A vehicle height and posture combined adjustment method with active suspension actuator and height adjustment mechanism

Abstract

The application discloses a vehicle height and posture combined adjusting method with active suspension executing mechanism and height adjusting mechanism, relates to the technical field of new energy automobile suspension control, and comprises the following steps: collecting vehicle four-wheel height, vehicle body posture, suspension motion state, active suspension executing mechanism state, height adjusting mechanism state and vehicle motion state; the active suspension executing mechanism serves as a fast executing channel; and the height adjusting mechanism serves as a slow executing channel. Through the fast and slow cooperation of the active suspension and the height adjusting mechanism, the vehicle body height, side inclination and pitching are jointly adjusted, the active suspension static support bias is identified, the unloading and the middle position recovery are realized through the height adjusting mechanism, the posture change caused by the uneven ground is identified at the same time, the forced leveling is avoided to cause the wheel load abnormality or the executing mechanism limitation, and the adjusting coordination, adaptability and operation efficiency are improved.

Description

Technical Field

[0001] This invention relates to the field of suspension control technology for new energy vehicles, specifically to a method for jointly adjusting vehicle height and attitude with an active suspension actuator and a height adjustment mechanism. Background Technology

[0002] With the development of new energy vehicles and their chassis electronic control technology, vehicle suspension has gradually evolved from traditional passive forms to air suspension, hydropneumatic suspension, semi-active suspension, and fully active suspension. The core function of vehicle suspension is to support the vehicle body, isolate road surface excitation, ensure tire contact with the ground, and maintain a reasonable vehicle body posture under conditions such as acceleration, braking, steering, and load changes.

[0003] Among them, height adjustment mechanisms such as air springs and hydraulic cylinders can change the static height of the vehicle body. They have the characteristics of strong load-bearing capacity and are suitable for maintaining the reference support for a long time. However, their response is relatively slow and they are easily affected by factors such as pressure, flow rate and wheel load distribution. Fully active suspension actuators, such as hydraulic, electromechanical or linear motor active suspension actuators, can quickly and actively generate support force or displacement. They have good posture compensation and vibration suppression capabilities, but they are not suitable for bearing large static bias forces for a long time. Otherwise, it will easily cause a reduction in the available stroke of the actuator, an increase in power consumption and temperature rise, and a decrease in reliability.

[0004] Existing vehicle height and attitude joint control technology is mainly aimed at electronically controlled air suspension. By collecting signals such as the height of the four corners of the vehicle, the pitch angle and roll angle of the vehicle, the on / off state of the air suspension solenoid valve is determined according to the vehicle height adjustment strategy. Combined with the overall vehicle attitude control strategy, the inflation and deflation process of the four corner air springs is corrected to improve the problems of excessive pitch and roll angles caused by asynchronous lifting of the four corners during the height adjustment process, so that the vehicle can achieve the target vehicle height while maintaining overall vehicle attitude stability.

[0005] The existing technology has the following shortcomings: The aforementioned existing technology mainly targets electronically controlled air suspension, and its actuators are relatively simple, failing to address the coordinated control issue between the two types of actuators when vehicles such as new energy vehicles simultaneously possess active suspension actuators and height adjustment mechanisms. When active suspension and height adjustment mechanisms such as air springs, hydropneumatic springs, or hydraulic cylinders are simultaneously installed on a vehicle, a lack of unified coordination can easily lead to a disconnect between height adjustment and attitude adjustment. For example, after height adjustment, the vehicle's roll or pitch may not have subsided, the active suspension may continuously output static support force to maintain vehicle attitude, and the height adjustment mechanism may not adjust the reference support state according to the offset state of the active suspension.

[0006] Existing technologies have not effectively distinguished between rapid attitude compensation and slow reference height adjustment, nor have they fully considered the problems caused by the long-term output of static support force by the active suspension, such as actuator center offset, increased energy consumption, increased pressure, and decreased control margin. They also lack a coordinated control mechanism to unload the active suspension through the height adjustment mechanism and restore the active suspension actuator to the center position.

[0007] In addition, existing technologies do not adequately consider factors such as uneven ground, wheel load constraints, and limitations on the stroke, pressure, and power of actuators. This may lead to misjudging changes in vehicle posture caused by slopes, twisted road surfaces, or single-wheel raised surfaces as abnormal vehicle posture, resulting in unnecessary forced leveling.

[0008] Therefore, for vehicles that simultaneously possess active suspension actuators and height adjustment mechanisms, it is necessary to address the coordinated control issues among vehicle height, roll attitude, pitch attitude, the neutral state of the active suspension actuator, road surface unevenness, and actuator constraints.

[0009] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0010] The purpose of this invention is to provide a method for jointly adjusting vehicle height and attitude with an active suspension actuator and a height adjustment mechanism, so as to solve the problems in the background art.

[0011] To achieve the above objectives, the present invention provides the following technical solution: a method for jointly adjusting the height and attitude of a vehicle, comprising an active suspension actuator and a height adjustment mechanism, including the following steps: The system collects data on the vehicle's four-wheel height, vehicle posture, suspension motion status, active suspension actuator status, height adjustment mechanism status, and vehicle motion status. The active suspension actuator serves as the fast execution channel, while the height adjustment mechanism serves as the slow execution channel. The collected information is used to determine the vehicle height status, vehicle attitude status, active suspension actuator center offset status, active suspension static support offset status, and ground status. Based on the determined states and the states of the height adjustment mechanism, select the working modes corresponding to the main adjustment of the height adjustment mechanism, the auxiliary attitude correction of the active suspension, the dominant height and attitude adjustment of the active suspension, the attitude maintenance on uneven ground, the unloading and neutral position recovery of the active suspension, or the fault protection / degradation. When the selected working mode is executed, the active suspension actuator shall be responsible for at least one of the following: rapid height adjustment, attitude correction, and oscillation suppression; the height adjustment mechanism shall be responsible for vehicle height and static support adjustment. When a continuous static support offset or actuator center position offset occurs, the target height, target pressure, or target displacement of the height adjustment mechanism shall be adjusted according to the direction and magnitude of the static support offset, the static support shall be transferred, and the active suspension actuator center position shall be controlled to recover. The system monitors the vehicle height error, attitude error, actuator center offset, and static support offset after adjustment. The current working mode ends when each parameter meets the corresponding threshold condition; otherwise, the working mode is reselected and the joint adjustment of vehicle height and attitude continues.

[0012] The active suspension actuator is responsible for rapid vehicle height adjustment, body roll correction, body pitch correction, or vertical oscillation suppression, while the height adjustment mechanism is responsible for target vehicle height adjustment and continuous static support adjustment.

[0013] The vehicle's four-wheel height is used to determine the average vehicle height, the difference between left and right heights, and the difference between front and rear heights. The vehicle height error is determined by comparing the target vehicle height with the average vehicle height. The corresponding attitude error is determined by comparing the target roll angle and the target pitch angle with the current vehicle roll angle and vehicle pitch angle, respectively.

[0014] The center offset state of the active suspension actuator is determined by the center offset between the actual position of the active suspension actuator and the preset center position and its duration.

[0015] When the center offset exceeds the corresponding center offset threshold and continues to reach the preset duration, it is determined that there is an actuator center offset at the corresponding wheel end, so as to distinguish the dynamic displacement caused by road input, vehicle body oscillation or short-term attitude compensation.

[0016] The static support offset state of the active suspension is determined by low-pass filtering or time averaging of the active suspension target support force, the actual support force of the active suspension, or the active suspension actuator pressure.

[0017] When the static support offset continuously deviates from zero or the preset reference value for a certain duration, and the static support offset direction is consistent with the current vehicle posture correction direction, it is determined that the active suspension actuator will continue to undertake the static support task generated by maintaining vehicle height or vehicle posture.

[0018] Ground condition is determined by at least one of the following: four-wheel height difference, four-wheel suspension travel difference, vehicle attitude angle, wheel load estimate, and change in active suspension support force.

[0019] When the ground unevenness parameter exceeds the corresponding threshold, or when the attitude correction causes the wheel load, active suspension actuator pressure, or active suspension actuator stroke to reach the corresponding limit, the uneven ground or twisted ground state is determined, and the leveling effect of the absolute roll angle and absolute pitch angle is limited.

[0020] Active suspension unloading and center position recovery correspond to continuous static support offset or actuator center position offset, and the height adjustment mechanism takes over the corresponding static support task.

[0021] The height adjustment mechanism at the wheel end corresponding to the static support offset adjusts the target height, target pressure, or target displacement according to the offset direction and magnitude, transferring the continuous static support borne by the active suspension actuator to the height adjustment mechanism, while retaining the dynamic compensation of the height and attitude of the active suspension actuator, and controlling the active suspension actuator to recover to the preset center position area.

[0022] The target support force at each wheel end of the active suspension includes height control component, roll control component, pitch control component, mid-position recovery component, and oscillation suppression component.

[0023] Each control component is enabled, disabled, or restricted according to the selected working mode. The roll control component adopts the opposite direction at the left and right wheel ends, and the pitch control component adopts the opposite direction at the front and rear wheel ends. During the unloading and neutral recovery of the active suspension, the vehicle height and attitude dynamic compensation are retained, and the static support transfer is undertaken by the height adjustment mechanism.

[0024] The technical effects and advantages provided by the present invention in the above technical solution are as follows: This invention establishes a fast-slow coordinated control mechanism between the active suspension actuator and the height adjustment mechanism. This mechanism enables the active suspension actuator to handle rapid dynamic compensation during roll, pitch, vertical oscillations, and height changes, while the height adjustment mechanism handles target vehicle height adjustment, static support redistribution, and long-term baseline support. This leverages the different response characteristics of the two types of actuators, improving the responsiveness and coordination of the combined vehicle height and attitude adjustment. Furthermore, this solution is applicable to height adjustment mechanisms such as air springs, hydropneumatic springs, and hydraulic cylinders, as well as active suspension actuators such as hydraulic, electro-hydraulic, electromechanical, and linear motors, demonstrating excellent system adaptability.

[0025] This invention incorporates the average vehicle height, left-right height difference, front-rear height difference, roll attitude, and pitch attitude into a unified state estimation and control process during vehicle height adjustment. Based on the height error, roll error, and pitch error, the corresponding adjustment requirements are determined. The height adjustment mechanism and the active suspension actuator work together to complete the vehicle height adjustment, roll correction, and pitch correction. This avoids the problems of asynchronous lifting of the four wheels and asynchronous convergence of roll and pitch caused by using only vehicle height as the adjustment target, thus improving the coordination and smoothness of the vehicle attitude during height adjustment.

[0026] This invention identifies the static support offset that the active suspension bears for a long time by performing low-pass filtering or time averaging on the active suspension support force, and judges the continuous load condition of the active suspension by combining the offset state of the active suspension actuator relative to the preset center position. When the static support offset or center offset meets the corresponding conditions, the continuous static support is gradually transferred to the height adjustment mechanism by adjusting the target height, target pressure or target displacement of the height adjustment mechanism, so that the active suspension can be unloaded and restored to the preset center area or low load area, thereby reducing the energy consumption and pressure burden generated by the long-term static support of the active suspension, while retaining the dynamic control capability of the active suspension.

[0027] This invention determines the unevenness of the ground by one or more of the following: four-wheel height difference, four-wheel suspension travel difference, vehicle attitude angle, wheel load estimate, and change in active suspension support force. It then combines wheel load, active suspension pressure, and actuator travel to determine whether the current attitude is suitable for continuing leveling. Under uneven or tortuous ground conditions, the absolute level of the vehicle body is not used as the sole control target. Instead, wheel load and actuator working range constraints are applied to the attitude correction process. This distinguishes between abnormal vehicle attitude and attitude changes caused by uneven ground, avoiding forced leveling that could lead to wheel overload, unloading, or actuator pressure or travel reaching the limit conditions. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0029] Figure 1 This is a flowchart of a method for jointly adjusting the height and attitude of a vehicle, which includes an active suspension actuator and a height adjustment mechanism, according to the present invention. Detailed Implementation

[0030] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that the description of this disclosure will be more complete and fully convey the concept of the exemplary embodiments to those skilled in the art.

[0031] This invention provides, for example Figure 1 The method for jointly adjusting the height and attitude of a vehicle, which includes an active suspension actuator and a height adjustment mechanism, includes the following steps: The system collects data on the vehicle's four-wheel height, vehicle posture, suspension motion status, active suspension actuator status, height adjustment mechanism status, and vehicle motion status. The active suspension actuator serves as the fast execution channel, while the height adjustment mechanism serves as the slow execution channel. The collected information is used to determine the vehicle height status, vehicle attitude status, active suspension actuator center offset status, active suspension static support offset status, and ground status. Based on the determined states and the states of the height adjustment mechanism, select the working modes corresponding to the main adjustment of the height adjustment mechanism, the auxiliary attitude correction of the active suspension, the dominant height and attitude adjustment of the active suspension, the attitude maintenance on uneven ground, the unloading and neutral position recovery of the active suspension, or the fault protection / degradation. When the selected working mode is executed, the active suspension actuator shall be responsible for at least one of the following: rapid height adjustment, attitude correction, and oscillation suppression; the height adjustment mechanism shall be responsible for vehicle height and static support adjustment. When a continuous static support offset or actuator center position offset occurs, the target height, target pressure, or target displacement of the height adjustment mechanism shall be adjusted according to the direction and magnitude of the static support offset, the static support shall be transferred, and the active suspension actuator center position shall be controlled to recover. The system monitors the vehicle height error, attitude error, actuator center offset, and static support offset after adjustment. The current working mode ends when each parameter meets the corresponding threshold condition; otherwise, the working mode is reselected and the joint adjustment of vehicle height and attitude continues.

[0032] This embodiment provides a method for jointly adjusting vehicle height and attitude, incorporating both an active suspension actuator and a height adjustment mechanism. It is applicable to suspension control scenarios where the vehicle is equipped with both an active suspension actuator and a height adjustment mechanism. The active suspension actuator can be a hydraulic, electro-hydraulic, electromechanical, or linear motor-type active suspension actuator; the height adjustment mechanism can be an air spring, a hydropneumatic spring, a hydraulic cylinder, an adjustable spring seat, or other mechanisms capable of changing the vehicle's height and static support state.

[0033] The active suspension actuator, acting as a fast-acting channel, is used for rapid vehicle height adjustment, body roll correction, body pitch correction, vertical oscillation suppression, and dynamic compensation during height adjustment. The height adjustment mechanism, acting as a slow-acting channel, is used for target vehicle height adjustment, static support adjustment, long-term baseline compensation, and active suspension unloading.

[0034] Among them, the rapid execution channel refers to the execution path that utilizes the dynamic response capability of the active suspension actuator to perform rapid height adjustment, roll correction, pitch correction, or oscillation suppression by actively changing the wheel end support force when the vehicle height or body posture changes.

[0035] The slow-speed execution path refers to the execution path that uses the height adjustment mechanism to change the vehicle's reference height or the static support state at the wheel ends, and undertakes the task of continuously maintaining the vehicle's height and static support. The fast-speed execution path coordinates with the slow-speed execution path according to the control tasks they undertake. The active suspension execution mechanism mainly undertakes dynamic adjustment, while the height adjustment mechanism mainly undertakes reference height adjustment and continuous static support adjustment.

[0036] When the active suspension actuator experiences static support offset or actuator center position deviation due to continuous static support, the continuous static support is transferred to the height adjustment mechanism by adjusting the target height, target pressure, or target displacement of the height adjustment mechanism, and the active suspension actuator is controlled to perform center position restoration, thereby preserving the execution stroke of the active suspension actuator for subsequent rapid height adjustment and dynamic attitude adjustment.

[0037] After the vehicle enters the height and attitude joint adjustment control, it continuously collects the vehicle's four-wheel height, body attitude, suspension motion state, active suspension actuator state, height adjustment mechanism state, and vehicle motion state according to the preset control cycle. This provides input for subsequent determination of the body height state, body attitude state, active suspension actuator center offset state, active suspension static support offset state, and ground state.

[0038] The four-wheel height of a vehicle refers to the vehicle height information corresponding to the left front wheel end, right front wheel end, left rear wheel end, and right rear wheel end, and is denoted as the left front wheel end height. Right front wheel height left rear wheel height and the height of the right rear wheel end The vehicle's four-wheel height is used to determine the average vehicle height, the difference between left and right heights, and the difference between front and rear heights, and serves as input information for judging the vehicle's height status and ground condition.

[0039] The height of the four wheels of a vehicle can be obtained through height sensors, displacement sensors, or detection devices that can acquire wheel end height information, which are located at the corresponding suspension positions.

[0040] Vehicle posture refers to the spatial attitude state of the vehicle body during vehicle operation, including at least the vehicle roll angle. and vehicle pitch angle It can also include roll rate, pitch rate, and state information related to the vertical motion of the vehicle body. Among them, the roll rate describes the tilt state of the vehicle body in the left-right direction, and the pitch rate describes the tilt state of the vehicle body in the front-back direction; the roll rate and pitch rate can be used to determine the attitude change process and for active suspension dynamic compensation.

[0041] Suspension motion state refers to the position and motion information of the suspension at each wheel end of the vehicle when it moves between the vehicle body and the wheel, including at least one or more of the following: four-wheel suspension travel, suspension relative speed, or wheel end displacement.

[0042] The four-wheel suspension travel is used to determine the current working position and remaining travel of the suspension at each wheel end; the relative speed of the suspension is used to determine the motion state between the vehicle body and the wheels; and the wheel end displacement is used to assist in determining the current suspension position at each wheel end. The suspension motion state is also used to determine the ground condition and the travel constraint of the active suspension actuator.

[0043] The status of the active suspension actuator refers to information that reflects the current working position, load, and support output of the active suspension actuator, including at least one or more of the following: active suspension actuator displacement, active suspension actuator pressure, active suspension target support force, and active suspension actual support force.

[0044] The displacement of the active suspension actuator is used to determine the current working position and center offset state of the active suspension actuator; the pressure of the active suspension actuator is used to determine the current load state of the active suspension actuator; the target support force of the active suspension refers to the wheel end support force that the active suspension actuator plans to output corresponding to the current control target; the actual support force of the active suspension refers to the wheel end support force that the active suspension actuator currently actually bears.

[0045] The target support force of the active suspension, the actual support force of the active suspension, or the pressure of the active suspension actuator are also used to determine whether the active suspension actuator continuously bears static support.

[0046] The status of the height adjustment mechanism refers to information reflecting its current position, pressure, control target, and execution status. When the height adjustment mechanism is an air spring, it can include the air spring pressure, target height, and corresponding valve status; when the height adjustment mechanism is a hydraulic spring, it can include the hydraulic spring pressure, displacement, and corresponding control status.

[0047] When the height adjustment mechanism is a hydraulic cylinder, it can include hydraulic cylinder pressure, hydraulic cylinder position, and target displacement; when the height adjustment mechanism is an adjustable spring seat or other mechanism that can change the vehicle height and static support state, it can include corresponding position, pressure, displacement, or working status information.

[0048] Vehicle motion status refers to the dynamic status information corresponding to the current driving and operation of the vehicle, which may include one or more of the following: vehicle speed, steering wheel angle, lateral acceleration, longitudinal acceleration, braking signal, driving mode, and height adjustment request.

[0049] Vehicle motion status is used to identify the current operating conditions of the vehicle and to help distinguish between attitude changes caused by dynamic driving, height adjustment needs, and vehicle states that require rapid compensation from active suspension.

[0050] After completing the collection of vehicle operation information, the collected information is used to determine the vehicle height status, vehicle attitude status, active suspension actuator center offset status, active suspension static support offset status, and ground status.

[0051] Vehicle height status refers to the vertical position of a vehicle determined by the height of its four wheels, average vehicle height, left-right height difference, front-rear height difference, and vehicle height error. It is used to determine the relationship between the current vehicle height and the target vehicle height, and whether vehicle height adjustment is needed.

[0052] Utilizing the height of the left front wheel end Right front wheel height left rear wheel height and the height of the right rear wheel end Determine the average height of the vehicle body : in, The average height of the vehicle body. This refers to the height of the left front wheel end. This refers to the height of the right front wheel end. This refers to the height of the left rear wheel end. This refers to the height of the right rear wheel end.

[0053] The left and right height differences of the vehicle are further determined using the height of the four wheels. : in, This is the difference in height between the two wheel ends on the left side of the vehicle and the two wheel ends on the right side of the vehicle, used to determine the vehicle's height status in the left and right directions.

[0054] Determine the front-to-rear height difference of a vehicle using the height of its four wheels. : in, This is the height difference between the two wheel ends of the front axle and the two wheel ends of the rear axle of a vehicle, used to determine the vehicle's height status in the longitudinal direction.

[0055] Obtain the target vehicle height corresponding to the current vehicle operating conditions. And utilize the target vehicle height with average vehicle height Determine vehicle height error : in, For vehicle height error, For the target vehicle height, This represents the current average height of the vehicle body.

[0056] Vehicle attitude state refers to the vehicle's attitude determined by its roll and pitch states, used to determine whether there are any attitude deviations requiring roll or pitch correction. Vehicle attitude state includes at least roll attitude error and pitch attitude error.

[0057] Utilizing the target roll angle and current vehicle body roll angle Determine the roll attitude error : in, For the roll attitude error, For the target roll angle, This represents the current vehicle body roll angle.

[0058] Using the target pitch angle and current vehicle pitch angle Determine pitch attitude error : in, For pitch attitude error, For the target pitch angle, This is the current vehicle pitch angle.

[0059] By average vehicle height Vehicle height error Left and right height difference and front and rear height difference Determine the vehicle body height status by measuring the roll attitude error. pitch attitude error Determine the vehicle's attitude status.

[0060] The active suspension actuator center offset state refers to the state in which the actual working position of the active suspension actuator deviates from the preset center position. It is used to determine whether the active suspension actuator has been working in a region deviating from the preset center position for a long time due to continuously undertaking the support task.

[0061] The preset center position is the reference working position pre-set by the active suspension actuator, which is used to reserve bidirectional dynamic adjustment stroke for the active suspension actuator.

[0062] For any wheel end Mid-offset of active suspension actuator for: in, Corresponding to the left front wheel end, right front wheel end, left rear wheel end, or right rear wheel end. For the first Mid-position offset of the active suspension actuator at each wheel end For the first The actual position of the active suspension actuator at each wheel end. For the first The active suspension actuator at each wheel is preset to the center position.

[0063] Continuous monitoring and the duration exceeding the preset median offset threshold. When If the center offset exceeds the preset threshold and continues for a preset duration, it is determined that there is a center offset of the active suspension actuator at the corresponding wheel end.

[0064] By combining the offset and duration, it is possible to distinguish between the dynamic displacement of the active suspension actuator caused by road input, vehicle body vibration, or short-term attitude compensation and the persistent mid-position offset.

[0065] The active suspension static support offset state refers to the state in which the active suspension actuator continuously provides static support for maintaining vehicle height or attitude, in addition to dynamic adjustment.

[0066] When the active suspension actuator continuously bears this part of the static support, its actuator pressure, support force or working position will continuously deviate from the corresponding reference state. Therefore, the active suspension static support offset state can be determined by the active suspension target support force, the active suspension actual support force or the active suspension actuator pressure.

[0067] Active suspension actuators provide both dynamic and continuous support during vehicle operation. Dynamic support primarily addresses road surface excitation, vertical vehicle body oscillation, roll dynamic correction, and pitch dynamic correction; continuous support corresponds to the support tasks continuously undertaken by the active suspension actuators to maintain vehicle height or attitude.

[0068] The target support force, actual support force, or actuator pressure of the active suspension are subjected to low-pass filtering or time averaging to weaken the rapidly changing dynamic support components, and the static support offset is determined using the processed continuous support state. .

[0069] Static support bias It refers to the first The continuous support offset obtained by the active suspension actuator at each wheel end after low-pass filtering or time averaging is used to determine whether the corresponding wheel end continuously bears static support, the direction of the static support offset, and the magnitude of the static support offset.

[0070] Monitor each wheel end separately The state of deviation from zero or a preset reference value, and the duration of the offset. When When the deviation from zero or the preset reference value continues and the duration reaches the duration threshold corresponding to the static support offset, the correspondence between the static support offset direction and the current vehicle body attitude correction direction is further determined.

[0071] For roll attitude correction, the static support offset is determined by the active suspension support direction at the left and right wheel ends to determine whether it corresponds to the current roll attitude correction direction; for pitch attitude correction, the static support offset is determined by the active suspension support direction at the front and rear wheel ends to determine whether it corresponds to the current pitch attitude correction direction.

[0072] When the static support bias persists and the bias direction is consistent with the current attitude correction direction, it is determined that the active suspension actuator continues to undertake the static support task generated by maintaining vehicle height or vehicle attitude.

[0073] Ground condition refers to the flatness of the ground corresponding to the current support position of the vehicle's four wheels and the impact of the ground condition on the vehicle's height and attitude adjustment. It is used to distinguish between vehicle attitude deviations that need to be actively corrected and changes in vehicle attitude caused by slopes, twisted ground, single wheel bumps or other uneven ground.

[0074] Ground unevenness parameters The calculation is performed using one or more of the following: four-wheel height difference, four-wheel suspension travel difference, vehicle attitude angle, wheel load estimate, and change in active suspension support force. It is used to evaluate the unevenness of the ground corresponding to the current support positions of the four wheels of the vehicle, and serves as a judgment parameter for the uneven ground attitude maintenance mode.

[0075] The four-wheel height difference reflects the difference in vehicle height caused by the support position of each wheel; the four-wheel suspension travel difference reflects the difference in travel of each wheel-end suspension due to different ground positions; the vehicle attitude angle reflects the current roll and pitch state of the vehicle; the wheel load estimate refers to the vertical load information of each wheel obtained based on the current wheel-end force state of the vehicle, used to determine the load borne by each wheel and the load distribution between the left and right wheels, front and rear wheels, or diagonal wheels; the change in active suspension support force reflects the change in wheel-end support generated by the active suspension actuator to maintain the current vehicle state.

[0076] when When the ground unevenness threshold is exceeded, the current vehicle is determined to meet the uneven ground judgment condition. Except... In addition, it also determines whether continuing to perform absolute attitude correction will cause wheel load, active suspension actuator pressure, or active suspension actuator stroke to reach the corresponding limit conditions.

[0077] When forced correction of roll or pitch attitude causes wheel load difference, diagonal wheel load state, actuator pressure, or actuator stroke to reach the corresponding limit conditions, the current ground state is determined to be uneven ground or twisted ground state.

[0078] After determining the vehicle height status, vehicle attitude status, active suspension actuator center offset status, active suspension static support offset status, and ground status, the system further reads the current pressure, displacement, target height, valve status, or hydraulic cylinder position of the height adjustment mechanism. Based on these statuses, the system selects the corresponding operating mode for the height adjustment mechanism's main adjustment, active suspension auxiliary attitude correction, active suspension dominant height and attitude adjustment, uneven ground attitude maintenance, active suspension unloading and center position recovery, or fault protection / degradation.

[0079] The working mode refers to the vehicle suspension control state determined by allocating the control tasks undertaken by the active suspension actuator and the height adjustment mechanism according to the current vehicle height state, vehicle attitude state, active suspension actuator center offset state, active suspension static support offset state, ground state, and height adjustment mechanism state.

[0080] The main adjustment of the height adjustment mechanism refers to the working mode in which the height adjustment mechanism undertakes the adjustment of vehicle height changes and continuous static support, while the active suspension actuator does not undertake the main static lifting and lowering tasks, but provides necessary dynamic compensation according to the dynamic state of the vehicle body.

[0081] When there is a height error between the average vehicle height and the target vehicle height that needs to be eliminated by the height adjustment mechanism, and the current pressure, displacement, and stroke of the height adjustment mechanism allow for height adjustment, the height adjustment mechanism is selected as the primary adjuster. In this operating mode, the height adjustment mechanism handles vehicle height adjustment and static support adjustment, while the active suspension actuator retains its dynamic compensation capability.

[0082] Active suspension assisted attitude correction refers to a working mode in which the active suspension actuator quickly adjusts the support force in response to changes in body roll or pitch, while the height adjustment mechanism undertakes the tasks of maintaining the vehicle's reference height and static support.

[0083] When the vehicle body roll attitude error, pitch attitude error, left-right height difference, or front-rear height difference reaches the corresponding attitude correction conditions, and the active suspension actuator needs to quickly correct the attitude changes generated during height adjustment, active suspension auxiliary attitude correction is selected. In this working mode, the height adjustment mechanism continues to undertake the tasks of vehicle body reference height and static support, while the active suspension actuator undertakes roll and pitch correction.

[0084] Active suspension dominant height and attitude adjustment refers to the working mode in which, when the vehicle needs to quickly adjust its height and correct its attitude in the current vehicle state, the active suspension actuator undertakes the rapid height adjustment, roll correction, pitch correction and oscillation suppression, while the height adjustment mechanism undertakes the subsequent static support adjustment according to the working state of the active suspension actuator.

[0085] When the response of the height adjustment mechanism cannot meet the current height adjustment needs, the height adjustment mechanism is limited by pressure, displacement or travel conditions, or the current vehicle state requires rapid and continuous height and attitude adjustment, the active suspension is selected to dominate the height and attitude adjustment.

[0086] In this operating mode, the active suspension actuator is responsible for rapid vehicle height adjustment, roll correction, pitch correction, and oscillation suppression, while the height adjustment mechanism is responsible for subsequent static support adjustment according to the travel, pressure, and static support offset state of the active suspension actuator.

[0087] Uneven ground attitude maintenance refers to a working mode in which, when the vehicle is on uneven or twisted ground, the sole control objective is not to eliminate all body roll and pitch angles, but rather to adjust the attitude correction output based on wheel load, active suspension actuator pressure, and active suspension actuator travel limit.

[0088] When the ground condition is uneven or twisted, or if continuing to perform absolute attitude correction would cause the wheel load, active suspension actuator pressure, or active suspension actuator stroke to reach the corresponding limits, the uneven ground attitude maintenance mode is selected. In this operating mode, the wheel load condition, active suspension actuator pressure, and active suspension actuator stroke are used as constraints for attitude adjustment.

[0089] Active suspension unloading and center position recovery refers to the working mode in which, when the active suspension actuator continuously bears static support or the active suspension actuator continuously deviates from the preset center position, the height adjustment mechanism takes over the corresponding static support task and controls the active suspension actuator to recover to the preset center position area.

[0090] Among them, active suspension unloading refers to reducing the static support task continuously borne by the active suspension actuator; center position recovery refers to reducing the center position offset between the actual position of the active suspension actuator and the preset center position.

[0091] When the center offset of the active suspension actuator exceeds the corresponding threshold and remains so for a preset time, or when the static support offset of the active suspension exceeds the corresponding threshold and remains so for a preset time, the active suspension unloading and center position restoration are selected. In this working mode, the static support is adjusted by the height adjustment mechanism, and the active suspension actuator performs center position restoration and dynamic attitude compensation.

[0092] Fault protection / degradation refers to a working mode that prohibits or restricts the height adjustment, attitude correction, oscillation suppression, or mid-position recovery functions affected by an abnormality when the active suspension actuator, height adjustment mechanism, corresponding energy supply component, or key sensor malfunctions, in order to prevent the corresponding control tasks from continuing to be executed under abnormal conditions.

[0093] When the active suspension actuator pressure, active suspension actuator stroke, motor power, pump flow, height adjustment mechanism pressure, or key sensor signal becomes abnormal, fault protection / degradation is selected to prohibit or restrict the abnormal adjustment function, while retaining the vehicle suspension functions that can be executed normally.

[0094] When there are no conditions requiring height adjustment, attitude correction, static support transfer, center position recovery, or fault protection, the vehicle remains in standby monitoring mode and continuously performs vehicle information collection and vehicle status assessment. When the entry conditions for any operating mode are met, the corresponding operating mode is entered.

[0095] After selecting the working mode, the selected working mode is executed. The active suspension actuator is responsible for at least one of the following: rapid height adjustment, attitude correction, and oscillation suppression. The height adjustment mechanism is responsible for adjusting the vehicle height and static support. When a continuous static support offset or actuator center position offset occurs, the target height, target pressure, or target displacement of the height adjustment mechanism is adjusted according to the direction and magnitude of the static support offset. The static support is transferred and the active suspension actuator is controlled to restore its center position.

[0096] Rapid height adjustment refers to the active suspension actuator dynamically adjusting the height difference between the current vehicle height and the target vehicle height by changing the support force at the four wheel ends. Rapid height adjustment is mainly used when the response of the height adjustment mechanism cannot meet the current height change requirements or when the vehicle needs to perform rapid and continuous height changes.

[0097] Attitude correction refers to the adjustment of body roll and pitch errors by the active suspension actuators by adjusting the support forces at different wheel ends. Specifically, roll correction generates a roll correction torque through the opposing support forces at the left and right wheel ends, while pitch correction generates a pitch correction torque through the opposing support forces at the front and rear wheel ends.

[0098] Oscillation suppression refers to the active suspension actuator outputting dynamic support force according to the vertical movement of the vehicle body or the movement state of the suspension, suppressing the vertical movement of the vehicle body or the relative movement of the suspension generated during vehicle height adjustment, road input, or attitude changes.

[0099] Vehicle height adjustment refers to the process by which a height adjustment mechanism adjusts the vehicle's baseline height by changing the target height, target pressure, target displacement, or corresponding execution state. Static support adjustment refers to the height adjustment mechanism undertaking the task of maintaining vertical support for the vehicle over a long period by changing the continuous support state at each wheel end.

[0100] In the main adjustment mode of the height adjustment mechanism, the height adjustment mechanism changes the height of the corresponding wheel end or the static support state according to the height error between the target vehicle height and the current vehicle height.

[0101] When the height adjustment mechanism is an air spring, the vehicle height is adjusted by inflating or deflating the corresponding air spring; when the height adjustment mechanism is a hydropneumatic spring, the vehicle height and static support are changed by the corresponding hydropneumatic adjustment process; when the height adjustment mechanism is a hydraulic cylinder, the vehicle height is adjusted by changing the position of the hydraulic cylinder; when other height adjustment mechanisms are used, the vehicle height or static support state is changed by the corresponding execution method.

[0102] During the main height adjustment process, the active suspension actuator does not undertake the continuous main lifting task, but provides dynamic compensation based on the vertical, lateral, or pitch movements of the vehicle body to suppress vehicle body oscillations and attitude changes generated during height adjustment.

[0103] In the active suspension assisted attitude correction mode, the height adjustment mechanism maintains the vehicle's reference height and static support, while the active suspension actuator changes the support force of the four wheels according to the roll attitude error and pitch attitude error.

[0104] During roll correction, the left and right wheels generate opposing support forces; during pitch correction, the front and rear wheels generate opposing support forces. The active suspension actuator achieves dynamic roll and pitch correction by rapidly changing the support forces of all four wheels.

[0105] In the active suspension dominant height and attitude adjustment mode, the active suspension actuator generates four-wheel height control components according to the height error, and generates roll control components and pitch control components according to the roll attitude error and pitch attitude error, thereby simultaneously performing rapid vehicle height adjustment, roll attitude correction and pitch attitude correction.

[0106] The height adjustment mechanism continuously monitors the stroke, pressure, and static support offset of the active suspension actuator. When the active suspension actuator continuously bears static support, the height adjustment mechanism participates in the static support adjustment.

[0107] In the uneven ground attitude maintenance mode, the leveling effect of limiting the absolute roll angle and absolute pitch angle of the vehicle body is limited, and priority is given to the difference in left and right wheel loads, the diagonal wheel load state, the pressure of the active suspension actuator, and the travel of the active suspension actuator.

[0108] When continuing to output active suspension support force in the current attitude correction direction will cause the corresponding wheel end load, actuator pressure, or actuator stroke to reach the limit condition, the attitude correction in the corresponding direction will be restricted to avoid continuous absolute leveling due to ground elevation differences, ground distortion, or changes in the position of a single wheel support.

[0109] Continuous static support offset refers to a state in which the static support offset of the active suspension continuously deviates from zero or a preset reference value, and this offset continues for a preset time. This state indicates that there is a continuous support component in the support task undertaken by the active suspension actuator.

[0110] Actuator center offset refers to the state where the actual position of the active suspension actuator deviates from the preset center position, and the offset exceeds the corresponding threshold and persists for a preset time. Actuator center offset is used to trigger active suspension unloading and center position restoration.

[0111] The static support offset direction refers to the direction of action corresponding to the continuous support action of the active suspension actuator, used to determine the direction in which the height adjustment mechanism needs to change the static support; the static support offset magnitude refers to the amount of static support offset. The degree of deviation from zero or a preset reference value is used to determine the current state of the active suspension actuator continuously bearing static support.

[0112] Target height refers to the vehicle height control target that the height adjustment mechanism needs to achieve after performing height adjustment; target pressure refers to the pressure control target when using air springs, hydropneumatic springs, hydraulic actuators, or other pressure-type height adjustment mechanisms; target displacement refers to the execution position control target when using hydraulic cylinders, adjustable spring seats, or other displacement-type height adjustment mechanisms.

[0113] Static support transfer refers to changing the static support borne by the height adjustment mechanism at the corresponding wheel end by adjusting the target height, target pressure, or target displacement of the height adjustment mechanism, thereby reducing the static support task continuously borne by the active suspension actuator. Static support transfer does not stop the operation of the active suspension actuator; the active suspension actuator continues to perform dynamic height and attitude compensation during the transfer process.

[0114] In the active suspension unloading and center position recovery mode, first identify the wheel end with a continuous static support offset or actuator center position offset, and then determine the static support offset direction, static support offset magnitude and actuator center position offset state of the corresponding wheel end.

[0115] For wheel ends with static support offset, adjust the target height, target pressure, or target displacement of the corresponding height adjustment mechanism according to the direction and magnitude of the static support offset. When the height adjustment mechanism is an air spring, adjust the target height or target pressure of the corresponding air spring; when the height adjustment mechanism is a hydraulic spring, adjust the target height, target pressure, or working state of the corresponding hydraulic spring; when the height adjustment mechanism is a hydraulic cylinder, adjust the target displacement or target pressure of the corresponding hydraulic cylinder.

[0116] By changing the static support state of the corresponding wheel end through the height adjustment mechanism, the static support that was originally continuously borne by the active suspension actuator is transferred to the height adjustment mechanism.

[0117] During the static support transfer process, the active suspension actuator continues to perform dynamic compensation for height and attitude, and continuously monitors the actual position of the active suspension actuator, actuator pressure, actual support force of the active suspension, center offset, and static support offset.

[0118] As the height adjustment mechanism assumes the corresponding static support, the active suspension actuator reduces the static support task used to continuously maintain the vehicle's height or attitude, and adjusts the active suspension actuator to the preset center position area through center position recovery control.

[0119] Active suspension actuator center position restoration refers to adjusting the center position offset of the active suspension actuator during the process of the height adjustment mechanism providing corresponding continuous static support, reducing the offset between the actual position of the active suspension actuator and the preset center position, and restoring the working stroke of the active suspension actuator for subsequent bidirectional dynamic adjustment.

[0120] The target support force at each wheel end of the active suspension consists of height control component, roll control component, pitch control component, mid-position recovery component, and oscillation suppression component. in, For the first The active suspension target support force at each wheel end; For the first Height control component at each wheel end; For the first Roll control component at each wheel end; For the first Pitch control components at each wheel end; For the first Active suspension unloading and mid-position recovery components at each wheel end; For the first Oscillation suppression component at each wheel end; Corresponding to the left front wheel end, right front wheel end, left rear wheel end, or right rear wheel end.

[0121] When height control uses PI control, the total support force component corresponding to the overall vehicle height adjustment is: in, This refers to the total supporting force component corresponding to the overall vehicle height adjustment. This is the height scaling factor; For high integral coefficients; This refers to the vehicle body height error; The time variable is used in the control process; the integral term corresponds to the accumulation of vehicle height error over time.

[0122] The total support force component corresponding to the vehicle height adjustment can be distributed to the four wheel ends according to the front and rear axle load ratio, or it can be evenly distributed to all four wheels. When using even distribution to all four wheels: in, For the first The height control component at each wheel end.

[0123] When PI control is used for roll control, the target roll correction torque is: in, The target tilt correction moment; This is the roll control proportional coefficient; The integral coefficient for roll control; This refers to the roll attitude error.

[0124] The target roll correction moment is distributed across the front and rear axles, and the roll control components corresponding to each wheel end are as follows: in, , , and These are the roll control components at the four wheel ends; The distribution coefficient of the target roll correction moment on the front axle; The distribution coefficient of the target roll correction moment on the rear axle; This refers to the front axle track. This refers to the rear axle track. The left and right wheel ends employ opposite roll control components to generate corresponding roll correction torques.

[0125] When pitch control uses PI control, the target pitch correction torque is: in, Pitch correction moment for the target; This is the pitch control proportional coefficient; The integral coefficient for pitch control; This refers to pitch attitude error.

[0126] The target pitch correction torque is distributed according to the front and rear axles, and the pitch control components corresponding to each wheel end are: in, , , and These are the pitch control components at the four wheel ends; The distribution coefficient of the pitch correction moment on the front axle for the target; The distribution coefficient of the pitch correction moment on the rear axle for the target; This is the distance from the vehicle's center of gravity to the front axle. This is the distance from the vehicle's center of gravity to the rear axle. The two wheel ends of the front axle use pitch control components in the same direction, while the two wheel ends of the rear axle use pitch control components in the opposite direction to those of the front axle.

[0127] For wheel ends with actuator midpoint offset, the midpoint recovery control component is: in, For the first The median recovery component of each wheel end; For the first The median recovery ratio of each wheel end; For the first The median recovery integral coefficient of each wheel end; For the first The midpoint offset between the actual position and the preset midpoint position of the active suspension actuator at each wheel end; This is a time variable used to control the process.

[0128] The static support transfer of the center position recovery control and height adjustment mechanism simultaneously participates in the active suspension unloading and center position recovery process. The height adjustment mechanism assumes continuous static support by adjusting the target height, target pressure, or target displacement, while the active suspension center position recovery control is used to reduce actuator center position offset, and the active suspension retains dynamic compensation for height and attitude.

[0129] When velocity feedback is used for oscillation suppression, the corresponding relationship is as follows: in, For the first The oscillation suppression coefficient corresponding to each wheel end For the first The vertical velocity of the vehicle body or the speed of the suspension corresponds to each wheel end. This control relationship is used to suppress the vertical motion of the vehicle body or the relative motion of the suspension.

[0130] In different operating modes, the altitude control component, roll control component, pitch control component, mid-position recovery component, and oscillation suppression component are enabled, disabled, or limited accordingly.

[0131] In the main adjustment mode of the height adjustment mechanism, the height adjustment mechanism undertakes the main tasks of height adjustment and static support. The active suspension height control is turned off, the roll control and pitch control are turned off or limited, the mid-position recovery control is turned off, and the oscillation suppression control is turned off or limited. When attitude changes or vertical oscillations that require dynamic compensation occur during the height adjustment process, the active suspension actuator participates in the corresponding dynamic compensation.

[0132] In the active suspension assisted attitude correction mode, height control is off or limited, roll control and pitch control are enabled, center position recovery control is off, and oscillation suppression control is enabled or limited; the height adjustment mechanism continues to perform the tasks of reference height and static support.

[0133] In the active suspension's dominant height and attitude adjustment mode, height control, roll control, and pitch control are enabled, center position recovery control is disabled, and oscillation suppression control is enabled. The active suspension actuator simultaneously undertakes rapid height adjustment, roll attitude correction, pitch attitude correction, and vertical oscillation suppression. The height adjustment mechanism participates in subsequent slow compensation according to the active suspension's static support state.

[0134] In the uneven ground attitude maintenance mode, height control, roll control, and pitch control are turned off or limited, mid-position recovery control is turned off, oscillation suppression control is turned off or limited, and attitude correction output is limited by wheel load, active suspension actuator pressure, and active suspension actuator stroke.

[0135] In the active suspension unloading and center-position recovery mode, height control, roll control, and pitch control maintain their control functions for dynamic compensation of vehicle height and attitude. Center-position recovery control is activated, oscillation suppression control is activated, and the height adjustment mechanism also undertakes the task of static support transfer.

[0136] In fault protection / degradation mode, height control, roll control, pitch control, center position recovery control, and oscillation suppression control are turned off or limited based on abnormal conditions of the active suspension actuator, height adjustment mechanism, sensors, and corresponding vehicle status.

[0137] The PI control described above is one implementation method for calculating the target support force of an active suspension. Height control, roll control, pitch control, and mid-position recovery control can also employ PID control, state feedback control, model predictive control, quadratic programming control, lookup table control, or adaptive control.

[0138] When different control methods are adopted, the task allocation relationship between the active suspension actuator as the fast execution channel and the height adjustment mechanism as the slow execution channel remains consistent, and the working mode selection continues to be carried out using the vehicle height state, vehicle attitude state, active suspension actuator center offset state, active suspension static support offset state and ground state.

[0139] After completing the adjustment corresponding to the current working mode, monitor the adjusted vehicle height error, attitude error, actuator center offset, and static support offset. If each parameter meets the corresponding threshold condition, end the current working mode; otherwise, reselect the working mode and continue the joint adjustment of vehicle height and attitude.

[0140] The adjusted vehicle height error refers to the error between the current average vehicle height (after re-acquiring the four wheel heights of the vehicle) and the target vehicle height, which is used to determine whether the current vehicle height meets the corresponding control requirements.

[0141] The adjusted attitude error includes roll attitude error and pitch attitude error. It refers to the attitude deviation determined after re-acquiring the vehicle roll angle and vehicle pitch angle after executing the current working mode and comparing them with the target roll angle and target pitch angle respectively. It is used to judge whether the roll attitude and pitch attitude meet the corresponding control requirements.

[0142] The adjusted actuator center offset refers to the value redefined after executing the current operating mode, using the actual position of the active suspension actuator and the preset center position. It is used to determine whether the active suspension actuator is in the permissible mid-range operating area.

[0143] The adjusted static support offset refers to the offset re-determined after executing the current operating mode, using the active suspension target support force, the actual active suspension support force, or the active suspension actuator pressure. It is used to determine whether the active suspension actuator continues to bear the static support task that needs to be transferred to the height adjustment mechanism.

[0144] The corresponding threshold conditions refer to the control completion judgment conditions set for vehicle height error, roll attitude error, pitch attitude error, actuator center offset, and static support offset, respectively, which are used to determine whether the current height adjustment, attitude correction, and active suspension unloading and center position recovery are completed.

[0145] The system continuously collects data on the vehicle's four-wheel height, vehicle posture, suspension motion status, active suspension actuator status, and height adjustment mechanism status, and then redetermines the vehicle height status, vehicle posture status, active suspension actuator center offset status, active suspension static support offset status, and ground status.

[0146] The average vehicle height will be calculated again using the updated four-wheel height. And vehicle height error The updated body roll angle and body pitch angle are used to further determine the roll attitude error. pitch attitude error The midpoint offset is further determined using the updated actual position of the active suspension actuator. The updated target support force of the active suspension, the actual support force of the active suspension, or the actuator pressure are used to further determine the static support offset. .

[0147] When the vehicle height error Satisfying the corresponding height error threshold condition and roll attitude error Satisfying the corresponding roll error threshold condition and pitch attitude error Satisfying the corresponding pitch error threshold condition and the center offset of each wheel-end active suspension actuator The corresponding median offset threshold condition is met, and the static support offset of the active suspension at each wheel end is... When the corresponding static support offset threshold condition is met, it is determined that the current vehicle height and attitude joint adjustment has reached the current control target, the current working mode ends, and the vehicle enters standby monitoring state.

[0148] When any parameter does not meet the corresponding threshold condition, the joint adjustment of vehicle height and attitude is not terminated. Instead, the working mode is reselected using the updated vehicle height status, vehicle attitude status, active suspension actuator center offset status, active suspension static support offset status, ground status, and height adjustment mechanism status.

[0149] Reselecting the operating mode means that after the current operating mode is executed, the operating mode is re-determined based on the updated vehicle status, rather than maintaining the original operating mode. If the vehicle status still meets the control conditions of the current operating mode, the corresponding adjustment continues; if the vehicle status meets the entry conditions of another operating mode, the operating mode corresponding to the updated vehicle status is switched.

[0150] If there is still a vehicle height error that needs to be handled by the height adjustment mechanism, the main height adjustment of the height adjustment mechanism will continue to be executed; if there is a roll or pitch error that needs to be quickly handled by the active suspension, the active suspension will perform auxiliary attitude correction; if there is a need for rapid height and attitude adjustment, the active suspension will perform dominant height and attitude adjustment; if the ground condition meets the uneven ground judgment conditions, the uneven ground attitude will be maintained.

[0151] If the center offset of the active suspension actuator or the static support offset meets the corresponding entry conditions, the active suspension unloading and center position restoration are performed; if an abnormality is detected in the actuator, sensor or corresponding working state, fault protection / degradation is performed.

[0152] Throughout the process of joint vehicle height and attitude adjustment, the active suspension actuator undertakes rapid dynamic adjustment, while the height adjustment mechanism undertakes vehicle reference height and continuous static support adjustment. The active suspension actuator can compensate for vehicle roll, pitch, and vertical oscillations when the height adjustment mechanism performs slow height adjustments; the height adjustment mechanism can take over the corresponding static support task when the active suspension actuator continuously generates static support offset or actuator center offset.

[0153] By continuously collecting vehicle status data, determining vehicle status, selecting working modes, executing working modes, and monitoring adjustment results, the vehicle height, body posture, neutral state of active suspension actuators, and static support state are jointly adjusted.

[0154] In one embodiment, a computer-readable storage medium is provided, storing a computer program for implementing a method for jointly adjusting the height and attitude of a vehicle equipped with an active suspension actuator and a height adjustment mechanism. The computer-readable storage medium can be used to store program instructions that need to be executed during the joint adjustment of vehicle height and attitude, and can be read and executed by a processor.

[0155] After the computer program is executed by the processor, the processor acquires the vehicle's four-wheel height, vehicle posture, suspension motion state, active suspension actuator state, height adjustment mechanism state, and vehicle motion state. It then processes the acquired information according to the control relationship where the active suspension actuator is the fast execution channel and the height adjustment mechanism is the slow execution channel.

[0156] The processor uses the acquired information to determine the vehicle height status, vehicle attitude status, active suspension actuator center offset status, active suspension static support offset status, and ground status. Based on the above status and the height adjustment mechanism status, it determines the current corresponding working mode from the following: main adjustment of the height adjustment mechanism, active suspension auxiliary attitude correction, active suspension dominant height and attitude adjustment, uneven ground attitude maintenance, active suspension unloading and center position recovery, and fault protection / degradation.

[0157] After determining the working mode, the processor outputs control commands according to the corresponding control logic, controlling the active suspension actuator to perform at least one of the following: rapid height adjustment, attitude correction, and oscillation suppression, and controlling the height adjustment mechanism to perform vehicle height and static support adjustment.

[0158] When a persistent static support offset or actuator center position offset is detected, the target height, target pressure, or target displacement of the height adjustment mechanism is adjusted according to the direction and magnitude of the static support offset, and the persistent static support is transferred to the height adjustment mechanism. At the same time, the active suspension actuator is controlled to perform center position restoration.

[0159] Furthermore, the computer program is also used to control the processor to continuously monitor the adjusted vehicle height error, attitude error, actuator center offset, and static support offset.

[0160] When each parameter meets the corresponding threshold condition, the current working mode ends; when any parameter does not meet the corresponding threshold condition, the working mode is redefined using the updated vehicle status, and the joint adjustment of vehicle height and attitude continues.

[0161] The computer-readable storage medium can be a non-volatile storage medium or other program storage medium capable of storing computer programs and being read by a processor. After the computer program is loaded and executed by the processor in the vehicle controller, the coordinated control between the active suspension actuator and the height adjustment mechanism can be completed according to the above control process, realizing the joint adjustment of vehicle height, body posture, active suspension actuator neutral state and static support state.

[0162] This invention establishes a fast-slow coordinated control mechanism between the active suspension actuator and the height adjustment mechanism. This mechanism enables the active suspension actuator to handle rapid dynamic compensation during roll, pitch, vertical oscillations, and height changes, while the height adjustment mechanism handles target vehicle height adjustment, static support redistribution, and long-term baseline support. This leverages the different response characteristics of the two types of actuators, improving the responsiveness and coordination of the combined vehicle height and attitude adjustment. Furthermore, this solution is applicable to height adjustment mechanisms such as air springs, hydropneumatic springs, and hydraulic cylinders, as well as active suspension actuators such as hydraulic, electro-hydraulic, electromechanical, and linear motors, demonstrating excellent system adaptability.

[0163] This invention incorporates the average vehicle height, left-right height difference, front-rear height difference, roll attitude, and pitch attitude into a unified state estimation and control process during vehicle height adjustment. Based on the height error, roll error, and pitch error, the corresponding adjustment requirements are determined. The height adjustment mechanism and the active suspension actuator work together to complete the vehicle height adjustment, roll correction, and pitch correction. This avoids the problems of asynchronous lifting of the four wheels and asynchronous convergence of roll and pitch caused by using only vehicle height as the adjustment target, thus improving the coordination and smoothness of the vehicle attitude during height adjustment.

[0164] This invention identifies the static support offset that the active suspension bears for a long time by performing low-pass filtering or time averaging on the active suspension support force, and judges the continuous load condition of the active suspension by combining the offset state of the active suspension actuator relative to the preset center position. When the static support offset or center offset meets the corresponding conditions, the continuous static support is gradually transferred to the height adjustment mechanism by adjusting the target height, target pressure or target displacement of the height adjustment mechanism, so that the active suspension can be unloaded and restored to the preset center area or low load area, thereby reducing the energy consumption and pressure burden generated by the long-term static support of the active suspension, while retaining the dynamic control capability of the active suspension.

[0165] This invention determines the unevenness of the ground by one or more of the following: four-wheel height difference, four-wheel suspension travel difference, vehicle attitude angle, wheel load estimate, and change in active suspension support force. It then combines wheel load, active suspension pressure, and actuator travel to determine whether the current attitude is suitable for continuing leveling. Under uneven or tortuous ground conditions, the absolute level of the vehicle body is not used as the sole control target. Instead, wheel load and actuator working range constraints are applied to the attitude correction process. This distinguishes between abnormal vehicle attitude and attitude changes caused by uneven ground, avoiding forced leveling that could lead to wheel overload, unloading, or actuator pressure or travel reaching the limit conditions.

[0166] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A method for jointly adjusting vehicle height and attitude, comprising an active suspension actuator and a height adjustment mechanism, characterized in that, Includes the following steps: The system collects data on the vehicle's four-wheel height, vehicle posture, suspension motion status, active suspension actuator status, height adjustment mechanism status, and vehicle motion status. The active suspension actuator serves as the fast execution channel, while the height adjustment mechanism serves as the slow execution channel. The collected information is used to determine the vehicle height status, vehicle attitude status, active suspension actuator center offset status, active suspension static support offset status, and ground status. Based on the determined states and the states of the height adjustment mechanism, select the working modes corresponding to the main adjustment of the height adjustment mechanism, the auxiliary attitude correction of the active suspension, the dominant height and attitude adjustment of the active suspension, the attitude maintenance on uneven ground, the unloading and neutral position recovery of the active suspension, or the fault protection / degradation. When the selected working mode is executed, the active suspension actuator shall be responsible for at least one of the following: rapid height adjustment, attitude correction, and oscillation suppression; the height adjustment mechanism shall be responsible for vehicle height and static support adjustment. When a continuous static support offset or actuator center position offset occurs, the target height, target pressure, or target displacement of the height adjustment mechanism shall be adjusted according to the direction and magnitude of the static support offset, the static support shall be transferred, and the active suspension actuator center position shall be controlled to recover. The system monitors the vehicle height error, attitude error, actuator center offset, and static support offset after adjustment. The current working mode ends when each parameter meets the corresponding threshold condition; otherwise, the working mode is reselected and the joint adjustment of vehicle height and attitude continues.

2. The method for jointly adjusting vehicle height and attitude with an active suspension actuator and a height adjustment mechanism according to claim 1, characterized in that, The active suspension actuator is responsible for rapid vehicle height adjustment, body roll correction, body pitch correction, or vertical oscillation suppression, while the height adjustment mechanism is responsible for target vehicle height adjustment and continuous static support adjustment.

3. The method for jointly adjusting vehicle height and attitude with an active suspension actuator and a height adjustment mechanism according to claim 1, characterized in that, The vehicle's four-wheel height is used to determine the average vehicle height, the difference between left and right heights, and the difference between front and rear heights. The vehicle height error is determined by comparing the target vehicle height with the average vehicle height. The corresponding attitude error is determined by comparing the target roll angle and the target pitch angle with the current vehicle roll angle and vehicle pitch angle, respectively.

4. A method for jointly adjusting vehicle height and attitude with an active suspension actuator and a height adjustment mechanism according to claim 1, characterized in that, The center offset state of the active suspension actuator is determined by the center offset between the actual position of the active suspension actuator and the preset center position and its duration.

5. A method for jointly adjusting vehicle height and attitude with an active suspension actuator and a height adjustment mechanism according to claim 4, characterized in that, When the center offset exceeds the corresponding center offset threshold and continues to reach the preset duration, it is determined that there is an actuator center offset at the corresponding wheel end, so as to distinguish the dynamic displacement caused by road input, vehicle body oscillation or short-term attitude compensation.

6. A method for jointly adjusting vehicle height and attitude with an active suspension actuator and a height adjustment mechanism according to claim 1, characterized in that, The static support offset state of the active suspension is determined by low-pass filtering or time averaging of the active suspension target support force, the actual support force of the active suspension, or the active suspension actuator pressure.

7. A method for jointly adjusting vehicle height and attitude with an active suspension actuator and a height adjustment mechanism according to claim 6, characterized in that, When the static support offset continuously deviates from zero or the preset reference value for a certain duration, and the static support offset direction is consistent with the current vehicle posture correction direction, it is determined that the active suspension actuator will continue to undertake the static support task generated by maintaining vehicle height or vehicle posture.

8. A method for jointly adjusting vehicle height and attitude with an active suspension actuator and a height adjustment mechanism according to claim 1, characterized in that, Ground condition is determined by at least one of the following: four-wheel height difference, four-wheel suspension travel difference, vehicle attitude angle, wheel load estimate, and change in active suspension support force.

9. A method for jointly adjusting vehicle height and attitude with an active suspension actuator and a height adjustment mechanism according to claim 1, characterized in that, When the ground unevenness parameter exceeds the corresponding threshold, or when the attitude correction causes the wheel load, active suspension actuator pressure, or active suspension actuator stroke to reach the corresponding limit, the uneven ground or twisted ground state is determined, and the leveling effect of the absolute roll angle and absolute pitch angle is limited.

10. A method for jointly adjusting vehicle height and attitude with an active suspension actuator and a height adjustment mechanism according to claim 1, characterized in that, Active suspension unloading and center position recovery correspond to continuous static support offset or actuator center position offset, and the height adjustment mechanism takes over the corresponding static support task.

11. A method for jointly adjusting vehicle height and attitude with an active suspension actuator and a height adjustment mechanism according to claim 10, characterized in that, The height adjustment mechanism at the wheel end corresponding to the static support offset adjusts the target height, target pressure, or target displacement according to the offset direction and magnitude, transferring the continuous static support borne by the active suspension actuator to the height adjustment mechanism, while retaining the dynamic compensation of the height and attitude of the active suspension actuator, and controlling the active suspension actuator to recover to the preset center position area.

12. A method for jointly adjusting vehicle height and attitude with an active suspension actuator and a height adjustment mechanism according to claim 1, characterized in that, The target support force at each wheel end of the active suspension includes height control component, roll control component, pitch control component, mid-position recovery component, and oscillation suppression component.

13. A method for jointly adjusting vehicle height and attitude with an active suspension actuator and a height adjustment mechanism according to claim 12, characterized in that, Each control component is enabled, disabled, or restricted according to the selected working mode. The roll control component adopts the opposite direction at the left and right wheel ends, and the pitch control component adopts the opposite direction at the front and rear wheel ends. During the unloading and neutral recovery of the active suspension, the vehicle height and attitude dynamic compensation are retained, and the static support transfer is undertaken by the height adjustment mechanism.

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