Control system and method of unmanned aerial vehicle

Abstract

The invention discloses an unmanned aerial vehicle control system and method, and relates to the technical field of unmanned aerial vehicle control, the control system comprises a ground control end and an unmanned aerial vehicle end, the ground control end comprises a light source module, a signal coding unit and a light beam directional emission module, the unmanned aerial vehicle end comprises a photoacoustic receiving module, a signal decoding and processing unit and a flight control execution module, the system detects emitted sound waves through a photoacoustic effect, reversely deduces characteristic information of the intensity and frequency of optical signals, uses the optical signals as an information carrier, and performs photoacoustic conversion and acoustic signal processing, so that the flight control performance of the unmanned aerial vehicle is improved. According to the system, remote control over the unmanned aerial vehicle is achieved, meanwhile, a photoacoustic conversion and encoding and decoding mechanism is introduced, high-precision and long-distance transmission of control instructions of the unmanned aerial vehicle is achieved, and therefore the capacity of a receiving end for capturing weak signals is enhanced, and the system can flexibly deal with the signal attenuation problem under different illumination conditions and flight environments.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned aerial vehicle control, and in particular to a control system and method for an unmanned aerial vehicle. Background Art

[0002] With the rapid development of drone technology, drones are increasingly used in various fields, including aerial photography, logistics, agricultural monitoring, environmental monitoring, etc. In these applications, precise control of drones is crucial.

[0003] However, existing UAV control methods mainly rely on radio remote control technology, which faces huge challenges in long-distance control and electromagnetic interference. Radio signals are easily blocked by terrain and building obstacles, resulting in severe signal attenuation, which in turn causes control delays. In addition, in environments with severe electromagnetic interference, the reliability of radio remote control technology is greatly reduced. For example, near high-voltage transmission lines, in places with dense electronic equipment or in strong magnetic field environments, electromagnetic interference will distort radio signals and affect the accurate transmission of control commands, seriously threatening the flight safety and mission execution of UAVs.

[0004] In summary, the limitations of existing UAV control technology in long distances and strong electromagnetic interference environments urgently require a new control technology that utilizes the photoacoustic effect to solve these problems, so as to improve the reliability, stability and adaptability of UAV control and meet the increasingly diverse application needs. Summary of the invention

[0005] The purpose of the present invention is to make up for the shortcomings of the prior art and provide a drone control system and method. It can use the photoacoustic effect. When the light signal is irradiated to the surface of an object, the object will absorb the light energy and generate heat, and then generate sound waves. By detecting these sound waves, the characteristic information of the intensity and frequency of the light signal can be inferred. The drone control technology based on the photoacoustic effect uses the light signal as the information carrier, and realizes remote control of the drone through photoacoustic conversion and sound signal processing.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: On the one hand, a control system for an unmanned aerial vehicle, the control system includes a ground control end and an unmanned aerial vehicle end, the ground control end includes: a light source module, a signal encoding unit and a beam directional emission module, the unmanned aerial vehicle end includes: an optical acoustic receiving module, a signal decoding and processing unit and a flight control execution module;

[0007] The light source module can generate light signals of different intensities and modulation frequencies. The light source module uses a high-power laser to generate a specific light signal mode for controlling the drone, that is, the light signal intensity is set to I, the modulation frequency is f, and the coding mode function of the light signal is M(I,f), where the value range of I is Imin To I max , the value range of f is f min to f max , different combinations of I and f correspond to different control instruction encoding modes through the M(I,f) function;

[0008] The signal encoding unit is connected to the light source module and is used to convert the control instructions into corresponding light signal intensity and frequency modulation information, so that the drone end can accurately parse the control instructions, that is, define the control instruction set as C = {c1, c2, c3, ..., c n}, where c i It represents the i-th control instruction, and its signal encoding is I=I0+k1×c i , f=f0+k2×c i , where I0 and f0 are the basic intensity and frequency values, k1 and k2 are the intensity and frequency adjustment coefficients of the command respectively. The control command c is encoded through this signal i Converted into corresponding optical signal intensity I and frequency f to adjust control information:

[0009] The beam directional transmission module is used to transmit the encoded optical signal in a direction to the airspace where the drone is located, so that the optical signal covers the receiving range of the drone;

[0010] The photoacoustic receiving module is used to receive the light signal emitted by the ground control end, and after receiving the light signal, generate a corresponding sound wave signal based on the photoacoustic effect;

[0011] The signal decoding and processing unit is connected to the photoacoustic receiving module, and is responsible for decoding the sound wave signal generated by the photoacoustic receiving module, restoring it to the original control command information, and calculating the flight control parameters of the UAV according to the command. The control parameters include the flight attitude adjustment amount, the speed control amount and the heading change amount. The characteristic value of the received sound wave signal is S, and it is decoded into Where S0 is the reference value of the sound wave signal, k3 is the decoding coefficient, and the sound wave signal S is decoded and restored to the control instruction c′ i , calculate the flight control parameters according to the control instructions, that is, calculate the flight attitude adjustment amount θ as: θ = k4 × c′ i , where k4 is the attitude adjustment coefficient, and the speed control amount v is: v = v0 + k5 × c' i , where v0 is the basic speed value, k5 is the speed adjustment coefficient, and the heading change φ is: φ=k6×c′ i , where k6 is the heading adjustment coefficient;

[0012] The flight control execution module is used to drive the actuator of the UAV according to the control parameters calculated by the signal decoding and processing unit, so as to realize the precise control of the flight attitude and motion state of the UAV.

[0013] Furthermore, the coding mode function M(I,f) of the optical signal in the light source module is: Among them, w i is the weight of the i-th control instruction, I min is the minimum optical signal intensity, I max is the maximum light signal intensity, f min is the minimum modulation frequency, f max is the maximum modulation frequency, c i is the i-th control instruction, I0 is the basic intensity value, f0 is the basic frequency value, k1 is the intensity adjustment coefficient of the instruction, k2 is the frequency adjustment coefficient of the instruction, δ(x) is the instruction judgment function, which is used to indicate that when x=0, the value is 1, otherwise it is 0. Through this coding mode function M(I,f), different combinations of optical signal intensity I and modulation frequency f are mapped to specific control instructions c i ,Right now:

[0014] When the optical signal intensity I and modulation frequency f exceed the range (I min , I max ) and (f min , f max ), the encoding mode function M(I,f) returns 0, indicating invalid encoding;

[0015] When the optical signal intensity I and the modulation frequency f are within the valid range, the coding mode function M(I,f) maps I and f to a specific control instruction c through the instruction judgment function δ i Specifically, when (I-I0) / k1 and (f-f0) / k2 are both equal to one of the control instructions c i When , the encoding mode function returns the weight w of the control instruction i , and each corresponding instruction c i Differentiate into n different instructions.

[0016] Furthermore, in the light source module, when the light signal intensity I and the modulation frequency f are within the effective range, the encoding mode function M(I,f) of the light signal will correspond to each instruction c i Different instructions are divided into n sub-intervals, namely Among them, c1, c2, …, c n are different instructions in the control instruction set, I1, I2, ..., I n and f1,f2,…,f n are respectively the boundary values ​​of the n sub-intervals into which the value ranges of the optical signal intensity I and the modulation frequency f are divided.

[0017] Furthermore, the signal encoding unit includes: a central processing unit for receiving a control instruction and calculating a corresponding optical signal intensity I and a modulation frequency f;

[0018] The digital-to-analog converter is used to convert the calculated optical signal intensity I and modulation frequency f into an analog signal to drive the laser in the light source module.

[0019] Furthermore, the flight control execution module includes an attitude control unit, a speed control unit and a heading control unit, wherein:

[0020] An attitude control unit, used for adjusting the attitude of the UAV according to the calculated flight attitude adjustment amount θ;

[0021] A speed control unit, used for adjusting the speed of the drone according to the calculated speed control amount v;

[0022] The heading control unit is used to adjust the heading of the UAV according to the calculated heading change φ.

[0023] Furthermore, a communication verification module is provided between the ground control end and the UAV end. The communication verification module is used to add verification information to the encoded optical signal at the ground control end, and is used to verify the decoded control instruction at the UAV end. When the verification fails, the control instruction is discarded and a retransmission request is sent to the ground control end. After receiving the retransmission request, the ground control end resends the optical signal with the verification information until it is ensured that the UAV always receives accurate control instructions.

[0024] Furthermore, the ground control end also includes a human-computer interaction interface, which has a touch screen and physical buttons. The operator intuitively inputs control commands and views the real-time status information of the drone through the touch screen. The physical buttons are used for one-key operations in emergency situations, including emergency stop, return, and mission. Wireless data is transmitted between the human-computer interaction interface and the signal encoding unit, so that the signal encoding unit can receive and encode human-computer interaction control commands in real time.

[0025] On the other hand, a method for controlling a drone is provided, and the specific steps of the method are:

[0026] S1. Input control instructions through the human-machine interaction interface of the ground control terminal, and the human-machine interaction interface transmits the control instructions to the signal encoding unit;

[0027] S2. The central processor in the signal encoding unit calculates the corresponding optical signal intensity and modulation frequency according to the received control instruction, and the digital-to-analog converter converts the calculated digital signal into an analog signal to drive the laser in the light source module to generate an optical signal with corresponding intensity and frequency modulation;

[0028] S3, the beam directional transmission module transmits the encoded optical signal in a direction to the airspace where the drone is located, ensuring that the optical signal can cover the receiving range of the photoacoustic receiving module of the drone;

[0029] S4, after receiving the optical signal, the photoacoustic receiving module on the drone side generates a corresponding sound wave signal based on the photoacoustic effect;

[0030] S5, after receiving the sound wave signal, the signal decoding and processing unit extracts its characteristic value, decodes the sound wave signal into a control instruction, and calculates the flight attitude adjustment amount, speed control amount and heading change amount respectively;

[0031] S6, the attitude control unit in the flight control execution module adjusts the attitude of the UAV according to the calculated flight attitude adjustment amount, the speed control unit adjusts the speed of the UAV according to the speed control amount, and the heading control unit adjusts the heading of the UAV according to the heading change amount;

[0032] S7. The communication verification module between the ground control end and the UAV end continues to work. The ground control end adds verification information to the optical signal after encoding it and transmits it together. The UAV end performs verification after decoding the control command.

[0033] Compared with the prior art, the control system and method of the UAV has the following beneficial effects:

[0034] 1. This system detects the emitted sound waves through the photoacoustic effect, infers the characteristic information of the intensity and frequency of the optical signal, and uses the optical signal as an information carrier to realize remote control of the UAV through photoacoustic conversion and acoustic signal processing. At the same time, the introduction of photoacoustic conversion and encoding and decoding mechanism realizes high-precision and long-distance transmission of UAV control commands, thereby enhancing the receiving end's ability to capture weak signals, allowing the system to flexibly respond to signal attenuation problems under different lighting conditions and flight environments, ensuring that control commands can be accurately transmitted and executed.

[0035] 2. This system achieves high-precision control command transmission by precisely controlling the intensity and modulation frequency of the light source. The signal decoding and processing unit on the drone side can accurately parse the control commands and calculate precise flight control parameters based on the commands to ensure that the flight attitude and motion state of the drone are precisely controlled. In addition, real-time detection and feedback are performed during the decoding process to continuously monitor the flight status and position information of the drone. Once deviations and abnormal conditions are found, they can be corrected immediately by adjusting the control commands, thereby effectively avoiding flight accidents and ensuring that the drone performs its mission safely and stably.

[0036] Other advantages, objectives and features of the present invention will be set forth in part in the following description and, in part, will be apparent to those skilled in the art based on an examination of the following or may be taught from the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0038] Figure 1 The present invention is an operation flow chart of a control system of a UAV; Figure 2 This is a unit composition diagram of a flight control module in a control system of a UAV; Figure 3 This is a structural diagram of a signal coding unit in a UAV control system. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] Embodiment 1

[0043] This embodiment describes in detail the application of a single UAV control system based on the photoacoustic effect in a long-distance stable control scenario. By designing the collaborative work of various modules on the ground control end and the UAV end, and utilizing a specific encoding and decoding mechanism and precise optical signal modulation, stable control of the UAV over long distances is achieved, overcoming the limitations of traditional control methods and effectively improving control accuracy and reliability.

[0044] In the specific implementation, first, the light source module of the ground control end adopts a high-power laser, and the adjustable range of its optical signal intensity I is set to I min To I max , the range of modulation frequency f is f min to f maxTo ensure that all control instruction coding modes can be covered, different control instruction coding modes are corresponding to different combinations of I and f through the M(I,f) function. The coding mode function M(I,f) of the optical signal is defined as: where w i is the weight of the i-th control instruction, I min is the minimum optical signal intensity, I max is the maximum light signal intensity, f min is the minimum modulation frequency, f max is the maximum modulation frequency, c i is the i-th control instruction, I0 is the basic intensity value, f0 is the basic frequency value, k1 is the intensity adjustment coefficient of the instruction, k2 is the frequency adjustment coefficient of the instruction, δ(x) is the instruction judgment function, which is used to indicate that when x=0, the value is 1, otherwise it is 0. Through this coding mode function M(I,f), different combinations of optical signal intensity I and modulation frequency f are mapped to specific control instructions c i , when the optical signal intensity I and modulation frequency f exceed the range (I min , I max ) and (f min , f max ), the coding mode function M(I,f) returns 0, indicating invalid coding; when the optical signal intensity I and the modulation frequency f are within the valid range, the coding mode function M(I,f) maps I and f to a specific control instruction c through the instruction judgment function δ i Specifically, when (I-I0) / k1 and (f-f0) / k2 are both equal to one of the control instructions c i When , the encoding mode function returns the weight w of the control instruction i , and each corresponding instruction c i Differentiate into n different instructions.

[0045] Then, the signal encoding unit is composed of a central processing unit and a digital-to-analog converter. The central processing unit is responsible for receiving control instructions from the human-computer interaction interface. The control instruction set is defined as C = {c1, c2, c3, ..., c n}, where c i represents the ith control command, such as take-off, landing, hovering, forward flight, backward flight, left turn, right turn, ascent, descent, etc. The central processor receives the control command c i , using the signal coding formula I = I0 + k1 × c i and f = f0 + k2 × c iThe corresponding optical signal intensity I and modulation frequency f are calculated, where I0, f0, k1 and k2 are the basic intensity, frequency value and corresponding adjustment coefficient. After the calculation is completed, the digital-to-analog converter converts the digital signal calculated by the central processor into an analog signal to drive the laser in the light source module to generate an optical signal with corresponding intensity and frequency modulation. The light beam directional transmission module can accurately transmit the encoded optical signal to the airspace where the drone is located, and the optical signal can cover the receiving range of the photoacoustic receiving module of the drone. According to the real-time position and flight direction of the drone, the transmission angle is dynamically adjusted to ensure the effective transmission of the optical signal.

[0046] After receiving the light signal emitted by the ground control end, the photoacoustic receiving module generates a corresponding sound wave signal based on the photoacoustic effect. The module can efficiently convert the light signal into a sound wave signal, accurately capture the light signal and generate a stable sound wave signal, and transmit it to the signal decoding and processing unit in real time. After receiving the sound wave signal generated by the photoacoustic receiving module, the signal decoding and processing unit extracts its eigenvalue S and uses the decoding formula Decode the sound wave signal into the control command c′ i , where S0 is the reference value of the sound wave signal, k3 is the decoding coefficient, and the control instruction c′ obtained by decoding i The signal decoding and processing unit calculates the flight control parameters. The calculation formula of the flight attitude adjustment amount θ is θ=k4×c′ i , where k4 is the attitude adjustment coefficient; the speed control amount v is calculated as v = v0 + k5 × c' i , where v0 is the basic speed value, k5 is the speed adjustment coefficient; the calculation formula for the heading change φ is φ=k6×c′ i , where k6 is the heading adjustment coefficient. These coefficients are experimentally set according to the flight performance and control requirements of the UAV. During the experiment, each coefficient can be adjusted, the response of the UAV can be recorded, and then the data can be analyzed to find the optimal coefficient setting. Then, the flight control execution module drives the UAV's actuator according to the flight control parameters calculated by the signal decoding and processing unit. The flight control execution module includes an attitude control unit, a speed control unit and a heading control unit. The attitude control unit adjusts the attitude of the UAV according to the calculated flight attitude adjustment amount θ, and changes the attitude parameters of the UAV such as the pitch angle and roll angle by controlling the UAV's motor, steering gear and other actuators to ensure that the UAV maintains a stable flight attitude in the air; the speed control unit adjusts the speed of the UAV according to the speed control amount v, and realizes the acceleration, deceleration or uniform speed flight of the UAV by adjusting the speed of the motor, etc., to meet the speed requirements of different flight missions; the heading control unit adjusts the heading of the UAV according to the heading change amount φ, accurately controls the flight direction of the UAV, and makes it fly accurately according to the operator's instructions.

[0047] Finally, during the flight control process, the communication verification module set between the ground control end and the UAV end works continuously during the entire control process. The ground control end adds verification information after encoding the optical signal and transmits it together. After decoding the control command, the UAV end verifies the received command. If the verification result shows that the command is transmitted correctly, the UAV continues to execute the command; if the verification fails, the control command is discarded and a retransmission request is sent to the ground control end. After receiving the retransmission request, the ground control end re-executes the signal encoding and optical signal transmission operations, and sends the optical signal with verification information again until the UAV end successfully receives the accurate control command. This command retransmission mechanism effectively guarantees the accuracy and reliability of the control command during long-distance transmission, avoids the incorrect execution of commands due to signal interference or attenuation, and ensures the safety of the UAV and the stability of mission execution.

[0048] In summary, in this embodiment, the UAV control system based on the photoacoustic effect successfully realizes the stable control of the UAV at a long distance. From the command input and optical signal coding transmission of the ground control end to the reception, decoding processing and flight control execution of the UAV end, each link works closely together, and uses precise optical signal modulation and coding and decoding mechanisms to effectively overcome the signal attenuation and interference problems caused by long-distance transmission. At the same time, the introduction of the communication verification module further improves the reliability of the control command transmission, ensuring that the UAV can accurately execute the operator's instructions and maintain a stable flight attitude and motion state during long-distance flight missions.

[0049] Embodiment 2

[0050] This embodiment focuses on the scenario of multi-UAV collaborative operation, and explains how the UAV control system based on the photoacoustic effect can effectively solve the signal conflict problem caused by limited spectrum resources. Through a unique coding mode, precise optical signal modulation and an efficient collaborative mechanism, multiple UAVs can work together stably and orderly in a complex environment, thereby improving overall operation efficiency and reliability.

[0051] The light source module of the ground control end adopts a high-power laser, and its optical signal intensity I can be min To I max The modulation frequency f is adjusted within the range of f min to f max Interval, different combinations of I and f correspond to different control instruction encoding modes through the M(I,f) function, and the encoding mode function M(I,f) of the optical signal is: Among them, w i is the weight of the i-th control instruction, I min is the minimum optical signal intensity, I max is the maximum light signal intensity, fmin is the minimum modulation frequency, f max is the maximum modulation frequency, c i is the i-th control instruction, I0 is the basic intensity value, f0 is the basic frequency value, k1 is the intensity adjustment coefficient of the instruction, k2 is the frequency adjustment coefficient of the instruction, δ(x is the instruction judgment function, which is used to indicate that when x=0, the value is 1, otherwise it is 0. Through this coding mode function M(I,f), different combinations of optical signal intensity I and modulation frequency f are mapped to specific control instructions c i Specifically, when (I-I0) / k1 and (f-f0) / k2 are both equal to one of the control instructions c i When , the encoding mode function returns the weight w of the control instruction i , and each corresponding instruction c i Different instructions are divided into n sub-intervals, namely Among them, c1, c2, …, c n are different instructions in the control instruction set, I1, I2, ..., I n and f1,f2,…,f n are the boundary values ​​of n sub-intervals into which the value range of the optical signal intensity I and the modulation frequency f is divided. The central processor in the signal encoding unit is ready to receive collaborative task instructions. The digital-to-analog converter is on standby and can convert the calculated optical signal parameters into analog signals to drive the laser at any time. The human-computer interaction interface displays the multi-UAV collaborative operation mode options, where the operator can set the task parameters, such as UAV grouping, task objectives of each group, etc. The optoacoustic receiving module, signal decoding and processing unit and flight control execution module of each UAV are in normal working condition. The optoacoustic receiving module can effectively convert the received optical signal into an acoustic wave signal. In the initialization stage, the ground control end groups the UAVs through specifically coded optical signals, that is, sets one of the optical signal intensities I g and the modulation frequency f g When the drone receives the signal, the signal decoding and processing unit uses the decoding formula (Where S is the characteristic value of the received sound wave signal, S0 is the reference value, and k3 is the decoding coefficient) parse out the grouping instruction c' g , according to c g The drone determines the group to which it belongs and prepares for subsequent collaborative operations. The operator performs tasks based on the requirements of multi-drone collaborative operations, such as area search, target tracking, and material distribution.

[0052] The task allocation strategy is formulated on the human-computer interaction interface of the ground control end, and multiple drones are divided into several groups. Each group undertakes specific subtasks, and the tasks between the groups cooperate with each other. In the regional search task, the drones are responsible for the search work in different areas. At the same time, a data aggregation group is set up to receive the information of each search group and conduct integrated analysis. For each group of drones, the signal encoding unit of the ground control end calculates the corresponding optical signal intensity I and modulation frequency f according to the task allocation, and according to the control instruction set C = {c1, c2, c3, …, c n} in the group task instruction c i , using the formula I = I0 + k1 × c i and f = f0 + k2 × c i After the central processor calculates the optical signal parameters, the digital-to-analog converter converts it into an analog signal, driving the laser in the light source module to generate an optical signal with corresponding intensity and frequency modulation. The beam directional transmission module transmits the encoded optical signal in a direction to the airspace where the corresponding group of drones is located to ensure that each drone can receive accurate mission instruction optical signals.

[0053] After the photoacoustic receiving module of each group of drones receives the light signal emitted by the ground control end, it generates an acoustic wave signal based on the photoacoustic effect. The signal decoding and processing unit extracts the characteristic value S of the acoustic wave signal and uses the decoding formula Decode the sound wave signal into the control command c′ i If the decoded command is a flight control command, such as flight direction adjustment, speed change, etc., according to the formula θ=k4×c′ i (posture adjustment amount θ), v = v0 + k5 × c′ i (speed control amount v), φ = k6 × c' i (heading change φ) calculates the flight control parameters, where k4, k5, and k6 are the corresponding adjustment coefficients. The attitude control unit in the flight control execution module adjusts the attitude of the drone according to the calculated flight attitude adjustment θ, the speed control unit adjusts the speed according to the speed control amount v, and the heading control unit adjusts the heading according to the heading change φ, so that the drones can fly in coordination according to the assigned tasks. That is, in the search mission, each search team drone flies along the predetermined route, maintains a certain spacing and search mode, and at the same time transmits its own position and search information to the ground control end or the designated data summary drone in real time through optical signal encoding. After receiving the information from each group, the data summary drone conducts integrated analysis, and adjusts the mission parameters of each group drone according to the overall mission requirements, and sends instructions through the ground control end again to realize dynamic collaborative operations between multiple drones.

[0054] During the flight control process of each group of drones, the communication verification module between the ground control end and each drone continues to work. The ground control end adds verification information after encoding the optical signal and transmits it together. After decoding the control command, the drone end verifies the received command. If the verification fails, the drone end discards the control command and sends a retransmission request to the ground control end. After receiving the request, the ground control end resends the optical signal with verification information to ensure that the drone always receives accurate control commands. Due to the use of optical signal transmission with photoacoustic effect, different groups of drones can communicate through different combinations of optical signal strength and modulation frequency, effectively avoiding the signal conflict problem caused by limited radio wave spectrum resources. At the same time, during the dynamic collaborative operation process, if there are signs of signal interference (such as verification errors), the ground control end can adjust the optical signal parameters in time and reallocate the task instruction coding to ensure the stability and reliability of multi-drone collaborative operation. The human-computer interaction interface of the ground control end displays the flight status information of each drone in real time, including position, attitude, speed, etc. The operator can intuitively monitor the execution of the entire multi-drone collaborative operation task. The signal decoding and processing unit on each drone side continuously monitors its own flight status, and transmits key information (encountering obstacles, low battery, etc.) back to the ground control side after encoding the optical signal, so that the operator can make timely decisions. According to the task execution and environmental changes, the operator can dynamically adjust the task allocation and drone flight parameters on the ground control side. The ground control side recalculates the optical signal strength and modulation frequency according to the adjusted task instructions, and sends the encoded optical signal to the corresponding drone through the beam directional transmission module. After receiving the new instructions, the drone side adjusts the flight status and continues to collaborate on the task to ensure that the entire task can be completed efficiently and safely.

[0055] To sum up, in the multi-UAV collaborative operation scenario, the UAV control system based on the photoacoustic effect in this embodiment realizes the stable collaborative work of multiple UAVs in an environment with limited spectrum resources. From group recognition at system initialization to task allocation, collaborative flight control, communication verification and dynamic adjustment, each link works closely together to ensure efficient collaboration between UAVs and accurate execution of tasks.

[0056] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A control system for an unmanned aerial vehicle, characterized in that: The control system includes a ground control end and a UAV end. The ground control end includes: a light source module, a signal encoding unit and a beam directional emission module. The UAV end includes: a photoacoustic receiving module, a signal decoding and processing unit and a flight control execution module. The light source module can generate light signals of different intensities and modulation frequencies. The light source module uses a high-power laser to generate a specific light signal mode for controlling the drone, that is, the light signal intensity is set to I, the modulation frequency is f, and the coding mode function of the light signal is M(I,f), where the value range of I is I min To I max , the value range of f is f min to f max , different combinations of I and f correspond to different control instruction encoding modes through the M(I,f) function; The signal encoding unit is connected to the light source module and is used to convert the control instructions into corresponding light signal intensity and frequency modulation information, so that the drone end can accurately parse the control instructions, that is, define the control instruction set as C = {c1, c2, c3, ..., c n }, where c i It represents the i-th control instruction, and its signal encoding is I=I0+k1×c i , f=f0+k2×c i , where I0 and f0 are the basic intensity and frequency values, k1 and k2 are the intensity and frequency adjustment coefficients of the command respectively. The control command c is encoded through this signal i Converted into corresponding optical signal intensity I and frequency f to adjust control information: The beam directional transmission module is used to transmit the encoded optical signal in a direction to the airspace where the drone is located, so that the optical signal covers the receiving range of the drone; The photoacoustic receiving module is used to receive the light signal emitted by the ground control end, and after receiving the light signal, generate a corresponding sound wave signal based on the photoacoustic effect; The signal decoding and processing unit is connected to the photoacoustic receiving module, and is responsible for decoding the sound wave signal generated by the photoacoustic receiving module, restoring it to the original control command information, and calculating the flight control parameters of the UAV according to the command. The control parameters include the flight attitude adjustment amount, the speed control amount and the heading change amount. The characteristic value of the received sound wave signal is S, and it is decoded into Where S0 is the reference value of the sound wave signal, k3 is the decoding coefficient, that is, the sound wave signal S is decoded and restored to the control instruction c′ i , calculate the flight control parameters according to the control instructions, that is, calculate the flight attitude adjustment amount θ as: θ = k4 × c′ i , where k4 is the attitude adjustment coefficient, and the speed control amount v is: v = v0 + k5 × c' i , where v0 is the basic speed value, k5 is the speed adjustment coefficient, and the heading change φ is: φ=k6×c′ i , where k6 is the heading adjustment coefficient; The flight control execution module is used to drive the actuator of the UAV according to the control parameters calculated by the signal decoding and processing unit, so as to realize the precise control of the flight attitude and motion state of the UAV.

2. The control system of an unmanned aerial vehicle according to claim 1, characterized in that: The coding mode function M(I,f) of the light signal in the light source module is: Among them, w i is the weight of the i-th control instruction, I min is the minimum optical signal intensity, I max is the maximum light signal intensity, f min is the minimum modulation frequency, f max is the maximum modulation frequency, c i is the i-th control instruction, I0 is the basic intensity value, f0 is the basic frequency value, k1 is the intensity adjustment coefficient of the instruction, k2 is the frequency adjustment coefficient of the instruction, δ(x) is the instruction judgment function, which is used to indicate that when x=0, the value is 1, otherwise it is 0. Through this coding mode function M(I,f), different combinations of optical signal intensity I and modulation frequency f are mapped to specific control instructions c i ,Right now: When the optical signal intensity I and modulation frequency f exceed the range (I min , I max ) and (f min , f max ), the encoding mode function M(I,f) returns 0, indicating invalid encoding; When the optical signal intensity I and the modulation frequency f are within the valid range, the coding mode function M(I, f ) Map I and f to specific control instructions c through the instruction judgment function δ i Specifically, when (I-I0) / k1 and (ff 0) / k2 is also equal to one of the control commands c i When , the encoding mode function returns the weight w of the control instruction i , and each corresponding instruction c i Differentiate into n different instructions.

3. The control system of an unmanned aerial vehicle according to claim 2, characterized in that: In the light source module, when the light signal intensity I and the modulation frequency f are within the effective range, the encoding mode function M(I,f) of the light signal will correspond to each instruction c i Different instructions are divided into n sub-intervals, namely Among them, c1, c2, …, c n are different instructions in the control instruction set, I1, I2, ..., I n and f1,f2,…,f n are respectively the boundary values ​​of the n sub-intervals into which the value ranges of the optical signal intensity I and the modulation frequency f are divided.

4. The control system of an unmanned aerial vehicle according to claim 1, characterized in that: The signal encoding unit comprises: A central processing unit, used to receive control instructions and calculate the corresponding optical signal intensity I and modulation frequency f; The digital-to-analog converter is used to convert the calculated optical signal intensity I and modulation frequency f into an analog signal to drive the laser in the light source module.

5. The control system of a drone according to claim 1, characterized in that: The flight control execution module includes an attitude control unit, a speed control unit and a heading control unit, wherein: An attitude control unit, used for adjusting the attitude of the UAV according to the calculated flight attitude adjustment amount θ; A speed control unit, used for adjusting the speed of the drone according to the calculated speed control amount v; A heading control unit is used to change the heading according to the calculated Adjust the drone's heading.

6. The control system of an unmanned aerial vehicle according to claim 1, characterized in that: A communication verification module is provided between the ground control end and the UAV end. The communication verification module is used at the ground control end to add verification information to the encoded optical signal, and is used at the UAV end to verify the decoded control instruction. When the verification fails, the control instruction is discarded and a retransmission request is sent to the ground control end. After receiving the retransmission request, the ground control end resends the optical signal with the verification information until it is ensured that the UAV always receives accurate control instructions.

7. The control system of a drone according to claim 1, characterized in that: The ground control end also includes a human-computer interaction interface, which has a touch screen and physical buttons. The operator can intuitively input control instructions and view the real-time status information of the drone through the touch screen. The physical buttons are used for one-key operations in emergency situations, including emergency stop and return. Wireless data is transmitted between the human-computer interaction interface and the signal encoding unit, so that the signal encoding unit can receive and encode human-computer interaction control instructions in real time.

8. A method for controlling an unmanned aerial vehicle, applicable to a control system for an unmanned aerial vehicle according to any one of claims 1 to 7, characterized in that: The specific steps of the control method are: S1. Input control instructions through the human-machine interaction interface of the ground control terminal, and the human-machine interaction interface transmits the control instructions to the signal encoding unit; S2. The central processor in the signal encoding unit calculates the corresponding optical signal intensity and modulation frequency according to the received control instruction, and the digital-to-analog converter converts the calculated digital signal into an analog signal to drive the laser in the light source module to generate an optical signal with corresponding intensity and frequency modulation; S3, the beam directional transmission module transmits the encoded optical signal in a direction to the airspace where the drone is located, ensuring that the optical signal can cover the receiving range of the photoacoustic receiving module of the drone; S4, after receiving the optical signal, the photoacoustic receiving module on the drone side generates a corresponding sound wave signal based on the photoacoustic effect; S5, after receiving the sound wave signal, the signal decoding and processing unit extracts its characteristic value, decodes the sound wave signal into a control instruction, and calculates the flight attitude adjustment amount, speed control amount and heading change amount respectively; S6, the attitude control unit in the flight control execution module adjusts the attitude of the UAV according to the calculated flight attitude adjustment amount, the speed control unit adjusts the speed of the UAV according to the speed control amount, and the heading control unit adjusts the heading of the UAV according to the heading change amount; S7. The communication verification module between the ground control end and the UAV end continues to work. The ground control end adds verification information to the optical signal after encoding it and transmits it together. The UAV end performs verification after decoding the control command.

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