B, the cross product result of the five vectors from it to the edge vertices and the corresponding edge vector is The result sign is inconsistent with the others, so point B is not inside the safe zone;

[0077] Step 3-2-5, similarly, it can be determined whether point P is in the warning zone or the no-fly zone. If point P is not in the safe zone but does not exceed the boundary of the warning zone, then point P is in the warning zone, otherwise, point P is in the no-fly zone.

[0078] Step 3-3, determine the current location of the drone. If the drone has not flown out of the safety zone, the drone is marked as being in the safety zone, and the safety control system continues to monitor the drone's position. At the same time, determine the drone's speed. When it does not reach the safe speed, return to step 3-3. When the drone speed reaches the safe speed, the safety control system controls the drone to stop, open the parachute, and jump to step 3-5.

[0079] Step 3-4, determine the current location of the drone. If the drone exceeds the safety zone, the safety control system controls the drone to stop, marking the drone in the warning zone. The safety control system transmits a flashing alarm message and starts timing to determine whether the time T outside the safety zone exceeds the preset safety time T2 (for example, 20 seconds); if it does not exceed the preset safety time T<T2, determine whether the drone speed V reaches the safety speed V S , if the safe speed V≤V S , the safety control system controls the drone to open the parachute; if the safety speed is not reached, the safety control system continues to monitor. If the predetermined safety time T2 is exceeded, that is, T≥T2, the safety control system controls the drone to open the parachute; jump to step 3-5.

[0080] Step 3-5, determine the current location of the drone. If the drone flies into a no-fly zone, mark the drone as being in the no-fly zone, and control the drone to drop a parachute; otherwise, the safety control system continues to monitor;

[0081] Step 4: When the fixed-wing UAV safety control system determines that it has received a Beidou short message control command, the safety control system enters the command security control logic.

[0082] like Figure 5 As shown, in step 4, the instruction security control logic includes the following steps:

[0083] Step 4-1, the safety control system receives Beidou short message safety control instructions, such as "parking", "recovery", and "parachute throwing" instructions;

[0084] Step 4-2, verify the received short message data, specifically, first verify the data frame header, then verify the short message airborne terminal address, and then perform CRC check, if the check passes, go to step 4-3, if not, return to step 4-1;

[0085] Step 4-3, the parsed Beidou short message content is used to perform corresponding security control actions according to the parsed instructions; specifically, if the parsed Beidou short message is a parking instruction, the safety control system controls the drone to stop, and the drone stops by cutting off the power supply of the engine controller or the engine oil pump through the relay channel; if the parsed Beidou short message is a recovery instruction, the safety control system controls the drone to open the parachute, and the drone parachute opening is that the voltage output channel controls the parachute opening canopy mechanism on the drone to actuate, so that the recovery parachute opens; if the parsed Beidou short message is a parachute throwing instruction, the safety control system controls the drone to throw the parachute, and the drone parachute throwing voltage output channel controls the parachute throwing mechanism on the drone to actuate, so that the recovery parachute is separated from the drone.

[0086] Step 5: During the flight of the drone, the safety control system communicates with the drone in real time through the serial port. The data processing module controls different mission payloads through the mission control module based on the received mission control data. The voltage output control channel can control voltage-triggered mission payloads (such as tracer tubes and decoy bombs); the payload serial port channel can control serial communication mission payloads (such as microwave sources and jammers); the relay channel can control the power supply and switch tasks of the payload;

[0087] Step 6: The flight data storage module of the safety control system and the UAV telemetry data form a flight data storage redundancy mechanism, receive the flight data sent by the UAV flight controller, store it in the storage chip, and provide a data reading interface to meet the needs of flight data analysis.

[0088] The present invention provides a fixed-wing UAV safety control system and a control method thereof. There are many methods and ways to implement the technical solution. The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention. All components not specified in this embodiment can be implemented by existing technologies.

Claims

1. A fixed-wing UAV safety control system, characterized in that: It includes data processing module, satellite navigation and positioning module, Beidou short message satellite communication module, security execution module, mission control module, flight data storage module and independent power supply module; Wherein, the satellite navigation and positioning module, Beidou short message satellite communication module, security and control execution module, mission control module, flight data storage module and independent power supply module are respectively connected to the data processing module; The data processing module is connected to the fixed-wing UAV via a serial port; The security control execution module is connected to the airborne recovery system; The mission control module is connected to the onboard mission payload.

2. The system according to claim 1, characterized in that The airborne recovery system includes a parachute canopy opening mechanism, a shock-absorbing airbag and a recovery parachute throwing mechanism; the data processing module is controlled by a microprocessor, and can receive information sent by other modules and drones inside the safety control system in real time, perform analysis and processing operations, and control the execution of security control functions of the corresponding modules according to the operation results.

3. The system according to claim 2, characterized in that The satellite navigation and positioning module is used to receive satellite signals and calculate the current position, speed and positioning of the drone in real time, and then transmit them to the data processing module; The Beidou short message satellite communication module is used to receive Beidou short message remote control instructions from the ground, and then transmit them to the data processing module; it is also used to send Beidou short message telemetry data from the data processing module, and then transmit them to the ground data processing terminal.

4. The system according to claim 3, characterized in that The security control execution module is used to control the voltage trigger channel or relay control channel on the drone to perform corresponding security control according to the signal output by the data processing module.

5. The system according to claim 4, characterized in that The mission control module includes multiple voltage output control channels, multiple relay control channels and payload serial port channels, which are used to expand the control of different payloads of the UAV; The flight data storage module includes a storage chip for storing the flight data of the UAV for subsequent reading and analysis of the flight situation.

6. The system according to claim 5, characterized in that The independent power supply module includes a high-density lithium battery, an isolated power supply module and a multi-stage power conversion chip, and is used to provide the voltage required for the operation of each module inside the safety control system.

7. A method for controlling a fixed-wing unmanned aerial vehicle using the system according to any one of claims 1 to 6, characterized in that: The steps include: Step 1: After the safety control system is powered on, configure the safety control area and other configuration items according to the UAV flight route planning; The security control area includes a safety zone and a warning zone. The safety zone is a convex polygonal area formed by N sequentially arranged longitude and latitude coordinates. The warning zone is the area between the convex polygonal area formed by M sequentially arranged longitude and latitude coordinates and the safety zone. The no-fly zone is an area outside the security control area. The values ​​of N and M are positive integers not less than 3. Step 2: After the fixed-wing UAV system is powered on, the safety control system performs real-time handshake communication with the UAV through the serial port and detects the working status of the UAV flight controller in real time; Step 3: When the safety control system determines that the flight controller is abnormal, the abnormality determination principle is that the serial port handshake communication interruption time exceeds the preset time, and the safety control system enters the autonomous safety control logic; Step 4: When the safety control system determines that a Beidou short message control instruction is received, the safety control system enters the instruction security control logic; Step 5: During the flight of the drone, the safety control system communicates with the drone in real time through the serial port, and the data processing module controls different mission loads through the mission control module according to the received mission control data; the multi-channel voltage output control channel can control the voltage-triggered mission load; The load serial port channel can control the serial communication type task load; the multi-channel relay control channel can control the power supply and switch type tasks of the load; Step 6: The flight data storage module and the UAV telemetry data constitute a flight data storage redundancy mechanism, receive the flight data sent by the UAV flight controller, store the flight data in the storage chip, and provide a data reading interface to meet the needs of flight data analysis.

8. The method according to claim 7, characterized in that In step 3, the autonomous security control logic includes the following steps: Step 3-1, analyzing whether the satellite navigation and positioning module is positioned. If the satellite navigation and positioning module is not positioned, the autonomous security control is in a disabled state, otherwise, the autonomous security control is in an enabled state; Step 3-2, the safety control system executes the safety control area judgment algorithm, tracks the current position of the drone in real time through the satellite navigation positioning module, and automatically determines the position of the drone in the safety control area according to the pre-bound safety control area vertices; at the same time, the safety control system transmits the status information of the safety control system in real time through the Beidou short message link; Step 3-3, determine the current location of the drone. If the drone has not flown out of the safety zone, the drone is marked as being in the safety zone, and the safety control system continues to monitor the drone's location; at the same time, determine the drone's speed. If it does not reach the safety speed, return to step 3-3; when the drone speed reaches the safety speed, the safety control system controls the drone to stop and open the parachute, and jumps to step 3-5; Step 3-4, determine the current location of the drone. If the drone exceeds the safety zone, the safety control system controls the drone to stop, marking the drone as being in the warning zone. The safety control system transmits a flashing alarm message and starts timing to determine whether the time of exceeding the safety zone exceeds the preset safety time. If the preset safety time is not exceeded, it is determined whether the speed of the drone reaches the safety speed. If the speed reaches the safety speed, the safety control system controls the drone to open the parachute. If the safe speed is not reached, the safety control system will continue to monitor; If the preset safety time is exceeded, the safety control system controls the drone to open the parachute and jumps to steps 3-5; Step 3-5, determine the current location of the drone. If the drone flies into a no-fly zone, mark the drone as being in the no-fly zone, and the safety control system controls the drone to drop a parachute; otherwise, the safety control system continues to monitor.

9. The method according to claim 8, characterized in that In step 3-2, the security control area determination algorithm includes the following steps: Step 3-2-1, define points and vertices of the safe zone: Select the point to be judged as P(x0,y0), (x0,y0) is the coordinate of P; the safe zone is a convex polygon, and the vertices of the convex polygon are sorted counterclockwise or clockwise as V1(x1,y1), V2(x2,y2), ..., V n (x n ,y n );V n (x n ,y n ) is the nth vertex of the convex polygon; Step 3-2-2, calculate the edge vector and the point-to-edge vertex vector: Each side of the safe zone is V i V i+1 , the edge vector from the i-th vertex to the i+1-th vertex Where V n+1 = V1 is a closed convex polygon, (x i ,y i ) represents the coordinates of the i-th vertex, i ranges from 1 to n; the vertex V to be determined from the point P to each edge i The vector is Step 3-2-3, calculate the result of the cross product of each pair of vectors Step 3-2-4, determine whether the signs of all vector cross product results are consistent: If the signs of all the vector cross products are consistent, then point P is inside the safe zone; if the signs of all the vector cross products are inconsistent, then point P is outside the safe zone; it is agreed in advance that if point P is on the edge of the safe zone, then point P is not considered to be inside the safe zone; Step 3-2-5, determine whether point P is in the warning zone or in the no-fly zone: if point P is not in the safe zone but does not exceed the boundary of the warning zone, then point P is in the warning zone; otherwise, point P is in the no-fly zone.

10. The method according to claim 9, characterized in that In step 4, the instruction security control logic includes the following steps: Step 4-1, the security control system receives the Beidou short message security control instruction; Step 4-2, verify the received short message data: first verify the data frame header, then verify the short message airborne terminal address, and then perform CRC cyclic redundancy check. If the check passes, go to step 4-3. If it fails, return to step 4-1. Step 4-3, obtain the parsed instruction according to the parsed Beidou short message content, and perform corresponding security control actions: if the parsed Beidou short message is a parking instruction, the safety control system controls the drone to stop; if the parsed Beidou short message is a recovery instruction, the safety control system controls the drone to open the parachute; if the parsed Beidou short message is a parachute throwing instruction, the safety control system controls the drone to throw the parachute.

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