Control method of active suspension assembly, active suspension assembly and vehicle

Abstract

The application discloses a control method of an active suspension assembly, the active suspension assembly and a vehicle. The active suspension assembly comprises an active suspension, which is arranged between a vehicle body assembly and a tire assembly. The control method comprises the following steps: obtaining the natural frequency of the active suspension assembly; determining the estimated stiffness of the active suspension assembly according to the natural frequency and the mass of the vehicle body assembly; and adjusting the stiffness of the active suspension according to the estimated stiffness. The control method of the active suspension assembly, the active suspension assembly and the vehicle can determine the estimated stiffness of the active suspension assembly according to the natural frequency of the active suspension assembly and the mass of the vehicle body assembly, so that the stiffness of the active suspension can be adjusted by using the estimated stiffness of the active suspension assembly, and the parameter adjustment of the active suspension assembly is more accurate, and the comfort of the vehicle can be better maintained.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of active suspension, and in particular to a control method of an active suspension assembly, the active suspension assembly and a vehicle. BACKGROUND

[0002] In the related art, in order to improve the comfort of the vehicle during driving, the vehicle is equipped with an active suspension assembly to replace a passive suspension assembly, wherein the active suspension assembly can adjust parameters according to the state of the vehicle during driving. However, the parameter adjustment of the active suspension assembly in the related art is not accurate enough, so that the active suspension assembly cannot well maintain the comfort of the vehicle. SUMMARY

[0003] The embodiments of the present application provide a control method of an active suspension assembly, the active suspension assembly and a vehicle.

[0004] The control method of the embodiments of the present application is used for an active suspension assembly, the active suspension assembly comprising an active suspension configured to be arranged between a vehicle body assembly and a tire assembly, and the control method comprising: obtaining a natural frequency of the active suspension assembly; determining an estimated stiffness of the active suspension assembly according to the natural frequency and a mass of the vehicle body assembly; and adjusting a stiffness of the active suspension according to the estimated stiffness.

[0005] The control method of the active suspension assembly can determine the estimated stiffness of the active suspension assembly according to the natural frequency of the active suspension assembly and the mass of the vehicle body assembly, so that the stiffness of the active suspension can be adjusted by using the estimated stiffness of the active suspension assembly, and the parameter adjustment of the active suspension assembly can be more accurate, so that the active suspension assembly can well maintain the comfort of the vehicle. In addition, the estimated stiffness of the active suspension assembly is calculated in combination with the mass of the vehicle body assembly, so that the value of the estimated stiffness is more accurate, thereby facilitating the accurate adjustment of the parameters of the active suspension assembly and ensuring the comfort of the vehicle.

[0006] In some embodiments, the active suspension assembly further comprises a rack and a sensor for detecting movement of the rack, the rack being configured to be arranged on the tire assembly, and the sensor being configured to be arranged on the vehicle body assembly, and the obtaining of the natural frequency of the active suspension assembly comprises: controlling the sensor to collect a pulse signal formed when the rack passes the sensor; determining a pulse period corresponding to each tooth of the rack according to the pulse signal; and performing frequency spectrum analysis on the pulse period to obtain the natural frequency.

[0007] In some embodiments, the width of each tooth of the rack is the same, the width of each tooth gap between any two adjacent teeth is the same, the sensor is a Hall sensor, and the control of the sensor to collect the pulse signal formed when the rack passes the sensor includes: the Hall sensor generates a rising edge signal when the tooth passes; the Hall sensor generates a falling edge signal when the tooth gap passes; the rising edge signal and the falling edge signal together form the pulse signal; and the determination of the pulse period corresponding to each tooth based on the pulse signal includes: determining the sum of the time period of each rising edge signal and the corresponding falling edge signal as the pulse period.

[0008] In some embodiments, the frequency spectrum analysis of the pulse period to obtain the natural frequency includes: obtaining the peak value of the amplitude corresponding to each frequency in a preset frequency range; and determining the frequency corresponding to the peak value as the natural frequency.

[0009] In some embodiments, the determination of the estimated stiffness of the active suspension assembly based on the natural frequency and the mass of the vehicle body assembly includes: calculating the estimated stiffness by using the formula k = (f * 2 * π)2* m, where f is the natural frequency and m is the mass of the vehicle body assembly.

[0010] In some embodiments, the adjustment of the stiffness of the active suspension based on the estimated stiffness includes: determining a deviation value based on the estimated stiffness and a target stiffness; adjusting the stiffness of the active suspension based on the deviation value; updating the estimated stiffness and entering the determination of the deviation value based on the estimated stiffness and the target stiffness to achieve closed-loop control.

[0011] In some embodiments, the control method further includes: determining the Z-direction movement speed and the Z-direction acceleration of the active suspension based on the pulse signal; and adjusting the damping of the active suspension based on the Z-direction movement speed and the Z-direction acceleration.

[0012] In some embodiments, the determination of the Z-direction movement speed and the Z-direction acceleration of the active suspension based on the pulse signal includes: determining the current tooth and the current collection time corresponding to the sensor based on the pulse signal; determining the Z-direction displacement of the active suspension based on the current tooth and an initial tooth; determining the displacement duration of the active suspension based on the current collection time and an initial collection time; and determining the Z-direction movement speed and the Z-direction acceleration based on the Z-direction displacement and the displacement duration.

[0013] In some embodiments, the adjusting the damping of the active suspension according to the Z-direction motion speed and the Z-direction acceleration comprises: calculating a roughness of the road surface according to the Z-direction motion speed and the Z-direction acceleration; and adjusting the damping of the active suspension according to the roughness.

[0014] In some embodiments, the active suspension comprises at least one of an air suspension, a hydraulic suspension, an electromagnetic suspension, and an electronic hydraulic suspension.

[0015] The active suspension assembly of the embodiments of the present application comprises an active suspension arranged between a vehicle body assembly and a tire assembly, and a processor configured to obtain a natural frequency of the active suspension assembly, determine an estimated stiffness of the active suspension assembly according to the natural frequency and a mass of the vehicle body assembly, and adjust a stiffness of the active suspension according to the estimated stiffness.

[0016] The active suspension assembly can determine the estimated stiffness of the active suspension assembly according to the natural frequency of the active suspension assembly and the mass of the vehicle body assembly, so that the stiffness of the active suspension can be adjusted according to the estimated stiffness of the active suspension assembly, and the parameter adjustment of the active suspension assembly can be more accurate, and the comfort of the vehicle can be better maintained.

[0017] The vehicle of the embodiments of the present application comprises the active suspension assembly of the above-mentioned embodiments, a vehicle body assembly, and a tire assembly. The active suspension assembly is arranged between the vehicle body assembly and the tire assembly.

[0018] The vehicle can determine the estimated stiffness of the active suspension assembly according to the natural frequency of the active suspension assembly and the mass of the vehicle body assembly, so that the stiffness of the active suspension can be adjusted according to the estimated stiffness of the active suspension assembly, and the parameter adjustment of the active suspension assembly can be more accurate, and the comfort of the vehicle can be better maintained.

[0019] Additional aspects and advantages of the present application will be made apparent by the following description and the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0020] The above and / or additional aspects and advantages of the present application will become apparent and be readily appreciated from the following description, taken in conjunction with the accompanying drawings, in which:

[0021] Figure 1 is a flowchart of a control method of the active suspension assembly of the embodiments of the present application;

[0022] Figure 2 is a schematic diagram of a vehicle of the embodiments of the present application;

[0023] Figure 3 is a flowchart of a control method of an active suspension assembly according to an embodiment of the present invention;

[0024] Figure 4 is a schematic diagram of a pulse signal of a sensor according to an embodiment of the present invention;

[0025] Figure 5 is a flowchart of a control method of an active suspension assembly according to an embodiment of the present invention;

[0026] Figure 6 is a flowchart of a control method of an active suspension assembly according to an embodiment of the present invention;

[0027] Figure 7 is a schematic diagram of a frequency response curve according to an embodiment of the present invention;

[0028] Figure 8 is a flowchart of a control method of an active suspension assembly according to an embodiment of the present invention;

[0029] Figure 9 is a flowchart of a control method of an active suspension assembly according to an embodiment of the present invention;

[0030] Figure 10 is an example diagram of a control method of an active suspension assembly according to an embodiment of the present invention;

[0031] Figure 11 is a flowchart of a control method of an active suspension assembly according to an embodiment of the present invention;

[0032] Figure 12 is a flowchart of a control method of an active suspension assembly according to an embodiment of the present invention;

[0033] Figure 13 is a flowchart of a control method of an active suspension assembly according to an embodiment of the present invention. DETAILED DESCRIPTION

[0034] Embodiments of the present invention are described in detail below with reference to the attached drawings, wherein like or similar elements are denoted by the same or similar reference numerals throughout the drawings. The embodiments described below are exemplary only, and are not to be construed as limiting the present invention.

[0035] In the description of the embodiments of the present application, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, the meaning of "multiple" is two or more, unless otherwise explicitly specified.

[0036] Referring to Figure 1 and Figure 2 , the control method of the embodiments of the present application is used for the active suspension assembly 10. The active suspension assembly 10 comprises an active suspension 12 arranged between a vehicle body assembly 20 and a tire assembly 30. The control method comprises:

[0037] 01: obtaining the natural frequency of the active suspension assembly 10;

[0038] 03: determining the estimated stiffness of the active suspension assembly 10 according to the natural frequency and the mass of the vehicle body assembly 20;

[0039] 05: adjusting the stiffness of the active suspension 12 according to the estimated stiffness.

[0040] The control method of the active suspension assembly 10 of the embodiments of the present application can be implemented by the active suspension assembly 10 of the embodiments of the present application. Specifically, the active suspension assembly 10 comprises an active suspension 12, a rack 14, a sensor 16 for detecting the movement of the rack 14, and a processor (not shown in the figure) for obtaining the natural frequency of the active suspension assembly 10, and for determining the estimated stiffness of the active suspension assembly 10 according to the natural frequency and the mass of the vehicle body assembly 20, and for adjusting the stiffness of the active suspension 12 according to the estimated stiffness.

[0041] The control method of the active suspension assembly 10 and the active suspension assembly 10 described above, by the natural frequency of the active suspension assembly 10 and the mass of the vehicle body assembly 20, can determine the estimated stiffness of the active suspension assembly 10, so that the stiffness of the active suspension 12 can be regulated by using the estimated stiffness of the active suspension assembly 10, and thus the parameter regulation of the active suspension assembly 10 can be more accurate, and the active suspension assembly 10 can better maintain the comfort of the vehicle. In addition, the estimated stiffness of the active suspension assembly 10 is calculated in combination with the mass of the vehicle body assembly 20, so that the value of the estimated stiffness is more accurate, thereby facilitating accurate regulation of the parameters of the active suspension assembly 10 and ensuring the comfort of the vehicle.

[0042] Specifically, the active suspension 12 includes at least one of an air suspension, a hydraulic suspension, an electromagnetic suspension, and an electronic hydraulic suspension. The active suspension 12 is disposed between the body assembly 20 and the tire assembly 30. It is understood that the active suspension 12 includes at least two mounting portions, one of which is fixedly connected to the body assembly 20 and the other to the tire assembly 30. During vehicle travel, the road surface generates random excitations on the tire assembly 30, which are transmitted to the body assembly 20 via the active suspension 12. The active suspension 12 can attenuate the random excitations transmitted to the body assembly 20, thereby ensuring vehicle comfort. The natural frequency can be understood as the frequency value calculated from the random excitations generated by the road surface on the tire assembly 30. The mass of the body assembly 20 can be obtained through vehicle factory information or weight sensor detection. Furthermore, after obtaining the natural frequency and the mass of the vehicle body component 20, the estimated stiffness of the active suspension component 10 can be calculated using a mathematical formula, and the stiffness of the active suspension 12 can be adjusted based on the calculated estimated stiffness to reduce the impact of random road excitation on the vehicle body stability and better maintain the comfort of the vehicle.

[0043] See also Figure 3 In some embodiments, the active suspension assembly 10 further includes a rack 14 and a sensor 16 for detecting movement of the rack 14. The rack 14 is configured to be disposed on the tire assembly 30. The sensor 16 is configured to be disposed on the vehicle body assembly 20. Step 01 includes:

[0044] 011: Control the sensor 16 to collect the pulse signal generated when the rack 14 passes through the sensor 16;

[0045] 013: Determine the pulse period corresponding to each tooth 142 of the rack 14 according to the pulse signal;

[0046] 015: Perform spectrum analysis on the pulse period to obtain the natural frequency.

[0047] The control method of the active suspension assembly 10 of the above embodiment can be implemented by the active suspension assembly 10 of the embodiment of the present invention. Specifically, the processor is configured to control the sensor 16 to collect the pulse signal generated when the rack 14 passes the sensor 16, to determine the pulse period corresponding to each tooth 142 of the rack 14 based on the pulse signal, and to perform spectrum analysis on the pulse period to obtain the natural frequency.

[0048] Thus, by analyzing the pulse signals collected by the sensor 16, the natural frequency corresponding to the random excitation of the tire assembly 30 by the road surface is obtained. Specifically, the sensor 16 can include a Hall sensor, an infrared sensor, an image sensor, etc. The number of the rack 14 and the sensor 16 can be one pair or two pairs. When the number of the rack 14 and the sensor 16 is two pairs, one pair of the rack 14 and the sensor 16 can be arranged on the left side of the vehicle, and the other pair of the rack 14 and the sensor 16 can be arranged on the right side of the vehicle; or one pair of the rack 14 and the sensor 16 is arranged on the front side of the vehicle, and the other pair of the rack 14 and the sensor 16 is arranged on the rear side of the vehicle, so as to better collect the pulse signals. Figure 2 In the embodiment shown, the sensor 16 is a Hall sensor, which includes a detection end. The detection end of the Hall sensor is arranged opposite the tooth 142 of the rack 14, and the rack 14 and the Hall sensor form a straight-line Hall sensor. During the driving of the vehicle, the tire assembly 30 is excited randomly by the road surface, and the tire assembly 30 vibrates up and down. The rack 14 vibrates synchronously with the tire assembly 30. When the rack 14 vibrates up and down with the tire assembly 30, the movement of the rack 14 detected by the detection end of the Hall sensor forms a pulse signal corresponding to the rack 14. In this way, the vibration of the tire assembly 30 is converted into a PWM signal (as shown in FIG. 2) with a changing pulse period. The higher the vibration frequency of the rack 14, the faster the signal changes. Figure 4

[0049] Further, the rack 14 includes a plurality of teeth 142 and a plurality of tooth grooves 144, and a tooth groove 144 is formed between any two teeth 142. In step 013, the pulse period corresponding to each tooth 142 of the rack 14, that is, the time length between the time when one tooth 142 passes through the detection end of the Hall sensor and the time when another tooth 142 passes through the detection end of the Hall sensor, that is, the pulse period corresponding to one tooth 142 of the rack 14 includes the total time length of the tooth 142 and the adjacent tooth groove 144 passing through the Hall sensor.

[0050] In step 015, since the vehicle body assembly 20, the active suspension assembly 10, and the tire assembly 30 form a two-degree-of-freedom system, the two-degree-of-freedom dynamics equation is M * d 2 ​X / dt + C*dx / dt + k*x = F, where M is a mass matrix, C is a damping matrix, K is a stiffness matrix, and F is a random excitation. In the present method, M = [m1 0; 0 m2], C = [c1 -c1; -c1 c1+c2], K = [k1 -k1; -k1 k1+k2], where m1 is the mass of the body assembly 20, m2 is the mass of the tire assembly 30, c1 is the damping of the active suspension 12, c2 is the damping of the tire assembly 30, k1 is the stiffness of the active suspension 12, and k2 is the stiffness of the tire assembly 30. The damping has a small effect on the natural frequency of the active suspension assembly 10, so it can be ignored.

[0051] Further, the Laplace transform of the two-degree-of-freedom dynamic equation gives the system frequency transfer function as G(s) = X(s) / F(s), where F(s) is the Laplace transform of the random excitation and X(s) is the Laplace transform of the Z-direction displacement of the active suspension. The system frequency transfer function, i.e., G(s), describes the response of the active suspension assembly 10 to different frequency inputs. The frequency response curve (as shown in FIG. 3) can be plotted from the system frequency transfer function. It can be seen that the active suspension assembly 10 is sensitive to the first order input, i.e., the natural frequency of the body assembly 20. Therefore, when the road random excitation is input to the active suspension assembly 10 through the tire assembly, the active suspension assembly 10 will reflect the vibration amplitude, so that the natural frequency can be obtained through frequency spectrum analysis, achieving the effect of stiffness estimation. Figure 7

[0052] Please refer to Figure 5 In some embodiments, each tooth 142 of the rack 14 has the same width. The width of the tooth gap 144 between any two adjacent teeth 142 is the same. The sensor 16 is a Hall sensor. Step 011 includes:

[0053] 0111: the Hall sensor generates a rising edge signal when a tooth 142 passes by;

[0054] 0113: the Hall sensor generates a falling edge signal when a tooth gap 144 passes by;

[0055] 0115: the rising edge signal and the falling edge signal together form a pulse signal;

[0056] Step 013 includes:

[0057] 0131: determine the sum of the time periods of each rising edge signal and the corresponding falling edge signal as a pulse period.

[0058] ​The control method of the active suspension assembly 10 of the above embodiment can be implemented by the active suspension assembly 10 of the embodiment of the present application. Specifically, the processor is configured to generate a rising edge signal when the Hall sensor passes the tooth 142, and generate a falling edge signal when the Hall sensor passes the tooth groove 144, and generate a pulse signal based on the rising edge signal and the falling edge signal, and determine the sum of the time periods of each rising edge signal and the corresponding falling edge signal as a pulse period.

[0059] In this way, the Hall sensor can accurately record the pulse signal corresponding to the up-down vibration of the rack 14, and facilitate the determination of the pulse period. Specifically, the Hall sensor includes a detection end, please refer to Figure 4 When a tooth 142 starts to pass the detection end, the Hall sensor generates a rising edge signal; when a tooth groove 144 starts to pass the detection end, the Hall sensor generates a falling edge signal. It should be noted that the rising edge signal corresponds to Figure 4 the middle-high level line segment, and the falling edge signal corresponds to Figure 4 the middle-low level line segment, and the high level line segment and the low level line segment together form a pulse signal, that is, correspond to Figure 4 the curve in the figure. Taking the sum of the time periods of each rising edge signal and the falling edge signal after and adjacent to the rising edge signal as a pulse period, or taking the sum of the time periods of each rising edge signal and the falling edge signal before and adjacent to the rising edge signal as a pulse period, and then performing frequency spectrum analysis on the pulse period can obtain the natural frequency.

[0060] It should be noted that the width of the tooth 142 and the width of the tooth groove 144 can be the same or different, that is, the width of the tooth 142 can be greater than the width of the tooth groove 144; the width of the tooth 142 can also be smaller than the width of the tooth groove 144, which is not limited here.

[0061] Please refer to Figure 6 In some embodiments, step 015 includes:

[0062] 0151: obtaining the peak value of the amplitude corresponding to each frequency in the preset frequency range;

[0063] 0153: determining the frequency corresponding to the peak value as the natural frequency.

[0064] The control method of the active suspension assembly 10 of the above embodiment can be implemented by the active suspension assembly 10 of the embodiment of the present application. Specifically, the processor is configured to obtain the peak value of the amplitude corresponding to each frequency in the preset frequency range, and determine the frequency corresponding to the peak value as the natural frequency.

[0065] Thus, by detecting the amplitudes corresponding to each frequency in the preset frequency range, the natural frequency can be determined according to the peak value of the amplitudes. In one example, the frequency range of the random excitation of the road acting on the tire assembly 30 is 0-15 Hz, i.e. the frequency range of the spectrum analysis is 0-15 Hz, and further, the preset frequency range is 0-5 Hz, the pulse period is spectrum analyzed, if a peak value appears in the frequency range of 0-5 Hz, the frequency corresponding to the peak value is the natural frequency (as shown in FIG. 6). Figure 7

[0066] Referring to Figure 8 In some embodiments, step 03 comprises:

[0067] 031: calculating the estimated stiffness by using the formula k = (f * 2 * π) 2 * m, where f is the natural frequency and m is the mass of the vehicle body assembly 20.

[0068] The control method of the active suspension assembly 10 of the above embodiments can be implemented by the active suspension assembly 10 of the embodiments of the present application. Specifically, the processor is configured to calculate the estimated stiffness by using the formula k = (f * 2 * π) 2 * m.

[0069] Thus, the estimated stiffness of the active suspension assembly 10 can be determined according to the natural frequency and the mass of the vehicle body assembly 20. Specifically, after obtaining the natural frequency and the mass of the vehicle body assembly 20, the values of the natural frequency and the mass of the vehicle body assembly 20 are substituted into the formula, and the value of k, i.e. the estimated stiffness, is calculated.

[0070] Referring to Figure 9 In some embodiments, step 05 comprises:

[0071] 051: determining the deviation value according to the estimated stiffness and the target stiffness;

[0072] 053: adjusting the stiffness of the active suspension 12 according to the deviation value;

[0073] 055: updating the estimated stiffness and entering step 051 to realize closed-loop control.

[0074] The control method of the active suspension assembly 10 of the above embodiments can be implemented by the active suspension assembly 10 of the embodiments of the present application. Specifically, the processor is configured to determine the deviation value according to the estimated stiffness and the target stiffness, and to adjust the stiffness of the active suspension 12 according to the deviation value, and to update the estimated stiffness and enter the step of determining the deviation value according to the estimated stiffness and the target stiffness to realize closed-loop control.

[0075] ​Therefore, by comparing the estimated stiffness and the target stiffness to determine the deviation value, and then adjusting the stiffness of the active suspension 12 according to the deviation value, the parameter control of the active suspension assembly 10 is more accurate, and the comfort of the vehicle is maintained. Specifically, the target stiffness can be a stiffness value calibrated in advance according to different road conditions. The way to adjust the stiffness of the active suspension 12 according to the deviation value includes but is not limited to adjusting the air volume of the active suspension 12, the extension and retraction amount of the hydraulic cylinder, etc.

[0076] In one example, the active suspension 12 is an air suspension, and the air suspension includes an air spring. Please refer to Figure 10 After obtaining the estimated stiffness, the air volume of the air spring is accurately adjusted by proportional-integral-derivative control according to the deviation value between the target stiffness and the estimated stiffness, so as to change the stiffness of the air suspension and maintain the comfort and stability of the vehicle.

[0077] Please refer to Figure 11 In some embodiments, the control method further comprises:

[0078] 017: determining the Z-direction motion speed and the Z-direction acceleration of the active suspension 12 according to the pulse signal;

[0079] 019: adjusting the damping of the active suspension 12 according to the Z-direction motion speed and the Z-direction acceleration.

[0080] The control method of the active suspension assembly 10 of the above-mentioned embodiments can be implemented by the active suspension assembly 10 of the embodiments of the present application. Specifically, the processor is configured to determine the Z-direction motion speed and the Z-direction acceleration of the active suspension 12 according to the pulse signal, and to adjust the damping of the active suspension 12 according to the Z-direction motion speed and the Z-direction acceleration.

[0081] Therefore, the road conditions can be estimated by using the calculated Z-direction motion speed and Z-direction acceleration of the active suspension 12, and the damping of the active suspension 12 is adjusted, so that the vehicle has better comfort and stability. It can be understood that the Z-direction motion speed is the motion speed of the active suspension 12 in the vertical direction, and the Z-direction acceleration is the acceleration of the active suspension 12 in the vertical direction. The Z-direction motion speed and the Z-direction acceleration can reflect the motion state of the active suspension 12 in the vertical direction, and further, the Z-direction motion speed and the Z-direction acceleration of the active suspension 12 can reflect the actual roughness of the road.

[0082] Please refer to Figure 12 In some embodiments, step 017 comprises:

[0083] 0171: determining the current tooth 142 corresponding to the sensor 16 and the current acquisition time according to the pulse signal;

[0084] 0173: determine the Z-direction displacement of the active suspension 12 according to the current tooth 142 and the initial tooth 142;

[0085] 0175: determine the displacement duration of the active suspension 12 according to the current collection time and the initial collection time;

[0086] 0177: determine the Z-direction movement speed and the Z-direction acceleration according to the Z-direction displacement and the displacement duration.

[0087] The control method of the active suspension assembly 10 of the above embodiment can be implemented by the active suspension assembly 10 of the embodiment of the present application. Specifically, the processor is configured to determine the current tooth 142 and the current collection time corresponding to the sensor 16 according to the pulse signal, and to determine the Z-direction displacement of the active suspension 12 according to the current tooth 142 and the initial tooth 142, and to determine the displacement duration of the active suspension 12 according to the current collection time and the initial collection time, and to determine the Z-direction movement speed and the Z-direction acceleration according to the Z-direction displacement and the displacement duration.

[0088] In this way, in combination with the formula, the Z-direction movement speed and the Z-direction acceleration of the active suspension 12 can be determined according to the pulse signal, thereby providing a basic parameter for the control of the active suspension 12. It can be understood that the Z-direction displacement is the displacement of the active suspension 12 in the vertical direction, and the greater the value of the Z-direction displacement, the more obvious the movement of the active suspension 12 in the vertical direction, and the more intense the vehicle bumping. Specifically, the sensor 16 includes a Hall sensor, and in some embodiments, the detection end of the Hall sensor has a direction detection function. During the driving of the vehicle, the detection end can detect the movement direction of the tooth 142 of the rack 14 relative to the detection end, thereby being able to identify the current tooth 142 and the initial tooth 142, and further being able to calculate the Z-direction displacement of the active suspension 12.

[0089] In one example, after the vehicle is powered on, the rack 14 encoding program is started, and the first rising edge signal is recorded as tooth 1. When the rising edge signal in the same movement direction is detected, the tooth sequence is increased by 1. When the rising edge signal in the same movement direction is detected, the tooth sequence is decreased by 1. In this way, the specific position of the rack 14 corresponding to the Hall sensor can be determined. Since the width of each tooth 142 is the same, and the width of each tooth groove 144 is also the same, the distance between the current tooth 142 and the initial tooth 142 can be calculated according to the tooth sequence. It can be understood that the tooth 142 corresponding to the first rising edge signal received after each power-on can be defined as the initial tooth 142, and the time when the first rising edge signal appears can be defined as the initial collection time.

[0090] Further, after determining the current tooth 142 corresponding to the sensor 16 and the current acquisition time, the Z-direction displacement x of the active suspension 12 can be determined by the difference between the position corresponding to the tooth sequence of the current tooth 142 and the position corresponding to the tooth sequence of the initial tooth 142, and the displacement time t of the active suspension 12 can be determined by the difference between the current acquisition time and the initial acquisition time, and then the Z-direction movement speed v = dx / dt and the Z-direction acceleration a = dv / dt = d 2 x / dt 2 .

[0091] Please refer to Figure 13 In some embodiments, step 019 comprises:

[0092] 0191: calculating the roughness of the road surface according to the Z-direction movement speed and the Z-direction acceleration;

[0093] 0193: adjusting the damping of the active suspension 12 according to the roughness.

[0094] The control method of the active suspension assembly 10 of the above-mentioned embodiments can be implemented by the active suspension assembly 10 of the embodiments of the present application. Specifically, the processor is configured to calculate the roughness of the road surface according to the Z-direction movement speed and the Z-direction acceleration, and to adjust the damping of the active suspension 12 according to the roughness.

[0095] In this way, the damping of the active suspension 12 is adjusted according to the roughness of the road surface, which can make the vehicle have better comfort and stability. Specifically, in some embodiments, the corresponding relationship between the roughness of different road surfaces and the Z-direction movement speed and the Z-direction acceleration of the active suspension 12 is tested in advance and stored, so that when the Z-direction movement speed and the Z-direction acceleration of the active suspension 12 are determined during the driving of the vehicle, the roughness of the road surface can be determined according to the corresponding relationship, and further, the damping of the active suspension 12 is adjusted according to the preset relationship between the roughness and the damping of the active suspension 12.

[0096] It should be noted that the specific numerical values mentioned above are only used as examples to illustrate the embodiments of the present application, and should not be understood as a limitation of the present application. In other examples or embodiments or examples, other numerical values can be selected according to the present application, which are not specifically limited here.

[0097] The vehicle 100 of the embodiments of the present application comprises the active suspension assembly 10, the vehicle body assembly 20 and the tire assembly 30 of the above-mentioned embodiments. The active suspension assembly 10 is arranged between the vehicle body assembly 20 and the tire assembly 30.

[0098] The above-mentioned vehicle 100 can determine the estimated stiffness of the active suspension component 10 through the natural frequency of the active suspension component 10 and the mass of the body component 20, so that the stiffness of the active suspension 12 can be regulated by using the estimated stiffness of the active suspension component 10, thereby making the parameter regulation of the active suspension component 10 more precise, so that the active suspension component 10 can better maintain the comfort of the vehicle 100.

[0099] Specifically, the vehicle 100 includes but is not limited to a pure electric vehicle, a hybrid electric vehicle, an extended-range electric vehicle, a fuel vehicle, and the like.

[0100] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0101] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0102] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A control method for an active suspension assembly, characterized in that: The active suspension assembly includes an active suspension, and the active suspension is used to be arranged between a vehicle body assembly and a tire assembly. The control method includes: Obtaining a natural frequency of the active suspension component; determining an estimated stiffness of the active suspension component based on the natural frequency and the mass of the vehicle body component; Adjusting the stiffness of the active suspension according to the estimated stiffness includes: Determining a deviation value based on the estimated stiffness and a target stiffness, wherein the target stiffness is a stiffness value pre-calibrated according to different road conditions; adjusting the stiffness of the active suspension according to the deviation value; The estimated stiffness is updated and the step of determining a deviation value according to the estimated stiffness and the target stiffness is entered to implement closed-loop control.

2. The control method according to claim 1, characterized in that: The active suspension assembly further includes a rack and a sensor for detecting movement of the rack, wherein the rack is configured to be disposed on the tire assembly and the sensor is configured to be disposed on the vehicle body assembly; The obtaining of the natural frequency of the active suspension component includes: Controlling the sensor to collect the pulse signal generated when the rack passes through the sensor; determining a pulse period corresponding to each tooth of the rack according to the pulse signal; A spectrum analysis is performed on the pulse period to obtain the natural frequency.

3. The control method according to claim 2, characterized in that: The width of each tooth of the rack is the same, the width of the tooth groove between any two adjacent teeth is the same, and the sensor is a Hall sensor; The controlling the sensor to collect a pulse signal generated when the rack passes through the sensor includes: The Hall sensor generates a rising edge signal when the tooth passes by; The Hall sensor generates a falling edge signal when the tooth slot passes; The rising edge signal and the falling edge signal together form the pulse signal; The determining the pulse period corresponding to each tooth according to the pulse signal includes: The sum of the time periods of each rising edge signal and the corresponding falling edge signal is determined as the pulse period.

4. The control method according to claim 2, characterized in that: The performing spectrum analysis on the pulse period to obtain the natural frequency includes: Get the peak value of the amplitude corresponding to each frequency within the preset frequency range; The frequency corresponding to the peak is determined as the natural frequency.

5. The control method according to claim 1, characterized in that: Determining the estimated stiffness of the active suspension component based on the natural frequency and the mass of the vehicle body component includes: Using the formula k=(f*2*π) 2 *m calculates the estimated stiffness, where f is the natural frequency and m is the mass of the vehicle body component.

6. The control method according to claim 2, characterized in that: The control method further includes: determining a Z-direction motion velocity and a Z-direction acceleration of the active suspension according to the pulse signal; The damping of the active suspension is adjusted according to the Z-direction movement speed and the Z-direction acceleration.

7. The control method according to claim 6, characterized in that: Determining the Z-direction motion speed and Z-direction acceleration of the active suspension according to the pulse signal includes: Determining the current tooth and current acquisition time corresponding to the sensor according to the pulse signal; Determining a Z-direction displacement of the active suspension according to the current tooth and the initial tooth; determining a displacement duration of the active suspension according to the current acquisition time and the initial acquisition time; The Z-direction motion speed and the Z-direction acceleration are determined according to the Z-direction displacement and the displacement duration.

8. The control method according to claim 6, characterized in that: The adjusting the damping of the active suspension according to the Z-direction motion speed and the Z-direction acceleration includes: Calculating the roughness of the road surface according to the Z-direction movement speed and the Z-direction acceleration; The damping of the active suspension is adjusted according to the roughness.

9. The control method according to any one of claims 1 to 8, characterized in that: The active suspension includes at least one of an air suspension, a hydraulic suspension, an electromagnetic suspension, and an electronic hydraulic suspension.

10. An active suspension assembly, characterized in that: The active suspension assembly includes an active suspension and a processor, wherein the active suspension is arranged between a vehicle body assembly and a tire assembly, the processor is configured to obtain a natural frequency of the active suspension assembly, determine an estimated stiffness of the active suspension assembly based on the natural frequency and a mass of the vehicle body assembly, and adjust the stiffness of the active suspension based on the estimated stiffness; Among them, the processor is specifically used to determine the deviation value based on the estimated stiffness and the target stiffness, the target stiffness is a stiffness value pre-calibrated according to different road conditions, and is used to adjust the stiffness of the active suspension according to the deviation value, and to update the estimated stiffness and enter the process of determining the deviation value based on the estimated stiffness and the target stiffness to achieve closed-loop control.

11. A vehicle, characterized in that: The vehicle comprises the active suspension assembly according to claim 10 , a body assembly, and a tire assembly, wherein the active suspension assembly is arranged between the body assembly and the tire assembly.

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