Method and device for controlling semi-active suspension based on road surface recognition

Abstract

The invention discloses a semi-active suspension control method and device based on road surface recognition, and the method comprises the steps: periodically obtaining 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 the sampling period according to the current frequency band characteristic parameters; judging whether the sum of all the high-frequency signals is not less than a high-frequency threshold; if not, determining that the current vehicle 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 recording the high-frequency vibration state meets a preset time threshold value or not in real time; and if the preset time threshold value is met, current compensation of the vehicle is started to control a semi-active suspension of the vehicle. Therefore, the excitation form of the vehicle is identified through the road surface identification process, then current compensation is determined to control the semi-active suspension of the vehicle, hardware intervention is not needed, and the hardware cost is effectively reduced.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a control method and device for a semi-active suspension based on road surface recognition. Background Art

[0002] Semi-active suspension adds an electronic control system to passive suspension, which can adjust the damping force according to real-time road conditions and driving requirements, thereby improving the comfort and handling of the vehicle. Therefore, when road conditions change, how to make the control strategy quickly adapt to and meet the rapid changes in vehicle dynamic performance is a key problem that must be overcome in the development of semi-active suspension.

[0003] In the existing technology, the offline analysis method is mainly used, that is, the vertical acceleration signal at a certain position of the vehicle body is converted into a power spectrum density by Fourier transform 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 real-time performance of Fourier transform is difficult to guarantee and requires high computing power from the controller, which results in the use of chips with Fourier transform processing increasing the control cost. Summary of the invention

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

[0006] In order to achieve the above objectives, this application provides the following technical solutions:

[0007] The first aspect of the present application provides a control method for a semi-active suspension based on road surface recognition, 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 characteristic parameters of the current frequency band, the sum of all high-frequency signals within a sampling period is determined; wherein the sampling period is created in advance according to the sampling frequency of the sensor; and the high-frequency signal refers to a frequency band characteristic parameter greater than a preset threshold;

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

[0011] 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;

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

[0013] If the duration of the high-frequency vibration state recorded 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 control method of the semi-active suspension based on road surface recognition, the calculating of the current frequency band characteristic parameters of the vehicle according to the current acceleration signal includes:

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

[0016] Performing integration processing on 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 control method of the semi-active suspension based on road surface recognition, determining the sum of all high-frequency signals within the sampling period according to the characteristic parameters of the current frequency band 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 position 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 using 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 within a sampling period.

[0023] Optionally, in the above-mentioned control method of the semi-active suspension based on road surface recognition, after judging 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 control method of semi-active suspension based on road surface recognition, it also 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 duration of the low-frequency vibration state recorded 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 control method of semi-active suspension based on road surface recognition, it also includes:

[0033] 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 when the duration of recording 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, used to periodically obtain a current acceleration signal collected by a sensor, and calculate a current frequency band characteristic parameter of the vehicle according to the current acceleration signal;

[0036] A sum determination unit, configured to determine the sum of all high-frequency signals within a sampling period according to the current frequency band characteristic parameter; wherein the sampling period is pre-created according to 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, used 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 the high-frequency threshold, and record the duration of the high-frequency vibration state;

[0039] A time detection unit, used for detecting and recording 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 to control the semi-active suspension of the vehicle if the duration of the high-frequency vibration state recorded meets a preset time threshold.

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

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

[0043] An integral processing unit, used for performing integral processing on the current acceleration signal to obtain a vertical acceleration signal of a 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 acquire characteristic parameters of all frequency bands within a sampling period;

[0047] A deleting unit, 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;

[0048] An extraction unit, 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;

[0049] The sum sub-determination unit is used 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, in the above-mentioned control device for semi-active suspension based on road surface recognition, it further includes:

[0051] The determination unit is used 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 the high-frequency threshold.

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

[0053] The zeroing 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, in the above-mentioned control device for semi-active suspension based on road surface recognition, it further includes:

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

[0056] A detection unit, used for detecting and recording 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, in the above-mentioned control device for semi-active suspension based on road surface recognition, it further includes:

[0060] 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 the preset time threshold.

[0061] The present application provides a control method for a semi-active suspension based on road surface recognition, which periodically obtains the current acceleration signal collected by the sensor, and calculates the current frequency band characteristic parameters of the vehicle according to the current acceleration signal, and then determines the sum of all high-frequency signals in the sampling period according to the current frequency band characteristic parameters, wherein the sampling period is created in advance according to the frequency of sensor sampling, and the high-frequency signal refers to the frequency band characteristic parameters greater than the preset threshold, and then determines whether the sum of all high-frequency signals is not less than the high-frequency threshold, and if the sum of all high-frequency signals is not less than the high-frequency threshold, 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, and finally, it is detected in real time whether the duration of the high-frequency vibration state meets the preset time threshold, and if the duration of the high-frequency vibration state meets the preset time threshold, the current compensation of the vehicle is turned on to control the semi-active suspension of the vehicle. Thus, the excitation form of the vehicle is identified through the road surface recognition process, and then the current compensation is determined to control the semi-active suspension of the vehicle, and then no hardware intervention is required, which effectively reduces the problem of hardware cost. 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 drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0063] Figure 1 A schematic diagram of the structure 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 schematic diagram of a flow chart of a method for calculating frequency band characteristic parameters provided in another embodiment of the present application;

[0066] Figure 4 A schematic flow chart 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 an 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 the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work 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 "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including 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, if 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 according to 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 according to 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 of a semi-active suspension based on road surface recognition, such as Figure 2 As shown, the specific steps include:

[0078] S201. Periodically obtain a current acceleration signal collected by a sensor, and calculate a current frequency band characteristic parameter of the vehicle according to the current acceleration signal.

[0079] Specifically, in order to control the semi-active suspension on bumpy roads to improve the user's comfort, in the 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, so as to control 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 condition is 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 frequency band characteristic parameters of the vehicle can be determined by collecting the acceleration signal of the vehicle, so as to characterize the influence of the current road environment on the vehicle body vibration by means of the frequency band characteristic parameters, whether it 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 measuring unit.

[0082] Specifically, the vertical acceleration signal of the vehicle body during driving can be directly measured by an inertial measurement unit (IMU) installed at the center of mass of the vehicle body. The vertical acceleration signal of the vehicle body refers to the acceleration of the vehicle in the vertical direction (usually the depth direction) relative to the ground. It is usually related to the vibration, bumps and vibration frequency of the vehicle.

[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 of the characteristic parameters of the current frequency band is:

[0088]

[0089] in, is the vehicle body vertical acceleration signal, is the vertical acceleration signal of the target vehicle body, a is the preset frequency limit between high frequency and low frequency, and the value of a should be set at the damping fixed point in suspension control, which is 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 created in advance according to the sampling frequency of the sensor. The high-frequency signal refers to a frequency band characteristic parameter greater than a preset threshold.

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

[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: Obtain 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 frequency band characteristic parameters are fully written in the sampling period, when a new frequency band characteristic parameter is 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 stimulus received by the current vehicle and achieve the effect of sliding recording of real-time signals.

[0097] For example, assuming that the length of the time window of the sampling cycle is 10, the frequency band selector will start calculating the characteristic parameter F from the moment the vehicle is powered on, running once every 2ms, and each calculated result will be stored in the sampling cycle. The sampling cycle will count the number of characteristic parameters F in the window that are greater than 0, and output the specific number for output. Otherwise, the output result is 0. After 10 cycles, the statistical time window will be full of characteristic parameters F. When a new characteristic parameter F is stored in the 11th cycle, the characteristic parameter F calculated in the first position of the time window (i.e., the first cycle) will be deleted, and the characteristic parameter F result of the 11th cycle will be stored in the last position of the window (i.e., the characteristic parameters F of the 2nd to 11th cycles are retained in the window).

[0098] S403: 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.

[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 a 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 affected by the high-frequency band on the vehicle body 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 know whether the road excitation currently received by 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 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 means a high-frequency vibration state, and therefore 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 that 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, during the recording of 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 process 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 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 when 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, the duration of the high-frequency vibration state needs to be set to 0 to avoid turning on the current compensation. In addition, the duration is re-recorded the next time the current body vibration state of the vehicle is a high-frequency vibration state.

[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 recording the high-frequency vibration state meets 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 the user's comfort.

[0119] For example, when the suspension is subjected to high-frequency excitation from the road, if the shock absorber can maintain a softer damping state, it can better filter out the vibration of the road. Assuming that the current suspension is not in a soft state, the current compensation in this way can lower the working current of the current suspension shock absorber, so that it can maintain a softer state to better improve the comfort of the passengers.

[0120] Optionally, after current compensation is turned on, the vibration state of the vehicle 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 will 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, but will exit only when the duration of the low-frequency vibration state meets the preset time threshold. 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 from the moment the current body vibration state of the vehicle is a low-frequency vibration state.

[0123] S502: Real-time detection and recording of 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 means that the current compensation needs to be exited, so step S503 is executed. If the duration of the low-frequency vibration state recorded does not meet the preset time threshold, it means that the current compensation cannot be exited, and the duration of the low-frequency vibration state needs to be continuously recorded until the duration of the low-frequency vibration state recorded meets the preset time threshold, so the process returns to the duration of the low-frequency vibration state recorded in step S501.

[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 current compensation of the vehicle to avoid affecting the stability of the system.

[0127] Optionally, during the recording of 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 timely process the vehicle in the high-frequency vibration state and provide the user with a better experience, in another embodiment of the present application, after executing step S501, the following further comprises:

[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, 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] The present application provides a control method for a semi-active suspension based on road surface recognition, which periodically obtains the current acceleration signal collected by the sensor, and calculates the current frequency band characteristic parameters of the vehicle according to the current acceleration signal, and then determines the sum of all high-frequency signals in the sampling period according to the current frequency band characteristic parameters, wherein the sampling period is created in advance according to the frequency of sensor sampling, and the high-frequency signal refers to the frequency band characteristic parameters greater than the preset threshold, and then determines whether the sum of all high-frequency signals is not less than the high-frequency threshold, and if the sum of all high-frequency signals is not less than the high-frequency threshold, 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, and finally, it is detected in real time whether the duration of the high-frequency vibration state meets the preset time threshold, and if the duration of the high-frequency vibration state meets the preset time threshold, the current compensation of the vehicle is turned on to control the semi-active suspension of the vehicle. Thus, the excitation form of the vehicle is identified through the road surface recognition process, and then the current compensation is determined to control the semi-active suspension of the vehicle, and then no hardware intervention is required, which effectively reduces the problem of hardware cost.

[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 according to the current acceleration signal.

[0134] The sum determination unit 702 is used to determine the sum of all high-frequency signals in a sampling period according to the current frequency band characteristic parameter. The sampling period is pre-created according to the frequency of sensor sampling. The high-frequency signal refers to the frequency band characteristic parameter greater than a preset threshold.

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

[0136] The time recording unit 704 is used 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 used 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 by 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 measuring unit.

[0142] The integral processing unit is used to perform integral processing on the current acceleration signal to obtain a 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 by another embodiment of the present application, the sum determination unit 702 includes:

[0145] The parameter acquisition unit is used to acquire 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 sum 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, in another embodiment of the present application, a control device for a semi-active suspension based on road surface recognition further includes:

[0150] The determination unit is used 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, in another embodiment of the present application, a control device for a semi-active suspension based on road surface recognition further includes:

[0152] The zeroing 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.

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

[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 used 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 used to return to execute the recording of the duration of the low-frequency vibration state if the duration of the low-frequency vibration state does not meet the preset time threshold.

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

[0159] The start-up unit is used to start 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 of 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 composition and steps of each example have been generally described in the above description according to function. 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 to be beyond the scope of this application.

[0163] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those 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 will not be limited to the embodiments shown herein, but will 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 according to the current acceleration signal; According to the characteristic parameters of the current frequency band, the sum of all high-frequency signals within a sampling period is determined; wherein the sampling period is created in advance according to 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 duration of the high-frequency vibration state recorded meets a preset time threshold, the 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: The calculating, according to the current acceleration signal, the current frequency band characteristic parameter of the vehicle includes: Acquire 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 step of 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 position 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 using 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, characterized in that 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, characterized in that 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 duration of the low-frequency vibration state recorded 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 duration of recording the low-frequency vibration state, and when the duration of recording 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, used to periodically obtain a current acceleration signal collected by a sensor, and calculate a current frequency band characteristic parameter of the vehicle according to the current acceleration signal; A sum determination unit, configured to determine the sum of all high-frequency signals within a sampling period according to the current frequency band characteristic parameter; wherein the sampling period is created in advance according to 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, used 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 the high-frequency threshold, and record the duration of the high-frequency vibration state; A time detection unit, used for detecting and recording 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 to control the semi-active suspension of the vehicle if the duration of the high-frequency vibration state recorded meets a preset time threshold.

9. The device according to claim 8, characterized in that The parameter calculation unit comprises: A signal acquisition unit, used to acquire a vehicle body vertical acceleration signal measured by the measurement unit; An integral processing unit, used for performing integral processing on the current acceleration signal to obtain a vertical acceleration signal of a 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 comprises: A parameter acquisition unit, used to acquire characteristic parameters of all frequency bands within a sampling period; A deleting unit, 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; An extraction unit, 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; The sum sub-determination unit is used 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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