Quadrotor control system based on visual SLAM

Abstract

The invention relates to the field of aircraft control technology, in particular to a quadcopter control system based on visual SLAM; the control system comprises: an environment perception module, a server, and a flight control module; a comprehensive analysis is performed on the wind speed and air pressure of the environment in which the quadcopter is located to measure the influence of the wind speed and air pressure on the quadcopter, and a proofreading control instruction is generated accordingly; when the proofreading control instruction is received, the flight posture and rotor speed are adjusted according to the environmental state so that the quadcopter can adapt to the flight environment under different wind speed and air pressure conditions, and then the environment is repeatedly perceived and repeatedly adjusted according to the adjustment demand index, so that the quadcopter can make adjustments to the environmental changes more timely and maintain a stable flight state; more refined flight adjustments, enhanced environmental adaptability, faster adjustment response speed and a complete automated flight adjustment process are achieved, the complexity of operation can be reduced, and the intelligence and autonomy of the aircraft are improved.

Description

Technical Field

[0001] The present invention relates to the field of aircraft control technology, in particular to a quadrotor aircraft control system based on visual SLAM. Background Art

[0002] A quadrotor is a multi-purpose aerial platform that can carry various sensors, such as infrared cameras, thermal imagers, and multispectral sensors, for agricultural monitoring, forest fires, environmental monitoring, geological exploration, and other fields. It can also be used for short-distance cargo transportation, such as express delivery and emergency medical supplies transportation. In short, quadrotors have the advantages of flexibility, low cost, and easy operation, so they have a wide range of uses and application prospects in various fields. It can be seen that the control of quadrotors is very necessary to ensure that they can perform various tasks safely and efficiently.

[0003] Although modern quadcopters are equipped with autopilot systems, human intervention is still required in certain circumstances. For example, in complex and unstable environments, quadcopters are more sensitive to the external environment and can be easily affected, causing unstable flight. Human intervention is required, resulting in the quadcopter control process being not intelligent enough. At the same time, human intervention is highly subjective, which can easily lead to improper control and increase flight safety risks. Summary of the invention

[0004] The purpose of the present invention is to provide a quadrotor control system based on visual SLAM to solve the problems mentioned in the above background technology.

[0005] The purpose of the present invention can be achieved by the following technical solutions: A quadrotor control system based on visual SLAM, comprising: a server, an environment perception module and a flight control module;

[0006] The server communicates with the visual sensor to obtain visual information of the environment, and uses the SLAM algorithm to process the visual information to build an environmental map in real time and locate the position of the quadcopter in real time; thereby, a real-time positioning map of the quadcopter can be obtained, wherein the positioning map includes the environment in which the quadcopter is located, the position of the quadcopter, and the flight posture of the quadcopter; the server is also used to communicate with the wind speed sensor, the pressure sensor, and the temperature sensor to obtain environmental information, wherein the environmental information includes wind speed and air pressure;

[0007] The environment perception module performs real-time fluctuation analysis on the environment in which the quadcopter is located based on the environmental information to determine the degree of its impact on the flight of the quadcopter, and generates a calibration control command based on the environmental information and sends it to the flight control module;

[0008] When the flight control module receives the calibration control command, it performs a decomposition analysis based on the environmental state of the quadcopter to obtain the control parameters, and adjusts the flight of the quadcopter according to the adjustment parameters; specifically:

[0009] Step 1: Retrieve the wind speed vector corresponding to the current moment and decompose it along the rotor coordinate axis to obtain the scalars about the four rotor axes, which are recorded as rotor scalars. and A, B, C, and D are the numbers of the four rotor motors respectively; retrieve the wind speed vector direction, and based on this, the resistance posture of the quadrotor is generated, and its resistance posture is related to the wind speed vector , where i = 1, 2, 3 ... I, I is a positive integer, I represents the total number of acquisition moments, and i represents the sequence number of any one of the acquisition moments; obtain the inclination angle of the current quadrotor rotation plane and the inclination angle of the rotation plane of the resistance posture, and calculate the difference between the two to obtain the inclination angle adjustment value;

[0010] Step 2: Retrieve the air pressure at each detection point of the quadrotor at the current moment, and divide each detection point on the surface of the quadrotor fuselage into corresponding rotor motors according to their positions, thereby obtaining the air pressure corresponding to each rotor motor, and calculating the average value to obtain the corresponding air pressure of each rotor motor, which is recorded as A Qi , B Qi , C Qi and B Qi ; Using the set formula Calculate and obtain the adjusted speed R of each rotor motor A , R B , R C and R D , where d1, d2, d3, d4, d5, d6, d7, and d8 are the set proportional coefficients, A , δ B , δ C , δ D are the speed conversion coefficients of rotor motor A, rotor motor B, rotor motor C and rotor motor D, respectively; HA, HB, HC and HD are the standard air pressures at the standard speeds of standard rotor motors A, B, C and D, respectively;

[0011] The tilt angle adjustment value and the rotation speed of each rotor motor are used as adjustment parameters, and the flight of the quadrotor aircraft is adjusted according to the adjustment parameters;

[0012] Step 3: After each adjustment, send an environmental repetition perception command to the environmental perception module to obtain an adjustment demand index. When the adjustment demand index is greater than the set adjustment threshold, repeat steps 1 to 2 to perform flight adjustments on the quadcopter until the demand index is less than or equal to the set adjustment threshold, then maintain the current flight state.

[0013] Preferably, the specific process of performing real-time fluctuation analysis on the environment in which the quadrotor is located based on environmental information is as follows:

[0014] 201: retrieve the wind speed corresponding to each collection time and record it as J is a positive integer, J represents the total number of surface detection points of the quadrotor, and j represents the serial number of any one of the surface detection points of the quadrotor. The three-dimensional coordinates are established with the quadrotor as the origin, and the wind speed corresponding to each detection point is decomposed and reorganized to obtain the wind speed scalar B. X i. B Y i and B Z i, the wind speed direction is adjusted according to B X i. B Y i and B Z i draws the wind speed vector in three-dimensional space and records it as And conduct in-depth analysis to obtain the wind speed change index;

[0015] 202: Retrieving the air pressure at each detection point on the surface of the quadrotor aircraft at each collection time, and analyzing the air pressure uniformity on the surface of the quadrotor aircraft based on the air pressure uniformity to obtain the air pressure performance value corresponding to each collection time; and then performing trend analysis based on the air pressure performance value corresponding to each collection time to obtain the air pressure change index;

[0016] 203: Substitute the wind speed change index Sa and the air pressure change index Da into the set formula SD=a6×Sa+a7×Da to calculate the adjustment demand index SD, where a6 and a7 are set proportional coefficients respectively. When the adjustment demand index is greater than the set demand threshold, a proofreading control instruction is generated and sent to the control module.

[0017] Preferably, the specific process of decomposing and recombining the wind speed corresponding to each detection point is:

[0018] The origin is the quadrotor, the forward direction of the quadrotor is the horizontal axis, i.e., the X-axis; the vertically upward direction perpendicular to the origin is the positive vertical axis, i.e., the Z-axis; the vertical axis perpendicular to the horizontal and vertical axes is the Y-axis; thus, a three-dimensional coordinate system can be established; the wind speed at each detection point on the surface of the quadrotor is calculated. Decomposing in three-dimensional coordinates can obtain the decomposed wind speed V of each detection point X ij、VY ij and V Z ij; thus, the wind speed of each detection point in three-dimensional coordinates can be obtained; using the set formula Calculate the apparent wind speed scalar B X i. B Y i and B Z i; According to the apparent wind speed, the wind speed direction is adjusted according to B X i. B Y i and B Z iDraw in three-dimensional space to get the wind speed vector

[0019] Preferably, the specific process of in-depth analysis of the wind speed vector is as follows:

[0020] The apparent wind speed vector corresponding to each acquisition time is retrieved, and the angle between the apparent wind speed vectors corresponding to adjacent acquisition times is calculated and recorded as α, and the modulus difference of the apparent wind speed vectors corresponding to adjacent acquisition times is calculated by difference, and recorded as The angle α and the wind speed modulus difference Substitute the set formula Bh = lg (h1 × e α +h2×e β +1) to calculate the change scalar Bh of the wind speed vector corresponding to the adjacent acquisition moments, where h1 and h2 are the set proportional coefficients respectively;

[0021] Compare and analyze the change scalar with the set change interval to divide the change scalar into a primary change scalar, a secondary change scalar and a tertiary change scalar, and record the number of the primary change scalar, the secondary change scalar and the tertiary change scalar as the cumulative number of high wind speed changes, medium wind speed changes and low wind speed changes, and record them as S1, S2, S3 respectively; sum the primary change scalar, the secondary change scalar and the tertiary change scalar to obtain the primary change total value, the secondary change total value and the tertiary change total value, and record them as S4, S5, S6 respectively;

[0022] Substitute S1, S2, S3, S4, S5, S6 into the set formula The wind speed variation index is calculated, where a1, a2, and a3 are respectively set proportional coefficients, and a1>a2>a3>0.

[0023] Preferably, the specific process of analyzing the air pressure uniformity on the surface of the quadrotor aircraft is:

[0024] Compare and analyze the air pressure with the set air pressure range to divide the air pressure into primary, secondary and tertiary air pressures, count the number of primary, secondary and tertiary air pressures respectively, and record them as P1, P2 and P3 respectively; use the set formula The air pressure expression value Pa is calculated, where b1 and b2 are respectively set proportional coefficients, thereby obtaining the air pressure expression value Pai corresponding to each collection moment.

[0025] Preferably, the specific process of trend analysis of the air pressure performance value corresponding to the collection time is:

[0026] A graph of the change of the pressure expression value over time is drawn with time as the horizontal coordinate and the pressure expression value as the vertical coordinate; a tangent line is drawn at the pressure point, and a tangent expression is obtained by data fitting, and the pressure derivative corresponding to each pressure point is obtained by derivation of the tangent expression; the pressure derivatives greater than zero are summed to obtain the pressure influence single value increase, and the pressure derivatives less than zero are summed and the absolute value is taken to obtain the pressure single value decrease, and the number of pressure derivatives equal to zero is counted and recorded as the pressure stability value;

[0027] Substitute the pressure performance value Pai, the pressure impact value D1, the pressure deduction value D2 and the pressure stability value D3 into the set formula The pressure change index Da is calculated, where a4 and a5 are respectively set proportional coefficients.

[0028] Beneficial effects of the present invention:

[0029] 1. By analyzing the wind speed and air pressure of the environment in which the quadcopter is located, the wind speed change index Sa and the air pressure change index Da are obtained, and the two are comprehensively analyzed to measure their impact on the quadcopter, and the calibration control instructions are generated accordingly; it can monitor environmental changes in real time, which helps to timely discover the impact of environmental changes on the aircraft, take corresponding control measures in advance, and ensure the safe flight of the aircraft;

[0030] 2. By adjusting the flight posture and rotor speed according to the environmental conditions, the quadcopter can adapt to the flight environment under different wind speed and air pressure conditions. Then, by sending repeated environmental perception instructions and making repeated adjustments based on the adjustment demand index, the quadcopter can adjust to environmental changes more promptly and maintain a stable flight state. It achieves more refined flight adjustments, enhanced environmental adaptability, faster adjustment response speed and a complete automated flight adjustment process, which can reduce the complexity of operations and improve the intelligence and autonomy of the aircraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention will be further described below in conjunction with the accompanying drawings.

[0032] Figure 1 is a schematic diagram of system module connection of the present invention;

[0033] Figure 2 It is a schematic diagram of the rotor coordinate axis of the present invention. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. 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.

[0035] See also Figure 1 As shown, the present invention is a quadrotor control system based on visual SLAM, comprising: an environment perception module 101, a server 102 and a flight control module 103;

[0036] The server 102 communicates with the visual sensor to obtain visual information of the environment, and uses the SLAM algorithm to process the visual information to build an environmental map in real time and locate the position of the quadcopter in real time; thereby, a real-time positioning map of the quadcopter can be obtained, wherein the positioning map includes the environment in which the quadcopter is located, the position of the quadcopter, and the flight posture of the quadcopter; the server 102 is also used to communicate with the wind speed sensor, the pressure sensor, and the temperature sensor to obtain environmental information, wherein the environmental information includes wind speed and air pressure; it should be noted that a number of detection points are set on the surface of the quadcopter, and each detection point is equipped with a wind speed sensor and an air pressure sensor, so as to detect the wind speed and air pressure at various locations on the surface of the quadcopter at the same time;

[0037] The environment perception module 101 performs fluctuation analysis on the perceived environment information to determine the impact of the environment on the stable flight of the quadrotor aircraft, specifically:

[0038] Retrieve the wind speed corresponding to each collection time and record it as Wind speed is a vector, which refers to the wind speed with wind direction; i = 1, 2, 3 ... I, I is a positive integer, I represents the total number of collection moments, i represents the serial number of any collection moment; j = 1, 2, 3 ... J, J is a positive integer, J represents the total number of surface detection points of the quadrotor, j represents the serial number of any one of the surface detection points of the quadrotor; the quadrotor is taken as the origin, the forward direction of the quadrotor is the horizontal axis (ie, the X-axis), and the vertically upward direction perpendicular to the origin is the positive direction of the vertical axis (ie, the Z-axis) (the direction from the ground to the sky), and the vertical axis perpendicular to the horizontal axis and vertical is the vertical axis (ie, the Y-axis, it should be noted that the plane formed by the horizontal axis and the vertical axis is a horizontal plane parallel to the ground); thus, three-dimensional coordinates can be established; the wind speed of each detection point on the surface of the quadrotor is Decomposing in three-dimensional coordinates can obtain the decomposed wind speed of each detection point (the decomposed wind speed is a scalar without direction) V X ij、V Y ij and V Z ij; thus, the wind speed of each detection point in three-dimensional coordinates can be obtained; using the set formula Calculate the apparent wind speed scalar B X i. B Y i and B Z i; The apparent wind speed represents the comprehensive performance of the quadcopter in three-dimensional space affected by wind speed; the wind speed direction is calculated according to the apparent wind speed. X i. B Y i and B Z i draws the wind speed vector in three-dimensional space and records it as The angle between the apparent wind speed vectors corresponding to adjacent acquisition moments is calculated as α, and the modulus difference of the apparent wind speed vectors corresponding to adjacent acquisition moments is calculated by difference calculation to obtain the wind speed modulus difference, which is recorded as Using the set formula Bh = lg (h1 × e α +h2×e β +1) is used to calculate the change scalar Bh of the wind speed vector corresponding to the adjacent acquisition moments, where h1 and h2 are respectively the set proportional coefficients; the change scalar is compared and analyzed with the set change interval. When the change scalar is greater than the maximum value in the set change interval, it means that the wind speed vector corresponding to the adjacent acquisition moments has undergone a large change. The change scalar is recorded as a first-level change scalar, and a high wind speed change is accumulated once; when the change scalar is within the set change interval, the change scalar is recorded as a second-level change scalar, and a moderate wind speed change is accumulated once; when the change scalar is less than the minimum value in the set change interval, the change scalar is recorded as a third-level change scalar, and a low wind speed change is accumulated once; the cumulative number of high wind speed changes, moderate wind speed changes and low wind speed changes are counted respectively, and they are recorded as S1, S2, and S3 respectively; the first-level change scalar, the second-level change scalar and the third-level change scalar are summed up to obtain the first-level change total value, the second-level change total value and the third-level change total value, and they are recorded as S4, S5, and S6 respectively; using the set formula The wind speed variation index is calculated, where a1, a2, and a3 are respectively set proportional coefficients, and a1>a2>a3>0;

[0039] The air pressure at each detection point on the surface of the quadrotor aircraft at each acquisition moment is retrieved and recorded as Qij; the air pressure is compared and analyzed with the set air pressure range. When the air pressure is greater than the maximum value in the set air pressure range, it means that the other air pressures at the detection point are relatively large, and the air pressure is recorded as the first-level air pressure; when the air pressure is within the set air pressure range, it means that the air pressure is within the normal range, and the air pressure is recorded as the second-level air pressure; when the air pressure is less than the minimum value in the set air pressure range, the air pressure is recorded as the third-level air pressure; the number of first-level air pressure, second-level air pressure and third-level air pressure are counted respectively, and they are recorded as P1, P2, and P3 respectively; using the set formula The air pressure performance value Pa is calculated, where b1 and b2 are respectively the set proportional coefficients, and the air pressure performance value Pai corresponding to each acquisition time can be obtained; from the formula, it can be seen that when the difference in air pressure at each detection point on the surface of the quadrotor aircraft is greater (the more uneven the air pressure distribution on the surface of the quadrotor aircraft is), the greater the air pressure, which means that the quadrotor aircraft is more affected by the air pressure, and the greater the air pressure performance value;

[0040] A two-dimensional rectangular coordinate system is constructed with time as the horizontal coordinate and the pressure expression value Pai as the vertical coordinate. The pressure expression value Pai is input into the coordinate axis according to its corresponding collection time, and the position of the pressure expression value Pai in the coordinate axis is recorded as the pressure point. A smooth curve is used to connect the pressure points in sequence to obtain a curve of the pressure expression value Pai changing with time. A tangent line is drawn at the pressure point, and the tangent expression is obtained by data fitting. The tangent expression is derived to obtain the pressure derivative corresponding to each pressure point. When the pressure derivative is greater than zero, it indicates that the pressure at the pressure point is The value shows an upward trend, indicating that the quadrotor aircraft at this moment is affected by the air pressure and shows a continuous upward trend; when the air pressure derivative is less than zero, it means that the air pressure performance value at the air pressure point shows a downward trend, indicating that the quadrotor aircraft at this moment is affected by the air pressure and shows a continuous downward trend; the air pressure derivatives greater than zero are summed up to obtain the pressure influence single value increase, recorded as D1, and the air pressure derivatives less than zero are summed up and taken as the absolute value to obtain the pressure single value decrease, recorded as D2, and the number of air pressure derivatives equal to zero is counted and recorded as the air pressure stability value, recorded as D3; using the set formula The pressure change index Da is calculated, where a4 and a5 are respectively the set proportional coefficients;

[0041] The wind speed change index Sa and the air pressure change index Da are calculated by the set formula SD=a6×Sa+a7×Da to obtain the adjustment demand index SD, wherein a6 and a7 are set proportional coefficients respectively; when the adjustment demand index is greater than the set demand threshold, it means that the risk of the quadcopter having a difference between its flight posture and the prepared flight posture due to the influence of environmental factors is greater, and the quadcopter needs to be proofread and controlled so that the quadcopter can complete the flight mission according to the predetermined flight path and the prepared flight posture; then a proofreading control instruction is generated and sent to the control module;

[0042] By analyzing the wind speed and air pressure of the quadrotor's environment to obtain the wind speed change index Sa and the air pressure change index Da, and conducting a comprehensive analysis of the two to measure their impact on the quadrotor, proofreading control instructions are generated accordingly; it can monitor environmental changes in real time, help to promptly discover the impact of environmental changes on the aircraft, take corresponding control measures in advance, and ensure the safe flight of the aircraft.

[0043] When the flight control module 103 receives the calibration control instruction, it generates corresponding control parameters according to the state parameters, and performs flight control on the quadcopter according to the control parameters, so that the quadcopter can adapt to environmental changes and maintain stable flight; specifically:

[0044] Step 1: Retrieve the apparent wind speed vector corresponding to the current moment And follow it as Figure 2 The rotor coordinate axes shown in the figure can be decomposed to obtain the scalars about the four rotor axes, which are recorded as rotor scalars. and By showing the wind speed vector From the calculation process, we can know that the decomposition scalar in the vertical direction is B Z i; retrieve the wind speed vector direction, and based on this, the resistance posture of the quadrotor is generated, and its resistance posture is related to the wind speed vector in the opposite direction; obtaining the inclination angle of the current quadrotor rotation plane and the inclination angle of the rotation plane of the resistance posture, and calculating the difference between the two to obtain the inclination angle adjustment value. It should be noted that the inclination angle of the current quadrotor can be converted into the resistance posture after being adjusted by the inclination angle adjustment value;

[0045] Step 2: Retrieve the air pressure Qij at each detection point of the quadrotor at the current moment. It should be noted that the lower the air pressure, the smaller the lift that the quadrotor can generate, and it is necessary to increase the rotor electrode speed for compensation; divide each detection point on the surface of the quadrotor fuselage to the corresponding rotor motor according to its location, and the division is specifically manifested as the detection point is divided to the rotor motor closest to it; thereby, the air pressure corresponding to each rotor motor can be obtained, and the average value is calculated to obtain the corresponding attribution air pressure of each rotor motor, which is recorded as A Qi , B Qi , C Qi and B Qi ; Using the set formula Calculate and obtain the adjusted speed R of each rotor motor A , R B , R C and R D , where d1, d2, d3, d4, d5, d6, d7, and d8 are the set proportional coefficients, A , δ B , δ C , δ D are the speed conversion coefficients of rotor motor A, rotor motor B, rotor motor C and rotor motor D respectively, HA, HB, HC and HD are the standard air pressures at the standard speeds of standard rotor motors A, B, C and D respectively; when the wind speed vector The decomposition scalar in the vertical direction is B Z When i is less than zero, it indicates that the wind speed vector The function of is to press the quadrotor downward, so it is necessary to increase the rotor motor speed to compensate for the quadrotor; when the attribution air pressure is less than the standard air pressure, the lift generated by the quadrotor will be smaller, so it is necessary to increase the rotor electrode speed to compensate; from the formula, when the adjustment speed of the rotor motor is less than zero, the rotor electrode speed needs to be compensated, so the rotor motor speed is increased by |R A |or|R B |or|R C |or|R D |; Correspondingly, when the adjustment speed of the rotor motor is greater than zero, the speed of the rotor motor is respectively reduced by |R A |or|R B |or|R C |or|R D |;

[0046] The tilt angle adjustment value and the rotation speed of each rotor motor are used as adjustment parameters, and the flight of the quadrotor aircraft is adjusted according to the adjustment parameters;

[0047] Step 3: After each adjustment, an environment repetition perception instruction is sent to the environment perception module 101 to obtain an adjustment demand index. When the adjustment demand index is greater than the set adjustment threshold, steps 1 to 2 are repeated to perform flight adjustments of the quadrotor aircraft until the demand index is less than or equal to the set adjustment threshold. This indicates that the impact of the environment on the quadrotor aircraft is negligible, and the current flight state can be maintained.

[0048] By adjusting the flight posture and rotor speed according to the environmental conditions, the quadrotor can adapt to the flight environment under different wind speed and air pressure conditions. By sending repeated environmental perception instructions and making repeated adjustments based on the adjustment demand index, the quadrotor can adjust to environmental changes more promptly and maintain a stable flight state. It achieves more refined flight adjustments, enhanced environmental adaptability, faster adjustment response speed and a complete automated flight adjustment process, which can reduce the complexity of operations and improve the intelligence and autonomy of the aircraft.

[0049] The above contents are merely examples and explanations of the structure of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A quadrotor control system based on visual SLAM, including a server, an environment perception module and a flight control module; characterized in that: The server communicates with the visual sensor to obtain visual information of the environment, and uses the SLAM algorithm to process the visual information to build an environmental map in real time and locate the position of the quadcopter in real time; the environmental perception module performs real-time fluctuation analysis on the environment in which the quadcopter is located based on the environmental information to determine the degree of its impact on the flight of the quadcopter, and generates proofreading control instructions based on this information and sends them to the flight control module; When the flight control module receives the calibration control command, it performs a decomposition analysis based on the environmental state of the quadcopter to obtain the control parameters, and adjusts the flight of the quadcopter according to the adjustment parameters; specifically: Step 1: Retrieve the apparent wind speed vector corresponding to the current moment , and decompose it along the rotor coordinate axis to obtain the scalars about the four rotor axes recorded as rotor scalars, where the rotor scalars are , , and , representing the wind speed vector The decomposition scalar in the vertical direction is B Z i; retrieve the wind speed vector direction, and based on this, the resistance posture of the quadrotor is generated, and its resistance posture is related to the wind speed vector The inclination angle of the current quadrotor aircraft rotation plane and the inclination angle of the rotation plane of the resistance posture are obtained, and the difference between the two is calculated to obtain the inclination angle adjustment value, and the inclination angle of the current quadrotor aircraft is adjusted by the inclination angle adjustment value to convert it into the resistance posture; Step 2: Retrieve the air pressure at each detection point of the quadrotor at the current moment, and divide each detection point on the surface of the quadrotor fuselage into corresponding rotor motors according to their positions, thereby obtaining the air pressure corresponding to each rotor motor, and calculating the average value to obtain the corresponding air pressure of each rotor motor, which is recorded as A Qi , B Qi , C Qi and B Qi ; Using the set formula Calculate and obtain the adjusted speed R of each rotor motor A , R B , R C and R D , where d1, d2, d3, d4, d5, d6, d7, and d8 are the set proportional coefficients, A , δ B , δ C , δ D are the speed conversion coefficients of rotor motor A, rotor motor B, rotor motor C and rotor motor D respectively, HA, HB, HC and HD are the standard air pressures at the standard speeds of standard rotor motors A, B, C and D respectively; the tilt angle adjustment value and the speed of each rotor motor are used as adjustment parameters, and the flight adjustment of the quadrotor aircraft is performed according to the adjustment parameters; Step 3: After each adjustment, send an environmental repetition perception command to the environmental perception module to obtain an adjustment demand index. When the adjustment demand index is greater than the set adjustment threshold, repeat steps 1 to 2 to perform flight adjustments on the quadcopter until the demand index is less than or equal to the set adjustment threshold, then maintain the current flight state.

2. The quadrotor control system based on visual SLAM according to claim 1, characterized in that: The specific process of real-time fluctuation analysis of the environment in which the quadrotor is located based on environmental information is as follows: 201: Retrieve the wind speed corresponding to each acquisition time; establish a three-dimensional coordinate with the quadrotor as the origin, and decompose and reorganize the wind speed corresponding to each detection point to obtain a corresponding wind speed scalar, draw a wind speed vector in the three-dimensional space according to the wind speed direction according to the corresponding wind speed scalar, and conduct in-depth analysis to obtain a wind speed change index; 202: Retrieving the air pressure at each detection point on the surface of the quadrotor aircraft at each collection time, and analyzing the air pressure uniformity on the surface of the quadrotor aircraft based on the air pressure uniformity to obtain the air pressure performance value corresponding to each collection time; and then performing trend analysis based on the air pressure performance value corresponding to each collection time to obtain the air pressure change index; 203: Perform numerical analysis on the wind speed variation index and the air pressure variation index to obtain an adjustment demand index. When the adjustment demand index is greater than a set demand threshold, a calibration control instruction is generated and sent to the control module.

3. The quadrotor control system based on visual SLAM according to claim 2, characterized in that: The specific process of decomposing and reorganizing the wind speed corresponding to each detection point is: The quadcopter is taken as the origin, the forward direction of the quadcopter is taken as the horizontal axis, namely the X-axis; the vertically upward direction perpendicular to the origin is taken as the positive direction of the vertical axis, namely the Z-axis; the vertical axis perpendicular to the horizontal and vertical axes is taken as the Y-axis; thus, three-dimensional coordinates can be established; the wind speed of each detection point on the surface of the quadcopter is decomposed in the three-dimensional coordinates to obtain the decomposed wind speed of each detection point; thus, the wind speed of each detection point in the three-dimensional coordinates can be obtained; the set formula is used to calculate and obtain the corresponding expressed wind speed scalar; according to the expressed wind speed, the wind speed direction is plotted in the three-dimensional space according to the corresponding expressed wind speed scalar to obtain the expressed wind speed vector.

4. The quadrotor control system based on visual SLAM according to claim 3, characterized in that: The specific process of in-depth analysis of the wind speed vector is as follows: Retrieve the apparent wind speed vector corresponding to each acquisition time, calculate the angle between the apparent wind speed vectors corresponding to adjacent acquisition times, and perform difference calculation on the modulus lengths of the apparent wind speed vectors corresponding to adjacent acquisition times to obtain the wind speed modulus difference; The angle and wind speed modulus difference are numerically analyzed to obtain the change scalar of the wind speed vector corresponding to adjacent acquisition moments; Compare and analyze the change scalar with the set change interval to divide the change scalar into a first-level change scalar, a second-level change scalar and a third-level change scalar, and record the number of the first-level change scalar, the second-level change scalar and the third-level change scalar as the cumulative number of high wind speed changes, medium wind speed changes and low wind speed changes; The first-level change scalar, the second-level change scalar and the third-level change scalar are summed up to obtain the first-level change total value, the second-level change total value and the third-level change total value; The cumulative number of high wind speed changes, the cumulative number of moderate wind speed changes, the cumulative number of low wind speed changes, the total value of first-level changes, the total value of second-level changes and the total value of third-level changes are numerically analyzed to obtain the wind speed change index.

5. The quadrotor control system based on visual SLAM according to claim 2, characterized in that: The specific process of analyzing the pressure uniformity on the surface of a quadrotor aircraft is as follows: The air pressure is compared and analyzed with the set air pressure range to divide the air pressure into primary air pressure, secondary air pressure and tertiary air pressure. The number of primary air pressure, secondary air pressure and tertiary air pressure is counted respectively and analyzed to obtain the air pressure performance value, thereby obtaining the air pressure performance value corresponding to each collection moment.

6. The quadrotor control system based on visual SLAM according to claim 5, characterized in that: The specific process of trend analysis of the air pressure performance value corresponding to the collection time is as follows: A graph of the change of air pressure performance value over time is plotted with time as the horizontal axis and the air pressure performance value as the vertical axis; a tangent line is drawn at the air pressure point, and the tangent expression is obtained by data fitting, and the air pressure derivative corresponding to each air pressure point is obtained by derivative operation; the air pressure derivatives greater than zero are summed to obtain the pressure influence single value, and the air pressure derivatives less than zero are summed and the absolute value is taken to obtain the pressure single value reduction, and the number of air pressure derivatives equal to zero is counted and recorded as the air pressure stability value; the air pressure performance value, the air pressure influence single value increase, the air pressure single value reduction and the air pressure stability value are numerically analyzed to obtain the air pressure change index.

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