Safety belt dynamic adjusting method based on distributed optical fiber sensing

Abstract

The invention discloses a safety belt dynamic adjustment method based on distributed optical fiber sensing, and relates to the technical field of vehicle safety, and the method comprises the steps: deploying a distributed optical fiber sensor array, collecting optical signal phase change data in the length direction of a safety belt, and carrying out the preprocessing of the data, and obtaining the preprocessed safety belt strain distribution data; identifying a collision event based on the calculated standard deviation and the spatial gradient of the preprocessed safety belt strain distribution data, and determining a dynamic adjustment mode of the safety belt; and according to the dynamic adjustment mode, driving the motor to execute adjustment operation in the response period, calculating a safety belt displacement error, and triggering dynamic adjustment mode switching according to the safety belt displacement error. According to the method, collision events are rapidly distinguished, the restraint force and the collision situation of the passenger can be dynamically matched, the physiological safety of the passenger is guaranteed, and accurate restraint of the safety belt is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle safety, in particular to a seat belt dynamic adjustment method based on distributed optical fiber sensing. Background Art

[0002] With the continuous evolution of active vehicle safety technologies, the performance optimization and intelligent upgrade of seatbelts, as a crucial component of the occupant restraint system, have become a hot topic of research. Traditional passive seatbelts restrain occupant displacement through mechanical force limiters and pretensioners, but they rely primarily on acceleration sensors or vehicle collision pulse signals to trigger pretensioning. This pretensioning strategy, based on vehicle acceleration or airbag control module (ACM) output signals, only applies after a collision has occurred. The pretensioning force is poorly coupled to the specific collision load profile, making it difficult to adaptively adjust to different collision directions and occupant body shapes. With the mature application of fiber optic sensing technology in structural health monitoring, medical diagnostics, and intelligent manufacturing, distributed fiber optic sensors are beginning to be incorporated into automotive safety systems due to their high spatial resolution and multi-point online real-time monitoring capabilities. Some research has explored the use of fiber optic strain measurement for vibration and deformation monitoring of vehicle body structures and seat frames, but its application to seatbelt strain distribution is still in its early stages of exploration. At the same time, traditional pre-tensioning devices mostly have single-stage or fixed-stage responses and can only provide approximate bandwidth and torque control. They lack the fine perception of the strain field along the seat belt surface and the feedback closed-loop adjustment capability based on perception, resulting in problems of delayed, excessive or insufficient adjustment in the dynamic restraint process.

[0003] In existing technologies, although active seatbelt systems can trigger pretensioning or force limiting based on collision events, their perception and execution are often separated, making it impossible to obtain real-time strain gradient information on the seatbelt in different areas such as the shoulder and waist. There is also a lack of control algorithms that directly link strain distribution characteristics with adjustment modes. In addition, single-point strain sensors or pressure sensing devices are easily affected by differences in installation position and occupant body shape, resulting in significant measurement blind spots. Similarly, gas-driven pretensioners are limited in response speed and adjustment levels, making it difficult to meet the requirements of multi-level fine-tuning at the millisecond level. As a result, under different collision directions and complex in-vehicle operating conditions, the seatbelt's restraint force on occupant displacement cannot be accurately matched, posing the risk of being too loose or too tight, making it difficult to meet the dual requirements of structural safety and occupant physiological safety. Summary of the Invention

[0004] In view of the problems existing in the existing seat belt dynamic adjustment method based on distributed optical fiber sensing, the present invention is proposed. Therefore, the problem to be solved by the present invention is how to provide a seat belt dynamic adjustment method based on distributed optical fiber sensing.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] In a first aspect, the present invention provides a seat belt dynamic adjustment method based on distributed optical fiber sensing, which includes deploying a distributed optical fiber sensor array to collect optical signal phase change data along the length of the seat belt and preprocessing the data to obtain preprocessed seat belt strain distribution data;

[0007] Identify crash events based on the calculated standard deviation and spatial gradient of pre-processed seat belt strain distribution data and determine the dynamic adjustment mode of the seat belt;

[0008] According to the dynamic adjustment mode, the motor is driven to perform adjustment operations respectively within the response cycle, and the seat belt displacement error is calculated, and the dynamic adjustment mode switching is triggered according to the seat belt displacement error.

[0009] As a preferred solution of the seat belt dynamic adjustment method based on distributed optical fiber sensing described in the present invention, the preprocessing includes demodulating and sliding window filtering the collected optical signal phase change data to convert the optical signal phase change data into seat belt strain distribution data.

[0010] As a preferred embodiment of the seat belt dynamic adjustment method based on distributed optical fiber sensing of the present invention, the method of identifying a collision event based on the calculated standard deviation and spatial gradient of the pre-processed seat belt strain distribution data includes:

[0011] Perform strain standard deviation calculation and calculate the strain standard deviation in the length direction of the seat belt, which is expressed as:

[0012] ;

[0013] in, is the strain standard deviation, is the average strain; For the The strain value corresponding to the sensor number is is the total number of sensors;

[0014] Obtain the collision trigger threshold. When the strain standard deviation is greater than the collision trigger threshold, it is determined that a collision event has occurred and the collision type identification process begins; otherwise, continue monitoring.

[0015] Get the corresponding coordinates of the sensor and calculate the distance between adjacent sensors. The formula is:

[0016] ;

[0017] in, is the distance between adjacent sensors, For sensors +1 corresponds to the coordinate; For sensors Corresponding coordinates;

[0018] Calculate the discrete spatial gradient of strain, expressed as:

[0019] ;

[0020] in, For the Sensor No. + Discrete spatial gradient between sensors 1, For the +The strain value corresponding to sensor No. 1;

[0021] Divide the shoulder area and waist area, and set the coordinate interval corresponding to the shoulder area ; The coordinate interval corresponding to the waist area ;

[0022] The gradient peak of the divided area is extracted, and the collision event is triggered according to the gradient threshold.

[0023] As a preferred solution of the seat belt dynamic adjustment method based on distributed optical fiber sensing of the present invention, the triggering and determining of a collision event based on a gradient threshold includes:

[0024] Extract the gradient peak value of the divided area, obtain the maximum strain gradient of the shoulder and the maximum strain gradient of the waist; obtain the gradient trigger threshold of the shoulder and the waist;

[0025] If, at the moment of the collision event, the maximum strain gradient of the shoulder is greater than the shoulder gradient trigger threshold, it is determined to be a frontal collision and the first dynamic adjustment mode is activated;

[0026] If the maximum strain gradient of the waist is greater than the waist gradient trigger threshold, it is determined to be a side collision and the second dynamic adjustment mode is activated;

[0027] If the maximum strain gradient of the shoulder does not exceed the shoulder gradient trigger threshold and the maximum strain gradient of the waist does not exceed the waist gradient trigger threshold, the original state is maintained and no dynamic adjustment of the seat belt is performed.

[0028] As a preferred embodiment of the seat belt dynamic adjustment method based on distributed optical fiber sensing of the present invention, the driving of the motor to perform adjustment operations respectively within a response period according to the dynamic adjustment mode includes:

[0029] Obtain the real-time regional gradient peak, the initial buckle displacement and the maximum allowable displacement of the seat belt, and set the response period; calculate the shoulder gradient error and waist gradient error, which can be expressed as:

[0030] ;

[0031] ;

[0032] in, is the shoulder gradient error, is the waist gradient error, For the shoulder area Maximum strain gradient at time t; For the waist area Maximum strain gradient at time t; is the shoulder gradient trigger threshold, The trigger threshold for the waist gradient;

[0033] Calculate the thoracic pressure attenuation coefficient, expressed as:

[0034] ;

[0035] in, is the thoracic pressure attenuation coefficient, Real-time chest pressure of the occupant; To withstand the maximum pressure; is the pressure responsiveness index;

[0036] The single-step displacement increment under different dynamic adjustment modes is obtained according to the shoulder gradient error, waist gradient error and thoracic pressure attenuation coefficient.

[0037] As a preferred solution of the seat belt dynamic adjustment method based on distributed optical fiber sensing of the present invention, the calculation of the seat belt displacement error includes:

[0038] The target displacement of the seat belt is calculated according to the dynamic adjustment mode. The target displacement of the seat belt is expressed as:

[0039] ;

[0040] in, is the target displacement of the seat belt, is the actual displacement after the previous iteration, is the initial buckle displacement of the seat belt, is the single-step displacement increment of the first dynamic adjustment mode, is the single-step displacement increment of the second dynamic adjustment mode; is the first dynamic adjustment mode, is the second dynamic adjustment mode;

[0041] During the response period, the bidirectional linear motor is driven toward the target displacement of the seat belt at a constant speed or a preset acceleration curve. The real-time displacement of the seat belt is obtained through the sensor, and the displacement error is calculated and expressed as:

[0042] ;

[0043] in, is the displacement error, For the The actual response displacement of the stage.

[0044] As a preferred solution of the seat belt dynamic adjustment method based on distributed optical fiber sensing of the present invention, the triggering of dynamic adjustment mode switching according to seat belt displacement error includes:

[0045] If the absolute value of the displacement error Displacement convergence tolerance When the displacement exceeds the maximum allowable travel, the system stops driving and triggers the hydraulic buffer.

[0046] If the dynamic adjustment mode is the first dynamic adjustment mode and the occupant's real-time chest pressure exceeds the chest pressure safety threshold, the tightening is immediately interrupted and the second dynamic adjustment mode is switched to. After the adjustment is completed, the cycle is exited.

[0047] If the absolute value of the displacement error >Displacement convergence tolerance When, update for , enter the next level loop.

[0048] In a second aspect, the present invention provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein when the processor executes the computer program, the steps of a seat belt dynamic adjustment method based on distributed optical fiber sensing are implemented.

[0049] In a third aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the steps of a seat belt dynamic adjustment method based on distributed optical fiber sensing are implemented.

[0050] The beneficial effects of this invention include: This method enables high-resolution temporal and spatial measurement of strain at various locations on the seatbelt; accurately captures the strain distribution characteristics of the belt surface, improving sensing accuracy and eliminating single-point measurement blind spots and noise interference. It also enables rapid differentiation of collision events, improving sensitivity, shortening response delays, and enhancing system robustness. By performing multi-stage tightening or loosening operations based on different adjustment modes and calculating seatbelt displacement errors in real time to trigger mode switching, it dynamically matches occupant restraint force with collision dynamics, ensuring occupant physiological safety and achieving precise seatbelt restraint. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0052] Figure 1 The figure is a flow chart of the seat belt dynamic adjustment method based on distributed optical fiber sensing of the present invention. DETAILED DESCRIPTION

[0053] To make the above-mentioned objects, features, and advantages of the present invention more easily understood, the following detailed description of the specific embodiments of the present invention is given in conjunction with the accompanying drawings. It is obvious that the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in this field without creative work should fall within the scope of protection of the present invention.

[0054] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0055] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it constitute a separate or selective embodiment that is mutually exclusive with other embodiments.

[0056] Reference Figure 1 This embodiment provides a seat belt dynamic adjustment method based on distributed optical fiber sensing, including:

[0057] S1: Deploy a distributed optical fiber sensor array along the length of the seat belt to collect and preprocess the optical signal phase change data to obtain the preprocessed seat belt strain distribution data;

[0058] Specifically, a distributed array of fiber optic sensors is deployed at equal intervals along the length of the seatbelt. Phase changes in the optical signals from each sensor are collected in real time. A demodulation algorithm converts these phase changes into strain values ​​at each seatbelt location, generating a seatbelt strain distribution dataset. This dataset is then filtered using a sliding window to eliminate high-frequency noise, resulting in preprocessed strain distribution data.

[0059] A coherent laser light source and a double-arm interferometer are selected, and the measuring optical fiber is laid in sections along the length of the seat belt. Coherent detection is performed with the reference arm in the interferometer to determine the pulse width and repetition frequency to meet the required spatial resolution and update rate.

[0060] At the receiving end, photoelectric detectors are used to obtain the in-phase and quadrature components after interference. FPGAs or high-speed sampling cards are used to collect the in-phase and quadrature component values ​​in real time according to the pulse trigger timing.

[0061] The instantaneous phase of the collected in-phase and quadrature component data is calculated using the atan2 function, and the phase unwrapping algorithm is applied to the phase sequence to obtain a continuous phase curve.

[0062] In the initial state without external loading, the baseline phase of each spatial point is recorded, and the real-time phase is subtracted from the baseline phase to obtain the phase increment;

[0063] Based on the fiber photoelastic effect theory or experimental calibration, the conversion constant is calculated or measured, the phase increment is mapped to the strain value per unit length, and resampled according to the set spatial interval.

[0064] The strain value of each sampling point is output as a one-dimensional space-time matrix or discrete curve to obtain a strain distribution data set. The strain distribution data set is subjected to sliding window filtering to eliminate high-frequency noise interference and obtain preprocessed strain distribution data.

[0065] S2: Identify crash events based on the calculated standard deviation and spatial gradient of the pre-processed seat belt strain distribution data and determine the dynamic adjustment mode of the seat belt;

[0066] Specifically, perform preliminary identification of collision events, set at time , the distributed optical fiber sensor collects a total of N pre-processed strain values ​​at locations, which are recorded as:

[0067] ;

[0068] in, For the The strain value corresponding to the sensor number is is the total number of sensors.

[0069] Calculate the strain standard deviation and calculate the strain standard deviation in the length direction of the seat belt at that moment, which is expressed as:

[0070] ;

[0071] in, is the strain standard deviation, is the average strain;

[0072] Assume that the pre-calibrated collision trigger threshold is When the strain standard deviation is greater than the collision trigger threshold, it is determined that a collision event exists and the collision type identification process begins; otherwise, monitoring continues.

[0073] To identify the collision type and distinguish between frontal collision and side collision, it is necessary to quantify the spatial gradient characteristics of strain distribution in the shoulder and waist areas.

[0074] The length coordinate of the seat belt is recorded as the z axis starting from the top of the head, and the value range is [0, L], where L is the total length of the seat belt;

[0075] sensor Corresponding coordinates , the spacing between adjacent sensors is calculated using the formula:

[0076] ;

[0077] in, is the distance between adjacent sensors, For sensors +1 corresponds to the coordinate;

[0078] Define the discrete spatial gradient of strain:

[0079] ;

[0080] in, For the Sensor No. + Discrete spatial gradient between sensors 1, For the +The strain value corresponding to sensor No. 1;

[0081] Divide the shoulder and waist areas and set the coordinate interval corresponding to the shoulder area ; The coordinate interval corresponding to the waist area .

[0082] Extract the gradient peak of the divided area and obtain the maximum strain gradient of the shoulder and the maximum strain gradient at the waist .

[0083] The collision event is determined according to the gradient trigger threshold, and the shoulder gradient trigger threshold is obtained as , the waist gradient trigger threshold is .

[0084] If the collision event is triggered When the maximum strain gradient of the shoulder is greater than the shoulder gradient trigger threshold, it is determined to be a frontal collision and the first dynamic adjustment mode is activated;

[0085] If the maximum strain gradient of the waist is greater than the waist gradient trigger threshold, it is determined to be a side collision and the second dynamic adjustment mode is activated;

[0086] If both do not exceed the trigger threshold, the original state is maintained and no dynamic adjustment of the seat belt is performed.

[0087] S3: According to the dynamic adjustment mode, the motor drives the motor to perform multi-stage tightening or loosening operations within the response cycle, triggering reverse relaxation or hydraulic buffering when the chest cavity is overpressured or the lock travel limit, realizing dynamic adjustment of the seat belt based on distributed fiber optic sensing.

[0088] Specifically, according to the determined adjustment mode, the bidirectional linear motor is driven to perform dynamic adjustment:

[0089] The dynamic adjustment mode identification is provided by the collision type identification result, which is expressed as:

[0090] ;

[0091] in, In dynamic adjustment mode, is the first dynamic adjustment mode, is the second dynamic adjustment mode;

[0092] Obtain the real-time regional gradient peak, the initial buckle displacement and the maximum allowable displacement of the seat belt, and set the response cycle;

[0093] Calculate the shoulder gradient error and waist gradient error, expressed as:

[0094] ;

[0095] ;

[0096] in, is the shoulder gradient error, is the waist gradient error, For the shoulder area Maximum strain gradient at time t; For the waist area The maximum strain gradient at time.

[0097] Calculate the thoracic pressure attenuation coefficient, expressed as:

[0098] ;

[0099] in, is the thoracic pressure attenuation coefficient, Real-time chest pressure of the occupant; To withstand the maximum pressure; It is a pressure-responsive index used to adjust the attenuation rate of the pressure level to the adjustment step.

[0100] For different dynamic adjustment modes, the same structure of PID control is used respectively, and then multiplied by the pressure attenuation coefficient and saturation suppression function, which is expressed as:

[0101] ;

[0102] ;

[0103] in, and is the unsaturated PID output, 、 and are proportional, integral, and differential gains respectively; For the response cycle.

[0104] In order to prevent a single operation from being too large, a bilateral saturation mapping function is introduced to map the single-step control amount, which can be expressed as:

[0105] ;

[0106] in, is a bilateral saturation mapping function, is the maximum tightening amount in a single step, is the maximum relaxation amount in a single step;

[0107] The final step amount is calculated to obtain the single-step displacement increment under different dynamic adjustment modes, which is expressed as:

[0108] ;

[0109] ;

[0110] in, is the single-step displacement increment of the first dynamic adjustment mode, is the single-step displacement increment of the second dynamic adjustment mode;

[0111] The number of classifications K is set according to the system bandwidth and the expected total travel. The number of classifications is the maximum number of iterations allowed in the response process of a single collision event.

[0112] For each level (1≤ ≤K) perform the following steps:

[0113] The target displacement of the seat belt is calculated according to the dynamic adjustment mode. The target displacement of the seat belt is expressed as:

[0114] ;

[0115] in, is the target displacement of the seat belt, is the actual displacement after the previous iteration, is the initial buckle displacement of the seat belt, is the first dynamic adjustment mode, is the second dynamic adjustment mode; is the single-step displacement increment of the first dynamic adjustment mode, is the single-step displacement increment of the second dynamic adjustment mode;

[0116] In the response cycle Drive the bidirectional linear motor towards the Directional movement, obtain the real-time displacement of the seat belt through the sensor, calculate the displacement error, and express it as:

[0117] ;

[0118] in, is the displacement error, For the The actual response displacement of the stage;

[0119] If the displacement error Displacement convergence tolerance When the seat belt is considered to have converged, the process starts to determine whether to trigger the safety constraint. If the actual response displacement of the seat belt exceeds the maximum allowable stroke, the drive is immediately stopped and the hydraulic buffer is triggered. If the dynamic adjustment mode is the first dynamic adjustment mode and the occupant's chest pressure exceeds the chest pressure safety threshold, the tightening is immediately interrupted and the second dynamic adjustment mode is switched to. After the adjustment is completed, the loop is exited. If the displacement error >Displacement convergence tolerance When, update for , enter the next level loop.

[0120] This embodiment also provides a computer device, which is suitable for the case of a seat belt dynamic adjustment method based on distributed optical fiber sensing, including: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute computer-executable instructions to implement all or part of the steps of the method described in the embodiment of the present invention as proposed in the above embodiment.

[0121] This embodiment also provides a storage medium having a computer program stored thereon, which, when executed by a processor, executes the method of any optional implementation of the above embodiment. The storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk, or optical disk.

[0122] The storage medium proposed in this embodiment and the data storage method proposed in the above embodiment belong to the same inventive concept. Technical details not fully described in this embodiment can be found in the above embodiment, and this embodiment has the same beneficial effects as the above embodiment.

[0123] In summary, this method achieves high-resolution temporal and spatial strain measurement at all locations on the seatbelt. It can accurately capture the strain distribution characteristics of the belt surface, improve sensing accuracy, eliminate single-point measurement blind spots and noise interference, and rapidly distinguish between collision events. This improves discrimination sensitivity, shortens response delays, and enhances system robustness.

[0124] It performs multi-level tightening or loosening operations according to different adjustment modes, and calculates the seat belt displacement error in real time to trigger mode switching. It can dynamically match the occupant restraint force with the collision situation, ensure the physiological safety of the occupant, and achieve precise restraint of the seat belt.

[0125] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A seat belt dynamic adjustment method based on distributed optical fiber sensing, characterized by: include, Deploy a distributed fiber optic sensor array along the length of the seat belt to collect and preprocess the optical signal phase change data to obtain the preprocessed seat belt strain distribution data; Identify crash events based on the calculated standard deviation and spatial gradient of pre-processed seat belt strain distribution data and determine the dynamic adjustment mode of the seat belt; According to the dynamic adjustment mode, the motor is driven to perform adjustment operations respectively within the response cycle, and the seat belt displacement error is calculated, and the dynamic adjustment mode switching is triggered according to the seat belt displacement error.

2. The seat belt dynamic adjustment method based on distributed optical fiber sensing according to claim 1, characterized in that: The preprocessing includes demodulating and performing sliding window filtering on the collected optical signal phase change data, and converting the optical signal phase change data into seat belt strain distribution data.

3. The seat belt dynamic adjustment method based on distributed optical fiber sensing according to claim 2, characterized in that: The method of identifying a collision event based on the calculated standard deviation and spatial gradient of the pre-processed seat belt strain distribution data includes: Perform strain standard deviation calculation and calculate the strain standard deviation in the length direction of the seat belt, which is expressed as: ； in, is the strain standard deviation, is the average strain; For the The strain value corresponding to the sensor number is is the total number of sensors; Obtain the collision trigger threshold. When the strain standard deviation is greater than the collision trigger threshold, it is determined that a collision event has occurred and the collision type identification process begins; otherwise, monitoring continues. Get the corresponding coordinates of the sensor and calculate the distance between adjacent sensors. The formula is: ； in, is the distance between adjacent sensors, For sensors +1 corresponds to the coordinate; For sensors Corresponding coordinates; Calculate the discrete spatial gradient of strain, expressed as: ； in, For the Sensor No. + Discrete spatial gradient between sensors 1, For the +The strain value corresponding to sensor No. 1; Divide the shoulder area and waist area, and set the coordinate interval corresponding to the shoulder area ; The coordinate interval corresponding to the waist area ; The gradient peak of the divided area is extracted, and the collision event is triggered according to the gradient threshold.

4. The seat belt dynamic adjustment method based on distributed optical fiber sensing according to claim 3, characterized in that: The triggering and determining of a collision event according to a gradient threshold comprises: Extract the gradient peak value of the divided area, obtain the maximum strain gradient of the shoulder and the maximum strain gradient of the waist; obtain the gradient trigger threshold of the shoulder and the waist; If, at the moment of the collision event, the maximum strain gradient of the shoulder is greater than the shoulder gradient trigger threshold, it is determined to be a frontal collision and the first dynamic adjustment mode is activated; If the maximum strain gradient of the waist is greater than the waist gradient trigger threshold, it is determined to be a side collision and the second dynamic adjustment mode is activated; If the maximum strain gradient of the shoulder does not exceed the shoulder gradient trigger threshold and the maximum strain gradient of the waist does not exceed the waist gradient trigger threshold, the original state is maintained and no dynamic adjustment of the seat belt is performed.

5. The seat belt dynamic adjustment method based on distributed optical fiber sensing according to claim 4, characterized in that: Driving the motor to perform adjustment operations respectively within the response period according to the dynamic adjustment mode includes: Obtain the real-time regional gradient peak, the initial buckle displacement and the maximum allowable displacement of the seat belt, and set the response period; calculate the shoulder gradient error and waist gradient error, which can be expressed as: ； ； in, is the shoulder gradient error, is the waist gradient error, For the shoulder area Maximum strain gradient at time t; For the waist area Maximum strain gradient at time t; is the shoulder gradient trigger threshold, The trigger threshold for the waist gradient; Calculate the thoracic pressure attenuation coefficient, expressed as: ； in, is the thoracic pressure attenuation coefficient, Real-time chest pressure of the occupant; To withstand the maximum pressure; is the pressure responsiveness index; The single-step displacement increment under different dynamic adjustment modes is obtained according to the shoulder gradient error, waist gradient error and thoracic pressure attenuation coefficient.

6. The seat belt dynamic adjustment method based on distributed optical fiber sensing according to claim 5, characterized in that: The calculation of the seat belt displacement error includes: The target displacement of the seat belt is calculated according to the dynamic adjustment mode. The target displacement of the seat belt is expressed as: ； in, is the target displacement of the seat belt, is the actual displacement after the previous iteration, is the initial buckle displacement of the seat belt, is the single-step displacement increment of the first dynamic adjustment mode, is the single-step displacement increment of the second dynamic adjustment mode; is the first dynamic adjustment mode, is the second dynamic adjustment mode; During the response period, the bidirectional linear motor is driven toward the target displacement of the seat belt at a constant speed or a preset acceleration curve. The real-time displacement of the seat belt is obtained through the sensor, and the displacement error is calculated and expressed as: ； in, is the displacement error, For the The actual response displacement of the stage.

7. The seat belt dynamic adjustment method based on distributed optical fiber sensing according to claim 6, characterized in that: The triggering of dynamic adjustment mode switching according to the seat belt displacement error includes: If the absolute value of the displacement error Displacement convergence tolerance When the displacement of the seat belt is greater than the maximum allowable stroke, the drive is stopped immediately and the hydraulic buffer is triggered. If the dynamic adjustment mode is the first dynamic adjustment mode and the occupant's real-time chest pressure is greater than the chest pressure safety threshold, the tightening is immediately interrupted and the second dynamic adjustment mode is entered. After the adjustment is completed, the cycle is exited. If the absolute value of the displacement error >Displacement convergence tolerance When, update for , enter the next level loop.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the seat belt dynamic adjustment method based on distributed optical fiber sensing according to any one of claims 1 to 7 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the seat belt dynamic adjustment method based on distributed optical fiber sensing according to any one of claims 1 to 7 are implemented.

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