CN111077910B - An anti-collision method for UAV swarms based on UV light guidance - Google Patents

Abstract

An anti-collision system, device and method for UAV swarms based on ultraviolet light guidance, including an information processing center communication connection signal transmitter and a signal receiver. The signal transmitter is composed of two wavelengths of ultraviolet LED light sources and an intensity modulator. , the signal receiver is composed of filters, photoelectric converters, amplifiers and photoelectric signal processors corresponding to two wavelengths of ultraviolet LED light sources; the ultraviolet MIMO device is installed on the drone, and the ultraviolet MIMO device has two different wavelengths The ultraviolet LED light source emits ultraviolet light. According to the ultraviolet light emitted by the ultraviolet LED light source received by the filters in different directions and the number of ultraviolet lights of different wavelengths received, the direction of the drone and the warning level area are determined, thereby making Issue appropriate anti-collision instructions. The invention can realize anti-collision work without relying on external positioning devices such as GPS when drones are operating in a swarm, and is highly flexible and highly intelligent. The ultraviolet MIMO device is light and easy to carry, can work around the clock, and realize secret communication.

Description

An anti-collision method for UAV swarms based on ultraviolet light guidance

Technical field

The invention belongs to the field of optoelectronic information technology, and specifically relates to a method for anti-collision of UAV swarms based on ultraviolet light guidance.

Background technique

With the rapid development of the drone industry and the continuous innovation of its industrial technology, drones have been widely used in many fields such as aerial photography, aerial survey, inspection, agriculture, logistics, and security. Due to its high flexibility, good maneuverability, fast response speed, and low operating requirements, UAVs have gradually played an increasingly important role in military, civilian, technological and other fields. With the introduction of relevant policies such as the opening of low-altitude airspace and drone control in recent years, as well as the gradual maturity of multi-agent systems, the drone industry and market will further develop.

Whether it is civilian stage performances, aerial photography of large-scale events, or military aerial reconnaissance or swarm operations, as long as it is a joint operation of multiple drones, there are processes such as trajectory planning, formation assembly, formation maintenance and transformation. No matter which process they are in, there is a high or low risk of collision between drones. To complete the mission, we must first ensure the flight safety of each drone. Therefore, the problem of anti-collision between swarm drones is Can not be ignored. The current methods used for UAV anti-collision mainly include allowing UAVs to fly strictly according to pre-designed collision-free routes based on GPS, and using visual, acoustic and infrared sensors to identify and avoid obstacles. However, GPS may fail, and visual, acoustic, and infrared sensors also have shortcomings such as being unsuitable for working in low-light conditions and having short detection distances. Therefore, we are looking for a method that does not rely on external positioning facilities such as GPS and has strong environmental adaptability. Anti-collision methods are urgently needed.

Since the "sun blind" ultraviolet light of 200nm-280nm is strongly absorbed by ozone molecules in the atmosphere, wireless ultraviolet light scattering communication in low-altitude airspace has almost no background noise, enabling all-weather communication, and the ultraviolet light signal itself is not subject to radio interference signals. At the same time, it is difficult to implement long-distance ultraviolet interference, which is suitable for covert communication within the UAV formation. Therefore, the anti-collision method based on "sunblind" ultraviolet light guidance can not only meet the above needs, but also be suitable for more applications because the MIMO device is light and easy to carry, can provide all-weather non-direct line of sight communication, has low background noise, and can communicate covertly. occasion.

Contents of the invention

The purpose of the present invention is to provide an anti-collision system, device and method for UAV swarms based on ultraviolet light guidance, to solve the problems of existing inter-machine anti-collision methods that rely too much on external positioning facilities, harsh applicable conditions, and limited detection distance. Ultraviolet light The MIMO device provides hardware support for the implementation of wireless UV-guided UAV anti-collision solutions.

In order to achieve the above objects, the technical solutions adopted by the present invention are:

An anti-collision system for UAV swarms based on ultraviolet light guidance, including an information processing center communication connection signal transmitter and a signal receiver. The signal transmitter is composed of two wavelengths of ultraviolet LED light sources and an intensity modulator. The signal receiver It consists of filters, photoelectric converters, amplifiers and photoelectric signal processors corresponding to the wavelengths of two ultraviolet LED light sources. The microprocessor module in the information processing center is installed inside the drone;

The ultraviolet LED light source on the signal transmitter lights up and emits ultraviolet light into the atmospheric channel to complete the task of signal transmission. The ultraviolet LED light source is modulated by the intensity modulator, so that the two wavelengths of ultraviolet light in the ultraviolet LED light source are The farthest light transmission distance reaches the preset early warning zone boundary values, which are set to 10m and 80m respectively. The three-dimensional space around each drone is divided into three early warning level areas, respectively level 0. The early warning area R>80m, the first-level early warning area 10m<R≤80m, the second-level early warning area R≤10m, where R is the radius of the sphere with the center of mass of the drone as the center of the sphere;

The filter corresponding to the ultraviolet LED light source in the signal receiver receives the ultraviolet signal and converts it into an electrical signal through a photoelectric converter, which is then amplified by an amplifier and then transmitted to the photoelectric signal processor for processing and analysis;

The photoelectric signal processor transmits the processing results to the information processing center. The microprocessor module in the information processing center integrates the information coming from all directions and makes anti-collision instructions, which are issued by the information processing center to the flight of the drone. Control module to adjust the course and speed of the drone.

Further, the model of the microprocessor module is STM32F407.

An anti-collision device based on ultraviolet light-guided UAV swarm. The anti-collision device is an ultraviolet MIMO device. The ultraviolet MIMO device is spherical. A unidirectional transceiver structure is placed on the outer wall of the ultraviolet MIMO device. The unidirectional transceiver structure Including UV LED light source and filter, the unidirectional transceiver structure can adjust the UV LED light source emission elevation angle, beam aperture angle, power and filter parameters; the UV MIMO device is equipped with an intensity modulator, a photoelectric converter, Amplifier and optoelectronic signal processor; the ultraviolet MIMO device consists of upper and lower halves, which are installed above and below the drone fuselage respectively.

Further, the outer wall of the ultraviolet MIMO device takes a longitude line every 90°, and takes a latitude line 45° above and below. There are 8 intersection points of the longitude and latitude lines. A set of unidirectional transceiver structures is placed at each intersection point. In the ultraviolet MIMO device Unidirectional transceiver structures in different directions are marked with serial numbers.

An anti-collision method for UAV swarms based on UV light guidance, including the following steps:

The anti-collision device UV MIMO device is spherical. A unidirectional transceiver structure is placed on the outer wall of the UV MIMO device. The unidirectional transceiver structure includes a UV LED light source and a filter. The unidirectional transceiver structure can adjust the emission elevation angle and beam aperture of the UV LED light source. angle, power and filter parameters; the UV MIMO device is equipped with an intensity modulator, a photoelectric converter, an amplifier and a photoelectric signal processor; the UV MIMO device is composed of upper and lower halves, which are installed on the UAV machine respectively. above and below the body; the outer wall of the ultraviolet MIMO device takes a longitude line every 90°, and takes a latitude line 45° above and below. There are 8 intersections between the longitude and latitude lines, and a set of unidirectional transceiver structures is placed at each intersection. The unidirectional transceiver structures in different directions in the MIMO device are marked with serial numbers;

Step 1: Divide collision warning level areas:

The two wavelengths of ultraviolet LED light sources in the ultraviolet MIMO device can artificially divide the three-dimensional space around the drone into three collision warning level areas, namely the level 0 warning area R>80m and the level 1 warning area 10m<R≤ 80m, level 2 warning zone R≤10m, the higher the level, the higher the collision probability, where R is the radius of the sphere with the center of mass of the drone as the center;

Step 2: Determine the collision warning area:

Take two drones A and B as an example. The eight UV LED light sources in different directions on the UV MIMO device of drone A are cyclically lit. The UV LEDs of different wavelengths received by the signal receiver of drone B are The number of light sources determines which level of warning zone you are in for UAV A:

If UAV B’s signal receivers in all directions do not receive UV LED signals of any wavelength, then UAV B is in the level 0 warning zone of UAV A, and there is no danger of collision for the time being. It will fly along the original heading. Can;

If the signal receiver in a certain direction of UAV B receives a UV LED signal of one wavelength, then UAV B is in the level 1 warning zone of UAV A. The distance between the two aircraft is relatively close, and there is a certain probability. If there is a risk of collision, skip to step 3;

If the signal receiver in a certain direction of drone B receives ultraviolet LED signals of two wavelengths, drone B is in the level 2 warning zone of drone A. The distance between the two drones is too close, and there is If there is a greater risk of collision, skip to step 4;

Step 3, adjust flight speed:

The information processing center issues an execution command to adjust the flight speed to the flight control module, reducing the drone's flight speed to less than 8m/s, and continuously paying attention to the ultraviolet light signal in that direction;

Step 4: Adjust flight direction

The information processing center issues an execution command to adjust the flight direction to the flight control module. At this time, UAV B quickly adjusts the flight direction according to the adjustment plan.

Further, the adjustment plan described in step 4 is as follows:

Situation A: When only receiving UV LED signals of two wavelengths from a drone: quickly adjust the flight direction to the opposite direction of the signal receiver until only one wavelength of UV LED signals can be received , then adjust the flight direction again according to the current position and target position;

Situation B: When receiving ultraviolet LED signals of two wavelengths from multiple drones, there are two situations:

Situation a: When the coming directions of multiple drones are asymmetrically offset, quickly adjust the flight direction to the opposite direction of the combined direction of several signal receivers until only one wavelength of ultraviolet LED signal can be received. At this time Re-adjust the flight direction based on the current position and target position;

Situation b: When the coming directions of multiple drones are symmetrically offset, the flight direction is quickly adjusted to the opposite direction of the original flight direction until only one wavelength of ultraviolet LED signal is received. At this time, the drone is re-accorded to the current position and target. The position of the rally point adjusts the flight direction.

The beneficial effects of the present invention are:

When UAV swarms are operating, no matter which process they are in formation assembly, disbandment, formation maintenance and transformation, as long as each UAV is equipped with the above-mentioned ultraviolet guidance and anti-collision system, it can achieve independent The anti-collision work of external positioning devices such as GPS is highly flexible and intelligent. Secondly, the UV LED light source on the UV MIMO device has a simple structure, is easy to control, and is cheap; the UV MIMO device is light and easy to carry, and will not increase the burden on the drone. Finally, the "sun-blind" ultraviolet light has low background noise and can work around the clock, which can greatly improve the safety of the drone swarm in various operating situations. Due to the characteristics of the "sun-blind" ultraviolet light itself, covert communication can be achieved, making the system Can be applied to wider scenarios.

Description of the drawings

Figure 1 is a schematic diagram of a UAV swarm anti-collision system based on ultraviolet light guidance;

Figure 2 is a schematic diagram of an ultraviolet MIMO device;

Figure 3 is a schematic diagram of the anti-collision warning area;

Figure 4 is a schematic diagram of the direction adjustment plan when only one drone warning signal is received;

Figure 5 is a schematic diagram of the direction adjustment scheme when the coming directions of multiple UAVs are asymmetrically offset;

Figure 6 is a schematic diagram of the direction adjustment scheme when the coming directions of multiple UAVs are symmetrically offset.

In the figure, 1-information processing center, 2-signal transmitter, 3-signal receiver, 4-microprocessor module, 5-UV LED light source, 6-intensity modulator, 7-optical filter, 8-photoelectric Converter, 9-amplifier, 10-photoelectric signal processor, 11-spherical MIMO device, 12-drone, 13-unidirectional transceiver structure, 14-flight control module, 15-ultraviolet light.

Detailed ways

The present invention will be described in detail below with reference to the drawings and specific embodiments.

As shown in Figure 1, a UAV swarm anti-collision system based on ultraviolet light guidance is communicated by an information processing center 1 to connect a signal transmitter 2 and a signal receiver 3. The signal transmitter 2 is composed of two wavelengths of "sunblind" It is composed of an ultraviolet LED light source 5 and an intensity modulator 6. The signal receiver 3 is composed of a filter 7 corresponding to the wavelength of two "sun blind" ultraviolet LED light sources, a photoelectric converter 8, an amplifier 9 and a photoelectric signal processor 10. The microprocessor module 4 in the information processing center 1 is installed inside the drone 12, and the model of the microprocessor module 4 is STM32F407.

As shown in Figure 2, a longitude line is taken every 90° on the outer wall of the ultraviolet MIMO device 11, and a latitude line is taken 45° up and down. There are 8 intersection points for the longitude and latitude lines. A set of unidirectional transceiver structures 13 are placed at each intersection point. This structure It includes two ultraviolet LED light sources 5 with different wavelengths (λ ₁ , λ ₂ ) and filters 7 of corresponding wavelengths. Adjust the appropriate emission elevation angle, beam aperture angle, power and filter 7 parameters of the ultraviolet LED light source 5. The light receiving range of the filter 7 in each direction and the ultraviolet light 15 emitted by the ultraviolet LED light source 5 can just cover one-eighth of the area responsible for this direction.

The intensity modulator 6, the photoelectric converter 8, the amplifier 9 and the photoelectric signal processor 10 are all installed inside the ultraviolet MIMO device 11. The ultraviolet MIMO device 11 is composed of upper and lower halves, which are respectively installed on the fuselage of the drone 12. above and below. The unidirectional transceiver structures 13 in different directions in each UV MIMO device 11 are marked with serial numbers.

The ultraviolet LED light sources 5 on the signal transmitter 2 light up in sequence, and the ultraviolet LED light sources 5 with the same serial number and different wavelengths light up at the same time and emit ultraviolet light 15 into the atmospheric channel to complete the task of signal transmission.

The filter 7 corresponding to the two wavelength LED light sources in the signal receiver 3 receives the ultraviolet light 15 signal and converts it into an electrical signal through the photoelectric converter 8 and then amplifies it through the amplifier 9 and then transmits it to the photoelectric signal processor 10 for processing. analyze.

The photoelectric signal processor 10 in each direction transmits the processing results to the information processing center 1. The microprocessor module 4 in the information processing center 1 integrates the information from each direction and makes appropriate anti-collision instructions. The center 1 issues the flight control module 14 to the drone to adjust the drone's heading, speed and other flight conditions.

The ultraviolet LED light sources 5 of two wavelengths installed at the intersection of latitude and longitude lines on the surface of the ultraviolet MIMO device 11 are respectively modulated to appropriate intensities by the intensity modulator 6, so that the farthest transmission distances of the ultraviolet light of the two wavelengths reach the preset warning respectively. The zone boundary values, namely 10m and 80m, enable the three-dimensional space around each UAV 12 to be divided into three early warning level zones, as shown in Figure 3 .

An anti-collision method for UAV swarms based on UV light guidance, including the following steps:

Step 1: Divide collision warning level areas:

The two wavelengths of LED light sources 5 in the ultraviolet MIMO device 11 can artificially divide the three-dimensional space around the drone 12 into three collision warning level areas, as shown in Figure 3, which are respectively level 0 warning areas (R>80m). , Level 1 early warning area (10m<R≤80m), Level 2 early warning area (R≤10m), the higher the level, the higher the collision probability, where R is the radius of the sphere with the center of mass of the drone as the center.

Step 2: Determine the collision warning area:

Taking two UAVs A and B as an example, the UV LED light sources 5 in several directions on the UV MIMO device 11 of UAV A are cyclically lit, and UAV B lights up according to the different wavelengths of UV light received by the signal receiver 3. The number of light LED signals determines which level of warning zone you are in for UAV A:

If the signal receiver 3 of UAV B in all directions does not receive any ultraviolet LED signal of any wavelength, then UAV B is in the level 0 warning zone of UAV A, and there is no danger of collision for the time being, and it will fly along the original heading. That’s it;

If the signal receiver in a certain direction of UAV B receives a UV LED signal of one wavelength, UAV B is in the level 1 warning zone of UAV A, and the distance between the two aircraft is relatively close. There is a certain probability of collision risk, skip to step 3;

If the signal receiver 3 in a certain direction of UAV B receives ultraviolet LED signals of two wavelengths, UAV B is in the Level 2 warning zone of UAV A, and the distance between the two UAVs is too close. If there is a greater risk of collision, skip to step 4;

Step 3, adjust flight speed:

The information processing center 1 issues an adjustment flight speed execution command to the flight control module 14 to reduce the UAV flight speed to less than 8m/s and continue to pay attention to the ultraviolet light signal in this direction.

Step 4, adjust the flight direction:

The information processing center 1 issues an execution command to adjust the flight direction to the flight control module 14. At this time, the drone B quickly adjusts the flight direction according to the adjustment plan.

In actual scenarios, since the distance limits of each warning zone of each drone are the same, ignoring the impact of some uncontrollable factors on the ultraviolet light propagation distance, it can be understood that A is in a certain level of warning zone of B, and B is also in a certain level of warning zone of B. A certain level of early warning zone, so when there is a risk of collision, the two drones will adjust their flight directions at the same time.

The specific adjustment plans are as follows:

Situation A: When only receiving UV LED signals of two wavelengths from a drone, quickly adjust the flight direction to the direction opposite to the signal receiver 3 directions until only one wavelength of UV LED is received signal, and then adjust the flight direction again according to the current position and target position.

For example: The signal receiver 3 in the direction of drone B ② receives ultraviolet LED signals of two wavelengths, and drone B quickly adjusts its flight direction to the opposite direction of ② as shown in Figure 4 ⑧.

Situation B: When receiving ultraviolet LED signals of two wavelengths from multiple drones, there are two situations:

Situation a: When the coming directions of multiple drones are asymmetrically offset, quickly adjust the flight direction to the opposite direction of the 3-direction composite direction of several signal receivers until only one wavelength of ultraviolet LED signal can be received. Re-adjust the flight direction according to the current position and target position.

Example: The signal receiver 3 in the ②, ④, and ⑦ directions of UAV B all receives ultraviolet LED signals of two wavelengths. Then B quickly adjusts the flight direction to the inverse of the combined direction of ②, ④, and ⑦ as shown in Figure 5. direction.

Situation b: When the coming directions of multiple drones are symmetrically offset, the flight direction is quickly adjusted to the opposite direction of the original flight direction until only one wavelength of ultraviolet LED signal is received. At this time, the drone is re-accorded to the current position and target. The position of the rally point adjusts the flight direction.

Example: The signal receiver 3 in the ①, ③, ⑤, and ⑦ directions of UAV B all received ultraviolet LED signals of two wavelengths. These directions just offset each other, and UAV B quickly adjusted its flight direction as shown in the figure. The opposite direction of the original heading shown in 6.

In addition, the collision avoidance scheme of various collision modes is analyzed and a collision avoidance scheme library is established so that the appropriate collision avoidance scheme can be directly called when encountering the same situation in the future.

Although specific embodiments of the present invention have been described above, those skilled in the art will understand that these are only examples, and the protection scope of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims (1)

1. The anti-collision method for the unmanned aerial vehicle bee colony based on ultraviolet light guidance is characterized in that an anti-collision ultraviolet light MIMO device is spherical, a unidirectional receiving and transmitting structure is arranged on the outer wall of the ultraviolet light MIMO device, the unidirectional receiving and transmitting structure comprises an ultraviolet light LED light source and an optical filter, and the unidirectional receiving and transmitting structure can adjust parameters of the ultraviolet light LED light source emission elevation angle, the beam aperture angle, the power and the optical filter; the ultraviolet MIMO device is internally provided with an intensity modulator, a photoelectric converter, an amplifier and a photoelectric signal processor; the ultraviolet MIMO device consists of an upper half part and a lower half part, and is respectively arranged above and below the unmanned aerial vehicle body; the outer wall of the ultraviolet light MIMO device takes a warp every 90 degrees, the upper and lower 45 degrees respectively take a weft, the warp and the weft have 8 intersection points, a group of unidirectional receiving and transmitting structures are placed at each intersection point, and the unidirectional receiving and transmitting structures in different directions in the ultraviolet light MIMO device are marked with serial numbers;

the method comprises the following steps:

step 1, dividing a collision early warning grade area:

the ultraviolet LED light sources with two wavelengths in the ultraviolet MIMO device can divide the three-dimensional space around the unmanned aerial vehicle into three collision early warning level areas, wherein R is more than 80m, R is more than 10m and less than 80m, R is more than 10m, and R is more than 10m, wherein R is the radius of a sphere with the center of mass of the unmanned aerial vehicle as the center of sphere;

step 2, judging a collision early warning area:

taking two unmanned aerial vehicles A, B as an example, 8 ultraviolet light LED light sources in different directions on an ultraviolet light MIMO device of an unmanned aerial vehicle A are circularly lightened, and an unmanned aerial vehicle B judges that the unmanned aerial vehicle B is positioned in several grades of early warning areas of the unmanned aerial vehicle A according to the number of ultraviolet light LED light sources with different wavelengths received by a signal receiver:

if the signal receivers in all directions of the unmanned plane B do not receive ultraviolet light LED signals with any wavelength, the unmanned plane B is positioned in a 0-level early warning area of the unmanned plane A, no collision danger exists temporarily, and the unmanned plane B can fly along the original course;

if the signal receiver of the unmanned plane B in a certain direction receives an ultraviolet LED signal with one wavelength, the unmanned plane B is positioned in a 1-level early warning area of the unmanned plane A, the distance between the unmanned plane B and the unmanned plane A is relatively close, and the unmanned plane B has a collision risk with a certain probability and jumps to the step 3;

if the signal receiver of the unmanned plane B in a certain direction receives ultraviolet light LED signals with two wavelengths, the unmanned plane B is positioned in a 2-level early warning area of the unmanned plane A, the distance between the unmanned planes is too close, the collision risk is high, and the step 4 is skipped;

step 3, adjusting the flying speed:

an information processing center issues an execution command for adjusting the flight speed to a flight control module, the flight speed of the unmanned aerial vehicle is reduced to below 8m/s, and the ultraviolet light signal in the direction is continuously focused;

step 4: adjusting the flight direction:

the information processing center issues an execution command for adjusting the flight direction to the flight control module, and at the moment, the unmanned aerial vehicle B rapidly adjusts the flight direction according to an adjustment scheme, wherein the adjustment scheme is as follows:

case a: when only ultraviolet LED signals with two wavelengths of one unmanned plane are received: rapidly adjusting the flight direction to be the opposite direction of the signal receiver direction until only ultraviolet light LED signals with one wavelength can be received, and at the moment, adjusting the flight direction again according to the current position and the target position;

case B: when receiving the ultraviolet light LED signals of two wavelengths of a plurality of unmanned aerial vehicles, two conditions are as follows:

case a: when the coming directions of the multiple unmanned aerial vehicles are asymmetrically offset, the flight direction is quickly adjusted to be opposite to the direction combining direction of the signal receivers until only ultraviolet light LED signals with one wavelength can be received, and at the moment, the flight direction is adjusted again according to the current position and the target position;

case b: when the coming directions of the multiple unmanned aerial vehicles are offset symmetrically, the flight direction is quickly adjusted to be the opposite direction of the original flight direction until only ultraviolet light LED signals with one wavelength can be received, and at the moment, the flight direction is adjusted again according to the current position and the position of the target set node.