A control method and device for a semi-active suspension based on road recognition

Abstract

The application discloses a control method and device of a semi-active suspension based on road surface identification, comprising: periodically acquiring a current acceleration signal collected by a sensor, and calculating a current frequency band characteristic parameter of a vehicle according to the current acceleration signal; determining the sum of all high-frequency signals in a sampling period according to the current frequency band characteristic parameter; judging whether the sum of all high-frequency signals is not less than a high-frequency threshold value; if the sum of all high-frequency signals is not less than the high-frequency threshold value, determining that the current body vibration state of the vehicle is a high-frequency vibration state, and recording the duration of the high-frequency vibration state; detecting whether the duration of the high-frequency vibration state recorded in real time satisfies a preset time threshold value; if the duration of the high-frequency vibration state recorded in real time satisfies the preset time threshold value, starting current compensation of the vehicle to control the semi-active suspension of the vehicle. Thus, the excitation form of the vehicle is identified through a road surface identification process, and then the current compensation is determined to control the semi-active suspension of the vehicle, so that the problem of high hardware cost is effectively reduced without the intervention of hardware.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle control, in particular to a control method and device of semi-active suspension based on road surface identification. BACKGROUND

[0002] The semi-active suspension can improve the comfort and handling of the vehicle by increasing the electronic control system on the basis of the passive suspension and adjusting the damping force according to the real-time road conditions and driving requirements. Therefore, when the road conditions change, how to make the control strategy quickly adapt to and meet the rapid changes of the vehicle dynamic performance is a key problem that must be overcome in the development of semi-active suspension.

[0003] In the existing technology, the off-line analysis method is mainly used, that is, the vertical acceleration signal at a certain position of the vehicle body is subjected to Fourier transform to obtain the power spectral density, so as to determine the main frequency influence on the vehicle body, and then the semi-active suspension is controlled according to the frequency influence.

[0004] However, the Fourier transform is difficult to guarantee in real-time, and the computing power requirement of the controller is high, thereby increasing the control cost of the chip with the Fourier transform processing process. SUMMARY

[0005] Based on the above-mentioned deficiencies of the prior art, the present application provides a control method and device of semi-active suspension based on road surface identification to solve the problem of increasing hardware cost caused by the prior art.

[0006] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0007] The first aspect of the present application provides a control method of semi-active suspension based on road surface identification, comprising:

[0008] Periodically acquiring a current acceleration signal collected by a sensor, and calculating a current frequency band characteristic parameter of the vehicle according to the current acceleration signal;

[0009] According to the current frequency band characteristic parameter, determining the sum of all high frequency signals in a sampling period; wherein the sampling period is created in advance according to the frequency of the sensor sampling; the high frequency signal refers to a frequency band characteristic parameter greater than a preset threshold value;

[0010] Judging whether the sum of all the high frequency signals is not less than a high frequency threshold value;

[0011] If the sum of all the high frequency signals is not less than the high frequency threshold value, it is determined that the current body vibration state of the vehicle is a high frequency vibration state, and the duration of the high frequency vibration state is recorded;

[0012] Real-time detection and recording of whether the duration of the high-frequency vibration state meets a preset time threshold;

[0013] If the recorded duration of the high-frequency vibration state meets a preset time threshold, current compensation of the vehicle is started to control the semi-active suspension of the vehicle.

[0014] Optionally, in the above-mentioned method for controlling a semi-active suspension based on road surface recognition, calculating the current frequency band characteristic parameters of the vehicle according to the current acceleration signal includes:

[0015] Obtaining a vehicle body vertical acceleration signal measured by a measuring unit;

[0016] Integrating the current acceleration signal to obtain a vertical acceleration signal of the target vehicle body;

[0017] Based on the vehicle body vertical acceleration signal, the target vehicle body vertical acceleration signal and a preset frequency limit, a current frequency band characteristic parameter of the vehicle is calculated.

[0018] Optionally, in the above-mentioned semi-active suspension control method based on road surface recognition, determining the sum of all high-frequency signals within a sampling period according to the current frequency band characteristic parameter includes:

[0019] Obtain characteristic parameters of all frequency bands within the sampling period;

[0020] Deleting the first frequency band characteristic parameter in the sampling period, and adding the current frequency band characteristic parameter to the last frequency band characteristic parameter in the sampling period to obtain a new sampling period;

[0021] Extracting all frequency band characteristic parameters greater than a preset threshold from the new sampling period, and treating all frequency band characteristic parameters greater than the preset threshold as high-frequency signals;

[0022] The sum of all the high-frequency signals is calculated to obtain a target value, and the target value is determined as the sum of all the high-frequency signals in a sampling period.

[0023] Optionally, in the above-mentioned semi-active suspension control method based on road surface recognition, after determining whether the sum of all the high-frequency signals is not less than the high-frequency threshold, the method further includes:

[0024] If the sum of all the high-frequency signals is less than the high-frequency threshold, it is determined that the current body vibration state of the vehicle is a low-frequency vibration state.

[0025] Optionally, in the above-mentioned method for controlling a semi-active suspension based on road surface recognition, the method further includes:

[0026] When it is detected that the current body vibration state of the vehicle is a low-frequency vibration state while recording the duration of the high-frequency vibration state, the duration of the high-frequency vibration state is cleared.

[0027] Optionally, in the above-mentioned method for controlling a semi-active suspension based on road surface recognition, after starting the current compensation of the vehicle to control the semi-active suspension of the vehicle, the method further includes:

[0028] When it is detected that the current body vibration state of the vehicle is a low-frequency vibration state, recording the duration of the low-frequency vibration state;

[0029] Real-time detection and recording of whether the duration of the low-frequency vibration state meets a preset time threshold;

[0030] If the recorded duration of the low-frequency vibration state meets a preset time threshold, shutting down the current compensation of the vehicle;

[0031] If the duration of recording the low-frequency vibration state does not meet the preset time threshold, the process returns to executing the duration of recording the low-frequency vibration state.

[0032] Optionally, in the above-mentioned semi-active suspension control method based on road surface recognition, the method further includes:

[0033] When it is detected that the current body vibration state of the vehicle is a high-frequency vibration state during the recording of the duration of the low-frequency vibration state, and the duration of the high-frequency vibration state meets the preset time threshold, the current compensation of the vehicle is started.

[0034] A second aspect of the present application provides a control device for a semi-active suspension based on road surface recognition, comprising:

[0035] A parameter calculation unit, configured to periodically obtain a current acceleration signal collected by the sensor and calculate characteristic parameters of a current frequency band of the vehicle based on the current acceleration signal;

[0036] a sum determination unit, configured to determine the sum of all high-frequency signals within a sampling period based on the current frequency band characteristic parameter; wherein the sampling period is pre-established based on the sampling frequency of the sensor; and the high-frequency signal refers to a frequency band characteristic parameter greater than a preset threshold;

[0037] a threshold judgment unit, configured to judge whether the sum of all the high-frequency signals is not less than a high-frequency threshold;

[0038] a time recording unit, configured to determine that the current body vibration state of the vehicle is a high-frequency vibration state if the sum of all the high-frequency signals is not less than a high-frequency threshold, and record the duration of the high-frequency vibration state;

[0039] a time detection unit, configured to detect in real time whether the duration of the high-frequency vibration state meets a preset time threshold;

[0040] The current starting unit is used to start the current compensation of the vehicle if the duration of the high-frequency vibration state recorded meets a preset time threshold, so as to control the semi-active suspension of the vehicle.

[0041] Optionally, in the above-mentioned semi-active suspension control device based on road surface recognition, the parameter calculation unit includes:

[0042] A signal acquisition unit, used to acquire the vehicle body vertical acceleration signal measured by the measurement unit;

[0043] an integral processing unit, configured to perform integral processing on the current acceleration signal to obtain a vertical acceleration signal of the target vehicle body;

[0044] The parameter calculation subunit is used to calculate the current frequency band characteristic parameters of the vehicle based on the vehicle body vertical acceleration signal, the target vehicle body vertical acceleration signal and a preset frequency limit.

[0045] Optionally, in the above-mentioned control device for semi-active suspension based on road surface recognition, the sum determination unit includes:

[0046] A parameter acquisition unit, used to obtain characteristic parameters of all frequency bands within a sampling period;

[0047] a deleting unit, configured to delete the first frequency band characteristic parameter in the sampling period and add the current frequency band characteristic parameter to the last frequency band characteristic parameter in the sampling period to obtain a new sampling period;

[0048] an extraction unit, configured to extract all frequency band characteristic parameters greater than a preset threshold from the new sampling period, and use all frequency band characteristic parameters greater than the preset threshold as high-frequency signals;

[0049] The summation sub-determination unit is configured to calculate the sum of all the high-frequency signals to obtain a target value, and determine the target value as the sum of all the high-frequency signals within a sampling period.

[0050] Optionally, the above-mentioned semi-active suspension control device based on road surface recognition further includes:

[0051] The determining unit is configured to determine that the current body vibration state of the vehicle is a low-frequency vibration state if the sum of all the high-frequency signals is less than a high-frequency threshold.

[0052] Optionally, the above-mentioned semi-active suspension control device based on road surface recognition further includes:

[0053] The zero clearing processing unit is used to clear the duration of the high-frequency vibration state when it is detected that the current body vibration state of the vehicle is a low-frequency vibration state during the recording of the duration of the high-frequency vibration state.

[0054] Optionally, the above-mentioned semi-active suspension control device based on road surface recognition further includes:

[0055] a recording unit, configured to, when detecting that the current body vibration state of the vehicle is a low-frequency vibration state, record the duration of the low-frequency vibration state;

[0056] A detection unit, configured to detect and record in real time whether the duration of the low-frequency vibration state meets a preset time threshold;

[0057] a shut-down unit, configured to shut down the current compensation of the vehicle if the duration of the low-frequency vibration state recorded satisfies a preset time threshold;

[0058] The execution unit is configured to return to executing the step of recording the duration of the low-frequency vibration state if the duration of the low-frequency vibration state does not meet a preset time threshold.

[0059] Optionally, the above-mentioned semi-active suspension control device based on road surface recognition further includes:

[0060] The activation unit is configured to activate the current compensation of the vehicle when, while recording the duration of the low-frequency vibration state, it is detected that the current body vibration state of the vehicle is a high-frequency vibration state, and the duration of the high-frequency vibration state recorded meets the preset time threshold.

[0061] This application provides a control method for a semi-active suspension based on road surface recognition. The method periodically acquires a current acceleration signal collected by a sensor and calculates the vehicle's current frequency band characteristic parameters based on the current acceleration signal. The method then determines the sum of all high-frequency signals within a sampling period based on the current frequency band characteristic parameters. The sampling period is pre-established based on the sensor sampling frequency, and a high-frequency signal refers to a frequency band characteristic parameter greater than a preset threshold. The method then determines whether the sum of all high-frequency signals is no less than the high-frequency threshold. If the sum of all high-frequency signals is no less than the high-frequency threshold, the vehicle's current body vibration state is determined to be a high-frequency vibration state, and the duration of the high-frequency vibration state is recorded. Finally, the method detects in real time whether the duration of the recorded high-frequency vibration state meets a preset time threshold. If the duration of the recorded high-frequency vibration state meets the preset time threshold, current compensation is activated to control the vehicle's semi-active suspension. The method thus identifies the vehicle's excitation form through the road surface recognition process, and then determines current compensation to control the vehicle's semi-active suspension. This eliminates the need for hardware intervention and effectively reduces hardware costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.

[0063] Figure 1 A schematic structural diagram of a control device provided in an embodiment of the present application;

[0064] Figure 2 A schematic flow chart of a control method for a semi-active suspension based on road surface recognition provided in an embodiment of the present application;

[0065] Figure 3 A flowchart of a method for calculating frequency band characteristic parameters provided in another embodiment of the present application;

[0066] Figure 4 A flowchart of a method for determining the sum of high-frequency signals provided in another embodiment of the present application;

[0067] Figure 5 A schematic flow chart of a method for handling a vehicle in a low-frequency vibration state provided by another embodiment of the present application;

[0068] Figure 6 A schematic diagram of the interface structure of a control method for a semi-active suspension based on road surface recognition provided in an embodiment of the present application;

[0069] Figure 7 A schematic structural diagram of a control device for a semi-active suspension based on road surface recognition provided in another embodiment of the present application. DETAILED DESCRIPTION

[0070] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0071] In this application, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus comprising the element.

[0072] An embodiment of the present application provides a control method for a semi-active suspension based on road surface recognition, which is applied to a control device to solve the problem of increased hardware cost brought about by the prior art.

[0073] Alternatively, as Figure 1 As shown, an embodiment of the present application provides a control device, including: a frequency band calculation module, a sliding time window module and a current compensation module.

[0074] It should be noted that the frequency band calculation module is mainly used to identify the quality of the driving road and output the frequency band characteristic parameters to the sliding time window module.

[0075] The sliding time window module is used to extract the high-frequency characteristic parameters encountered by the vehicle when driving on the road based on the frequency band characteristic parameters, and pass the sum of the high-frequency characteristic parameters within a certain time window to the current compensation module.

[0076] The current compensation module determines whether to trigger current compensation based on the duration of the high-frequency signal, and can calibrate different compensation currents in combination with the suspension damper mode to improve the adaptability of the suspension.

[0077] Based on the control device provided above, the embodiment of the present application provides a control method for a semi-active suspension based on road surface recognition, such as Figure 2 As shown, the specific steps include:

[0078] S201 , periodically acquiring a current acceleration signal collected by a sensor, and calculating a current frequency band characteristic parameter of the vehicle based on the current acceleration signal.

[0079] Specifically, in order to control the semi-active suspension on bumpy roads to improve user comfort, in an embodiment of the present application, the frequency band characteristic parameters of the vehicle output are used to determine whether the vehicle outputs low-frequency excitation or high-frequency excitation, thereby controlling the semi-active suspension. Therefore, according to development experience, the excitation received by the vehicle when driving on a good road is mainly low-frequency, so there is no need to control the semi-active suspension. When the road conditions are bumpy, the excitation form received by the vehicle is mainly high-frequency, then the semi-active suspension needs to be turned on to work. Therefore, the vehicle's acceleration signal can be collected to determine the vehicle's frequency band characteristic parameters, and then the frequency band characteristic parameters can be used to characterize whether the current road environment's impact on the vehicle body vibration is high-frequency excitation or low-frequency excitation.

[0080] Optionally, in another embodiment of the present application, a specific implementation method of calculating the current frequency band characteristic parameters of the vehicle according to the current acceleration signal in step S201 is as follows: Figure 3 As shown, the following steps are included:

[0081] S301: Acquire a vehicle body vertical acceleration signal measured by a measurement unit.

[0082] Specifically, an inertial measurement unit (IMU) mounted at the vehicle's center of mass can directly measure the vehicle's vertical acceleration signal during driving. This vertical acceleration signal refers to the vehicle's acceleration in the vertical direction relative to the ground (usually the depth direction). It is typically related to the vehicle's vertical vibration, pitch, and vibration frequency.

[0083] S302: Integrate the current acceleration signal to obtain a vertical acceleration signal of the target vehicle body.

[0084] It is understandable that a numerical integration method may be used to perform integration processing on the current acceleration signal, thereby obtaining the vehicle body vertical motion velocity information, that is, the target vehicle body vertical acceleration signal.

[0085] Optionally, the numerical integration may be Euler integration method, trapezoidal rule, Runge-Kutta method, etc.

[0086] S303 : Calculate characteristic parameters of the current frequency band of the vehicle based on the vehicle body vertical acceleration signal, the target vehicle body vertical acceleration signal, and the preset frequency limit.

[0087] Specifically, the calculation formula for the characteristic parameters of the current frequency band is:

[0088]

[0089] in, is the vehicle body vertical acceleration signal, is the target vehicle body vertical acceleration signal, a is the preset frequency limit between high frequency and low frequency. In suspension control, the value of a should be set at the damping fixed point, about 3.2 Hz.

[0090] S202: Determine the sum of all high-frequency signals within a sampling period according to characteristic parameters of the current frequency band.

[0091] The sampling period is pre-established based on the sampling frequency of the sensor. High-frequency signals refer to frequency band characteristic parameters that are greater than a preset threshold.

[0092] Specifically, a time window of a certain length can be established according to the time when the sensor collects signals, that is, the sampling period, and then the frequency band characteristic parameter F calculated for each sampling is recorded. When the sampling period is full of frequency band characteristic parameters F, the sum of all high-frequency signals in the sampling period is counted, that is, the frequency band characteristic parameters F of all frequency bands in the sampling period that are greater than the preset threshold are regarded as high-frequency signals.

[0093] Optionally, in another embodiment of the present application, a specific implementation of step S202 is as follows: Figure 4 As shown, the following steps are included:

[0094] S401: Acquire characteristic parameters of all frequency bands within a sampling period.

[0095] S402: Delete the first frequency band characteristic parameter in the sampling period, and add the current frequency band characteristic parameter to the last position in the sampling period to obtain a new sampling period.

[0096] It should be noted that when the sampling period is full of frequency band characteristic parameters, when new frequency band characteristic parameters are received, it is necessary to delete the first frequency band characteristic parameter in the sampling period and place the newly received frequency band characteristic parameter at the end of the sampling period, thereby forming a new sampling period to represent the excitation received by the current vehicle, and also to achieve the effect of sliding recording of real-time signals.

[0097] For example, assuming the sampling period window is 10, the frequency band selector begins calculating the characteristic parameter F from the moment the vehicle is powered on, running every 2ms. Each calculated result is stored in the sampling period. During the sampling period, the number of characteristic parameters F greater than 0 within the window is counted and the specific number is output. Otherwise, the result is 0. After 10 periods, the statistical time window is full of characteristic parameters F. When a new characteristic parameter F is stored in the 11th period, the characteristic parameter F calculated in the first position of the time window (i.e., the first period) is deleted, and the characteristic parameter F result of the 11th period is stored in the last position of the window (i.e., the characteristic parameters F of periods 2 to 11 are retained in the window).

[0098] S403 : extracting all frequency band characteristic parameters greater than a preset threshold from the new sampling period, and taking all frequency band characteristic parameters greater than the preset threshold as high-frequency signals.

[0099] It should be noted that when the vehicle outputs a high-frequency signal, it means that the vehicle needs to activate the semi-active suspension. Therefore, in the embodiment of the present application, the frequency band characteristic parameter F greater than 0 is used as the high-frequency band characteristic signal, otherwise it is a low-frequency band characteristic signal. Therefore, it is necessary to extract all frequency band characteristic parameters greater than the preset threshold from the new sampling period, that is, to characterize the number of signals that the vehicle body is affected by the high-frequency band under the current driving environment.

[0100] S404 , calculating the sum of all high-frequency signals to obtain a target value, and determining the target value as the sum of all high-frequency signals within a sampling period.

[0101] Specifically, the sum of all high-frequency signals is calculated and transmitted to the current compensation module, so that the circuit compensation module determines whether to turn on the current based on the sum of the high-frequency signals.

[0102] S203: Determine whether the sum of all high-frequency signals is not less than a high-frequency threshold.

[0103] It should be noted that in order to further determine whether the road excitation currently applied to the vehicle is a high excitation, a decision can be made based on the vehicle body vibration state. Specifically, the expression for determining the vehicle body vibration state is:

[0104]

[0105] Among them, V b Indicates the vehicle body vibration state, SUM F Represents the sum of high-frequency signals, Thres F Therefore, if the sum of all high-frequency signals is not less than the high-frequency threshold, the vehicle body vibration state is 1, which represents a high-frequency vibration state, and step S204 is executed.

[0106] Optionally, after executing step S203, the method further includes:

[0107] If the sum of all high-frequency signals is less than the high-frequency threshold, it is determined that the current body vibration state of the vehicle is a low-frequency vibration state.

[0108] It is understandable that if the sum of all high-frequency signals is less than the high-frequency threshold, the vehicle body vibration state is 0, which represents a low-frequency vibration state, indicating that the current road conditions are good and there is no need for semi-active suspension intervention to enhance the user experience.

[0109] S204: Determine whether the current body vibration state of the vehicle is a high-frequency vibration state, and record the duration of the high-frequency vibration state.

[0110] It can be understood that when the sum of all high-frequency signals is not less than the high-frequency threshold, it means that the current body vibration state of the vehicle is a high-frequency vibration state, and semi-active suspension intervention may be required. In order to improve the performance stability and comfort of the vehicle or equipment and extend its service life, it is also necessary to record the duration of the high-frequency vibration state.

[0111] Optionally, while recording the duration of the high-frequency vibration state of the vehicle, the vibration state of the vehicle may be in a low-frequency vibration state. In order to promptly handle the vehicle in the low-frequency vibration state to avoid accidents, in another embodiment of the present application, after executing step S204, the following further steps are further included:

[0112] When it is detected that the current body vibration state of the vehicle is a low-frequency vibration state while recording the duration of the high-frequency vibration state, the duration of the high-frequency vibration state is cleared.

[0113] It should be noted that if the vehicle's current vibration state is low-frequency while recording the duration of the high-frequency vibration state, it is necessary to set the duration of the high-frequency vibration state to 0 to avoid enabling current compensation. In addition, the duration should be recorded again the next time the vehicle's current vibration state is high-frequency.

[0114] S205 : Detect and record in real time whether the duration of the high-frequency vibration state meets a preset time threshold.

[0115] Specifically, if the duration of the recorded high-frequency vibration state does not meet the preset time threshold, current compensation is turned on, which may cause potential failures and performance degradation. Therefore, if the duration of the recorded high-frequency vibration state meets the preset time threshold, it means that circuit compensation can be turned on, so step S206 is executed.

[0116] Optionally, if the duration of the high-frequency vibration state is recorded to meet a preset time threshold, the duration of the high-frequency vibration state continues to be recorded.

[0117] S206 : Start the current compensation of the vehicle to control the semi-active suspension of the vehicle.

[0118] Specifically, when the duration of the recorded high-frequency vibration state meets a preset time threshold, the vehicle's current compensation can be turned on to control the vehicle's semi-active suspension, thereby improving user comfort.

[0119] For example, when the suspension is subjected to high-frequency excitation from the road, if the shock absorber can maintain a relatively soft damping state, it can better filter out the subtle vibrations of the road. Assuming the suspension is not currently in a relatively soft state, this type of current compensation can lower the operating current of the suspension shock absorber, keeping it in a relatively soft state and thus improving passenger comfort.

[0120] Optionally, after current compensation is turned on, the vehicle's vibration state may be in a low-frequency vibration state. In order to respond to the semi-active suspension in a timely manner, it is possible to avoid long-term high-frequency vibration that may cause excessive wear, fatigue, or resonance of components, ultimately affecting the stability and comfort of the system. Therefore, in another embodiment of the present application, after current compensation is turned on, the current body vibration state of the vehicle is also detected for subsequent processing. Optionally, as Figure 5 As shown, another embodiment of the present application provides a method for handling a vehicle in a low-frequency vibration state, comprising the following steps:

[0121] S501 : When it is detected that the current body vibration state of the vehicle is a low-frequency vibration state, the duration of the low-frequency vibration state is recorded.

[0122] It should be noted that during current compensation, if it is detected that the current body vibration state of the vehicle is a low-frequency vibration state, the circuit compensation module will not exit the current compensation immediately. It needs to wait until the duration of the low-frequency vibration state meets the preset time threshold before exiting. This can effectively avoid frequent compensation switching, reduce system oscillations, and avoid unstable states caused by premature exit from compensation, while improving energy efficiency and equipment life. Therefore, the timing starts at the moment when the current body vibration state of the vehicle is a low-frequency vibration state.

[0123] S502: Detect and record in real time whether the duration of the low-frequency vibration state meets a preset time threshold.

[0124] Specifically, if the duration of the low-frequency vibration state recorded meets the preset time threshold, it indicates that current compensation needs to be exited, and step S503 is executed. If the duration of the low-frequency vibration state recorded does not meet the preset time threshold, it indicates that current compensation cannot be exited yet, and the duration of the low-frequency vibration state needs to be further recorded until the duration of the low-frequency vibration state recorded meets the preset time threshold, and the process returns to step S501 to record the duration of the low-frequency vibration state.

[0125] S503: Turn off the current compensation of the vehicle.

[0126] It is understandable that when the duration of the recorded low-frequency vibration state meets the preset time threshold, the current compensation module needs to immediately shut down the vehicle's current compensation to avoid affecting the stability of the system.

[0127] Optionally, while recording the duration of the low-frequency vibration state of the vehicle, the vibration state of the vehicle may change back to a high-frequency vibration state. In order to promptly process the vehicle in the high-frequency vibration state and improve the user experience, in another embodiment of the present application, after executing step S501, the following further steps are further included:

[0128] When the current body vibration state of the vehicle is detected as a high-frequency vibration state during the duration of recording the low-frequency vibration state, and the duration of recording the high-frequency vibration state meets a preset time threshold, the current compensation of the vehicle is started.

[0129] It can be understood that when the current body vibration state of the vehicle is a high-frequency vibration state while recording the duration of the low-frequency vibration state, it is necessary to start recording the duration of the high-frequency vibration state. When the duration of the recorded high-frequency vibration state meets the preset time threshold, the current compensation continues.

[0130] It should be noted that the interface structure diagram of a control method of a semi-active suspension based on road surface recognition in an embodiment of the present application is as follows: Figure 6 As shown in the figure, the IMU (measurement unit) installed at the center of mass of the vehicle body can directly measure the vertical acceleration information of the vehicle body during driving. The on-board CAN bus can provide the mode information of the suspension shock absorber. After being processed by the built-in algorithm of the semi-active suspension controller, the control current signal is output to the corresponding actuator to complete the suspension control.

[0131] This application provides a control method for a semi-active suspension based on road surface recognition. The method periodically acquires a current acceleration signal collected by a sensor and calculates the vehicle's current frequency band characteristic parameters based on the current acceleration signal. The method then determines the sum of all high-frequency signals within a sampling period based on the current frequency band characteristic parameters. The sampling period is pre-established based on the sensor sampling frequency, and a high-frequency signal refers to a frequency band characteristic parameter greater than a preset threshold. The method then determines whether the sum of all high-frequency signals is no less than the high-frequency threshold. If the sum of all high-frequency signals is no less than the high-frequency threshold, the vehicle's current body vibration state is determined to be a high-frequency vibration state, and the duration of the high-frequency vibration state is recorded. Finally, the method detects in real time whether the duration of the recorded high-frequency vibration state meets a preset time threshold. If the duration of the recorded high-frequency vibration state meets the preset time threshold, current compensation is activated to control the vehicle's semi-active suspension. The method thus identifies the vehicle's excitation form through the road surface recognition process, and then determines current compensation to control the vehicle's semi-active suspension. This eliminates the need for hardware intervention and effectively reduces hardware costs.

[0132] Another embodiment of the present application provides a control device for a semi-active suspension based on road surface recognition, such as Figure 7 As shown, it includes the following units:

[0133] The parameter calculation unit 701 is used to periodically obtain the current acceleration signal collected by the sensor and calculate the current frequency band characteristic parameters of the vehicle based on the current acceleration signal.

[0134] The sum determination unit 702 is configured to determine the sum of all high-frequency signals within a sampling period based on the current frequency band characteristic parameter. The sampling period is pre-established based on the sensor sampling frequency. A high-frequency signal refers to a frequency band characteristic parameter greater than a preset threshold.

[0135] The threshold determination unit 703 is configured to determine whether the sum of all high-frequency signals is not less than a high-frequency threshold.

[0136] The time recording unit 704 is configured to determine that the current body vibration state of the vehicle is a high-frequency vibration state if the sum of all high-frequency signals is not less than the high-frequency threshold, and record the duration of the high-frequency vibration state.

[0137] The time detection unit 705 is used to detect in real time whether the duration of the high-frequency vibration state meets a preset time threshold.

[0138] The current starting unit 706 is configured to start the current compensation of the vehicle to control the semi-active suspension of the vehicle if the duration of the recorded high-frequency vibration state meets a preset time threshold.

[0139] It should be noted that the specific working process of the above-mentioned units in the embodiment of the present application can refer to steps S201 to S206 in the above-mentioned method embodiment, and will not be repeated here.

[0140] Optionally, in a control device for a semi-active suspension based on road surface recognition provided in another embodiment of the present application, the parameter calculation unit 701 includes:

[0141] The signal acquisition unit is used to acquire the vehicle body vertical acceleration signal measured by the measurement unit.

[0142] The integral processing unit is used to perform integral processing on the current acceleration signal to obtain the vertical acceleration signal of the target vehicle body.

[0143] The parameter calculation subunit is used to calculate the current frequency band characteristic parameters of the vehicle based on the vehicle body vertical acceleration signal, the target vehicle body vertical acceleration signal and the preset frequency limit.

[0144] Optionally, in a control device for a semi-active suspension based on road surface recognition provided in another embodiment of the present application, the sum determination unit 702 includes:

[0145] The parameter acquisition unit is used to obtain characteristic parameters of all frequency bands within a sampling period.

[0146] The deleting unit is used to delete the first frequency band characteristic parameter in the sampling period and add the current frequency band characteristic parameter to the last position in the sampling period to obtain a new sampling period.

[0147] The extraction unit is used to extract all frequency band characteristic parameters greater than a preset threshold from the new sampling period, and use all frequency band characteristic parameters greater than the preset threshold as high-frequency signals.

[0148] The summation sub-determination unit is used to calculate the sum of all high-frequency signals to obtain a target value, and determine the target value as the sum of all high-frequency signals within a sampling period.

[0149] Optionally, another embodiment of the present application provides a control device for a semi-active suspension based on road surface recognition, further comprising:

[0150] The determining unit is configured to determine that the current body vibration state of the vehicle is a low-frequency vibration state if the sum of all high-frequency signals is less than a high-frequency threshold.

[0151] Optionally, another embodiment of the present application provides a control device for a semi-active suspension based on road surface recognition, further comprising:

[0152] The zero clearing processing unit is used for clearing the duration of the high-frequency vibration state when it is detected that the current body vibration state of the vehicle is a low-frequency vibration state during the recording of the duration of the high-frequency vibration state.

[0153] Optionally, another embodiment of the present application provides a control device for a semi-active suspension based on road surface recognition, further comprising:

[0154] The recording unit is used to record the duration of the low-frequency vibration state when it is detected that the current body vibration state of the vehicle is a low-frequency vibration state.

[0155] The detection unit is used to detect in real time whether the duration of the low-frequency vibration state meets a preset time threshold.

[0156] The shut-down unit is configured to shut down the current compensation of the vehicle if the duration of the recorded low-frequency vibration state meets a preset time threshold.

[0157] The execution unit is configured to return to executing the recording of the duration of the low-frequency vibration state if the duration of the low-frequency vibration state does not meet a preset time threshold.

[0158] Optionally, another embodiment of the present application provides a control device for a semi-active suspension based on road surface recognition, further comprising:

[0159] The activation unit is used to activate the current compensation of the vehicle when it is detected that the current body vibration state of the vehicle is a high-frequency vibration state during the duration of recording the low-frequency vibration state, and the duration of recording the high-frequency vibration state meets a preset time threshold.

[0160] It should be noted that the specific working process of each unit provided in the above embodiments of the present application can refer to the corresponding steps in the above method embodiments, and will not be repeated here.

[0161] It should also be noted that the control device for a semi-active suspension based on road surface recognition provided in the embodiment of the present application has the technical effects of any of the above embodiments, and the embodiments of the present application are not described in detail here.

[0162] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0163] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present application. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A control method for a semi-active suspension based on road surface recognition, characterized in that: include: Periodically acquiring a current acceleration signal collected by a sensor, and calculating a current frequency band characteristic parameter of the vehicle based on the current acceleration signal; Determine the sum of all high-frequency signals within a sampling period based on the current frequency band characteristic parameter; wherein the sampling period is pre-established based on the sampling frequency of the sensor; and the high-frequency signal refers to a frequency band characteristic parameter greater than a preset threshold; Determining whether the sum of all the high-frequency signals is not less than a high-frequency threshold; If the sum of all the high-frequency signals is not less than the high-frequency threshold, determining that the current body vibration state of the vehicle is a high-frequency vibration state, and recording the duration of the high-frequency vibration state; Real-time detection and recording of whether the duration of the high-frequency vibration state meets a preset time threshold; If the recorded duration of the high-frequency vibration state meets a preset time threshold, current compensation of the vehicle is started to control the semi-active suspension of the vehicle.

2. The method according to claim 1, characterized in that Calculating the current frequency band characteristic parameters of the vehicle according to the current acceleration signal includes: Obtaining a vehicle body vertical acceleration signal measured by a measuring unit; Integrating the current acceleration signal to obtain a vertical acceleration signal of the target vehicle body; Based on the vehicle body vertical acceleration signal, the target vehicle body vertical acceleration signal and a preset frequency limit, a current frequency band characteristic parameter of the vehicle is calculated.

3. The method according to claim 1, characterized in that The determining the sum of all high-frequency signals within a sampling period according to the characteristic parameters of the current frequency band includes: Obtain characteristic parameters of all frequency bands within the sampling period; Deleting the first frequency band characteristic parameter in the sampling period, and adding the current frequency band characteristic parameter to the last frequency band characteristic parameter in the sampling period to obtain a new sampling period; Extracting all frequency band characteristic parameters greater than a preset threshold from the new sampling period, and treating all frequency band characteristic parameters greater than the preset threshold as high-frequency signals; The sum of all the high-frequency signals is calculated to obtain a target value, and the target value is determined as the sum of all the high-frequency signals within a sampling period.

4. The method according to claim 1, wherein After determining whether the sum of all the high-frequency signals is not less than the high-frequency threshold, the method further includes: If the sum of all the high-frequency signals is less than the high-frequency threshold, it is determined that the current body vibration state of the vehicle is a low-frequency vibration state.

5. The method according to claim 1, wherein Also includes: When it is detected that the current body vibration state of the vehicle is a low-frequency vibration state while recording the duration of the high-frequency vibration state, the duration of the high-frequency vibration state is cleared.

6. The method according to any one of claims 1 to 4, characterized in that After starting the current compensation of the vehicle to control the semi-active suspension of the vehicle, the method further includes: When it is detected that the current body vibration state of the vehicle is a low-frequency vibration state, recording the duration of the low-frequency vibration state; Real-time detection and recording of whether the duration of the low-frequency vibration state meets a preset time threshold; If the recorded duration of the low-frequency vibration state meets a preset time threshold, shutting down the current compensation of the vehicle; If the duration of recording the low-frequency vibration state does not meet the preset time threshold, the process returns to executing the duration of recording the low-frequency vibration state.

7. The method according to claim 6, characterized in that Also includes: When it is detected that the current body vibration state of the vehicle is a high-frequency vibration state during the recording of the duration of the low-frequency vibration state, and the duration of the high-frequency vibration state meets the preset time threshold, the current compensation of the vehicle is started.

8. A control device for a semi-active suspension based on road surface recognition, characterized in that: include: A parameter calculation unit, configured to periodically obtain a current acceleration signal collected by the sensor and calculate characteristic parameters of a current frequency band of the vehicle based on the current acceleration signal; a sum determination unit, configured to determine the sum of all high-frequency signals within a sampling period based on the current frequency band characteristic parameter; wherein the sampling period is pre-established based on the sampling frequency of the sensor; and the high-frequency signal refers to a frequency band characteristic parameter greater than a preset threshold; a threshold judgment unit, configured to judge whether the sum of all the high-frequency signals is not less than a high-frequency threshold; a time recording unit, configured to determine that the current body vibration state of the vehicle is a high-frequency vibration state if the sum of all the high-frequency signals is not less than a high-frequency threshold, and record the duration of the high-frequency vibration state; a time detection unit, configured to detect in real time whether the duration of the high-frequency vibration state meets a preset time threshold; The current starting unit is used to start the current compensation of the vehicle if the duration of the high-frequency vibration state recorded meets a preset time threshold, so as to control the semi-active suspension of the vehicle.

9. The device according to claim 8, characterized in that The parameter calculation unit includes: A signal acquisition unit, used to acquire the vehicle body vertical acceleration signal measured by the measurement unit; an integral processing unit, configured to perform integral processing on the current acceleration signal to obtain a vertical acceleration signal of the target vehicle body; The parameter calculation subunit is used to calculate the current frequency band characteristic parameters of the vehicle based on the vehicle body vertical acceleration signal, the target vehicle body vertical acceleration signal and a preset frequency limit.

10. The device according to claim 8, characterized in that The sum determination unit includes: A parameter acquisition unit, used to obtain characteristic parameters of all frequency bands within a sampling period; a deleting unit, configured to delete the first frequency band characteristic parameter in the sampling period and add the current frequency band characteristic parameter to the last frequency band characteristic parameter in the sampling period to obtain a new sampling period; an extraction unit, configured to extract all frequency band characteristic parameters greater than a preset threshold from the new sampling period, and use all frequency band characteristic parameters greater than the preset threshold as high-frequency signals; The summation sub-determination unit is configured to calculate the sum of all the high-frequency signals to obtain a target value, and determine the target value as the sum of all the high-frequency signals within a sampling period.

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