CN110082722B

CN110082722B - Method for positioning flying light source under indoor fixed obstacle condition based on white light LED

Info

Publication number: CN110082722B
Application number: CN201910356144.3A
Authority: CN
Inventors: 金杉; 崔文; 金志刚
Original assignee: Tianjin University
Current assignee: Tianjin University
Priority date: 2019-04-29
Filing date: 2019-04-29
Publication date: 2022-06-10
Anticipated expiration: 2039-04-29
Also published as: CN110082722A

Abstract

The invention relates to a method for positioning a flying light source based on a white light LED under the condition of indoor fixed obstacle, which comprises the following aspects: the method comprises the following steps that more than two convex mirrors are arranged on the ground at two ends of a flight channel between adjacent obstacles, receivers with the same height as the obstacle on the higher side of the channel are arranged right above each convex mirror, the receiving directions face right below, the arrangement angles of the convex mirrors meet the requirement that incident light beams emitted by a white light LED in a channel space can be at least reflected to one receiver, and photoelectric signals collected by each receiver are transmitted to a convergence center; according to the principle that different incident angles and different photoelectric energy are formed on multiple receivers by the same white light LED, the convergence center performs comparative analysis to obtain the change condition of the horizontal movement position of the linear positioning object and determine the behavior state of the linear positioning object. The head and the tail of the positioning object are respectively provided with a white light LED which emits light beams with the center vertical to the machine body and the irradiation angle range fixed.

Description

Method for positioning flying light source under indoor fixed obstacle condition based on white light LED

Technical Field

The invention relates to the technical field of visible light communication, in particular to a method for positioning a flight light source based on a white light LED under the condition of indoor fixed obstacle.

Background

With the development and progress of white light LED technology, white light LEDs with the advantages of high brightness, low power consumption, long lifetime, etc. have gradually replaced fluorescent lamps and incandescent lamps. The white light LED communication is convenient to modulate and quick in response, has obvious advantages in the aspects of harmless radiation, confidentiality, stability and the like compared with the modes of infrared, ultraviolet, radio frequency and the like, becomes a novel Visible Light Communication (VLC) mode, and is gradually popularized to the field of indoor positioning. The existing LED positioning method can maintain the stability of a channel and has strong operability, but a targeted model is lacked for the requirement of tracking, positioning and sampling of an indoor flying target, and the acquisition and processing research of radio frequency signals under the condition of a single light source and multiple receivers is less.

Specifically, in some large warehouses and unmanned workshops, the traditional GPS positioning has the characteristics of wireless weak current signal shielding, positioning error and position delay judgment. These characteristics make the user have many problems in that the positioning data greatly differs from the actual flight behavior, the state of the mobile device is wrongly determined, and the like. And for positioning objects, electromagnetic radiation generated by various indoor modern electric equipment brings great challenges to the normal operation of the positioning terminal. Since the electromagnetic radiation interference of the electrical equipment and the flight state of the positioning object can seriously affect the positioning efficiency, it becomes a great challenge in the positioning system design to research how to fully utilize the incident light to determine the behavior characteristics of the flight target, avoid or reduce the interference, and avoid the flight positioning delay and error measures.

The invention is based on a light beam receiving and transmitting system of a white light LED, establishes two ends of the bottom of a flight channel between obstacles (a goods shelf and a machine) indoors, and is provided with convex mirrors, and the mirror reflection angle can reflect light beams emitted by the white light LED on a rotor unmanned aerial vehicle to the positions right above the convex mirrors at the two ends of the flight channel; on the two receivers, a white light LED which is perpendicular to the body and fixed in the irradiation angle range is respectively arranged at the head and the tail of a positioning object (a rotor unmanned aerial vehicle), a data acquisition basic model is established according to different incident angles and different photoelectric energies formed by establishing the same white light LED on the receivers, and the gathering centers connected with all the receivers are subjected to comparative analysis to obtain the linear flight state change condition of the positioning object and determine the behavior state of the positioning object. The white light LED positioning method designed on the basis of the model completely avoids the interference of electromagnetic radiation of electrical equipment to the working condition of the positioning terminal indoors, can provide position information quickly and accurately and improves the positioning efficiency.

Disclosure of Invention

The invention provides a method for positioning a flying light source based on a white light LED under the condition of indoor fixed obstacle, which aims to fully utilize incident light to judge the behavior characteristics of a flying target, scientifically reduce the number of light sources, avoid or reduce interference and avoid the problems of delay and error of flying positioning. In the method, the multiple LED receivers can be reflected by the convex mirror to continuously position the same light source transmitter in the flying process. The technical scheme is as follows:

a method for positioning a flying light source based on a white light LED under the condition of indoor fixed obstacles comprises the following aspects:

(1) the method comprises the following steps that more than two convex mirrors are arranged on the ground at two ends of a flight channel between adjacent obstacles, receivers with the same height as the obstacle on the higher side of the channel are arranged right above each convex mirror, the receiving directions face right below, the arrangement angles of the convex mirrors meet the requirement that incident light beams emitted by a white light LED in a channel space can be at least reflected to one receiver, and photoelectric signals collected by each receiver are transmitted to a convergence center; according to the principle that the same white light LED forms different incident angles and different photoelectric energies on a plurality of receivers, the convergence center performs comparative analysis to obtain the change condition of the horizontal movement position of the linear positioning object and determine the behavior state of the linear positioning object.

(2) The head and the tail of the positioning object are respectively provided with a white light LED which emits light beams with the center vertical to the machine body and the irradiation angle range fixed, the position is fixed, the center point of the light source is kept vertical, the illumination of the light source is unchanged, and the irradiation range is uniform. Different frequencies or waveform differences exist among different positioning light sources so as to avoid mutual interference;

(3) the flight path and speed of the positioning object are not limited, but the horizontal angle is kept to fly stably, and the illumination intensity of the light source is stable and unchanged;

(4) the positioning process should be continuously monitored, and the continuous position of the positioning object can be judged through the change monitoring data obtained by each receiver, so that the flying speed and the flying path are obtained.

Drawings

FIG. 1 is a flow chart of the system of the present invention

FIG. 2 is a multi-receiver arrangement of the present invention

FIG. 3 is a diagram of multi-receiver based positioning decision of the present invention

FIG. 4 is a white light LED and positioning object assembly of the present invention

Fig. 5 is a graph of the present invention continuously monitoring the resulting airspeed and path, and effectively monitoring receiver switching.

Detailed Description

Reference will now be made in detail to implementations of the present invention. The following embodiments will be described with reference to the accompanying drawings for the purpose of illustrating the invention.

FIG. 1 shows the sequence of development of the four steps of the invention, respectively:

(1) determining the setting and testing of a monitoring area and a receiver: the receiver is arranged at two ends of a flight channel formed between adjacent barriers in a large warehouse and an unmanned workshop and at the same height as the barrier on the higher side, and a convex mirror is arranged right below the receiver. The arrangement angles of the two convex mirrors meet the requirement that light beams emitted by the white light LED of the positioning object in the complete space of the channel can be reflected to receivers at two ends.

(2) White light LED setting and testing: and setting a light source according to the second step. The 2 receivers in the same channel are used for testing the illumination continuous stability of the 2 light sources of the positioning object. The light source is placed in the channel space to be lightened, and whether 2 receivers can correctly acquire position data together is tested.

(3) Positioning object setting and light source installation: and (3) on the basis of the step (2), white light LEDs which are respectively arranged at the head and the tail of the flying positioning object, emit light beams with the centers vertical to the airplane body and have fixed irradiation angle ranges, and are fixed in position. A sensor mainboard and a battery module are arranged in the positioning object, and whether the flight behavior of the positioning object is normal or not and whether the light source has no obvious vibration or not are tested.

(4) The positioning object with the light source continuously flies and positions the test: and (3) testing the position and track determination of the positioning object during variable-speed and variable-direction flight in a remote control mode on the basis of (1), (2) and (3), and comparing the accuracy with the video. When the test positioning object flies, the self-switching condition of the positioning data source is influenced due to the change of the illumination intensity of the incident light of each receiver.

Figure 2 shows a multi-receiver arrangement. The indoor requirements for the monitoring area are that each corner is [90 °, 180 ° ].

(1) Fig. 2(a) is a sectional view of the underside of a suspended ceiling. All the receivers (A and B) are uniformly arranged indoors. When any emitter alpha is required to be lighted, the light signal generated when the channel between the obstacles flies is reflected by the convex mirror (A, B), so that the effective receiving of 2 or more receivers can be obtained, and the positioning data is generated at the convergence center. Two adjacent convex mirrors on the ground at two ends of the same channel can transmit the LED light beams of the positioning objects to a receiver right above the two convex mirrors at the same time.

(2) Fig. 2(b) is a cross-sectional view of the location of any receiver in a room, where the direction of the reflected line is facing upward approximately vertically. And a convex mirror is arranged below the indoor suspended ceiling. The number of indoor receivers (more than or equal to 2) is determined by working modes and monitoring requirements, and each receiver is required to perform circuit and network wiring in a suspended ceiling, connect an alternating current power supply and gather a center. In the receiving area, the receiver is arranged to receive the reflected light beam of the convex mirror.

Fig. 3 is a multi-receiver based positioning decision. For any positioning object alpha equipped with a white light LED, at a certain point of time, the receivers A and B are respectively 2 receivers with the strongest incident illumination intensity, and the positioning data is comprehensively determined. Two directed broken lines in the graph are the tracing directions of the receivers, at this time, the positions of incident light rays received by the receivers A and B are taken, possible rays A alpha and B alpha exist in the same channel range, a point where the rays A alpha and B alpha coincide exists is obtained through analysis, and the position where the object alpha is located at the moment is obtained.

FIG. 4 is a white light LED and positioning object assembly. The positioning object is a rotor unmanned aerial vehicle, the flight path and the speed of the positioning object are not limited, but the flight path and the speed of the positioning object are not limited, and the conditions of vibration, overturning and the like cannot occur. The head and the tail of the flying positioning object are respectively provided with a white light LED which emits light beams with the center vertical to the airplane body and the irradiation angle range fixed, and the positions are fixed. The emitted light beams are in opposite directions and are not received by the same receiver. The central axis of the beam is perpendicular to the horizontal forward flight direction. In the flight process, the unmanned aerial vehicle is controlled to act in a remote control mode, the battery energy storage equipment is carried by the positioning object, and the stability of flight and power supply of the front and rear end light sources is ensured.

FIG. 5 is a graph of the flight velocity and path from continuous monitoring of step position during the flight of a located object, and receiver switching for effective monitoring. When the positioning object is positioned at the position 1, the position information of the positioning object alpha is determined by the receivers A and B; after flying to position 2, the position information of the positioning object is still determined by the receivers A and B.

Claims

1. A method for positioning a flying light source based on a white light LED under the condition of indoor fixed obstacles comprises the following aspects:

(1) the method comprises the following steps that more than two convex mirrors are arranged on the ground at two ends of a flight channel between adjacent obstacles, receivers with the same height as the obstacle on the higher side of the channel are arranged right above each convex mirror, the receiving directions face right below, the arrangement angles of the convex mirrors meet the requirement that incident light beams emitted by a white light LED in a channel space can be at least reflected to one receiver, and photoelectric signals collected by each receiver are transmitted to a convergence center; according to the principle that the same white light LED forms different incident angles and different photoelectric energies on a plurality of receivers with different positions, the convergence center performs comparative analysis to obtain the change condition of the horizontal movement position of the positioning object and determine the behavior state of the positioning object;

(2) the head and the tail of the positioning object are respectively provided with a white light LED which emits a light beam with the center vertical to the machine body and the irradiation angle range fixed, the position is fixed, the center point of the light source is kept vertical, the illumination of the light source is unchanged, and the irradiation range is uniform; different positioning light sources are different in frequency or have waveform difference so as to avoid mutual interference;