Method and device for controlling semi-active suspension

Abstract

The invention provides a control method and device of a semi-active suspension, which are applied to a semi-active suspension controller in a vehicle and are used for acquiring vehicle body parameters and suspension parameters in a forward driving process of the vehicle in real time, the vehicle body parameters comprise parameters representing a vehicle body vertical motion state of a front axle part of the vehicle, and the suspension parameters comprise parameters representing a vehicle body vertical motion state of the front axle part of the vehicle. The suspension parameters comprise parameters representing the suspension vertical motion state of the front axle part of the vehicle, estimating the vibration state of the front axle of the vehicle based on the vehicle body parameters and the suspension parameters to obtain front axle vibration parameters, and when the front axle vibration parameters are larger than or equal to a control threshold value, controlling the front axle part of the vehicle. And a control quantity is obtained according to the current target vehicle speed of the vehicle, the vibration parameters of the front axle and a preset function relation, and a semi-active suspension of the vehicle is controlled to adjust damping of an adjustable shock absorber of the rear axle based on the control quantity. According to the scheme, the rear axle control mode is achieved according to the front axle response, the situation that the control effect of the semi-active suspension is affected due to delay is avoided, and the control robustness of the semi-active suspension is further improved.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile electronics, and in particular to a control method and device for a semi-active suspension. Background Art

[0002] When a vehicle is driving on a bumpy road or passing through a speed bump, it will shake violently, affecting the driving and riding comfort of the vehicle. To address the above problems, vehicles equipped with semi-automatic suspension can adjust the damping of the adjustable shock absorber by controlling the semi-automatic suspension to ensure the stability of the vehicle when passing through potholes, speed bumps and other roads with obstacles.

[0003] The existing control method of semi-active suspension is to use the corresponding sensor information of the front and rear axles to realize the corresponding axle control. This method has delays, which affects the control effect of the semi-active suspension. For example, when the rear axle passes over a speed bump, if only the signal of the rear axle sensor is used to control the rear axle shock absorber, it cannot be guaranteed that the rear axle is still on the speed bump when the control is performed. Summary of the invention

[0004] In view of this, an embodiment of the present invention provides a control method and device for a semi-active suspension, so as to avoid the situation where delay affects the control effect of the semi-active suspension and increase the robustness of the control of the semi-active suspension.

[0005] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0006] A first aspect of an embodiment of the present invention discloses a control method for a semi-active suspension, which is applied to a semi-active suspension controller in a vehicle. The method comprises:

[0007] Acquiring in real time the body parameters and suspension parameters of the vehicle during the forward movement of the vehicle; the body parameters include: parameters characterizing the vertical motion state of the body of the front axle portion of the vehicle, and the suspension parameters include: parameters characterizing the vertical motion state of the suspension of the front axle portion of the vehicle;

[0008] estimating a vibration state of a front axle of the vehicle based on the vehicle body parameters and the suspension parameters to obtain front axle vibration parameters;

[0009] When the front axle vibration parameter is greater than or equal to a control threshold, obtaining the current speed of the vehicle to obtain a target speed, and obtaining a control amount according to the target speed, the front axle vibration parameter and a preset functional relationship;

[0010] The semi-active suspension of the vehicle is controlled to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount.

[0011] Preferably, estimating the vibration state of the front axle of the vehicle based on the vehicle body parameters and the suspension parameters to obtain the front axle vibration parameters includes:

[0012] Acquire a current driving mode of the vehicle set by a user, and acquire a corresponding vehicle body vibration estimation coefficient and a suspension vibration estimation coefficient according to the driving mode;

[0013] A sum of a product of the vehicle body parameter multiplied by the vehicle body vibration estimation coefficient and a product of the suspension parameter multiplied by the suspension vibration estimation coefficient is calculated to obtain a front axle vibration parameter.

[0014] Preferably, after controlling the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount, the method further comprises:

[0015] It is determined whether the travel distance of the vehicle is greater than the wheelbase of the vehicle. If so, the control of the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle is stopped.

[0016] Preferably, the determining whether the travel distance of the vehicle is greater than the wheelbase of the vehicle, and if so, stopping controlling the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle includes:

[0017] After each preset control cycle, an average speed of the vehicle in the control cycle is obtained;

[0018] Based on the average vehicle speed and the control period, calculating the travel distance of the vehicle within the control period;

[0019] Add the driving distance to the historical driving distance in each previous control cycle to obtain the total driving distance;

[0020] Determining whether the total driving distance is greater than the wheelbase of the vehicle;

[0021] If so, the control of the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle is stopped.

[0022] Preferably, after controlling the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount, the method further comprises:

[0023] After each preset control cycle, an average speed of the vehicle in the control cycle is obtained;

[0024] If the average vehicle speed is not equal to the target vehicle speed, updating the target vehicle speed based on the average vehicle speed;

[0025] updating the control amount according to the updated target vehicle speed, the front axle vibration parameter and a preset functional relationship;

[0026] Based on the updated control quantity, the semi-active suspension of the vehicle is controlled to adjust the damping of the adjustable shock absorber of the rear axle, and the step of obtaining the average vehicle speed of the vehicle during the control cycle after each preset control cycle is returned to be executed.

[0027] A second aspect of an embodiment of the present invention discloses a control device for a semi-active suspension, which is applied to a semi-active suspension controller in a vehicle. The device comprises:

[0028] an acquisition unit, for acquiring in real time body parameters and suspension parameters of the vehicle during the forward movement of the vehicle; the body parameters include parameters characterizing the vertical motion state of the body of the front axle portion of the vehicle, and the suspension parameters include parameters characterizing the vertical motion state of the suspension of the front axle portion of the vehicle;

[0029] an estimating unit, configured to estimate a vibration state of a front axle of the vehicle based on the vehicle body parameters and the suspension parameters, and obtain a front axle vibration parameter;

[0030] a calculation unit, configured to obtain a current speed of the vehicle to obtain a target speed when the front axle vibration parameter is greater than or equal to a control threshold, and obtain a control amount according to the target speed, the front axle vibration parameter and a preset functional relationship;

[0031] A control unit is used to control the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount.

[0032] Preferably, the estimation unit is specifically used for:

[0033] Acquire a current driving mode of the vehicle set by a user, and acquire a corresponding vehicle body vibration estimation coefficient and a suspension vibration estimation coefficient according to the driving mode;

[0034] A sum of a product of the vehicle body parameter multiplied by the vehicle body vibration estimation coefficient and a product of the suspension parameter multiplied by the suspension vibration estimation coefficient is calculated to obtain a front axle vibration parameter.

[0035] Preferably, the device further comprises:

[0036] a judging unit, configured to judge whether a travel distance of the vehicle is greater than a wheelbase of the vehicle after the semi-active suspension of the vehicle is controlled to adjust the damping of an adjustable shock absorber of a rear axle based on the control amount;

[0037] If so, the control of the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle is stopped.

[0038] Preferably, the judging unit comprises:

[0039] An acquisition subunit, used for acquiring an average speed of the vehicle in a preset control cycle after each control cycle;

[0040] A calculation subunit, configured to calculate the travel distance of the vehicle within the control period based on the average vehicle speed and the control period; and add the travel distance to the historical travel distances within each previous control period to obtain a total travel distance;

[0041] The judging subunit is used to judge whether the total driving distance is greater than the wheelbase of the vehicle; if so, stop controlling the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle.

[0042] Preferably, the device further comprises:

[0043] An updating unit is used for, after the semi-active suspension of the vehicle is controlled to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount, obtaining the average vehicle speed of the vehicle during each preset control cycle; if the average vehicle speed is not equal to the target vehicle speed, updating the target vehicle speed based on the average vehicle speed; updating the control amount according to the updated target vehicle speed, the front axle vibration parameter and a preset functional relationship; based on the updated control amount, controlling the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle, and returning to execute the step of obtaining the average vehicle speed of the vehicle during the control cycle after each preset control cycle.

[0044] Based on the above-mentioned embodiment of the present invention, a control method and device for a semi-active suspension is provided, which is applied to a semi-active suspension controller in a vehicle, and the method includes: obtaining the body parameters and suspension parameters of the vehicle in real time during the forward driving process; the body parameters include: parameters characterizing the vertical motion state of the body of the front axle part of the vehicle, and the suspension parameters include: parameters characterizing the vertical motion state of the suspension of the front axle part of the vehicle; based on the body parameters and the suspension parameters, the vibration state of the front axle of the vehicle is estimated to obtain the front axle vibration parameters; when the front axle vibration parameters are greater than or equal to the control threshold, the control amount is obtained according to the current target speed of the vehicle, the front axle vibration parameters and the preset functional relationship; based on the control amount, the semi-active suspension of the vehicle is controlled to adjust the damping of the adjustable shock absorber of the rear axle. In this scheme, the method of realizing rear axle control according to the front axle response not only avoids the situation where the delay affects the control effect of the semi-active suspension, but also increases the robustness of the control of the semi-active suspension. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] 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 embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0046] Figure 1 A flow chart of a control method for a semi-active suspension disclosed in an embodiment of the present invention;

[0047] Figure 2 The present invention is a structural diagram of a control device for a semi-active suspension disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0048] 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.

[0049] In this application, the terms "comprises", "comprising" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising 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 sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0050] As can be seen from the background technology, the existing control method of semi-active suspension is to use the corresponding sensor information of the front axle and the rear axle to realize the corresponding axle control. This method has a delay, which affects the control effect of the semi-active suspension. For example, when the rear axle passes over a speed bump, if only the signal of the rear axle sensor is used to control the rear axle shock absorber, it cannot be guaranteed that the rear axle is still on the speed bump when the control is performed.

[0051] Therefore, an embodiment of the present invention discloses a control method and device for a semi-active suspension. In this solution, the rear axle control is implemented according to the front axle response, which not only avoids the situation where the delay affects the control effect of the semi-active suspension, but also increases the robustness of the control of the semi-active suspension.

[0052] like Figure 1FIG. 1 is a flow chart of a control method for a semi-active suspension disclosed in an embodiment of the present invention. The method is applied to a semi-active suspension controller in a vehicle and mainly includes the following steps:

[0053] Step S101: acquiring body parameters and suspension parameters of the vehicle in real time during the forward driving process.

[0054] In step S101 , the vehicle body parameters include: parameters characterizing the vertical motion state of the vehicle body at the front axle portion of the vehicle, and the suspension parameters include: parameters characterizing the vertical motion state of the suspension at the front axle portion of the vehicle.

[0055] It should be noted that the vehicle's front and rear axles both have body sensors and suspension sensors connected to the semi-active suspension controller. The body sensors on the front and rear axles are respectively used to collect the vertical acceleration or vertical speed of the front and rear axle parts of the body and other parameters that can characterize the vertical motion state of the body. The suspension sensors on the front and rear axles are respectively used to collect the vertical motion speed or vertical displacement of the front and rear axle parts of the suspension and other parameters that can characterize the vertical motion state of the suspension.

[0056] It should also be noted that the present application realizes rear axle control based on the front axle response, that is, through the body parameters and suspension parameters of the front axle, it is judged whether the front axle passes through an obstacle, and the rear axle is controlled before the rear axle passes through the obstacle, that is, the semi-active suspension is controlled to adjust the damping of the adjustable shock absorber of the rear axle, so that the rear axle passes the obstacle smoothly, so the vehicle needs to be in a forward driving state.

[0057] Step S102: Based on the vehicle body parameters and suspension parameters, the vibration state of the front axle of the vehicle is estimated to obtain the front axle vibration parameters.

[0058] In the specific implementation process of step S102, the current driving mode of the vehicle set by the user is obtained, and the corresponding vehicle body vibration estimation coefficient and suspension vibration estimation coefficient are obtained according to the driving mode.

[0059] Specifically, the driving mode signal M is acquired through the vehicle's onboard system, and the driving mode of the vehicle is determined based on the driving mode signal M.

[0060] For example, comfort mode M=1, standard mode M=2, and sports mode M=3.

[0061] Each driving mode is pre-set with a corresponding vehicle body vibration estimation coefficient and suspension vibration estimation coefficient.

[0062] Specifically, the vehicle body vibration estimation coefficient and the suspension vibration estimation coefficient can be determined according to the driving mode signal M, as shown in the following formula:

[0063]

[0064] Among them, α is the estimated coefficient of body vibration, β is the estimated coefficient of suspension vibration, and M is the driving mode signal. In comfort mode, M=1, α and β are α1, β1 respectively; in standard mode, M=2, α and β are α2, β2 respectively; in sports mode, M=3, α and β are α3, β3 respectively.

[0065] It should be noted that the vibration state of the front axle is judged differently in different driving modes set by the user.

[0066] For example, in comfort mode, more emphasis is placed on suppressing vehicle body vibration. Therefore, the vehicle body vibration estimation coefficient and suspension vibration estimation coefficient corresponding to the comfort mode are larger, so that the calculated front axle vibration parameters are larger, and it is easier to enter a state of controlling the rear axle.

[0067] In contrast, the sports mode pays more attention to road feel and grip. Therefore, the body vibration estimation coefficient and suspension vibration estimation coefficient corresponding to the sports mode are smaller, so that the calculated front axle vibration parameters are smaller, and it is more difficult to enter the state of controlling the rear axle.

[0068] The front axle vibration parameter is obtained by calculating the sum of the product of the vehicle body parameter multiplied by the vehicle body vibration estimation coefficient and the product of the suspension parameter multiplied by the suspension vibration estimation coefficient. The calculation formula is as follows:

[0069] Q = α × A + β × P

[0070] Among them, Q is the front axle vibration parameter, α is the body vibration estimation coefficient, β is the suspension vibration estimation coefficient, A is the body parameter, and P is the suspension parameter.

[0071] Step S103: When the front axle vibration parameter is greater than or equal to the control threshold, the current vehicle speed is obtained to obtain the target vehicle speed, and the control amount is obtained according to the target vehicle speed, the front axle vibration parameter and a preset functional relationship.

[0072] In step S103 , the target vehicle speed is obtained through the vehicle's ESP (Electronic Stability Program) system, ie, the electronic stability program.

[0073] The control threshold is a pre-calibrated value obtained through actual vehicle testing. The front axle vibration parameters are compared with the control threshold as shown in the following formula:

[0074]

[0075] Among them, S is the controller state, 1 means that the pulse vibration control of the semi-automatic suspension needs to be turned on, and the damping of the rear axle adjustable shock absorber needs to be adjusted, and the corresponding 0 means that it does not need to be turned on, Q Thres To control the threshold.

[0076] In the specific implementation process of step S103, the output control amount E is determined according to the controller state S. When the pulse vibration state is S=0, it means that the behavior does not need to be controlled, so the output is 0. E is determined by the target vehicle speed V and the vibration state, that is, the front axle vibration parameter Q. That is, E is a function of the target vehicle speed V and the vibration state Q, as shown in the following formula:

[0077]

[0078] It should be noted that the control quantity in the present invention is ultimately related to the parameters obtained by the body sensors and suspension sensors corresponding to the front axle. Therefore, when the body sensors and suspension sensors corresponding to the rear axle fail, the semi-active suspension can still be controlled, and then the adjustable shock absorber damping of the rear axle can be adjusted. This method of controlling the rear axle based on the response of the front axle can increase the robustness of the system.

[0079] Step S104: Controlling the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount.

[0080] In the specific implementation process of step S104, a pulse vibration control signal is generated based on the control amount and sent to the semi-active suspension, and pulse vibration control is performed on the semi-active suspension of the vehicle, thereby adjusting the damping of the adjustable shock absorber of the rear axle.

[0081] In one embodiment, after step S104, it is also necessary to determine whether to exit the pulse vibration control, that is, to stop controlling the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle. Generally speaking, the pulse vibration control can be exited after the rear axle passes an obstacle.

[0082] Since the pulse vibration control is triggered by the front axle wheel end passing an obstacle, it is determined whether the vehicle's driving distance is greater than the vehicle's wheelbase. If so, the pulse vibration control is exited, that is, the control of the vehicle's semi-active suspension to adjust the damping of the adjustable shock absorber on the rear axle is stopped.

[0083] The specific process of judging whether the driving distance of the vehicle is greater than the wheelbase of the vehicle is as follows:

[0084] After each preset control cycle, the average speed of the vehicle during the control cycle is obtained. Based on the average speed and the control cycle, the driving distance of the vehicle during the control cycle is calculated. The driving distance is added to the historical driving distance in the past control cycles to obtain the total driving distance.

[0085] It is determined whether the total driving distance is greater than the wheelbase of the vehicle. If so, the control of the semi-active suspension of the vehicle is stopped to adjust the damping of the adjustable shock absorber of the rear axle.

[0086] The above judgment process is expressed as follows:

[0087]

[0088] Among them, S is the controller state, 1 means that the pulse vibration control of the semi-automatic suspension needs to be turned on and the damping of the rear axle adjustable shock absorber needs to be adjusted, and the corresponding 0 means that it does not need to be turned on, V k is the average vehicle speed in the kth control cycle, n is the number of past control cycles, L is the wheelbase of the vehicle, and T is the control cycle.

[0089] In the embodiment of the present invention, a judgment is made whether to exit the pulse vibration control every time a preset control cycle passes, so that the adjustable shock absorber on the rear axle of the vehicle can restore normal damping in time to ensure the comfort of the vehicle.

[0090] In one embodiment, after the front axle of the vehicle passes the obstacle and during the period before the rear axle passes the obstacle, the vehicle may decelerate, including the driver's active deceleration. At this time, the control amount is updated according to the real-time vehicle speed, as follows:

[0091] Step S11: After each preset control cycle, the average speed of the vehicle in the control cycle is obtained.

[0092] Step S12: If the average vehicle speed is not equal to the target vehicle speed, the target vehicle speed is updated based on the average vehicle speed, and the control amount is updated according to the updated target vehicle speed, the front axle vibration parameter and the preset functional relationship.

[0093] Step S13: Based on the updated control amount, control the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle, and return to execute step S11.

[0094] Based on the control method of a semi-active suspension disclosed in the above embodiment of the present invention, the semi-active suspension controller in the vehicle is applied, and the method includes: obtaining the body parameters and suspension parameters of the vehicle in the process of moving forward in real time, the body parameters include: parameters characterizing the vertical motion state of the body of the front axle part of the vehicle, and the suspension parameters include: parameters characterizing the vertical motion state of the suspension of the front axle part of the vehicle, estimating the vibration state of the front axle of the vehicle based on the body parameters and the suspension parameters, and obtaining the front axle vibration parameters, when the front axle vibration parameters are greater than or equal to the control threshold, obtaining and obtaining the control amount according to the current target speed of the vehicle, the front axle vibration parameters and the preset functional relationship, and controlling the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount. In this scheme, the method of realizing the rear axle control according to the front axle response not only avoids the situation that the delay affects the control effect of the semi-active suspension, but also increases the robustness of the control of the semi-active suspension.

[0095] Corresponding to the control method of a semi-active suspension disclosed in the above embodiment of the present invention, as Figure 2 FIG. 1 is a structural diagram of a control device for a semi-active suspension disclosed in an embodiment of the present invention. The device is applied to a semi-active suspension controller in a vehicle and mainly includes:

[0096] The acquisition unit 201 is used to acquire the body parameters and suspension parameters of the vehicle in real time during the forward driving process; the body parameters include: parameters characterizing the vertical movement state of the body of the front axle part of the vehicle, and the suspension parameters include: parameters characterizing the vertical movement state of the suspension of the front axle part of the vehicle.

[0097] The estimation unit 202 is used to estimate the vibration state of the front axle of the vehicle based on the vehicle body parameters and the suspension parameters to obtain the front axle vibration parameters.

[0098] The calculation unit 203 is used to obtain the current vehicle speed to obtain the target vehicle speed when the front axle vibration parameter is greater than or equal to the control threshold, and obtain the control amount according to the target vehicle speed, the front axle vibration parameter and a preset functional relationship.

[0099] The control unit 204 is used to control the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount.

[0100] In one embodiment, the estimation unit 202 is specifically configured to:

[0101] Obtaining the current driving mode of the vehicle set by the user, and obtaining the corresponding vehicle body vibration estimation coefficient and suspension vibration estimation coefficient according to the driving mode;

[0102] The sum of the product of the vehicle body parameter multiplied by the vehicle body vibration estimation coefficient and the product of the suspension parameter multiplied by the suspension vibration estimation coefficient is calculated to obtain the front axle vibration parameter.

[0103] In one embodiment, the control device for the semi-active suspension further includes:

[0104] The judging unit is used to judge whether the travel distance of the vehicle is greater than the wheelbase of the vehicle after the semi-active suspension of the vehicle is controlled to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount.

[0105] If so, the semi-active suspension of the vehicle is stopped to adjust the damping of the adjustable shock absorber of the rear axle.

[0106] In one embodiment, the judging unit includes:

[0107] The acquisition subunit is used to acquire the average speed of the vehicle within a preset control cycle every time a preset control cycle passes.

[0108] The calculation subunit is used to calculate the driving distance of the vehicle within the control period based on the average vehicle speed and the control period; and add the driving distance to the historical driving distance in each previous control period to obtain the total driving distance.

[0109] The judging subunit is used to judge whether the total driving distance is greater than the wheelbase of the vehicle; if so, the semi-active suspension of the vehicle is stopped from being controlled to adjust the damping of the adjustable shock absorber of the rear axle.

[0110] In one embodiment, the control device for the semi-active suspension further includes:

[0111] The updating unit is used for, after the semi-active suspension of the vehicle is controlled to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount, obtaining the average vehicle speed of the vehicle in each preset control cycle; if the average vehicle speed is not equal to the target vehicle speed, the target vehicle speed is updated based on the average vehicle speed, and the control amount is updated according to the updated target vehicle speed, the front axle vibration parameter and the preset functional relationship; based on the updated control amount, the semi-active suspension of the vehicle is controlled to adjust the damping of the adjustable shock absorber of the rear axle, and returning to execute the step of obtaining the average vehicle speed of the vehicle in the control cycle after each preset control cycle.

[0112] Based on the control device of a semi-active suspension disclosed in the above embodiment of the present invention, the semi-active suspension controller in the vehicle is applied, and the method includes: obtaining the body parameters and suspension parameters of the vehicle in the process of moving forward in real time, the body parameters include: parameters characterizing the vertical motion state of the body of the front axle part of the vehicle, and the suspension parameters include: parameters characterizing the vertical motion state of the suspension of the front axle part of the vehicle, estimating the vibration state of the front axle of the vehicle based on the body parameters and the suspension parameters, and obtaining the front axle vibration parameters, when the front axle vibration parameters are greater than or equal to the control threshold, obtaining and obtaining the control amount according to the current target speed of the vehicle, the front axle vibration parameters and the preset functional relationship, and controlling the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount. In this scheme, the method of realizing the rear axle control according to the front axle response not only avoids the situation that the delay affects the control effect of the semi-active suspension, but also increases the robustness of the control of the semi-active suspension.

[0113] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can refer to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system or system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiment. The system and system embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without creative work.

[0114] 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 the present invention.

[0115] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A control method for a semi-active suspension, characterized in that: A semi-active suspension controller applied to a vehicle, the method comprising: Acquiring in real time the body parameters and suspension parameters of the vehicle during the forward movement of the vehicle; the body parameters include: parameters characterizing the vertical motion state of the body of the front axle portion of the vehicle, and the suspension parameters include: parameters characterizing the vertical motion state of the suspension of the front axle portion of the vehicle; estimating a vibration state of a front axle of the vehicle based on the vehicle body parameters and the suspension parameters to obtain front axle vibration parameters; When the front axle vibration parameter is greater than or equal to a control threshold, obtaining the current speed of the vehicle to obtain a target speed, and obtaining a control amount according to the target speed, the front axle vibration parameter and a preset functional relationship; The semi-active suspension of the vehicle is controlled to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount.

2. The method according to claim 1, characterized in that The estimating the vibration state of the front axle of the vehicle based on the vehicle body parameters and the suspension parameters to obtain the front axle vibration parameters includes: Acquire a current driving mode of the vehicle set by a user, and acquire a corresponding vehicle body vibration estimation coefficient and a suspension vibration estimation coefficient according to the driving mode; A sum of a product of the vehicle body parameter multiplied by the vehicle body vibration estimation coefficient and a product of the suspension parameter multiplied by the suspension vibration estimation coefficient is calculated to obtain a front axle vibration parameter.

3. The method according to claim 1, characterized in that After controlling the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount, the method further includes: It is determined whether the travel distance of the vehicle is greater than the wheelbase of the vehicle. If so, the control of the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle is stopped.

4. The method according to claim 3, characterized in that The determining whether the travel distance of the vehicle is greater than the wheelbase of the vehicle, and if so, stopping controlling the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle includes: After each preset control cycle, an average speed of the vehicle in the control cycle is obtained; Based on the average vehicle speed and the control period, calculating the travel distance of the vehicle within the control period; Add the driving distance to the historical driving distance in each previous control cycle to obtain the total driving distance; Determining whether the total driving distance is greater than the wheelbase of the vehicle; If so, the control of the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle is stopped.

5. The method according to any one of claims 1 to 4, characterized in that: After controlling the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount, the method further includes: After each preset control cycle, an average speed of the vehicle in the control cycle is obtained; If the average vehicle speed is not equal to the target vehicle speed, updating the target vehicle speed based on the average vehicle speed; updating the control amount according to the updated target vehicle speed, the front axle vibration parameter and a preset functional relationship; Based on the updated control quantity, the semi-active suspension of the vehicle is controlled to adjust the damping of the adjustable shock absorber of the rear axle, and the step of obtaining the average vehicle speed of the vehicle during the control cycle after each preset control cycle is returned to be executed.

6. A control device for a semi-active suspension, characterized in that: A semi-active suspension controller for a vehicle, the device comprising: an acquisition unit, for acquiring in real time body parameters and suspension parameters of the vehicle during the forward movement of the vehicle; the body parameters include parameters characterizing the vertical motion state of the body of the front axle portion of the vehicle, and the suspension parameters include parameters characterizing the vertical motion state of the suspension of the front axle portion of the vehicle; an estimating unit, configured to estimate a vibration state of a front axle of the vehicle based on the vehicle body parameters and the suspension parameters to obtain a front axle vibration parameter; a calculation unit, configured to obtain a current speed of the vehicle to obtain a target speed when the front axle vibration parameter is greater than or equal to a control threshold, and obtain a control amount according to the target speed, the front axle vibration parameter and a preset functional relationship; A control unit is used to control the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount.

7. The device according to claim 6, characterized in that The estimation unit is specifically used for: Acquire a current driving mode of the vehicle set by a user, and acquire a corresponding vehicle body vibration estimation coefficient and a suspension vibration estimation coefficient according to the driving mode; A sum of a product of the vehicle body parameter multiplied by the vehicle body vibration estimation coefficient and a product of the suspension parameter multiplied by the suspension vibration estimation coefficient is calculated to obtain a front axle vibration parameter.

8. The device according to claim 6, characterized in that The device also includes: a judging unit, configured to judge whether a travel distance of the vehicle is greater than a wheelbase of the vehicle after the semi-active suspension of the vehicle is controlled to adjust the damping of an adjustable shock absorber of a rear axle based on the control amount; If so, the control of the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle is stopped.

9. The device according to claim 8, characterized in that The judging unit comprises: An acquisition subunit, used for acquiring an average speed of the vehicle in a preset control cycle after each control cycle; A calculation subunit, configured to calculate the travel distance of the vehicle within the control period based on the average vehicle speed and the control period; and add the travel distance to the historical travel distances within each previous control period to obtain a total travel distance; The judging subunit is used to judge whether the total driving distance is greater than the wheelbase of the vehicle; if so, stop controlling the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle.

10. The device according to any one of claims 6 to 9, characterized in that: The device also includes: An updating unit is used for, after the semi-active suspension of the vehicle is controlled to adjust the damping of the adjustable shock absorber of the rear axle based on the control amount, obtaining the average vehicle speed of the vehicle during each preset control cycle; if the average vehicle speed is not equal to the target vehicle speed, updating the target vehicle speed based on the average vehicle speed; updating the control amount according to the updated target vehicle speed, the front axle vibration parameter and a preset functional relationship; based on the updated control amount, controlling the semi-active suspension of the vehicle to adjust the damping of the adjustable shock absorber of the rear axle, and returning to execute the step of obtaining the average vehicle speed of the vehicle during the control cycle after each preset control cycle.

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