Detailed Description
Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the invention.
A control system for a suspension assembly according to an embodiment of the present invention is described below with reference to fig. 1-7.
The suspension assembly 100 according to the embodiment of the invention includes the shock absorber 2, the air spring 11, the controller and the plurality of control arms, the shock absorber 2 is connected between the vehicle body and one of the plurality of control arms, the controller is respectively linked with the shock absorber 2 and the air spring 11, the sprung mass of the whole vehicle can be borne through the shock absorber 2, and meanwhile, the wheel end vibration caused by road surface excitation can be buffered, so that the comfort of the whole vehicle is improved.
In the present application, the suspension assembly 100 includes a subframe 1, a shock absorber 2, a knuckle 3, a front upper control arm 4, a front lower control arm 5, a rear upper control arm 6, a rear lower control arm 7, a toe-in control arm 8, a stabilizer bar 9, a stabilizer bar 10, and an air spring 11.
Wherein the steering knuckle 3 is connected with wheels, the inner end of the front upper control arm 4 is connected with the auxiliary frame 1 through a bushing, and the outer end of the front upper control arm 4 is connected with the steering knuckle 3 through a bushing; the inner end of a front lower control arm 5 is connected with a subframe 1 through a bushing, the outer end of the front lower control arm 5 is connected with a steering knuckle 3 through a bushing, the inner end of a rear upper control arm 6 is connected with the subframe 1 through a bushing, the outer end of a rear upper control arm 6 is connected with the steering knuckle 3 through a bushing, the inner end of a rear lower control arm 7 is connected with the subframe 1 through a bushing, the outer end of a rear lower control arm 7 is connected with the steering knuckle 3 through a bushing, the inner end of a front beam control arm 8 is connected with the subframe 1 through a bushing, the outer end of a front beam control arm 8 is connected with the steering knuckle 3 through a bushing, the lower end of a stabilizer bar 9 is connected with a rear upper control arm 6 through a ball head, the upper end of a stabilizer bar 9 is connected with a stabilizer bar 10 through a ball head, the stabilizer bar 10 is connected with the subframe 1 through a bushing, the lower end of a damper 2 is connected with the rear lower control arm 7 through a bushing, the upper end of a damper 2 is fixedly connected with a vehicle body through a bolt, an air spring 11 is mounted between a vehicle body longitudinal beam and the lower control arm 7, the upper end of the air spring 11 is connected with the rear lower end of the rear lower control arm through a suspension pad 100, and the suspension assembly is connected with each suspension arm 100 through a suspension assembly, and the suspension assembly is connected with the suspension assembly 100.
The suspension assembly 100 has at least the following functions that firstly, the suspension assembly 100 bears the sprung mass, secondly, the suspension assembly 100 is used for controlling wheels to move smoothly according to a preset track, smooth running of the whole vehicle is ensured, vibration caused by excitation of the road to the wheels can be buffered by the suspension assembly 100, vibration of the whole vehicle is reduced, and comfort of the whole vehicle is improved.
It will be appreciated that the function of the suspension assembly 100 is achieved by the interaction of the various components that make up the suspension assembly 100, each component acting differently from the others. The front upper control arm 4, the front lower control arm 5, the rear upper control arm 6 and the rear lower control arm 7 jointly control the movement of the wheels on an XZ plane, the front beam control arm 8 controls the adjustment of the front beam of the wheels, the air spring 11 mainly plays a role in bearing the sprung mass, the air spring 11 can also adjust the height of the vehicle body by adjusting the air pressure in the air spring 11, and the shock caused by the excitation of the road surface is buffered by the main role of the shock absorber 2, so that the comfort of the whole vehicle is improved.
The shock absorber is composed of the linear motor, and according to the characteristics of the motor, the shock absorber can realize the rapid change of thrust, so that the suspension assembly also has the function of rapidly adjusting the height of the vehicle body, and the transient lifting of the whole vehicle height is realized.
The controller of the suspension assembly is used for acquiring road condition information and the current height of the vehicle body, determining the vehicle body adjusting height according to the road condition information and the current height of the vehicle body, and controlling at least one of the shock absorber and the air spring according to the vehicle body adjusting height so as to increase the ground clearance of the vehicle body and enable the vehicle to surmount the obstacle safely.
It should be noted that, the "current height of the vehicle body" may be understood as the current ground clearance height of the vehicle body, and the "vehicle body adjustment height" may be understood as the vehicle body height that needs to be adjusted based on the current height of the vehicle body when the vehicle body passes through the front road condition.
Based on the obtained road condition information and the current height of the vehicle body, the height of the vehicle body can be determined, and at least one of the shock absorber and the air spring is further controlled, so that the obstacle crossing capability of the vehicle is improved in a mode of increasing the ground clearance of the vehicle body, the road condition of the vehicle in front of the traveling direction is ensured, and the trafficability of the vehicle is ensured.
The adjusting mode of the suspension assembly comprises various modes, such as adjusting the height of the vehicle body through controlling the shock absorber, adjusting the height of the vehicle body through controlling the air spring, adjusting the height of the vehicle body through controlling the shock absorber and the air spring together, and the like.
It will be appreciated that the damper may be configured as a linear motor damper, both the damper and the air spring may be used to lift the vehicle body to adjust the height of the vehicle body, and the damper may be faster in response than the air spring, and may enable transient lifting of the vehicle body to quickly increase the height of the vehicle body in a short period of time. If the vehicle is in the process of moving, when the vehicle body height needs to be increased to meet the requirement of passing through a road section in front of the vehicle body, the vehicle body height can be adjusted in a quick lifting mode through the shock absorber, and if the vehicle is in a parking or starting stage, the vehicle body height can be adjusted only through the air spring so as to adjust the vehicle body height to a height matched with a vehicle driving mode.
The air spring is used for adjusting the height of the vehicle body by adjusting the rigidity of the air spring in a pressure adjusting mode, the height adjusting process of the air spring on the vehicle body is usually used for adjusting the vehicle body to a target height according to a driving mode, and the adjusting speed is low, so that the height of the vehicle body is usually adjusted through the air spring at the stage of selecting a vehicle to drive road conditions (such as highways, common highways, off-road roads and the like).
It can be further understood that when the road surface has a convex structure, the vehicle is easy to damage and influence the driving safety due to the risk of scraping the chassis when passing through the road section, and when the road surface has a concave structure, if the vehicle is sunk into the concave structure, the vehicle is at risk of scraping the chassis and the edge of the concave structure, thereby causing the vehicle damage and influencing the driving safety.
Therefore, the obstacle crossing capability of the vehicle needs to be improved in a mode of adjusting the height of the vehicle body (namely the ground clearance of the vehicle body), the chassis and the obstacles are prevented from being scratched, and the driving safety and reliability are improved.
According to the control system of the suspension assembly, according to the road condition information of the vehicle which is running or is about to run and the current height of the vehicle body, the height of the vehicle body can be adjusted by controlling at least one of the shock absorber and the air spring, the response speed of the shock absorber is high, the adjustment requirement of rapidly lifting the vehicle body in the running process of the vehicle can be met, and the obstacle crossing capacity and the driving safety of the vehicle are improved.
Wherein the barrier may be a raised structure or a recessed structure on the road surface, etc.
Referring to fig. 5, the above-mentioned "height of the road surface obstacle" refers to a vertical distance between the highest point of the protrusion and the road surface when the obstacle is constructed as a protrusion, and refers to a vertical distance between the lowest point of the recess and the road surface when the obstacle is constructed as a recess. That is, the traffic information refers to the absolute value of the height between the obstacle (protrusion or depression) and the road surface.
It will be appreciated that when the height value of the road obstacle is greater than the current height of the vehicle body, the vehicle will collide with the obstacle on a road section where the obstacle is present, resulting in damage to the vehicle.
In a further embodiment of the invention, the body adjustment height is determined according to the formula ΔH=H2-H. Wherein DeltaH is the height of the vehicle body, H1 is the height of the road obstacle, and H is the current height of the vehicle body.
Δh is a height parameter that needs to be adjusted for the vehicle body when passing through a road section where an obstacle exists without collision of the vehicle body, and when the vehicle body is adjusted upward by the damper Δh, the vehicle can safely pass through the road section where the obstacle exists.
Wherein, deltaH is determined by H1 and H, and DeltaH is a negative value when H1 is less than or equal to H, and the passing requirement of the vehicle can be met without adjusting the height of the vehicle body. When H1> H, ΔH is positive, the vehicle body needs to be adjusted upwards by the damper to meet the passing demand of the vehicle.
The vehicle body adjustment height Δh is a difference between the height H1 of the road surface obstacle and the current height H of the vehicle body. In practical application, the actual adjusting height of the vehicle body can be delta H+H2, H2 is a reserved height value (such as 20mm, 30mm and the like), so that a certain gap can be reserved between the vehicle body and an obstacle after the height of the vehicle body is adjusted, and the trafficability of the vehicle is further improved.
In some embodiments of the invention, the controller is further configured to acquire a sprung mass variation of the air spring when the vehicle body adjustment height is less than or equal to zero, and adjust a stiffness of the air spring according to the sprung mass variation to promote driving comfort of the vehicle.
When delta H is less than or equal to 0, the shock absorber and the air spring do not exert lifting functions, the air spring can actively adjust the rigidity of the air spring according to the variation of the mass on the queen, so that the frequency deviation of the whole vehicle is unchanged, the smoothness and the comfortableness of the running of the vehicle are maintained, and the riding experience of drivers and passengers is improved.
It will further be appreciated that when ΔH is less than or equal to 0, the vehicle body height does not need to be adjusted upwardly, and the vehicle passing demand can also be satisfied, i.e., the vehicle body height does not need to be adjusted by a damper or an air spring. Therefore, the damping of the shock absorber can be further adjusted according to the driving mode of the vehicle, so that the driving comfort of the vehicle is improved.
In a further embodiment of the present invention, as shown in fig. 6, the controller is further configured to acquire the sprung mass variation of the air spring and acquire the driving mode of the vehicle when the vehicle body adjustment height is less than or equal to zero, adjust the stiffness of the air spring according to the sprung mass variation, and adjust the damping of the shock absorber according to the driving mode.
The driving mode of the vehicle comprises a first driving mode and a second driving mode, and the damping of the shock absorber is adjusted according to the driving mode of the vehicle, wherein when the driving mode of the vehicle is the first driving mode, the damping of the shock absorber is adjusted according to a first damping force curve; when the driving mode of the vehicle is the second driving mode, the damping of the shock absorber is adjusted according to the second damping force curve.
Referring to fig. 6, the first driving mode is different from the second driving mode, and accordingly, the damping change rates of the first damping force curve and the second damping force curve are different.
Wherein the first damping force curve and the second damping force curve are both graphs of the damping force F in relation to the travel speed V.
Referring to fig. 6, in both the first damping force curve and the second damping force curve, the damping of the shock absorber gradually increases with the running speed of the vehicle. The damping force of the shock absorber is adjusted according to a first damping force curve when the vehicle is in a first driving mode, and the damping force of the shock absorber is adjusted according to a second damping force curve when the vehicle is in a second driving mode. The first driving mode may be a sport driving mode, the second driving mode may be a comfortable driving mode, and of course, the driving mode of the vehicle is not limited to the first driving mode and the second driving mode, and may include a third driving mode, a fourth driving mode, and the like, and accordingly, the damping of the shock absorber may be adjusted according to an F-V damping curve corresponding to the driving mode.
In some embodiments of the invention, controlling at least one of the damper and the air spring according to the body adjustment height includes obtaining a highest height of the body, determining an adjustable height of the body according to the highest height of the body and a current height of the body, and controlling the damper and the air spring to lift the body when the body adjustment height is greater than zero and less than or equal to the adjustable height (i.e., L) of the body.
The "highest height of the vehicle body" refers to the maximum ground clearance that the vehicle body can be adjusted to by a damper or an air spring. Meanwhile, the adjustable height of the vehicle body is further determined according to the highest height of the vehicle body and the current height of the vehicle body, and the 'adjustable height' is a height value of the vehicle body which can be adjusted upwards through the lifting action of the shock absorber.
Further, when the height of the vehicle body is 0< [ delta ] H is less than or equal to L, the damper or the air spring can be controlled to lift the vehicle body according to the height of the vehicle body, and the height of the vehicle body can be adjusted to the target height so as to improve the trafficability of the vehicle.
Specifically, in the adjusting process, the height of the vehicle body can be adjusted through the cooperation of the shock absorber and the air spring, for example, the vehicle body is quickly lifted through the shock absorber, then the air spring is controlled to lift when the shock absorber keeps the lifted state of the vehicle body, so that the vehicle body with the adjusted height is supported through the air spring, after that, the shock absorber can cancel the lifting action, and the vehicle body height of the vehicle is only kept through the air spring.
Further, the adjustable height of the vehicle body is determined according to the following formula, l=hmax-h. Wherein L is the adjustable height of the car body, and Hmax is the highest height of the car body.
It should be noted that Hmax is a preset value, h is the obtained current height of the vehicle body, and the adjustable height L of the vehicle body can be further obtained based on the highest height Hmax of the vehicle body and the current height h of the vehicle body. The h can be a parameter acquired in real time, namely, the current height of the vehicle body after the shock absorber is controlled to adjust the height of the vehicle body once or a plurality of times.
In a further embodiment of the invention, controlling the damper and the air spring to lift the vehicle body comprises controlling the damper to generate thrust to lift the vehicle body to a preset height, controlling the electromagnetic valve of the air spring to fix the current height of the vehicle body to the preset height, and controlling the damper to stop working.
Wherein, the "preset height" refers to the height of the vehicle body that can smoothly pass through the obstacle.
Compared with an air spring, the shock absorber has high response speed, and the vehicle body can be lifted to a preset height in a shorter time, so that the requirement of quickly adjusting the height of the vehicle body is met, and the trafficability of the vehicle is improved in a short time. Meanwhile, the air spring is controlled to perform lifting action, so that the vehicle body is fixed at a preset height through the air spring.
It will be appreciated that the control of the air spring action may be performed simultaneously with the control of the shock absorber lifting action, or after the shock absorber lifting action is completed. The shock absorber is constructed as a linear motor shock absorber, and continuous power consumption is required in the process of lifting the vehicle body through the shock absorber, so that after the vehicle body is lifted through the shock absorber, the height of the vehicle body can be fixed by controlling the air spring to lift, the shock absorber can stop working (no power consumption), the energy consumed for keeping the height of the vehicle body is saved, and the shock absorber is suitable for a mode of real-time transient lifting adjustment of the vehicle.
In some embodiments of the invention, controlling at least one of the damper and the air spring according to the body adjustment height includes obtaining a highest height of the body, determining an adjustable height of the body according to the highest height of the body and a current height of the body, and controlling the damper to generate thrust to lift the vehicle when the body adjustment height is greater than the adjustable height of the body.
The "highest height of the vehicle body" refers to the maximum ground clearance that the vehicle body can be adjusted by a damper or an air spring. Meanwhile, the adjustable height of the vehicle body is further determined according to the highest height of the vehicle body and the current height of the vehicle body, and the 'adjustable height' is a height value of the vehicle body which can be adjusted upwards through the lifting action of the shock absorber.
Further, when the height of the automobile body is 0< [ delta ] H is smaller than or equal to L, the damper can be controlled to lift the automobile body according to the height of the automobile body, so that the height of the automobile body is adjusted, and the trafficability of the automobile is improved.
In some embodiments of the present invention, the adjustable height of the vehicle body is determined according to the following formula l=hmax-h. Wherein L is the adjustable height of the car body, and Hmax is the highest height of the car body.
It should be noted that Hmax is a preset value, h is the obtained current height of the vehicle body, and the adjustable height L of the vehicle body can be further obtained based on the highest height Hmax of the vehicle body and the current height h of the vehicle body. The h can be a parameter acquired in real time, namely, the current height of the vehicle body after the shock absorber is controlled to adjust the height of the vehicle body once or a plurality of times.
It can be understood that when the height Δh > L of the vehicle body is adjusted, the vehicle body is lifted only by controlling the damper or the air spring, and the vehicle still has road conditions of scraping and bumping due to the obstacle, so that the damper is controlled to generate thrust to enable the vehicle to jump, thereby adjusting the vehicle body to a higher off-position than the lifting mode, and meeting the requirement of passing the obstacle.
In some embodiments of the invention, controlling at least one of the damper and the air spring according to the body adjustment height includes obtaining a highest height of the body, determining an adjustable height of the body according to the highest height of the body and a current height of the body, and controlling the damper and the air spring to generate thrust to cause the vehicle to jump when the body adjustment height is greater than the adjustable height of the body.
In a further embodiment of the invention, controlling the shock absorber and the air spring to generate thrust to cause the vehicle to bounce includes controlling the shock absorber to store energy according to a first current while controlling the solenoid valve of the air spring to place the air spring in a pre-stressed state, and controlling the shock absorber according to a second current to cause the shock absorber and the air spring to generate thrust to cause the vehicle to bounce, the direction of the first current being opposite to the direction of the second current.
When the damper is controlled according to the first current, the damper may generate a downward pulling force while the air spring is in a pre-stressed state by controlling the solenoid valve. After the action, the shock absorber is controlled according to the second current, the shock absorber can instantaneously generate the maximum thrust to the vehicle body, meanwhile, the air spring also has upward thrust to the vehicle body, the vehicle body is driven to do acceleration motion upwards under the superposition of the two thrust, until the wheels in the unsprung mass are separated from the ground, and the whole system of the sprung mass and the unsprung mass takes the speed V as the initial speed to do uniform deceleration motion with the acceleration as g until the replaced mass and the unsprung mass drop to the ground of the wheels.
In some embodiments of the invention, the controller is further configured to output current to the linear motor to provide a pulling force to a wheel end of the vehicle to increase a distance between a wheel of the vehicle and the ground after the vehicle is tripped.
Referring to fig. 4, when the shock absorber is not controlled by the current after the vehicle is lifted, the ground clearance of the wheel is h1, and when the shock absorber is controlled by the output current, the ground clearance of the wheel is further increased, and h2 can be reached.
Specifically, after the vehicle takes off (namely the wheels are lifted off), the shock absorber can be further controlled through the first current, and at the moment, the shock absorber can drive the unsprung mass to approach one side of the vehicle body, so that the wheels can be lifted to a higher position, the ground clearance of the wheels is further improved, and the obstacle crossing capacity of the vehicle is improved.
The damper is constructed as a linear motor damper and comprises a stator and a rotor, wherein the stator and the rotor can relatively move along the linear direction.
The suspension assembly control damper function to achieve the take-off action according to the embodiment of the present invention will be described with reference to fig. 4:
when the suspension assembly is in the state 1, the suspension assembly is in a normal running or parking state;
When the suspension assembly is in a state 2, controlling the shock absorber according to the first current, enabling the stator and the rotor to move in opposite directions, and enabling the air spring to be in a pre-pressing state at the moment;
when the suspension assembly is in state 3, the damper is controlled according to the second current, the stator and the rotor do opposite movements, the damper applies upward thrust to the sprung mass, and the air spring releases energy;
when the suspension assembly is in state 4, the vehicle jumps;
when the suspension assembly is in the state 5, the output current controls the shock absorber, the stator and the rotor move in opposite directions, the unsprung mass is further driven to move upwards, and the ground clearance of the wheel is increased.
The vehicle provided by the embodiment of the invention comprises the control system of the suspension assembly, and can lift the vehicle body to adjust the height of the vehicle body, and can generate upward thrust after energy storage so as to enable the vehicle to jump, thereby fully improving the obstacle crossing capability of the vehicle. Meanwhile, the damping of the shock absorber can be adjusted according to the driving mode of the vehicle, so that the comfort and the control performance in the driving process of the vehicle are improved.
In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.
In the description of the invention, a "first feature" or "second feature" may include one or more of such features.
In the description of the invention, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature.
In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents.