Intelligent hydraulic interconnection suspension system and control method thereof

Abstract

The invention discloses an intelligent hydraulic interconnected suspension system and a control method thereof, and belongs to the technical field of vehicle suspensions.The intelligent hydraulic interconnected suspension system comprises a hydraulic assembly, an adjusting assembly and an energy storage assembly, and interconnected hydraulic pipelines of hydraulic cylinders at the four wheel ends of a vehicle are reasonably arranged, matched with an energy accumulator, an adjustable damping valve, a control valve set and an adjusting oil cylinder; passive control, semi-active control and active control of the vehicle can be achieved, so that side-tipping resistance, pitching resistance, vertical resistance, multi-rigidity adjustment, damping stepless adjustment, vehicle body lifting, height adjustment of a front axle and a rear axle of the vehicle, rigidity active regulation and control and rigidity active regulation and control after height regulation and control of the vehicle are achieved, and the overall structure is simple and convenient to debug and maintain.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of vehicle suspension, and particularly relates to an intelligent hydraulic interconnected suspension system and a control method thereof. BACKGROUND

[0002] Suspension systems play a very important role in the safety and stability of vehicles, but the requirements of vehicle comfort and handling stability on the characteristics of vehicle suspension are conflicting. The traditional suspension system generally has the characteristics of relatively simple structure and high reliability, but as a passive suspension system, it cannot change its parameters to improve vehicle comfort or handling stability for specific road conditions, so it is only a compromise for vehicle comfort and handling stability.

[0003] Interconnected suspension refers to a suspension system that makes the independent movement of automobile wheels related according to a predetermined mechanism through mechanical or hydraulic structure. It can transmit the movement of a single wheel to other wheels and cause the corresponding change of spring force, thereby integrating the independent wheel movement into a whole and greatly changing the suspension characteristics of the vehicle. Compared with the traditional suspension, the interconnected suspension has the following characteristics. Its main advantage is that it can greatly improve the handling performance of the vehicle, such as roll resistance and pitch resistance, without compromising ride comfort.

[0004] The patent document with the patent number CN114537072A discloses an oil-gas interconnected suspension with adaptive damping and adjustable roll stiffness. The technical solution adjusts the damping characteristics of the suspension system by controlling the size of the valve aperture of the electromagnetic proportional flow control valve, and adjusts the roll stiffness of the suspension by changing the initial gas pressure of the accumulator. However, this technical solution only involves the switching process of different suspension modes under a single configuration, and cannot realize switching between multiple configurations of the suspension system.

[0005] The patent document with the patent number CN115972840A discloses a hydraulic interconnected suspension system and a control method thereof. The technical solution realizes the mutual switching of the hydraulic interconnected suspension between the anti-roll, anti-pitch and anti-vertical three configurations by combining the different states of the three reversing valves, so that the vehicle suspension system has multiple active control modes. And the method of adjusting the pressure difference between the two accumulators by driving the actuator to adjust the movement of the oil cylinder piston rod to generate active control force is simple and efficient, and can realize active force control under each configuration at a low cost. However, this technical solution does not realize the on-off of the actuator, so the vehicle cannot realize passive control, semi-active control or active control according to the motion condition. At the same time, this technical solution lacks height control of the vehicle body and adjustment of the height of the front and rear axles of the vehicle.

[0006] The technical personnel in the field are urgently needed to provide an intelligent hydraulic interconnected suspension system capable of switching different suspension modes and adjusting the height of the vehicle body and a control method thereof. SUMMARY

[0007] Therefore, the present application provides an intelligent hydraulic interconnected suspension system and a control method thereof to solve at least one of the above technical problems.

[0008] To achieve the above-mentioned purpose, the present application adopts the following technical solutions: An intelligent hydraulic interconnected suspension system comprises a hydraulic assembly, an adjusting assembly, an energy storage assembly and a driving assembly, the hydraulic assembly comprises a first oil cylinder, a second oil cylinder, a third oil cylinder and a fourth oil cylinder, the piston rods in the first oil cylinder, the second oil cylinder, the third oil cylinder and the fourth oil cylinder are connected with the spring-loaded masses of the left front wheel, the right front wheel, the left rear wheel and the right rear wheel of the vehicle respectively, and the bottoms of the first oil cylinder, the second oil cylinder, the third oil cylinder and the fourth oil cylinder are connected with the unsprung masses respectively; the adjusting assembly comprises a first reversing valve, a second reversing valve, a third reversing valve and a fourth reversing valve, the first reversing valve, the second reversing valve, the third reversing valve and the fourth reversing valve are all two-position four-way valves, the energy storage assembly comprises a first accumulator and a second accumulator, the upper chamber and the lower chamber of the first oil cylinder are switched to communicate with the first accumulator and the second accumulator through the first reversing valve; the upper chamber and the lower chamber of the second oil cylinder are switched to communicate with the first accumulator and the second accumulator through the second reversing valve; the upper chamber and the lower chamber of the third oil cylinder are switched to communicate with the first accumulator and the second accumulator through the third reversing valve; the upper chamber and the lower chamber of the fourth oil cylinder are switched to communicate with the first accumulator and the second accumulator through the fourth reversing valve; The driving assembly comprises a first actuator and a second actuator, the first actuator and the second actuator are both servo motors; the accumulator further comprises a fifth accumulator; the adjusting assembly further comprises an adjusting oil cylinder, the adjusting oil cylinder is provided with a first piston rod and a second piston rod, the first piston rod and the second piston rod slide in the adjusting oil cylinder to divide the adjusting oil cylinder into three chambers, the left side is a first chamber, the right side is a second chamber, and the middle is a third chamber, the first actuator and the second actuator are drivingly connected with the first piston rod and the second piston rod respectively; the first accumulator communicates with the first chamber, the second accumulator communicates with the second chamber, and the third chamber communicates with the fifth accumulator.

[0009] Further, the adjusting assembly further comprises a first adjustable damping valve, a second adjustable damping valve, a third adjustable damping valve, a fourth adjustable damping valve, a fifth adjustable damping valve, a sixth adjustable damping valve, a seventh adjustable damping valve and an eighth adjustable damping valve, the first adjustable damping valve is installed at the upper chamber oil outlet of the first oil cylinder, the second adjustable damping valve is installed at the lower chamber oil outlet of the first oil cylinder; The third adjustable damping valve is installed at the upper chamber oil outlet of the second oil cylinder, and the fourth adjustable damping valve is installed at the lower chamber oil outlet of the second oil cylinder; The fifth adjustable damping valve is installed at the upper chamber oil outlet of the third oil cylinder, and the sixth adjustable damping valve is installed at the lower chamber oil outlet of the third oil cylinder; The seventh adjustable damping valve is installed at the upper chamber oil outlet of the fourth oil cylinder, and the eighth adjustable damping valve is installed at the lower chamber oil outlet of the fourth oil cylinder.

[0010] Further, the energy storage assembly further comprises a third accumulator and a fourth accumulator, the adjusting assembly further comprises a fifth on-off valve and a sixth on-off valve, the fifth on-off valve and the sixth on-off valve are two-position two-way valves, the third accumulator is connected in parallel with the first accumulator and communicates with the first chamber, the fourth accumulator is connected in parallel with the second accumulator and communicates with the second chamber, the fifth on-off valve is installed at the oil outlet of the third accumulator, and the sixth on-off valve is installed at the oil outlet of the fourth accumulator.

[0011] Further, the adjusting assembly further comprises a first on-off valve, a second on-off valve, a third on-off valve, a fourth on-off valve and a seventh on-off valve, the first on-off valve, the second on-off valve, the third on-off valve, the fourth on-off valve and the seventh on-off valve are two-position two-way valves, the first on-off valve is arranged on the passage between the first reversing valve and the second reversing valve and the first accumulator, the second on-off valve is arranged on the passage between the first reversing valve and the second reversing valve and the second accumulator, the third on-off valve is arranged on the passage between the third reversing valve and the fourth reversing valve and the first accumulator, and the fourth on-off valve is arranged on the passage between the third reversing valve and the fourth reversing valve and the second accumulator.

[0012] A control method of an intelligent hydraulic interconnected suspension system, using the intelligent hydraulic interconnected suspension system, comprising a passive control method, the passive control method comprising: S1, anti-roll The controller obtains the roll angle of the vehicle during motion And the roll angle acceleration , compare them with the roll angle threshold 0 and- 0 of the vehicle and the roll angle acceleration threshold 0 and- 0 is performed; if 0 is performed; if 0 is performed; if 0 is performed; if 0, at this time the oil circuit is switched to the anti-roll mode; When the vehicle turns to the right, the first and third directional control valves are parallel oil circuit, the second and fourth directional control valves are cross oil circuit, the first cylinder upper chamber, the second cylinder lower chamber, the third cylinder upper chamber, the fourth cylinder lower chamber and the first accumulator are connected through the hydraulic pipeline, forming the first oil circuit; the first cylinder lower chamber, the second cylinder upper chamber, the third cylinder lower chamber, the fourth cylinder upper chamber and the second accumulator are connected through the hydraulic pipeline, forming the second oil circuit; due to the inertial effect, the vehicle body posture is in the state of leaning to the left, the change of the relative displacement of the vehicle body and the wheel leads to the first and third cylinders in compression state, and the second and fourth cylinders in tension state; the piston rod of the first and third cylinders moves upward, the piston rod of the second and fourth cylinders moves downward, the first cylinder upper chamber oil, the second cylinder lower chamber oil, the third cylinder upper chamber oil and the fourth cylinder lower chamber oil are extruded, the hydraulic oil in the first oil circuit is pressed to the first accumulator, the air chamber in the first accumulator is compressed, and the oil pressure in the first oil circuit rises; on the contrary, the volume of the first cylinder lower chamber, the second cylinder upper chamber, the third cylinder lower chamber and the fourth cylinder upper chamber increases, the hydraulic oil in the second oil circuit flows into the first cylinder lower chamber, the second cylinder upper chamber, the third cylinder lower chamber and the fourth cylinder upper chamber from the second accumulator, the air chamber in the second accumulator expands, the oil pressure in the second oil circuit decreases, providing a resistance moment to prevent the vehicle from leaning to the left, playing a role of anti-left leaning; ​​​​When the vehicle turns to the left, the first and third reversing valves are in parallel oil path conduction, the second and fourth reversing valves are in cross oil path conduction, the first oil cylinder upper chamber, the second oil cylinder lower chamber, the third oil cylinder upper chamber, the fourth oil cylinder lower chamber and the first accumulator are communicated through the hydraulic pipeline to form the first oil path; the first oil cylinder lower chamber, the second oil cylinder upper chamber, the third oil cylinder lower chamber, the fourth oil cylinder upper chamber and the second accumulator are communicated through the hydraulic pipeline to form the second oil path; due to the inertial effect, the vehicle body posture is in the right side tilt state, the change of the relative displacement of the vehicle body and the wheel causes the first and third oil cylinders to be in the stretching state, and the second and fourth oil cylinders to be in the compression state; the piston rod of the first and third oil cylinders moves downward, the piston rod of the second and fourth oil cylinders moves upward, the volume of the first oil cylinder upper chamber, the second oil cylinder lower chamber, the third oil cylinder upper chamber and the fourth oil cylinder lower chamber increases, the hydraulic oil of the first oil path flows into the first oil cylinder upper chamber, the second oil cylinder lower chamber, the third oil cylinder upper chamber and the fourth oil cylinder lower chamber from the first accumulator, the gas cavity of the first accumulator expands, and the oil pressure in the first oil path decreases; on the contrary, the first oil cylinder lower chamber oil, the second oil cylinder upper chamber oil, the third oil cylinder lower chamber oil and the fourth oil cylinder upper chamber oil are extruded, the hydraulic oil of the second oil path is sent to the second accumulator, the gas cavity of the second accumulator is compressed, and the oil pressure in the second oil path increases, thereby providing a resistance moment to prevent the vehicle from tilting to the right, and playing a right anti-tilt role; S2, anti-pitch The controller obtains the pitch angle of the vehicle when the vehicle is moving and the pitch angle acceleration σ, and compares them with the pitch angle threshold 0 and- 0 of the vehicle and the pitch angle acceleration threshold σ0 and-σ0 of the vehicle; if > 0 or < 0 or σ > σ0 or σ < -σ0, then the oil path switches to the anti-pitch mode at this time; When the vehicle brakes, the first and second reversing valves are parallel oil circuit, the third and fourth reversing valves are cross oil circuit, the first and second oil cylinder upper chambers, the third and fourth oil cylinder lower chambers and the first accumulator are connected by hydraulic pipeline, forming the first oil circuit; the first and second oil cylinder lower chambers, the third and fourth oil cylinder upper chambers and the second accumulator are connected by hydraulic pipeline, forming the second oil circuit; due to the inertial effect, the vehicle will nod, the body and the wheel relative displacement change causes the first and second oil cylinders to be in compression state, the third and fourth oil cylinders to be in tension state; the first and second oil cylinder piston rods move upward, the third and fourth oil cylinder piston rods move downward, the first and second oil cylinder upper chamber oil, the third and fourth oil cylinder lower chamber oil are extruded, the first oil circuit hydraulic oil is sent to the first accumulator, the first accumulator gas cavity is compressed, the first oil circuit oil pressure rises; on the contrary, the first and second oil cylinder lower chambers, the third and fourth oil cylinder upper chambers volume become larger, the second oil circuit hydraulic oil flows from the second accumulator into the first and second oil cylinder lower chambers, the third and fourth oil cylinder upper chambers, the second accumulator gas cavity expands, the second oil circuit oil pressure decreases, providing a resistance moment to prevent the vehicle from pitching, playing a role in anti-pitching; When the vehicle accelerates, the first and second reversing valves are parallel oil circuit, the third and fourth reversing valves are cross oil circuit, the first and second oil cylinder upper chambers, the third and fourth oil cylinder lower chambers and the first accumulator are connected by hydraulic pipeline, forming the first oil circuit; the first and second oil cylinder lower chambers, the third and fourth oil cylinder upper chambers and the second accumulator are connected by hydraulic pipeline, forming the second oil circuit; due to the inertial effect, the vehicle will nod, the body and the wheel relative displacement change causes the first and second oil cylinders to be in compression state, the third and fourth oil cylinders to be in tension state; the first and second oil cylinder piston rods move upward, the third and fourth oil cylinder piston rods move downward, the first and second oil cylinder upper chamber oil, the third and fourth oil cylinder lower chamber oil are extruded, the first oil circuit hydraulic oil is sent to the first accumulator, the first accumulator gas cavity is compressed, the first oil circuit oil pressure rises; on the contrary, the first and second oil cylinder lower chambers, the third and fourth oil cylinder upper chambers volume become larger, the second oil circuit hydraulic oil flows from the second accumulator into the first and second oil cylinder lower chambers, the third and fourth oil cylinder upper chambers, the second accumulator gas cavity expands, the second oil circuit oil pressure decreases, providing a resistance moment to prevent the vehicle from pitching, playing a role in anti-pitching; S3, anti-vertical The controller acquires the vertical acceleration α when the vehicle is moving, compares them with the vertical acceleration threshold α0 and -α0 of the vehicle, and switches to the anti-vertical mode if α > α0 or α < -α0; When the vehicle is subjected to a vertical impact, the first, second, third and fourth reversing valves are all parallel to the oil circuit, the first, second, third and fourth oil cylinder upper chambers and the first accumulator are connected through the hydraulic pipeline to form the first oil circuit, the first, second, third and fourth oil cylinder lower chambers and the second accumulator are connected through the hydraulic pipeline to form the second oil circuit, and the first, second, third and fourth oil cylinders are all in a compressed state due to inertia; the piston rods of the first, second, third and fourth oil cylinders move upward, the oil in the first, second, third and fourth oil cylinder upper chambers is squeezed out, the hydraulic oil in the first oil circuit is pressed into the first accumulator, the air chamber in the first accumulator is compressed, and the oil pressure in the first oil circuit rises; on the contrary, the volumes of the first, second, third and fourth oil cylinder lower chambers increase, the hydraulic oil in the second oil circuit flows from the second accumulator into the first, second, third and fourth oil cylinder lower chambers, the air chamber in the second accumulator expands, the oil pressure in the second oil circuit decreases, and a resistance moment is provided to resist the vertical movement of the vehicle, thereby playing an anti-vertical role.

[0013] Further, it also includes a semi-active control method, which comprises: S1, damping control A first adjustable damping valve is installed at the upper chamber oil outlet of the first oil cylinder, a second adjustable damping valve is installed at the lower chamber oil outlet of the first oil cylinder, a third adjustable damping valve is installed at the upper chamber oil outlet of the second oil cylinder, a fourth adjustable damping valve is installed at the lower chamber oil outlet of the second oil cylinder, a fifth adjustable damping valve is installed at the upper chamber oil outlet of the third oil cylinder, a sixth adjustable damping valve is installed at the lower chamber oil outlet of the third oil cylinder, a seventh adjustable damping valve is installed at the upper chamber oil outlet of the fourth oil cylinder, and an eighth adjustable damping valve is installed at the lower chamber oil outlet of the fourth oil cylinder; By adjusting the aperture size of each adjustable damping valve in real time, the damping characteristics of the suspension are adjusted in real time; a high-damping system requires the valve to provide greater fluid resistance, which is achieved by reducing the through-hole area of the valve; a low-damping system is achieved by increasing the through-hole area of the valve; through the measurement of the vehicle motion state by the sensor, the suspension control system adjusts the aperture size of each adjustable damping valve in real time according to the road and driving conditions, realizing adaptive damping control of the suspension.

[0014] Further, the semi-active control further comprises: S2, stiffness control The fifth on-off valve and the sixth on-off valve are opened and closed to control the opening and closing of the third accumulator and the fourth accumulator; When the fifth on-off valve and the sixth on-off valve are turned on, the first accumulator, the second accumulator, the third accumulator and the fourth accumulator are connected to the oil circuit, and the double-accumulator mode is used, at this time, the pressure of the oil circuit is smaller, and the force provided by the hydraulic system is smaller; When the fifth on-off valve and the sixth on-off valve are turned off, the first accumulator and the second accumulator are connected to the oil circuit, and the single-accumulator mode is used, at this time, the pressure of the oil circuit is larger, and the force provided by the hydraulic system is larger; The single-accumulator mode provides larger roll stiffness to the vehicle than the double-accumulator mode, and the roll angle of the vehicle body is smaller in the single-accumulator mode, so that the vehicle body is more stable, thereby realizing two-stage stiffness adjustment.

[0015] Further, the active control method comprises: S1, vehicle body lifting The oil circuit is in the anti-roll mode, and the first on-off valve, the second on-off valve, the third on-off valve, the fourth on-off valve, the fifth on-off valve, the sixth on-off valve and the seventh on-off valve are turned on; the first actuator controls the first piston rod to move left according to the controller signal, and the oil flows out of the first chamber of the adjusting oil cylinder and flows into the upper chamber of the first oil cylinder, the lower chamber of the second oil cylinder, the upper chamber of the third oil cylinder and the lower chamber of the fourth oil cylinder, thereby increasing the pressure of the first oil circuit; the second actuator controls the second piston rod to move right according to the controller signal, and the oil flows out of the second chamber of the adjusting oil cylinder and flows into the lower chamber of the first oil cylinder, the upper chamber of the second oil cylinder, the lower chamber of the third oil cylinder and the upper chamber of the fourth oil cylinder, thereby increasing the pressure of the second oil circuit; the oil flows out of the fifth accumulator and flows into the third chamber; at this time, the oil pressure in the hydraulic interconnected suspension system is increased, the force of the oil cylinder acting on the vehicle body is increased, and the vehicle body is lifted; S2, vehicle body lowering The oil circuit is in the anti-roll mode, and the first on-off valve, the second on-off valve, the third on-off valve, the fourth on-off valve, the fifth on-off valve, the sixth on-off valve and the seventh on-off valve are turned on; the first actuator controls the first piston rod to move right according to the controller signal, and the oil flows out of the upper chamber of the first oil cylinder, the lower chamber of the second oil cylinder, the upper chamber of the third oil cylinder and the lower chamber of the fourth oil cylinder and flows into the first chamber of the adjusting oil cylinder, thereby reducing the pressure of the first oil circuit; the second actuator controls the second piston rod to move left according to the controller signal, and the oil flows out of the lower chamber of the first oil cylinder, the upper chamber of the second oil cylinder, the lower chamber of the third oil cylinder and the upper chamber of the fourth oil cylinder and flows into the second chamber of the adjusting oil cylinder, thereby reducing the pressure of the second oil circuit; the oil flows out of the third chamber of the adjusting oil cylinder and flows into the fifth accumulator; at this time, the oil pressure in the hydraulic interconnected suspension system is reduced, the force of the oil cylinder acting on the vehicle body is reduced, and the overall vehicle body is lowered; S3, vehicle front axle height lifting The hydraulic circuit is in anti-roll mode, with the first, second, fifth, sixth, and seventh on / off valves open, and the third and fourth on / off valves closed. The first actuator controls the first piston rod to move left according to the controller signal, causing hydraulic fluid to flow from the first chamber of the regulating cylinder into the upper chamber of the first cylinder and the lower chamber of the second cylinder, thereby increasing the pressure in the first hydraulic circuit. The second actuator controls the second piston rod to move right according to the controller signal, causing hydraulic fluid to flow from the second chamber of the regulating cylinder into the lower chamber of the first cylinder and the upper chamber of the second cylinder, thereby increasing the pressure in the second hydraulic circuit. Hydraulic fluid from the fifth accumulator flows out and replenishes the third chamber. At this time, the hydraulic pressure in the hydraulic interconnected suspension system increases, the force exerted by the cylinders on the vehicle body increases, and the height of the vehicle's front axle is raised. S4, Vehicle rear axle height increased The hydraulic circuit is in anti-roll mode, and the third, fourth, fifth, sixth, and seventh shut-off valves are open, while the first and second shut-off valves are closed. The first actuator controls the first piston rod to move to the left according to the controller signal, and the oil flows out from the first chamber of the regulating cylinder and into the upper chamber of the third cylinder and the lower chamber of the fourth cylinder, thereby increasing the pressure in the first hydraulic circuit. The second actuator controls the second piston rod to move to the right according to the controller signal, and the oil flows out from the second chamber of the regulating cylinder and into the lower chamber of the third cylinder and the upper chamber of the fourth cylinder, thereby increasing the pressure in the second hydraulic circuit. The oil from the fifth accumulator flows out and replenishes the third chamber. At this time, the oil pressure in the hydraulic interconnected suspension system increases, the force exerted by the cylinder on the vehicle body increases, and the rear axle height of the vehicle is raised.

[0016] Furthermore, the active control method also includes: S5, Active Stiffness Control When the vehicle body tilts to the left, the first piston rod of the regulating cylinder is driven by the first actuator, moving to the left. The second piston rod is driven by the second actuator, causing the second piston rod to move to the left synchronously with the first piston rod. This keeps the volume of the third chamber of the regulating cylinder constant, allowing more oil in the first oil circuit to enter the first and third accumulators when tilting to the left, further increasing the oil pressure in the first oil circuit. However, since the oil in the first and second chambers of the regulating cylinder does not circulate, after the piston rod moves to the left, the second and fourth accumulators in the second oil circuit release more oil, filling the oil circuit and causing the oil pressure in the second oil circuit to further decrease when tilting to the left. When the vehicle body tilts to the right, the first piston rod of the adjusting cylinder is driven by the first actuator to move rightward, the second piston rod is driven by the second actuator to move rightward synchronously with the first piston rod, the volume of the third chamber of the adjusting cylinder remains unchanged, more oil in the first oil passage during right tilting enters the second accumulator and the fourth accumulator, and the oil pressure in the first oil passage during right tilting further increases; and because the oil in the first chamber and the second chamber of the adjusting cylinder does not flow into each other, after the piston rod moves rightward, the first accumulator and the third accumulator of the second oil passage during right tilting release more oil, the oil fills the oil passage, and the oil pressure in the second oil passage during right tilting further decreases; When the vehicle body tilts to the left or to the right, the active regulation of the adjusting cylinder causes the pressure difference between the upper chambers and the lower chambers of the four oil cylinders to further increase, so that a greater anti-roll moment is generated on the vehicle body, the anti-roll stiffness of the suspension is increased, and the roll angle of the vehicle body is reduced. The active regulation of the stiffness can also be regulated in the anti-pitch mode and the anti-vertical mode to achieve active control of the stiffness of the suspension.

[0017] Further, the active control method further comprises: S6, active regulation of the stiffness after height regulation The oil passage is in the anti-roll mode, and the first on-off valve, the second on-off valve, the third on-off valve, the fourth on-off valve, the fifth on-off valve, the sixth on-off valve and the seventh on-off valve are turned on. The first actuator controls the first piston rod to move leftward according to the signal of the controller, oil flows out of the first chamber of the adjusting cylinder and flows into the upper chamber of the first oil cylinder, the lower chamber of the second oil cylinder, the upper chamber of the third oil cylinder and the lower chamber of the fourth oil cylinder, thereby increasing the pressure of the first oil passage; the second actuator controls the second piston rod to move rightward according to the signal of the controller, oil flows out of the second chamber of the adjusting cylinder and flows into the lower chamber of the first oil cylinder, the upper chamber of the second oil cylinder, the lower chamber of the third oil cylinder and the upper chamber of the fourth oil cylinder, thereby increasing the pressure of the second oil passage; and oil flows out of the fifth accumulator and is supplemented to the third chamber; at this time, the oil pressure in the hydraulic interconnected suspension system increases, the force of the oil cylinder acting on the vehicle body increases, and the vehicle body is lifted. Then the first piston rod of the adjusting oil cylinder is driven by the first actuator to move left, the second piston rod is driven by the second actuator to move left synchronously with the first piston rod, the volume of the third chamber of the adjusting oil cylinder is kept unchanged, more oil in the first oil path enters the first accumulator and the third accumulator, and the oil pressure of the first oil path is further increased; and since the oil in the first chamber and the second chamber of the adjusting oil cylinder is not communicated, after the piston rod moves left, the second accumulator and the fourth accumulator of the second oil path release more oil, so that the oil fills the oil path, the oil pressure of the second oil path is further reduced, and the pressure difference between the upper chamber and the lower chamber of the four oil cylinders is further increased, so that a greater anti-roll moment is generated on the vehicle body, the anti-roll stiffness of the suspension is increased, and the roll angle of the vehicle body is reduced; the stiffness active control can also be controlled when the vehicle body is lowered, so that the stiffness of the suspension is actively controlled after the height is controlled.

[0018] The beneficial effects of the present application are: 1. By combining the information of various sensors of the vehicle to intelligently control the control valve group, the passive control mode, the semi-active control mode and the active control mode can be realized, so that the control mode can be autonomously selected according to the driving condition requirements of the vehicle, and at the same time, the multi-stage control of stiffness and damping can be realized according to the vehicle pose, so that good autonomous control mode and driving comfort are realized.

[0019] 2. The suspension system in the passive control state is applicable to basic suspension requirements, has a simple structure and low cost, but cannot actively adjust the stiffness and damping, and is applicable to good road conditions and does not require high suspension performance; the suspension system in the semi-active control state can adjust the damping force to a certain extent, has a fast response speed, and has moderate cost, and is applicable to a certain suspension adjustment capability, but does not require complete active control, for example, in a slightly bumpy road or a scene with a certain requirement for suspension response speed; the suspension system in the active control state can adjust the stiffness and damping of the suspension according to real-time input, provide optimal ride comfort and handling stability, but has high cost and large energy consumption, and is applicable to high suspension performance requirements, such as high-speed driving, intense driving or extreme road conditions.

[0020] 3. The adjusting oil cylinder structure disclosed by the present application has the characteristics of pressure regulation of different chambers, and in combination with the control mode of the intelligent hydraulic interconnected suspension system, the vehicle can realize anti-roll, anti-pitch, anti-vertical, multi-rigidity adjustment, stepless damping adjustment, vehicle body lifting, vehicle front and rear axle height adjustment functions, and the introduction of the adjusting oil cylinder enables the various control modes to have active regulation functions of height, stiffness and damping, and better driving adaptability and operation stability are realized. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed in the embodiments or prior art description. Obviously, the drawings described below are only a part of the embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.

[0022] Figure 1 It is an oil circuit schematic diagram when the intelligent hydraulic interconnected suspension system resists left tilt.

[0023] Figure 2 It is an oil circuit schematic diagram when the intelligent hydraulic interconnected suspension system is semi-active controlled.

[0024] Figure 3 It is an oil circuit schematic diagram when the intelligent hydraulic interconnected suspension system is actively controlled.

[0025] Figure 4 It is a principle diagram of adjusting the oil cylinder.

[0026] In the drawings: 1-first oil cylinder, 2-second oil cylinder, 3-third oil cylinder, 4-fourth oil cylinder, 5-first reversing valve, 6-second reversing valve, 7-third reversing valve, 8-fourth reversing valve, 9-first on-off valve, 10-second on-off valve, 11-third on-off valve, 12-fourth on-off valve, 13-fifth on-off valve, 14-sixth on-off valve, 15-seventh on-off valve, 16-first accumulator, 17-second accumulator, 18-third accumulator, 19-fourth accumulator, 20-fifth accumulator, 21-adjusting oil cylinder, 22-first actuator, 23-second actuator, 24-first adjustable damping valve, 25-second adjustable damping valve, 26-third adjustable damping valve, 27-fourth adjustable damping valve, 28-fifth adjustable damping valve, 29-sixth adjustable damping valve, 30-seventh adjustable damping valve, 31-eighth adjustable damping valve. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.

[0028] Refer to the drawings Figures 1-4The application provides a kind of intelligent hydraulic interconnection suspension system, comprising: hydraulic assembly, adjusting assembly, energy storage assembly and drive assembly, hydraulic assembly includes first oil cylinder 1, second oil cylinder 2, third oil cylinder 3 and fourth oil cylinder 4, the piston rod in first oil cylinder, second oil cylinder, third oil cylinder and fourth oil cylinder is connected with the spring load mass of the left front wheel, right front wheel, left rear wheel and right rear wheel of vehicle respectively, and the bottom of first oil cylinder, second oil cylinder, third oil cylinder and fourth oil cylinder is connected with the unsprung mass respectively;Adjusting assembly includes first reversing valve 5, second reversing valve 6, third reversing valve 7 and fourth reversing valve 8, first reversing valve 5, second reversing valve 6, third reversing valve 7 and fourth reversing valve 8 are all two-position four-way valve, energy storage assembly includes first accumulator 16 and second accumulator 17, and the upper chamber and lower chamber of first oil cylinder 1 are switched to be communicated with first accumulator 16 and second accumulator 17 by first reversing valve 5;The upper chamber and lower chamber of second oil cylinder 2 are switched to be communicated with first accumulator 16 and second accumulator 17 by second reversing valve 6;The upper chamber and lower chamber of third oil cylinder 3 are switched to be communicated with first accumulator 16 and second accumulator 17 by third reversing valve 7;The upper chamber and lower chamber of fourth oil cylinder 4 are switched to be communicated with first accumulator 16 and second accumulator 17 by fourth reversing valve 8; Drive assembly includes first actuator 22 and second actuator 23, and first actuator 22 and second actuator 23 are all servo motor;The accumulator further includes fifth accumulator 20;Adjusting assembly further includes adjusting oil cylinder 21, first piston rod and second piston rod are arranged in adjusting oil cylinder 21, and first piston rod and second piston rod slide in adjusting oil cylinder 21 and divide adjusting oil cylinder 21 into three chambers, the left side is first chamber, the right side is second chamber, and the middle is third chamber, and first actuator 22 and second actuator 23 are respectively in transmission connection with first piston rod and second piston rod;First accumulator 16 is communicated with first chamber, second accumulator 17 is communicated with second chamber, and third chamber is communicated with fifth accumulator 20.

[0029] Preferably, one embodiment, adjusting assembly further includes first adjustable damping valve 24, second adjustable damping valve 25, third adjustable damping valve 26, fourth adjustable damping valve 27, fifth adjustable damping valve 28, sixth adjustable damping valve 29, seventh adjustable damping valve 30 and eighth adjustable damping valve 31, first adjustable damping valve 24 is installed in the oil outlet of the upper chamber of first oil cylinder 1, and second adjustable damping valve 25 is installed in the oil outlet of the lower chamber of first oil cylinder 1; Third adjustable damping valve 26 is installed in the oil outlet of the upper chamber of second oil cylinder 2, and fourth adjustable damping valve 27 is installed in the oil outlet of the lower chamber of second oil cylinder 2; Fifth adjustable damping valve 28 is installed in the oil outlet of the upper chamber of third oil cylinder 3, and sixth adjustable damping valve 29 is installed in the oil outlet of the lower chamber of third oil cylinder 3; The seventh adjustable damping valve 30 is installed at the upper chamber oil outlet of the fourth oil cylinder 4, and the eighth adjustable damping valve 31 is installed at the lower chamber oil outlet of the fourth oil cylinder 4.

[0030] In a preferred embodiment, the energy storage assembly further comprises a third accumulator 18 and a fourth accumulator 19, and the adjusting assembly further comprises a fifth on-off valve 13 and a sixth on-off valve 14, the fifth on-off valve 13 and the sixth on-off valve 14 are two-position two-way valves, the third accumulator 18 is connected in parallel with the first accumulator 16 and communicates with the first chamber, the fourth accumulator 19 is connected in parallel with the second accumulator 17 and communicates with the second chamber, the fifth on-off valve 13 is installed at the oil outlet of the third accumulator 18, and the sixth on-off valve 14 is installed at the oil outlet of the fourth accumulator 19.

[0031] In a preferred embodiment, the adjusting assembly further comprises a first on-off valve 9, a second on-off valve 10, a third on-off valve 11, a fourth on-off valve 12 and a seventh on-off valve 15, the first on-off valve 9, the second on-off valve 10, the third on-off valve 11, the fourth on-off valve 12 and the seventh on-off valve 15 are two-position two-way valves, the first on-off valve 9 is arranged on the passage between the first directional valve 5, the second directional valve 6 and the first accumulator 16, the second on-off valve 10 is arranged on the passage between the first directional valve 5, the second directional valve 6 and the second accumulator 17, the third on-off valve 11 is arranged on the passage between the third directional valve 7, the fourth directional valve 8 and the first accumulator 16, and the fourth on-off valve 12 is arranged on the passage between the third directional valve 7, the fourth directional valve 8 and the second accumulator 17.

[0032] The control method of the intelligent hydraulic interconnected suspension system comprises a passive control method, a semi-active control method and an active control method.

[0033] Embodiment 1

[0034] According to the intelligent hydraulic interconnected suspension system, the pipeline connection mode of the hydraulic interconnected suspension can be switched in real time. When the vehicle is accelerating, decelerating or braking, the system can be automatically switched to the anti-pitch oil circuit, so that the vehicle pitch can be effectively inhibited; when the vehicle is turning or changing lanes, the system can be automatically switched to the anti-roll oil circuit, so that the vehicle roll can be effectively inhibited; when the vehicle is subjected to the impact and vibration in the vertical direction caused by the uneven road and external disturbance, the system can be automatically switched to the anti-vertical oil circuit. Therefore, the vehicle body posture is controlled in different driving states, so that the vehicle handling stability is improved.

[0035] The passive control method comprises: S1, anti-roll The controller acquires the roll angle of the vehicle during motion and the roll angle acceleration , and compares them with the roll angle threshold value 0 and - 0 and the roll angle acceleration threshold of the vehicle 0 and- 0, the oil circuit switches to the anti-roll mode; > 0 or < 0 or > 0 or < 0, the oil circuit switches to the anti-roll mode; When the vehicle turns to the right, the first directional valve 5 and the third directional valve 7 are parallel oil circuit, the second directional valve 6 and the fourth directional valve 8 are cross oil circuit, the first oil cylinder 1 upper chamber, the second oil cylinder 2 lower chamber, the third oil cylinder 3 upper chamber, the fourth oil cylinder 4 lower chamber and the first accumulator 16 are connected through the hydraulic pipeline, forming the first oil circuit; the first oil cylinder 1 lower chamber, the second oil cylinder 2 upper chamber, the third oil cylinder 3 lower chamber, the fourth oil cylinder 4 upper chamber and the second accumulator 17 are connected through the hydraulic pipeline, forming the second oil circuit; due to the inertia effect, the vehicle body posture is in the left side state, the change of the relative displacement of the vehicle body and the wheel causes the first oil cylinder 1 and the third oil cylinder 3 to be in the compression state, and the second oil cylinder 2 and the fourth oil cylinder 4 to be in the stretching state; the piston rod of the first oil cylinder 1 and the third oil cylinder 3 moves upward, the piston rod of the second oil cylinder 2 and the fourth oil cylinder 4 moves downward, the first oil cylinder 1 upper chamber oil, the second oil cylinder 2 lower chamber oil, the third oil cylinder 3 upper chamber oil and the fourth oil cylinder 4 lower chamber oil are extruded, the hydraulic oil in the first oil circuit is pressed to the first accumulator 16, the gas cavity in the first accumulator 16 is compressed, and the oil pressure in the first oil circuit is increased; on the contrary, the volume of the first oil cylinder 1 lower chamber, the second oil cylinder 2 upper chamber, the third oil cylinder 3 lower chamber and the fourth oil cylinder 4 upper chamber is increased, the hydraulic oil of the second oil circuit flows into the first oil cylinder 1 lower chamber, the second oil cylinder 2 upper chamber, the third oil cylinder 3 lower chamber and the fourth oil cylinder 4 upper chamber from the second accumulator 17, the gas cavity in the second accumulator 17 expands, the oil pressure in the second oil circuit decreases, providing a resistance moment to prevent the vehicle from tilting to the left, playing a role of anti-left tilt; When the vehicle turns to the left, the first and third directional control valves 5 and 7 are parallel oil passage, the second and fourth directional control valves 6 and 8 are cross oil passage, the first oil cylinder 1 upper chamber, the second oil cylinder 2 lower chamber, the third oil cylinder 3 upper chamber, the fourth oil cylinder 4 lower chamber and the first accumulator 16 are communicated through hydraulic pipeline, forming the first oil passage; the first oil cylinder 1 lower chamber, the second oil cylinder 2 upper chamber, the third oil cylinder 3 lower chamber, the fourth oil cylinder 4 upper chamber and the second accumulator 17 are communicated through hydraulic pipeline, forming the second oil passage; due to the inertia effect, the vehicle body posture is in the right side state, the change of the relative displacement of the vehicle body and the wheel causes the first and third oil cylinders 1 and 3 to be in the stretching state, and the second and fourth oil cylinders 2 and 4 to be in the compression state; the piston rod of the first and third oil cylinders 1 and 3 moves downward, the piston rod of the second and fourth oil cylinders 2 and 4 moves upward, the volume of the first oil cylinder 1 upper chamber, the second oil cylinder 2 lower chamber, the third oil cylinder 3 upper chamber and the fourth oil cylinder 4 lower chamber becomes larger, the hydraulic oil of the first oil passage flows into the first oil cylinder 1 upper chamber, the second oil cylinder 2 lower chamber, the third oil cylinder 3 upper chamber and the fourth oil cylinder 4 lower chamber from the first accumulator 16, the gas cavity of the first accumulator 16 expands, and the oil pressure in the first oil passage decreases; on the contrary, the oil liquid of the first oil cylinder 1 lower chamber, the oil liquid of the second oil cylinder 2 upper chamber, the oil liquid of the third oil cylinder 3 lower chamber and the oil liquid of the fourth oil cylinder 4 upper chamber are extruded, the hydraulic oil of the second oil passage is sent to the second accumulator 17, the gas cavity of the second accumulator 17 is compressed, and the oil pressure in the second oil passage increases, thereby providing a resistance moment to prevent the vehicle from tilting to the right, playing a role of resisting right tilt; S2, anti-pitch The controller acquires the pitch angle of the vehicle when the vehicle is moving and the pitch angle acceleration σ, and compares them with the pitch angle threshold value 0 and- 0 of the vehicle and the pitch angle acceleration threshold value σ0 and -σ0 of the vehicle; if > 0 or < 0 or σ > σ0 or σ < -σ0, the oil passage is switched to the anti-pitch mode at this time; When the vehicle brakes, the first and second reversing valves 5 and 6 are parallel, the third and fourth reversing valves 7 and 8 are cross, the first, second, third and fourth oil cylinders 1, 2, 3 and 4 are connected through the hydraulic lines, and the first and second accumulators 16 and 17 are connected through the hydraulic lines. The first and second oil cylinders 1 and 2 are in compression, and the third and fourth oil cylinders 3 and 4 are in tension. The first and second oil cylinders 1 and 2 move upward, and the third and fourth oil cylinders 3 and 4 move downward. The oil in the first and second oil cylinders 1 and 2 is pushed out, and the oil in the third and fourth oil cylinders 3 and 4 is pushed out. The oil in the first and second oil cylinders 1 and 2 is pushed into the first accumulator 16, and the oil in the third and fourth oil cylinders 3 and 4 is pushed into the second accumulator 17. The oil pressure in the first and second oil cylinders 1 and 2 is increased, and the oil pressure in the third and fourth oil cylinders 3 and 4 is decreased. The first and second accumulators 16 and 17 are compressed, and the third and fourth accumulators 17 and 18 are expanded. The vehicle is prevented from pitching, and the anti-pitching effect is achieved. When the vehicle accelerates, the first and second directional control valves 5 and 6 are parallel, the third and fourth directional control valves 7 and 8 are cross, the first and second oil cylinders 1 and 2 upper chambers, the third and fourth oil cylinders 3 and 4 lower chambers and the first accumulator 16 are connected by hydraulic lines, forming the first oil circuit; the first and second oil cylinders 1 and 2 lower chambers, the third and fourth oil cylinders 3 and 4 upper chambers and the second accumulator 17 are connected by hydraulic lines, forming the second oil circuit; due to the inertial effect, the vehicle will be lifted, the body and the wheel relative displacement changes, the first and second oil cylinders 1 and 2 are in tension, the third and fourth oil cylinders 3 and 4 are in compression; the first and second oil cylinders 1 and 2 piston rods move downward, the third and fourth oil cylinders 3 and 4 piston rods move upward, the first and second oil cylinders 1 and 2 upper chambers, the third and fourth oil cylinders 3 and 4 lower chambers volume increases, the first oil circuit hydraulic oil flows from the first accumulator 16 into the first and second oil cylinders 1 and 2 upper chambers, the third and fourth oil cylinders 3 and 4 lower chambers, the first accumulator 16 gas cavity expands, the first oil circuit oil pressure decreases; on the contrary, the first and second oil cylinders 1 and 2 lower chambers oil, the third and fourth oil cylinders 3 and 4 upper chambers oil are extruded, the second oil circuit hydraulic oil is sent to the second accumulator 17, the second accumulator 17 gas cavity is compressed, the second oil circuit oil pressure rises, thereby providing a resistance moment to prevent the vehicle from pitching, playing a role in anti-pitching; S3, Anti-Vertical The controller obtains the vertical acceleration α of the vehicle in motion, compares them with the vertical acceleration threshold α0 and -α0 of the vehicle, and if α > α0 or α < -α0, switches to the anti-vertical mode; When the vehicle is impacted vertically, the first reversing valve 5, the second reversing valve 6, the third reversing valve 7 and the fourth reversing valve 8 are all parallel to the oil circuit, the first oil cylinder 1 upper chamber, the second oil cylinder 2 upper chamber, the third oil cylinder 3 upper chamber, the fourth oil cylinder 4 upper chamber and the first accumulator 16 are connected through the hydraulic pipeline, forming the first oil circuit; the first oil cylinder 1 lower chamber, the second oil cylinder 2 lower chamber, the third oil cylinder 3 lower chamber, the fourth oil cylinder 4 lower chamber and the second accumulator 17 are connected through the hydraulic pipeline, forming the second oil circuit; due to the inertia effect, the first oil cylinder 1, the second oil cylinder 2, the third oil cylinder 3 and the fourth oil cylinder 4 are all in the compression state; the piston rod of the first oil cylinder 1, the second oil cylinder 2, the third oil cylinder 3 and the fourth oil cylinder 4 moves upward, the first oil cylinder 1 upper chamber oil, the second oil cylinder 2 upper chamber oil, the third oil cylinder 3 upper chamber oil and the fourth oil cylinder 4 upper chamber oil are extruded, the hydraulic oil in the first oil circuit is pressed into the first accumulator 16, the air chamber in the first accumulator 16 is compressed, and the oil pressure in the first oil circuit is increased; on the contrary, the volume of the first oil cylinder 1 lower chamber, the second oil cylinder 2 lower chamber, the third oil cylinder 3 lower chamber and the fourth oil cylinder 4 lower chamber is increased, the hydraulic oil of the second oil circuit flows into the first oil cylinder 1 lower chamber, the second oil cylinder 2 lower chamber, the third oil cylinder 3 lower chamber and the fourth oil cylinder 4 lower chamber from the second accumulator 17, the air chamber in the second accumulator 17 expands, the oil pressure in the second oil circuit decreases, and a resistance torque is provided to prevent the vehicle from vertically moving, thereby playing a role in resisting the vertical direction.

[0036] Embodiment 2

[0037] The semi-active control is that one or both of the damping coefficient of the suspension and the stiffness of the suspension can be adjusted within a certain range.

[0038] The semi-active control method comprises: S1, damping control A first adjustable damping valve 24 is installed at the oil outlet of the upper chamber of the first oil cylinder 1, a second adjustable damping valve 25 is installed at the oil outlet of the lower chamber of the first oil cylinder 1, a third adjustable damping valve 26 is installed at the oil outlet of the upper chamber of the second oil cylinder 2, a fourth adjustable damping valve 27 is installed at the oil outlet of the lower chamber of the second oil cylinder 2, a fifth adjustable damping valve 28 is installed at the oil outlet of the upper chamber of the third oil cylinder 3, a sixth adjustable damping valve 29 is installed at the oil outlet of the lower chamber of the third oil cylinder 3, a seventh adjustable damping valve 30 is installed at the oil outlet of the upper chamber of the fourth oil cylinder 4, and an eighth adjustable damping valve 31 is installed at the oil outlet of the lower chamber of the fourth oil cylinder 4. By adjusting the size of the aperture of each adjustable damping valve in real time, the damping characteristics of the suspension are adjusted in real time; a high damping system needs the valve to provide greater fluid resistance, which is realized by reducing the through-hole area of the valve; a low damping system is realized by increasing the through-hole area of the valve; through the measurement of the vehicle motion state by the sensor, the suspension control system adjusts the size of the aperture of each adjustable damping valve according to the road and driving conditions in real time, so as to realize the self-adaptive damping control of the suspension.

[0039] S2, Stiffness regulation

[0040] The third accumulator 18 and the fourth accumulator 19 are controlled by changing the opening and closing of the fifth on-off valve 13 and the sixth on-off valve 14; When the fifth on-off valve 13 and the sixth on-off valve 14 are turned on, the first accumulator 16, the second accumulator 17, the third accumulator 18 and the fourth accumulator 19 are connected to the oil circuit, and the double-accumulator mode is used. At this time, the pressure of the oil circuit is smaller, and the force provided by the hydraulic system is smaller; When the fifth on-off valve 13 and the sixth on-off valve 14 are turned off, the first accumulator 16 and the second accumulator 17 are connected to the oil circuit, and the single-accumulator mode is used. At this time, the pressure of the oil circuit is larger, and the force provided by the hydraulic system is larger; The single-accumulator mode provides larger roll stiffness to the vehicle than the double-accumulator mode. In the single-accumulator mode, the roll angle of the vehicle body is smaller, and the attitude of the vehicle body is more stable, thereby realizing two-stage stiffness regulation.

[0041] Embodiment 3

[0042] The active control method can realize vehicle body lifting, front and rear axle height adjustment and active stiffness regulation. The active control method comprises: S1, Vehicle body lifting The oil circuit is in the anti-roll mode, and the first on-off valve 9, the second on-off valve 10, the third on-off valve 11, the fourth on-off valve 12, the fifth on-off valve 13, the sixth on-off valve 14 and the seventh on-off valve 15 are turned on. The first actuator 22 controls the left movement of the first piston rod according to the controller signal, and the oil flows out of the first chamber of the adjusting oil cylinder 21 and flows into the upper chamber of the first oil cylinder 1, the lower chamber of the second oil cylinder 2, the upper chamber of the third oil cylinder 3 and the lower chamber of the fourth oil cylinder 4, thereby increasing the pressure of the first oil circuit. The second actuator 23 controls the right movement of the second piston rod according to the controller signal, and the oil flows out of the second chamber of the adjusting oil cylinder 21 and flows into the lower chamber of the first oil cylinder 1, the upper chamber of the second oil cylinder 2, the lower chamber of the third oil cylinder 3 and the upper chamber of the fourth oil cylinder 4, thereby increasing the pressure of the second oil circuit. The oil of the fifth accumulator 20 flows out and is supplemented to the third chamber. At this time, the oil pressure in the hydraulic interconnected suspension system is increased, the force of the oil cylinder acting on the vehicle body is increased, and the vehicle body is lifted; S2, Vehicle body lowering The oil circuit is in the anti-roll mode, and the first on-off valve 9, the second on-off valve 10, the third on-off valve 11, the fourth on-off valve 12, the fifth on-off valve 13, the sixth on-off valve 14 and the seventh on-off valve 15 are turned on; the first actuator 22 controls the first piston rod to move right according to the controller signal, and the oil flows from the upper chamber of the first oil cylinder 1, the lower chamber of the second oil cylinder 2, the upper chamber of the third oil cylinder 3 and the lower chamber of the fourth oil cylinder 4 into the first chamber of the adjusting oil cylinder 21, thereby reducing the first oil circuit pressure; the second actuator 23 controls the second piston rod to move left according to the controller signal, and the oil flows from the lower chamber of the first oil cylinder 1, the upper chamber of the second oil cylinder 2, the lower chamber of the third oil cylinder 3 and the upper chamber of the fourth oil cylinder 4 into the second chamber of the adjusting oil cylinder 21, thereby reducing the second oil circuit pressure; the oil in the third chamber of the adjusting oil cylinder 21 flows into the fifth accumulator 20; at this time, the oil pressure in the hydraulic interconnected suspension system is reduced, the force of the oil cylinder acting on the vehicle body is reduced, and the overall vehicle body is lowered; S3, the height of the front axle of the vehicle is raised The oil circuit is in the anti-roll mode, and the first on-off valve 9, the second on-off valve 10, the fifth on-off valve 13, the sixth on-off valve 14 and the seventh on-off valve 15 are turned on, and the third on-off valve 11 and the fourth on-off valve 12 are turned off; the first actuator 22 controls the first piston rod to move left according to the controller signal, and the oil flows out of the first chamber of the adjusting oil cylinder 21 and flows into the upper chamber of the first oil cylinder 1 and the lower chamber of the second oil cylinder 2, thereby increasing the first oil circuit pressure; the second actuator 23 controls the second piston rod to move right according to the controller signal, and the oil flows out of the second chamber of the adjusting oil cylinder 21 and flows into the lower chamber of the first oil cylinder 1 and the upper chamber of the second oil cylinder 2, thereby increasing the second oil circuit pressure; the oil in the fifth accumulator 20 flows out and is supplemented to the third chamber; at this time, the oil pressure in the hydraulic interconnected suspension system is increased, the force of the oil cylinder acting on the vehicle body is increased, and the height of the front axle of the vehicle is raised. S4, the height of the rear axle of the vehicle is raised The oil circuit is in the anti-roll mode, and the third on-off valve 11, the fourth on-off valve 12, the fifth on-off valve 13, the sixth on-off valve 14 and the seventh on-off valve 15 are turned on, and the first on-off valve 9 and the second on-off valve 10 are turned off; the first actuator 22 controls the first piston rod to move left according to the controller signal, and the oil flows out of the first chamber of the adjusting oil cylinder 21 and flows into the upper chamber of the third oil cylinder 3 and the lower chamber of the fourth oil cylinder 4, thereby increasing the first oil circuit pressure; the second actuator 23 controls the second piston rod to move right according to the controller signal, and the oil flows out of the second chamber of the adjusting oil cylinder 21 and flows into the lower chamber of the third oil cylinder 3 and the upper chamber of the fourth oil cylinder 4, thereby increasing the second oil circuit pressure; the oil in the fifth accumulator 20 flows out and is supplemented to the third chamber; at this time, the oil pressure in the hydraulic interconnected suspension system is increased, the force of the oil cylinder acting on the vehicle body is increased, and the height of the rear axle of the vehicle is raised.

[0043] S5, active stiffness control

[0044] When the vehicle body tilts to the left, the first piston rod of the adjusting cylinder 21 is driven by the first actuator 22, the first piston rod moves to the left, the second piston rod is driven by the second actuator 23, so that the second piston rod moves to the left synchronously with the first piston rod, the volume of the third chamber of the adjusting cylinder 21 remains unchanged, more oil in the first oil path during left tilting enters the first accumulator 16 and the third accumulator 18, and the oil pressure in the first oil path during left tilting will further increase; and because the oil in the first chamber and the second chamber of the adjusting cylinder 21 does not flow into each other, after the piston rod moves to the left, the second accumulator 17 and the fourth accumulator 19 of the second oil path during left tilting release more oil, so that the oil fills the oil path, resulting in that the oil pressure of the second oil path during left tilting will further decrease; When the vehicle body tilts to the right, the first piston rod of the adjusting cylinder 21 is driven by the first actuator 22, the first piston rod moves to the right, the second piston rod is driven by the second actuator 23, so that the second piston rod moves to the right synchronously with the first piston rod, the volume of the third chamber of the adjusting cylinder 21 remains unchanged, more oil in the first oil path during right tilting enters the second accumulator 17 and the fourth accumulator 19, and the oil pressure in the first oil path during right tilting will further increase; and because the oil in the first chamber and the second chamber of the adjusting cylinder 21 does not flow into each other, after the piston rod moves to the right, the first accumulator 16 and the third accumulator 18 of the second oil path during right tilting release more oil, so that the oil fills the oil path, resulting in that the oil pressure of the second oil path during right tilting will further decrease; When the vehicle body tilts to the left or to the right, through the active regulation of the adjusting cylinder 21, the pressure difference of the upper and lower chambers of the four oil cylinders is further increased, so that a greater anti-tilting torque is generated on the vehicle body, the anti-tilting stiffness of the suspension is increased, and the tilting angle of the vehicle body is reduced. The active regulation of the stiffness can also be regulated in the anti-pitching mode and the anti-vertical mode, so as to realize the active control of the stiffness of the suspension.

[0045] S6, active regulation of the stiffness after height regulation

[0046] The oil path is in the anti-tilting mode, and the first on-off valve 9, the second on-off valve 10, the third on-off valve 11, the fourth on-off valve 12, the fifth on-off valve 13, the sixth on-off valve 14 and the seventh on-off valve 15 are turned on; The first actuator 22 controls the left movement of the first piston rod according to the controller signal, and the oil flows out of the first chamber of the adjusting oil cylinder 21 and flows into the upper chamber of the first oil cylinder 1, the lower chamber of the second oil cylinder 2, the upper chamber of the third oil cylinder 3 and the lower chamber of the fourth oil cylinder 4, thereby increasing the first oil line pressure; the second actuator 23 controls the right movement of the second piston rod according to the controller signal, and the oil flows out of the second chamber of the adjusting oil cylinder 21 and flows into the lower chamber of the first oil cylinder 1, the upper chamber of the second oil cylinder 2, the lower chamber of the third oil cylinder 3 and the upper chamber of the fourth oil cylinder 4, thereby increasing the second oil line pressure; the oil of the fifth accumulator 20 flows out and is supplemented to the third chamber; at this time, the oil pressure in the hydraulic interconnected suspension system rises, the force of the oil cylinder acting on the vehicle body becomes larger, and the vehicle body rises; Then the first piston rod of the adjusting oil cylinder 21 is driven by the first actuator 22, the first piston rod moves left, and the second piston rod is driven by the second actuator 23 to move left synchronously with the first piston rod, keeping the volume of the third chamber of the adjusting oil cylinder 21 unchanged, so that more oil in the first oil line enters the first accumulator 16 and the third accumulator 18, and the oil pressure of the first oil line is further increased; and because the oil in the first chamber and the second chamber of the adjusting oil cylinder 21 does not flow into each other, after the piston rod moves left, the second accumulator 17 and the fourth accumulator 19 of the second oil line will release more oil, so that the oil fills the oil line, resulting in further reduction of the oil pressure of the second oil line, thereby further increasing the pressure difference between the upper and lower chambers of the four oil cylinders, so that a larger anti-roll moment is generated on the vehicle body, the anti-roll stiffness of the suspension is increased, and the roll angle of the vehicle body is reduced; the stiffness active control can also be controlled when the vehicle body is lowered, so that the stiffness of the suspension is actively controlled after the height is controlled.

[0047] Embodiment 4

[0048] Working principle of the adjusting oil cylinder 21

[0049] The adjusting oil cylinder 21 is filled with oil and is divided into three chambers by the left and right first piston rod and the second piston rod, wherein the left chamber is the first chamber, the right chamber is the second chamber, and the middle chamber is the third chamber, and the third chamber is connected with the fifth accumulator 20 through a hydraulic pipeline. The first actuator 22 is a servo motor, which is connected with the first piston rod of the adjusting oil cylinder 21 through a ball screw mechanism and drives the first piston rod to move linearly. The second actuator 23 is a servo motor, which is connected with the second piston rod of the adjusting oil cylinder 21 through a ball screw mechanism and drives the second piston rod to move linearly.

[0050] The first actuator 22 can control the left and right movement of the first piston rod according to the signal of the controller, thereby controlling the inflow and outflow of oil in the first chamber. The second actuator 23 can control the left and right movement of the second piston rod according to the signal of the controller, thereby controlling the inflow and outflow of oil in the second chamber. It should be noted that the first piston rod and the second piston rod move independently left and right when controlling the height of the vehicle body; and when actively controlling the suspension stiffness, the first actuator 22 and the second actuator 23 control the first piston rod and the second piston rod to move left and right synchronously, respectively, to realize synchronous left movement or synchronous right movement of the first piston rod and the second piston rod. When adjusting the height of the vehicle body, the first actuator 22 controls the first piston rod to move left according to the signal of the controller, and the oil flows out of the first chamber of the adjusting oil cylinder 21 and flows into the upper chamber of the first oil cylinder 1, the lower chamber of the second oil cylinder 2, the upper chamber of the third oil cylinder 3 and the lower chamber of the fourth oil cylinder 4, thereby increasing the first oil passage pressure; the second actuator 23 controls the second piston rod to move right according to the signal of the controller, and the oil flows out of the second chamber of the adjusting oil cylinder 21 and flows into the lower chamber of the first oil cylinder 1, the upper chamber of the second oil cylinder 2, the lower chamber of the third oil cylinder 3 and the upper chamber of the fourth oil cylinder 4, thereby increasing the second oil passage pressure; the oil of the fifth accumulator 20 flows out and is supplemented to the third chamber; at this time, the oil pressure in the hydraulic interconnected suspension system is increased, the force of the oil cylinder acting on the vehicle body is increased, and the vehicle body is raised. At this time, the first piston rod and the second piston rod can move independently left and right.

[0051] When actively controlling the stiffness, when the vehicle body tilts to the left, the first piston rod of the adjusting oil cylinder 21 is driven by the first actuator 22, the first piston rod moves left, the second piston rod is driven by the second actuator 23, so that the second piston rod moves left synchronously with the first piston rod, the volume of the third chamber of the adjusting oil cylinder 21 remains unchanged, more oil in the first oil passage during left tilting enters the first accumulator 16 and the third accumulator 18, and the oil pressure of the first oil passage will further increase according to the working principle of the accumulator; and because the oil in the first chamber and the second chamber of the adjusting oil cylinder 21 does not flow into each other, after the piston rod moves left, the second accumulator 17 and the fourth accumulator 19 of the second oil passage will release more oil, so that the oil fills the oil passage, the oil pressure of the second oil passage will further decrease, thereby causing the pressure difference between the upper and lower chambers of the four oil cylinders to further increase, so that a greater anti-roll torque is generated on the vehicle body, the anti-roll stiffness of the suspension is increased, and the roll angle of the vehicle body is reduced. During this process, the first piston rod and the second piston rod move synchronously under the synchronous control of the first actuator 22 and the second actuator 23, respectively.

[0052] The above merely describes the specific embodiments of the present application, and the common knowledge of the specific structure and characteristics in the scheme is not described in detail. It should be noted that, for those skilled in the art, without departing from the structure of the present application, a number of modifications and improvements can be made, which should also be considered as the protection scope of the present application, and these will not affect the effect and practicality of the present application. The protection scope of the present application should be subject to the content of its claims, and the specific implementation mode and the like in the description can be used to explain the content of the claims.

[0053] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same and similar parts between the various embodiments can be referred to each other. For the device disclosed by the embodiments, since it corresponds to the method disclosed by the embodiments, the description is relatively simple, and the related parts can be referred to the method part.

[0054] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to the embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An intelligent hydraulic interconnected suspension system, characterized in that, include: The system comprises a hydraulic assembly, an adjustment assembly, an energy storage assembly, and a drive assembly. The hydraulic assembly includes a first cylinder (1), a second cylinder (2), a third cylinder (3), and a fourth cylinder (4). The piston rods of the first cylinder (1), second cylinder (2), third cylinder (3), and fourth cylinder (4) are respectively connected to the sprung masses of the left front wheel, right front wheel, left rear wheel, and right rear wheel of the vehicle. The bottoms of the first cylinder (1), second cylinder (2), third cylinder (3), and fourth cylinder (4) are respectively connected to the unsprung masses. The adjustment assembly includes a first directional valve (5), a second directional valve (6), a third directional valve (7), and a fourth directional valve (8). The first directional valve (5), second directional valve (6), third directional valve (7), and fourth directional valve (8) are respectively connected to the unsprung masses. All are two-position four-way valves. The energy storage component includes a first accumulator (16) and a second accumulator (17). The upper and lower chambers of the first cylinder (1) are switched to be connected to the first accumulator (16) and the second accumulator (17) through the first reversing valve (5). The upper and lower chambers of the second cylinder (2) are switched to be connected to the first accumulator (16) and the second accumulator (17) through the second reversing valve (6). The upper and lower chambers of the third cylinder (3) are switched to be connected to the first accumulator (16) and the second accumulator (17) through the third reversing valve (7). The upper and lower chambers of the fourth cylinder (4) are switched to be connected to the first accumulator (16) and the second accumulator (17) through the fourth reversing valve (8). The drive assembly includes a first actuator (22) and a second actuator (23), both of which are servo motors; the accumulator also includes a fifth accumulator (20); the adjustment assembly also includes an adjustment cylinder (21), in which a first piston rod and a second piston rod are provided, the first piston rod and the second piston rod slide in the adjustment cylinder (21) to divide the adjustment cylinder (21) into three chambers, the left side being the first chamber, the right side being the second chamber, and the middle being the third chamber, the first actuator (22) and the second actuator (23) being connected to the first piston rod and the second piston rod respectively; the first accumulator (16) is connected to the first chamber, the second accumulator (17) is connected to the second chamber, and the third chamber is connected to the fifth accumulator (20).

2. The intelligent hydraulic interconnected suspension system according to claim 1, characterized in that, The adjustment assembly further includes a first adjustable damping valve (24), a second adjustable damping valve (25), a third adjustable damping valve (26), a fourth adjustable damping valve (27), a fifth adjustable damping valve (28), a sixth adjustable damping valve (29), a seventh adjustable damping valve (30), and an eighth adjustable damping valve (31). The first adjustable damping valve (24) is installed at the upper chamber outlet of the first oil cylinder (1), and the second adjustable damping valve (25) is installed at the lower chamber outlet of the first oil cylinder (1). The third adjustable damping valve (26) is installed at the upper chamber oil outlet of the second oil cylinder (2), and the fourth adjustable damping valve (27) is installed at the lower chamber oil outlet of the second oil cylinder (2). The fifth adjustable damping valve (28) is installed at the upper chamber oil outlet of the third oil cylinder (3), and the sixth adjustable damping valve (29) is installed at the lower chamber oil outlet of the third oil cylinder (3). The seventh adjustable damping valve (30) is installed at the upper chamber oil outlet of the fourth oil cylinder (4), and the eighth adjustable damping valve (31) is installed at the lower chamber oil outlet of the fourth oil cylinder (4).

3. The intelligent hydraulic interconnected suspension system according to claim 2, characterized in that, The energy storage assembly further includes a third accumulator (18) and a fourth accumulator (19). The regulating assembly further includes a fifth shut-off valve (13) and a sixth shut-off valve (14). The fifth shut-off valve (13) and the sixth shut-off valve (14) are two-position two-way valves. The third accumulator (18) is connected in parallel with the first accumulator (16) and communicates with the first chamber. The fourth accumulator (19) is connected in parallel with the second accumulator (17) and communicates with the second chamber. The fifth shut-off valve (13) is installed at the oil outlet of the third accumulator (18), and the sixth shut-off valve (14) is installed at the oil outlet of the fourth accumulator (19).

4. The intelligent hydraulic interconnected suspension system according to claim 3, characterized in that, The regulating assembly further includes a first on / off valve (9), a second on / off valve (10), a third on / off valve (11), a fourth on / off valve (12), and a seventh on / off valve (15). The first on / off valve (9), the second on / off valve (10), the third on / off valve (11), the fourth on / off valve (12), and the seventh on / off valve (15) are two-position two-way valves. The first on / off valve (9) is located in the passage between the first reversing valve (5) and the second reversing valve (6) and the first accumulator (16). The second on / off valve (10) is located in the passage between the first reversing valve (5) and the second reversing valve (6) and the second accumulator (17). The third on / off valve (11) is located in the passage between the third reversing valve (7) and the fourth reversing valve (8) and the first accumulator (16). The fourth on / off valve (12) is located in the passage between the third reversing valve (7) and the fourth reversing valve (8) and the second accumulator (17). It also includes a drive assembly, which includes a first actuator (22) and a second actuator (23), both of which are servo motors; the energy storage unit also includes a fifth energy storage unit (20); the adjustment assembly also includes an adjustment cylinder (21), which is provided with a first piston rod and a second piston rod. The first piston rod and the second piston rod slide in the adjustment cylinder (21) to divide the adjustment cylinder (21) into three chambers: the left side is the first chamber, the right side is the second chamber, and the middle is the third chamber. The first actuator (22) and the second actuator (23) are respectively connected to the first piston rod and the second piston rod in a transmission connection; the first energy storage unit (16) and the third energy storage unit (18) are connected to the first chamber, the second energy storage unit (17) and the fourth energy storage unit (19) are connected to the second chamber, and the third chamber is connected to the fifth energy storage unit (20).

5. A control method for an intelligent hydraulic interconnected suspension system, using the intelligent hydraulic interconnected suspension system described in any one of claims 1-4, characterized in that, This includes a passive control method, which comprises: S1, Anti-roll The controller acquires the roll angle of the vehicle during movement. and roll acceleration Compare them with the vehicle's roll angle threshold. 0 and - 0 and the vehicle's roll angle acceleration threshold 0 and - Compare with 0; if > 0 or <- 0 or > 0 or <- If the value is 0, the oil circuit switches to anti-roll mode. When the vehicle turns to the right, the first reversing valve (5) and the third reversing valve (7) are connected in parallel oil circuits, and the second reversing valve (6) and the fourth reversing valve (8) are connected in cross oil circuits. The upper chamber of the first cylinder (1), the lower chamber of the second cylinder (2), the upper chamber of the third cylinder (3), the lower chamber of the fourth cylinder (4), and the first accumulator (16) are connected through hydraulic lines to form the first oil circuit. The lower chamber of the first cylinder (1), the upper chamber of the second cylinder (2), the lower chamber of the third cylinder (3), the upper chamber of the fourth cylinder (4), and the second accumulator (17) are connected through hydraulic lines to form the second oil circuit. Due to inertia, the vehicle body is tilted to the left. The change in the relative displacement of the vehicle body and the wheels causes the first cylinder (1) and the third cylinder (3) to be in a compressed state, and the second cylinder (2) and the fourth cylinder (4) to be in a stretched state. The piston rods of the first cylinder (1) and the third cylinder (3) move upward. The piston rods of the second cylinder (2) and the fourth cylinder (4) move downwards, and the oil in the upper chamber of the first cylinder (1), the lower chamber of the second cylinder (2), the upper chamber of the third cylinder (3), and the lower chamber of the fourth cylinder (4) are squeezed out. The hydraulic oil in the first oil circuit is pumped into the first accumulator (16), the air chamber in the first accumulator (16) is compressed, and the oil pressure in the first oil circuit increases. Conversely, the volume of the lower chamber of the first cylinder (1), the upper chamber of the second cylinder (2), the lower chamber of the third cylinder (3), and the upper chamber of the fourth cylinder (4) increases. The hydraulic oil in the second oil circuit flows from the second accumulator (17) into the lower chamber of the first cylinder (1), the upper chamber of the second cylinder (2), the lower chamber of the third cylinder (3), and the upper chamber of the fourth cylinder (4). The air chamber in the second accumulator (17) expands, and the oil pressure in the second oil circuit decreases, providing a resistance torque to prevent the vehicle from tilting to the left, thus playing a role in resisting left tilting. When the vehicle turns to the left, the first reversing valve (5) and the third reversing valve (7) are connected in parallel oil circuits, and the second reversing valve (6) and the fourth reversing valve (8) are connected in cross oil circuits. The upper chamber of the first cylinder (1), the lower chamber of the second cylinder (2), the upper chamber of the third cylinder (3), the lower chamber of the fourth cylinder (4), and the first accumulator (16) are connected through hydraulic lines to form the first oil circuit. The lower chamber of the first cylinder (1), the upper chamber of the second cylinder (2), the lower chamber of the third cylinder (3), the upper chamber of the fourth cylinder (4), and the second accumulator (17) are connected through hydraulic lines to form the second oil circuit. Due to inertia, the vehicle body is tilted to the right. The change in the relative displacement of the vehicle body and the wheels causes the first cylinder (1) and the third cylinder (3) to be in a stretched state, and the second cylinder (2) and the fourth cylinder (4) to be in a compressed state. The piston rods of the first cylinder (1) and the third cylinder (3) move downwards. The piston rods of the second cylinder (2) and the fourth cylinder (4) move upward, and the volume of the upper chamber of the first cylinder (1), the lower chamber of the second cylinder (2), the upper chamber of the third cylinder (3) and the lower chamber of the fourth cylinder (4) increases. The hydraulic oil in the first oil circuit flows from the first accumulator (16) into the upper chamber of the first cylinder (1), the lower chamber of the second cylinder (2), the upper chamber of the third cylinder (3) and the lower chamber of the fourth cylinder (4). The air chamber in the first accumulator (16) expands, and the oil pressure in the first oil circuit decreases. Conversely, the oil in the lower chamber of the first cylinder (1), the upper chamber of the second cylinder (2), the lower chamber of the third cylinder (3) and the upper chamber of the fourth cylinder (4) are squeezed out, and the hydraulic oil in the second oil circuit is sent to the second accumulator (17). The air chamber in the second accumulator (17) is compressed, and the oil pressure in the second oil circuit increases, thereby providing a resistance torque to prevent the vehicle from tilting to the right and playing an anti-tilt role. S2, Anti-pitch The controller acquires the pitch angle of the vehicle during its movement. And pitch acceleration σ, and compare them with the vehicle's pitch angle threshold. 0 and - The values ​​of 0 and the vehicle's pitch acceleration thresholds σ0 and -σ0 are compared; if > 0 or <- If 0 or σ > σ0 or σ < -σ0, then the hydraulic circuit switches to anti-pitch mode. When the vehicle brakes, the first reversing valve (5) and the second reversing valve (6) are connected in parallel oil circuits, and the third reversing valve (7) and the fourth reversing valve (8) are connected in cross oil circuits. The upper chamber of the first cylinder (1), the upper chamber of the second cylinder (2), the lower chamber of the third cylinder (3), the lower chamber of the fourth cylinder (4), and the first accumulator (16) are connected through hydraulic lines to form the first oil circuit; the lower chamber of the first cylinder (1), the lower chamber of the second cylinder (2), the upper chamber of the third cylinder (3), the upper chamber of the fourth cylinder (4), and the second accumulator (17) are connected through hydraulic lines to form the second oil circuit; due to inertia, the vehicle will nod, and the change in the relative displacement of the body and wheels will cause the first cylinder (1) and the second cylinder (2) to be in a compressed state, and the third cylinder (3) and the fourth cylinder (4) to be in a stretched state; the piston rods of the first cylinder (1) and the second cylinder (2) move upward, and the third cylinder (4) moves downward. When the piston rods of cylinders (3) and (4) move downward, the oil in the upper chamber of cylinder (1), cylinder (2), lower chamber of cylinder (3), and lower chamber of cylinder (4) are squeezed out, and the hydraulic oil in the first oil circuit is pumped into the first accumulator (16). The air chamber in the first accumulator (16) is compressed, and the oil pressure in the first oil circuit increases. Conversely, the volume of the lower chamber of cylinder (1), lower chamber of cylinder (2), upper chamber of cylinder (3), and upper chamber of cylinder (4) increases, and the hydraulic oil in the second oil circuit flows from the second accumulator (17) into the lower chamber of cylinder (1), lower chamber of cylinder (2), upper chamber of cylinder (3), and upper chamber of cylinder (4). The air chamber in the second accumulator (17) expands, and the oil pressure in the second oil circuit decreases, providing a resistance torque to prevent the vehicle from pitching, thus playing an anti-pitch role. When the vehicle accelerates, the first reversing valve (5) and the second reversing valve (6) are connected in parallel oil circuits, and the third reversing valve (7) and the fourth reversing valve (8) are connected in cross oil circuits. The upper chamber of the first cylinder (1), the upper chamber of the second cylinder (2), the lower chamber of the third cylinder (3), the lower chamber of the fourth cylinder (4), and the first accumulator (16) are connected through hydraulic lines to form the first oil circuit. The lower chamber of the first cylinder (1), the lower chamber of the second cylinder (2), the upper chamber of the third cylinder (3), the upper chamber of the fourth cylinder (4), and the second accumulator (17) are connected through hydraulic lines to form the second oil circuit. Due to inertia, the vehicle will lift up. The change in the relative displacement of the vehicle body and the wheels causes the first cylinder (1) and the second cylinder (2) to be in a stretched state, while the third cylinder (3) and the fourth cylinder (4) are in a compressed state. The piston rods of the first cylinder (1) and the second cylinder (2) move downwards, and the piston rods of the third cylinder (1) and the fourth cylinder (4) move downwards. When the piston rods of cylinder (3) and cylinder (4) move upward, the volume of the upper chamber of cylinder (1), the upper chamber of cylinder (2), the lower chamber of cylinder (3) and cylinder (4) increases. The hydraulic oil in the first oil circuit flows from the first accumulator (16) into the upper chamber of cylinder (1), the upper chamber of cylinder (2), the lower chamber of cylinder (3) and cylinder (4). The air chamber in the first accumulator (16) expands, and the oil pressure in the first oil circuit decreases. Conversely, the oil in the lower chamber of cylinder (1), the lower chamber of cylinder (2), the upper chamber of cylinder (3) and cylinder (4) is squeezed out. The hydraulic oil in the second oil circuit is sent to the second accumulator (17). The air chamber in the second accumulator (17) is compressed, and the oil pressure in the second oil circuit increases, thereby providing a resistance torque to prevent the vehicle from pitching and playing an anti-pitch role. S3, anti-vertical The controller acquires the vertical acceleration α of the vehicle during its movement and compares it with the vehicle's vertical acceleration thresholds α0 and -α0. If α > α0 or α < -α0, it switches to anti-vertical mode. When the vehicle is subjected to a vertical impact, the first reversing valve (5), the second reversing valve (6), the third reversing valve (7), and the fourth reversing valve (8) are all connected in parallel with the oil circuit. The upper chamber of the first cylinder (1), the upper chamber of the second cylinder (2), the upper chamber of the third cylinder (3), the upper chamber of the fourth cylinder (4), and the first accumulator (16) are connected through hydraulic lines to form the first oil circuit. The lower chamber of the first cylinder (1), the lower chamber of the second cylinder (2), the lower chamber of the third cylinder (3), the lower chamber of the fourth cylinder (4), and the second accumulator (17) are connected through hydraulic lines to form the second oil circuit. Due to inertia, the first cylinder (1), the second cylinder (2), the third cylinder (3), and the fourth cylinder (4) are all in a compressed state. The piston rods of the first cylinder (1), the second cylinder (2), the third cylinder (3), and the fourth cylinder (4) are in a compressed state. As the cylinder moves upward, the oil in the upper chamber of the first cylinder (1), the upper chamber of the second cylinder (2), the upper chamber of the third cylinder (3), and the upper chamber of the fourth cylinder (4) are squeezed out. The hydraulic oil in the first oil circuit is pumped into the first accumulator (16), the air chamber in the first accumulator (16) is compressed, and the oil pressure in the first oil circuit increases. Conversely, the volume of the lower chamber of the first cylinder (1), the lower chamber of the second cylinder (2), the lower chamber of the third cylinder (3), and the lower chamber of the fourth cylinder (4) increases. The hydraulic oil in the second oil circuit flows from the second accumulator (17) into the lower chamber of the first cylinder (1), the lower chamber of the second cylinder (2), the lower chamber of the third cylinder (3), and the lower chamber of the fourth cylinder (4). The air chamber in the second accumulator (17) expands, and the oil pressure in the second oil circuit decreases, providing a resistance torque to prevent the vehicle from moving vertically, thus playing an anti-vertical role.

6. The control method for an intelligent hydraulic interconnected suspension system according to claim 5, characterized in that, It also includes a semi-active control method, which includes: S1, Damping Control A first adjustable damping valve (24) is installed at the upper chamber outlet of the first cylinder (1), a second adjustable damping valve (25) is installed at the lower chamber outlet of the first cylinder (1), a third adjustable damping valve (26) is installed at the upper chamber outlet of the second cylinder (2), a fourth adjustable damping valve (27) is installed at the lower chamber outlet of the second cylinder (2), a fifth adjustable damping valve (28) is installed at the upper chamber outlet of the third cylinder (3), a sixth adjustable damping valve (29) is installed at the lower chamber outlet of the third cylinder (3), a seventh adjustable damping valve (30) is installed at the upper chamber outlet of the fourth cylinder (4), and an eighth adjustable damping valve (31) is installed at the lower chamber outlet of the fourth cylinder (4). The suspension damping characteristics are adjusted in real time by adjusting the orifice size of each adjustable damping valve. High-damping systems require valves to provide greater fluid resistance, which is achieved by reducing the orifice area of ​​the valves. Low-damping systems are achieved by increasing the orifice area of ​​the valves. By measuring the vehicle's motion state through sensors, the suspension control system adjusts the orifice size of each adjustable damping valve in real time according to road and driving conditions to achieve adaptive damping control of the suspension.

7. The control method for an intelligent hydraulic interconnected suspension system according to claim 6, characterized in that, The semi-active control also includes: S2, Stiffness Adjustment By changing the opening and closing of the fifth shut-off valve (13) and the sixth shut-off valve (14), the opening and closing of the third accumulator (18) and the fourth accumulator (19) can be controlled. When the fifth shut-off valve (13) and the sixth shut-off valve (14) are turned on, the first accumulator (16), the second accumulator (17), the third accumulator (18) and the fourth accumulator (19) are all connected to the oil circuit, and the dual accumulators work. At this time, the pressure in the oil circuit is smaller, and the force provided by the hydraulic system is smaller. When the fifth shut-off valve (13) and the sixth shut-off valve (14) are disconnected, the first accumulator (16) and the second accumulator (17) are connected to the oil circuit, and a single set of accumulators works. At this time, the pressure in the oil circuit is greater, and the force provided by the hydraulic system is greater. A single accumulator provides greater roll stiffness to the vehicle than a dual accumulator. In single accumulator mode, the vehicle body roll angle is smaller and the body posture is more stable, thus achieving two-stage stiffness adjustment.

8. The control method for an intelligent hydraulic interconnected suspension system according to claim 5, characterized in that, It also includes an active control method, which includes: S1, Vehicle body height increase The oil circuit is in anti-tilt mode, and the first shut-off valve (9), the second shut-off valve (10), the third shut-off valve (11), the fourth shut-off valve (12), the fifth shut-off valve (13), the sixth shut-off valve (14), and the seventh shut-off valve (15) are open; the first actuator (22) controls the first piston rod to move to the left according to the controller signal, and the oil flows out from the first chamber of the regulating cylinder (21) and into the upper chamber of the first cylinder (1), the lower chamber of the second cylinder (2), the upper chamber of the third cylinder (3), and the lower chamber of the fourth cylinder (4). The second actuator (23) controls the second piston rod to move to the right according to the controller signal, and the oil flows out from the second chamber of the regulating cylinder (21) and into the lower chamber of the first cylinder (1), the upper chamber of the second cylinder (2), the lower chamber of the third cylinder (3) and the upper chamber of the fourth cylinder (4), thereby increasing the pressure of the second oil circuit; the oil from the fifth accumulator (20) flows out and replenishes the third chamber; at this time, the oil pressure in the hydraulic interconnected suspension system increases, the force of the cylinder on the vehicle body increases, and the vehicle body rises; S2, Vehicle body lowering The oil circuit is in anti-tilt mode, and the first shut-off valve (9), the second shut-off valve (10), the third shut-off valve (11), the fourth shut-off valve (12), the fifth shut-off valve (13), the sixth shut-off valve (14), and the seventh shut-off valve (15) are open; the first actuator (22) controls the first piston rod to move to the right according to the controller signal, and the oil flows from the upper chamber of the first cylinder (1), the lower chamber of the second cylinder (2), the upper chamber of the third cylinder (3), and the lower chamber of the fourth cylinder (4) into the first chamber of the regulating cylinder (21), thereby reducing the tilt. The first oil circuit pressure is reduced; the second actuator (23) controls the second piston rod to move to the left according to the controller signal, and the oil flows from the lower chamber of the first oil cylinder (1), the upper chamber of the second oil cylinder (2), the lower chamber of the third oil cylinder (3) and the upper chamber of the fourth oil cylinder (4) into the second chamber of the regulating oil cylinder (21), thereby reducing the second oil circuit pressure; the oil flows from the third chamber of the regulating oil cylinder (21) into the fifth accumulator (20); at this time, the oil pressure in the hydraulic interconnected suspension system is reduced, the force of the oil cylinder on the body is reduced, and the overall body is lowered; S3, Increased vehicle front axle height The oil circuit is in anti-roll mode, and the first shut-off valve (9), the second shut-off valve (10), the fifth shut-off valve (13), the sixth shut-off valve (14), and the seventh shut-off valve (15) are open, while the third shut-off valve (11) and the fourth shut-off valve (12) are closed. The first actuator (22) controls the first piston rod to move to the left according to the controller signal, and the oil flows out from the first chamber of the regulating cylinder (21) and into the upper chamber of the first cylinder (1) and the lower chamber of the second cylinder (2), thereby increasing the pressure of the first oil circuit. The second actuator (23) controls the second piston rod to move to the right according to the controller signal, and the oil flows out from the second chamber of the regulating cylinder (21) and into the lower chamber of the first cylinder (1) and the upper chamber of the second cylinder (2), thereby increasing the pressure of the second oil circuit. The oil from the fifth accumulator (20) flows out and replenishes the third chamber. At this time, the oil pressure in the hydraulic interconnected suspension system increases, the force of the cylinder on the vehicle body increases, and the height of the front axle of the vehicle is raised. S4, Vehicle rear axle height increased The oil circuit is in anti-roll mode, and the third shut-off valve (11), the fourth shut-off valve (12), the fifth shut-off valve (13), the sixth shut-off valve (14) and the seventh shut-off valve (15) are open, while the first shut-off valve (9) and the second shut-off valve (10) are closed. The first actuator (22) controls the first piston rod to move to the left according to the controller signal, and the oil flows out from the first chamber of the regulating cylinder (21) and into the upper chamber of the third cylinder (3) and the lower chamber of the fourth cylinder (4), thereby increasing the pressure of the first oil circuit. The second actuator (23) controls the second piston rod to move to the right according to the controller signal, and the oil flows out from the second chamber of the regulating cylinder (21) and into the lower chamber of the third cylinder (3) and the upper chamber of the fourth cylinder (4), thereby increasing the pressure of the second oil circuit. The oil from the fifth accumulator (20) flows out and replenishes the third chamber. At this time, the oil pressure in the hydraulic interconnected suspension system increases, the force of the cylinder on the vehicle body increases, and the height of the rear axle of the vehicle is raised.

9. The control method for an intelligent hydraulic interconnected suspension system according to claim 8, characterized in that, The active control method further includes: S5, Active Stiffness Control When the vehicle body tilts to the left, the first piston rod of the regulating cylinder (21) is driven by the first actuator (22) and moves to the left. The second piston rod is driven by the second actuator (23), so that the second piston rod moves to the left in sync with the first piston rod, keeping the volume of the third chamber of the regulating cylinder (21) unchanged. This allows more oil in the first oil circuit to enter the first accumulator (16) and the third accumulator (18) when the vehicle body tilts to the left, and the oil pressure in the first oil circuit will increase further when the vehicle body tilts to the left. Since the oil in the first chamber and the second chamber of the regulating cylinder (21) does not flow between each other, after the piston rod moves to the left, the second accumulator (17) and the fourth accumulator (19) of the second oil circuit release more oil when the vehicle body tilts to the left, so that the oil circuit is filled with oil, and the oil pressure in the second oil circuit will decrease further when the vehicle body tilts to the left. When the vehicle body tilts to the right, the first piston rod of the regulating cylinder (21) is driven by the first actuator (22) and moves to the right. The second piston rod is driven by the second actuator (23), so that the second piston rod moves to the right in sync with the first piston rod, keeping the volume of the third chamber of the regulating cylinder (21) unchanged. This allows more oil in the first oil circuit to enter the second accumulator (17) and the fourth accumulator (19) when the vehicle body tilts to the right, and the oil pressure in the first oil circuit will increase further when the vehicle body tilts to the right. Since the oil in the first chamber and the second chamber of the regulating cylinder (21) does not flow between each other, after the piston rod moves to the right, the first accumulator (16) and the third accumulator (18) of the second oil circuit release more oil when the vehicle body tilts to the right, so that the oil circuit is filled with oil, and the oil pressure in the second oil circuit will decrease further when the vehicle body tilts to the right. When the vehicle body tilts to the left or right, the pressure difference between the upper and lower chambers of the four cylinders is further increased by adjusting the active control of the hydraulic cylinder (21), which generates a greater anti-roll moment on the vehicle body, increases the anti-roll stiffness of the suspension, and reduces the roll angle of the vehicle body. Active stiffness adjustment can also be performed in anti-pitch and anti-vertical modes to achieve active control of suspension stiffness.

10. The control method for an intelligent hydraulic interconnected suspension system according to claim 8, characterized in that, The active control method further includes: S6, Active stiffness control after height adjustment The oil circuit is in anti-tilt mode, and the first shut-off valve (9), the second shut-off valve (10), the third shut-off valve (11), the fourth shut-off valve (12), the fifth shut-off valve (13), the sixth shut-off valve (14) and the seventh shut-off valve (15) are open; The first actuator (22) controls the first piston rod to move to the left according to the controller signal, and the oil flows out from the first chamber of the regulating cylinder (21) and into the upper chamber of the first cylinder (1), the lower chamber of the second cylinder (2), the upper chamber of the third cylinder (3) and the lower chamber of the fourth cylinder (4), thereby increasing the pressure of the first oil circuit; the second actuator (23) controls the second piston rod to move to the right according to the controller signal, and the oil flows out from the second chamber of the regulating cylinder (21) and into the lower chamber of the first cylinder (1), the upper chamber of the second cylinder (2), the lower chamber of the third cylinder (3) and the upper chamber of the fourth cylinder (4), thereby increasing the pressure of the second oil circuit; the oil from the fifth accumulator (20) flows out and replenishes the third chamber; at this time, the oil pressure in the hydraulic interconnected suspension system increases, the force of the cylinder on the vehicle body increases, and the vehicle body rises; Then, the first piston rod of the regulating cylinder (21) is driven by the first actuator (22), and the first piston rod moves to the left. The second piston rod is driven by the second actuator (23), so that the second piston rod moves to the left synchronously with the first piston rod, keeping the volume of the third chamber of the regulating cylinder (21) unchanged, so that more oil in the first oil circuit enters the first accumulator (16) and the third accumulator (18), and the oil pressure of the first oil circuit will further increase. Since the oil in the first chamber and the second chamber of the regulating cylinder (21) does not flow between each other, after the piston rod moves to the left, the second accumulator (17) and the fourth accumulator (19) of the second oil circuit will release more oil, so that the oil fills the oil circuit, and the oil pressure of the second oil circuit will further decrease, thereby increasing the pressure difference between the upper and lower chambers of the four cylinders, which generates a larger anti-roll moment on the body, increases the anti-roll stiffness of the suspension, and reduces the body roll angle. The active stiffness control can also be adjusted when the body is lowered, realizing the active stiffness control of the suspension after height adjustment.

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