Alarm device and method integrating spatial audio and waistband type tactile feedback

Abstract

The invention relates to an alarm device and method integrating spatial audio and waistband type tactile feedback, and belongs to the field of man-machine interaction. Comprising a microprocessor, a wireless communication module, a memory, an audio driving circuit, a tactile driving circuit, a tactile feedback waistband, audio equipment and a power supply system, alarm space audio containing direction information is generated through the head-related transfer function technology, tactile feedback is provided through a linear motor array, and auditory and tactile synchronous alarm is achieved. The method has the advantages that more accurate and effective dangerous information transmission is provided by combining the spatial audio technology and the tactile feedback technology, and the method aims at solving the problems that in the flying or vehicle driving process, the alarm feedback mode is single, and the real-time performance of dangerous information obtaining is insufficient. The system has the advantages of multi-sensory synchronous perception and timely directional prompt, can significantly improve the perception ability and response speed of a user to danger in a complex environment, and improves the reliability and practicability of an alarm device.

Description

Technical Field

[0001] The present invention belongs to the field of human-computer interaction, and in particular relates to an alarm device and method integrating spatial audio and belt-type tactile feedback. Background Art

[0002] With the rapid development of science and technology, wearable devices are increasingly used in virtual reality, smart driving and other fields. In these fields, accurate information transmission and efficient interaction become particularly important. Especially for professional groups such as pilots and drivers, how to effectively obtain and process a large amount of information in a complex environment to reduce workload and improve safety and efficiency is an urgent problem to be solved.

[0003] Currently, wearable devices mainly rely on vision and hearing for information transmission. However, in some cases, such as flying or driving, visual information may be too dense or difficult to process, and auditory information alone may not be enough to provide accurate spatial positioning. Therefore, exploring new ways of information transmission, especially those combining hearing and touch, is of great significance to improving the human-computer interaction experience and efficiency.

[0004] Spatial audio technology can provide a more realistic and three-dimensional auditory experience by simulating the propagation of sound in space. Haptic feedback technology can provide intuitive tactile stimulation through vibration and other means to help users better understand and respond to information. However, existing technologies are insufficient in terms of the accuracy of spatial audio positioning, the diversity of tactile feedback, and the effectiveness of the combination of the two technologies. Specifically, existing technologies have problems when processing complex environmental information, such as visual information overload and insufficient auditory information to provide accurate spatial positioning, which limits their scope of application and efficiency.

[0005] There are already some warning devices used in driving behavior.

[0006] Chinese patent "A belt-type driving safety tactile system" CN104417430A discloses a tactile feedback belt that can be used when driving a car. The device is connected to sensor modules distributed around the car and analyzes and processes sensor data to provide vibration tactile reminders for safe driving. Its tactile module is composed of a 1X7 motor array, and the danger source provided is horizontal. The warning method is relatively simple and does not combine multiple channels for more efficient warnings.

[0007] Chinese patent "A wearable device with temperature and vibration perception" CN103735395B discloses a wearable device with a combination of temperature and touch prompts that can be used for navigation and gaming. The device consists of a temperature wristband, a vibration leggings, a vibration belt and a backpack. The temperature wristband uses hot and cold stimulation to indicate the threat level, and the vibration belt indicates the target's position and status. It can effectively provide synchronous prompts, but it has many components and is slightly cumbersome to wear. Summary of the invention

[0008] The present invention provides a warning device and method integrating spatial audio and belt-type tactile feedback, so as to solve the problem that the warning feedback mode is single and the real-time acquisition of danger information is insufficient during flight or vehicle driving.

[0009] The technical solution adopted by the present invention is to include a microprocessor, a wireless communication module, a memory, an audio driving circuit, a tactile driving circuit, a tactile feedback belt, an audio device and a power supply system;

[0010] The microprocessor is responsible for receiving danger information sent by external sensors, analyzing data such as danger location and urgency, and generating and outputting corresponding spatial audio signals and tactile feedback signals;

[0011] The wireless communication module receives danger alarm information from the environment in real time via Bluetooth or other wireless protocols and transmits it to the microprocessor;

[0012] The memory is used to store audio samples, head-related transfer function HRTF data sets and tactile feedback parameters, and the microprocessor calls these data to generate spatial audio signals;

[0013] The audio driving circuit includes a FIFO buffer, a D / A converter and an audio amplifier, which are used to convert digital audio signals into analog signals and amplify them into audio signals suitable for output through headphones or speakers;

[0014] The tactile drive circuit comprises an I2C multiplexer and a tactile driver, which is used to receive tactile instructions from a microprocessor, generate a vibration signal to drive the tactile feedback belt to produce a vibration tactile alarm;

[0015] The tactile feedback belt includes a linear motor array that generates vibration signals through a microprocessor-controlled tactile drive circuit to provide directional tactile feedback to indicate the source of danger;

[0016] The audio device includes headphones or speakers, which are used to output spatial audio signals to help users perceive the source direction and danger type of the alarm through hearing;

[0017] The power supply system provides stable power to all components and supports power supply from rechargeable lithium batteries or AC power supply.

[0018] A warning method integrating spatial audio and belt-type tactile feedback comprises the following steps:

[0019] (1) The microprocessor controls the wireless communication module to receive danger alarm information from environmental sensors, analyze data of different danger levels and sources, determine their priorities, and create dedicated storage space in the memory for each alarm information for subsequent processing and retrieval;

[0020] (2) Based on the stored danger alarm information, the microprocessor calls the audio samples and the head-related transfer function (HRTF) data set to generate a spatial audio signal related to the direction of the danger source. Through the HRTF technology, the user can clearly perceive the danger direction through stereo headphones;

[0021] (3) The microprocessor further optimizes the generated spatial audio signal and dynamically adjusts the interaural time difference of the audio signal according to the distance and direction of the danger source to ensure that the user accurately perceives the danger location and urgency. The optimized binaural audio signal is stored in a FIFO buffer at a fixed sampling rate for subsequent scheduling and output;

[0022] (4) The microprocessor determines the tactile feedback mode according to the danger alarm information, including selecting the vibration motor, setting the vibration waveform, and calculating the frequency and intensity, and generates control instructions, which are transmitted to the tactile driver through the I2C multiplexer to complete the vibration parameter configuration;

[0023] (5) To achieve synchronous start of audio and tactile signals, the microprocessor simultaneously activates the external trigger pin of the tactile driver and starts the timer interrupt. The timer generates a clock signal to control the FIFO buffer to output the audio signal. After the preset time is reached, the trigger pin is set to a low level and the timer interrupt is turned off, ensuring that the audio and tactile signals end synchronously.

[0024] (6) The spatial audio signal output from the FIFO buffer is converted into an analog signal by a D / A converter, amplified by an audio amplifier, and finally transmitted to an audio output device to complete the output of the spatial audio alarm;

[0025] (7) While the audio signal is being output, the tactile feedback module activates the linear motor array on the belt according to the set vibration parameters, providing vibration feedback corresponding to the danger direction, thereby achieving synchronous auditory and tactile alarms;

[0026] (8) The microprocessor continuously monitors the output status of the audio and tactile feedback signals, dynamically adjusts the parameters of the two to ensure the accuracy and consistency of the alarm signal, and collects user feedback data for subsequent optimization and performance improvement of the system.

[0027] The danger alarm information in step (1) of the present invention includes the direction of the threat (θ, φ), where θ represents the angle in the horizontal direction, measured clockwise from the left ear, and φ represents the angle in the vertical direction, measured upward from the horizontal plane, as well as the distance d and the threat type E;

[0028] The microprocessor analyzes the information, determines its priority, and creates a data storage space Buf in the memory to store the information, waiting for use in subsequent audio and tactile signal synthesis.

[0029] The step (2) of the present invention specifically includes: calling the corresponding preset audio sample A from the memory s (t), unprocessed mono audio signal, representing a specific warning sound effect, and head-related transfer function (HRTF) dataset, used to generate spatial audio S stereo (t):

[0030] The audio sample As(t) is transformed by Fourier Convert to frequency domain representation As(ω):

[0031]

[0032] Combined with the left and right ear HRTF frequency domain data (H L (ω),H R (ω)), and perform convolution calculations respectively to obtain the left and right ear signals in the frequency domain:

[0033] S L (ω)=A s (ω)·H L (ω)

[0034] S R (ω)=A s (ω)·H R (ω)

[0035] The frequency domain signals S of the left and right ears L (ω) and S R (ω) is obtained by inverse Fourier transform Convert back to the time domain:

[0036]

[0037] The audio signals of the left and right ears are combined into a two-channel stereo signal:

[0038] S stereo (t) = [S L (t),S R (t)].

[0039] The steps of optimizing the generated spatial audio signal in step (3) of the present invention are as follows:

[0040] The interaural time difference (ITD) of binaural audio signals is dynamically adjusted based on the distance, direction and urgency of the danger source. The interaural time difference (ITD) is the time difference between the sound reaching the left and right ears due to the direction of the sound source relative to the head. The ITD can be calculated by the formula:

[0041]

[0042] Where d is the distance between the left and right ears, c is the speed of sound, θ is the horizontal angle of the sound source, and the value of cosθ is in [-1,1]. Due to ITD, the audio signal S received by the left and right ears is L (t) and S R (t) will have a time offset. To achieve synchronous output, the right ear signal S R (t) Delay compensation is required:

[0043] S stereo (t) = [S L (t),S R (t+ITD)]

[0044] The microprocessor processes the audio signal S L (t) and S R (t+ITD) is based on the sampling rate f s They are written into their respective FIFO buffers and wait for further scheduling and output.

[0045] The frequency f of the audio signal of the present invention audio =44.1kHz. According to Nyquist sampling theorem, in order to ensure better signal reproduction and leave margin, the sampling rate should be greater than twice the signal frequency. s =100kHZ.

[0046] In step (4) of the present invention, the microprocessor determines the activation mode of the tactile motor array according to the stored danger alarm information, specifically including selecting the motor number of the vibration, the waveform of the motor vibration, calculating the frequency and intensity of the vibration, generating an instruction for controlling the tactile driver, and transmitting the instruction to the tactile driver through the multiplexer to set the vibration parameters;

[0047] The microprocessor selects the motor Mi to be activated, sends a control channel I2C command to the multiplexer Mux, and the multiplexer controls the opening of the channel Ch.i corresponding to the selected linear motor Mi;

[0048] After selecting the channel, the microprocessor sends a tactile alarm instruction to the target tactile driver through the channel. The instruction sets the waveform register, frequency register, intensity register, play time register, and start register of the tactile driver. This method controls the vibration parameters of the tactile alarm signal: waveform, frequency f haptic , Amplitude A vi , time t, when the waveform is a sinusoidal signal, the tactile signal expression is:

[0049] V i (t) = A vi ·sin(2πf i t).

[0050] The method for realizing synchronous start of audio and tactile signals in step (5) of the present invention is that the microprocessor activates the external trigger pin of the configured tactile driver; the audio signals of the left and right ears are activated at f s =100 kHz sampling rate is stored in two FIFO buffers respectively. The microprocessor configures a timer, and the interrupt period of the timer is set to T clk =10μs. Each time the timer interrupt is triggered, the microprocessor enters the interrupt service routine ISR and switches the FIFO_clk pin level: the FIFO_clk pin switches from low level to high level and then switches back to low level to generate a complete clock pulse. When each clock pulse arrives, the two FIFO buffers output the left ear signal S respectively. L (t) and the right ear compensation signal S R (t+ITD) from a sampling point to the subsequent audio driving circuit to ensure the time consistency of the left and right ear audio signals;

[0051] Microprocessor synchronous alarm: When the alarm moment comes, the microprocessor sets these four pins to high level, and the corresponding numbered tactile driver immediately performs tactile alarm according to the set vibration parameters. When the tactile alarm is turned on, the timer interrupt loop is started to generate the FIFO_clk clock signal to control the FIFO buffer to output the alarm space audio;

[0052] The spatial audio signal is output by the parallel FIFO buffer controlled by the timer interrupt, and the tactile alarm signal is output by controlling the tactile driver to drive the motor. After the alarm starts for a period of time Ts, the external trigger pin level of the tactile driver is restored to a low level, and the timer loop is closed at the same time to achieve the synchronous termination of the audio signal and the tactile signal.

[0053] The present invention adopts spatial audio and tactile feedback technology and discloses an alarm device that integrates spatial audio and belt-type tactile feedback. The device receives external danger information through wireless communication and transmits the information to a microprocessor. The head-related transfer function technology is combined with audio samples to generate spatial audio. The tactile feedback module (linear motor array) located on the belt is driven to generate vibration tactile according to the location and severity of the danger. By configuring the microprocessor to synchronously output spatial audio and waist vibration tactile, timely and diverse alarm feedback is achieved, thereby providing a fusion alarm device and method for scenarios such as human-computer interaction, driving assistance, and personal safety devices.

[0054] The present invention has the following advantages:

[0055] (1) Multi-sensory synchronous perception: The present invention combines spatial audio and tactile feedback technology to improve the efficiency and accuracy of alarm information transmission through dual stimulation of hearing and touch. This multi-sensory synchronous effect can significantly enhance the user's perception ability, especially in complex and noisy environments. It can provide more accurate and effective spatial information transmission, thereby providing more effective information transmission and interaction methods in complex environments.

[0056] (2) Accurate directional warning: Through spatial audio technology, the present invention can promptly determine the location and priority of danger, and provide directional information in combination with tactile feedback. This accurate directional warning function is particularly important for situations that require rapid response and accurate judgment (such as driving, flying, etc.). BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 It is a physical composition diagram of the present invention;

[0058] Figure 2 It is a principle block diagram of the present invention;

[0059] Figure 3 This is the principle block diagram of the audio driver circuit;

[0060] Figure 4 This is the principle block diagram of the tactile drive circuit;

[0061] Figure 5 is a schematic diagram of the linear motor array distribution;

[0062] Figure 6 is the linear motor vibration frequency response diagram;

[0063] Figure 7 It is a diagram of the motor array encoding scheme;

[0064] Figure 8 It is a multiplex communication timing diagram;

[0065] Fig. 9It is a timing diagram of microprocessor synchronous alarm;

[0066] Fig.10 It is a schematic diagram of tactile and auditory synchronous alarm. DETAILED DESCRIPTION

[0067] It includes a microprocessor, a wireless communication module, a memory, an audio drive circuit, a tactile drive circuit, a tactile feedback belt, an audio device and a power supply system;

[0068] The microprocessor is responsible for receiving danger information sent by external sensors, analyzing data such as danger location and urgency, and generating and outputting corresponding spatial audio signals and tactile feedback signals;

[0069] The wireless communication module receives danger alarm information from the environment in real time via Bluetooth or other wireless protocols and transmits it to the microprocessor;

[0070] The memory is used to store audio samples, head-related transfer function HRTF data sets and tactile feedback parameters, and the microprocessor calls these data to generate spatial audio signals;

[0071] The audio driving circuit includes a FIFO buffer, a D / A converter and an audio amplifier, which are used to convert digital audio signals into analog signals and amplify them into audio signals suitable for output through headphones or speakers;

[0072] The tactile drive circuit comprises an I2C multiplexer and a tactile driver, which is used to receive tactile instructions from a microprocessor, generate a vibration signal to drive the tactile feedback belt to produce a vibration tactile alarm;

[0073] The tactile feedback belt includes a linear motor array that generates vibration signals through a microprocessor-controlled tactile drive circuit to provide directional tactile feedback to indicate the source of danger;

[0074] The audio device includes headphones or speakers, which are used to output spatial audio signals to help users perceive the source direction and danger type of the alarm through hearing;

[0075] The power supply system provides stable power to all components and supports power supply from rechargeable lithium batteries or AC power supply.

[0076] A warning method integrating spatial audio and belt-type tactile feedback comprises the following steps:

[0077] (1) The microprocessor controls the wireless communication module to receive danger alarm information from environmental sensors, analyze data of different danger levels and sources, determine their priorities, and create dedicated storage space in the memory for each alarm information for subsequent processing and retrieval;

[0078] (2) Based on the stored danger alarm information, the microprocessor calls the audio samples and the head-related transfer function (HRTF) data set to generate a spatial audio signal related to the direction of the danger source. Through the HRTF technology, the user can clearly perceive the danger direction through stereo headphones;

[0079] (3) The microprocessor further optimizes the generated spatial audio signal and dynamically adjusts the interaural time difference of the audio signal according to the distance and direction of the danger source to ensure that the user accurately perceives the danger location and urgency. The optimized binaural audio signal is stored in a FIFO buffer at a fixed sampling rate for subsequent scheduling and output;

[0080] (4) The microprocessor determines the tactile feedback mode according to the danger alarm information, including selecting the vibration motor, setting the vibration waveform, and calculating the frequency and intensity, and generates control instructions, which are transmitted to the tactile driver through the I2C multiplexer to complete the vibration parameter configuration;

[0081] (5) To achieve synchronous start of audio and tactile signals, the microprocessor simultaneously activates the external trigger pin of the tactile driver and starts the timer interrupt. The timer generates a clock signal to control the FIFO buffer to output the audio signal. After the preset time is reached, the trigger pin is set to a low level and the timer interrupt is turned off, ensuring that the audio and tactile signals end synchronously.

[0082] (6) The spatial audio signal output from the FIFO buffer is converted into an analog signal by a D / A converter, amplified by an audio amplifier, and finally transmitted to an audio output device to complete the output of the spatial audio alarm;

[0083] (7) While the audio signal is being output, the tactile feedback module activates the linear motor array on the belt according to the set vibration parameters, providing vibration feedback corresponding to the danger direction, thereby achieving synchronous auditory and tactile alarms;

[0084] (8) The microprocessor continuously monitors the output status of the audio and tactile feedback signals, dynamically adjusts the parameters of the two to ensure the accuracy and consistency of the alarm signal, and collects user feedback data for subsequent optimization and performance improvement of the system.

[0085] The danger alarm information in step (1) of the present invention includes the direction of the threat (θ, φ), where θ represents the angle in the horizontal direction, measured clockwise from the left ear, and φ represents the angle in the vertical direction, measured upward from the horizontal plane, as well as the distance d and the threat type E;

[0086] The microprocessor analyzes the information, determines its priority, and creates a data storage space Buf in the memory to store the information, waiting for use in subsequent audio and tactile signal synthesis.

[0087] The step (2) of the present invention specifically includes: calling the corresponding preset audio sample A from the memory s (t), unprocessed mono audio signal, representing a specific warning sound effect, and head-related transfer function (HRTF) dataset, used to generate spatial audio S stereo (t):

[0088] The audio sample As(t) is transformed by Fourier Convert to frequency domain representation As(ω):

[0089]

[0090] Combined with the left and right ear HRTF frequency domain data (H L (ω),H R (ω)), and perform convolution calculations respectively to obtain the left and right ear signals in the frequency domain:

[0091] S L (ω)=A s (ω)·H L (ω)

[0092] S R (ω)=A s (ω)·H R (ω)

[0093] The frequency domain signals S of the left and right ears L (ω) and S R (ω) is obtained by inverse Fourier transform Convert back to the time domain:

[0094]

[0095] The audio signals of the left and right ears are combined into a two-channel stereo signal:

[0096] S stereo (t) = [S L (t),S R (t)].

[0097] The steps of optimizing the generated spatial audio signal in step (3) of the present invention are as follows:

[0098] The interaural time difference (ITD) of binaural audio signals is dynamically adjusted based on the distance, direction and urgency of the danger source. The interaural time difference (ITD) is the time difference between the sound reaching the left and right ears due to the direction of the sound source relative to the head. The ITD can be calculated by the formula:

[0099]

[0100] Where d is the distance between the left and right ears, c is the speed of sound, θ is the horizontal angle of the sound source, and the value of cosθ is in [-1,1]. Due to ITD, the audio signal S received by the left and right ears is L (t) and S R (t) will have a time offset. To achieve synchronous output, the right ear signal S R (t) Delay compensation is required:

[0101] S stereo (t) = [S L (t),S R (t+ITD)]

[0102] The microprocessor processes the audio signal S L (t) and S R (t+ITD) is based on the sampling rate f s They are written into their respective FIFO buffers and wait for further scheduling and output.

[0103] The frequency f of the audio signal of the present invention audio =44.1kHz. According to Nyquist sampling theorem, in order to ensure better signal reproduction and leave margin, the sampling rate should be greater than twice the signal frequency. s =100kHZ.

[0104] In step (4) of the present invention, the microprocessor determines the activation mode of the tactile motor array according to the stored danger alarm information, specifically including selecting the motor number of the vibration, the waveform of the motor vibration, calculating the frequency and intensity of the vibration, generating an instruction for controlling the tactile driver, and transmitting the instruction to the tactile driver through the multiplexer to set the vibration parameters;

[0105] The microprocessor selects the motor Mi to be activated, sends a control channel I2C command to the multiplexer Mux, and the multiplexer controls the opening of the channel Ch.i corresponding to the selected linear motor Mi;

[0106] After selecting the channel, the microprocessor sends a tactile alarm instruction to the target tactile driver through the channel. The instruction sets the waveform register, frequency register, intensity register, play time register, and start register of the tactile driver. This method controls the vibration parameters of the tactile alarm signal: waveform, frequency f haptic , Amplitude A vi , time t, when the waveform is a sinusoidal signal, the tactile signal expression is:

[0107] V i (t) = A vi ·sin(2πf i t).

[0108] The method for realizing synchronous start of audio and tactile signals in step (5) of the present invention is that the microprocessor activates the external trigger pin of the configured tactile driver; the audio signals of the left and right ears are activated at f s =100 kHz sampling rate is stored in two FIFO buffers respectively. The microprocessor configures a timer, and the interrupt period of the timer is set to T clk =10μs. Each time the timer interrupt is triggered, the microprocessor enters the interrupt service routine ISR and switches the FIFO_clk pin level: the FIFO_clk pin switches from low level to high level and then switches back to low level to generate a complete clock pulse. When each clock pulse arrives, the two FIFO buffers output the left ear signal S respectively. L (t) and the right ear compensation signal S R (t+ITD) from a sampling point to the subsequent audio driving circuit to ensure the time consistency of the left and right ear audio signals;

[0109] Microprocessor synchronous alarm: When the alarm moment comes, the microprocessor sets these four pins to high level, and the corresponding numbered tactile driver immediately performs tactile alarm according to the set vibration parameters. When the tactile alarm is turned on, the timer interrupt loop is started to generate the FIFO_clk clock signal to control the FIFO buffer to output the alarm space audio;

[0110] The spatial audio signal is output by the parallel FIFO buffer controlled by the timer interrupt, and the tactile alarm signal is output by controlling the tactile driver to drive the motor. After the alarm starts for a period of time Ts, the external trigger pin level of the tactile driver is restored to a low level, and the timer loop is closed at the same time to achieve the synchronous termination of the audio signal and the tactile signal.

[0111] In order to make the objects, features and advantages of the present invention more clearly understood, the following detailed description is given with reference to the accompanying drawings.

[0112] The present invention provides an alarm device integrating spatial audio and belt-type tactile feedback, the overall physical composition of which is as follows: Figure 1 As shown, including:

[0113] The control unit 1 integrates a microprocessor, a memory, a wireless communication module, an audio drive circuit, a motor drive circuit and a power supply system. It is responsible for receiving danger information, generating and outputting spatial audio containing directional information, and controlling the linear motor array to transmit tactile feedback warnings.

[0114] The audio device 2 is used to output a spatial audio signal to help the user perceive the source direction and danger type of the alarm through hearing.

[0115] The tactile belt 3 is embedded with multiple tactile motors for providing directional vibration feedback, helping the user to perceive the urgency and direction of the alarm through touch.

[0116] Figure 2 This is a principle block diagram of the present invention, in which the wireless communication module receives external danger information, including but not limited to: danger direction (such as left front, left upper rear or right lower), danger type (such as incoming objects, obstacles or other potential threats), and driving environment (such as environmental conditions, weather conditions, etc.). The wireless communication module ensures that the information can be transmitted stably and in real time through Bluetooth, Wi-Fi or other wireless communication protocols.

[0117] Figure 2 In the device, the microprocessor, as the core of the whole device, undertakes many functions: receiving and processing the danger information provided by the external sensor, classifying the information as a threat; communicating with the memory, calling the preset audio samples and head-related transfer function (HRTF) data, and generating a spatial audio signal with a sense of direction; generating a tactile feedback parameter signal to control the waist linear motor array according to the location and severity of the danger; ensuring the synchronous output of audio and tactile signals, accurately controlling through a unified clock source, and having a dynamic adjustment function to provide accurate and synchronous multi-sensory alarm feedback. Therefore, the microprocessor needs to use a high-performance ARM or DSP digital signal processor to ensure processing efficiency and response speed.

[0118] Figure 2 In the memory, the storage audio samples and HRTF data sets used to generate spatial audio are stored; after the microprocessor generates spatial audio, it is stored in the divided audio data storage space; the tactile feedback parameters generated by the microprocessor are also stored in the divided tactile data storage space, waiting to be further scheduled and output by the microprocessor together with the spatial audio. The memory should be a large-capacity ROM or external memory.

[0119] Figure 2 In the system, the power supply system provides a stable and reliable power supply for the operation of the alarm device, ensuring normal operation under various operating conditions and usage scenarios. The system can be powered by a rechargeable lithium battery or AC power, and the power mode can be flexibly selected according to the application scenario. Rechargeable lithium batteries are suitable for mobile or portable scenarios and provide long-term endurance; AC power supply is suitable for continuous operation in a fixed environment, ensuring that the device can maintain stable operation for a long time and meet high-frequency alarm requirements.

[0120] The principle block diagram of the audio driver circuit is as follows: Figure 3As shown in the figure, the microprocessor first transmits the spatial audio signals of the left and right ear channels to two FIFO buffers respectively. After the output CLK pin of the FIFO buffer receives the clock signal, it transmits the data to the D / A converter according to the frequency of the clock signal to convert the digital signal to the analog signal. The analog audio signal after the digital-to-analog conversion is then transmitted to the audio amplifier, which amplifies the analog signal to a sufficient level to ensure that the signal can provide the user with a clear and realistic spatial audio experience when passing through the audio output device. In order to ensure high-quality audio output, the D / A conversion chip should use a high-performance, low-latency model, the audio amplifier should use a low-distortion stereo audio amplifier chip, and the audio output device should use stereo headphones to ensure the accuracy and real-time performance of the audio signal.

[0121] The principle of tactile driving circuit is as follows Figure 4 As shown in the figure, the microprocessor is connected to 12 haptic controllers through an I2C multiplexer, and each haptic controller is responsible for controlling a linear motor (number 1 to 12). The I2C address of the haptic driver usually has two options. The I2C multiplexer can communicate with multiple haptic drivers, and the control signal is transmitted to the corresponding haptic driver to set the vibration parameters of the corresponding linear motor. The PA1 to PA12 pins of the microprocessor are connected to the external trigger pins of the haptic drivers numbered 1 to 12, respectively, and the haptic driver is activated and closed by setting the high and low levels of the pins. The microprocessor generates targeted vibration feedback through the work of the haptic driver, providing users with accurate direction prompts. In order to achieve efficient and accurate vibration control, the haptic controller uses a high-performance, low-power driver chip, such as DRV2605, which supports multiple vibration modes and signal inputs. The I2C multiplexer can use an eight-channel multiplexer such as TCA9548A, which can mount up to 16 haptic drivers, which can meet the communication needs of 12 motors.

[0122] Figure 5 The distribution of the linear motor array used to achieve tactile feedback is shown. In order to take into account both wearing comfort and performance, the present invention uses a small linear motor with a size of 22.6mm×10.0mm×9.0mm. The motor arrangement structure is as follows: every two linear motors form a column, and the columns are evenly spaced on the horizontal 360° belt, with a column arranged every 60°, for a total of 6 columns. The upper and lower motors in the column are kept at a distance of 10 to 15 cm. This arrangement method can not only ensure the reasonable distribution of the motors on the belt, but also meet the resolution requirements of the human body for tactile perception, thereby providing users with a good direction indication effect, so that the dangerous direction can be intuitively presented through vibration feedback.

[0123] The vibration response curve of the linear motor is as follows: Figure 6As shown, its vibration intensity (vibration acceleration) reaches a peak at around 170Hz. In order to achieve different levels of danger warnings, the system divides the vibration intensity of the linear motor into two modes: strong vibration and weak vibration by setting specific duty cycles and frequencies. When the danger level is low, the system uses weak vibration and selects a lower vibration frequency (80Hz to 120Hz) to deliver a milder warning signal to the user. When the danger level is high, the system uses strong vibration and selects a higher vibration frequency (160Hz to 200Hz) to produce a more significant warning signal, thereby effectively attracting the user's attention and prompting them to respond in time. Through this frequency adjustment mechanism, the system can provide differentiated vibration feedback according to different alarm levels, ensuring that users can quickly perceive and take countermeasures.

[0124] In order to more clearly express the correspondence between the vibration feedback of the microprocessor-controlled linear motor and the hazard position, the system Figure 7 The linear motor array scheme is used to issue an alarm, and each motor is responsible for sensing a different direction. When implementing this scheme, the user needs to place the column where motor 3 and motor 4 are located at the navel position in front when wearing the belt to ensure that all motors can accurately transmit feedback according to the direction of danger. When a danger is detected, the system activates the corresponding motor according to the direction of the danger and provides strong or weak vibration feedback. At a high danger level, the motor vibrates strongly at a higher frequency; at a low danger level, the system selects a weak vibration at a lower frequency. In addition, the system can also combine multiple motors to vibrate simultaneously according to the direction from which the danger comes, providing more accurate direction indications. Through this multi-motor synchronous operation, the user can sense the direction and urgency of the danger through the vibration on the belt.

[0125] The present invention provides an alarm method integrating spatial audio and tactile feedback, and the specific implementation methods are as follows:

[0126] (1) The microprocessor receives danger alarm information from the environmental sensor through the wireless communication module. This information includes the direction of the threat (θ, φ) (θ represents the horizontal angle, starting from the left ear and measured clockwise. φ represents the vertical angle, measured upward from the horizontal plane), distance d, and threat type E.

[0127] The microprocessor analyzes the information, determines its priority, and creates a data storage space Buf in the memory to store the information, waiting for use in subsequent audio and tactile signal synthesis.

[0128] (2) Based on the analysis of the danger warning information in step (1), the microprocessor calls the corresponding preset audio sample A from the memory s(t) (unprocessed mono audio signal, representing a specific warning sound effect) and head-related transfer function (HRTF) dataset. Used to generate spatial audio S stereo (t):

[0129] The audio sample As(t) is transformed by Fourier Convert to frequency domain representation As(ω):

[0130]

[0131] Combined with the left and right ear HRTF frequency domain data (H L (ω),H R (ω)), and perform convolution calculations respectively to obtain the left and right ear signals in the frequency domain:

[0132] S L (ω)=A s (ω)·H L (ω)

[0133] S R (ω)=A s (ω)·H R (ω)

[0134] The frequency domain signals S of the left and right ears L (ω) and S R (ω) is obtained by inverse Fourier transform Convert back to the time domain:

[0135]

[0136] The audio signals of the left and right ears are combined into a two-channel stereo signal:

[0137] S stereo (t) = [S L (t),S R (t)]

[0138] (3) The microprocessor further optimizes the spatial audio signal generated in step (2) by dynamically adjusting the interaural time difference of the binaural audio signal based on the distance, direction and urgency of the hazard source. The interaural time difference (ITD) is the time difference between the sound reaching the left and right ears due to the direction of the sound source relative to the head. ITD can be calculated by the formula

[0139]

[0140] Where d is the distance between the left and right ears, c is the speed of sound, and θ is the horizontal angle of the sound source. The value of cosθ is in [-1,1], so ITD can be positive or negative. Due to ITD, the audio signal S received by the left and right ears isL (t) and S R (t) will have a time offset. For the convenience of describing the method, assume that the threat azimuth is θ∈[-30°,30°], which is the left direction of the user. In this case, ITD is a positive number.

[0141] To achieve synchronous output, the right ear signal S R (t) Delay compensation is required:

[0142] S stereo (t) = [S L (t),S R (t+ITD)]

[0143] The microprocessor processes the audio signal S L (t) and S R (t+ITD) is based on the sampling rate f s The audio signals are written into their respective FIFO buffers and wait for further scheduling and output. audio =44.1kHz. According to Nyquist sampling theorem, in order to ensure better signal reproduction and leave margin, the sampling rate should be greater than twice the signal frequency. s =100kHZ.

[0144] (4) The microprocessor performs the following operations according to the danger alarm information stored in step (1). Figure 7 The proposed scheme determines the activation mode of the tactile motor array, including selecting the vibration motor number, the waveform of the motor vibration, calculating the frequency and intensity of the vibration, generating instructions for controlling the tactile driver, and passing the instructions to the tactile driver through a multiplexer to set the vibration parameters.

[0145] Figure 8 The operation timing diagram of the I2C multiplexer is shown. The microprocessor selects the motor Mi to be activated and sends a control channel I2C command to the multiplexer Mux. The multiplexer controls the opening of the channel Ch.i corresponding to the selected linear motor Mi.

[0146] After selecting a channel, the microprocessor sends a tactile alarm instruction to the target tactile driver through the channel. The instruction sets the waveform register, frequency register, intensity register, play time register, and start register of the tactile driver. This method controls the vibration parameters (waveform, frequency f haptic , Amplitude A vi , time t). When the waveform is a sinusoidal signal, the tactile signal expression is:

[0147] V i (t) = A vi ·sin(2πf i t)

[0148] (5) In order to achieve synchronous start of audio and tactile signals, the microprocessor activates the external trigger pin of the tactile driver configured in step (4). Figure 4 As shown in FIG. 1 , the microprocessor's PA1 to PA12 pins are connected to the external trigger pins of the tactile drivers numbered 1 to 12, respectively, and the tactile drivers are activated or deactivated by setting the high and low levels of the pins. Assuming that the azimuth angle of the threat is θ∈[-30°,30°], that is, the left direction of the user, according to Figure 7 The motor array coding scheme determines that the tactile drivers that need to be activated are numbered 1, 2, 7, and 8, and the corresponding microprocessor pins set to high level are PA1, PA2, PA7, and PA8.

[0149] The left and right ear spatial audio signals are expressed as f in step (3). s = 100 kHz sampling rate is stored in two FIFO buffers, such as Figure 3 A certain pin of the microprocessor shown is used as a clock signal output pin FIFO_clk and is connected to the CLK pins of the two FIFO buffers.

[0150] The microprocessor configures a timer, and the interrupt period of the timer is set to T clk = 10μs. Each time the timer interrupt is triggered, the microprocessor enters the interrupt service routine (ISR) and switches the FIFO_clk pin level: the FIFO_clk pin switches from low level to high level and then switches back to low level to generate a complete clock pulse. When each clock pulse arrives, the two FIFO buffers output the left ear signal S respectively. L (t) and the right ear compensation signal S R The audio signal from the left ear to the right ear is synchronized with the audio signal from the right ear to the left ear.

[0151] In each 10μs interrupt cycle, the FIFO buffer outputs a sampling point to the audio driver circuit. This method ensures that the audio signal can be output stably at a frequency of 100kHz.

[0152] The synchronous alarm timing of the microprocessor is as follows Fig. 9 As shown, when the alarm moment arrives, the microprocessor sets these four pins to a high level, and the corresponding numbered tactile drivers immediately perform a tactile alarm according to the vibration parameters set in step (4). When the tactile alarm is turned on, the timer interrupt loop is started to generate a FIFO_clk clock signal to control the FIFO buffer to output the alarm spatial audio.

[0153] The spatial audio signal is output by the parallel FIFO buffer controlled by the timer interrupt, and the tactile alarm signal is output by controlling the tactile driver to drive the motor. After the alarm starts for a period of time Ts, the external trigger pin level of the tactile driver is restored to a low level, and the timer loop is closed at the same time to achieve the synchronous termination of the audio signal and the tactile signal.

[0154] (6) The spatial audio signal output by the FIFO buffer in step (5) enters the audio driving circuit, is converted into an analog audio signal by a D / A converter, and then is amplified by an audio amplifier and transmitted to an audio output device to provide a spatial audio alarm to the user.

[0155] (7) While step (6) is being performed, the tactile feedback module activates the linear motor array on the belt according to the vibration parameter instruction set in step (4), so that it generates vibration feedback matching the danger direction, giving the user tactile feedback alarm information synchronized with the hearing.

[0156] (8) The microprocessor monitors the output of audio and tactile feedback signals in real time and dynamically adjusts the parameters of both to ensure the accuracy and consistency of the alarm signal, so that users can receive danger alarm information in a timely and accurate manner. The system also collects user feedback data and stores it for system optimization and performance improvement.

[0157] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An alarm device integrating spatial audio and belt-type tactile feedback, characterized in that: It includes a microprocessor, a wireless communication module, a memory, an audio drive circuit, a tactile drive circuit, a tactile feedback belt, an audio device and a power supply system; The microprocessor is responsible for receiving danger information sent by external sensors, analyzing data such as danger location and urgency, and generating and outputting corresponding spatial audio signals and tactile feedback signals; The wireless communication module receives danger alarm information from the environment in real time via Bluetooth or other wireless protocols and transmits it to the microprocessor; The memory is used to store audio samples, head-related transfer function HRTF data sets and tactile feedback parameters, and the microprocessor calls these data to generate spatial audio signals; The audio driving circuit includes a FIFO buffer, a D / A converter and an audio amplifier, which are used to convert digital audio signals into analog signals and amplify them into audio signals suitable for output through headphones or speakers; The tactile drive circuit comprises an I2C multiplexer and a tactile driver, which is used to receive tactile instructions from a microprocessor, generate a vibration signal to drive the tactile feedback belt to produce a vibration tactile alarm; The tactile feedback belt includes a linear motor array that generates vibration signals through a microprocessor-controlled tactile drive circuit to provide directional tactile feedback to indicate the source of danger; The audio device includes headphones or speakers, which are used to output spatial audio signals to help users perceive the source direction and danger type of the alarm through hearing; The power supply system provides stable power to all components and supports power supply from rechargeable lithium batteries or AC power supply.

2. An alarm method integrating spatial audio and belt-type tactile feedback, characterized in that: The following steps are involved: (1) The microprocessor controls the wireless communication module to receive danger alarm information from environmental sensors, analyze data of different danger levels and sources, determine their priorities, and create dedicated storage space in the memory for each alarm information for subsequent processing and retrieval; (2) Based on the stored danger alarm information, the microprocessor calls the audio samples and the head-related transfer function (HRTF) data set to generate a spatial audio signal related to the direction of the danger source. Through the HRTF technology, the user can clearly perceive the danger direction through stereo headphones; (3) The microprocessor further optimizes the generated spatial audio signal and dynamically adjusts the interaural time difference of the audio signal according to the distance and direction of the danger source to ensure that the user accurately perceives the danger location and urgency. The optimized binaural audio signal is stored in a FIFO buffer at a fixed sampling rate for subsequent scheduling and output; (4) The microprocessor determines the tactile feedback mode according to the danger alarm information, including selecting the vibration motor, setting the vibration waveform, and calculating the frequency and intensity, and generates control instructions, which are transmitted to the tactile driver through the I2C multiplexer to complete the vibration parameter configuration; (5) To achieve synchronous start of audio and tactile signals, the microprocessor simultaneously activates the external trigger pin of the tactile driver and starts the timer interrupt. The timer generates a clock signal to control the FIFO buffer to output the audio signal. After the preset time is reached, the trigger pin is set to a low level and the timer interrupt is turned off, ensuring that the audio and tactile signals end synchronously. (6) The spatial audio signal output from the FIFO buffer is converted into an analog signal by a D / A converter, amplified by an audio amplifier, and finally transmitted to an audio output device to complete the output of the spatial audio alarm; (7) While the audio signal is being output, the tactile feedback module activates the linear motor array on the belt according to the set vibration parameters, providing vibration feedback corresponding to the danger direction, thereby achieving synchronous auditory and tactile alarms; (8) The microprocessor continuously monitors the output status of the audio and tactile feedback signals, dynamically adjusts the parameters of the two to ensure the accuracy and consistency of the alarm signal, and collects user feedback data for subsequent optimization and performance improvement of the system.

3. The warning method integrating spatial audio and belt-type tactile feedback according to claim 2 is characterized in that: The danger alarm information in step (1) includes the direction of the threat (θ, φ), where θ represents the angle in the horizontal direction, measured clockwise from the left ear, and φ represents the angle in the vertical direction, measured upward from the horizontal plane, as well as the distance d and the threat type E; The microprocessor analyzes the information, determines its priority, and creates a data storage space Buf in the memory to store the information, waiting for use in subsequent audio and tactile signal synthesis.

4. The alarm method integrating spatial audio and belt-type tactile feedback according to claim 2, characterized in that: The step (2) specifically includes: calling the corresponding preset audio sample A from the memory s (t), unprocessed mono audio signal, representing a specific warning sound effect, and head-related transfer function (HRTF) dataset, used to generate spatial audio S stereo (t): The audio sample As(t) is transformed by Fourier Convert to frequency domain representation As(ω): Combined with the left and right ear HRTF frequency domain data (H L (ω),H R (ω)), and perform convolution calculations respectively to obtain the left and right ear signals in the frequency domain: S L (ω)=A s (ω)·H L (oh) S R (ω)=A s (ω)·H R (oh) The frequency domain signals S of the left and right ears L (ω) and S R (ω) is obtained by inverse Fourier transform Convert back to the time domain: The audio signals of the left and right ears are combined into a two-channel stereo signal: S stereo (t)=[S L (t),S R (t)]。 5. The alarm method integrating spatial audio and belt-type tactile feedback according to claim 2, characterized in that: The steps of optimizing the generated spatial audio signal in step (3) are as follows: The interaural time difference (ITD) of binaural audio signals is dynamically adjusted based on the distance, direction and urgency of the danger source. The interaural time difference (ITD) is the time difference between the sound reaching the left and right ears due to the direction of the sound source relative to the head. The ITD can be calculated by the formula: Where d is the distance between the left and right ears, c is the speed of sound, θ is the horizontal angle of the sound source, and the value of cosθ is in [-1,1]. Due to ITD, the audio signal S received by the left and right ears is L (t) and S R (t) will have a time offset. To achieve synchronous output, the right ear signal S R (t) Delay compensation is required: S stereo (t)=[S L (t),S R (t+ITD)] The microprocessor processes the audio signal S L (t) and S R (t+ITD) is based on the sampling rate f s They are written into their respective FIFO buffers and wait for further scheduling and output.

6. The alarm method integrating spatial audio and belt-type tactile feedback according to claim 5, characterized in that: The frequency f of the audio signal audio =44.1kHz. According to Nyquist sampling theorem, in order to ensure better signal reproduction and leave margin, the sampling rate should be greater than twice the signal frequency. s =100kHZ.

7. The alarm method integrating spatial audio and belt-type tactile feedback according to claim 2, characterized in that: In step (4), the microprocessor determines the activation mode of the tactile motor array according to the stored danger alarm information, specifically including selecting the motor number of the vibration, the waveform of the motor vibration, calculating the frequency and intensity of the vibration, generating an instruction for controlling the tactile driver, and transmitting the instruction to the tactile driver through the multiplexer to set the vibration parameters; The microprocessor selects the motor Mi to be activated, sends a control channel I2C command to the multiplexer Mux, and the multiplexer controls the opening of the channel Ch.i corresponding to the selected linear motor Mi; After selecting the channel, the microprocessor sends a tactile alarm instruction to the target tactile driver through the channel. The instruction sets the waveform register, frequency register, intensity register, play time register, and start register of the tactile driver. This method controls the vibration parameters of the tactile alarm signal: waveform, frequency f haptic , Amplitude A vi , time t, when the waveform is a sinusoidal signal, the tactile signal expression is: V i (t)=A vi ·sin(2πf i t)。 8. The alarm method integrating spatial audio and belt-type tactile feedback according to claim 2, characterized in that: The method for realizing synchronous start of audio and tactile signals in step (5) is that the microprocessor activates the external trigger pin of the configured tactile driver; the audio signals of the left and right ears are activated at f s =100 kHz sampling rate is stored in two FIFO buffers respectively. The microprocessor configures a timer, and the interrupt period of the timer is set to T clk =10μs. Each time the timer interrupt is triggered, the microprocessor enters the interrupt service routine ISR and switches the FIFO_clk pin level: the FIFO_clk pin switches from low level to high level and then switches back to low level to generate a complete clock pulse. When each clock pulse arrives, the two FIFO buffers output the left ear signal S respectively. L (t) and the right ear compensation signal S R (t+ITD) from a sampling point to the subsequent audio driving circuit to ensure the time consistency of the left and right ear audio signals; Microprocessor synchronous alarm: When the alarm moment comes, the microprocessor sets these four pins to high level, and the corresponding numbered tactile driver immediately performs tactile alarm according to the set vibration parameters. When the tactile alarm is turned on, the timer interrupt loop is started to generate the FIFO_clk clock signal to control the FIFO buffer to output the alarm space audio; The spatial audio signal is output by the parallel FIFO buffer controlled by the timer interrupt, and the tactile alarm signal is output by controlling the tactile driver to drive the motor. After the alarm starts for a period of time Ts, the external trigger pin level of the tactile driver is restored to a low level, and the timer loop is closed at the same time to achieve the synchronous termination of the audio signal and the tactile signal.

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