Infrared induction automatic broadcasting exhibition device and method

Abstract

The invention relates to the technical field of exhibition display, in particular to an infrared induction automatic broadcasting exhibition device and method, and the device comprises a main control module, an infrared induction module, a voice broadcasting module, a storage module and a power management module. The infrared induction module adopts a modulation type sensor, and is combined with a multi-mode anti-interference algorithm (through finite-state machine logic of cooperation of trigger delay and departure delay) of the main control module to filter ambient light and instantaneous interference and accurately identify entering, staying and departure states of visitors; the positioning precision is improved through multi-sensor partition cooperation, and the voice broadcast module is controlled to play audios to realize non-inductive triggering and directional broadcasting. The system is high in anti-interference capability, low in power consumption standby when no audience exists, capable of reducing cost, suitable for places such as museums and art museums and capable of achieving upgrading from the toy level to the commercial level.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of exhibition display, in particular to an infrared induction automatic voice broadcast exhibition device and method. BACKGROUND

[0002] In museum, art gallery, science and technology museum, enterprise exhibition hall and memorial hall and other exhibition places, the traditional voice guide mode mainly has three kinds: the first is artificial explanation, which mainly depends on the interpreter, and the labor cost is high, and the explanation time and content are fixed, which cannot meet the individual needs of visitors; the second is the button type guide machine, visitors need to rent equipment and listen to the explanation by manually inputting the product number or pressing the button, which is complicated to operate and affects the immersion of visitors, and the equipment also has problems such as maintenance, disinfection and loss; the third is two-dimensional code scanning, visitors need to scan the two-dimensional code with the mobile phone to jump to the explanation page, which depends on the network, and is not friendly to the audience who are not good at using smart devices (such as the elderly and children). Although the existing automatic induction technology (such as infrared, radar and ultrasonic wave) has been applied to other fields (such as automatic door and induction lamp), it is still in its infancy in the application of exhibition guide, and it is difficult to form a mature and intelligent guide solution, which cannot fully meet the needs of exhibition places for efficient, convenient and personalized guide service.

[0003] The existing exhibition guide related technology has many deficiencies. On the one hand, the traditional voice guide mode has obvious defects. The artificial explanation has high labor cost and lacks flexibility, the button type guide machine is complicated to operate and difficult to manage, and the two-dimensional code scanning depends on the network and has limited applicability, which is difficult to balance the visiting experience and guide efficiency. On the other hand, the automatic induction technology applied to exhibition guide has the following defects: first, the degree of intelligence is low, which cannot distinguish different states such as approaching, staying and leaving of visitors, and is easy to trigger or terminate the play; second, the content is not targeted, usually a sensor corresponds to a fixed audio, which cannot provide differentiated explanation for different interest points under the same product; third, the interaction is poor, which can only realize one-way audio output, cannot record visiting data, and cannot judge the interest degree of visitors according to the staying time; fourth, the anti-interference ability is weak, which is easy to produce false action due to personnel flow, light change and other external factors, resulting in unstable guide service. Therefore, in view of the above status, it is urgent to develop an infrared induction automatic voice broadcast exhibition device and method to overcome the deficiencies in current practical application. SUMMARY

[0004] The present application relates to the technical field of exhibition display, in particular to an infrared induction automatic voice broadcast exhibition device and method.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical scheme: The infrared induction automatic voice broadcasting exhibition device comprises a master control module, an infrared induction module, a voice broadcasting module, a storage module and a power management module. The power management module provides stable power supply for the master control module, the infrared induction module, the voice broadcasting module and the storage module. The infrared induction module is used for detecting visitors and inputting an induction signal to the master control module. The storage module interacts with the master control module to store audio files, configuration parameters and operation logs. The master control module is used for processing the induction signal input by the infrared induction module and controlling the voice broadcasting module to play the audio file stored in the storage module according to the induction signal.

[0006] As a further scheme of the present application, the infrared induction module is a modulated infrared induction module, comprising an infrared emitter tube and an infrared receiving head. The infrared emitter tube is used for emitting a modulated infrared signal of a preset wavelength, and the infrared receiving head is used for receiving the modulated infrared signal reflected by the visitors and converting it into an electric signal to be transmitted to the master control module.

[0007] As a further scheme of the present application, the peak wavelength of the infrared emitter tube is 940 nm. The receiving center frequency of the infrared receiving head is 37.9-39.4 kHz. The effective detection distance of the infrared induction module is 0.5-1 meter, and the effective detection angle is a 60° conical area in front.

[0008] As a further scheme of the present application, the master control module adopts a microcontroller with a Cortex-M3 core, the main frequency of the microcontroller is not less than 72 MHz, and the microcontroller is integrated with SPI and USART peripherals to schedule the cooperative work of various modules.

[0009] As a further scheme of the present application, the voice broadcasting module comprises an audio decoding chip, a power amplifier and a loudspeaker. The audio decoding chip is connected with the master control module, used for decoding the audio file in the storage module and outputting an audio signal. The power amplifier is used for amplifying the audio signal and driving the loudspeaker to play audio.

[0010] As a further scheme of the present application, the storage module adopts a Micro SD card, the Micro SD card supports the SDHC standard, adopts a FAT32 file system, and has a capacity not less than 16 GB.

[0011] As a further scheme of the present application: the power management module comprises a power interface and a voltage stabilizing chip; The power interface is adapted to 12V DC input, and the voltage stabilizing chip is an LDO voltage stabilizing chip, which is used to convert input voltage into 3.3V stable voltage to supply power to the master control module, the infrared sensing module, the storage module and the audio decoding chip.

[0012] As a further scheme of the present application: the wireless communication module is further included, and the wireless communication module is connected with the master control module; The wireless communication module is used to upload running data of the device to a cloud server, and the running data comprises a device unique identifier, an audio trigger timestamp and an audio playing duration.

[0013] An infrared sensing automatic audio playing exhibition method is applied to the infrared sensing automatic audio playing exhibition device, and comprises the following steps: S1: standby detection, after the device is powered on, the device enters a low-power standby state, and the infrared sensing module continuously detects whether there is a visitor in the sensing area; S2: signal judgment, when the infrared sensing module detects a sensing signal, the master control module judges the sensing signal for a preset delay time to filter out interference signals; S3: trigger playing, if the sensing signal is continuously valid within the preset delay time, the master control module controls the voice playing module to play a corresponding audio file in the storage module; S4: state monitoring and interruption processing, during the audio playing process, the master control module continuously monitors the visitor state through the infrared sensing module, and if it is detected that the visitor leaves, the voice playing module is controlled to stop playing; S5: reset and cycle, after the audio playing is stopped, the device is reset to the standby state, and steps S1-S4 are repeatedly executed.

[0014] As a further scheme of the present application: in step S2, the preset delay time is 100-500 ms; In step S4, if it is detected that the visitor leaves, the master control module controls the voice playing module to immediately stop playing or stop playing after a delay of 3 seconds.

[0015] Compared with the prior art, the present application has the following beneficial effects: 1. improve user experience: realize the intelligent explanation of "talking as soon as coming and stopping playing as soon as leaving", make the visiting process more smooth, greatly enhance the visiting immersion, and visitors can obtain explanation service without any operation; 2. High anti-interference: using modulation and demodulation technology and software delay judgment algorithm, it can effectively avoid the false triggering caused by ambient light, temperature change and instantaneous shielding, ensure the stable and reliable work of the device, and adapt to the complex environmental conditions of exhibition places; 3. Flexibility and scalability: the device structure is modularized, the sensing distance, audio content and triggering strategy can be flexibly adjusted according to different exhibition needs, and through adding optional modules such as wireless communication module, it can also be easily integrated into Internet of Things system to realize centralized management and big data analysis, and meet the personalized needs of different exhibition scenes; 4. Energy saving and environmental protection: when there is no audience, the device is in low-power standby state, only the infrared sensing and main control module circuit work, which can effectively save energy and reduce the energy consumption cost of exhibition operation; 5. Reduce the cost: reduce the dependence on artificial interpreters in exhibition hall, at the same time, avoid the rental and maintenance cost of a large number of guide equipment, significantly reduce the operation cost of guide service in exhibition place, and improve the cost performance of guide service. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 The module connection block diagram of the infrared sensing automatic sound playing exhibition device in the embodiment of the present application.

[0017] Figure 2 The shell structure schematic diagram of the infrared sensing automatic sound playing exhibition device in the embodiment of the present application.

[0018] Figure 3 The working method flow chart of the infrared sensing automatic sound playing exhibition device in the embodiment of the present application. Among them, (a) is the installation and physical layout schematic diagram of the infrared sensing automatic sound playing exhibition device; (b) is the hardware system architecture schematic diagram of the infrared sensing automatic sound playing exhibition device; (c) is the working flow schematic diagram of the infrared sensing automatic sound playing exhibition device; the installation and physical layout of (a) figure provides space deployment basis for the hardware system architecture of (b) figure, and the hardware module of (b) figure provides hardware support for the working flow execution of (c) figure, the three are sequentially connected and supported from physical deployment to hardware support to function implementation.

[0019] Figure 4 The hardware system architecture and working flow schematic diagram of the infrared sensing automatic sound playing device in the embodiment 1 of the present application.

[0020] Figure 5 The infrared receiving tube signal input judgment flow chart in the embodiment of the present application. DETAILED DESCRIPTION

[0021] With reference to the accompanying drawings, the technical solutions in the embodiments of the present application will be clearly and completely described below, obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work belong to the protection scope of the present application.

[0022] The specific implementation of the present application will be described in detail below in combination with specific embodiments.

[0023] Please refer to Figures 1-5 The infrared induction automatic voice broadcasting exhibition device and method provided in the embodiments of the present application realize non-sensing triggering, intelligent judgment, accurate orientation, and function integration and expansion. The device comprises a main control module (using a microcontroller or a microcomputer, processing sensor signals and executing control logic), an infrared induction module (at least one pair of infrared emitter tubes and receiver tubes, preferably a modulated infrared sensor, detecting the entry of visitors), a voice broadcasting module (containing an audio decoding chip, a power amplifier and a loudspeaker, storing and playing digital audio files), a storage module (storing audio, configuration parameters and operation logs), a power management module (stably supplying power, adapting to alternating current and direct current), and can also be provided with optional modules such as a wireless communication module, an LED indicator light, a multimedia output interface, and a multi-zone induction module. The working method comprises standby detection, signal judgment (delaying for 100-500 ms to filter out interference), triggering and playing, state monitoring and interruption processing (stopping immediately or delaying for 3 seconds when the visitor leaves), and resetting and cycling steps.

[0024] Embodiment 1: Infrared induction automatic voice broadcasting exhibition device The present embodiment provides an infrared induction automatic voice broadcasting exhibition device, which is suitable for the explanation of flat exhibits such as paintings, is installed on the wall below the painting, and can realize non-sensing triggering, intelligent judgment, and accurate orientation, effectively improving the visiting experience and reducing the probability of false triggering.

[0025] I. Hardware system architecture The infrared induction automatic voice broadcasting exhibition device of the present embodiment is a modular, low-power embedded system, and its hardware core comprises a main control module, an infrared induction module, a voice broadcasting module, a storage module, and a power management module. The selection and core parameters of each module are as follows, and each module works cooperatively to realize stable automatic voice broadcasting function, and at the same time, the anti-interference ability and operation reliability are improved through hardware selection and parameter design.

[0026] II. Installation and physical layout The infrared induction automatic broadcasting exhibition device of the embodiment is installed on the exhibition wall below the painting as a whole, and is arranged towards the visitors; the infrared induction module adjusts the induction area to a 60° conical area in front by optical structure, the effective detection distance is 0.5-1 meter, and an induction curtain is formed, the conical induction area covers the front of the painting, so that the system can be triggered only when the visitor approaches the painting and enters the induction area, the accidental triggering caused by passing people or people far away is avoided, and the accuracy of the explanation triggering is ensured.

[0027] III. Intelligent workflow The device of the embodiment realizes the intelligent explanation of "explanation as visitors come and stop when visitors leave" through the following intelligent workflow, and the interference is filtered through delay judgment and the like, so that the running stability is improved, and the specific process is as follows: Standby inspection stage: after the system is connected to the 12VDC power supply, the low-power standby state is entered, only the infrared induction module and the main control module part circuit work at this time, the energy is effectively saved, the infrared emitter continuously emits the 38kHz modulated signal under the control of the main control module, and the main control module cyclically detects the output state of the infrared receiver, and the entering of the visitors into the induction area is monitored in real time.

[0028] Intelligent triggering stage: when the visitor enters the 60° conical induction area, the human body will reflect the 38kHz modulated signal emitted by the infrared emitter, the infrared receiver (HS0038B) receives the reflected signal, converts it into a low-level electrical signal and transmits it to the main control module; after the main control module receives the low-level signal, a 200ms delay judgment (that is, the T1 threshold in the software filtering parameter) is started, only when the low-level signal is continuously stable and effective within 200ms, it is determined as an effective trigger, so as to filter out the interference caused by transient shielding such as flying insects, floating paper and short-time waving, and ensure the accuracy of the trigger judgment.

[0029] High-definition playing stage: if it is determined that the trigger is effective, the main control module reads the "painting explanation.MP3" audio file corresponding to the current painting from the TF card of the storage module through the SPI bus, and transmits the audio file data to the VS1053B audio decoding chip; after the VS1053B decodes the audio data, the audio signal is output to the PAM8403 power amplifier chip, and the audio signal amplified by the power amplifier chip drives the 3W loudspeaker to play the explanation content, so as to provide clear explanation service for the visitors.

[0030] Humanized interruption and reset stage: during the audio playing process, the main control module continuously monitors whether the visitor stays in the induction area through the infrared induction module: If the visitor stays in the sensing area, the infrared receiver continuously outputs a low-level signal, the audio is normally played until the end, and after the end, the device automatically resets and returns to the standby inspection stage, waiting for the next trigger. If the visitor leaves the sensing area, the infrared receiver output signal returns to high level, the main control module starts a 2-second delay judgment (T2 threshold in the software filter parameter), to prevent the guide from stopping due to the visitor's slight shaking, temporary retreat, etc. If the infrared receiver still does not return to low level signal after 2 seconds (i.e. the visitor does not return), the main control module controls the voice broadcast module to stop playing immediately, and controls the entire system to reset and return to the standby inspection stage. If the infrared receiver returns to low level signal within 2 seconds (i.e. the visitor returns), the audio continues to play.

[0031] IV. Detailed description of hardware circuit (I) System core circuit diagram The core circuit of the device in this embodiment is centered on the main control module (STM32F103C8T6), and the connection relationship of each functional module with the main control module is as follows: The AMS1117-3.3 chip of the power management module outputs 3.3V voltage, which powers the main control module, the receiver (HS0038B) of the infrared sensing module, the VS1053B chip of the voice broadcast module, and the TF card of the storage module. If the power amplifier chip PAM8403 needs 5V power supply, it can be powered by the MP1584EN DC step-down module after reducing the input voltage of 12V to 5V, or directly connecting PAM8403 to 12V input (through a fuse); The emitter tube (IR333-A) of the infrared sensing module is connected to the GPIO port (such as PA1) of the main control module in series with a 100Ω current limiting resistor, and the output end of the receiver (HS0038B) is connected to another GPIO port (such as PA0) of the main control module; The VS1053B chip of the voice broadcast module is connected to the main control module through the SPI1 bus, and the audio output end (GBUFF, LOUT / ROUT) of the VS1053B is connected to the input end of the PAM8403 power amplifier chip, and the output end of the power amplifier chip is connected to the 8Ω 3W speaker; The TF card of the storage module is connected to the main control module through the SPI2 bus; (II) Specific circuit and parameter design of each module 1. Power management module circuit Input circuit: use standard DC-005 socket (5.5mm x 2.1mm) as power interface, interface in series with a 1N4007 diode to prevent reverse connection, while connecting a 500mA self-resetting fuse (PPTC) to achieve overcurrent protection; in the input circuit parallel 100uF 25V electrolytic capacitor and 0.1uF 50V ceramic capacitor, used to filter out power ripple and noise, to ensure stable input voltage.

[0032] Voltage conversion circuit: 3.3V LDO linear voltage regulator circuit: using AMS1117-3.3 chip, its input end connects 12VDC input (after input circuit processing), output end outputs 3.3V stable voltage, power supply for STM32F103C8T6, VS1053B, TF card and other core chips; in the input and output end of AMS1117-3.3 parallel 10uF and 22uF ceramic capacitor, further filter out voltage ripple after voltage regulation.

[0033] 5V DCDC step-down circuit (optional): if the power amplifier chip PAM8403 needs 5V power supply, add MP1584EN DC step-down module to reduce 12V input voltage to 5V, the conversion efficiency of this module can reach more than 90%, reduce circuit heating, and ensure the stable work of power amplifier chip.

[0034] Power amplifier power supply circuit: the power supply end (VCC) of power amplifier chip PAM8403 can be directly connected to 12V input circuit (need to pass through self-resetting fuse), because its working voltage range is wide and can withstand high voltage, it can directly use 12V input voltage to ensure output power.

[0035] 2, infrared induction module circuit; Transmitting part circuit: infrared transmitting tube IR333-A in series with a 100Ω 1 / 8W current limiting resistor, connected to the GPIO port (such as PA1) of the main control module STM32F103C8T6; this GPIO port is configured as PWM (pulse width modulation) output mode by the timer (TIM) of STM32, generating a 38kHz±0.5kHz carrier signal, the duty cycle is set to about 50%, to drive the transmitting tube to emit modulated infrared signal, rather than continuous emission, this design is the key to resist environmental light interference, can avoid the influence of non-modulated infrared noise.

[0036] Receiving part circuit: adopt integrated infrared receiving head HS0038B, VCC pin connects 3.3V power supply, GND pin connects ground, OUTPUT pin is directly connected to another GPIO port (such as PA0) of STM32F103C8T6, and a 10kΩ resistor is pulled up between OUTPUT pin and 3.3V power supply; when HS0038B receives 38kHz modulated infrared signal, low level is output; when not received, high level is output, realizing detection of visitors in the sensing area.

[0037] Sensing performance guarantee: through the above circuit design, combined with the half-power angle (±20°) of the transmitting tube, the effective detection distance of the infrared sensing module is controlled at 0.3-1.5 meters (which can be flexibly adjusted by adjusting the PWM duty cycle or replacing the current limiting resistor), the detection angle (horizontal and vertical) is 20°-30°, the response time is <100ms, the working environment illumination range is 0-100000Lux, the working temperature range is -20℃-85℃, which can cover the environmental requirements of most indoor exhibition halls, and can effectively avoid the interference of environmental light, static heat source, etc.

[0038] 3. Main control and voice broadcast module circuit; Main control minimum system circuit: STM32F103C8T6 needs to connect the following necessary peripheral circuits to ensure normal work: Crystal circuit: connect 8MHz high-speed crystal, 1MΩ feedback resistor and 20pF load capacitor are connected in parallel at both ends of the crystal, to provide stable clock signal for the chip; Reset circuit: one end of 10kΩ pull-up resistor is connected to 3.3V power supply, the other end is connected to the reset pin of STM32, the reset pin is also connected to ground through 0.1μF capacitor, to form a power-on reset circuit; Boot mode circuit: BOOT0 pin is pulled down to ground through 10kΩ resistor, so that the chip starts from the main Flash; Debug interface circuit: SWDIO and SWCLK pins are introduced, which are used for program download and debugging.

[0039] SPI connection circuit of main control and VS1053B: STM32F103C8T6 is connected with VS1053B through SPI1 bus, the specific pin correspondence is shown in the following table, through which the control of VS1053B by the main control and audio data transmission are realized:

[0040] Audio output circuit: the left and right channel output pins (GBUFF, LOUT / ROUT) of VS1053B are connected to the input terminals of PAM8403 power amplifier chip through 10μF coupling capacitors to isolate the DC component; the output terminals of PAM8403 are directly connected to 8Ω 3W loudspeakers to realize the amplification and playing of audio signals, and to ensure that the explanation sound is clear and loud.

[0041] 4, storage module circuit; The storage module is connected to the MicroSD card seat in SPI mode, and the SPI2 pins (PB12 / CS, PB13 / SCK, PB14 / MISO, PB15 / MOSI) of STM32F103C8T6 are connected to the corresponding pins of the SD card seat. Since the SD card is a 3.3V device, it can be directly connected to STM32F103C8T6 without the need for level conversion; at the same time, a 33Ω resistor is connected in series on the SDIO_D0, SDIO_CMD and other signal lines of the SD card seat, and a 10kΩ resistor is pulled up to 3.3V to improve signal integrity and ensure stable read and write operations of the host module on the SD card.

[0042] (Three) core chip communication process; 1. SPI communication process between STM32 and VS1053B; a. Initialization phase: 1) GPIO and SPI initialization: configure STM32's SPI1 to work in host mode, set SPI_Baud RatePrescaler_256 clock divider to get a clock of about 280kHz, which meets the timing requirements of VS1053B; at the same time, configure XCS, XDCS, DREQ, XRESET pins to the corresponding output or input mode.

[0043] 2) VS1053B reset: pull down the XRESET pin for at least several microseconds, then pull up the pin, complete the hardware reset of VS1053B.

[0044] 3) VS1053B register configuration: configure the registers of VS1053B through the SCI (Serial Command Interface) bus, specifically, pull down the XCS pin (select the command channel), send the "write register" command through the MOSI line of SPI, for example, set the clock register SM_CLOCKF to 0x8800 to increase the internal clock frequency, set the mode register SM_MODE to enable MP3 decoding function, and set the volume register SM_VOL to initialize the playback volume.

[0045] b. Audio playback loop phase: 1) DREQ pin monitoring: STM32 continuously detects the state of the DREQ pin of VS1053B to determine whether its audio data buffer is idle.

[0046] 2) Data transmission judgment: When the DREQ pin outputs a high level, it indicates that the audio data buffer of VS1053B is idle and can receive at least 32 bytes of new data.

[0047] 3) Audio data transmission: STM32 pulls down the XDCS pin (selects the data channel), and sends the 32-byte audio data block read from the TF card to VS1053B through the MOSI line of SPI.

[0048] 4) Data transmission end: After the transmission of a single block of data is completed, pull up the XDCS pin to end this data transmission.

[0049] 5) Loop transmission: Repeat steps 1-4 until all data of the current audio file is sent.

[0050] 6) Play end processing: After all audio data is sent, send the "play end" command to VS1053B through the SCI bus, and VS1053B will automatically stop playing after receiving the command.

[0051] c. Infrared sensing and audio playback linkage: The state detection of the infrared sensor is realized through the main loop or external interrupt of STM32; when the algorithm determines that it is "valid trigger", STM32 reads the corresponding MP3 file from the TF card through SPI2 interface, and transmits the data to VS1053B according to the above audio playback loop process; when the algorithm determines that the audience has left, STM32 immediately stops sending audio data, and sends a "soft reset" command (SM_CANCEL) to VS1053B through the SCI bus to make it stop playing and clear the buffer.

[0052] 2, Circuit and software implementation of anti-interference algorithm; Hardware layer anti-interference implementation: The hardware anti-interference is realized through the 38kHz modulation and demodulation design of the infrared sensing module, that is, the infrared emitting tube emits a 38kHz carrier pulse, and the infrared receiving head HS0038B integrates a demodulation circuit inside, which is only sensitive to 38kHz frequency infrared light. Visible light, incandescent lamp, fluorescent lamp and other light sources in the environment do not contain 38kHz modulation signal, which will be greatly attenuated by the filter and frequency selection circuit inside the receiving head, and cannot produce effective output signal, thus fundamentally eliminating more than 90% of non-modulated light source interference. The physical signal is converted into digital signal (low level valid / high level invalid), which provides clean data basis for software processing.

[0053] Software Layer Anti-Interference Implementation: The software anti-interference is realized by using a decision algorithm based on Finite-State Machine (FSM). The algorithm defines four system states, and intelligent judgment is realized through state transition. The specific implementation is as follows: State Definition: State 0 (Idle State): The system waits for valid triggers and is in a low-power monitoring state; State 1 (Pre-trigger State): A valid infrared signal is detected, and a delay judgment is entered; State 2 (Playing State): A valid trigger is confirmed, and audio is being played; State 3 (Leaving Judgment State): The infrared signal is lost during playback, and a leaving delay judgment is entered.

[0054] State Transition Logic (Corresponding Pseudo Code as Follows): / / Pseudo Code Example (C Language Style) #define T1_THRESHOLD 200 / / Valid trigger delay threshold (ms), filter transient interference #define T2_THRESHOLD 2000 / / Leaving judgment delay threshold (ms), prevent false stop enum State{STATE_IDLE,STATE_PRE_TRIGGER,STATE_PLAYING,STATE_LEAVING_CHECK}; State currentState = STATE_IDLE; uint32_t timer = 0; void loop() { int irSignal = readIRSensor(); / / Read the infrared sensor state (0: blocked / valid, 1: no block / inactive) switch (currentState) { case STATE_IDLE: if (irSignal == 0) { / / Detect obstruction, possible visitor entry currentState = STATE_PRE_TRIGGER; timer = millis(); / / Start T1 timer } break; case STATE_PRE_TRIGGER: if (irSignal == 1) { / / Signal restored in advance, determined as transient interference (such as flying insects) currentState = STATE_IDLE; / / System reset to idle state } else if (millis() - timer >= T1_THRESHOLD) { / / Signal duration T1 above, determine valid trigger startPlayback(); / / Start audio playback currentState = STATE_PLAYING; } break; case STATE_PLAYING: if (irSignal == 1) { / / Signal disappears in playing, possible audience leaving currentState = STATE_LEAVING_CHECK; timer = millis(); / / Start T2 timer } break; case STATE_LEAVING_CHECK: if (irSignal == 0) { / / Signal restores within T2 time, determine audience sway currentState = STATE_PLAYING; / / Continue playing audio } else if (millis() - timer >= T2_THRESHOLD) { / / Signal persists disappear T2 above, determine audience leaving stopPlayback(); / / Stop audio playback currentState = STATE_IDLE; / / System reset to idle state } break; } } The algorithm combines hardware modulation and demodulation with software timing filtering to form a double-filter defense system, which has strong anti-interference ability; T1 (200 ms) and T2 (2000 ms) are independent delay parameters, T1 pursues response speed to filter the instantaneous interference when entering, and T2 pursues stability to prevent false stop when leaving; The state machine model is logically rigorous, avoiding the logical confusion of traditional simple judgment; The parameters can be modified according to the scene (such as extending T1 and shortening T2 in areas with large flow of people), which has strong adaptability, making the device upgrade from toy-level application to commercial-level application.

[0055] Embodiment 2: Vertical exhibition cabinet broadcasting device integrated with data uploading function; This embodiment is based on embodiment 1, and adds a wireless communication module (Wi-Fi module) to realize the uploading function of the visiting data, provides data support for exhibition operation, and is suitable for vertical exhibition cabinet type exhibits (such as cultural relic exhibition cabinets). The hardware system architecture, installation layout, working process and anti-interference algorithm of this embodiment are the same as those of embodiment 1, only the hardware, software and data uploading process related to the Wi-Fi module are newly added, which are as follows: I. New hardware module (Wi-Fi module); The newly added Wi-Fi module of this embodiment adopts ESP8266-12F (built-in TCP / IP protocol stack, supporting AT instruction set), which cooperates with the main control module to realize data uploading. The specific hardware parameters and connections are as follows:

[0056] 1. Hardware connection of Wi-Fi module and main control module; ESP8266-12F is connected with STM32F103C8T6 through UART (Universal Asynchronous Receiver / Transmitter) protocol. The specific pin correspondence is shown in the following table. It should be noted that the RX pin of ESP8266 can withstand a maximum voltage of 3.3V, and it is strictly forbidden to be connected with 5V TTL devices as shown in the following table:

[0057] In addition, ESP8266-12F needs to be configured with the following auxiliary circuits: CH_PD pin is pulled up to 3.3V through 10kΩ resistor, so that the module is always enabled; GPIO0 pin is pulled up to 3.3V through 10kΩ resistor, to ensure that the module starts from the internal Flash; RST pin is reserved to ground through a button, which is used for manual reset.

[0058] II. Software configuration process of Wi-Fi module; The ESP8266-12F is initialized and communication is controlled through the AT command set. The STM32F103C8T6 sends AT commands to it through USART1 and waits for an "OK" response to confirm that the configuration is successful. The initialization process is only executed once after the system is powered on. The specific steps are as follows: Module restart: The STM32 sends the command "AT+RST", and the ESP8266 returns "OK" after restarting, completing the module reset.

[0059] Working mode setting: The STM32 sends the command "AT+CWMODE=1" to set the ESP8266 to Station (client) mode, making it connectable to the router in the exhibition hall. The ESP8266 returns "OK" to indicate that the setting is successful.

[0060] Router connection: The STM32 sends the command AT+CWJAP=“Your_SSID”,“Your_Password” (where "Your_SSID" is the wireless network name of the exhibition hall router, and "Your_Password" is the router password). The ESP8266 returns "OK" after successfully connecting to the router, or an error code if the connection fails. The STM32 can start a retry mechanism.

[0061] Connection mode setting: The STM32 sends the command "AT+CIPMUX=0" to set the ESP8266 to single connection mode, i.e., only one TCP connection is established at a time. The ESP8266 returns "OK".

[0062] Transparency mode enabled: The STM32 sends the command "AT+CIPMODE=1" to enable the transparency mode of the ESP8266. Subsequent data sent through UART will be directly transmitted to the established server. The ESP8266 returns "OK" to indicate that the transparency mode is enabled successfully.

[0063] III. Visit data upload process The device of this embodiment automatically triggers the data upload process at the end of each audio playback period (including normal playback and playback stop due to audience leaving), and sends visit data to the cloud server. The curator can view the data through the background management system. The specific process is as follows: TCP connection establishment: The STM32 sends the command "AT+CIPSTART=“TCP”,“api.ypur-cloud.com”,80" (where "api.ypur-cloud.com" is the domain name of the cloud server, and "80" is the default port of HTTP protocol). The ESP8266 establishes a TCP connection with the cloud server, and returns "OK" after the connection is successful.

[0064] Transmit mode entry: STM32 sends the command "AT+CIPSEND", and ESP8266 returns ">" to indicate that it has entered the transparent transmission mode and is ready to receive data.

[0065] HTTP POST request assembly and sending: STM32 assembles a POST request containing visit data according to the HTTP protocol specification. The request body (Body) is in JSON format and contains three core data fields: "device_id": a unique identifier for the device (such as "Cabinet01-001", used to distinguish different display cabinet devices); "trigger_time": audio trigger timestamp (generated by STM32's RTC real-time clock module, format like "20230920103025", representing September 20, 2023, 10:30:25); "duration": the duration of this audio playback (unit: seconds, generated by STM32 timing, such as "12" indicating a 12-second playback). STM32 sends the assembled HTTP POST request to ESP8266 through UART. The example request is as follows: POST / api / data / upload HTTP / 1.1\r\n Host: api.your-cloud.com\r\n Content-Type: application / json\r\n Content-Length: 68\r\n \r\n / / empty line, separates Header and Body {"device_id":"Cabinet01-001","trigger_time":"20230920103025","duration":12}\r\n Transmit exit and connection closure: After data transmission is complete, STM32 sends +++ (without line feed) to exit the transparent transmission mode, and ESP8266 returns "OK"; then STM32 sends the command "AT+CIPCLOSE" to close the TCP connection with the cloud server, and ESP8266 returns "OK", ending the data upload process.

[0066] Four, system integration design; Non-blocking design: network communication (connection, data transmission) takes a long time, STM32 uses non-blocking code writing, divides the network operation into multiple states (such as TCP connection, data transmission and connection closing), and executes step by step in the main loop, avoids using while loop to respond, prevents the core functions such as infrared detection and audio playback from being dead, and ensures the overall stability of the system.

[0067] Error handling mechanism: timeout retry logic is set in the code, if a certain AT command does not receive an "OK" response within a predetermined time (such as 5 seconds), STM32 starts retry (retry times can be configured, such as 3 times), if the retry fails, the error log is recorded to the TF card, and the data is re-uploaded after the network is restored, ensuring the reliability of data upload.

[0068] Low power consumption consideration: if the device is powered by a battery, STM32 makes ESP8266 enter deep sleep mode through AT command "AT+GSLP" when there is no data upload task, and only wakes up ESP8266 through RST pin when data needs to be transmitted, which greatly reduces the power consumption of Wi-Fi module and prolongs the battery life.

[0069] Therefore, by adding a Wi-Fi module and a data upload process, the curator can view the popularity of each exhibit (by counting the number of triggers) and the average audience stay time (by counting the play time) through the background management system in real time, providing data support for exhibition effect evaluation, exhibit placement optimization and content adjustment, and improving the fine level of exhibition operation; At the same time, this design only adds one module based on embodiment 1, has strong compatibility, can flexibly choose whether to integrate according to the exhibition demand, and has good expansibility.

[0070] It should be noted that in the present application, it should be understood that although the present application is described in the form of embodiments, each embodiment does not contain only one independent technical solution, and the description manner of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be combined appropriately to form other embodiments that those skilled in the art can understand.

Claims

1. An infrared-sensing automatic audio-visual exhibition device, characterized in that, The module includes a main control module, an infrared induction module, a voice broadcast module, a storage module and a power management module. The power management module provides stable power supply for the main control module, the infrared induction module, the voice broadcast module and the storage module. The infrared induction module is used for detecting visitors and inputting an induction signal to the main control module. The storage module interacts with the main control module to store audio files, configuration parameters and running logs. The main control module is used for processing the induction signal input by the infrared induction module and controlling the voice broadcast module to play the audio file stored in the storage module according to the induction signal. The infrared induction module and the main control module cooperatively realize multi-modal anti-interference: the infrared induction module realizes hardware filtering through a modulated signal, and the main control module realizes software filtering through delay judgment, so that the anti-interference capability is improved; and the power management module only supplies power to the core circuit of the infrared induction module and the main control module when there is no visitor, so that low-power standby is realized.

2. The infrared-sensing, automatic audio presentation display device of claim 1, wherein, The infrared induction module is a modulated infrared induction module, which includes an infrared emitter tube and an infrared receiver head. The infrared emitter tube is used for emitting a modulated infrared signal of a preset wavelength, and the infrared receiver head is used for receiving the modulated infrared signal reflected by the visitor and converting the modulated infrared signal into an electric signal to be transmitted to the main control module.

3. The infrared sensing automatic audio exhibition apparatus according to claim 2, wherein The peak wavelength of the infrared emitter tube is 940 nm. The receiving center frequency of the infrared receiver head is 37.9-39.4 kHz. The effective detection distance of the infrared induction module is 0.5-1 m, and the effective detection angle is a 60° conical area in front.

4. The infrared sensing automatic audio exhibition apparatus according to claim 1, wherein The main control module adopts a microcontroller with a Cortex-M3 core, the main frequency of the microcontroller is not less than 72 MHz, and the microcontroller is integrated with SPI and USART peripherals and is used for scheduling the cooperative work of various modules.

5. The infrared sensing automatic audio exhibition apparatus according to claim 1, wherein The voice broadcast module includes an audio decoding chip, a power amplifier and a loudspeaker. The audio decoding chip is connected with the main control module and is used for decoding the audio file in the storage module and outputting an audio signal. The power amplifier is used for amplifying the audio signal and driving the loudspeaker to play audio.

6. The infrared sensing automatic audio exhibition apparatus according to claim 1, wherein The storage module adopts a Micro SD card, the Micro SD card supports the SDHC standard, adopts a FAT32 file system and has a capacity of not less than 16 GB.

7. The infrared sensing automatic audio exhibition apparatus according to claim 1, wherein The power management module includes a power interface and a voltage stabilizing chip. The power interface is adapted to 12V DC input, the voltage stabilizing chip is an LDO voltage stabilizing chip and is used for converting the input voltage into a 3.3V stable voltage to supply power to the main control module, the infrared induction module, the storage module and the audio decoding chip.

8. The infrared sensing automatic audio exhibition apparatus according to claim 1, wherein The wireless communication module is connected with the main control module. The wireless communication module is used for uploading running data of the device to a cloud server, and the running data includes a device unique identifier, an audio trigger timestamp and an audio playing duration.

9. An infrared-sensing automatic voice broadcasting exhibition method applied to the infrared-sensing automatic voice broadcasting exhibition device of claim 1, characterized in that, The following steps are included: S1: standby detection, after the device is powered on, the device enters a low-power standby state, and the infrared induction module continuously detects whether there is a visitor in the induction area. S2: signal judgment, when the infrared sensing module detects a sensing signal, the main control module judges the sensing signal for a preset delay time to filter out interference signals; S3: trigger playing, if the sensing signal is continuously valid within the preset delay time, the main control module controls the voice broadcast module to play the corresponding audio file in the storage module; S4: state monitoring and interruption processing, in the audio playing process, the main control module continuously monitors the visitor state through the infrared sensing module, and if it is detected that the visitor leaves, the voice broadcast module is controlled to stop playing; S5: reset and cycle, after the audio playing stops, the device resets to the standby state, and steps S1-S4 are repeatedly executed; The main control module realizes anti-interference through trigger delay and leave delay, the trigger delay filters out transient interference, and the leave delay avoids false stop; the method realizes intelligent judgment through state switching logic, covering the whole scene of visitor entering-staying-leaving.

10. The method of claim 9, wherein the infrared sensing automatic voice broadcasting exhibition method is characterized by, In step S2, the preset delay time is 100-500 ms; In step S4, if it is detected that the visitor leaves, the main control module controls the voice broadcast module to immediately stop playing, or to stop playing after a delay of 3 seconds.

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