Noise control method, suspension system and off-road vehicle

Abstract

The invention discloses a noise control method, a suspension system and an off-road vehicle, and relates to the technical field of vehicle noise control, and the suspension system comprises a suspension structure, two hydraulic cylinders and two sound pressure sensors; the suspension structure is provided with two cross beams extending in the horizontal direction and spaced in the vertical direction and two stand columns extending in the vertical direction and spaced in the horizontal direction, and the stand columns are connected with the ends, on the same side, of the two cross beams respectively. One ends of the two hydraulic cylinders are connected with the same cross beam, and the other ends are respectively connected with the two upright posts; the two sound pressure sensors are respectively arranged at the front and rear positions of a vehicle; the noise control method comprises the steps that when it is judged that noise is generated by the suspension structure, the pressure value of the hydraulic cylinder is increased till the maximum noise received by the two sound pressure sensors is lower than a preset decibel value. According to the technical scheme, when it is judged that the noise is generated by the suspension structure, the pressure value of the hydraulic cylinder is increased, the rigidity of the suspension structure is enhanced, and therefore the technical effect of reducing the noise generated by the suspension structure is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of vehicle noise control, and in particular to a noise control method, a suspension system and an off-road vehicle. Background Art

[0002] High-end off-road vehicles usually adopt a non-load-bearing body technology solution. The front frame of the body-in-white is far from the A-pillar cantilever. Affected by the curvature of the wheel arch and the shotgun section, the front frame often has a low modal state and is difficult to strengthen. The first suspension installation point adjacent to it is also affected by it, with low dynamic stiffness and difficult to improve, becoming the main risk point for road noise of high-end off-road vehicles. The reinforcement of the front frame is limited by the layout space and weight cost, and the improvement effect is not good.

[0003] The road noise risk caused by the front end and the first suspension is difficult to resolve on a real vehicle, and the resolution cost is high and the cycle is long, which is a major difficulty in vehicle NVH development. Summary of the invention

[0004] The main purpose of the present invention is to provide a noise control method, a suspension system and an off-road vehicle, and in particular to a noise control method, aiming to improve the noise problem generated by the suspension structure.

[0005] To achieve the above-mentioned purpose, the present invention proposes a noise control method, which is applied to the suspension system of an off-road vehicle, and the suspension system comprises: a suspension structure, two hydraulic cylinders, and two sound pressure sensors; the suspension structure comprises two horizontally extending beams and spaced apart in the vertical direction, and two vertically extending pillars and spaced apart in the horizontal direction, and the vertical pillars are respectively connected to the ends of the two beams on the same side; one end of the two hydraulic cylinders is connected to the same beam, and the other end is respectively connected to the two vertical pillars; the two sound pressure sensors are used to be respectively arranged at the front and rear positions of the vehicle;

[0006] The noise control method comprises:

[0007] When it is determined that the noise is generated by the suspension structure, the pressure value of the hydraulic cylinder is increased until the maximum noise received by the two sound pressure sensors is lower than a preset decibel value.

[0008] In one embodiment, the suspension system further comprises two acceleration sensors, which are arranged on the suspension structure at intervals in the horizontal direction;

[0009] Before the step of increasing the hydraulic cylinder pressure value until the maximum noise received by the two sound pressure sensors is lower than the preset decibel value when determining that the noise is generated by the suspension structure, the method further includes:

[0010] Acquire a noise curve according to the noise received by the two sound pressure sensors, and obtain the noise frequency according to the noise curve;

[0011] Acquire an acceleration admittance curve according to the acceleration sensor, and obtain an excitation frequency according to the acceleration admittance curve;

[0012] comparing the noise frequency with the excitation frequency;

[0013] When the difference between the noise frequency and the excitation frequency is within a rated range, it is determined that the noise is generated by the suspension structure;

[0014] When the difference between the noise frequency and the excitation frequency exceeds a rated range, it is determined that the noise is generated by other structures.

[0015] In one embodiment, before the step of obtaining a noise curve according to the noise received by the two sound pressure sensors and obtaining the noise frequency according to the noise curve, the step further includes:

[0016] Determine whether noise is present.

[0017] In one embodiment, the step of determining whether there is noise comprises:

[0018] Respectively obtaining the maximum decibel values ​​received by the two sound pressure sensors;

[0019] When one of the maximum decibel values ​​received by the two sound pressure sensors is greater than the preset decibel value, it is determined that noise exists at the corresponding sound pressure sensor;

[0020] When the maximum decibel values ​​received by the two sound pressure sensors are both less than or equal to the preset decibel value, the sound is determined to be normal.

[0021] In one embodiment, when determining that the noise is generated by the suspension structure, the step of increasing the hydraulic cylinder pressure value until the maximum noise received by the two sound pressure sensors is lower than the preset decibel value further includes:

[0022] The pressure of the pressure cylinder is adjusted according to the maximum acceleration value obtained by the two acceleration sensors.

[0023] In one embodiment, the step of adjusting the pressure of the pressure cylinder according to the maximum acceleration value obtained by the two acceleration sensors comprises:

[0024] When the maximum acceleration value is greater than the preset acceleration value, the two hydraulic cylinders are configured to the first preset pressure value;

[0025] When the maximum acceleration value is less than or equal to the preset acceleration value, the two hydraulic cylinders are configured to the second preset pressure value;

[0026] Wherein, the first preset pressure value is greater than the second preset pressure value.

[0027] In one embodiment, when it is determined that the noise is generated by the suspension structure, the step of increasing the hydraulic cylinder pressure value until the maximum noise received by the two sound pressure sensors is lower than a preset decibel value comprises:

[0028] The pressure values ​​of the two hydraulic cylinders are increased synchronously and the pressure values ​​of the two hydraulic cylinders are kept comparable.

[0029] The present invention also proposes a suspension system, which includes: a suspension structure, two hydraulic cylinders, two sound pressure sensors and two acceleration sensors; the suspension structure has two beams extending in the horizontal direction and spaced apart in the vertical direction, and two columns extending in the vertical direction and spaced apart in the horizontal direction, and the columns are respectively connected to the ends of the two beams on the same side; one end of the two hydraulic cylinders is connected to the same beam, and the other end is respectively connected to the two columns; the two sound pressure sensors are used to be respectively arranged in the front and rear positions of the vehicle; the two acceleration sensors are arranged in the suspension structure at intervals in the horizontal direction.

[0030] In one embodiment, the suspension system also includes a control device, which is communicatively connected to the two sound pressure sensors, the two acceleration sensors, and electrically connected to the two hydraulic cylinders; the control device and a noise control program for the suspension system stored on the control device and executable on the control device, wherein the noise control program for the suspension system is configured as steps of a noise control method.

[0031] The present invention also provides an off-road vehicle, which comprises a suspension system.

[0032] The technical solution of the present invention adjusts the stiffness of the suspension structure by adjusting the pressure of the hydraulic cylinder. The greater the stiffness of the suspension structure, the less likely it is to generate noise or the smaller the noise generated. Two sound pressure sensors are respectively arranged in the front and rear positions of the vehicle. When it is detected that noise can be heard in the front or rear positions of the vehicle, the stiffness of the suspension structure is adjusted by the hydraulic cylinder, thereby reducing the noise generated by the suspension structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention 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 some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0034] Figure 1 A schematic structural diagram of an embodiment of a suspension system provided by the present invention;

[0035] Figure 2 A schematic flow chart of a first embodiment of a noise control method provided by the present invention;

[0036] Figure 3 A schematic flow chart of a second embodiment of the noise control method provided by the present invention;

[0037] Figure 4 A schematic flow chart of a third embodiment of the noise control method provided by the present invention;

[0038] Figure 5 A schematic flow chart of a fourth embodiment of the noise control method provided by the present invention;

[0039] Figure 6 A schematic flow chart of a fifth embodiment of the noise control method provided by the present invention;

[0040] Figure 7 A schematic flow chart of a sixth embodiment of the noise control method provided by the present invention;

[0041] Figure 8 This is a flow chart of the seventh embodiment of the noise control method provided by the present invention.

[0042] Description of Figure Numbers:

[0043] 100. Suspension system; 1. Suspension structure; 11. Crossbeam; 12. Column; 2. Hydraulic cylinder.

[0044] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0047] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0048] High-end off-road vehicles usually adopt a non-load-bearing body technology solution. The front frame of the body-in-white is long from the A-pillar cantilever. Affected by the curvature of the wheel arch and the shotgun section, the front frame often has a low modal state and is difficult to strengthen. The first suspension installation point adjacent to it is also affected by it, and the dynamic stiffness is low and difficult to improve, becoming the main risk point for road noise of high-end off-road vehicles. The reinforcement of the front frame is restricted by the layout space and weight cost, and the improvement effect is not good. The road noise risk caused by the front end and the first suspension is difficult to solve on the actual vehicle, and the high cost and long cycle have become a major difficulty in the development of vehicle NVH.

[0049] The invention provides a noise control method.

[0050] See also Figure 1 to Figure 2 In one embodiment of the present invention, the noise control method is applied to an off-road vehicle suspension system 100, the suspension system 100 comprising: a suspension structure 1, two hydraulic cylinders 2, and two sound pressure sensors; the suspension structure 1 has two horizontally extending beams 11 spaced apart in the vertical direction, and two vertically extending pillars 12 spaced apart in the horizontal direction, the pillars 12 are respectively connected to the ends of the two horizontal beams 11 on the same side; this is the suspension structure 1 in the prior art, on this basis, the two hydraulic cylinders 2 have one end connected to the same horizontal beam 11, and the other end connected to the two vertical pillars 12; the stiffness of the suspension structure 1 is adjusted by adjusting the pressure of the hydraulic cylinder 2, the greater the stiffness of the suspension structure 1, the less likely it is to generate noise or the less noise it generates, the two sound pressure sensors are respectively arranged at the front row and the rear row of the vehicle, when it is detected that noise can be heard at the front row or the rear row of the vehicle, the stiffness of the suspension structure 1 is adjusted by the hydraulic cylinder 2. The technical solution of the present invention increases the pressure value of the hydraulic cylinder 2 when it is determined that the noise is generated by the suspension structure 1, thereby enhancing the rigidity of the suspension structure 1 and reducing the noise generated by the suspension structure 1.

[0051] The steps of the noise control method of the suspension system 100 are as follows: Figure 2 , Figure 2 It is a flow chart of a first embodiment of a noise control method of the present invention.

[0052] The noise control method comprises:

[0053] S3: When it is determined that the noise is generated by the suspension structure 1, the pressure value of the hydraulic cylinder 2 is increased until the maximum noise received by the two sound pressure sensors is lower than a preset decibel value.

[0054] From the above steps, it can be seen that before adjusting the stiffness of the suspension structure by adjusting the pressure value of the hydraulic cylinder 2, the sound can be detected at the front and rear seats of the vehicle, and after determining that the sound is noise, the stiffness of the suspension structure is adjusted so that the maximum noise received by the sound pressure sensor is lower than the preset decibel value.

[0055] During the operation of the vehicle, many transmission parts are in motion and are subject to road bumps, so the sources of noise are multifaceted. Only when the noise is generated by the suspension structure 1, the noise can be eliminated by adjusting the suspension structure 1. Therefore, it is necessary to determine the source of the noise.

[0056] The steps of the noise control method of the suspension system 100 are as follows: Figure 3 , Figure 3 FIG. 4 is a flow chart of a second embodiment of a noise control method according to the present invention.

[0057] The suspension system 100 further includes two acceleration sensors, which are arranged on the suspension structure 1 at intervals in the horizontal direction;

[0058] Before the step of increasing the pressure value of the hydraulic cylinder 2 until the maximum noise received by the two sound pressure sensors is lower than the preset decibel value when determining that the noise is generated by the suspension structure 1, the method further includes:

[0059] S21: acquiring a noise curve according to the noise received by the two sound pressure sensors, and obtaining a noise frequency according to the noise curve;

[0060] S22: acquiring an acceleration admittance curve according to the acceleration sensor, and obtaining an excitation frequency according to the acceleration admittance curve;

[0061] S23: comparing the noise frequency with the excitation frequency;

[0062] S241: When the difference between the noise frequency and the excitation frequency is within a rated range, it is determined that the noise is generated by the suspension structure 1;

[0063] S242: When the difference between the noise frequency and the excitation frequency exceeds a rated range, it is determined that the noise is generated by other structures.

[0064] By comparing the noise frequency with the excitation frequency, it can be determined whether the noise source is generated by the suspension structure 1.

[0065] It is normal for a vehicle to produce certain sounds during operation, but it does not mean that all sounds are noise. Only when the sound is greater than a certain decibel will it be judged as noise.

[0066] The steps of the noise control method of the suspension system 100 are as follows: Figure 4 , Figure 4 It is a flow chart of a third embodiment of a noise control method of the present invention.

[0067] Before the step of obtaining a noise curve according to the noise received by the two sound pressure sensors and obtaining the noise frequency according to the noise curve, the method further includes:

[0068] S1: Determine whether there is noise.

[0069] The loudness of the same sound source heard at different positions inside the vehicle is different due to the different distances, so two sound pressure sensors are used to be respectively set at the front and rear positions of the vehicle to detect the loudness of the sound that can be heard at the front or rear position of the vehicle.

[0070] The steps of the noise control method of the suspension system 100 are as follows: Figure 5 , Figure 5 FIG. 4 is a flow chart of a noise control method according to a fourth embodiment of the present invention.

[0071] The step of determining whether there is noise comprises:

[0072] S11: respectively obtaining the maximum decibel values ​​received by the two sound pressure sensors;

[0073] S121: When one of the maximum decibel values ​​received by the two sound pressure sensors is greater than the preset decibel value, it is determined that noise exists at the corresponding sound pressure sensor;

[0074] S122: When the maximum decibel values ​​received by the two sound pressure sensors are both less than or equal to the preset decibel value, it is determined that the sound is normal.

[0075] When one of the two sound pressure sensors detects the presence of noise, the stiffness of the suspension structure needs to be adjusted.

[0076] Because the suspension structure 1 is subjected to different forces at different locations during its movement, multiple acceleration sensors are provided. In this embodiment, two acceleration sensors are provided. The greater the acceleration detected by the acceleration sensor, the greater the corresponding force, and the more obvious the noise generated.

[0077] The steps of the noise control method of the suspension system 100 are as follows: Figure 6 , Figure 6 FIG. 5 is a flow chart of a fifth embodiment of a noise control method according to the present invention.

[0078] After the step of increasing the pressure value of the hydraulic cylinder 2 until the maximum noise received by the two sound pressure sensors is lower than the preset decibel value when determining that the noise is generated by the suspension structure 1, the method further includes:

[0079] S31: adjusting the pressure of the pressure cylinder according to the maximum acceleration value obtained by the two acceleration sensors.

[0080] The steps of the noise control method of the suspension system 100 are as follows: Figure 7 , Figure 7 It is a flow chart of a sixth embodiment of a noise control method of the present invention.

[0081] Specifically, the step of adjusting the pressure of the pressure cylinder according to the maximum acceleration value obtained by the two acceleration sensors includes:

[0082] S311: When the maximum acceleration value is greater than the preset acceleration value, the two hydraulic cylinders 2 are configured to be the first preset pressure value;

[0083] S312: When the maximum acceleration value is less than or equal to the preset acceleration value, the two hydraulic cylinders 2 are configured to the second preset pressure value;

[0084] Wherein, the first preset pressure value is greater than the second preset pressure value.

[0085] The preset acceleration value may be set to be multiple, that is, according to the maximum acceleration value at different gears, the hydraulic cylinder 2 is adjusted to different pressure values, and the suspension structure 1 is adjusted to different stiffnesses.

[0086] Since two hydraulic cylinders 2 are arranged on the suspension structure 1, in order to make the rigidity of the suspension structure 1 symmetrical, the stability of the overall structure of the vehicle is guaranteed.

[0087] The steps of the noise control method of the suspension system 100 are as follows: Figure 8 , Figure 8 FIG. 4 is a flow chart of a seventh embodiment of a noise control method according to the present invention.

[0088] When it is determined that the noise is generated by the suspension structure 1, the step of increasing the pressure value of the hydraulic cylinder 2 until the maximum noise received by the two sound pressure sensors is lower than the preset decibel value comprises:

[0089] S32: Synchronously increase the pressure values ​​of the two hydraulic cylinders 2 and keep the pressure values ​​of the two hydraulic cylinders 2 equivalent.

[0090] When the pressure values ​​of the two hydraulic cylinders 2 are adjusted synchronously and kept consistent, the structure has better stability.

[0091] The present invention also proposes a suspension system 100, which includes: a suspension structure 1, two hydraulic cylinders 2, two sound pressure sensors and two acceleration sensors; the suspension structure 1 has two beams 11 extending in the horizontal direction and spaced apart in the vertical direction, and two columns 12 extending in the vertical direction and spaced apart in the horizontal direction, and the columns 12 are respectively connected to the ends of the two beams 11 on the same side; one end of the two hydraulic cylinders 2 is connected to the same beam 11, and the other end is respectively connected to the two columns 12; the two sound pressure sensors are used to be respectively arranged in the front and rear positions of the vehicle; the two acceleration sensors are arranged in the suspension structure 1 at intervals in the horizontal direction.

[0092] The suspension system 100 also includes a control device, which is respectively communicatively connected to the two sound pressure sensors, the two acceleration sensors, and electrically connected to the two hydraulic cylinders 2; the control device and a noise control program for the suspension system 100 stored on the control device and capable of running on the control device, wherein the noise control program of the suspension system 100 is configured as steps of a noise control method.

[0093] The present invention also proposes an off-road vehicle, which includes a suspension system 100. The specific structure and control method of the suspension system 100 refer to the above-mentioned embodiments. Since the off-road vehicle adopts all the technical solutions of all the above-mentioned embodiments, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.

[0094] Among them, the existing off-road vehicles have multiple suspension structures 1, and improvements can be made on different suspension structures 1 according to the above suspension system, so that the noise at the suspension structures 1 in various parts of the vehicle can be monitored. In particular, the first suspension structure at the front end of the off-road vehicle is relatively long from the A-pillar cantilever. Affected by the curvature of the wheel cover and the shotgun cross section, the front frame often has a low modal state and is difficult to strengthen. The first suspension installation point adjacent to it is also affected by it, and the dynamic stiffness is low and difficult to improve, becoming the main risk point for road noise of high-end off-road vehicles. By making improvements according to the above suspension system, not only is the structure simple, but the transformation cost is low, the development cycle is short, and it is also easy to maintain later.

[0095] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A noise control method, applied to an off-road vehicle suspension system, characterized in that: The suspension system comprises: The suspension structure comprises two horizontal beams extending in the horizontal direction and spaced apart in the vertical direction, and two vertical columns extending in the vertical direction and spaced apart in the horizontal direction, wherein the vertical columns are respectively connected to the ends of the two horizontal beams on the same side; Two hydraulic cylinders, one end of the two hydraulic cylinders is connected to the same crossbeam, and the other end is connected to the two columns respectively; Two sound pressure sensors are respectively arranged at the front and rear seats of the vehicle; The noise control method comprises: When it is determined that the noise is generated by the suspension structure, the pressure value of the hydraulic cylinder is increased until the maximum noise received by the two sound pressure sensors is lower than a preset decibel value.

2. The noise control method according to claim 1, characterized in that: The suspension system further comprises two acceleration sensors which are arranged on the suspension structure at intervals in the horizontal direction; Before the step of increasing the hydraulic cylinder pressure value until the maximum noise received by the two sound pressure sensors is lower than the preset decibel value when determining that the noise is generated by the suspension structure, the method further includes: Acquire a noise curve according to the noise received by the two sound pressure sensors, and obtain the noise frequency according to the noise curve; Acquire an acceleration admittance curve according to the acceleration sensor, and obtain an excitation frequency according to the acceleration admittance curve; comparing the noise frequency with the excitation frequency; When the difference between the noise frequency and the excitation frequency is within a rated range, it is determined that the noise is generated by the suspension structure; When the difference between the noise frequency and the excitation frequency exceeds a rated range, it is determined that the noise is generated by other structures.

3. The noise control method according to claim 2, characterized in that: Before the step of obtaining a noise curve according to the noise received by the two sound pressure sensors and obtaining the noise frequency according to the noise curve, the method further includes: Determine whether noise is present.

4. The noise control method according to claim 3, characterized in that: The step of determining whether there is noise comprises: Respectively obtaining the maximum decibel values ​​received by the two sound pressure sensors; When one of the maximum decibel values ​​received by the two sound pressure sensors is greater than the preset decibel value, it is determined that noise exists at the corresponding sound pressure sensor; When the maximum decibel values ​​received by the two sound pressure sensors are both less than or equal to the preset decibel value, the sound is determined to be normal.

5. The noise control method according to claim 1, characterized in that: After the step of increasing the hydraulic cylinder pressure value until the maximum noise received by the two sound pressure sensors is lower than the preset decibel value when determining that the noise is generated by the suspension structure, the method further includes: The pressure of the pressure cylinder is adjusted according to the maximum acceleration value obtained by the two acceleration sensors.

6. The noise control method according to claim 5, characterized in that: The step of adjusting the pressure of the pressure cylinder according to the maximum acceleration value obtained by the two acceleration sensors comprises: When the maximum acceleration value is greater than the preset acceleration value, the two hydraulic cylinders are configured to the first preset pressure value; When the maximum acceleration value is less than or equal to the preset acceleration value, the two hydraulic cylinders are configured to the second preset pressure value; Wherein, the first preset pressure value is greater than the second preset pressure value.

7. The noise control method according to claim 1, characterized in that: When it is determined that the noise is generated by the suspension structure, the step of increasing the pressure value of the hydraulic cylinder until the maximum noise received by the two sound pressure sensors is lower than the preset decibel value comprises: The pressure values ​​of the two hydraulic cylinders are increased synchronously and the pressure values ​​of the two hydraulic cylinders are kept comparable.

8. A suspension system, characterized in that: The suspension system comprises: The suspension structure comprises two horizontal beams extending in the horizontal direction and spaced apart in the vertical direction, and two vertical columns extending in the vertical direction and spaced apart in the horizontal direction, wherein the vertical columns are respectively connected to the ends of the two horizontal beams on the same side; Two hydraulic cylinders, one end of the two hydraulic cylinders is connected to the same crossbeam, and the other end is connected to the two columns respectively; Two sound pressure sensors are respectively arranged at the front and rear seats of the vehicle; Two acceleration sensors are arranged on the suspension structure at intervals along the horizontal direction.

9. The suspension system according to claim 8, characterized in that: The suspension system also includes a control device, which is communicatively connected to the two sound pressure sensors, the two acceleration sensors, and electrically connected to the two hydraulic cylinders; the control device and a noise control program for the suspension system stored on the control device and executable on the control device, wherein the noise control program for the suspension system is configured to implement the steps of the noise control method as described in any one of claims 1 to 7.

10. An off-road vehicle, characterized in that: The off-road vehicle includes the suspension system of claim 9.

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