Dual-data-link unmanned aerial vehicle two-station cooperative control and control right switching method

Abstract

The invention belongs to the technical field of mechanical design, and discloses a dual-data-link unmanned aerial vehicle two-station cooperative control and control right switching method, which comprises the following steps that: step 1, an unmanned aerial vehicle is electrified and initialized and is connected with a station A, the station A enters a single-station remote control telemetering mode, and a station B enters a waiting state; 2, judging whether the unmanned aerial vehicle enters a cooperative control or control right switching area or not, if so, adjusting the flight state, and otherwise, maintaining the step 2; 3, the station B enters a telemetering-only mode; 4, the A station B chain is disconnected with the unmanned aerial vehicle, the B station B chain is connected with the unmanned aerial vehicle, and a two-station one-machine cooperative control mode is entered; 5, the control right is switched from the A chain of the A station to the B chain of the B station; step 6, the station A enters a telemetering-only mode; and 7, the station B enters a single-station remote control telemetering mode, the station B controls the station B and the unmanned aerial vehicle to return to a normal channel, and the station A exits the telemetering-only mode.

Description

Technical Field

[0001] The invention belongs to the technical field of remote control and telemetry of unmanned aerial vehicles, and in particular relates to a method for coordinated control and control right switching of two stations of a dual-data link unmanned aerial vehicle. Background Art

[0002] With the continuous improvement of the design and manufacturing level of unmanned aerial vehicles in my country, their application scenarios are becoming more and more extensive, such as forest fire fighting, maritime inspections, material transportation and other fields. In some special scenarios, technical requirements are put forward for the expansion of the range of unmanned aerial vehicles, long-distance low-altitude operations, and remote take-off and landing. In this context, how to safely and conveniently realize the coordinated control and control rights switching of unmanned aerial vehicles between different control stations has become one of the research focuses in the field of remote control and telemetry of unmanned aerial vehicles. At present, there are some related methods for the control rights switching of unmanned aerial vehicles in China:

[0003] The method proposed in application number 202211459268.2 "A method for handing over control of a drone between a portable control station and a ground control station" is as follows: the master station sets the data link uplink to silent, and after the slave station receives the telemetry data and determines that the data link uplink is unlocked, it sets the slave station data link uplink to work and re-establishes a connection with the drone, thereby switching control from the master station to the slave station. This method is suitable for drones that use a single data link for remote control and telemetry, and there is a control window period during the switching process when the drone is disconnected from both stations.

[0004] The method proposed in application number 202110929094.0 "A method for two ground stations to collaboratively control a drone" is as follows: the control station establishes uplink and downlink links with both the main and secondary links of the drone, the request station establishes a downlink link with the main link of the drone, and establishes uplink and downlink links with the secondary link; and a scheduling module dedicated to collaborative control is set up, which communicates with the control station, the request station, the flight control module and the task module respectively, and the scheduling module is used to receive and forward requests, response messages and control data; the request station initiates a control request, and the control station switches the platform control or payload control to the request station after granting authorization. This method solves the problem of the control window period, but requires the secondary link used to support multi-point communication. The price of this type of data link is higher than that of the point-to-point communication data link, and the method adds a scheduling module hardware device, which further increases the system cost.

[0005] Some other methods also basically require the data link to support multi-point communication, which also brings about the problem of increased system cost. Summary of the invention

[0006] Purpose of the invention: In view of the above problems and taking into account the actual situation that most medium and large unmanned aerial vehicles are currently equipped with two or more sets of data link equipment, a method for two-station collaborative control and control right switching of dual-data link unmanned aerial vehicles is proposed. The data links used in this method are all point-to-point data links, and no new related hardware equipment is required. It not only solves the problem of control right window period, but also realizes communication interaction between the two stations, thereby realizing a collaborative control and control right switching method that is safe, relatively low-cost, and simple to operate.

[0007] According to the characteristics of remote control and telemetry of dual data link unmanned aerial vehicles, the present invention proposes a method for coordinated control and control right switching between two stations of dual data link unmanned aerial vehicles, and carries out risk identification and risk reduction measures.

[0008] Technical Solution

[0009] A method for coordinated control and control right switching of two stations of a dual data link unmanned aerial vehicle, the process is as follows:

[0010] Step 1: The UAV is powered on and initialized, and a connection is established with station A. Station A enters the single-station remote control and telemetry mode, and station B enters the waiting state;

[0011] Step 2: Determine whether the UAV has entered the cooperative control or control right switching area. If so, adjust the flight state; otherwise, maintain step 2.

[0012] Step 3: Station B enters telemetry-only mode;

[0013] Step 4: Station A and B are disconnected from the UAV, and Station B and B are connected to the UAV, entering the two-station-one-machine collaborative control mode;

[0014] Step 5: Switch control from Chain A of Station A to Chain B of Station B;

[0015] Step 6: Station A enters telemetry-only mode;

[0016] Step 7: Station B enters single-station remote control and telemetry mode. Station B controls itself and the UAV to restore the normal channel, and Station A exits telemetry-only mode.

[0017] Furthermore, in step one, the UAV establishes a connection with station A and transmits the current remote control signal source information.

[0018] Furthermore, in step two, after the UAV enters the collaborative control or control switching area, it maintains a hovering or straight-and-level flight state at a small or medium speed.

[0019] Furthermore, in step 2, after the unmanned aerial vehicle enters the collaborative control or control switching area, station B powers on both chains, and sets the uplink of chain A and chain B to silent state, and the downlink of chain A and chain B enters the switching dedicated channel; station A switches both the uplink and downlink of chain A and chain B to the switching dedicated channel; at the same time, station A controls the unmanned aerial vehicle to enter the switching dedicated channel.

[0020] Further, in step three, the process is as follows:

[0021] Station A uploads the notification information about preparing to start the control right switching;

[0022] The UAV receives the notification information of preparing to start the control right switching and transmits it down;

[0023] After receiving the notification information of preparing to start the control switch, station B maintains telemetry monitoring of the unmanned aerial vehicle and enters the telemetry-only mode.

[0024] Further, in step 4, the process is as follows:

[0025] Step 1. Station A confirms that the enable signal of the external control box of Station A is in the off state, and uploads the external control box status confirmation notification information; the unmanned aerial vehicle receives the external control box status confirmation notification information and transmits the notification information down; Station B sets the control amount of each channel of the external control box of Station B to be consistent with the transmitted external control box control amount, and turns off the enable signal of the external control box of Station B;

[0026] Step 2. Station A sends a command to start the control switching program and a notification message that the control switching program has been started. After receiving the command to start the control switching program and the notification message that the control switching program has been started, the unmanned aerial vehicle starts the control switching program and transmits the status and the notification message that the control switching program has been started; Station B receives the telemetry feedback from the unmanned aerial vehicle and enters the control switching implementation procedure;

[0027] Step 3. Station A receives telemetry feedback from the UAV, sets the uplink of Station A's B-link to be silent, and uploads the uplink notification information of Station A's B-link being silent; the UAV receives the uplink notification information of Station A's B-link being silent, and transmits the notification information down; Station B receives the uplink notification information of Station A's B-link being silent, sets the uplink of Station B's B-link to work, and enters the dedicated channel for control rights and high power;

[0028] Step 4. The UAV establishes a connection with the B-link of Station B. Station B receives the telemetry feedback restored by the B-link and uploads the notification information that the B-link of Station B has established a connection. The UAV receives the notification information that the B-link of Station B has established a connection and downloads the notification information. Station A receives the notification information that the B-link of Station B has established a connection. At this time, the two-station-one-machine collaborative control mode is entered.

[0029] Further, in step five, the process is as follows:

[0030] Step 1. Station A uploads a notification message about the handover of control rights by switching the remote control signal source; the unmanned aerial vehicle receives the notification message about the handover of control rights by switching the remote control signal source and transmits the notification message to the next station; Station B receives the notification message about the handover of control rights by switching the remote control signal source and prepares to receive the control rights;

[0031] Step 2. Station B uploads the notification information of agreeing to switch the remote control signal source; the unmanned aerial vehicle receives the notification information of agreeing to switch the remote control signal source and transmits the notification information; Station A receives the feedback of the notification information of agreeing to switch the remote control signal source and implements the next step;

[0032] Step 3. Station A sends a command to switch the remote control signal source. After receiving the command to switch the remote control signal source, the unmanned aerial vehicle switches to using the remote control signal source of station B's second chain. The unmanned aerial vehicle determines whether the control station number in the remote control signal source information is legal: if it is legal, it responds to the remote control command normally and transmits the remote control signal source information with the control station number. If it is an illegal control station, it does not respond to the remote control command, transmits the illegal notification information of the control station, and triggers a return to the take-off point or the alternate landing point. Station B receives telemetry feedback such as the legality of the control station and the current remote control signal source information with the control station number. At this time, station B has control over the unmanned aerial vehicle, and the remote control signal source is station B's second chain.

[0033] Further, in step six, the process is as follows:

[0034] Step 1. Station A uploads the silent notification information of preparing to implement the uplink of Station A's chain A; the unmanned aerial vehicle receives the silent notification information of preparing to implement the uplink of Station A's chain A and transmits the notification information downward; Station B receives the silent notification information of preparing to implement the uplink of Station A's chain A and prepares to implement the next step;

[0035] Step 2. Station B uploads the information of the silent notification of the uplink of chain A; the unmanned aerial vehicle receives the information of the silent notification of the uplink of chain A and transmits the information downward; Station A receives the information of the silent notification of the uplink of chain A and gives feedback;

[0036] Step 3. Station A uploads the notification information that the uplink of Station A's A chain has been silent, and then immediately sets its own A chain uplink to be silent; the unmanned aerial vehicle receives the notification information that the uplink of Station A's A chain has been silent, and transmits the notification information down; Station B receives the notification information that the uplink of Station A's A chain has been silent, sets Station B's A chain uplink to work, and enters the control right dedicated channel with high power;

[0037] Step 4. The UAV establishes a connection with the chain A of Station B and uploads the status; Station B receives the telemetry feedback of the uplink recovery of chain A and uploads the notification information that the connection of chain A of Station B has been established; the UAV receives the notification information that the connection of chain A of Station B has been established and downloads the notification information; Station A receives the notification information that the connection of chain A of Station B has been established, and Station A keeps monitoring the telemetry data.

[0038] Further, in step seven, the process is as follows:

[0039] Step 1. Station B sends a command to switch the remote control signal source, and the UAV remote control signal source is switched to Station B's chain A; the UAV determines whether the control station number in the remote control signal source information is legal: if it is legal, it responds to the remote control command normally and transmits the remote control signal source information; if it is an illegal control station, it does not respond to the remote control command and triggers a return to the take-off point or alternate landing point; Station A keeps monitoring the telemetry data;

[0040] Step 2. Station B sends a control switching completion instruction; after receiving the control switching completion instruction, the UAV exits the control switching program and uploads the status; Station A receives feedback from the UAV exiting the control switching program and keeps monitoring the telemetry data;

[0041] Step 3. Station B switches the dual data link channel and downlink rate between itself and the UAV to the normal flight channel and rate; Station A's telemetry is interrupted and monitoring is exited. At this time, Station B enters the single-station remote control telemetry mode;

[0042] Step 4. Complete the control switching procedure, and the UAV flies according to the remote control instructions of Station B.

[0043] In summary, the beneficial effects of the present invention are as follows:

[0044] 1. A method for two-station collaborative control and control right switching suitable for unmanned aerial vehicles equipped with dual data links is proposed;

[0045] 2. The proposed method realizes one-key seamless switching of control rights, and there is no control window period caused by data link interruption and reconnection. It is highly safe and easy to operate, and the coordinated control of the unmanned aerial vehicle by the two stations is very convenient;

[0046] 3. A notification information function is proposed to achieve convenient information exchange between the two stations, greatly improving security;

[0047] 4. The method is applicable to point-to-point data links, and does not require additional hardware. It only requires the flight control software to be adapted accordingly, which will not increase system costs.

[0048] 5. Effective risk identification was performed on the two-station collaborative control and control right switching method of the unmanned aerial vehicle, and corresponding risk reduction measures were proposed to improve the operational safety of the unmanned aerial vehicle. The control right switching method of the present invention can promote the application and development of unmanned aerial vehicles in related fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a schematic diagram of a single-station remote control and telemetry mode, a one-station remote control and telemetry and a one-station telemetry-only mode, and a two-station-one-machine collaborative control mode;

[0050] Figure 2 It is a schematic diagram of the coordinated control and control right switching process of two stations of the unmanned aerial vehicle;

[0051] Figure 3 This is a schematic diagram of the composition of the UAV data link uplink data. DETAILED DESCRIPTION

[0052] Here are the steps:

[0053] Step 1. The whole UAV is powered on, and the A-chain and B-chain of station A are powered on. After the UAV establishes a data link connection with the A control station, it transmits the current remote control signal source information (control station number and link number); after the A-station establishes a data link connection with the UAV, it switches the remote control signal source to the A-chain of station A; the B-station double chain is powered off and keeps waiting. At this time, it enters the single-station remote control telemetry mode (station A).

[0054] Step 2. Control station A controls the UAV to fly to the designated area according to normal procedures. The UAV flies to the designated area for collaborative control or control right switching according to the remote control command, and then maintains a hovering or medium-speed straight-and-level flight state. Control station B powers on both chains and immediately sets both chain A and chain B uplinks to silent state, sets the downlink working channel to the dedicated channel for control right switching, sets the downlink rate to the agreed rate, and keeps waiting for telemetry data.

[0055] Step 3. Control station A sets the dual-link uplink and downlink channels to the dedicated channel for control authority switching, the downlink rate to the agreed rate, and both are in high-power working state, and uploads the notification information of preparing to start control authority switching; the unmanned aerial vehicle receives the command and notification information, and the airborne dual-link uplink and downlink enter the dedicated channel for control authority switching, the downlink rate to the specified rate, the uplink and downlink are in high-power state, and the notification information is transmitted; at this time, control station B receives the telemetry data and notification information, prepares and keeps monitoring the telemetry data. At this time, it enters the one-station remote control telemetry one-station only telemetry mode (station A remote control telemetry station B only telemetry).

[0056] Step 4. Control station A confirms that the enable signal of the external control box of station A is in the off state, and uploads the notification information of the external control box status confirmation; the unmanned aerial vehicle receives the notification information and transmits it down; control station B sets the control quantity of each channel of the external control box of this station to be consistent with the control quantity of the external control box transmitted down, and turns off the enable signal of the external control box.

[0057] Step 5. Control station A sends a command to start the control switching program and a notification message that the control switching program has been started. After receiving the command and notification message, the UAV starts the control switching program and transmits the status and notification message. Control station B receives the telemetry feedback from the UAV and enters the control switching implementation procedure.

[0058] Step 6. Control station A receives telemetry feedback from the UAV, sets the uplink of link B to be silent, and uploads notification information of link B uplink silence at station A; the UAV determines that link B is interrupted, receives notification information, and transmits link B status and notification information; control station B receives link B interruption status and notification information, sets link B uplink to work at station B, and enters the control right dedicated channel with high power.

[0059] Step 7. The UAV establishes a connection with the B-link of Station B, the B-link of Station B is restored, and the B-link status is uploaded; the B control station receives the telemetry feedback of the B-link uplink restoration and uploads the B-link connection notification information of Station B; the UAV receives the notification information and transmits it down; the A control station receives the telemetry feedback of the B-link uplink restoration of Station B and the B-link connection notification information of Station B. At this time, the two-station-one-machine collaborative control mode is entered.

[0060] Step 8. Control station A uploads a notification message about preparing to switch the remote control signal source and transfer control rights; the UAV receives the notification message and transmits it down; control station B receives the notification message and prepares to receive control rights.

[0061] Step 9. Control station B uploads a notification message agreeing to switch the remote control signal source; the UAV receives the notification message and transmits it down; control station A implements the next step after receiving the notification message feedback.

[0062] Step 10. Control station A sends a command to switch the remote control signal source; after receiving the command, the UAV switches to the remote control signal source of link B, and determines whether the control station number in the remote control signal source information is legal: if it is legal, it responds to the remote control command normally and transmits the remote control signal source information (control station number and link number); if it is an illegal control station, it does not respond to the remote control command, transmits the illegal notification information of the control station, and triggers the return to the take-off point or alternate landing point; control station B receives telemetry feedback such as the legality of the control station and the current remote control signal source information (control station number and link number). At this time, control station B has the control right of the UAV, and the remote control signal source is link B of station B. (In the two-station one-machine collaborative control mode, the control right can be switched between station A and station B multiple times. After completing the task, the control right needs to be switched to the single-station remote control telemetry mode. The following operation steps are the steps for switching the control right to control station B, and the steps for switching the control right back to control station A are shown in the attached figure).

[0063] Step 11. Control station A uploads the A-chain uplink silent notification information in preparation for implementation; the UAV receives the notification information and transmits it down; control station B receives the notification information and prepares to implement the next step.

[0064] Step 12. Control station B uploads the agreement to implement the A-chain uplink silent notification information; the UAV receives the notification information and transmits it downward; control station A receives the notification information feedback.

[0065] Step 13. Control station A uploads the notification information that the uplink of chain A of station A has been silenced, and then immediately sets the uplink of chain A to be silent; the unmanned aerial vehicle receives the notification information, determines that chain A is interrupted, and transmits the status of chain A and the notification information; control station B receives the notification information and the interruption status of chain A, sets the uplink of chain A of station B to work, and enters the dedicated channel for control rights and high power.

[0066] Step 14. The UAV establishes a connection with the A-chain of Station B, and the A-chain is restored uplink, and the A-chain status is uploaded; the B control station receives the telemetry feedback of the A-chain uplink restoration and uploads the notification information of the B-chain that the A-chain connection has been established; the UAV receives the notification information and transmits it down; the A control station receives the telemetry feedback of the A-chain uplink restoration and the B-chain that the A-chain connection has been established notification information, and the A-station keeps monitoring the telemetry data. At this time, the one-station remote control telemetry one-station only telemetry mode is entered (the B-station remote control telemetry A-station only telemetry).

[0067] Step 15. Control station B sends a command to switch the remote control signal source; the remote control signal source of the unmanned aerial vehicle is switched to chain A of station B, and determines whether the control station number in the remote control signal source information is legal: if it is legal, it responds normally to the remote control command and transmits the remote control signal source information; if it is an illegal control station, it does not respond to the remote control command and triggers a return to the take-off point or alternate landing point; control station A keeps monitoring the telemetry data.

[0068] Step 16. Control station B sends a command to complete the control switching; after receiving the command, the UAV exits the control switching program and uploads the status; control station A receives feedback from the UAV exiting the control switching program and keeps monitoring the telemetry data.

[0069] Step 17. Control station B switches the data link channels and downlink rates of chain A and chain B to the normal flight channels and rates; the UAV receives the command, the airborne data link enters the normal flight channel, and the downlink rate reaches the specified rate; control station A interrupts telemetry and exits monitoring. At this time, it enters the single-station remote control telemetry mode (station B).

[0070] Step 18. Complete the control switching procedure. Control station B completes the control switching procedure and controls the unmanned aerial vehicle according to normal procedures; the unmanned aerial vehicle flies according to the remote control instructions of station B.

[0071] When the dual data links (Chain A and Chain B) installed on the above-mentioned unmanned aerial vehicle are in use, the remote control signal source should be switched to Chain A of Station A after the unmanned aerial vehicle is initially powered on.

[0072] The above-mentioned unmanned aerial vehicle is designed with two ways to switch the remote control signal source: one is that when both links remain connected, the control station with control authority sends a "switch remote control signal source" command to actively change; the other is that when the remote control signal source link used by the unmanned aerial vehicle is interrupted, the aircraft automatically switches the remote control signal source to another link that remains connected; the interruption of both links triggers the return procedure.

[0073] When the above-mentioned unmanned aerial vehicle is in the air and the remote control signal source is switched, the legitimacy of the control station number in the new remote control signal source information will be determined; each of the above-mentioned control stations corresponds to a unique number. Before implementing the control right switch, it should be ensured that the control station number used is in the legal control station number library stored in the unmanned aerial vehicle. The legitimacy of the control station is not determined when it is on the ground.

[0074] The above-mentioned UAV data link uplink data contains two parts: remote control data and notification information. The remote control data is the remote control command sent by the control station to the UAV, and the notification information is used for information exchange between the two stations. The notification information is a function designed for information exchange between the two stations. The UAV only reads and executes the remote control command uploaded by the control station with control rights; the UAV will read the notification information uploaded by chain A and chain B at the same time, and forward it downward. In the two-station one-machine collaborative control mode, the two stations can exchange information by sending notification information.

[0075] In the above-mentioned one-station remote control and telemetry and one-station only telemetry mode, the control station with control authority can upload and receive notification information, and the control station that only monitors telemetry data can only receive notification information; in the two-station one-machine collaborative control mode, both stations can upload and receive notification information.

[0076] After the above-mentioned unmanned aerial vehicle enters the control switching program, when the dual chain interruption triggers the return, it will determine whether to return to the take-off point or the alternate landing point based on its own fuel level: if the fuel level is sufficient to return to the take-off point, it will return to the take-off point, otherwise it will return to the alternate landing point; therefore, a suitable alternate landing point must be set before the flight.

[0077] In the above-mentioned two-station-one-machine collaborative control mode, one station has control rights and the other station is in monitoring standby state. The control station with control rights can send a "switch remote control signal source" command to achieve one-click seamless switching of control rights to another station. After the control rights are switched, the two-station-one-machine collaborative control mode remains in place.

[0078] The above-mentioned unmanned aerial vehicle determines the data link interruption as follows: if the data link uplink is interrupted, the unmanned aerial vehicle determines that the link is interrupted.

[0079] The above-mentioned UAV external control box is only used for manual control of the UAV. When using the external control box for control, its enable signal should be in the on state. When the external control box enable signal is in the off state, the UAV does not respond to the control value of the external control box. During the control right switching process, the enable signals of the external control boxes of both stations must be in the off state.

[0080] Although the above-mentioned method of coordinated control and control right switching of two stations of unmanned aerial vehicles is simple to operate and highly safe, there are still certain risks in the implementation process. It is necessary to identify the risks of the process and provide risk reduction measures to further improve safety. The specific risk identification and risk reduction measures are as follows:

[0081] 1. Before the control switching procedure is started, the remote control signal of the B control station interferes with the remote control of the unmanned aerial vehicle after the data link is powered on. The handling measures are as follows: After the dual chains of the B control station are powered on, both the A chain and the B chain must be quickly set to silent mode to avoid signal interference caused by both remote control uplinks being turned on, affecting flight safety.

[0082] 2. An abnormality occurs during the control switching process, and both control stations A and B lose connection with the UAV. Disposal measures: Set a suitable alternate landing point before implementing the control switching flight mission. If both chain A and chain B are interrupted for more than the specified time during the control switching process, triggering an emergency return, the UAV returns to the take-off point or alternate landing point based on its own fuel level: if the fuel level is sufficient to return to the take-off point, it returns to the take-off point, otherwise it returns to the alternate landing point; use third-party communication methods (such as wired telephones, wireless telephones, satellite phones, etc.) to strengthen communication and feedback on each other's status.

[0083] 3. During the implementation of the control switch, the signals of chain A and chain B are in an unstable state. The handling measures are: try to avoid performing the control switch operation when the data link is unstable; if it is necessary to perform the control switch operation in this state, use a third-party communication method (such as wired telephone, wireless telephone, satellite phone, etc.) to strengthen the communication and feedback on each other's status.

[0084] 4. Technical requirements for test pilots: The operators in the control station should have sufficient experience in operating unmanned aerial vehicles and be familiar with the control switching process steps.

[0085] 5. Data link requirements: The dedicated channel for control authority switching can only be used during the implementation of control authority switching and is prohibited from being used during other flight missions to avoid misjudgment and affecting flight safety.

Claims

1. A method for coordinated control and control right switching of two stations of a dual data link unmanned aerial vehicle, characterized in that: The process is as follows: Step 1: The UAV is powered on and initialized, and a connection is established with station A. Station A enters the single-station remote control and telemetry mode, and station B enters the waiting state; Step 2: Determine whether the UAV has entered the cooperative control or control right switching area. If so, adjust the flight state; otherwise, maintain step 2. Step 3: Station B enters telemetry-only mode; Step 4: Station A and B are disconnected from the UAV, and Station B and B are connected to the UAV, entering the two-station-one-machine collaborative control mode; Step 5: Switch control from Chain A of Station A to Chain B of Station B; Step 6: Station A enters telemetry-only mode; Step 7: Station B enters single-station remote control and telemetry mode. Station B controls itself and the UAV to restore the normal channel, and Station A exits telemetry-only mode.

2. The method according to claim 1, characterized in that: In step 1, the UAV establishes a connection with station A and transmits the current remote control signal source information.

3. The method according to claim 1, characterized in that: In step 2, after the UAV enters the collaborative control or control switching area, it maintains a hovering or straight-and-level flight at a low or medium speed.

4. The method according to claim 1, characterized in that: In step 2, after the UAV enters the collaborative control or control switching area, station B powers on both chains and sets the uplink of chain A and chain B to silent state, while the downlink of chain A and chain B enters the switching dedicated channel; station A switches both the uplink and downlink of chain A and chain B to the switching dedicated channel; at the same time, station A controls the UAV to enter the switching dedicated channel.

5. The method according to claim 1, characterized in that: In step three, the process is as follows: Station A uploads the notification information about preparing to start the control right switching; The UAV receives the notification information of preparing to start the control right switching and transmits it down; After receiving the notification information of preparing to start the control switch, station B maintains telemetry monitoring of the unmanned aerial vehicle and enters the telemetry-only mode.

6. The method according to claim 1, characterized in that: In step 4, the process is as follows: Step 1. Control station A confirms that the enable signal of the external control box of station A is in the off state, and uploads the notification information of the status confirmation of the external control box of station A; the unmanned aerial vehicle receives the notification information and transmits it down; control station B sets the control amount of each channel of the external control box of this station to be consistent with the control amount of the external control box transmitted down, and turns off the enable signal of the external control box of station B; Step 2. The A control station sends a command to start the control right switching program and a notification message that the control right switching program has been started. After receiving the command and notification message, the UAV starts the control right switching program and transmits the status and notification message. The B control station receives the telemetry feedback from the UAV and enters the control right switching implementation program. Step 3. Control station A receives telemetry feedback from the UAV, sets the uplink of link B to be silent, and uploads notification information that link B uplink of station A has been silent; the UAV determines that link B is interrupted, receives notification information, and transmits the link B status and notification information; control station B receives link B interruption status and notification information, sets link B uplink of station B to work, and enters the control right dedicated channel and high power; Step 4. The UAV establishes a connection with link B of station B, and uploads the link B status; control station B receives telemetry feedback that link B uplink has been restored and uploads notification information that link B has been established; the UAV receives the notification information and transmits it; control station A receives telemetry feedback that link B uplink has been restored and notification information that link B has been established; at this time, the two-station-one-machine collaborative control mode is entered.

7. The method according to claim 1, characterized in that: In step five, the process is as follows: Step 1. Station A uploads a notification message about switching the remote control signal source and handing over the control right; The unmanned aerial vehicle receives the notification information of the handover of control right after the remote control signal source is switched and transmits the notification information to the next station; the station B receives the notification information of the handover of control right after the remote control signal source is switched and prepares to receive the control right; Step 2. Station B uploads the notification information of agreeing to switch the remote control signal source; The UAV receives the notification information of agreeing to switch the remote control signal source and transmits the notification information to the next step; after receiving the feedback of the notification information of agreeing to switch the remote control signal source, the A station implements the next step; Step 3. Station A sends a command to switch the remote control signal source. After receiving the command, the UAV switches to using the remote control signal source of Station B. The unmanned aerial vehicle determines whether the control station number in the remote control signal source information is legal: if it is legal, it will respond to the remote control command normally and transmit the remote control signal source information with the control station number; if it is an illegal control station, it will not respond to the remote control command, transmit the illegal notification information of the control station, and trigger the return to the take-off point or the alternate landing point; Station B receives telemetry feedback such as the current remote control signal source information of the legal control station and the control station number. At this time, Station B has control over the unmanned aerial vehicle, and the remote control signal source is Station B's B link.

8. The method according to claim 1, characterized in that: In step six, the process is as follows: Step 1. Station A uploads the silent notification information of preparing to implement the uplink of Station A's chain A; the unmanned aerial vehicle receives the silent notification information of preparing to implement the uplink of Station A's chain A and transmits the notification information downward; Station B receives the silent notification information of preparing to implement the uplink of Station A's chain A and prepares to implement the next step; Step 2. Station B uploads the information agreeing to implement the silent notification of chain A uplink; The unmanned aerial vehicle receives the agreement to implement the A-chain uplink silent notification information and transmits the notification information downward; Station A receives the agreement to implement the A-chain uplink silent notification information feedback; Step 3. Station A uploads the notification information that the uplink of Station A's A chain has been silent, and then immediately sets its own A chain uplink to be silent; the unmanned aerial vehicle receives the notification information that the uplink of Station A's A chain has been silent, and transmits the notification information down; Station B receives the notification information that the uplink of Station A's A chain has been silent, sets Station B's A chain uplink to work, and enters the control right dedicated channel with high power; Step 4. The UAV establishes a connection with the chain A of Station B and uploads the status; Station B receives the telemetry feedback of the uplink recovery of chain A and uploads the notification information that the connection of chain A of Station B has been established; the UAV receives the notification information that the connection of chain A of Station B has been established and downloads the notification information; Station A receives the notification information that the connection of chain A of Station B has been established, and Station A keeps monitoring the telemetry data.

9. The method according to claim 1, characterized in that: In step seven, the process is as follows: Step 1. Station B sends a command to switch the remote control signal source, and the UAV remote control signal source is switched to Station B's chain A; the UAV determines whether the control station number in the remote control signal source information is legal: if it is legal, it responds to the remote control command normally and transmits the remote control signal source information; if it is an illegal control station, it does not respond to the remote control command and triggers a return to the take-off point or alternate landing point; Station A keeps monitoring the telemetry data; Step 2. Station B sends a control switching completion instruction; after receiving the control switching completion instruction, the UAV exits the control switching program and uploads the status; Station A receives feedback from the UAV exiting the control switching program and keeps monitoring the telemetry data; Step 3. Station B switches the dual data link channel and downlink rate between itself and the UAV to the normal flight channel and rate; Station A's telemetry is interrupted and monitoring is exited. At this time, Station B enters the single-station remote control telemetry mode; Step 4. Complete the control switching procedure, and the UAV flies according to the remote control instructions of Station B.

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