AGV positioning method and system based on optical communication

Abstract

The present disclosure relates to an AGV positioning method and system based on optical communication, which can achieve direction and distance measurement for the AGV by switching pulses at different time angles, thereby reducing the positioning cost of the AGV. The method includes: receiving near-infrared positioning pulses through the AGV's optical communication module, wherein the near-infrared positioning pulses have different emission angles; determining the time difference positioning result of the AGV based on the pulse time difference, light speed, and correction model of the near-infrared positioning pulses emitted by the target optical communication terminal; and determining the intensity ranging result of the AGV based on the pulse intensity of the near-infrared positioning pulses and the distance attenuation model; and obtaining the target positioning result of the AGV based on the time difference positioning result and the intensity ranging result.

Description

Technical Field

[0001] The present disclosure relates to the field of optical communication technology, and in particular to an AGV positioning method and system based on optical communication. Background Art

[0002] An AGV, or automated guided vehicle, is a type of transport equipment that can autonomously travel along a pre-set route. Relying on electromagnetic and optical automatic guidance devices, it requires no operator intervention. It is commonly used in industrial production, logistics, and warehousing, enabling material handling and cargo distribution. This improves production and logistics efficiency, reduces labor costs, and ensures accurate and stable transportation. For example, in automobile manufacturing plants, AGVs can precisely deliver parts to the corresponding production line locations along a pre-set route. In e-commerce warehouses, they can navigate between shelves, picking and moving goods.

[0003] In related technologies, magnetic strips or QR codes are usually laid on the ground, and AGVs use sensors to read path information. Because magnetic strips are laid on the ground, they are easily crushed and deformed, and QR codes are easily stained or faded, resulting in high maintenance costs. Summary of the Invention

[0004] In order to overcome the problems existing in the related art, the embodiments of the present disclosure provide an AGV positioning method and system based on optical communication to solve the defects in the related art.

[0005] According to a first aspect of an embodiment of the present disclosure, a method for positioning an AGV based on optical communication is provided, comprising:

[0006] The optical communication module of the AGV receives near-infrared positioning pulses, which are emitted by a fixed target optical communication terminal in the cargo area activated by the warehouse control system. The target optical communication terminal is closest to the target cargo area where the AGV performs its task, and the emission angle of the near-infrared positioning pulses emitted by the target optical communication terminal is different;

[0007] Determine the time difference positioning result of the AGV according to the pulse time difference, light speed and correction model of the near-infrared positioning pulse emitted by the target optical communication terminal, and determine the intensity ranging result of the AGV according to the pulse intensity and distance attenuation model of the near-infrared positioning pulse;

[0008] The target positioning result of the AGV is obtained according to the time difference positioning result and the intensity ranging result.

[0009] In one embodiment, the target optical communication end includes a first optical communication end and a second optical communication end, the near-infrared positioning pulse includes a first near-infrared positioning pulse emitted by the first optical communication end and a second near-infrared positioning pulse emitted by the second optical communication end, and the emission angle range of the first near-infrared positioning pulse is smaller than the emission angle range of the second near-infrared positioning pulse.

[0010] In one embodiment, the near-infrared positioning pulse is emitted by the warehouse control system by activating a fixed target optical communication terminal in the target cargo area in the following manner:

[0011] Receiving task data carrying cargo location coordinates sent by a warehouse management system, wherein the horizontal coordinate and the vertical coordinate in the cargo location coordinate are encrypted using different encryption keys;

[0012] Decrypting the horizontal coordinate and the vertical coordinate in the task data using a decryption key corresponding to the encryption key to obtain the cargo location coordinates, and determining the target cargo location based on the cargo location coordinates;

[0013] The target optical communication terminal fixed in the cargo area and closest to the target cargo location is activated to emit a near-infrared positioning pulse.

[0014] In one embodiment, the target optical communication end includes a first optical communication end and a second optical communication end, and determining the time difference positioning result of the AGV according to the pulse time difference, light speed and correction model of the near-infrared positioning pulse emitted by the target optical communication end includes:

[0015] Determine a first arrival time of the near-infrared positioning pulse emitted by the first optical communication end and a second arrival time of the near-infrared positioning pulse emitted by the second optical communication end, and correct the time difference between the first arrival time and the second arrival time to determine it as the pulse time difference;

[0016] determining the product of the pulse time difference and the speed of light as the distance difference;

[0017] The distance difference, the position coordinates of the first optical communication end, and the position coordinates of the second optical communication end are substituted into the correction model to obtain the time difference positioning result of the AGV vehicle, wherein the correction model represents that the first distance between the position coordinates of the AGV vehicle and the position coordinates of the first optical communication end minus the second distance between the position coordinates of the AGV vehicle and the position coordinates of the second optical communication end is equal to the distance difference.

[0018] In one embodiment, the maximum distance of optical communication between the target optical communication terminal and the AGV is a third distance, and the intensity ranging result of the AGV is determined according to the pulse intensity and distance attenuation model of the near-infrared positioning pulse, including:

[0019] Dividing the first difference by the second difference as the pulse intensity of the near-infrared positioning pulse, wherein the first difference is obtained by subtracting the ambient light noise voltage value from the voltage value of the near-infrared positioning pulse, and the second difference is obtained by subtracting the ambient light noise voltage value from the pre-stored maximum voltage value;

[0020] The pulse intensity is substituted into the distance attenuation model to obtain the intensity ranging result of the AGV vehicle, wherein the distance attenuation model characterizes that the intensity ranging result of the AGV vehicle is equal to the third distance multiplied by the target difference, and the target difference is obtained by subtracting the pulse intensity from 1.

[0021] In one embodiment, obtaining the target positioning result of the AGV according to the time difference positioning result and the intensity ranging result includes:

[0022] The time difference positioning result is used as a priori estimation and the intensity ranging result is used as an observation constraint, and the target positioning result of the AGV vehicle is obtained through the Kalman filter algorithm.

[0023] In one embodiment, the AGV positioning method based on optical communication further includes:

[0024] In the process of the AGV moving to the target cargo location based on the target positioning result, the optical communication module receives a new near-infrared positioning pulse emitted by the target optical communication terminal at every preset time interval;

[0025] The target positioning result of the AGV is updated according to the new near-infrared positioning pulse emitted by the target optical communication terminal.

[0026] In one embodiment, the AGV positioning method based on optical communication further includes:

[0027] When the distance between the AGV and the target cargo location is less than a preset distance, receiving a narrow-angle pulse sequence and a wide-angle pulse sequence transmitted by the target optical communication terminal, wherein the transmission angle range of the narrow-angle pulse sequence is smaller than the transmission angle range of the wide-angle pulse sequence;

[0028] When the pulse intensities on the left and right sides of the narrow-angle pulse sequence are asymmetric, the AGV is controlled to adjust its posture so that the pulse intensities on the left and right sides of the narrow-angle pulse sequence received by the AGV are symmetrical, and when the pulse intensity of the wide-angle pulse sequence reaches a first preset intensity threshold, the moving speed of the AGV is reduced to a preset speed until the pulse intensity of the wide-angle pulse sequence reaches a second preset intensity threshold, and the AGV is controlled to stop moving, wherein the first preset intensity threshold is less than the second preset intensity threshold.

[0029] According to a second aspect of an embodiment of the present disclosure, there is provided an AGV positioning system based on optical communication, comprising a warehouse management system, a warehouse control system, a plurality of optical communication terminals fixed in a cargo area, and an AGV including an optical communication module;

[0030] The warehouse management system is used to send task data carrying cargo location coordinates to the warehouse control system;

[0031] The warehouse control system is used to determine the target cargo location according to the cargo location coordinates, and activate the target optical communication terminal closest to the target cargo location in the cargo location area to transmit near-infrared positioning pulses to the AGV;

[0032] The AGV is used to execute any of the optical communication-based AGV positioning methods described in the first aspect.

[0033] According to a third aspect of an embodiment of the present disclosure, an AGV is provided, comprising an optical communication module, a memory and a processor, wherein the memory is used to store computer instructions that can be executed on the processor, and the processor is used to implement the steps of any method described in the first aspect when executing the computer instructions.

[0034] The technical solutions provided by the embodiments of the present disclosure may have the following beneficial effects:

[0035] The AGV trolley positioning method provided by the embodiment of the present disclosure can receive near-infrared positioning pulses through the optical communication module of the AGV trolley, and then obtain the target positioning result of the AGV trolley based on the near-infrared positioning pulses. In this way, the positioning of the AGV trolley based on optical communication can be achieved. Compared with the method of laying magnetic strips or QR code labels on the ground, it can reduce maintenance costs, improve the positioning accuracy of the AGV trolley, and can be used in confidential working conditions. In addition, the emission angles of the near-infrared positioning pulses emitted by the fixed target optical communication terminal in the cargo area are different, so the communication channel can be multiplexed, and the direction and distance measurement of the AGV trolley can be achieved by time-sharing angle switching pulses, thereby further reducing the positioning cost of the AGV trolley. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0037] Figure 1 This is a flow chart of an AGV positioning method based on optical communication according to an exemplary embodiment of the present disclosure;

[0038] Figure 2 FIG1 is a diagram showing a task execution architecture of an AGV vehicle according to an exemplary embodiment of the present disclosure;

[0039] Figure 3 This is a task execution flow chart of an AGV vehicle shown in an exemplary embodiment of the present disclosure;

[0040] Figure 4 It is a structural block diagram of an AGV vehicle shown in an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0041] Exemplary embodiments are described in detail herein, with examples illustrated in the accompanying drawings. When the following description refers to the drawings, identical numerals in different drawings represent identical or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present disclosure.

[0042] The terms used in this disclosure are for the purpose of describing specific embodiments only and are not intended to limit the disclosure. The singular forms "a," "the," and "the" used in this disclosure are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0043] It should be understood that although the terms "first," "second," and "third" may be used in this disclosure to describe various types of information, such information should not be limited to these terms. These terms are merely used to distinguish information of the same type from one another. For example, without departing from the scope of this disclosure, first information may also be referred to as second information, and similarly, second information may also be referred to as first information.

[0044] In a first aspect, at least one embodiment of the present disclosure provides an AGV positioning method based on optical communication.

[0045] First, it's important to understand that optical communication sensors primarily replace conventional point-to-point cable communication. They use infrared light as a data carrier to transmit communication data, I / O signals, and other information from end A to end B for output. The fixed transmission range of infrared light allows signal transmission to be controlled within a limited range, making it suitable for use in confidentiality situations. The basic operating principle of optical communication sensors is bidirectional data transmission via modulated light. In the transmitter circuit, data is encoded using pulse-width modulation, converted into an optical carrier signal, and transmitted to the receiver. In the receiver circuit, the data is demodulated and output. Using a dedicated communication protocol, they offer excellent interference resistance and higher reliability than transparent output methods.

[0046] Please refer to the attached Figure 1 , which shows the process of the method, including steps S101 to S103.

[0047] In step S101, the optical communication module of the AGV receives a near-infrared positioning pulse, which is emitted by a fixed target optical communication terminal in the cargo area activated by the warehouse control system. The target optical communication terminal is closest to the target cargo area where the AGV performs the task, and the emission angle of the near-infrared positioning pulse emitted by the target optical communication terminal is different.

[0048] In step S102, the time difference positioning result of the AGV is determined based on the pulse time difference, light speed and correction model of the near-infrared positioning pulse emitted by the target optical communication terminal, and the intensity ranging result of the AGV is determined based on the pulse intensity and distance attenuation model of the near-infrared positioning pulse.

[0049] It should be understood that the time difference positioning result of the AGV car can be determined first, and then the strength ranging result of the AGV car can be determined, or the strength ranging result of the AGV car can be determined first, and then the time difference positioning result of the AGV car can be determined, or the time difference positioning result and the strength ranging result of the AGV car can be determined at the same time. The present disclosure does not limit this.

[0050] In step S103, the target positioning result of the AGV is obtained according to the time difference positioning result and the intensity ranging result.

[0051] Thus, the optical communication module of the AGV can receive near-infrared positioning pulses, and then the target positioning result of the AGV can be obtained based on the near-infrared positioning pulses. In this way, the positioning of the AGV can be realized based on optical communication. Compared with the method of laying magnetic strips or QR code labels on the ground, it can reduce maintenance costs, improve the positioning accuracy of the AGV, and can be used in confidential working conditions. In addition, the emission angles of the near-infrared positioning pulses emitted by the fixed target optical communication terminal in the cargo area are different, so the communication channel can be reused, and the direction and distance of the AGV can be achieved by switching the pulses at different angles, thereby further reducing and increasing the positioning cost of the AGV.

[0052] In order to facilitate understanding of the AGV positioning method based on optical communication provided by the present disclosure, the above steps are further explained below.

[0053] In one embodiment, the near-infrared positioning pulse is emitted by the warehouse control system by activating a fixed target optical communication terminal in the target cargo area in the following manner:

[0054] Receiving task data carrying cargo location coordinates sent by a warehouse management system, wherein the horizontal coordinate and the vertical coordinate in the cargo location coordinate are encrypted using different encryption keys;

[0055] Decrypting the horizontal coordinate and the vertical coordinate in the task data using a decryption key corresponding to the encryption key to obtain the cargo location coordinates, and determining the target cargo location based on the cargo location coordinates;

[0056] The target optical communication terminal fixed in the cargo area and closest to the target cargo location is activated to emit a near-infrared positioning pulse.

[0057] For example, a warehouse management system (WMS) sends location coordinates (such as grid coordinates or relative reference point positions) as part of a task. However, these coordinates are stored in a fragmented, encrypted format (which can only be parsed by the warehouse control system (WCS)). The WCS decrypts the location coordinates and determines the target location based on them. It then controls the optical communication terminal (e.g., terminal A) in the storage area closest to the target location to enter positioning mode, emitting near-infrared positioning pulses (different from communication pulses, which have a higher frequency). These pulses are time-shifted at specific angles: ±5°, ±10°, and ±15°.

[0058] In one embodiment, the target optical communication end includes a first optical communication end and a second optical communication end, the near-infrared positioning pulse includes a first near-infrared positioning pulse emitted by the first optical communication end and a second near-infrared positioning pulse emitted by the second optical communication end, and the emission angle range of the first near-infrared positioning pulse is smaller than the emission angle range of the second near-infrared positioning pulse.

[0059] For example, the WCS receives a WMS command instructing an AGV to proceed to the location coordinates (X5, Y3) to retrieve BOX-20. The WCS interprets the coordinates and activates the two closest fixed optical communication terminals (i.e., target optical communication terminals) to that location. These two fixed optical communication terminals enter positioning mode and emit near-infrared positioning pulses (separate from communication pulses) according to the following timing sequence: t = 0ms: The first optical communication terminal emits a ±5° narrow-angle pulse (frequency 1kHz, duration 5ms); t = 10ms: The second optical communication terminal emits a ±15° wide-angle pulse (frequency 500Hz, duration 10ms). This achieves directional coverage through time-sharing angle switching, reducing the AGV's positioning costs.

[0060] In one embodiment, the target optical communication end includes a first optical communication end and a second optical communication end, and determining the time difference positioning result of the AGV according to the pulse time difference, light speed and correction model of the near-infrared positioning pulse emitted by the target optical communication end includes:

[0061] Determine a first arrival time of the near-infrared positioning pulse emitted by the first optical communication end and a second arrival time of the near-infrared positioning pulse emitted by the second optical communication end, and determine a time difference between the first arrival time and the second arrival time as a pulse time difference;

[0062] determining the product of the pulse time difference and the speed of light as the distance difference;

[0063] The distance difference, the position coordinates of the first optical communication end, and the position coordinates of the second optical communication end are substituted into the correction model to obtain the time difference positioning result of the AGV vehicle, wherein the correction model represents that the first distance between the position coordinates of the AGV vehicle and the position coordinates of the first optical communication end minus the second distance between the position coordinates of the AGV vehicle and the position coordinates of the second optical communication end is equal to the distance difference.

[0064] For example, continuing with the above example, the first optical communication terminal in the cargo area transmits ±5° near-infrared positioning pulses (strong directionality), the second optical communication terminal transmits ±15° near-infrared positioning pulses (large coverage), and the position coordinates of the first optical communication terminal are ( , ), the position coordinates of the second optical communication end are ( , ). The optical communication module of the AGV records the first arrival time t1 = 2.1ms and the second arrival time t2 = 3.0ms, calculates the time difference Δt = |t1 - t2| = 0.9ms, and corrects the time difference according to the preset correction parameter to obtain a pulse time difference of 0.9ns. The preset correction coefficient can be obtained through experiments, for example, it can be set to Distance difference Δd = c × Δt = 3×10 8 × 0.9× = 0.27 m. Substitute the distance difference Δd, the position coordinates of the first optical communication end (x1, y1), and the position coordinates of the second optical communication end (x2, y2) into the correction model to obtain the position coordinates (x, y) of the AGV.

[0065] In one embodiment, the maximum distance of optical communication between the target optical communication terminal and the AGV is a third distance, and the intensity ranging result of the AGV is determined according to the pulse intensity and distance attenuation model of the near-infrared positioning pulse, including:

[0066] The result of dividing the first difference by the second difference is used as the pulse intensity of the near-infrared positioning pulse, wherein the first difference is obtained by subtracting the ambient light noise voltage value from the voltage value of the near-infrared positioning pulse, and the second difference is obtained by subtracting the ambient light noise voltage value from the pre-stored maximum voltage value. The pre-stored maximum voltage value is the voltage value measured at zero distance from the transmitter surface of the optical communication end.

[0067] The pulse intensity is substituted into the distance attenuation model to obtain the intensity ranging result of the AGV vehicle, wherein the distance attenuation model characterizes that the intensity ranging result of the AGV vehicle is equal to the third distance multiplied by the target difference, and the target difference is obtained by subtracting the pulse intensity from 1.

[0068] For example, continuing with the above example, the pulse intensity of the ±15° near-infrared positioning pulse received by the AGV is measured. The voltage value of the ±15° near-infrared positioning pulse measured by the AGV is 2.4V, the ambient noise voltage is 0.3V, and the pre-stored maximum voltage at 0 distance is 3V. Therefore, the pulse intensity is approximately 78%. This pulse intensity is then substituted into the distance attenuation model to obtain the intensity ranging result of the AGV. For example, if the third distance is 2m, the intensity ranging result of the AGV is 0.44m.

[0069] It should be understood that the percentage pulse strength is the result of hardware measurement value plus dynamic normalization, which not only ensures the near-field positioning accuracy (for example, within 2 meters), but also realizes physical layer encryption through device-dependent parameters (such as pre-stored maximum voltage value), which can better adapt to the needs of confidential places.

[0070] In one embodiment, obtaining the target positioning result of the AGV according to the time difference positioning result and the intensity ranging result includes:

[0071] The time difference positioning result is used as a priori estimation and the intensity ranging result is used as an observation constraint, and the target positioning result of the AGV vehicle is obtained through the Kalman filter algorithm.

[0072] Therefore, by integrating time difference positioning (i.e., global low precision) and intensity ranging (i.e., local high precision) through Kalman filtering, it is possible to output target positioning results with smaller errors and meet the confidentiality requirements of confidential places throughout the process.

[0073] In one embodiment, the AGV positioning method based on optical communication further includes:

[0074] In the process of the AGV moving to the target cargo location based on the target positioning result, the optical communication module receives a new near-infrared positioning pulse emitted by the target optical communication terminal at every preset time interval;

[0075] The target positioning result of the AGV is updated according to the new near-infrared positioning pulse emitted by the target optical communication terminal.

[0076] For example, continuing with the above example, while the AGV is moving, the first and second optical communication terminals emit new near-infrared positioning pulses at a 200ms period. The AGV can then re-determine its positioning results based on these new near-infrared positioning pulses, using the aforementioned method. This allows for periodic calibration of positioning results during the AGV's movement, improving its positioning accuracy.

[0077] In one embodiment, the AGV positioning method based on optical communication further includes:

[0078] When the distance between the AGV and the target cargo location is less than a preset distance, receiving a narrow-angle pulse sequence and a wide-angle pulse sequence transmitted by the target optical communication terminal, wherein the transmission angle range of the narrow-angle pulse sequence is smaller than the transmission angle range of the wide-angle pulse sequence;

[0079] When the pulse intensities on the left and right sides of the narrow-angle pulse sequence are asymmetric, the AGV is controlled to adjust its posture so that the pulse intensities on the left and right sides of the narrow-angle pulse sequence received by the AGV are symmetrical, and when the pulse intensity of the wide-angle pulse sequence reaches a first preset intensity threshold, the moving speed of the AGV is reduced to a preset speed until the pulse intensity of the wide-angle pulse sequence reaches a second preset intensity threshold, and the AGV is controlled to stop moving, wherein the first preset intensity threshold is less than the second preset intensity threshold.

[0080] For example, continuing with the above example, the AGV is 0.5m from the target location, less than the preset distance of 0.6m. It receives a ±5° narrow-angle pulse from the first optical communication terminal, with the left pulse intensity at 85% and the right pulse intensity at 15%, resulting in asymmetric pulse intensities on the left and right sides. The AGV then rotates 3° counterclockwise until the pulses are symmetrical (i.e., the left and right pulse intensities are both approximately 50%). Furthermore, the AGV detects that the ±15° wide-angle pulse intensity from the second optical communication terminal reaches 95%. The AGV approaches the target location at a low speed of 0.1m / s until the intensity reaches ≥98%, confirming that it is ready to dock. This allows the AGV to maintain a positional error of less than 2cm relative to the target location. The AGV can then use its robotic arm to retrieve the bin, completing the pickup.

[0081] It should be understood that the basic parameters of optical communication in this disclosure are as follows:

[0082] Communication carrier: near infrared

[0083] Debugging method: pulse modulation

[0084] Communication mode: full duplex or half duplex

[0085] Communication delay: 15-20ms

[0086] Optical communication establishment time: 25ms

[0087] Working distance: up to 2 meters

[0088] It should also be understood that the AGV positioning method disclosed herein is applied to the process of the AGV performing a task (such as a pickup task). Figure 2 and Figure 3 , the AGV car's picking task process includes:

[0089] 1. WMS issues the task ID and material box number;

[0090] 2. WCS receives the task;

[0091] 3. The WCS parses the task and sends it to the AGV via optical communication.

[0092] 4. The AGV receives the pickup task through the optical communication fixed terminal;

[0093] 5. The AGV performs the task of picking up goods;

[0094] 6. The AGV responds with a response to complete the loading task;

[0095] 7. WCS receives execution completion.

[0096] According to a second aspect of an embodiment of the present disclosure, there is provided an AGV positioning system based on optical communication, comprising a warehouse management system, a warehouse control system, a plurality of optical communication terminals fixed in a cargo area, and an AGV including an optical communication module;

[0097] The warehouse management system is used to send task data carrying cargo location coordinates to the warehouse control system;

[0098] The warehouse control system is used to determine the target cargo location according to the cargo location coordinates, and activate the target optical communication terminal closest to the target cargo location in the cargo location area to transmit near-infrared positioning pulses to the AGV;

[0099] The AGV is used to execute any of the above-mentioned AGV positioning methods based on optical communication.

[0100] According to the third aspect of an embodiment of the present disclosure, an AGV is provided, comprising an optical communication module, a memory and a processor, wherein the memory is used to store computer instructions that can be run on the processor, and the processor is used to implement the steps of any of the above-mentioned methods when executing the computer instructions.

[0101] Please refer to the attached Figure 4 , which exemplarily shows a block diagram of an AGV, the AGV 700 may include: a processor 701, a memory 702. The AGV 700 may also include one or more of a multimedia component 703, an input / output (I / O) interface 704, and a communication component 705.

[0102] The processor 701 is used to control the overall operation of the AGV 700 to complete all or part of the steps in any of the above-mentioned methods. The memory 702 is used to store various types of data to support the operation of the AGV 700. This data may include, for example, instructions for any application or method operating on the AGV 700, as well as application-related data, such as target positioning results. The memory 702 can be implemented by any type of volatile or non-volatile storage device, or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The multimedia component 703 may include a screen and an audio component. The screen may be, for example, a touch screen, and the audio component is used to output and / or input audio signals. For example, the audio component may include a microphone for receiving external audio signals. The received audio signal may be further stored in the memory 702 or sent through the communication component 705. The audio component also includes at least one speaker for outputting audio signals. The I / O interface 704 provides an interface between the processor 701 and other interface modules. The above-mentioned other interface modules may be a keyboard, a mouse, buttons, etc. These buttons may be virtual buttons or physical buttons. The communication component 705 is used for wired or wireless communication between the AGV 700 and other devices. Wireless communication, such as optical communication, Wi-Fi, Bluetooth, Near Field Communication (NFC), 2G, 3G or 4G, or a combination of one or more of them, so the corresponding communication component 705 may include: an optical communication module, a Wi-Fi module, a Bluetooth module, an NFC module.

[0103] In an exemplary embodiment, the AGV 700 can be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components to perform the above-mentioned positioning method.

[0104] In another exemplary embodiment, a computer-readable storage medium including program instructions is further provided. When the program instructions are executed by a processor, the steps of any of the above methods are implemented. For example, the computer-readable storage medium may be the memory 702 including the program instructions. The program instructions may be executed by the processor 701 of the AGV 700 to implement any of the above methods.

[0105] In another exemplary embodiment, a computer program product is further provided. The computer program product includes a computer program that can be executed by a processor. When the computer program is executed by the processor, the steps of any of the above methods are implemented.

[0106] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings. However, the present disclosure is not limited to the specific details of the above embodiments. Within the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the scope of protection of the present disclosure.

[0107] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0108] In addition, the various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. An AGV positioning method based on optical communication, characterized in that: include: The optical communication module of the AGV receives near-infrared positioning pulses, which are emitted by a fixed target optical communication terminal in the cargo area activated by the warehouse control system. The target optical communication terminal is closest to the target cargo area where the AGV performs its task, and the emission angle of the near-infrared positioning pulses emitted by the target optical communication terminal is different; Determine the time difference positioning result of the AGV according to the pulse time difference, light speed and correction model of the near-infrared positioning pulse emitted by the target optical communication terminal, and determine the intensity ranging result of the AGV according to the pulse intensity and distance attenuation model of the near-infrared positioning pulse; Obtaining the target positioning result of the AGV according to the time difference positioning result and the intensity ranging result; The target optical communication end includes a first optical communication end and a second optical communication end, and determining the time difference positioning result of the AGV according to the pulse time difference, light speed and correction model of the near-infrared positioning pulse emitted by the target optical communication end includes: Determine a first arrival time of the near-infrared positioning pulse emitted by the first optical communication end and a second arrival time of the near-infrared positioning pulse emitted by the second optical communication end, and correct the time difference between the first arrival time and the second arrival time to determine it as the pulse time difference; determining the product of the pulse time difference and the speed of light as the distance difference; The distance difference, the position coordinates of the first optical communication end, and the position coordinates of the second optical communication end are substituted into the correction model to obtain the time difference positioning result of the AGV vehicle, wherein the correction model represents that the first distance between the position coordinates of the AGV vehicle and the position coordinates of the first optical communication end minus the second distance between the position coordinates of the AGV vehicle and the position coordinates of the second optical communication end is equal to the distance difference.

2. The AGV positioning method based on optical communication according to claim 1 is characterized in that: The target optical communication end includes a first optical communication end and a second optical communication end, the near-infrared positioning pulse includes a first near-infrared positioning pulse emitted by the first optical communication end and a second near-infrared positioning pulse emitted by the second optical communication end, and the emission angle range of the first near-infrared positioning pulse is smaller than the emission angle range of the second near-infrared positioning pulse.

3. The AGV positioning method based on optical communication according to claim 1, characterized in that: The near-infrared positioning pulse is emitted by the warehouse control system by activating a fixed target optical communication terminal in the target cargo area in the following manner: Receiving task data carrying cargo location coordinates sent by a warehouse management system, wherein the horizontal coordinate and the vertical coordinate in the cargo location coordinate are encrypted using different encryption keys; Decrypting the horizontal coordinate and the vertical coordinate in the task data using a decryption key corresponding to the encryption key to obtain the cargo location coordinates, and determining the target cargo location based on the cargo location coordinates; The target optical communication terminal fixed in the cargo area and closest to the target cargo location is activated to emit a near-infrared positioning pulse.

4. The AGV positioning method based on optical communication according to claim 1, characterized in that: The maximum distance of optical communication between the target optical communication terminal and the AGV is a third distance, and the intensity ranging result of the AGV is determined according to the pulse intensity and distance attenuation model of the near-infrared positioning pulse, including: Dividing the first difference by the second difference as the pulse intensity of the near-infrared positioning pulse, wherein the first difference is obtained by subtracting the ambient light noise voltage value from the voltage value of the near-infrared positioning pulse, and the second difference is obtained by subtracting the ambient light noise voltage value from the pre-stored maximum voltage value; The pulse intensity is substituted into the distance attenuation model to obtain the intensity ranging result of the AGV vehicle, wherein the distance attenuation model characterizes that the intensity ranging result of the AGV vehicle is equal to the third distance multiplied by the target difference, and the target difference is obtained by subtracting the pulse intensity from 1.

5. The AGV positioning method based on optical communication according to claim 1, characterized in that: Obtaining the target positioning result of the AGV according to the time difference positioning result and the intensity ranging result includes: The time difference positioning result is used as a priori estimation and the intensity ranging result is used as an observation constraint, and the target positioning result of the AGV vehicle is obtained through the Kalman filter algorithm.

6. The AGV positioning method based on optical communication according to claim 1, characterized in that: The AGV positioning method based on optical communication also includes: In the process of the AGV moving to the target cargo location based on the target positioning result, the optical communication module receives a new near-infrared positioning pulse emitted by the target optical communication terminal at every preset time interval; The target positioning result of the AGV is updated according to the new near-infrared positioning pulse emitted by the target optical communication terminal.

7. The AGV positioning method based on optical communication according to claim 6, characterized in that: The AGV positioning method based on optical communication also includes: When the distance between the AGV and the target cargo location is less than a preset distance, receiving a narrow-angle pulse sequence and a wide-angle pulse sequence transmitted by the target optical communication terminal, wherein the transmission angle range of the narrow-angle pulse sequence is smaller than the transmission angle range of the wide-angle pulse sequence; When the pulse intensities on the left and right sides of the narrow-angle pulse sequence are asymmetric, the AGV is controlled to adjust its posture so that the pulse intensities on the left and right sides of the narrow-angle pulse sequence received by the AGV are symmetrical, and when the pulse intensity of the wide-angle pulse sequence reaches a first preset intensity threshold, the moving speed of the AGV is reduced to a preset speed until the pulse intensity of the wide-angle pulse sequence reaches a second preset intensity threshold, and the AGV is controlled to stop moving, wherein the first preset intensity threshold is less than the second preset intensity threshold.

8. An AGV positioning system based on optical communication, characterized in that: It includes a warehouse management system, a warehouse control system, multiple optical communication terminals fixed in the cargo area, and an AGV car including an optical communication module; The warehouse management system is used to send task data carrying cargo location coordinates to the warehouse control system; The warehouse control system is used to determine the target cargo location according to the cargo location coordinates, and activate the target optical communication terminal closest to the target cargo location in the cargo location area to transmit near-infrared positioning pulses to the AGV; The AGV trolley is used to execute the AGV trolley positioning method based on optical communication according to any one of claims 1 to 7.

9. An AGV car, characterized in that: The optical communication device comprises an optical communication module, a memory and a processor, wherein the memory is used to store computer instructions that can be run on the processor, and the processor is used to implement the steps of the method according to any one of claims 1 to 7 when executing the computer instructions.

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