Dynamic engine sound simulation system and method and storage medium

Abstract

The embodiment of the invention provides a dynamic engine sound simulation system and method and a storage medium, and belongs to the technical field of vehicle electronic control. The system comprises a signal acquisition unit used for acquiring an engine rotating speed signal and an accelerator opening degree signal; the processing control unit is in signal connection with the signal acquisition unit and is used for generating sound wave control parameters based on the engine rotating speed signal and the accelerator opening degree signal; the PWM waveform generation unit is in signal connection with the processing control unit and is used for generating a corresponding PWM driving signal based on the sound wave control parameter; and the passive buzzer is electrically connected with the PWM waveform generation unit and is used for outputting corresponding engine sound wave simulation sound based on the PWM driving signal. According to the scheme, under the conditions of low hardware cost and controllable system complexity, real-time nonlinear mapping between engine operation parameters and sound wave output is achieved, engine sound waves can dynamically respond to driver operation, and continuous and stable acoustic performance is kept.

Description

Technical Field

[0001] This invention relates to the field of vehicle electronic control technology, specifically to a dynamic engine sound simulation system, a dynamic engine sound simulation method, and a storage medium. Background Technology

[0002] With the increasing demand for vehicle intelligence and personalization, engine sound simulation technology has gradually become an important component of vehicle electronic systems. Currently, vehicle engine sound simulation mainly employs two technical solutions. One is an audio playback solution, which uses pre-recorded or pre-stored high-fidelity engine sound audio files, played through the in-vehicle audio system or external speakers in specific driving modes. This solution can achieve good sound quality, but it relies on a high-fidelity audio system and power amplifier, resulting in high hardware costs. Furthermore, the audio content is usually a fixed segment, making it difficult to dynamically adjust according to the driver's real-time operations, leading to response delays.

[0003] Another type is the real-time synthesis scheme based on an accurate physical model. This scheme establishes a physical model of the engine and calculates the sound waveform in real time based on parameters such as engine speed and load. This scheme has a certain degree of real-time performance, but the algorithm structure is complex, it requires high processor computing power, the system development and debugging are difficult, and the adaptation cost between different engines is high.

[0004] Therefore, how to achieve nonlinear mapping of operating parameters such as engine speed and throttle opening, and generate dynamic sound output that can respond to driver operation in real time, under the premise of controllable control system complexity and hardware cost, has become an urgent technical problem to be solved. Summary of the Invention

[0005] The purpose of this invention is to provide a dynamic engine sound simulation system, method, and storage medium to at least solve the problems of high cost, high system complexity, and difficulty in real-time nonlinear response to driver operation in the prior art.

[0006] To achieve the above objectives, a first aspect of the present invention provides a dynamic engine sound simulation system, the system comprising: a signal acquisition unit for acquiring engine speed signals and throttle opening signals; a processing control unit connected to the signal acquisition unit for generating sound control parameters based on the engine speed signals and the throttle opening signals; a PWM waveform generation unit connected to the processing control unit for generating corresponding PWM drive signals based on the sound control parameters; and a passive buzzer electrically connected to the PWM waveform generation unit for outputting a corresponding simulated engine sound based on the PWM drive signals.

[0007] Optionally, the processing control unit includes a signal preprocessing module for performing normalization processing on the engine speed signal and the throttle opening signal, and calculating the throttle opening change based on the throttle opening signal at continuous sampling times; the signal preprocessing module outputs the normalized engine speed signal, the normalized throttle opening signal, and the throttle opening change to the sound control parameter generation module in the processing control unit.

[0008] Optionally, the sound wave control parameter generation module is a fuzzy logic control module; the fuzzy logic control module is used to map the normalized engine speed signal and the normalized throttle opening signal to a preset fuzzy linguistic variable set respectively; perform fuzzy inference operation and defuzzification operation based on a preset rule base to generate the sound wave control parameters used to characterize the sound wave frequency parameter and the sound wave amplitude parameter, and output the sound wave control parameters to the PWM waveform generation unit.

[0009] Optionally, when the sound wave control parameter generation module performs fuzzy inference and defuzzification operations based on a preset rule base to generate the sound wave control parameters characterizing the sound wave frequency and amplitude parameters, it is configured to: establish a set of resonance anchor points corresponding to engine speed zones in the preset rule base, each set of resonance anchor points corresponding to at least one preset speed zone and a target sound wave fundamental frequency anchor point value and a target sound wave amplitude anchor point value corresponding to the preset speed zone; after generating the sound wave control parameters, obtain the sound wave frequency and amplitude parameters from the sound wave control parameters, and call the corresponding set of resonance anchor points according to the preset speed zone to which the current engine speed belongs; and convert the sound wave... The frequency parameter is matched with the target sound wave fundamental frequency anchor value to calculate the frequency offset, and constraint correction is performed based on the frequency offset to generate the corrected sound wave frequency parameter; the sound wave amplitude parameter is matched with the target sound wave amplitude anchor value to calculate the amplitude offset, and constraint correction is performed based on the amplitude offset to generate the corrected sound wave amplitude parameter; the rate of change of the corrected sound wave frequency parameter and the corrected sound wave amplitude parameter are calculated respectively within a continuous sampling period, and envelope smoothing is performed respectively when the corresponding rate of change exceeds a preset continuity threshold to generate the final sound wave frequency parameter and the final sound wave amplitude parameter; the final sound wave frequency parameter and the final sound wave amplitude parameter are updated to the sound wave control parameter.

[0010] Optionally, the PWM waveform generation unit is used to generate a base frequency PWM signal based on the sound wave frequency parameter, and modulate the duty cycle of the base frequency PWM signal based on the sound wave amplitude parameter to generate a PWM drive signal for driving the passive buzzer, and output the PWM drive signal to the passive buzzer.

[0011] Optionally, the sound wave control parameters further include harmonic control parameters; the PWM waveform generation unit is used to perform harmonic superposition processing on the fundamental frequency PWM signal based on the harmonic control parameters, generate a synthetic PWM drive signal containing at least one higher harmonic component, and output the synthetic PWM drive signal to the passive buzzer.

[0012] Optionally, the processing control unit further includes a mode management module; the mode management module is used to perform switching operations between preset operating modes, and when switching modes, it calls the preset rule base and preset parameter set of the corresponding operating mode to update the control rules of the sound wave control parameter generation module, and applies the updated control rules to the sound wave control parameter generation process.

[0013] A second aspect of the present invention provides a method for simulating dynamic engine sound, the method being implemented based on the aforementioned dynamic engine sound simulation system. The method includes: acquiring an engine speed signal and a throttle opening signal, and performing normalization processing on the engine speed signal and the throttle opening signal to generate normalized engine speed signals and normalized throttle opening signals; performing sound control parameter generation calculations based on the normalized engine speed signal and the normalized throttle opening signal to generate sound control parameters including sound frequency parameters and sound amplitude parameters; generating a fundamental frequency PWM signal based on the sound frequency parameters, and performing duty cycle modulation on the fundamental frequency PWM signal based on the sound amplitude parameters to generate a PWM drive signal; and outputting the PWM drive signal to a passive buzzer to output a corresponding simulated engine sound based on the PWM drive signal.

[0014] Optionally, a sound wave control parameter generation operation is performed based on the normalized engine speed signal and the normalized throttle opening signal to generate sound wave control parameters including sound wave frequency parameters and sound wave amplitude parameters. This includes: calculating the throttle opening change based on the throttle opening signal at continuously sampled times, and mapping the normalized engine speed signal, the normalized throttle opening signal, and the throttle opening change to a preset fuzzy linguistic variable set; performing fuzzy inference and defuzzification operations based on a preset rule base to generate the sound wave control parameters characterizing the sound wave frequency parameters and sound wave amplitude parameters; establishing a set of resonance anchor points corresponding to engine speed zones in the preset rule base, where each set of resonance anchor points corresponds to at least one preset speed range and a target sound wave fundamental frequency anchor point value and a target sound wave amplitude anchor point value corresponding to the preset speed range; after generating the sound wave control parameters... The sound wave frequency parameter and sound wave amplitude parameter are obtained from the sound wave control parameters, and the corresponding resonance anchor point set is called according to the preset speed range to which the current engine speed belongs; the sound wave frequency parameter is matched with the target sound wave fundamental frequency anchor point value to calculate the frequency offset, and constraint correction is performed based on the frequency offset to generate the corrected sound wave frequency parameter; the sound wave amplitude parameter is matched with the target sound wave amplitude anchor point value to calculate the amplitude offset, and constraint correction is performed based on the amplitude offset to generate the corrected sound wave amplitude parameter; the rate of change of the corrected sound wave frequency parameter and the corrected sound wave amplitude parameter are calculated respectively within a continuous sampling period, and envelope smoothing is performed respectively when the corresponding rate of change exceeds a preset continuity threshold to generate the final sound wave frequency parameter and the final sound wave amplitude parameter; the final sound wave frequency parameter and the final sound wave amplitude parameter are updated to the sound wave control parameters.

[0015] On the other hand, the present invention provides a computer-readable storage medium storing instructions that, when executed on a computer, cause the computer to perform the above-described dynamic engine sound simulation method.

[0016] Through the above technical solution, this invention acquires engine speed and throttle opening signals, generates sound control parameters using a processing control unit, and drives a passive buzzer to output engine sound through a PWM waveform generation unit, thus achieving real-time correlation between engine operating parameters and sound output. Compared to audio playback solutions relying on high-fidelity audio systems and complex physical modeling solutions, this invention adopts a PWM drive structure based on control parameters, reducing hardware costs and system complexity while improving the response speed to changes in driver operation. This allows the sound output to dynamically adjust with changes in engine speed and throttle opening, achieving a balance between cost, real-time performance, and feasibility while ensuring controllable implementation difficulty.

[0017] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0019] Figure 1 This is a system structure diagram of a dynamic engine sound simulation system provided in one embodiment of the present invention; Figure 2 This is a flowchart of the steps of a dynamic engine sound simulation method provided in one embodiment of the present invention. Detailed Implementation

[0020] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0021] Figure 1 This is a system structure diagram of a dynamic engine sound simulation system provided in one embodiment of the present invention. Figure 1 As shown, this invention provides a dynamic engine sound simulation system, comprising: a signal acquisition unit for acquiring engine speed signals and throttle opening signals; a processing control unit connected to the signal acquisition unit for generating sound control parameters based on the engine speed signals and the throttle opening signals; a PWM waveform generation unit connected to the processing control unit for generating corresponding PWM drive signals based on the sound control parameters; and a passive buzzer electrically connected to the PWM waveform generation unit for outputting a corresponding simulated engine sound based on the PWM drive signal.

[0022] In this embodiment of the invention, the dynamic engine sound simulation system acquires engine speed and throttle opening signals in real time through a signal acquisition unit, and inputs these signals to a processing control unit. The processing control unit generates sound control parameters based on the engine speed and throttle opening signals, establishing a parameter-level correlation between the sound output and the engine operating state. The PWM waveform generation unit generates a corresponding PWM drive signal according to the sound control parameters and outputs the PWM drive signal to a passive buzzer. The passive buzzer outputs simulated engine sound under the drive of the PWM drive signal. Through this structure, the present invention achieves dynamic sound simulation based on engine operating parameters without relying on a high-fidelity audio playback system or complex physical modeling algorithms.

[0023] Preferably, the processing control unit includes a signal preprocessing module, which performs normalization processing on the engine speed signal and the throttle opening signal, and calculates the throttle opening change based on the throttle opening signal at continuous sampling time; the signal preprocessing module outputs the normalized engine speed signal, the normalized throttle opening signal, and the throttle opening change to the sound control parameter generation module in the processing control unit.

[0024] Furthermore, the sound wave control parameter generation module is a fuzzy logic control module; the fuzzy logic control module is used to map the normalized engine speed signal and the normalized throttle opening signal to a preset fuzzy linguistic variable set respectively; perform fuzzy inference operation and defuzzification operation based on the preset rule base to generate the sound wave control parameters used to characterize the sound wave frequency parameter and the sound wave amplitude parameter, and output the sound wave control parameters to the PWM waveform generation unit.

[0025] Furthermore, when the sound wave control parameter generation module generates the sound wave control parameters characterizing the sound wave frequency parameters and sound wave amplitude parameters by performing fuzzy inference and defuzzification operations based on a preset rule base, it is configured to: establish a set of resonance anchor points corresponding to engine speed zones in the preset rule base, each set of resonance anchor points corresponding to at least one preset speed zone and a target sound wave fundamental frequency anchor point value and a target sound wave amplitude anchor point value corresponding to the preset speed zone; after generating the sound wave control parameters, obtain the sound wave frequency parameters and sound wave amplitude parameters from the sound wave control parameters, and call the corresponding set of resonance anchor points according to the preset speed zone to which the current engine speed belongs; and then... The wave frequency parameter is matched with the target wave fundamental frequency anchor value to calculate the frequency offset, and constraint correction is performed based on the frequency offset to generate the corrected wave frequency parameter; the wave amplitude parameter is matched with the target wave amplitude anchor value to calculate the amplitude offset, and constraint correction is performed based on the amplitude offset to generate the corrected wave amplitude parameter; the rate of change of the corrected wave frequency parameter and the corrected wave amplitude parameter are calculated respectively within a continuous sampling period, and envelope smoothing is performed respectively when the corresponding rate of change exceeds a preset continuity threshold to generate the final wave frequency parameter and the final wave amplitude parameter; the final wave frequency parameter and the final wave amplitude parameter are updated to the wave control parameter.

[0026] In this embodiment of the invention, the processing control unit is internally equipped with a signal preprocessing module. The signal preprocessing module performs normalization processing on the engine speed signal and the throttle opening signal to eliminate the impact of differences in vehicle models, engine specifications, and sensor output ranges on subsequent control algorithms. The engine speed signal is linearly mapped according to a preset lower speed limit and a preset upper speed limit to generate a normalized engine speed signal; the throttle opening signal is linearly mapped according to a preset lower opening limit and a preset upper opening limit to generate a normalized throttle opening signal. The aforementioned preset numerical ranges can be set according to specific vehicle models. For example, in one embodiment, the engine speed range can be mapped to between 0 and 1, and the throttle opening range can be mapped to between 0 and 1, thereby unifying the input scale for subsequent fuzzy logic operations.

[0027] Within a continuous sampling period, the signal preprocessing module calculates the throttle opening change based on the normalized throttle opening signals at adjacent sampling times. This throttle opening change is obtained by subtracting the normalized throttle opening signal from the previous sampling time from the current sampling time's normalized throttle opening signal. This throttle opening change reflects the driver's operational trend; for example, if the throttle opening increases from 0.35 to 0.55 within two consecutive sampling periods, the throttle opening change is 0.20, a value used to characterize the intensity of acceleration intention. The normalized engine speed signal, the normalized throttle opening signal, and the throttle opening change are simultaneously output to the sound control parameter generation module, providing both state and change inputs for subsequent sound control parameter generation.

[0028] In this embodiment, the sound control parameter generation module is configured as a fuzzy logic control module. This fuzzy logic control module maps the normalized engine speed signal and the normalized throttle opening signal to a preset set of fuzzy linguistic variables. The preset set of fuzzy linguistic variables may include several linguistic variables describing engine speed ranges and several linguistic variables describing throttle opening ranges. Each linguistic variable is numerically mapped using a preset membership function, such as a triangular or trapezoidal membership function. The change in throttle opening can also participate in the fuzzy inference process to enhance the responsiveness to instantaneous changes in driver operation.

[0029] Based on a preset rule base, fuzzy inference and defuzzification operations are performed to generate the sound wave control parameters, which characterize the sound wave frequency and amplitude parameters. The preset rule base can be set according to the engine type. For example, in one embodiment, when the engine speed is in the mid-to-high range and the throttle opening is large, the corresponding sound wave frequency parameter is set to a relatively high range, while the sound wave amplitude parameter is set to a large range. The defuzzification operation can use the centroid method or the weighted average method to obtain continuous numerical output. The generated sound wave control parameters are then output to the PWM waveform generation unit.

[0030] To improve the matching degree between the simulated sound wave and the acoustic characteristics of a real engine, a set of resonance anchor points corresponding to engine speed zones is further set within the sound wave control parameter generation module. Each set of resonance anchor points corresponds to at least one preset speed range and includes a target sound wave fundamental frequency anchor point value and a target sound wave amplitude anchor point value. The target sound wave fundamental frequency anchor point value is used to define the center value of the sound wave frequency within the speed range, and the target sound wave amplitude anchor point value is used to define the reference value of the sound wave intensity within the speed range. For example, in one embodiment, a low speed range corresponds to a lower fundamental frequency anchor point value and a smaller amplitude anchor point value, while a high speed range corresponds to a higher fundamental frequency anchor point value and a larger amplitude anchor point value.

[0031] After generating the sound wave control parameters, the sound wave frequency parameters and sound wave amplitude parameters are obtained from the sound wave control parameters, and the corresponding resonance anchor point set is called according to the preset speed range to which the current engine speed belongs. The sound wave frequency parameters are matched with the target sound wave fundamental frequency anchor point value to calculate the frequency offset. The frequency offset is used to characterize the degree of deviation of the current sound wave frequency parameters relative to the target sound wave fundamental frequency anchor point value. Based on the frequency offset, constraint correction is performed to generate corrected sound wave frequency parameters. The correction process can adopt a proportional correction method, for example, scaling the offset by a preset proportional coefficient and then superimposing it onto the target sound wave fundamental frequency anchor point value.

[0032] Similarly, the acoustic wave amplitude parameter is matched with the target acoustic wave amplitude anchor point value to calculate the amplitude offset, and constraint correction is performed based on the amplitude offset to generate a corrected acoustic wave amplitude parameter. Through the above-mentioned dual-parameter constraint mechanism, the acoustic wave frequency parameter and the acoustic wave amplitude parameter fluctuate around the corresponding anchor point value in different speed ranges, thereby maintaining the stability of the overall acoustic wave structure.

[0033] The rate of change of the corrected sound wave frequency parameter and the corrected sound wave amplitude parameter are calculated separately within a continuous sampling period. When the rate of change exceeds a preset continuity threshold, envelope smoothing is performed on the corresponding parameter. The envelope smoothing can be implemented using a moving average filter or a first-order low-pass filter to limit the parameter variation amplitude between adjacent sampling periods. For example, in one embodiment, if the frequency change rate exceeds the preset threshold, a weighted average is taken between the final sound wave frequency parameter of the previous sampling period and the current corrected sound wave frequency parameter to generate the final sound wave frequency parameter. The amplitude parameter is processed similarly. Finally, the final sound wave frequency parameter and the final sound wave amplitude parameter are updated to the sound wave control parameters for subsequent use by the PWM waveform generation unit.

[0034] The above technical solution constructs a nonlinear mapping relationship between engine operating parameters and sound output parameters through normalization processing, fuzzy inference, and a two-parameter constraint mechanism based on a set of resonance anchor points. Simultaneously, it controls parameter mutations through a continuity constraint mechanism, forming a stable, adjustable, and real-time responsive sound control parameter generation process. The number of resonance anchor points, the speed range division method, and the anchor point values ​​can all be set according to the specific engine type. The matching operation and correction method can also be implemented using equivalent mathematical expressions, all of which fall within the scope of protection of this invention.

[0035] In a lightweight implementation, the collected engine speed (RPM) and throttle opening (Throttle) are standardized, for example, by linearly mapping the RPM and throttle opening to a preset range of 0 to 1, and used as input variables for the fuzzy logic controller. The throttle change rate (ΔThrottle) is obtained by performing a differential operation on the throttle opening within a continuous sampling period, and is used to reflect the trend of driver operation changes.

[0036] In the fuzzy logic dynamic control process, fuzzification is performed first. The standardized engine speed is mapped to the engine speed fuzzy set {low, medium, high}; the standardized throttle opening is mapped to the throttle fuzzy set {light, medium, heavy}; and the throttle change rate is mapped to the throttle change rate fuzzy set {gradual, moderate, rapid acceleration}. Each fuzzy set can be defined using triangular or trapezoidal membership functions. For example, when the standardized engine speed is 0.8, its membership degree in the "high" fuzzy set is relatively high; when the throttle change rate increases from 0.2 to 0.6 in a short time, its membership degree in the "rapid acceleration" fuzzy set increases.

[0037] Subsequently, inference operations are performed based on a preset fuzzy rule base. This fuzzy rule base is established based on expert experience and real-vehicle tuning data, and the rule format is "IF…AND…THEN…". For example: IF high engine speed AND rapid acceleration THEN a sharp increase in engine noise frequency and volume; IF medium engine speed AND medium throttle opening THEN a moderate engine noise frequency and stable volume; IF low engine speed AND gradual throttle change THEN a low engine noise frequency and gentle volume. These rules can be adapted to different vehicle models.

[0038] After completing fuzzy inference, the centroid method is used for defuzzification, converting the fuzzy output into precise control quantities to generate the target fundamental frequency and volume gain. The target fundamental frequency is used to control the PWM fundamental frequency, and the volume gain is used to modulate the PWM duty cycle. Through this lightweight processing path, dynamic response to changes in engine speed and throttle can be achieved on a relatively low-power computing platform, enabling real-time sound simulation.

[0039] Preferably, the PWM waveform generation unit is used to generate a base frequency PWM signal based on the sound wave frequency parameter, and modulate the duty cycle of the base frequency PWM signal based on the sound wave amplitude parameter to generate a PWM drive signal for driving the passive buzzer, and output the PWM drive signal to the passive buzzer.

[0040] In this embodiment of the invention, the PWM waveform generation unit is used to generate a fundamental frequency PWM signal corresponding to the sound wave frequency parameter. The sound wave frequency parameter is obtained by the processing control unit based on fuzzy logic reasoning, and its value corresponds to the fundamental frequency value of the target sound wave. The PWM waveform generation unit sets the timer counting period according to the sound wave frequency parameter and generates a PWM square wave signal with a corresponding frequency. This PWM square wave signal serves as the basic driving waveform and is used to control the vibration frequency of the passive buzzer.

[0041] To enhance the layering of the simulated sound waves, the PWM waveform generation unit modulates the duty cycle of the fundamental frequency PWM signal based on the sound wave amplitude parameters, building upon the fundamental frequency PWM signal generation. By adjusting the duty cycle of the PWM signal, the equivalent energy of the output signal can be changed, thereby controlling the vibration amplitude of the passive buzzer and achieving volume gain adjustment. In some embodiments, the volume gain can also be achieved by adjusting the output power of the drive circuit.

[0042] To simulate the harmonic structure in a real engine sound, the PWM waveform generation unit can also superimpose digitally synthesized higher-order harmonic components, such as the second and third harmonics. These harmonic components are achieved by inserting a preset proportion of pulse sequences within the fundamental frequency PWM signal period, focusing on enhancing the energy distribution in the mid-to-low frequency range to improve the roaring characteristics similar to a V6 or V8 engine. The harmonic superposition parameters can be set according to different engine types.

[0043] Preferably, the sound wave control parameters further include harmonic control parameters; the PWM waveform generation unit is used to perform harmonic superposition processing on the fundamental frequency PWM signal based on the harmonic control parameters, generate a synthetic PWM drive signal containing at least one higher harmonic component, and output the synthetic PWM drive signal to the passive buzzer.

[0044] Specifically, the processing control unit further includes a mode management module; the mode management module is used to perform switching operations between preset operating modes, and when switching modes, it calls the preset rule base and preset parameter set of the corresponding operating mode to update the control rules of the sound wave control parameter generation module, and applies the updated control rules to the sound wave control parameter generation process.

[0045] In this embodiment of the invention, the sound wave control parameters include not only sound wave frequency parameters and sound wave amplitude parameters, but also harmonic control parameters. These harmonic control parameters are used to limit the number, frequency ratio, and energy distribution weight of higher-order harmonics. After generating a fundamental frequency PWM signal, the PWM waveform generation unit performs harmonic superposition processing on the fundamental frequency PWM signal according to the harmonic control parameters, forming a synthesized PWM drive signal containing at least one higher-order harmonic component. Specifically, the harmonic control parameters may include second-harmonic coefficients, third-harmonic coefficients, and corresponding amplitude scaling factors. The PWM waveform generation unit achieves synthetic control of higher-order harmonics by inserting sub-pulse sequences that are integer multiples of the fundamental frequency within one fundamental frequency cycle.

[0046] For example, when the fundamental frequency is 200Hz, 400Hz and 600Hz components can be superimposed, and their duty cycle ratio can be set according to the harmonic control parameters to enhance the energy in the mid-low frequency range and make the output sound more substantial. The synthesized PWM drive signal is directly output to the passive buzzer, thereby driving it to vibrate and produce sound at the composite frequency.

[0047] In this embodiment, the processing control unit further includes a mode management module. The mode management module is used to perform switching operations between preset operating modes. The preset operating modes may include a sports mode, a comfort mode, and a silent mode. Each operating mode corresponds to an independent preset rule base and preset parameter set. The preset rule base includes fuzzy logic control rules and resonance anchor point set parameters, and the preset parameter set includes control quantities such as harmonic control parameters, duty cycle adjustment coefficients, and continuity thresholds.

[0048] When the mode management module receives a mode switching command, it calls the preset rule base and preset parameter set of the corresponding operating mode, updates the control rules of the sound control parameter generation module, and applies the updated control rules to the subsequent sound control parameter generation process. In this way, in Sport mode, the proportion of higher harmonics can be increased and the amplitude anchor point value can be raised, making the sound performance more aggressive; in Comfort mode, the proportion of harmonics can be reduced and the frequency change rate can be limited, making the sound performance more stable; in Quiet mode, the sound amplitude parameter can be limited to a preset lower range. The mode switching process does not change the signal acquisition path, only updates the control rules and parameter set, thereby ensuring the continuity of system operation. The specific numerical settings of the above mode management mechanism and harmonic control parameters can be configured according to the vehicle model and application scenario, which are equivalent variations within the scope of protection of this invention.

[0049] In another possible implementation, a vehicle speed signal acquisition interface is added to the signal acquisition unit, and the vehicle speed signal, along with the engine speed signal and throttle opening signal, is input to the processing control unit. The sound wave control parameter generation module adds a correction factor based on the vehicle speed range when generating sound wave frequency and amplitude parameters.

[0050] In the low-speed range, the upper limit of the sound wave amplitude parameter is limited, and the higher harmonic control parameters are weakened to avoid excessively strong sound waves during low-speed driving or congested road conditions. In the medium-to-high-speed range, the sound wave amplitude parameter is allowed to amplify with changes in throttle opening, and the weight of low-to-mid-frequency frequencies in the harmonic control parameters is appropriately increased to enhance the expression of power during driving. The vehicle speed correction factor can participate in the calculation process of the sound wave frequency parameter and the sound wave amplitude parameter through a preset proportional coefficient, and participate in the rate of change constraint judgment within a continuous sampling period.

[0051] In another possible implementation, an environmental noise acquisition interface is added to the signal acquisition unit to acquire environmental noise intensity signals from outside or inside the vehicle. The environmental noise signal is input to the processing and control unit and participates in the correction process of the sound wave control parameters.

[0052] In the sound wave control parameter generation module, a noise compensation coefficient is set based on the ambient noise signal. When the ambient noise intensity is in a high range, the sound wave amplitude parameter is proportionally amplified to maintain the sound wave intensity perceptible to the driver; when the ambient noise intensity is in a low range, the sound wave amplitude parameter is limited to prevent excessive sound wave from affecting ride comfort. The noise compensation coefficient can be mapped to the ambient noise signal through a preset functional relationship and participates in the rate of change constraint judgment within a continuous sampling period. In addition, the noise compensation mechanism can also be linked with harmonic control parameters to enhance the mid-frequency energy distribution in high-noise environments, thereby improving the penetration of the sound wave. Through this additional implementation method, the sound wave output maintains a relatively stable subjective perception effect under different road conditions and driving environments.

[0053] Figure 2 This is a flowchart illustrating the steps of a dynamic engine sound simulation method according to one embodiment of the present invention. Figure 2 As shown, an embodiment of the present invention provides a method for simulating dynamic engine sound, the method comprising: Step S10: Acquire engine speed signal and throttle opening signal, and perform normalization processing on the engine speed signal and the throttle opening signal to generate normalized engine speed signal and normalized throttle opening signal; Step S20: Based on the normalized engine speed signal and the normalized throttle opening signal, perform sound control parameter generation calculation to generate sound control parameters including sound frequency parameters and sound amplitude parameters; Step S30: Generate a base frequency PWM signal based on the sound wave frequency parameters, and perform duty cycle modulation on the base frequency PWM signal based on the sound wave amplitude parameters to generate a PWM drive signal; Step S40: Output the PWM drive signal to the passive buzzer to output the corresponding engine sound simulation sound based on the PWM drive signal.

[0054] Preferably, a sound wave control parameter generation operation is performed based on the normalized engine speed signal and the normalized throttle opening signal to generate sound wave control parameters including sound wave frequency parameters and sound wave amplitude parameters. This includes: calculating the throttle opening change based on the throttle opening signal at continuously sampled times, and mapping the normalized engine speed signal, the normalized throttle opening signal, and the throttle opening change to a preset fuzzy linguistic variable set; performing fuzzy inference and defuzzification operations based on a preset rule base to generate the sound wave control parameters characterizing the sound wave frequency parameters and sound wave amplitude parameters; establishing a set of resonance anchor points corresponding to engine speed zones in the preset rule base, where each set of resonance anchor points corresponds to at least one preset speed zone and a target sound wave fundamental frequency anchor point value and a target sound wave amplitude anchor point value corresponding to the preset speed zone; after generating the sound wave control parameters... The sound wave frequency parameter and sound wave amplitude parameter are obtained from the sound wave control parameters, and the corresponding resonance anchor point set is called according to the preset speed range to which the current engine speed belongs; the sound wave frequency parameter is matched with the target sound wave fundamental frequency anchor point value to calculate the frequency offset, and constraint correction is performed based on the frequency offset to generate the corrected sound wave frequency parameter; the sound wave amplitude parameter is matched with the target sound wave amplitude anchor point value to calculate the amplitude offset, and constraint correction is performed based on the amplitude offset to generate the corrected sound wave amplitude parameter; the rate of change of the corrected sound wave frequency parameter and the corrected sound wave amplitude parameter are calculated respectively within a continuous sampling period, and envelope smoothing is performed respectively when the corresponding rate of change exceeds a preset continuity threshold to generate the final sound wave frequency parameter and the final sound wave amplitude parameter; the final sound wave frequency parameter and the final sound wave amplitude parameter are updated to the sound wave control parameters.

[0055] The present invention also provides a computer-readable storage medium storing instructions that, when executed on a computer, cause the computer to perform the above-described dynamic engine sound simulation method.

[0056] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program is stored in a storage medium and includes several instructions to cause a microcontroller, chip, or processor to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0057] The optional embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details described above. Within the scope of the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical solutions of the embodiments of the present invention, and these simple modifications all fall within the protection scope of the embodiments of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not further describe the various possible combinations.

[0058] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the embodiments of the present invention, they should also be regarded as the content disclosed by the embodiments of the present invention.

Claims

1. A dynamic engine sound simulation system, characterized in that, The system includes: The signal acquisition unit is used to acquire engine speed signals and throttle opening signals; The processing and control unit is connected to the signal acquisition unit and is used to generate sound control parameters based on the engine speed signal and the throttle opening signal. A PWM waveform generation unit is connected to the processing and control unit and is used to generate a corresponding PWM drive signal based on the sound wave control parameters. A passive buzzer, electrically connected to the PWM waveform generation unit, is used to output a simulated engine sound based on the PWM drive signal.

2. The dynamic engine sound simulation system according to claim 1, characterized in that, The processing control unit includes a signal preprocessing module, which performs normalization processing on the engine speed signal and the throttle opening signal, and calculates the throttle opening change based on the throttle opening signal at continuous sampling time. The signal preprocessing module outputs the normalized engine speed signal, the normalized throttle opening signal, and the throttle opening change to the sound control parameter generation module in the processing control unit.

3. The dynamic engine sound simulation system according to claim 2, characterized in that, The sound wave control parameter generation module is a fuzzy logic control module; The fuzzy logic control module is used to map the normalized engine speed signal and the normalized throttle opening signal to a preset set of fuzzy linguistic variables, respectively. Based on a preset rule base, fuzzy inference and defuzzification operations are performed to generate the sound wave control parameters that characterize the sound wave frequency and amplitude parameters, and the sound wave control parameters are output to the PWM waveform generation unit.

4. The dynamic engine sound simulation system according to claim 3, characterized in that, When the sound wave control parameter generation module generates the sound wave control parameters characterizing the sound wave frequency and amplitude parameters by performing fuzzy inference and defuzzification operations based on a preset rule base, it is configured as follows: A set of resonance anchor points corresponding to engine speed zones is established in a preset rule base. Each set of resonance anchor points corresponds to at least one preset speed zone and a target sound wave fundamental frequency anchor point value and a target sound wave amplitude anchor point value corresponding to the preset speed zone. After generating the sound wave control parameters, the sound wave frequency parameters and sound wave amplitude parameters are obtained from the sound wave control parameters, and the corresponding set of resonance anchor points is called according to the preset speed range to which the current engine speed belongs. The sound wave frequency parameters are matched with the target sound wave fundamental frequency anchor point value to calculate the frequency offset, and constraint correction is performed based on the frequency offset to generate corrected sound wave frequency parameters. The amplitude parameter of the sound wave is matched with the target amplitude anchor point value to calculate the amplitude offset, and the constraint correction is performed based on the amplitude offset to generate the corrected amplitude parameter of the sound wave. The rate of change of the corrected sound wave frequency parameter and the corrected sound wave amplitude parameter are calculated respectively within the continuous sampling period. When the corresponding rate of change exceeds the preset continuity threshold, envelope smoothing is performed to generate the final sound wave frequency parameter and the final sound wave amplitude parameter. Update the final sound wave frequency parameter and the final sound wave amplitude parameter to the sound wave control parameter.

5. The dynamic engine sound simulation system according to claim 3, characterized in that, The PWM waveform generation unit is used to generate a base frequency PWM signal based on the sound wave frequency parameter, and modulate the duty cycle of the base frequency PWM signal based on the sound wave amplitude parameter to generate a PWM drive signal for driving the passive buzzer, and output the PWM drive signal to the passive buzzer.

6. The dynamic engine sound simulation system according to claim 5, characterized in that, The sound wave control parameters also include harmonic control parameters; The PWM waveform generation unit is used to perform harmonic superposition processing on the fundamental frequency PWM signal based on the harmonic control parameters, generate a synthetic PWM drive signal containing at least one higher harmonic component, and output the synthetic PWM drive signal to the passive buzzer.

7. The dynamic engine sound simulation system according to claim 1, characterized in that, The processing control unit also includes a mode management module; The mode management module is used to perform switching operations between preset operating modes, and when switching modes, it calls the preset rule base and preset parameter set of the corresponding operating mode to update the control rules of the sound wave control parameter generation module, and applies the updated control rules to the sound wave control parameter generation process.

8. A method for simulating dynamic engine sound, characterized in that, The method is implemented based on the dynamic engine sound simulation system according to any one of claims 1-7, and the method includes: The engine speed signal and throttle opening signal are acquired, and the engine speed signal and throttle opening signal are normalized to generate normalized engine speed signal and normalized throttle opening signal. Based on the normalized engine speed signal and the normalized throttle opening signal, a sound control parameter generation calculation is performed to generate sound control parameters including sound frequency parameters and sound amplitude parameters. A base frequency PWM signal is generated based on the sound wave frequency parameters, and the duty cycle of the base frequency PWM signal is modulated based on the sound wave amplitude parameters to generate a PWM drive signal. The PWM drive signal is output to a passive buzzer to simulate engine sound based on the PWM drive signal.

9. The dynamic engine sound simulation method according to claim 8, characterized in that, Based on the normalized engine speed signal and the normalized throttle opening signal, a sound control parameter generation calculation is performed to generate sound control parameters including sound frequency parameters and sound amplitude parameters, including: The throttle opening change is calculated based on the throttle opening signal at continuous sampling time, and the normalized engine speed signal, the normalized throttle opening signal, and the throttle opening change are mapped to a preset fuzzy linguistic variable set. Based on a preset rule base, fuzzy inference and defuzzification operations are performed to generate the sound wave control parameters used to characterize the sound wave frequency parameters and sound wave amplitude parameters. A set of resonance anchor points corresponding to engine speed zones is established in the preset rule base. Each set of resonance anchor points corresponds to at least one preset speed zone and a target sound wave fundamental frequency anchor point value and a target sound wave amplitude anchor point value corresponding to the preset speed zone. After generating the sound wave control parameters, the sound wave frequency parameters and sound wave amplitude parameters are obtained from the sound wave control parameters, and the corresponding set of resonance anchor points is called according to the preset speed range to which the current engine speed belongs. The sound wave frequency parameter is matched with the target sound wave fundamental frequency anchor value to calculate the frequency offset, and constraint correction is performed based on the frequency offset to generate the corrected sound wave frequency parameter; the sound wave amplitude parameter is matched with the target sound wave amplitude anchor value to calculate the amplitude offset, and constraint correction is performed based on the amplitude offset to generate the corrected sound wave amplitude parameter. The rate of change of the corrected sound wave frequency parameter and the corrected sound wave amplitude parameter are calculated respectively within the continuous sampling period, and envelope smoothing is performed respectively when the corresponding rate of change exceeds the preset continuity threshold to generate the final sound wave frequency parameter and the final sound wave amplitude parameter. Update the final sound wave frequency parameter and the final sound wave amplitude parameter to the sound wave control parameter.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores instructions that, when executed on a computer, cause the computer to perform the dynamic engine sound simulation method as described in any one of claims 8 and 9.

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