Airbag testing method and system

Abstract

The application belongs to the technical field of vehicle safety test, and discloses a safety airbag test method and system. The method comprises the following steps: obtaining target pressure data; obtaining pressure output characteristics of a safety airbag test system; taking the target pressure at each moment in the target pressure data as the expected output pressure of a magneto-fluid pressure boosting device, and determining the driving current of the magnetostrictive device corresponding to the expected output pressure based on the pressure output characteristics; and outputting the driving current to the magnetostrictive device to drive the magnetostrictive device to generate mechanical displacement, and converting the mechanical displacement into a gas pulse pressure by the magneto-fluid pressure boosting device and outputting the gas pulse pressure to the safety airbag to test the safety airbag. The method can effectively reduce the test cost, improve the test safety, and improve the consistency of the test results.

Description

Technical Field

[0001] This application relates to the field of vehicle safety testing technology, and in particular to a method and system for testing airbags. Background Technology

[0002] Airbags are a core component of automotive passive safety, and their deployment test is a necessary step in verifying airbag performance. Currently, the industry mainly uses a real gunpowder gas generator for deployment testing, which involves igniting gunpowder to generate high-pressure gas that drives the airbag to deploy.

[0003] However, this method has the following problems: First, the gunpowder gas generator is for single use, and each test requires one generator, resulting in high testing costs; second, gunpowder explosions pose safety hazards such as explosions and fires, placing extremely high demands on the testing environment and personnel protection; third, the consistency and repeatability of test results are poor due to factors such as gunpowder batches and ambient temperature. Therefore, there is an urgent need to provide a new testing method to solve these problems.

[0004] The above content is only used to help understand the technical solution of this application and does not represent an admission that the above content is prior art. Summary of the Invention

[0005] The main objective of this application is to provide an airbag testing method and system that can effectively reduce testing costs, improve testing safety, and enhance the consistency of test results.

[0006] In a first aspect, this application provides an airbag testing method applied to an airbag testing system, the system comprising a processor, a magnetostrictive device electrically connected to the processor, and a magnetohydrodynamic pressurization device mechanically coupled to the magnetostrictive device; the method is executed by the processor, and the method includes: Acquire target pressure data, which characterizes the change in the required inflation pressure of the airbag to be tested over time; The pressure output characteristics of the airbag testing system are obtained, and the pressure output characteristics characterize the mapping relationship between the driving current of the magnetostrictive device and the output pressure of the magnetohydrodynamic pressurization device. The target pressure at each moment in the target pressure data is taken as the desired output pressure of the magnetohydrodynamic booster device, and based on the pressure output characteristics, the driving current of the magnetostrictive device corresponding to the desired output pressure is determined; and The driving current is output to the magnetostrictive device to drive the magnetostrictive device to generate mechanical displacement, and the mechanical displacement is converted into gas pulse pressure and output to the airbag through the magnetohydrodynamic pressurization device to test the airbag.

[0007] In this embodiment, the target pressure data characterizes the time-varying pattern of the required inflation pressure of the airbag under test. The pressure output characteristics of the airbag testing system reflect the mapping relationship between the driving current of the magnetostrictive device and the output pressure of the magnetohydrodynamic pressurization device. Therefore, by using the target pressure at each moment in the target pressure data as the desired output pressure of the magnetohydrodynamic pressurization device, the driving current of the magnetostrictive device corresponding to the desired output pressure can be accurately determined based on the pressure output characteristics. This driving current is then output to the magnetostrictive device, driving it to generate mechanical displacement. The magnetohydrodynamic pressurization device converts this mechanical displacement into gas pulse pressure, which is then output to the airbag under test. This accurately converts the desired output pressure into the actual inflation power of the airbag, achieving performance testing of the airbag. Because a fully electric drive method is used, there is no need to consume a gunpowder-based gas generator, thus significantly reducing testing costs. Simultaneously, it avoids safety hazards such as explosions and fires caused by gunpowder detonation, improving testing safety. Furthermore, the output pressure curve can be flexibly adjusted by precisely controlling the driving current, unaffected by gunpowder batches or ambient temperature, ensuring the consistency and repeatability of test results as much as possible. In summary, this application can effectively reduce testing costs, improve testing security, and enhance the consistency of test results.

[0008] In some embodiments, acquiring the target pressure data includes: Obtain standard pressure data at standard temperature; Get the current ambient temperature; Determine the temperature compensation parameters corresponding to the current ambient temperature; and Based on the temperature compensation parameters, the pressure at each moment in the standard pressure data is corrected to obtain target pressure data that is adapted to the current ambient temperature.

[0009] In this embodiment, standard pressure data at a standard temperature and the current ambient temperature are acquired, and corresponding temperature compensation parameters are determined. The standard pressure data is then corrected based on these temperature compensation parameters to obtain target pressure data adapted to the current ambient temperature. Because a temperature compensation mechanism is introduced, target pressure data matching the actual temperature conditions can be output under different ambient temperatures, expanding the applicability of the testing method and improving testing accuracy across the entire temperature range.

[0010] In some embodiments, determining the temperature compensation parameter corresponding to the current ambient temperature includes: Obtain the gas compressibility factor corresponding to the current ambient temperature and the gas compressibility factor corresponding to the standard temperature; and The temperature compensation parameter is determined based on the ratio of the current ambient temperature to the standard temperature, the ratio of the gas compressibility factor corresponding to the current ambient temperature to the gas compressibility factor corresponding to the standard temperature, and the gas generation rate temperature coefficient of the target gas generator.

[0011] In this embodiment, the temperature compensation parameters are determined by obtaining the gas compressibility factors corresponding to the current ambient temperature and the standard temperature, and combining the ratio of the current ambient temperature to the standard temperature, the ratio of the gas compressibility factors, and the temperature coefficient of the gas generation rate. Because the direct influence of temperature on gas pressure, the real gas effect, and the temperature dependence of the gas generation rate of the target gas generator are comprehensively considered, the temperature compensation is more accurate, further improving the accuracy of simulating the pressure output of the target gas generator under different temperature conditions.

[0012] In some embodiments, acquiring the target pressure data includes: Acquire standard pressure data of the target gas generator in its initial state; Determine the aging correction parameters corresponding to the aging degree of the target gas generator; and The pressure at each moment in the standard pressure data is corrected based on the aging correction parameters to obtain the target pressure data of the target gas generator under aging conditions.

[0013] In this embodiment, standard pressure data of the target gas generator in its initial state is obtained, and an aging correction parameter corresponding to the degree of aging is determined. The standard pressure data is then corrected based on this aging correction parameter to obtain the target pressure data under aging conditions. The introduction of aging simulation functionality allows the testing system to simulate the performance degradation of the target gas generator after a certain number of uses, thereby expanding the testing dimensions and improving the comprehensiveness of the test.

[0014] In some embodiments, after outputting the drive current to the magnetostrictive device, the method further includes: Collect the actual pressure output from the magnetohydrodynamic pressurization device to the airbag at the current moment; Determine the pressure deviation between the actual pressure and the target pressure corresponding to the current moment; and The current correction amount is determined based on the pressure deviation, and the current correction amount is added to the drive current at the next moment.

[0015] In this embodiment, after outputting the driving current to the magnetostrictive device, the actual pressure at the current moment is collected, the pressure deviation between the current pressure and the target pressure is calculated, and a current correction amount is determined based on the pressure deviation and added to the driving current at the next moment. Because a closed-loop feedback correction mechanism is introduced, output deviations caused by system nonlinearity, external disturbances, and other factors can be corrected in real time, making the actual output pressure closer to the target pressure, further improving the tracking accuracy of the target pressure data and the accuracy of the test results.

[0016] In some embodiments, determining the current correction amount based on the pressure deviation includes: Obtain the pressure deviation from the previous moment and the cumulative pressure deviation from the current moment; and The current correction amount is determined based on the pressure deviation at the current moment, the pressure deviation at the previous moment, and the cumulative value.

[0017] In this embodiment, the current correction amount is determined based on the pressure deviation at the current moment, the pressure deviation at the previous moment, and the cumulative value of the pressure deviation. By comprehensively considering the current deviation, historical deviation accumulation, and deviation change trend, the feedback correction is made smoother and faster, further improving the dynamic response performance of the system and the stability of pressure control.

[0018] In some embodiments, obtaining the pressure output characteristics of the airbag testing system includes: Multiple static currents of different amplitudes are input into the magnetostrictive device, the corresponding steady-state pressures are measured, and a static mapping relationship between the static currents and the steady-state pressures is established. A dynamic current that varies with time is input into the magnetostrictive device, the corresponding dynamic pressure is measured, and a dynamic mapping relationship between the dynamic current and the dynamic pressure is established; and Based on the static mapping relationship and the dynamic mapping relationship, the pressure output characteristics of the airbag testing system are constructed.

[0019] In this embodiment, a static mapping relationship is established by measuring steady-state pressure through inputting static currents of different amplitudes to the magnetostrictive device, and a dynamic mapping relationship is established by inputting dynamic currents to measure dynamic pressure. Based on both, pressure output characteristics are constructed. Because both static nonlinearity and dynamic response characteristics are comprehensively considered, the established pressure output characteristics more fully reflect the actual working characteristics of the magnetostrictive device and the magnetohydrodynamic pressurization device, providing a more accurate basis for subsequently determining the driving current, thereby improving the accuracy of target pressure data reproduction.

[0020] Secondly, to achieve the above objectives, this application provides an airbag testing system, the system comprising a processor, a magnetostrictive device, and a magnetohydrodynamic pressurization device; The processor is electrically connected to the magnetostrictive device, and the power output end of the magnetostrictive device is drive-connected to the power input end of the magnetohydrodynamic booster device. The processor is configured to acquire target pressure data, which characterizes the change in the required inflation pressure of the airbag under test over time; acquire the pressure output characteristics of the airbag testing system, which characterizes the mapping relationship between the driving current of the magnetostrictive device and the output pressure of the magnetohydrodynamic pressurization device; use the target pressure at each moment in the target pressure data as the desired output pressure of the magnetohydrodynamic pressurization device, and determine the driving current of the magnetostrictive device corresponding to the desired output pressure based on the pressure output characteristics; and output the driving current to the magnetostrictive device. The magnetostrictive device is used to receive and respond to the driving current to generate mechanical displacement, and to output the mechanical displacement to the magnetohydrodynamic pressurization device through the power output terminal; and The magnetohydrodynamic pressurization device is used to receive the mechanical displacement through the power input terminal, convert the mechanical displacement into gas pulse pressure and output it to the airbag to test the airbag.

[0021] In this embodiment, the airbag testing system includes a processor, a magnetostrictive device, and a magnetohydrodynamic pressurization device. The processor acquires target pressure data and pressure output characteristics, determines the driving current, and outputs it to the magnetostrictive device. The magnetostrictive device responds to the driving current to generate mechanical displacement. The magnetohydrodynamic pressurization device converts the mechanical displacement into gas pulse pressure and outputs it to the airbag. Through the coordinated operation of these components, a fully electrically driven airbag test is achieved. Since there is no need to consume a propellant gas generator, the testing cost is significantly reduced; at the same time, the safety risks associated with propellant explosions are avoided, improving testing safety; furthermore, the output pressure curve can be flexibly adjusted by precisely controlling the driving current, ensuring the consistency and repeatability of the test results.

[0022] In some embodiments, the magnetostrictive device includes an excitation coil and a super magnetostrictive rod; The excitation coil is sleeved on the outer periphery of the supermagnetostrictive rod, used to generate an excitation magnetic field in response to the driving current; and One end of the super magnetostrictive rod forms the power output end of the magnetostrictive device, which abuts against the power input end of the magnetohydrodynamic pressurization device. It is used to deform under the action of the excitation magnetic field to generate the mechanical displacement, and output the mechanical displacement to the power input end of the magnetohydrodynamic pressurization device through the power output end.

[0023] In this embodiment, the magnetostrictive device includes an excitation coil and a supermagnetic-strictive rod. The excitation coil generates an excitation magnetic field in response to a driving current. Under the influence of this magnetic field, the supermagnetic-strictive rod deforms, producing mechanical displacement, which is output to a magnetohydrodynamic pressurization device through a power output end formed at one end. Because the supermagnetic-strictive material has the characteristics of fast response speed and large output force, it can achieve microsecond-level mechanical displacement output, thereby meeting the requirements of simulating the transient impact response of a target gas generator and improving the timeliness and accuracy of target pressure data reproduction.

[0024] In some embodiments, the magnetohydrodynamic booster includes a booster cylinder, a booster piston, and a magnetohydrodynamic sealing component; The booster cylinder is provided with a gas outlet, which is used to connect to the airbag. The booster piston is slidably disposed within the booster cylinder, with one end serving as the power input terminal of the magnetohydrodynamic booster device and drivingly connected to the power output terminal of the magnetostrictive device. Driven by the mechanical displacement, it reciprocates within the booster cylinder to compress the gas within the cylinder, and then outputs the compressed gas through the gas outlet to the airbag. The magnetohydrodynamic sealing component is disposed between the booster piston and the inner wall of the booster cylinder, and is used to form a sealing barrier when the booster piston moves to prevent gas leakage from the booster cylinder.

[0025] In this embodiment, the magnetohydrodynamic (MHD) pressurization device includes a pressurization cylinder, a pressurization piston, and a MHD sealing component. Driven by mechanical displacement, the pressurization piston reciprocates within the pressurization cylinder, compressing gas and outputting it to the airbag through a gas outlet. The MHD sealing component forms a sealing barrier during piston movement, preventing gas leakage. Due to the use of MHD sealing technology, good sealing performance is maintained even during the high-speed reciprocating motion of the piston, avoiding pressure loss caused by gas leakage and ensuring the stability and accuracy of the output pressure.

[0026] Thirdly, to achieve the above objectives, this application also proposes a storage medium, which is a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the airbag testing method described above.

[0027] Fourthly, to achieve the above objectives, this application also proposes a computer program product, which includes a computer program that, when executed by a processor, implements the steps of the airbag testing method described above.

[0028] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application, it can be implemented according to the contents of the specification. In order to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0029] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A flowchart illustrating an airbag testing method provided in some embodiments of this application; Figure 2 One of the embodiments provided in this application Figure 1 A detailed step diagram of step S10; Figure 3 Another embodiment provided for some embodiments of this application Figure 1 A detailed step diagram of step S10; Figure 4 One of the embodiments provided in this application Figure 1 A detailed step diagram of step S20; Figure 5 One of the embodiments provided in this application Figure 1 A detailed step diagram of step S30; Figure 6 One of the embodiments provided in this application Figure 1 A schematic diagram of the subsequent new steps in step S40; Figure 7 This application provides a schematic diagram of the algorithm flow for an airbag testing method in some embodiments; Figure 8 A schematic diagram of the module structure of an airbag testing system provided in some embodiments of this application; Figure 9 This is a schematic diagram of the layered architecture of an airbag testing system provided in some embodiments of this application.

[0030] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0031] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0033] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0034] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0035] In the description of the embodiments in this application, the character " / " generally indicates that the preceding and following objects are in an "or" relationship. The term "multiple" refers to two or more (including two).

[0036] In the description of the embodiments of this application, the technical terms "lateral", "front", "inner", "outer", "axial", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0037] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0038] Airbags are a core component of automotive passive safety, and their deployment test is a necessary step in verifying airbag performance. Currently, the industry mainly uses two testing methods: one is the actual gunpowder gas generator deployment, which uses gunpowder to generate high-pressure gas to drive the airbag deployment; the other is high-pressure gas cylinder pulse inflation, which uses a high-pressure gas cylinder instead of gunpowder and releases gas rapidly through a solenoid valve.

[0039] The detonation of a real gunpowder gas generator has the following drawbacks: the gunpowder gas generator is for single use, and each test requires the consumption of one generator, resulting in high testing costs; gunpowder explosions pose safety hazards such as explosions and fires, requiring extremely high standards for the testing environment and personnel protection; the consistency and repeatability of test results are poor due to factors such as the batch of gunpowder and ambient temperature; in addition, it generates waste gas and residue, causing environmental pollution.

[0040] High-pressure gas cylinder pulse filling has the following drawbacks: the mechanical response time of the solenoid valve is usually in the millisecond range, which cannot simulate the microsecond-level transient impact of gunpowder explosion; it cannot reproduce the nonlinear filling characteristics of the gunpowder gas generator; and it cannot maintain consistency across the entire temperature range from -40 degrees Celsius to 120 degrees Celsius.

[0041] The airbag testing method provided in this application uses target pressure data to characterize the change in the required inflation pressure of the airbag under test over time. The pressure output characteristics of the airbag testing system reflect the mapping relationship between the driving current of the magnetostrictive device and the output pressure of the magnetohydrodynamic pressurization device. Therefore, by using the target pressure at each moment in the target pressure data as the desired output pressure of the magnetohydrodynamic pressurization device, the driving current of the magnetostrictive device corresponding to the desired output pressure can be accurately determined based on the pressure output characteristics. This driving current is then output to the magnetostrictive device, driving it to generate mechanical displacement. The magnetohydrodynamic pressurization device converts this mechanical displacement into gas pulse pressure, which is then output to the airbag under test. This accurately converts the desired output pressure into the actual inflation power of the airbag, achieving performance testing of the airbag. Because it uses a fully electric drive method, there is no need to consume a gunpowder-based gas generator, thus significantly reducing testing costs. Simultaneously, it avoids the safety hazards of explosions and fires caused by gunpowder detonation, improving testing safety. Furthermore, the output pressure curve can be flexibly adjusted by precisely controlling the driving current, unaffected by gunpowder batches or ambient temperature, ensuring the consistency and repeatability of test results as much as possible. Compared to the pulse charging method for high-pressure gas cylinders, this application offers a faster response speed, capable of simulating microsecond-level transient impacts and replicating the nonlinear charging characteristics of propellant gas generators. Furthermore, it maintains consistency across the entire temperature range through a temperature compensation mechanism. In summary, this application effectively reduces testing costs, improves testing safety, and enhances the consistency of test results.

[0042] The airbag testing scheme disclosed in this application can be applied to various scenarios. For example, during the research and development stage of automotive airbags, it can be used to conduct equivalent simulation tests on different models of gunpowder gas generators to verify the airbag deployment performance under different operating conditions, shortening the research and development cycle and reducing testing costs. In the production quality inspection stage, it can be used to conduct batch sampling inspections of airbag assemblies before they leave the factory to ensure product consistency and reliability. In the after-sales maintenance field, it can be used to simulate the airbag deployment state after the gas generator has aged or failed, assisting in the evaluation of the safety performance of used vehicles. In addition, it can be extended to other occasions that require the rapid generation of controllable pulse gas, such as aviation rescue airbags. This application does not limit these applications.

[0043] Please refer to Figure 1 , Figure 1 This is a flowchart illustrating an airbag testing method provided in some embodiments of this application. The method is applied to an airbag testing system, which includes a processor, a magnetostrictive device electrically connected to the processor, and a magnetohydrodynamic pressurization device mechanically coupled to the magnetostrictive device. The method is executed by the processor and includes the following steps: S10, acquire target pressure data, which characterizes the change in the required inflation pressure of the airbag under test over time; S20, Obtain the pressure output characteristics of the airbag testing system. The pressure output characteristics characterize the mapping relationship between the drive current of the magnetostrictive device and the output pressure of the magnetohydrodynamic pressurization device. S30, the target pressure at each moment in the target pressure data is taken as the desired output pressure of the magnetohydrodynamic booster, and the driving current of the magnetostrictive device corresponding to the desired output pressure is determined based on the pressure output characteristics; and S40 outputs a driving current to the magnetostrictive device to drive the magnetostrictive device to generate mechanical displacement, and converts the mechanical displacement into gas pulse pressure through the magnetohydrodynamic pressurization device and outputs it to the airbag to test the airbag.

[0044] Target pressure data characterizes the change in required inflation pressure of the airbag under test over time, typically presented as a pressure-time curve. This data serves as a target reference for the simulation output of this scheme.

[0045] For example, the target pressure data is the pressure data of the target gas generator, that is, the set of values ​​showing the change in output pressure of the target gas generator over time after startup. The target gas generator serves as the reference object to be simulated in this solution; it can be a real gunpowder-type gas generator or other types of gas pressure sources. This solution simulates its pressure output characteristics using an electric drive to replace the generator in airbag testing.

[0046] A magnetostrictive device is an actuator that converts electrical energy into mechanical energy using the magnetostrictive effect. In this scheme, the device receives a driving current and generates mechanical displacement with a micrometer-level or microsecond-level response, providing the driving force for the generation of gas pulses.

[0047] A magnetohydrodynamic (MHD) booster device refers to a booster mechanism mechanically coupled to a magnetostrictive device. This device receives the mechanical displacement output from the magnetostrictive device, compresses gas via an internal piston, converts the mechanical displacement into a high-pressure gas pulse, and outputs it to the airbag.

[0048] Pressure output characteristics refer to the mapping relationship between the output pressure of the magnetohydrodynamic booster and the input drive current of the magnetostrictive device. This is used to determine the drive current required to achieve the target pressure.

[0049] The desired output pressure refers to the output pressure that the magnetohydrodynamic booster device needs to achieve at a certain moment. In this scheme, the desired output pressure is taken from the pressure value at the corresponding moment in the target pressure data, serving as the direct basis for determining the drive current of the magnetostrictive device.

[0050] The driving current refers to the current signal input to the excitation coil of the magnetostrictive device. By adjusting this current, the amplitude of the mechanical displacement generated by the magnetostrictive device can be controlled, thereby achieving precise control of the output pressure of the magnetohydrodynamic pressurization device.

[0051] Mechanical displacement refers to the deformation displacement that occurs in a magnetostrictive device under the action of a driving current. This displacement serves as the input to a magnetohydrodynamic pressurization device, driving the internal piston to compress the gas.

[0052] Gas pulse pressure refers to the instantaneous high-pressure gas output from the magnetohydrodynamic pressurization device to the airbag, used to simulate the gas impact effect when the target gas generator detonates.

[0053] For example, target pressure data can be read from a preset database or generated through user-defined input, thereby improving the flexibility and applicability of target pressure data acquisition.

[0054] For example, the mapping relationship between the driving current of the magnetostrictive device and the output pressure of the magnetohydrodynamic booster device can be obtained through pre-conducted calibration experiments and stored in the form of tables, formulas, or models. This provides an accurate data basis for subsequent determination of the driving current, ensuring the accuracy of the pressure output.

[0055] Step S30 describes the core computational logic for achieving precise pressure control in the system. The processor first extracts the target pressure value at a specific moment from the target pressure data and directly sets it as the expected output pressure that the magnetohydrodynamic booster should achieve at that moment. Then, it calls upon the pre-acquired pressure output characteristics—the mapping relationship between drive current and output pressure—and uses this expected output pressure as a query condition to deduce and calculate the drive current value currently required by the magnetostrictive device. Through this calculation process, the system can transform the abstract pressure target into specific hardware control commands, thereby ensuring that the magnetohydrodynamic booster can output gas pulse pressure that conforms to the target pattern in real time and accurately.

[0056] For example, the drive current value corresponding to the desired output pressure of the magnetohydrodynamic booster can be determined based on the pressure output characteristics through methods such as table lookup, interpolation, or model calculation. This allows for the rapid and accurate acquisition of the required drive current, meeting the requirements of real-time control.

[0057] In this embodiment, the target pressure data characterizes the time-varying pattern of the required inflation pressure of the airbag under test. The pressure output characteristics of the airbag testing system reflect the mapping relationship between the driving current of the magnetostrictive device and the output pressure of the magnetohydrodynamic pressurization device. Therefore, by using the target pressure at each moment in the target pressure data as the desired output pressure of the magnetohydrodynamic pressurization device, the driving current of the magnetostrictive device corresponding to the desired output pressure can be accurately determined based on the pressure output characteristics. This driving current is then output to the magnetostrictive device, driving it to generate mechanical displacement. The magnetohydrodynamic pressurization device converts this mechanical displacement into gas pulse pressure, which is then output to the airbag under test. This accurately converts the desired output pressure into the actual inflation power of the airbag, achieving performance testing of the airbag. Because a fully electric drive method is used, there is no need to consume a gunpowder-based gas generator, thus significantly reducing testing costs. Simultaneously, it avoids safety hazards such as explosions and fires caused by gunpowder detonation, improving testing safety. Furthermore, the output pressure curve can be flexibly adjusted by precisely controlling the driving current, unaffected by gunpowder batches or ambient temperature, ensuring the consistency and repeatability of test results as much as possible. In summary, this application can effectively reduce testing costs, improve testing security, and enhance the consistency of test results.

[0058] Please refer to Figure 2 In some embodiments, S10 acquires target pressure data of the target gas generator, including: S101a, Obtain standard pressure data at standard temperature; S102a, Obtain the current ambient temperature; S103a, determine the temperature compensation parameters corresponding to the current ambient temperature; and S104a corrects the pressure at each moment in the standard pressure data based on temperature compensation parameters to obtain target pressure data that is adapted to the current ambient temperature.

[0059] The standard temperature refers to the ambient temperature at which the standard pressure data is acquired. For example, the standard temperature is the ambient temperature used when the target gas generator being simulated was calibrated at the factory, which is usually room temperature, such as 23°C. The standard pressure data measured at this temperature serves as the reference for subsequent temperature compensation.

[0060] Standard pressure data refers to the variation of the required inflation pressure of the airbag under test over time at a standard temperature. For example, standard pressure data is the pressure change over time measured by the target gas generator under standard temperature conditions, usually presented as a pressure-time curve. This data reflects the output characteristics of the gas generator under reference operating conditions.

[0061] The current ambient temperature refers to the actual ambient temperature in which the airbag testing system operates during testing. This temperature may differ from the standard temperature, requiring temperature compensation to correct the standard pressure data to ensure that the test results match actual operating conditions.

[0062] Temperature compensation parameters refer to correction factors or functions used to adjust standard pressure data to adapt to the current ambient temperature. These parameters are calculated based on the difference between the current ambient temperature and the standard temperature, and are used to adjust the pressure values ​​at various times so that the corrected target pressure data can be adapted to the current ambient temperature, thereby reflecting the actual output characteristics of the target gas generator at the current temperature.

[0063] Optionally, standard pressure data of the target gas generator at a standard temperature can be read from a preset database. For example, the system first receives a command triggered by the user via a host computer to select the model of the target gas generator to be tested. Subsequently, the system automatically retrieves the core reference parameters associated with that model from the preset database, including: the standard pressure-time curve, i.e. Its data format is time series. And sampling time interval The sampling rate is consistent with the measured data of the target gas generator. Simultaneously, the volume parameters of this model are read. and reference temperature For example, the reference temperature is 23°C.

[0064] Optionally, after acquiring the standard pressure data, interpolation can be performed on the standard pressure data to obtain a high-resolution pressure-time curve. For example, using cubic spline interpolation makes the sampling interval... To match the processor's control cycle.

[0065] Optionally, the current ambient temperature can be acquired using a temperature sensor. For example, the sampling frequency of the temperature sensor is greater than or equal to 100Hz.

[0066] Optionally, the temperature compensation parameters corresponding to the current ambient temperature are determined, including: obtaining the gas compressibility factor corresponding to the current ambient temperature and the gas compressibility factor corresponding to the standard temperature; and determining the temperature compensation parameters based on the ratio of the current ambient temperature to the standard temperature, the ratio of the gas compressibility factor corresponding to the current ambient temperature to the gas compressibility factor corresponding to the standard temperature, and the gas generation rate temperature coefficient of the target gas generator.

[0067] The gas compressibility factor is a dimensionless parameter used to correct deviations between the equation of state for real gases and that for ideal gases. Because the intermolecular forces and volume of gas molecules are not negligible under high temperature and pressure, the gas compressibility factor is not equal to 1. Its specific value is related to the ambient temperature and can be obtained through a pre-established lookup table method in engineering implementation.

[0068] The gas generation rate temperature coefficient is a physical coefficient characterizing the change in the internal gas generation rate of a target gas generator under different ambient temperatures. This coefficient is highly dependent on the specific model and design of the gas generator and can be obtained through mathematical fitting based on measured data.

[0069] For example, the temperature compensation parameters can be determined using the following formula: Formula (1):

[0070] in, For temperature compensation parameters, The current ambient temperature. Standard temperature Based on Gay-Lussac's law, the direct effect of temperature on gas pressure is characterized. It is the gas compressibility factor. This is the temperature coefficient of the gas generation rate.

[0071] For example, the pressure at each moment in the standard pressure data can be corrected using the following formula: Formula (2):

[0072] in, To adjust the target pressure to match the current ambient temperature, For temperature compensation parameters, The target pressure before the correction.

[0073] In this embodiment, the temperature compensation parameters are determined by obtaining the gas compressibility factors corresponding to the current ambient temperature and the standard temperature, and combining the ratio of the current ambient temperature to the standard temperature, the ratio of the gas compressibility factors, and the temperature coefficient of the gas generation rate. Because the direct influence of temperature on gas pressure, the real gas effect, and the temperature dependence of the gas generation rate of the target gas generator are comprehensively considered, the temperature compensation is more accurate, further improving the accuracy of simulating the pressure output of the target gas generator under different temperature conditions.

[0074] In this embodiment, standard pressure data at a standard temperature and the current ambient temperature are acquired, and corresponding temperature compensation parameters are determined. The standard pressure data is then corrected based on these temperature compensation parameters to obtain target pressure data adapted to the current ambient temperature. Because a temperature compensation mechanism is introduced, target pressure data matching the actual temperature conditions can be output under different ambient temperatures, expanding the applicability of the testing method and improving testing accuracy across the entire temperature range.

[0075] Please refer to Figure 3 In some embodiments, S10 acquires target pressure data of the target gas generator, including: S101b, acquire standard pressure data of the target gas generator in its initial state; S102b, determine the aging correction parameters corresponding to the aging degree of the target gas generator; and S103b corrects the pressure at each moment in the standard pressure data based on the aging correction parameters to obtain the target pressure data of the target gas generator under aging conditions.

[0076] The initial state refers to the original state of the target gas generator when it is brand new, unused, or has not experienced performance degradation. The standard pressure data measured in this state serves as the benchmark for subsequent aging simulations. The aging state refers to the state of the target gas generator after a certain number of uses, where its output characteristics have degraded or changed relative to the initial state. By correcting the standard pressure data with aging correction parameters, the target pressure data in this state can be obtained.

[0077] Standard pressure data refers to the pressure change over time measured by the target gas generator in its initial state, presented as a pressure-time curve. This data reflects the output characteristics of the gas generator in its new state.

[0078] Aging correction parameters refer to correction factors used to correct standard pressure data under initial conditions in order to simulate the output characteristics of a target gas generator at a specific degree of aging.

[0079] For example, the standard pressure data of the target gas generator in its initial state can be read from a preset database, or the data can be obtained through user input.

[0080] For example, the corresponding aging correction parameter can be automatically matched from the preset aging parameter model according to the aging degree specified by the user, or the user can directly input the parameter.

[0081] Optionally, the aging correction parameter includes at least one of the following: The peak attenuation coefficient characterizes the degree of energy decay of a target gas generator under aging conditions. Taking a gunpowder-type gas generator as an example, the peak attenuation coefficient quantifies the extent to which the combustion energy of the gunpowder declines with equipment aging. For example, the value of the peak attenuation coefficient ranges from 0.7 to 1.0.

[0082] The time scale factor is used to characterize the degree of change in the pressure rise rate of the target gas generator under aging conditions. For example, when the time scale factor is greater than 1, a pressure rise delay phenomenon is simulated; when the time scale factor is less than 1, a pressure rise rate increase phenomenon is simulated.

[0083] Bias pressure is used to characterize the deviation of the reference pressure of a target gas generator under aging conditions. For example, it can be caused by slow leakage due to deterioration of the equipment's sealing performance, or by residual prepressure changes within the system.

[0084] For example, the pressure at each moment in the standard pressure data can be corrected using the following formula: Formula (3):

[0085] in, This refers to the target pressure data of the target gas generator under aging conditions. The standard pressure data for the target gas generator in its initial state. The peak attenuation coefficient is... For time scale coefficients, This is the bias pressure.

[0086] In this embodiment, the aging correction parameters include at least one of a peak decay coefficient, a time scale coefficient, and a bias pressure. The peak decay coefficient characterizes the energy decay of the target gas generator under aging conditions, the time scale coefficient characterizes the change in the pressure rise rate of the target gas generator under aging conditions, and the bias pressure characterizes the offset of the target gas generator from the reference pressure under aging conditions. By introducing these parameters, the performance of the target gas generator at different aging stages can be flexibly simulated from multiple dimensions, making the aging simulation closer to real-world conditions and further improving the realism and effectiveness of the test.

[0087] In this embodiment, standard pressure data of the target gas generator in its initial state is obtained, and an aging correction parameter corresponding to the degree of aging is determined. The standard pressure data is then corrected based on this aging correction parameter to obtain the target pressure data under aging conditions. The introduction of aging simulation functionality allows the testing system to simulate the performance degradation of the target gas generator after a certain number of uses, thereby expanding the testing dimensions and improving the comprehensiveness of the test.

[0088] Please refer to Figure 4 In some embodiments, S20 acquires the pressure output characteristics of the airbag testing system, including: S201, input multiple static currents of different amplitudes into the magnetostrictive device, measure the corresponding steady-state pressure, and establish a static mapping relationship between static current and steady-state pressure; S202, Input a time-varying dynamic current into the magnetostrictive device, measure the corresponding dynamic pressure, and establish a dynamic mapping relationship between the dynamic current and the dynamic pressure; and S203, based on static and dynamic mapping relationships, constructs the pressure output characteristics of the airbag testing system.

[0089] Among them, the static current is the constant current input applied to the magnetostrictive device under steady-state conditions, which is mainly used to excite the steady-state output characteristics of the device.

[0090] Steady-state pressure is the stable gas pressure value output by the magnetohydrodynamic pressurization device to the airbag when the system reaches force equilibrium under static conditions.

[0091] A static mapping relationship is a mathematical model or data table that describes the correspondence between input current and output pressure of a device under static conditions.

[0092] For example, when the system is in a static state, a series of step currents of different amplitudes are applied to the magnetostrictive device. Measure the corresponding pressure after the steady state. Thus, a static mapping relationship is established. .

[0093] Among them, dynamic current is a current signal that changes continuously with time, such as a sinusoidal sweep signal of a specific frequency, which is used to fully stimulate the dynamic response characteristics of the system.

[0094] Dynamic pressure is the pressure fluctuation that occurs at the output of a system when faced with a non-constant current input, and it varies with time.

[0095] The dynamic mapping relationship is a mathematical model that characterizes the transmission law between the rate of change of input current and the output pressure response under dynamic excitation, such as the dynamic transfer function. .

[0096] For example, under dynamic conditions, sinusoidal swept-frequency current signals of different frequencies are input to the magnetostrictive device. By analyzing the relationship between the input current waveform and the output pressure waveform, the dynamic transfer function of the system is extracted. To characterize the dynamic inertia, delay, and frequency response of the device.

[0097] Based on the static mapping relationship obtained in the above steps and dynamic mapping relationship Construct the following Hammerstein model: Formula (4):

[0098] Using this model, the required inverse model formula can be further solved, namely, the pressure output characteristics of the airbag testing system: Formula (5):

[0099] After obtaining the inverse model formula, for the target pressure at each time point in the target pressure data... The required drive current can be calculated using this inverse model formula, as shown below: Formula (6):

[0100] in, For a moment The calculated feedforward drive current, For a moment Expected output target pressure It is the inverse model operator, that is, the inverse model operation represented by the formula (5) above.

[0101] It is understandable that there is a complex nonlinear relationship between the driving current of the magnetostrictive device and the output voltage of the magnetohydrodynamic booster, including phenomena such as hysteresis, saturation, and creep. To achieve accurate reproduction, the Preisach hysteresis model is adopted, with the following formula: Formula (7):

[0102] in, Let be the output voltage of the magnetohydrodynamic booster at time t. Let t be the driving current applied to the magnetostrictive device. , The switching threshold for the hysteresis operator. It is a hysteresis operator. For Preisach density function.

[0103] Since the density function and hysteresis operator in the Preisach hysteresis model are difficult to derive directly, this application provides a corresponding engineering solution. This solution transforms the complex microscopic hysteresis model into a macroscopically controllable engineering model through experimental identification. Specifically, it consists of two steps: establishing a static mapping relationship in step S201 to describe the static nonlinear characteristics of the device; and establishing the dynamic transfer function of the device in step S202 to describe its dynamic frequency characteristics. Based on this, step S203 combines the static mapping relationship and the dynamic transfer function in series to construct the Hammerstein model. This model transforms the complex Preisach integral model into a macroscopically controllable series form of static nonlinear elements and dynamic linear elements, providing an engineeringly feasible foundation for subsequent inverse model calculations in feedforward control.

[0104] In this embodiment, a static mapping relationship is established by measuring steady-state pressure through inputting static currents of different amplitudes to the magnetostrictive device, and a dynamic mapping relationship is established by inputting dynamic currents to measure dynamic pressure. Based on both, pressure output characteristics are constructed. Because both static nonlinearity and dynamic response characteristics are comprehensively considered, the established pressure output characteristics more fully reflect the actual working characteristics of the magnetostrictive device and the magnetohydrodynamic pressurization device, providing a more accurate basis for subsequently determining the driving current, thereby improving the accuracy of target pressure data reproduction.

[0105] Please refer to Figure 5 In some embodiments, S30 uses the target pressure at each moment in the target pressure data as the desired output pressure of the magnetohydrodynamic booster device, and determines the drive current of the magnetostrictive device corresponding to the desired output pressure based on the pressure output characteristics, including: S301, Obtain the current-pressure comparison table, which is generated based on the pressure output characteristics of the airbag testing system; S302, take the target pressure at each moment in the target pressure data as the expected output pressure of the magnetohydrodynamic booster, and look up the driving current corresponding to the expected output pressure from the current-pressure lookup table.

[0106] The current-pressure lookup table is a pre-generated lookup table based on the pressure output characteristics of the airbag testing system. This table establishes the correspondence between the output pressure value of the magnetohydrodynamic pressurization device and the required drive current value of the magnetostrictive device, stored as discrete data points for quick lookup during real-time control. When the desired output pressure falls between two discrete data points in the table, the corresponding drive current can be calculated using methods such as linear interpolation.

[0107] For example, during the system startup or calibration phase, based on the Hammerstein model constructed in step S20, a series of discrete output pressure values ​​and drive current values ​​are calculated through inverse modeling, and these are pre-stored as a current-pressure lookup table. This lookup table can be stored in the controller's memory to support high-speed lookup. During real-time control, the controller reads the target pressure values ​​at each moment in the target pressure data, on a per-control-cycle basis. For each target pressure value, the controller directly looks up the current-pressure lookup table. If the target pressure value matches a discrete data point in the table, the corresponding drive current value is read directly; otherwise, the corresponding drive current value is calculated using linear interpolation or other methods.

[0108] In this embodiment, a current-pressure lookup table is generated in advance based on the pressure output characteristics, and the drive current corresponding to the desired output pressure is directly looked up from the table during actual control. By using a lookup table instead of real-time calculation, the computational burden on the processor is significantly reduced, the time to determine the drive current is shortened, and the requirements for microsecond-level real-time control are met, thereby ensuring the real-time performance and continuity of the pressure output.

[0109] Please refer to Figure 6 In some embodiments, after outputting the drive current to the magnetostrictive device, the method further includes the following steps: S50, collects the actual pressure output from the magnetohydrodynamic pressurization device to the airbag at the current moment; S60, determine the pressure deviation between the actual pressure and the target pressure at the current moment; and S70 determines the current correction amount based on the pressure deviation and adds the current correction amount to the drive current at the next moment.

[0110] The actual pressure refers to the gas pressure value that the magnetohydrodynamic pressurization device actually outputs to the airbag at the current moment, which can be collected in real time by a high-frequency dynamic pressure sensor.

[0111] Pressure deviation refers to the difference between the actual pressure and the target pressure at a given moment. For example, pressure deviation is the target pressure minus the actual pressure. This deviation measures the degree of deviation between the system output and the expected output. For instance, the pressure deviation at a given moment can be calculated using the following formula: Formula (7):

[0112] in, The pressure deviation at the current moment, For the current moment's target pressure, This represents the actual pressure at the current moment.

[0113] The current correction is the adjustment value of the drive current calculated based on the pressure deviation. This correction is used to compensate for the feedforward drive current at the next moment, in order to reduce or eliminate the pressure deviation between the actual output and the target output.

[0114] In some embodiments, determining the current correction amount based on the pressure deviation includes: obtaining the pressure deviation at the previous moment and the cumulative value of the pressure deviation at the current moment; and determining the current correction amount based on the pressure deviation at the current moment, the pressure deviation at the previous moment, and the cumulative value.

[0115] The pressure deviation at the previous moment refers to the pressure deviation value calculated within one control cycle prior to the current moment. This value is used to reflect the trend of deviation change.

[0116] The cumulative pressure deviation at the current moment refers to the sum of the pressure deviations over all control cycles from the start of control to the current moment. This cumulative value is used to reflect the long-term cumulative effect of the deviation.

[0117] For example, the current correction can be determined using an incremental PID (Proportional-Integral-Derivative) algorithm. That is, the current correction is calculated using the following formula: Formula (8):

[0118] in, , , These are the proportional, integral, and derivative parameters of the PID algorithm, which can be tuned using the Ziegler-Nichols method or adaptively adjusted online. The pressure deviation at the current moment, This represents the pressure deviation from the previous moment. This represents the cumulative value of the pressure deviation at the current moment.

[0119] In this embodiment, the current correction amount is determined based on the pressure deviation at the current moment, the pressure deviation at the previous moment, and the cumulative value of the pressure deviation. By comprehensively considering the current deviation, historical deviation accumulation, and deviation change trend, the feedback correction is made smoother and faster, further improving the dynamic response performance of the system and the stability of pressure control.

[0120] Adding the current correction to the drive current at the next moment means adding the current correction to the feedforward drive current at the next moment to obtain the final drive current value output to the magnetostrictive device. This superposition correction achieves composite control combining feedforward and feedback. For example, the drive current output to the magnetostrictive device at the next moment is calculated using the following formula.

[0121] Formula (9):

[0122] in, This is the drive current output to the magnetostrictive device at the next moment, i.e., the final drive current after superposition and correction. This is the feedforward drive current for the next moment, i.e., the base drive current without the added current correction. This is the current correction amount.

[0123] Optionally, after adding the current correction to the drive current at the next moment, the drive current at the next moment also needs to be limited to prevent overcurrent damage to components. Here, limiting refers to limiting the final output drive current at the next moment. The maximum value is physically bounded to ensure it remains within a safe threshold range. When the calculated... When the current exceeds the system's maximum safe output current threshold, it will be forcibly cut off and set to [unclear]. It equals the maximum safe output current, thus avoiding excessive output current.

[0124] It is understood that this application achieves dynamic tracking of the target pressure curve by synchronously completing waveform generation, power amplification, and closed-loop feedback correction within each extremely short control cycle through iterative loops. For example, the magnetostrictive device includes a power drive unit and a magnetostrictive actuator; during the microsecond-level real-time output phase, the controller... The high-frequency period is used as the step size to sequentially read the set current sequence. The sequence is converted into analog voltage control signals by a high-speed digital-to-analog converter. , The power is amplified by the high-frequency PWM (Pulse-Width Modulation) power drive unit and finally converted into a large current. The magnetostrictive actuator is driven to output displacement. During this period, the power drive employs a closed-loop control strategy to ensure that the deviation between the actual output current and the set value is strictly controlled within 1%. After power amplification, the system enters the closed-loop feedback correction stage, calculating the current correction amount based on the real-time pressure deviation and adding it to the drive current at the next moment. After completing the above steps, the system enters the iterative and termination judgment stage: continuously repeating the waveform generation, amplification, and feedback correction process. This process continues until the target curve time series ends, i.e., at the current moment... ≥ At this point, the system stops iterating. Subsequently, the controller output returns to zero, and the system enters standby mode, thus completing the entire dynamic output process. The controller can be an FPGA (Field-Programmable Gate Array).

[0125] Optionally, after completing the aforementioned closed-loop feedback correction and iterative iteration, this application also includes data recording and post-processing steps. The system uploads key parameters such as the target pressure curve, actual output pressure curve, drive current data, and ambient temperature during the test to the host computer. Based on the received data, the host computer automatically generates a test report and calculates multiple evaluation indicators such as peak pressure error, time error, and integral flow error to quantitatively assess the degree of agreement between the test results and the target pressure curve. Furthermore, all test data is stored in a pre-set database, supporting playback and comparative analysis of historical test results. This facilitates users in tracing the test performance of different batches, providing data support for subsequent R&D improvements and quality control.

[0126] In this embodiment, after outputting the driving current to the magnetostrictive device, the actual pressure at the current moment is collected, the pressure deviation between the current pressure and the target pressure is calculated, and a current correction amount is determined based on the pressure deviation and added to the driving current at the next moment. Because a closed-loop feedback correction mechanism is introduced, output deviations caused by system nonlinearity, external disturbances, and other factors can be corrected in real time, making the actual output pressure closer to the target pressure, further improving the tracking accuracy of the target pressure data and the accuracy of the test results.

[0127] Please refer to Figure 7 , Figure 7 This is a schematic diagram of the algorithm flow for an airbag testing method provided in this application. The entire algorithm starts from the beginning node. First, the user inputs parameters such as generator model, temperature, and aging mode. Based on this, the processor extracts the standard pressure curve, reference temperature, and volume parameters of the corresponding model from the database. Then, it determines whether aging simulation is required. If the determination is "yes," the aging model is applied to attenuate and correct the standard pressure curve, generating the target pressure curve after aging; if the determination is "no," the standard pressure curve is directly used as the target pressure curve. Next, the processor performs temperature compensation: it reads the current actual temperature, calculates the temperature compensation coefficient, and corrects the target pressure curve to obtain the temperature-compensated pressure curve. Then, based on the pressure-current inverse model, the feedforward drive current corresponding to the target pressure at each moment in the compensated pressure curve is obtained through table lookup or numerical calculation.

[0128] Continue to refer to Figure 7After calculating the feedforward drive current at each moment, the processor initializes the time, timing index, and output current, and determines whether the current time has reached the set test end time. If the end time has not been reached, the processor executes a closed-loop control step. This closed-loop control step includes: sending the output current to the magnetostrictive device and synchronously reading the actual pressure output by the magnetohydrodynamic pressurization device; calculating the pressure deviation between the current actual pressure and the corresponding target pressure, and calculating the current correction amount using a proportional-integral-derivative algorithm; then adding the current correction amount to the feedforward current calculated in the next control cycle, limiting the obtained current, and using the limited current as the output current for the next control cycle. After completing a single loop, the time index increments, the processor returns and re-determines whether the end time has been reached, preparing for the next closed-loop control step. If it is determined that the current time has reached the set test end time, the current output is stopped, the test data is uploaded to the host computer, and finally a test report is generated, ending the entire algorithm process.

[0129] Please refer to Figure 8 , Figure 8 The present application provides a schematic diagram of the module structure of an airbag testing system 800, which includes a processor 801, a magnetostrictive device 802, and a magnetohydrodynamic pressurization device 803. The processor 801 is electrically connected to the magnetostrictive device 802, and the power output end of the magnetostrictive device 802 is drive-connected to the power input end of the magnetohydrodynamic booster device 803. The processor 801 is used to acquire target pressure data, which characterizes the change in the required inflation pressure of the airbag under test over time; acquire the pressure output characteristics of the airbag testing system 800, which characterizes the mapping relationship between the driving current of the magnetostrictive device 802 and the output pressure of the magnetohydrodynamic pressurization device 803; use the target pressure at each moment in the target pressure data as the expected output pressure of the magnetohydrodynamic pressurization device, and determine the driving current of the magnetostrictive device 802 corresponding to the expected output pressure based on the pressure output characteristics; and output the driving current to the magnetostrictive device 802. Magnetostrictive device 802 is used to receive and respond to driving current to generate mechanical displacement, and output mechanical displacement to magnetohydrodynamic pressurization device 803 through power output terminal; and The magnetohydrodynamic pressurization device 803 is used to receive mechanical displacement through the power input end, convert the mechanical displacement into gas pulse pressure and output it to the airbag for testing.

[0130] For example, the magnetostrictive device 802 includes a power drive unit and a magnetostrictive actuator. The power drive unit is electrically connected to both the processor 801 and the magnetostrictive actuator. The power drive unit receives a drive current from the processor 801, which is a weak current control signal. The power drive unit amplifies, limits, and conditions the waveform of this weak current control signal to output a high-power drive current that meets the operating requirements of the magnetostrictive actuator. The magnetostrictive actuator receives the drive current output by the power drive unit and, based on the magnetostrictive effect, generates a high-precision, high-speed response mechanical displacement as the current changes. This mechanical displacement is then synchronously transmitted to the power input of the magnetohydrodynamic booster device 803 via the power output terminal.

[0131] Optionally, the magnetostrictive device 802 includes an excitation coil and a super magnetostrictive rod. The excitation coil, sleeved on the outer periphery of the super magnetostrictive rod, generates an excitation magnetic field in response to a driving current. One end of the super magnetostrictive rod forms the power output end of the magnetostrictive device 802, abutting against the power input end of the magnetohydrodynamic pressurization device 803. It deforms under the action of the excitation magnetic field to generate mechanical displacement, and outputs this mechanical displacement to the power input end of the magnetohydrodynamic pressurization device 803 through the power output end.

[0132] For example, in addition to the excitation coil and the giant magnetostrictive rod, the magnetostrictive device 802 also includes a preload spring. This preload spring is coaxially mounted with the giant magnetostrictive rod, with one end abutting against the internal fixed base of the magnetostrictive device 802, and the other end pressing against the tail end of the giant magnetostrictive rod away from the power output end. The preload spring is used to continuously apply axial preload force to the giant magnetostrictive rod: firstly, to compact the internal grain gaps of the giant magnetostrictive rod, reducing the hysteresis effect and maintaining a stable correspondence between the rod's expansion and contraction displacement and the driving current; secondly, to continuously push the giant magnetostrictive rod forward, ensuring that its front power output end always closely contacts the power input end of the magnetohydrodynamic booster device 803, eliminating transmission gaps and avoiding pressure pulse response lag and waveform distortion.

[0133] For example, the magnetostrictive device 802 includes a power drive unit and a magnetostrictive actuator, wherein the magnetostrictive actuator includes an excitation coil, a super magnetostrictive rod, and a preload spring. One end of the power drive unit is electrically connected to the processor 801 to receive a weak current drive from the processor 801, and the other end is electrically connected to the excitation coil inside the magnetostrictive actuator to deliver a conditioned and amplified high-power current to the excitation coil. The excitation coil is coaxially sleeved on the outer periphery of the super magnetostrictive rod, and the preload spring is coaxially sleeved with the super magnetostrictive rod. One end of the spring abuts against the fixed base inside the actuator, and the other end presses against the tail of the super magnetostrictive rod away from the power output end. The power output end of the super magnetostrictive rod mechanically abuts against the power input end of the magnetohydrodynamic booster device 803.

[0134] During operation, the power drive unit amplifies the weak electrical signal and supplies it to the excitation coil. The excitation coil is energized to generate a magnetic field that drives the giant magnetostrictive rod to deform and output displacement. The preload spring continuously applies preload force to reduce hysteresis and eliminate transmission gap. The mechanical displacement output by the giant magnetostrictive rod is directly transmitted to the magnetohydrodynamic pressurization device 803, thereby converting the mechanical displacement into test gas pulse pressure.

[0135] In this embodiment, the magnetostrictive device 802 includes an excitation coil and a super-magnetostrictive rod. The excitation coil generates an excitation magnetic field in response to a driving current. Under the influence of this magnetic field, the super-magnetostrictive rod deforms, generating mechanical displacement, which is output to the magnetohydrodynamic pressurization device 803 through a power output end formed at one end. Because the super-magnetostrictive material has the characteristics of fast response speed and large output force, it can achieve microsecond-level mechanical displacement output, thereby meeting the requirements of simulating the transient impact response of a target gas generator and improving the timeliness and accuracy of target pressure data reproduction.

[0136] Optionally, the magnetohydrodynamic (MHD) pressurization device 803 includes a pressurization cylinder, a pressurization piston, and a MHD sealing component. The pressurization cylinder has a gas outlet for connecting to the airbag. The pressurization piston is slidably disposed within the pressurization cylinder, with one end serving as the power input terminal of the MHD 803 and connected to the power output terminal of the magnetostrictive device 802. Driven by mechanical displacement, the piston reciprocates within the pressurization cylinder to compress the gas inside, and then outputs the compressed gas to the airbag through the gas outlet. The MHD sealing component is disposed between the pressurization piston and the inner wall of the pressurization cylinder, forming a sealing barrier during piston movement to prevent gas leakage from the pressurization cylinder.

[0137] The booster cylinder refers to the cylindrical cavity structure in the magnetohydrodynamic booster device 803 used to contain the gas. This cylinder is equipped with a gas outlet for connecting to the airbag to be tested. The booster cylinder provides guiding space for the reciprocating motion of the booster piston and withstands high pressure during the piston's gas compression process, delivering the compressed gas to the airbag through the gas outlet.

[0138] The booster piston is a movable component that slides within the booster cylinder. One end of the piston serves as the power input of the magnetohydrodynamic booster device 803, and is connected to the power output of the magnetostrictive device 802. The booster piston receives the mechanical displacement output by the magnetostrictive device 802 and, driven by this mechanical displacement, reciprocates within the booster cylinder, thereby compressing the gas within the cylinder. The compressed gas is then output to the airbag through the gas outlet.

[0139] Magnetohydrodynamic (MHD) sealing components refer to sealing assemblies located between the booster piston and the inner wall of the booster cylinder. They are used to form a dynamic sealing barrier when the booster piston moves, preventing high-pressure gas in the booster cylinder from leaking through the gap between the piston and the inner wall of the cylinder.

[0140] For example, in addition to the booster cylinder, booster piston, and magnetohydrodynamic sealing component, the magnetohydrodynamic booster device 803 also includes an output push rod. The output push rod is coaxially fixed to one end of the booster piston facing the magnetostrictive device 802. One end of the output push rod abuts against the power output end of the magnetostrictive device 802, and the other end is connected to the booster piston. As the power input end of the magnetohydrodynamic booster device 803, it can smoothly transmit the mechanical displacement output by the magnetostrictive device 802 to the booster piston, so that the thrust is transmitted evenly.

[0141] In this embodiment, the magnetohydrodynamic (MHD) booster device 803 includes a booster cylinder, a booster piston, and a MHD sealing component. Driven by mechanical displacement, the booster piston reciprocates within the booster cylinder, compressing gas and outputting it to the airbag through a gas outlet. The MHD sealing component forms a sealing barrier during the piston's movement, preventing gas leakage. Due to the use of MHD sealing technology, good sealing performance is maintained even during the piston's high-speed reciprocating motion, avoiding pressure loss caused by gas leakage and ensuring the stability and accuracy of the output pressure.

[0142] Optionally, the magnetohydrodynamic sealing component includes a permanent magnet ring and a magnetohydrodynamic fluid. The permanent magnet ring is disposed on the outer periphery of the booster piston; the magnetohydrodynamic fluid fills the space between the permanent magnet ring and the inner wall of the booster cylinder to form a sealing barrier under the action of the magnetic field generated by the permanent magnet ring.

[0143] The permanent magnet ring is a ring-shaped permanent magnet fitted around the outer circumference of the booster piston, used to generate a constant magnetic field in the surrounding space. This magnetic field acts on the magnetohydrodynamic fluid, causing it to form a sealing barrier in the tiny gap between the permanent magnet ring and the inner wall of the booster cylinder. This barrier effectively prevents gas in the booster cylinder from leaking along the gap between the piston and the inner wall of the cylinder.

[0144] Magnetofluids, also known as magnetic liquids or ferrofluids, are stable colloidal suspensions formed by uniformly dispersing nanoscale magnetic particles in a carrier liquid. Under the influence of an external magnetic field, magnetofluids exhibit magnetism and undergo directional aggregation, forming a solid-like sealing barrier.

[0145] In this embodiment, the magnetohydrodynamic (MHD) sealing component includes a permanent magnet ring and a magnetohydrodynamic fluid. The permanent magnet ring is disposed on the outer periphery of the booster piston, and the magnetohydrodynamic fluid fills the space between the permanent magnet ring and the inner wall of the booster cylinder, forming a sealing barrier under the action of the magnetic field generated by the permanent magnet ring. Since the MHD seal is a non-contact seal, there is almost no mechanical wear during piston movement, thus maintaining a stable sealing effect for a long time, improving the reliability and service life of the equipment.

[0146] In this embodiment, the airbag testing system 800 includes a processor 801, a magnetostrictive device 802, and a magnetohydrodynamic pressurization device 803. The processor 801 acquires target pressure data and pressure output characteristics, determines the driving current, and outputs it to the magnetostrictive device 802. The magnetostrictive device 802 generates mechanical displacement in response to the driving current. The magnetohydrodynamic pressurization device 803 converts the mechanical displacement into gas pulse pressure and outputs it to the airbag. Through the coordinated operation of these components, a fully electrically driven airbag test is achieved. Since there is no need to consume a propellant gas generator, the testing cost is significantly reduced; at the same time, the safety risks caused by propellant explosion are avoided, improving testing safety; furthermore, the output pressure curve can be flexibly adjusted by precisely controlling the driving current, ensuring the consistency and repeatability of the test results.

[0147] Please refer to Figure 9 , Figure 9 This diagram illustrates the layered architecture of an airbag testing system provided in some embodiments of this application. The system is divided into seven layers from top to bottom: user layer, sensor layer, control layer, auxiliary system, execution layer, pressurization layer, and the object under test. The layering is explained below: I. User Layer: This layer comprises two main modules: a human-machine interface and a target curve database. The human-machine interface allows operators to set parameters such as generator model, temperature, and aging mode, and to select and send Pt curves. The target curve database stores pressure data for various gas generator models and can output standard Pt curve data to the control layer.

[0148] II. Sensor Layer: Responsible for real-time acquisition of physical quantities across the entire area, including two types of high-precision sensors. The PT100 temperature sensor acquires the real-time ambient temperature and uploads the temperature signal to the control layer for temperature compensation calculations; the 200kHz sampling rate high-frequency pressure sensor acquires the actual pressure output from the pressurization chamber in real time, transmits the real-time pressure signal back to the control layer, and simultaneously pushes the complete actual pressure curve to the auxiliary system for display and storage.

[0149] III. Control Layer: It consists of three hardware levels connected in series: a DSP (Digital Signal Processor) algorithm processor, an FPGA real-time controller, and a high-frequency PWM (Pulse Width Modulation) power driver, with a sampling period of 5μs.

[0150] The DSP algorithm processor receives standard Pt data from the user layer, executes aging model correction, temperature compensation, and nonlinear inverse compensation algorithms, generates the target drive waveform for the corresponding operating condition, and sends it to the FPGA. The FPGA real-time controller, as the core of closed-loop control, receives the DSP target waveform and real-time pressure signal from the sensor layer to complete pressure deviation calculation and current correction. On the other hand, it outputs PWM control signals to the power drive module. The high-frequency PWM power drive supports 0~100A output and 5μs fast response. It receives the PWM control signal from the FPGA, amplifies it into a high-current drive signal, and outputs it to the lower-level actuator.

[0151] IV. Auxiliary System: This includes a low-pressure gas source and a data acquisition system. The low-pressure gas source provides low-pressure compensation gas to the pressurization layer, enabling unidirectional gas replenishment to the pressurization chamber, with a pressure range of 0.5~2MPa. The data acquisition system receives actual pressure curves uploaded by a high-frequency pressure sensor, completing real-time display and archiving of test data. The data acquisition frequency is greater than or equal to 200kHz.

[0152] 5. The execution layer receives the high-current drive signal output from the control layer and outputs micron-level mechanical thrust step by step. Among them, the excitation coil generates a controllable excitation magnetic field after the high-current drive is applied; the giant magnetostrictive rod generates a ±200μm microsecond-level telescopic displacement under the action of the magnetic field, with a maximum output thrust of 5000N; the pressurizing piston receives the axial displacement of the giant magnetostrictive rod and outputs mechanical compression thrust, which is then transmitted to the pressurizing layer cavity.

[0153] VI. The pressurization layer receives the mechanical thrust from the execution layer and the low-pressure gas source from the auxiliary system, generating a high-pressure gas pulse. A one-way gas supply valve connects the low-pressure gas source to the pressurization chamber, enabling one-way air intake and low-pressure pre-charging of the chamber. A magnetohydrodynamic sealing component is positioned between the pressurization piston and the inner wall of the pressurization chamber, achieving dynamic high-pressure sealing during the piston's reciprocating motion and preventing high-pressure gas leakage from the chamber. The pressurization chamber receives the mechanical compression from the pressurization piston, causing the internal gas to be pressurized and boosted, capable of outputting a high-pressure gas pulse of up to 30 MPa. This high-pressure pulse is directly delivered downwards to the tested airbag.

[0154] 7. The object under test, namely the airbag to be tested, receives the high-pressure gas pulse output from the pressurization layer and completes the equivalent impact simulation test of the gas generator.

[0155] Overall signal and power flow logic: The operator selects the target curve at the user level → the DSP algorithm processor completes the working condition compensation calculation to generate the drive waveform → the FPGA real-time controller corrects the output PWM control signal in real time through closed loop → the power drive amplifies the signal into a large current to drive the magnetostrictive mechanism to generate micron-level thrust → the pressurizing piston compresses the pressurizing chamber → the low-pressure air source assists in air replenishment and the magnetofluid seals and maintains pressure → the chamber outputs a high-pressure pulse to impact the safety airbag; throughout the process, temperature and pressure sensors collect physical quantities in real time and transmit them back to the control layer to form a closed loop, and the test data is synchronously uploaded to the auxiliary system for storage and display.

[0156] To verify the actual performance of the airbag testing method and system provided in this application, a gunpowder gas generator was selected as the test object, and equivalent simulation tests under multiple operating conditions were conducted. The specific details of the test cases are as follows: 1. Test Object Target gas generator: TRW ABG-123 driver-side single-stage explosive airbag gas generator.

[0157] Target gas generator parameters: peak pressure 12.5MPa, pressurization time 2.5ms (0→12.5MPa), total charging time 15ms, reference temperature 23℃, generator volume 80cm³.

[0158] Test conditions: ambient temperature (23℃), high temperature (85℃), low temperature (-40℃).

[0159] Aging simulation: Performance degradation after 500 equivalent explosions.

[0160] Equipment parameters: Please refer to Table 1 Table 1

[0161] 2. Testing Process Initialization: The low-pressure gas source fills the pressurization chamber with gas at a base pressure of 1.0 MPa, and the magnetohydrodynamic seal is formed.

[0162] Parameter loading: The host computer reads the standard Pt curve of the target generator. The sampling interval of this curve is 10μs, with a total of 1500 points.

[0163] Temperature compensation: If the temperature is not the reference value, the system automatically calculates the compensation coefficient based on the built-in temperature compensation model and corrects the target curve.

[0164] Nonlinear inverse compensation: Based on the Preisach inverse model, the target pressure curve is converted into a feedforward drive current waveform.

[0165] Real-time control: The FPGA outputs drive current in 5μs cycles, while the pressure sensor provides real-time feedback. The PID algorithm calculates the current correction, forming a composite control.

[0166] Data recording: After the test is completed, the target curve, actual output curve, drive current, and deviation data are automatically saved.

[0167] 3. Experimental Results 3.1 Under normal operating conditions (23℃), please refer to Table 2 for the results.

[0168] Table 2

[0169] 3.2 Full temperature range adaptability, please refer to Table 3 for the results.

[0170] Table 3

[0171] 3.3 Repeatability test: 23℃ at room temperature, 10 times consecutively. Please refer to Table 4 for the results.

[0172] Table 4

[0173] 3.4 Aging simulation (equivalent to 500 explosions), please refer to Table 5 for the results.

[0174] Table 5

[0175] 3.5 Lifespan and Reliability Magnetohydrodynamic sealing: After 1 million reciprocating motion tests, the leakage rate is still 0 mL / min, and the sealing performance has not degraded.

[0176] Magnetostrictive rod: After 1 million cycles, the output force decreases by less than 2%, and the displacement linearity remains good.

[0177] Excitation coil: Under pulse duty cycle (5%), the temperature rise is ≤15℃ and the insulation resistance remains unchanged.

[0178] 3.6 For comparison data with related technologies, please refer to Table 6.

[0179] Table 6

[0180] 3.7 Experimental Conclusions This experiment fully verifies the effectiveness of the technical solution proposed in this application: Accuracy: Peak pressure error at room temperature ≤0.64%, and error across the entire temperature range ≤1.2%, fully meeting the requirements for pressure curve replication in airbag testing.

[0181] Repeatability: The coefficient of variation is ≤0.8%, which ensures the consistency and comparability of the test results.

[0182] Functionality expansion: Successfully simulated old chemical conditions, expanding the testing dimensions.

[0183] Economic efficiency: The cost of a single test is only 4% of that of traditional gunpowder solutions, and the equipment has a lifespan of over 1 million tests, significantly reducing R&D and testing costs.

[0184] Safety: Fully electrically driven, with no risk of explosion, and can be safely operated in ordinary laboratory environments.

[0185] This application has at least the following beneficial effects: I. Microsecond-level accurate reproduction of gunpowder gas generator characteristics: This application is the first to combine super magnetostrictive materials with magnetohydrodynamic sealing technology to construct a feedforward and feedback composite control system, which realizes the accurate reproduction of the pressure-time curve of the gunpowder gas generator.

[0186] II. Full-temperature-range adaptive equivalent simulation: This application has a built-in temperature compensation algorithm that can accurately reproduce the output characteristics of the gunpowder gas generator at different temperatures within a wide temperature range of -40℃ to 120℃.

[0187] 3. Full life cycle programmable simulation capability: This application supports user-defined editing of inflation curves and can simulate extreme working conditions such as aging and failure of gunpowder gas generators.

[0188] IV. Significantly Reduced Testing Costs and Improved R&D Efficiency: In conventional real-world gunpowder detonation tests, a single test requires one gas generator and one safety airbag, with a total cost of approximately 300-600 yuan per test. This application uses an all-electric drive, consuming only electricity and a very small amount of low-pressure gas per test, reducing the cost per test by more than 95%.

[0189] In addition, this application also proposes a storage medium, which is a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the airbag testing method described above.

[0190] In addition, this application also proposes a computer program product, which includes a computer program that, when executed by a processor, implements the steps of the airbag testing method described above.

[0191] It should be noted that the workflow described above is merely illustrative and does not limit the scope of protection of this application. In practical applications, those skilled in the art can select some or all of it to achieve the purpose of this embodiment according to actual needs, and no restrictions are imposed here.

[0192] In addition, for technical details not described in detail in this embodiment, please refer to the airbag testing method provided in any embodiment of this application, which will not be repeated here.

[0193] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for testing airbags, characterized in that, An airbag testing system is used, the system including a processor, a magnetostrictive device electrically connected to the processor, and a magnetohydrodynamic pressurization device mechanically coupled to the magnetostrictive device; The method is executed by the processor, and the method includes: Acquire target pressure data, which characterizes the change in the required inflation pressure of the airbag to be tested over time; The pressure output characteristics of the airbag testing system are obtained, and the pressure output characteristics characterize the mapping relationship between the driving current of the magnetostrictive device and the output pressure of the magnetohydrodynamic pressurization device. The target pressure at each moment in the target pressure data is taken as the desired output pressure of the magnetohydrodynamic booster device, and based on the pressure output characteristics, the driving current of the magnetostrictive device corresponding to the desired output pressure is determined; and The driving current is output to the magnetostrictive device to drive the magnetostrictive device to generate mechanical displacement, and the mechanical displacement is converted into gas pulse pressure and output to the airbag through the magnetohydrodynamic pressurization device to test the airbag.

2. The method as described in claim 1, characterized in that, The acquisition of target pressure data includes: Obtain standard pressure data at standard temperature; Get the current ambient temperature; Determine the temperature compensation parameters corresponding to the current ambient temperature; and Based on the temperature compensation parameters, the pressure at each moment in the standard pressure data is corrected to obtain target pressure data that is adapted to the current ambient temperature.

3. The method as described in claim 2, characterized in that, The determination of the temperature compensation parameter corresponding to the current ambient temperature includes: Obtain the gas compressibility factor corresponding to the current ambient temperature and the gas compressibility factor corresponding to the standard temperature; and The temperature compensation parameter is determined based on the ratio of the current ambient temperature to the standard temperature, the ratio of the gas compressibility factor corresponding to the current ambient temperature to the gas compressibility factor corresponding to the standard temperature, and the gas generation rate temperature coefficient of the target gas generator.

4. The method as described in claim 1, characterized in that, The acquisition of target pressure data includes: Acquire standard pressure data of the target gas generator in its initial state; Determine the aging correction parameters corresponding to the aging degree of the target gas generator; and The pressure at each moment in the standard pressure data is corrected based on the aging correction parameters to obtain the target pressure data of the target gas generator under aging conditions.

5. The method according to any one of claims 1-4, characterized in that, After outputting the driving current to the magnetostrictive device, the method further includes: Collect the actual pressure output from the magnetohydrodynamic pressurization device to the airbag at the current moment; Determine the pressure deviation between the actual pressure and the target pressure corresponding to the current moment; and The current correction amount is determined based on the pressure deviation, and the current correction amount is added to the drive current at the next moment.

6. The method according to claim 5, characterized in that, The step of determining the current correction amount based on the pressure deviation includes: Obtain the pressure deviation from the previous moment and the cumulative pressure deviation from the current moment; and The current correction amount is determined based on the pressure deviation at the current moment, the pressure deviation at the previous moment, and the cumulative value.

7. The method according to any one of claims 1-4, characterized in that, The process of obtaining the pressure output characteristics of the airbag testing system includes: Multiple static currents of different amplitudes are input into the magnetostrictive device, the corresponding steady-state pressures are measured, and a static mapping relationship between the static currents and the steady-state pressures is established. A dynamic current that varies with time is input into the magnetostrictive device, the corresponding dynamic pressure is measured, and a dynamic mapping relationship between the dynamic current and the dynamic pressure is established; and Based on the static mapping relationship and the dynamic mapping relationship, the pressure output characteristics of the airbag testing system are constructed.

8. An airbag testing system, characterized in that, The system includes a processor, a magnetostrictive device, and a magnetohydrodynamic pressurization device; The processor is electrically connected to the magnetostrictive device, and the power output end of the magnetostrictive device is drive-connected to the power input end of the magnetohydrodynamic booster device. The processor is configured to acquire target pressure data, which characterizes the change in the required inflation pressure of the airbag under test over time; acquire the pressure output characteristics of the airbag testing system, which characterizes the mapping relationship between the driving current of the magnetostrictive device and the output pressure of the magnetohydrodynamic pressurization device; use the target pressure at each moment in the target pressure data as the desired output pressure of the magnetohydrodynamic pressurization device, and determine the driving current of the magnetostrictive device corresponding to the desired output pressure based on the pressure output characteristics; The driving current is output to the magnetostrictive device; The magnetostrictive device is used to receive and respond to the driving current to generate mechanical displacement, and output the mechanical displacement to the magnetohydrodynamic pressurization device through the power output terminal; as well as The magnetohydrodynamic pressurization device is used to receive the mechanical displacement through the power input terminal, convert the mechanical displacement into gas pulse pressure and output it to the airbag to test the airbag.

9. The system as described in claim 8, characterized in that, The magnetostrictive device includes an excitation coil and a super magnetostrictive rod; The excitation coil is sleeved on the outer periphery of the super magnetostrictive rod and is used to generate an excitation magnetic field in response to the driving current. as well as One end of the super magnetostrictive rod forms the power output end of the magnetostrictive device, which abuts against the power input end of the magnetohydrodynamic pressurization device. It is used to deform under the action of the excitation magnetic field to generate the mechanical displacement, and output the mechanical displacement to the power input end of the magnetohydrodynamic pressurization device through the power output end.

10. The system according to any one of claims 8-9, characterized in that, The magnetohydrodynamic booster device includes a booster cylinder, a booster piston, and a magnetohydrodynamic sealing component; The booster cylinder is provided with a gas outlet, which is used to connect to the airbag. The booster piston is slidably disposed in the booster cylinder, with one end serving as the power input end of the magnetohydrodynamic booster device and being connected to the power output end of the magnetostrictive device. It is used to reciprocate within the booster cylinder under the drive of the mechanical displacement to compress the gas within the booster cylinder and output the compressed gas to the airbag through the gas output port. as well as The magnetohydrodynamic sealing component is disposed between the booster piston and the inner wall of the booster cylinder, and is used to form a sealing barrier when the booster piston moves to prevent gas leakage from the booster cylinder.

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