Active suspension hydraulic control system and control method

Abstract

The invention relates to the technical field of vehicle chassis control, and discloses an active suspension hydraulic control system and control method.The active suspension hydraulic control system comprises a multi-dimensional sensing module, an intelligent control unit, a distributed hydraulic execution module and a grading fault-tolerant module; the multi-dimensional sensing module comprises a millimeter wave radar, an inertial measurement unit IMU arranged at the mass center of a vehicle body, a wheel six-component sensor integrated on a hub bearing and a laser positioning vehicle body attitude sensor. The millimeter-wave radar previews the three-dimensional contour of a front road surface 0-10 m ahead, previewing and real-time double sensing of road condition information are achieved in combination with real-time state data of the IMU and the vehicle body attitude sensor, the total delay from road condition recognition to control instruction generation is shortened in cooperation with parallel preprocessing of an FPGA in the intelligent control unit, and when a vehicle runs to a bumpy road surface, the real-time state data of the vehicle body attitude sensor are compared with the real-time state data of the IMU and the vehicle body attitude sensor. The improved MPC algorithm can adjust the suspension rigidity in advance based on preview data, the vertical acceleration fluctuation amplitude of a vehicle body is reduced, and the riding comfort of passengers is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of vehicle chassis control technology, specifically to an active suspension hydraulic control system and control method. Background Technology

[0002] The active suspension system is a core chassis component that improves ride quality and handling safety. It balances the ride comfort and stability of the vehicle under different road conditions by actively adjusting the stiffness and damping characteristics of the suspension.

[0003] While existing active suspension hydraulic control systems have achieved basic dynamic adjustment functions, they still have the following problems in terms of adaptability to complex working conditions, energy economy, and fault safety: Existing systems mostly rely on real-time feedback data such as vehicle acceleration and wheel displacement for control, lacking the ability to anticipate road conditions ahead. When a vehicle travels on a bumpy or uneven road surface, the traditional suspension system must wait for the wheels to contact the road before it can trigger an adjustment, resulting in a lag in vehicle posture adjustment and making it prone to bumps or rolls. At the same time, the perception dimension of a single type of sensor is limited, and it is impossible to fully acquire information such as the three-dimensional contour of the road surface and the distribution of wheel loads, thus limiting the accuracy of control decisions. Existing distributed hydraulic suspensions mostly use a single volumetric accumulator for energy recovery, which cannot achieve precise energy storage and release according to the actual pressure requirements of the hydraulic circuit. When the hydraulic circuit pressure is low, the accumulator cannot effectively absorb energy, and when the pressure is too high, energy overflow and waste are likely to occur, causing the hydraulic pump to operate under high load for a long time. Most systems use fixed-parameter PID control or simple model predictive control, without considering the performance requirements under different road conditions. When driving on a smooth road, excessive pursuit of smoothness will lead to increased energy consumption. When driving on a bumpy road, if the handling weight is insufficient, it is easy to cause oversteering or understeering of the vehicle. In addition, a single processor architecture is difficult to balance the rapid preprocessing of multi-sensor data and the real-time solution of complex algorithms. The delay in the generation of control commands further affects the suspension adjustment effect. Existing systems often focus on hardware redundancy, such as configuring backup hydraulic pumps or solenoid valves, but lack collaborative compensation at the software algorithm level. When a single road sensor fails, data distortion can easily occur, leading to inaccurate control. When a single hydraulic actuator fails, it can only shut down the faulty circuit and rely on mechanical spring support, unable to maintain active control functions. The accuracy of vehicle posture control drops significantly, seriously affecting driving safety. Summary of the Invention

[0004] This invention provides an active suspension hydraulic control system and control method to solve the problems mentioned in the background art.

[0005] This invention provides the following technical solution: an active suspension hydraulic control system, comprising a multi-dimensional perception module, an intelligent control unit, a distributed hydraulic execution module, and a hierarchical fault-tolerant module; The multi-dimensional perception module includes millimeter-wave radar, an inertial measurement unit (IMU) located at the center of gravity of the vehicle body, a wheel six-component force sensor integrated into the wheel hub bearing, and a laser positioning vehicle body attitude sensor. The intelligent control unit is a dual-core heterogeneous processor consisting of an FPGA and an ARM Cortex-A9. The FPGA is used for sensor data preprocessing, and the ARM is used to run the road condition recognition model and the improved MPC algorithm. The optimization objectives of the improved MPC algorithm are to minimize the vertical acceleration of the vehicle body, minimize the fluctuation of wheel ground force, and minimize hydraulic energy consumption. The distributed hydraulic actuator module includes independent hydraulic units corresponding to the four wheels and a central energy storage array with three pressure ranges. Each independent hydraulic unit consists of a micro variable piston pump, a two-stage electro-hydraulic proportional valve and a dual-chamber hydraulic cylinder. The hierarchical fault-tolerant module includes a hardware redundancy unit and a strategy library with preset three-level fault-tolerant modes; the multi-dimensional perception module is connected to the intelligent control unit and the hierarchical fault-tolerant module respectively via Ethernet / TSN bus, the intelligent control unit outputs control commands to the distributed hydraulic actuation module, and the hierarchical fault-tolerant module feeds back fault-tolerant commands to the intelligent control unit.

[0006] As a preferred embodiment of the present invention, the rodless chamber of the dual-chamber hydraulic cylinder has a diameter of 90mm, a rod chamber diameter of 60mm, and a stroke of 250mm. The rodless chamber and the rod chamber are supplied with oil independently, and the suspension stiffness is continuously adjustable through differential pressure control.

[0007] As a preferred embodiment of the present invention, the three accumulators of the central energy storage array correspond to pressure ranges of 5-15MPa, 15-25MPa, and 25-35MPa, with volumes of 5L, 8L, and 12L respectively. A pressure monitoring unit is configured to collect pressure data of each accumulator in real time to control the accumulator switching valve group to achieve automatic switching of pressure ranges.

[0008] As a preferred embodiment of the present invention, the two-stage electro-hydraulic proportional valve includes a primary flow coarse adjustment valve and a secondary flow fine adjustment valve, with a total response time ≤8ms, and is used to precisely control the oil inlet and outlet flow of the dual-chamber hydraulic cylinder.

[0009] As a preferred embodiment of the present invention, the miniature variable displacement piston pump has a displacement of 5-20 mL / r and a maximum output pressure of 35 MPa, and is used to provide adjustable hydraulic power for independent hydraulic units.

[0010] As a preferred technical solution of the present invention, the improved MPC algorithm presets 5-step prediction time domain and 3-step control time domain, and dynamically adjusts the optimization target weight according to the road condition type output by the road condition identification model: energy consumption optimization weight ≥ 0.4 under smooth road conditions, and smoothness optimization weight ≥ 0.6 under severely bumpy road conditions.

[0011] As a preferred technical solution of the present invention, the three-level fault-tolerant mode is specifically as follows: the first-level fault tolerance uses a federated Kalman filter data fusion algorithm to compensate for fault data; the second-level fault tolerance uses a pseudo-inverse torque distribution algorithm to distribute the control torque of the fault unit to the other three independent hydraulic units; and the third-level fault tolerance uses a ceiling damping semi-active control algorithm to adjust the suspension damping characteristics.

[0012] As a preferred embodiment of the present invention, the hardware redundancy unit is configured with a backup solenoid directional valve and a pressure sensor for each independent hydraulic unit. The backup solenoid directional valve is of the same model as the main solenoid directional valve and is used to switch the oil circuit in case of failure.

[0013] As a preferred embodiment of the present invention, the transmission cycle of the Ethernet / TSN bus is 10ms, which is used to realize synchronous data transmission between the multi-dimensional sensing module, the intelligent control unit, and the hierarchical fault-tolerant module.

[0014] A control method for an active suspension hydraulic control system includes the following steps: S1. Pre-aiming perception and status acquisition: The multi-dimensional perception module synchronously acquires data on the three-dimensional contour of the road surface, vehicle motion status, wheel load and body posture, and transmits the data through the Ethernet / TSN bus after signal conditioning. S2. Road condition identification and control decision: The FPGA performs Kalman filtering and time synchronization preprocessing on the data, the ARM Cortex-A9 calls the road condition identification model to determine the road condition type, and the improved MPC algorithm solves the optimal control quantity and generates control commands. S3. Distributed execution and energy consumption optimization: The distributed hydraulic execution module receives control commands, adjusts the hydraulic pump pressure and proportional valve opening, and the central energy storage array realizes pressure matching energy storage and release. S4. Graded fault tolerance and safety assurance: The graded fault tolerance module monitors the working status of components, activates the corresponding fault tolerance mode according to the fault type, sends fault tolerance instructions to the intelligent control unit, and triggers an alarm.

[0015] The present invention has the following beneficial effects: 1. This active suspension hydraulic control system and method integrates millimeter-wave radar, IMU, wheel six-component force sensors, and laser vehicle attitude sensors through a multi-dimensional perception module. The millimeter-wave radar pre-aims at the three-dimensional contour of the road surface ahead 0-10m in advance. Combined with the real-time status data of the IMU and vehicle attitude sensors, it achieves dual perception of road condition information in both pre-aiming and real-time. With the parallel preprocessing of the FPGA in the intelligent control unit, the total delay from road condition recognition to control command generation is shortened. When the vehicle travels on a bumpy road, the improved MPC algorithm can adjust the suspension stiffness in advance based on the pre-aiming data, reducing the vertical acceleration fluctuation of the vehicle body and greatly improving passenger comfort.

[0016] 2. The active suspension hydraulic control system and control method, through the three-pressure range central energy storage array of the distributed hydraulic actuator module, through the graded pressure design of 5-15MPa, 15-25MPa, and 25-35MPa, accurately matches the hydraulic energy demand under different working conditions. When the wheel rolls over the raised road surface, the hydraulic cylinder pressure increases, and the accumulator in the corresponding pressure range quickly stores energy. When the vehicle gets stuck in potholes or accelerates, the accumulator releases energy to assist in oil supply.

[0017] 3. The active suspension hydraulic control system and control method adopt an FPGA+ARM Cortex-A9 dual-core heterogeneous architecture through the intelligent control unit. The FPGA is responsible for parallel preprocessing such as filtering and synchronization of multi-sensor data, while the ARM focuses on road condition recognition and improved MPC algorithm operation, realizing efficient collaboration between data processing and decision generation. The improved MPC algorithm presets 5-step prediction time domain and 3-step control time domain, and dynamically adjusts and optimizes the weights based on the recognition results of 4 types of road conditions: energy consumption weight ≥ 0.4 under smooth road conditions to reduce energy consumption; ride comfort weight ≥ 0.6 under severely bumpy road conditions to ensure a good riding experience.

[0018] 4. The active suspension hydraulic control system and control method construct a full-link fault-tolerant system of "hardware redundancy + software algorithm" through a hierarchical fault-tolerant module. The first level of fault tolerance fuses multi-sensor data through federated Kalman filtering, ensuring data accuracy even if a single sensor fails. The second level of fault tolerance adopts pseudo-inverse torque distribution, distributing the control torque of the failed hydraulic unit to the other three units, keeping the body roll and pitch angles within ±3°, far exceeding the mechanical support accuracy of existing technologies. The third level of fault tolerance switches to semi-active control of the roof damping, maintaining basic suspension adjustment function even when two units fail, improving driving safety under system failure conditions and reducing accident risk.

[0019] 5. The active suspension hydraulic control system and control method achieves continuous adjustment of suspension stiffness by using independent hydraulic units corresponding to each of the four wheels and independent oil supply to the rodless and rod chambers of the dual-chamber hydraulic cylinder. This enhances the roll suppression capability during vehicle steering by 30% and improves handling stability. At the same time, the distributed design allows each hydraulic unit to be disassembled and maintained independently, reducing maintenance costs and improving troubleshooting efficiency compared to centralized hydraulic systems. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the multi-dimensional perception module process of the present invention; Figure 2 This is a schematic diagram of the intelligent control unit process of the present invention; Figure 3 This is a schematic diagram of the independent hydraulic unit process of the present invention; Figure 4 This is a schematic diagram of the central energy storage array process of the present invention; Figure 5 This is a schematic diagram of the hierarchical fault-tolerant module of the present invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Please see Figures 1-5 An active suspension hydraulic control system includes a multi-dimensional sensing module, an intelligent control unit, a distributed hydraulic actuation module, and a hierarchical fault-tolerant module; The multi-dimensional perception module includes millimeter-wave radar, an inertial measurement unit (IMU) located at the center of gravity of the vehicle body, a wheel six-component force sensor integrated into the wheel hub bearing, and a laser positioning vehicle attitude sensor. The intelligent control unit is a dual-core heterogeneous processor consisting of an FPGA and an ARM Cortex-A9. The FPGA is used for sensor data preprocessing, and the ARM is used to run the road condition recognition model and the improved MPC algorithm. The optimization objectives of the improved MPC algorithm are to minimize the vertical acceleration of the vehicle body, minimize the fluctuation of wheel ground force, and minimize hydraulic energy consumption. The distributed hydraulic actuator module includes independent hydraulic units corresponding to each of the four wheels and a central energy storage array with three pressure ranges. Each independent hydraulic unit consists of a miniature variable piston pump, a two-stage electro-hydraulic proportional valve, and a dual-chamber hydraulic cylinder. The hierarchical fault-tolerant module includes a hardware redundancy unit and a strategy library with three preset fault-tolerant modes; the multi-dimensional perception module is connected to the intelligent control unit and the hierarchical fault-tolerant module respectively via Ethernet / TSN bus. The intelligent control unit outputs control commands to the distributed hydraulic actuation module, and the hierarchical fault-tolerant module feeds back fault-tolerant commands to the intelligent control unit. By employing a collaborative architecture comprised of a multi-dimensional perception module, an intelligent control unit, a distributed hydraulic actuation module, and a hierarchical fault-tolerant module, this system overcomes the limitations of traditional active suspension systems that rely on "single perception, centralized control, and passive fault tolerance." The multi-dimensional perception module utilizes a dual-dimensional data acquisition logic of pre-aiming and real-time processing, with millimeter-wave radar capturing road surface features ahead to avoid the lag in post-event adjustments inherent in existing systems. The intelligent control unit's dual-core heterogeneous design enables parallel and efficient computation of "data processing" and "decision generation," resolving the performance bottleneck of a single processor under multitasking. The distributed hydraulic actuation module combines independent units with hierarchical energy storage to balance control accuracy and energy consumption optimization. The hierarchical fault-tolerant module constructs a complete hardware and software collaborative guarantee, addressing the shortcomings of existing systems that rely solely on hardware redundancy for fault tolerance. All four modules achieve 10ms-level synchronous communication via an Ethernet / TSN bus, ensuring real-time and reliable data transmission.

[0023] In a preferred embodiment, the rodless chamber of the dual-chamber hydraulic cylinder has a diameter of 90mm, a rod chamber diameter of 60mm, and a stroke of 250mm. The rodless chamber and the rod chamber are supplied with oil independently, and the suspension stiffness is continuously adjustable through differential pressure control. The differentiated chamber diameter design of the dual-chamber hydraulic cylinder is based on the principle of force balance. The larger diameter of the rodless chamber ensures vertical load-bearing capacity, while the smaller diameter of the rod chamber improves adjustment sensitivity. The 250mm stroke can cover the suspension extension and retraction requirements under most road conditions. Compared with existing single-chamber cylinders or fixed-diameter dual-chamber cylinders, the independent oil supply differential pressure control method can achieve continuous adjustment of suspension stiffness from 0-50kN / m by adjusting the pressure difference between the two chambers, avoiding the jerking feeling of traditional stiffness graded adjustment.

[0024] In a preferred embodiment, the three accumulators of the central energy storage array correspond to pressure ranges of 5-15MPa, 15-25MPa, and 25-35MPa, with volumes of 5L, 8L, and 12L respectively. A pressure monitoring unit is configured to collect pressure data of each accumulator in real time to control the accumulator switching valve group to achieve automatic switching of pressure ranges. The pressure range division is based on the hydraulic demand distribution under actual vehicle operating conditions. The 5-15MPa low pressure range is suitable for smooth road cruising conditions, the 15-25MPa medium pressure range corresponds to lightly bumpy roads, and the 25-35MPa high pressure range is for heavy bumpy or emergency braking conditions. Different volume designs match the energy demand frequency of each pressure range. The 8L volume in the medium pressure range takes into account both usage frequency and energy storage capacity. The pressure monitoring unit uses a pressure sensor with an accuracy of ±0.5%FS, which, together with the electromagnetic reversing valve group, achieves range switching within 20ms. Compared with the existing single accumulator design, the energy recovery efficiency is improved by more than 50%, and the operating time of the hydraulic pump under medium and low load conditions increases from 40% to 70%, reducing energy consumption.

[0025] In a preferred embodiment, the two-stage electro-hydraulic proportional valve includes a primary flow coarse adjustment valve and a secondary flow fine adjustment valve, with a total response time ≤8ms, and is used to precisely control the oil inlet and outlet flow of the dual-chamber hydraulic cylinder. The two-stage valve control design employs a "coarse adjustment + fine adjustment" flow control logic. The first-stage coarse adjustment valve uses a high-flow proportional valve (rated flow ≥ 50L / min) to achieve rapid filling and discharging of the hydraulic cylinder. The second-stage fine adjustment valve uses a high-precision servo valve (control accuracy ±1%) to ensure the precision of flow regulation. Compared to traditional single-stage valve control (response time 20-30ms), the total response time of ≤8ms allows the suspension to quickly track control commands. In sudden road conditions (such as driving over a 100mm bump), the suspension extension and retraction adjustment can be completed 50ms in advance, reducing the peak vertical acceleration of the vehicle body by 45%. At the same time, the two-stage valves work together to reduce the adjustment contradiction between high flow and high precision in single-stage valves, extending the valve assembly service life by up to 20%.

[0026] In a preferred embodiment, the miniature variable displacement piston pump has a displacement of 5-20 mL / r and a maximum output pressure of 35 MPa, and is used to provide pressure-adjustable hydraulic power to an independent hydraulic unit. The displacement adjustment range of the miniature variable displacement piston pump adapts to the flow requirements of different working conditions. Under low-speed and bumpy road conditions, a small displacement of 5-10 mL / r is used to reduce energy consumption; when adjusting urgently at high speed, it switches to a large displacement of 15-20 mL / r to ensure sufficient power. The maximum output pressure of 35 MPa meets the hydraulic requirements of high-load working conditions (such as a fully loaded vehicle going over potholes). Compared with a fixed displacement pump, the variable displacement pump can adjust the output in real time according to the control command. Under smooth road conditions, energy consumption is reduced by more than 30%. The pump body is made of lightweight alloy material, which is 15% lighter than traditional pump bodies, making it easy to integrate into an independent hydraulic unit near the wheels, reducing pipeline length and pressure loss.

[0027] In a preferred embodiment, the improved MPC algorithm presets 5 steps of prediction time domain and 3 steps of control time domain, and dynamically adjusts the optimization target weights according to the road condition type output by the road condition identification model: energy consumption optimization weight ≥ 0.4 under smooth road conditions, and ride comfort optimization weight ≥ 0.6 under severely bumpy road conditions. The 10ms prediction time domain step can cover road surface changes within 50ms, and the 3-step control time domain ensures rolling optimization of control commands, avoiding the algorithm getting trapped in local optima. The road condition recognition model achieves over 98% recognition accuracy for four types of road conditions by combining road surface contour data from millimeter-wave radar with a support vector machine algorithm. Dynamic weight adjustment enables the system to achieve performance balance under different operating conditions: on smooth roads, the high-energy-consumption weight reduces the load on the hydraulic pump, reducing fuel consumption by 0.3-0.5L per 100km; on heavily bumpy roads, the high-smoothness weight prioritizes suppressing vehicle body vibration, reducing the perceived bumpiness for passengers by 50%. Compared to the fixed-weight MPC algorithm, the improved algorithm improves the vehicle's overall performance score by 25%-30%. In a preferred embodiment, the three-level fault-tolerant mode is as follows: the first level of fault tolerance uses a federated Kalman filter data fusion algorithm to compensate for fault data; the second level of fault tolerance uses a pseudo-inverse torque distribution algorithm to distribute the control torque of the fault unit to the other three independent hydraulic units; and the third level of fault tolerance uses a ceiling damping semi-active control algorithm to adjust the suspension damping characteristics. The three-level fault-tolerant mode covers the entire chain of failure scenarios from sensors to actuators. Level 1 fault tolerance uses federated Kalman filtering to fuse multi-source data such as IMU and vehicle attitude sensors, eliminating outliers from faulty sensors and ensuring data accuracy is maintained above 95%. Level 2 fault tolerance's pseudo-inverse torque distribution can redistribute the control torque of the other three units when a single hydraulic unit fails, keeping the vehicle roll and pitch angles within ±3°, far exceeding the mechanical support accuracy after existing system failures. Level 3 fault tolerance's ceiling damping control adjusts the damping from 0.2 to 2.0 Ns / m by regulating the accumulator release pressure, maintaining basic vehicle driving stability. Compared to the existing "failure-is-degradation" fault tolerance method, this mode improves driving safety by more than 60% under system failure.

[0028] In a preferred embodiment, the hardware redundancy unit configures a backup solenoid directional valve and a pressure sensor for each independent hydraulic unit. The backup solenoid directional valve is of the same model as the main solenoid directional valve and is used to switch the oil circuit in case of failure. The hardware redundancy unit adopts a "primary and backup from the same source" design. The backup solenoid directional valve is selected from the same model as the main valve (such as Vickers DG4V-3) to ensure that the oil circuit characteristics are consistent after switching, avoiding control deviations caused by valve differences. The pressure sensor adopts a dual-channel acquisition design, with the primary and backup sensors synchronously acquiring pressure data and performing cross-verification. When the error of the primary sensor exceeds ±2%, it automatically switches to the backup sensor. The hardware redundancy and software fault-tolerant algorithm work together to complete the backup valve switching within 20ms when the primary valve fails, and the oil circuit pressure fluctuation is controlled within ±0.5MPa to ensure the continuity and stability of suspension control.

[0029] In a preferred embodiment, the transmission cycle of the Ethernet / TSN bus is 10ms, which is used to realize synchronous data transmission between the multi-dimensional sensing module, the intelligent control unit, and the hierarchical fault-tolerant module. The Ethernet / TSN bus supports time-sensitive networking protocols and ensures that the time deviation of data transmission between modules is ≤1ms through a precise time synchronization mechanism (such as IEEE 802.1AS), meeting the real-time requirements of active suspension. The 10ms transmission cycle matches the algorithm operation cycle of the intelligent control unit, realizing closed-loop control of "data acquisition-processing-decision-execution". The bus adopts a dual-redundancy design. When the main bus fails, it automatically switches to the backup bus with a switching time of ≤5ms, avoiding system loss of control due to data transmission interruption. Compared with the traditional CAN bus (transmission cycle 20-50ms), the TSN bus improves the real-time performance and reliability, providing communication guarantee for the rapid response of the system.

[0030] A control method for an active suspension hydraulic control system includes the following steps: S1. Pre-aiming perception and status acquisition: The multi-dimensional perception module synchronously acquires road surface three-dimensional contour, vehicle motion status, wheel load and body posture data. After signal conditioning, the data is transmitted through Ethernet / TSN bus. The signal conditioning unit uses a second-order low-pass filter (cutoff frequency 50Hz) to remove sensor noise and ensure that the data signal-to-noise ratio is ≥40dB.

[0031] S2. Road Condition Recognition and Control Decision: The FPGA performs Kalman filtering and time synchronization preprocessing on the data. The ARM Cortex-A9 calls the road condition recognition model to determine the road condition type. The improved MPC algorithm solves the optimal control quantity and generates control instructions. The parallel processing capability of the FPGA makes the preprocessing delay of multi-sensor data ≤5ms. The improved MPC algorithm of the ARM completes the calculation of the optimal solution within 2ms through the quadratic programming solver.

[0032] S3. Distributed execution and energy consumption optimization: The distributed hydraulic execution module receives control commands and adjusts the hydraulic pump pressure and proportional valve opening. The central energy storage array realizes pressure matching energy storage and release. The pressure matching energy storage of the central energy storage array enables energy recovery efficiency of 55%-65%, reducing the load on the hydraulic pump.

[0033] S4. Graded fault tolerance and safety assurance: The graded fault tolerance module monitors the working status of components, activates the corresponding fault tolerance mode according to the fault type, feeds back fault tolerance instructions to the intelligent control unit and triggers alarms. The status monitoring cycle of the graded fault tolerance module is 5ms, which captures component abnormalities in real time and has a fault response time of ≤10ms. By collecting road condition data in advance through S1, determining the road to be slightly bumpy through S2 and generating a control command to extend the suspension by 50mm through S3, executing the command to allow the suspension to buffer the impact in advance, and simultaneously monitoring the status of each component through S4, the entire process takes ≤15ms, which significantly improves road condition adaptability and driving smoothness compared to the 20-30ms response time of the existing system.

[0034] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0035] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An active suspension hydraulic control system characterized by, The application relates to a multi-dimensional perception module, an intelligent control unit, a distributed hydraulic execution module and a hierarchical fault-tolerant module. The multi-dimensional perception module comprises a millimeter wave radar, an inertial measurement unit (IMU) arranged at a vehicle body center of mass, a wheel six-component force sensor integrated in a hub bearing and a laser positioning vehicle body posture sensor. The intelligent control unit is a dual-core heterogeneous processor composed of an FPGA and an ARM Cortex-A9, wherein the FPGA is used for sensor data preprocessing, the ARM is used for running a road condition recognition model and an improved MPC algorithm, and the optimization target of the improved MPC algorithm is minimization of vehicle body vertical acceleration, minimization of wheel ground force fluctuation and minimization of hydraulic energy consumption. The distributed hydraulic execution module comprises four independent hydraulic units corresponding to four wheels and a three-pressure-interval central energy storage array, each independent hydraulic unit is composed of a micro variable plunger pump, a two-stage electro-hydraulic proportional valve and a double-cavity hydraulic cylinder. The hierarchical fault-tolerant module comprises a hardware redundancy unit and a strategy library of a preset three-level fault-tolerant mode; the multi-dimensional perception module is connected with the intelligent control unit and the hierarchical fault-tolerant module through Ethernet / TSN buses, the intelligent control unit outputs control instructions to the distributed hydraulic execution module, and the hierarchical fault-tolerant module feeds back fault-tolerant instructions to the intelligent control unit.

2. The active suspension hydraulic control system according to claim 1, characterized by: The double-cavity hydraulic cylinder has a 90mm diameter of a rodless cavity, a 60mm diameter of a rod cavity and a 250mm stroke, the rodless cavity and the rod cavity are independently supplied with oil, and the continuous adjustment of suspension stiffness is realized through differential pressure control.

3. The active suspension hydraulic control system of claim 1, wherein: The three accumulators of the central energy storage array correspond to 5-15MPa, 15-25MPa and 25-35MPa pressure intervals, have volumes of 5L, 8L and 12L in sequence, and are provided with pressure monitoring units for collecting pressure data of the accumulators in real time, so that the pressure interval automatic switching is realized through an accumulator switching valve group.

4. The active suspension hydraulic control system of claim 1, wherein: The two-stage electro-hydraulic proportional valve comprises a primary flow coarse adjustment valve and a secondary flow fine adjustment valve, and has a total response time of less than or equal to 8ms, and is used for accurately controlling the oil inlet and outlet amounts of the double-cavity hydraulic cylinder.

5. The active suspension hydraulic control system of claim 1, wherein: The micro variable plunger pump has a displacement of 5-20mL / r and a maximum output pressure of 35MPa, and is used for providing the independent hydraulic unit with adjustable hydraulic power.

6. The active suspension hydraulic control system of claim 1, wherein: The improved MPC algorithm presets a 5-step prediction time domain and a 3-step control time domain, and dynamically adjusts the optimization target weight according to the road condition type output by the road condition recognition model: the energy consumption optimization weight is greater than or equal to 0.4 under the flat road condition, and the smoothness optimization weight is greater than or equal to 0.6 under the severe jolt road condition.

7. The active suspension hydraulic control system of claim 1, wherein: The three-level fault-tolerant mode is as follows: the first-level fault tolerance adopts a federal Kalman filter data fusion algorithm to compensate for fault data, the second-level fault tolerance adopts a pseudo-inverse torque distribution algorithm to distribute the control torque of the fault unit to the other three independent hydraulic units, and the third-level fault tolerance adopts a skyhook damping semi-active control algorithm to adjust the suspension damping characteristics.

8. The active suspension hydraulic control system of claim 1, wherein: The hardware redundancy unit is provided with a standby electromagnetic reversing valve and a pressure sensor for each independent hydraulic unit, the standby electromagnetic reversing valve is identical with the main electromagnetic reversing valve in type, and is used for switching the oil way in case of fault.

9. The active suspension hydraulic control system of claim 1, wherein: The transmission cycle of the Ethernet / TSN bus is 10 ms, and is used for realizing synchronous data transmission between the multi-dimensional perception module and the intelligent control unit and the hierarchical fault-tolerant module.

10. A control method of an active suspension hydraulic control system, characterized by, The method comprises the following steps: S1, pre-look perception and state acquisition: the multi-dimensional perception module synchronously collects road surface three-dimensional profile, vehicle motion state, wheel load and vehicle body posture data, and transmits the data through the Ethernet / TSN bus after signal conditioning; S2, road condition identification and control decision: the FPGA performs Kalman filtering and time synchronization preprocessing on the data, the ARM Cortex-A9 calls a road condition identification model to determine the road condition type, and an improved MPC algorithm is used to solve the optimal control quantity and generate a control instruction; S3, distributed execution and energy consumption optimization: the distributed hydraulic execution module receives the control instruction, adjusts the hydraulic pump pressure and the proportional valve opening degree, and the central energy storage array realizes pressure matching energy storage and energy release; S4, hierarchical fault tolerance and safety guarantee: the hierarchical fault-tolerant module monitors the working state of the components, starts the corresponding fault-tolerant mode according to the fault type, feeds back the fault-tolerant instruction to the intelligent control unit and triggers the alarm.

Images