Indoor positioning method, equipment and medium

Abstract

The invention relates to the technical field of indoor positioning, and discloses an indoor positioning method, equipment and a medium. The method comprises the steps that each LED lamp is coded according to the flicker frequency of the LED lamps, and the coded content is used for transmitting the position information of each LED lamp in the indoor space; imaging images of the N LED lamps are obtained through shooting of an event camera, and light intensity changes, generated by flickering of the LED lamps, of each pixel point in the imaging images are captured, so that an LED lamp flickering event is obtained; decoding the coding content of each LED lamp through the obtained LED lamp flicker event to obtain the position information of each LED in the indoor space; finally, the position information of the mobile station in the indoor space is obtained through the relation between the position information of the N LED lamps in the indoor space and the position information of the event camera in the indoor space, indoor positioning is achieved, and the positioning precision is high.

Description

Technical Field

[0001] The present invention relates to the field of indoor positioning technology, and in particular to an indoor positioning method, equipment and medium. Background Art

[0002] With the popularization of unmanned systems, including automated guided vehicles (AGVs), service robots, indoor drones, etc., indoor precise positioning is the basis for the interaction and coordination of the above-mentioned types of mobile unmanned equipment with other equipment / systems, and is also a key infrastructure for improving the working efficiency of unmanned systems. Common indoor precise positioning technologies include known space positioning solutions based on scene deployment and unknown space positioning solutions that do not require scene deployment. The former is suitable for indoor environments where mobile unmanned equipment has strong interactions with the surrounding environment / facilities, and the latter is only deployed on unmanned mobile equipment to ensure that the equipment can return to the origin after a certain walking process. The former system has strong repeatability and high precision, while the latter has low requirements for environmental modification. Each has its own advantages, so it is usually combined to improve the operating reliability of unmanned mobile equipment.

[0003] Among the known spatial positioning solutions based on scenario deployment, most of them use different wireless communication technologies for scenario deployment, such as ultrasonic positioning, ultra-wideband (UWB) indoor positioning system, Bluetooth Low Energy (BLE) indoor positioning system, etc. The visible light positioning solution based on visible light communication technology is an emerging indoor positioning technology that has emerged in recent years. Due to the short wavelength of visible light, higher positioning accuracy can be obtained by using the algorithm framework of wireless indoor positioning. At the same time, indoor deployment tags can be considered to be combined with lighting systems to reduce various problems caused by additional deployment.

[0004] Among them, the classic visible light positioning system usually uses a photodiode (PD) as a receiving detector, and the communication coding mechanism and position solution scheme follow the various algorithms and implementation frameworks similar to UWB wireless positioning. However, the positioning accuracy of this system is greatly restricted by the synchronization accuracy of the base station deployment, especially for temporary deployment, mobile deployment and other places, the challenge is very great. Some application scenarios use image sensors (IS) as receiving detectors, but because traditional IS sensors have a frame-by-frame imaging mechanism, their imaging results are not time-continuous, which limits the coding scheme of LED base stations and constrains the further in-depth application of this technical path in the field of visible light communications and visible light positioning systems. Summary of the invention

[0005] The object of the present invention is to provide an indoor positioning method, system, device and medium, which can improve the accuracy of indoor positioning.

[0006] In order to solve the above technical problems, an embodiment of the present invention provides an indoor positioning method, which is applied to an indoor positioning system, wherein the indoor positioning system comprises: N LED lights arranged on an indoor ceiling and a mobile station located on the indoor ground, wherein the mobile station is provided with an event camera with a lens facing the indoor ceiling, and N≥3;

[0007] The method comprises:

[0008] Each LED lamp is encoded according to the flashing frequency of the LED lamp, and the encoded content is used to transmit the position information of each LED lamp in the indoor space;

[0009] The imaging images of N LED lights are obtained by shooting with an event camera, and the light intensity change of each pixel point in the imaging image caused by the LED light flickering is captured to obtain the LED light flickering event;

[0010] By obtaining the LED light flashing events, the coded content of each LED light is decoded to obtain the position information of each LED in the indoor space;

[0011] The physical connection line between each LED light and the event camera in the indoor space is projected onto the two-dimensional plane where the imaging image is located, and the relationship between the position information of each LED light in the indoor space and the position information of the event camera in the indoor space is determined by the angle between each LED light and the event camera in the horizontal direction on the two-dimensional plane;

[0012] The position information of the mobile station in the indoor space is obtained by combining the relationship between the position information of the N LED lights in the indoor space and the position information of the event camera in the indoor space.

[0013] In some optional embodiments, the flashing frequencies of the N LED lamps are the same, and the encoded content of each LED lamp is decoded by obtaining the flashing events of the LED lamps to obtain the position information of each LED in the indoor space, including:

[0014] Get multiple identical LED light flashing events at the same time;

[0015] According to the connectivity and similarity between the light intensity changes of each pixel in multiple identical LED light flashing events, the imaging images of N LED lights are divided into regions to obtain the target regions of the N LED lights on the imaging images;

[0016] The code of the LED light corresponding to each target area on the imaging image is obtained, and the position information of each LED light in the indoor space is obtained by decoding.

[0017] In some optional embodiments, encoding each LED lamp according to the flashing frequency of the LED lamp includes:

[0018] Control each LED light to flash in a pulse modulation PWM mode, where the frequency of PWM is the flashing frequency of the LED light; wherein the duty cycle of the pulse width of the PWM mode is used to indicate the relationship between the duration of each LED light being in a bright state and the duration of each LED light being in a dark state during the flashing process;

[0019] Each LED light is encoded by using a 20% duty cycle as character 0 and an 80% duty cycle as character 1.

[0020] In some optional embodiments, decoding the coded content of each LED lamp to obtain the position information of each LED in the indoor space includes:

[0021] The obtained coded content is abstracted into a single flashing PWM waveform, and the characters 0 and 1 are identified according to the duty cycle to decode and obtain the position information of each LED in the indoor space.

[0022] In some optional embodiments, the relationship between the position information of each LED lamp in the indoor space and the position information of the event camera in the indoor space is expressed by the following formula:

[0023]

[0024] Where (x0, y0) represents the location information of the mobile station in the indoor space, (x1, y1),..., (x N ,y N ) represents the position information of N LED lights in the indoor space. They respectively represent the horizontal angles between the N LED lights and the event camera on the two-dimensional plane.

[0025] In some optional embodiments, the step of combining the relationship between the position information of the N LED lamps in the indoor space and the position information of the event camera in the indoor space to obtain the position information of the mobile station in the indoor space includes:

[0026] The location information of the mobile station in the indoor space is obtained by the following formula:

[0027] p=φ T b

[0028]

[0029] Where p represents the location information (x0, y0) of the mobile station in the indoor space, and b is the intermediate value.

[0030] In some optional embodiments, there are four LED lamps, which are respectively disposed at the four corners of the indoor ceiling; or, there are five LED lamps, four of which are respectively disposed at the four corners of the indoor ceiling, and one is disposed at the center of the indoor ceiling.

[0031] Among them, if there are five LED lamps, the four LED lamps respectively arranged at the four corners of the indoor ceiling flash at the same flashing frequency, and the one LED lamp arranged at the center of the indoor ceiling flashes at a flashing frequency different from that of the four LED lamps respectively arranged at the four corners of the indoor ceiling.

[0032] In some optional embodiments, each of the LED lights flashes in an on / off manner, or the LED lights flash by changing the degree of brightness / dimness of the LED lights.

[0033] An embodiment of the present invention also provides a computer device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the above-mentioned indoor positioning method.

[0034] An embodiment of the present invention further provides a computer-readable storage medium storing a computer program, wherein the computer program implements the above-mentioned indoor positioning method when executed by a processor.

[0035] The indoor positioning method provided by the present invention has at least the following beneficial effects:

[0036] Each LED light is encoded with the flickering frequency of the LED light, and the encoded content is used to transmit the position information of each LED light in the indoor space. The imaging image of the LED light is captured by an event camera. Since the event camera can asynchronously capture the light intensity change on a single pixel on the imaging image, the light intensity change of each pixel point caused by the flickering of the LED light can be obtained, and the LED light flickering event can be obtained. Then, the encoded content of each LED light can be decoded through the obtained LED light flickering event to obtain the position information of each LED in the indoor space, so as to detect the position of the subsequent mobile station in the indoor space.

[0037] Among them, the imaging mechanism of the event camera is completely different from that of the traditional IS sensor. There is no time constraint for exposure by frame or row. When controlling each LED light to flash, the flashing frequency can be much higher, so it can carry a lot of information, such as directly using the position information of the LED light in the indoor space, eliminating the application of IS sensors in the field of visible light communication and visible light positioning systems caused by the delay mechanism of framing imaging.

[0038] Moreover, when detecting the position of a mobile station in an indoor space, the position information of multiple LED lights in the indoor space and the horizontal angle between each LED light and the event camera on the imaging plane (i.e., the two-dimensional plane where the imaging image is located) are used. That is, it relies on the geometric relationship between the imaging points of multiple LED lights in the imaging target surface, eliminating the reliance on the synchronization accuracy between multiple base stations in the classic visible light positioning system, thereby reducing the cost and requirements of equipment deployment while ensuring indoor positioning accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] One or more embodiments are exemplarily described by the pictures in the corresponding drawings, and these exemplary descriptions do not constitute limitations on the embodiments.

[0040] Figure 1 is a deployment diagram of an indoor positioning system provided according to an embodiment of the present invention;

[0041] Figure 2 is a flow chart of an indoor positioning method provided according to an embodiment of the present invention;

[0042] Figure 3 is a schematic diagram of a PWM encoding provided according to an embodiment of the present invention;

[0043] Figure 4 is a schematic diagram of the angle between each LED light and the event camera in the horizontal direction on a two-dimensional plane provided according to an embodiment of the present invention;

[0044] Figure 5 It is a structural diagram of a hardware device provided according to an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. However, it will be appreciated by those skilled in the art that in the embodiments of the present invention, many technical details are proposed in order to enable the reader to better understand the present invention. However, even without these technical details and various changes and modifications based on the following embodiments, the technical scheme claimed in the present invention can be implemented. The division of the following embodiments is for the convenience of description and should not constitute any limitation on the specific implementation of the present invention. The various embodiments can be combined and referenced with each other without contradiction.

[0046] At present, most high-precision indoor positioning systems use algorithms such as Time of Arrival (TOA) and Time Difference of Arrival (TDOA). The positioning accuracy of these algorithms strongly depends on the synchronization accuracy of base station deployment. Since radio waves propagate in the air at the speed of light, a 1ns time difference will result in a positioning accuracy difference of about 30cm. Therefore, it is very difficult to improve the indoor positioning accuracy of such systems due to the maximum operating frequency of electronic devices. Some antenna array receiving systems, such as BLE-based indoor positioning systems, use the Angle-of-Arrival (AOA) algorithm. Although it does not need to rely on base station synchronization technology to ensure positioning accuracy, it relies on the limited receiving angle resolution of the antenna array, or in order to improve the angle resolution, the receiving end needs to increase the number of antennas, which poses a considerable challenge to the portability and implementation cost of the equipment, and is not conducive to the integration of its implementation equipment in indoor mobile devices.

[0047] The indoor positioning method of the present invention can improve the accuracy of indoor positioning without increasing the difficulty of equipment deployment and use cost.

[0048] An embodiment of the present invention relates to an indoor positioning method, which is applied to an indoor positioning system. The deployment diagram of the indoor positioning system can be found in Figure 1 , which is only a schematic diagram of indoor space deployment. The actual deployment can be determined according to the actual situation. In the indoor positioning system, N LED lights are set on the indoor ceiling, N ≥ 3, Figure 1 Four LED lights and a mobile station located on the indoor floor are shown in the figure; wherein the mobile station is provided with an event camera with a lens facing the indoor ceiling, and the mobile station can be a mobile device such as an AGV car, a service robot, etc.

[0049] The implementation details of the indoor positioning method of this embodiment are described in detail below. The following content is only provided for easy understanding of the implementation details and is not necessary for implementing this solution.

[0050] The specific process of the indoor positioning method of this embodiment can be as follows: Figure 2 As shown, including:

[0051] Step 201: encode each LED lamp according to the flashing frequency of the LED lamp, and the encoded content is used to transmit the position information of each LED lamp in the indoor space.

[0052] Specifically, this embodiment controls each LED lamp to flash in a pulse modulation PWM mode, and the frequency of PWM is the flashing frequency of the LED lamp. Among them, the duty cycle of the pulse width of the PWM mode is used to indicate the relationship between the duration of each LED lamp being in a bright state and the duration of each LED lamp being in a dark state during the flashing process. At this time, each LED lamp is encoded by using characters 0 and 1 with different duty cycles.

[0053] Among them, there can be four LED lights, such as Figure 1 As shown, they are respectively arranged at the four corners of the indoor ceiling, or there are five LED lamps, four of which are respectively arranged at the four corners of the indoor ceiling, and one is arranged at the center of the indoor ceiling. If there are five LED lamps, the four LED lamps respectively arranged at the four corners of the indoor ceiling flash at the same flashing frequency, and the one LED lamp arranged at the center of the indoor ceiling flashes at a different flashing frequency from the four LED lamps respectively arranged at the four corners of the indoor ceiling.

[0054] Furthermore, when controlling each LED light to flash, each LED light can be controlled to flash in an on / off manner, or the LED light can be controlled to flash by changing the degree of brightness / dimness of the LED light. In order not to affect the lighting effect of the LED light, in actual implementation, slight changes of brightness and dimming are used to replace the direct on / off mode.

[0055] Step 202: obtain an image of N LED lights by photographing with an event camera, and capture the light intensity change of each pixel point in the image caused by the flickering of the LED lights to obtain an LED light flickering event.

[0056] Specifically, an event camera is a new type of imaging sensor inspired by biological vision. Unlike traditional cameras that collect image information at a fixed frame rate, an event camera asynchronously captures changes in light intensity on a single pixel, that is, when the light intensity change of a certain pixel exceeds a set threshold, the sensor captures the event and outputs the time when the event occurred, the pixel coordinates, and the polarity of the change (positive change or negative change). Event cameras have very attractive characteristics: high temporal resolution (microsecond level), extremely high dynamic range (140dB), low power consumption, and low latency. Therefore, event cameras have great potential in scenarios that are challenging for traditional color RGB cameras, such as high speed and complex lighting (dark light, backlight). Therefore, this embodiment captures the light intensity change of each pixel in the imaging image of N LED lights by deploying an event camera on a mobile station, so that the event camera captures the corresponding event (i.e., the flashing event of each LED light), for example, the light intensity change of a certain pixel in the imaging image of the LED light exceeds the set threshold.

[0057] Step 203: decode the coded content of each LED lamp through the obtained LED lamp flashing event to obtain the position information of each LED in the indoor space.

[0058] In the specific implementation, in step 201, when the LED light continuously flashes in accordance with the PWM mode, positive events and negative events will occur at different times on the event camera end, and the duty cycle of the pulse width in the PWM mode affects the time relationship between the positive and negative events. In this embodiment, a 20% duty cycle can be used as the character '0', and an 80% duty cycle can be used as the character '1' for encoding, that is, PWM encoding: specifically, a 200K frequency (a period of 5uS) is used as the flashing frequency of the LED light, and PWM encoding is performed on each LED light. The content of the PWM encoding will transmit the ID of the LED light, the position information x, y, z values ​​in the indoor space, and the check word. After obtaining the flashing event of each LED light, the event camera decodes the PWM encoding to obtain the position information of each LED light in the indoor space.

[0059] Among them, the content of PWM coding is as follows Figure 3 As shown, a total of 16 bytes constitute a frame of data, where ID is the number of each LED lamp, x, y, z coordinates are the position coordinates relative to the preset origin of the indoor space, in mm, and the check word is generated by the previous 14 bytes (i.e. the ID of the LED lamp and the real coordinates in the indoor space) through a cyclic redundancy check (CRC).

[0060] In one example, if each LED lamp flashes at the same PWM frequency, then the imaging images of N LED lamps are obtained by capturing the light intensity change of each pixel in the imaging image. At the same time, the event camera can obtain the flashing events of N identical LED lamps. At this time, the imaging images of the N LED lamps are divided into regions according to the connectivity and similarity of the light intensity changes of each pixel in the imaging image, and the target regions on the imaging images of the N LED lamps that simultaneously have the same flashing event are obtained. Then, the PWM code corresponding to the target region of each LED lamp on the imaging image is obtained, and the PWM code is decoded to obtain the position information of each LED lamp in the indoor space.

[0061] That is to say, since LED lights have a certain shape and according to the aforementioned LED encoding method, LED lights flash at the same frequency, the same event will occur simultaneously in the event camera imaging space. Therefore, this embodiment will perform regional division and cluster analysis based on the principles of connectivity and similarity, so as to perform regional segmentation of different LED targets. After this step is completed, the subsequent decoding process will be carried out.

[0062] In one example, an event camera will generate background activity noise due to manufacturing reasons. Specifically, when a real activity event occurs, there will also be related events in its neighborhood, and the noise mostly exists in isolation. Based on the neighborhood correlation principle, the corresponding filter is designed to remove the background activity noise before processing the imaging data.

[0063] In the specific implementation, the decoding process is divided into two steps: character recognition and information decoding: first, according to the above-mentioned divided areas, the obtained PWM code content is further abstracted into a single flashing PWM waveform, and recognized as different characters of '0' and '1' according to the duty cycle; then, according to the PWM coding rules and verification algorithm, a valid character string is decoded, and the ID and real coordinates of each different LED light in the field of view are extracted.

[0064] Step 204, projecting the physical connection line between each LED light and the event camera in the indoor space onto the two-dimensional plane where the imaging image is located, and determining the relationship between the position information of each LED light in the indoor space and the position information of the event camera in the indoor space through the horizontal angle between each LED light and the event camera on the two-dimensional plane.

[0065] Specifically, if Figure 4 As shown in the figure, the dotted line is the projection of the line connecting the three LED lights (AN1, AN2 and AN3) and the event camera on the imaging plane in the physical space. Since the projection is a two-dimensional plane, the relative angle between each LED light and the event camera can be calculated in the imaging image. (i.e. the relative angle between each of the three LED lights and the event camera and ), which is consistent with the angle between a certain LED light and the event camera in the two-dimensional plane projection. Therefore, the real spatial connection in the two-dimensional projection diagram is directly used to calculate the image. and The relationship between the position information of each LED light in the indoor space and the position information of the event camera in the indoor space is determined.

[0066] Step 205 : Acquire the position information of the mobile station in the indoor space by combining the relationship between the position information of the N LED lights in the indoor space and the position information of the event camera in the indoor space.

[0067] Specifically, see Figure 4, (x1, y1), (x2, y2), (x3, y3) are the position information of the three LED lights in the indoor space obtained by the event camera through decoding the LED flashing process, (x0, y0) is the projection coordinate of the event camera in the two-dimensional projection plane. The line connecting the coordinates (x2, y2) of LED light AN2 and the coordinates (x0, y0) of the event camera can be the following two formulas:

[0068]

[0069]

[0070] Where d represents the length of the connection between AN2 and the event camera.

[0071] Eliminating d from these two formulas yields:

[0072]

[0073] Similarly, the following formulas for the three LED lights can be obtained:

[0074] x0*sinφ1-y0*cosφ1=x1*sinφ1-y1*cosφ1

[0075] x0*sinφ2-y0*cosφ2=x2*sinφ2-y2*cosφ2

[0076] x0*sinφ3-y0*cosφ3=x3*sinφ3-y3*cosφ3

[0077] These three formulas can be listed as matrix operation formulas, and when generalized to N LED lights, the formula is as follows:

[0078] p=φ T b

[0079]

[0080] In the formula, These are the x and y coordinate values ​​of the position of the mobile station with the event camera in the indoor space to be solved.

[0081] When there are more than three LED lights, the above formula can be used to calculate the (x0, y0) coordinate value of the mobile station through the least square method. In addition, the above formula only solves the x and y coordinate values ​​of the mobile station, which is applicable to most indoor ground motion mobile station applications. For indoor drones and other aerial motion mobile stations, there is an additional Z-axis position, which can be further derived from the formula.

[0082] In this embodiment, each LED light is encoded with the flashing frequency of the LED light, and the encoded content is used to transmit the position information of each LED light in the indoor space. The imaging image of the LED light is captured by the event camera. Since the event camera can asynchronously capture the light intensity change on a single pixel on the imaging image, the light intensity change caused by the flashing of the LED light at each pixel can be obtained, and the LED light flashing event can be obtained. Then, the encoded content of each LED light can be decoded through the obtained LED light flashing event to obtain the position information of each LED in the indoor space, so as to detect the position of the subsequent mobile station in the indoor space. Among them, the imaging mechanism of the event camera is completely different from that of the traditional IS sensor. There is no time constraint for exposure by frame or row. When controlling each LED light to flash, the flashing frequency can be much higher, so that a lot of information can be carried, such as directly using the position information of the LED light in the indoor space, breaking the application of IS sensors in the field of visible light communication and visible light positioning systems caused by the delay mechanism of framed imaging. Moreover, when detecting the position of a mobile station in an indoor space, the position information of multiple LED lights in the indoor space and the horizontal angle between each LED light and the event camera on the imaging plane (i.e., the two-dimensional plane where the imaging image is located) are used. That is, it relies on the geometric relationship between the imaging points of multiple LED lights in the imaging target surface, eliminating the reliance on the synchronization accuracy between multiple base stations in the classic visible light positioning system, thereby reducing the cost and requirements of equipment deployment while ensuring indoor positioning accuracy.

[0083] In some embodiments, the indoor positioning method of the present invention can be Figure 5 It is realized by the hardware structure shown in the figure, which mainly includes distortion-free optical lens, event camera sensor, information processing subsystem and power subsystem.

[0084] Among them, the distortion-free optical lens can ensure that the angle of the X / Y coordinate position of the pixel point of the imaging geometric center of the LED in the imaging field of view is consistent with or linearly related to the angle of the line connecting the event camera field of view center to the LED geometric center in real space.

[0085] Event camera sensors can use Sony's IMX636 (resolution 1280x640, 100us delay), IMX646 (resolution 1280x720, 800us delay), PropheSee's GenX320 (resolution 320x320, 100us delay) and other similar sensors, which can generate corresponding event outputs according to the changes in light within the field of view. Each event contains coordinate information, timestamp and change attributes.

[0086] The information processing subsystem is a platform for carrying the imaging data of the event camera and calculating the algorithm running the specific coordinates of the current center of the field of view in space. As an implementation case, the minimum information processing subsystem composed of AM2732 chip, FLASH, RAM, etc. is currently used. This chip has a built-in MIPI CSI interface, which can seamlessly connect to most event camera sensors. It has a built-in dual-core ARMCortex-R5 up to 400MHz and a single-core TIDSP C66x up to 450MHz. It has powerful information processing performance and computing power, and has strong acceleration performance for various image processing algorithms. It can also use an information processing subsystem composed of high-performance multimedia processing chips such as Rockchips' RK3568.

[0087] The power subsystem is the circuit part that provides power to the above-mentioned electronic components, including event camera sensors, information processing subsystems, etc.

[0088] The step division of the various methods above is only for clear description. When implemented, they can be combined into one step or some steps can be split and decomposed into multiple steps. As long as they include the same logical relationship, they are all within the protection scope of the present invention. Adding insignificant modifications or introducing insignificant designs to the algorithm or process without changing the core design of the algorithm and process are all within the protection scope of the invention.

[0089] Another embodiment of the present invention relates to a computer device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the indoor positioning method in the above-mentioned embodiments.

[0090] Among them, the memory and the processor are connected in a bus manner, and the bus may include any number of interconnected buses and bridges, and the bus connects various circuits of one or more processors and memories together. The bus can also connect various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. The bus interface provides an interface between the bus and the transceiver. The transceiver can be one element or multiple elements, such as multiple receivers and transmitters, providing a unit for communicating with various other devices on a transmission medium. The data processed by the processor is transmitted on a wireless medium via an antenna, and further, the antenna also receives data and transmits the data to the processor.

[0091] The processor is responsible for managing the bus and general processing, and can also provide various functions, including timing, peripheral interfaces, voltage regulation, power management, and other control functions. Memory can be used to store data used by the processor when performing operations.

[0092] Another embodiment of the present invention relates to a computer-readable storage medium storing a computer program, which implements the above method embodiment when executed by a processor.

[0093] That is, those skilled in the art can understand that all or part of the steps in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a program, and the program is stored in a storage medium, including a number of instructions for a device (which can be a single-chip microcomputer, chip, etc.) or a processor (processor) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, referred to as: ROM), random access memory (Random Access Memory, referred to as: RAM), disk or optical disk and other media that can store program codes.

[0094] Those skilled in the art will appreciate that the above embodiments are specific embodiments for implementing the present invention, and in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present invention.

Claims

1. An indoor positioning method, characterized in that: Applied to an indoor positioning system, the indoor positioning system comprises: N LED lights arranged on an indoor ceiling and a mobile station located on the indoor floor, the mobile station is provided with an event camera with a lens facing the indoor ceiling, N≥3; The method comprises: Each LED lamp is encoded according to the flashing frequency of the LED lamp, and the encoded content is used to transmit the position information of each LED lamp in the indoor space; The imaging images of N LED lights are obtained by shooting with an event camera, and the light intensity change of each pixel point in the imaging image caused by the LED light flickering is captured to obtain the LED light flickering event; By obtaining the LED light flashing events, the coded content of each LED light is decoded to obtain the position information of each LED in the indoor space; The physical connection line between each LED light and the event camera in the indoor space is projected onto the two-dimensional plane where the imaging image is located, and the relationship between the position information of each LED light in the indoor space and the position information of the event camera in the indoor space is determined by the angle between each LED light and the event camera in the horizontal direction on the two-dimensional plane; The position information of the mobile station in the indoor space is obtained by combining the relationship between the position information of the N LED lights in the indoor space and the position information of the event camera in the indoor space.

2. The indoor positioning method according to claim 1, characterized in that: The flashing frequencies of the N LED lamps are the same, and the encoded content of each LED lamp is decoded by the obtained LED lamp flashing event to obtain the position information of each LED in the indoor space, including: Get multiple identical LED light flashing events at the same time; According to the connectivity and similarity between the light intensity changes of each pixel in multiple identical LED light flashing events, the imaging images of N LED lights are divided into regions to obtain the target regions of the N LED lights on the imaging images; The code of the LED light corresponding to each target area on the imaging image is obtained, and the position information of each LED light in the indoor space is obtained by decoding.

3. The indoor positioning method according to claim 2, characterized in that: The step of encoding each LED lamp according to the flashing frequency of the LED lamp comprises: Control each LED light to flash in a pulse modulation PWM mode, where the frequency of PWM is the flashing frequency of the LED light; wherein the duty cycle of the pulse width of the PWM mode is used to indicate the relationship between the duration of each LED light being in a bright state and the duration of each LED light being in a dark state during the flashing process; Each LED light is encoded by using character 0 and character 1 with different duty cycles.

4. The indoor positioning method according to claim 3, characterized in that: The decoding of the coded content of each LED lamp to obtain the position information of each LED in the indoor space includes: The obtained coded content is abstracted into a single flashing PWM waveform, and the characters 0 and 1 are identified according to the duty cycle to decode and obtain the position information of each LED in the indoor space.

5. The indoor positioning method according to claim 1, characterized in that: The relationship between the position information of each LED light in the indoor space and the position information of the event camera in the indoor space is expressed by the following formula: Where (x0, y0) represents the location information of the mobile station in the indoor space, (x1, y1),..., (x N ,y N ) represents the position information of N LED lights in the indoor space. They respectively represent the horizontal angles between the N LED lights and the event camera on the two-dimensional plane.

6. The indoor positioning method according to claim 5, characterized in that: The step of combining the relationship between the position information of the N LED lights in the indoor space and the position information of the event camera in the indoor space to obtain the position information of the mobile station in the indoor space includes: The location information of the mobile station in the indoor space is obtained by the following formula: p=φ T b Where p represents the location information (x0, y0) of the mobile station in the indoor space, and b is the intermediate value.

7. The indoor positioning method according to claim 1, characterized in that: There are four LED lamps, which are respectively arranged at the four corners of the indoor ceiling; or there are five LED lamps, four of which are respectively arranged at the four corners of the indoor ceiling, and one is arranged at the center of the indoor ceiling. Among them, if there are five LED lamps, the four LED lamps respectively arranged at the four corners of the indoor ceiling flash at the same flashing frequency, and the one LED lamp arranged at the center of the indoor ceiling flashes at a flashing frequency different from that of the four LED lamps respectively arranged at the four corners of the indoor ceiling.

8. The indoor positioning method according to claim 1, characterized in that: Each of the LED lights flashes in an on / off manner, or the LED lights flash by changing the degree of brightness / dimness of the LED lights.

9. A computer device, characterized in that: include: at least one processor; And, a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the indoor positioning method as described in any one of claims 1 to 8.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the indoor positioning method according to any one of claims 1 to 8 is implemented.

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