CN112498361A

CN112498361A - Vehicle suspension self-checking system and self-checking method

Info

Publication number: CN112498361A
Application number: CN202011219060.4A
Authority: CN
Inventors: 张步云; 邹康; 戴涛; 李江; 张勇
Original assignee: Jiangsu University
Current assignee: Jiangsu University
Priority date: 2020-11-04
Filing date: 2020-11-04
Publication date: 2021-03-16
Anticipated expiration: 2040-11-04
Also published as: CN112498361B

Abstract

The invention provides a vehicle suspension self-checking system and a self-checking method, wherein the self-checking system comprises a plurality of acceleration sensors, a plurality of sensors and a plurality of sensors, wherein the acceleration sensors are used for acquiring longitudinal, transverse and axial acceleration signals of four unsprung masses of a vehicle in a moving process and longitudinal, transverse and axial acceleration signals of four sprung masses of the vehicle in the moving process; the displacement sensors are used for acquiring the relative motion conditions of wheels and a vehicle body of the vehicle in the static or moving process; the system comprises a plurality of road spectrum scanning systems, a plurality of road spectrum scanning systems and a plurality of road spectrum scanning systems, wherein the road spectrum scanning systems are used for collecting road information about the driving of wheels of a vehicle in the moving process and road information already driven; an ECU control unit; the ECU judges whether the suspension is in a normal state or not according to signals transmitted by the acceleration sensor, the displacement sensor and the road spectrum scanning system; the invention can monitor whether the damping efficiency of the vehicle four-wheel suspension system is normal or not in real time during the running process of the vehicle.

Description

Vehicle suspension self-checking system and self-checking method

Technical Field

The invention relates to the field of vehicles, in particular to a vehicle suspension self-checking system and a vehicle suspension self-checking method.

Background

The vehicle suspension is used as a force transmission part for connecting a vehicle body and wheels, transmits force and torque acting between the wheels and a vehicle frame, is an important part for ensuring the operating performance and the running safety of the vehicle, is used as a vibration isolation system between the vehicle body and the wheels, can effectively attenuate impact force transmitted to the vehicle frame or the vehicle body from an uneven road surface, and is also an important part for ensuring the riding comfort. Therefore, if the driver can timely know the working state of the vehicle suspension, the problem suspension can be found and replaced, and the smoothness and the safety of the vehicle during running can be guaranteed.

At present, the replacement time of the suspension system is not clearly specified, and the main judgment basis is instruction guidance on a vehicle maintenance manual, namely, the replacement of the suspension system is carried out after the vehicle reaches a certain driving mileage or driving age. However, even in the same type of vehicle, the wear degree of the suspension system is different within a certain driving distance or a certain driving year due to different driving habits and driving roads of the driver. On the one hand, suspension systems with large abrasion are not replaced in time, smoothness and safety of a vehicle during running can not be guaranteed, and on the other hand, suspension systems with small abrasion are replaced too early, so that resource waste can be caused.

In addition, when the vehicle runs on a poor road surface for a long time, the suspension system can be in continuous high-load work, the temperature of a spring and damping of the suspension system is continuously increased, if a driver of the vehicle cannot find the problem of the suspension in time, and measures are taken to cool the suspension system, the damping effect of the suspension is obviously reduced, so that the riding comfort is poor, and even the running safety of the vehicle is endangered.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a vehicle suspension self-checking system, which is used for monitoring whether the damping efficiency of four suspension systems is normal or not in real time after a vehicle moves.

The present invention achieves the above-described object by the following technical means.

A vehicle suspension self-test system, the vehicle comprising four suspension systems, the suspension systems being comprised of springs and damping, the self-test system comprising:

a plurality of acceleration sensors for obtaining longitudinal, lateral and axial acceleration signals of the four unsprung masses of the vehicle during movement and longitudinal, lateral and axial acceleration signals of the four sprung masses of the vehicle during movement;

the displacement sensors are used for acquiring the relative motion conditions of wheels and a vehicle body of the vehicle in the static or moving process;

the system comprises a plurality of road spectrum scanning systems, a plurality of road spectrum scanning systems and a plurality of road spectrum scanning systems, wherein the road spectrum scanning systems comprise a first road spectrum scanning system and a second road spectrum scanning system, the first road spectrum scanning system is used for collecting road information about driving of front left wheels and right wheels in the moving process of a vehicle, and the second road spectrum scanning system is used for collecting road information about driving of the left wheels and the right wheels;

the ECU control unit is used for acquiring vehicle parameters in the process of vehicle static or motion;

the acceleration sensor, the displacement sensor and the road spectrum scanning system are all connected with the ECU control unit, and the ECU control unit judges whether the suspension is in a normal state or not according to signals transmitted by the acceleration sensor, the displacement sensor and the road spectrum scanning system.

Preferably, the number of the acceleration sensors is eight, and the acceleration sensors are respectively mounted on four wheels and four suspensions of the vehicle.

Preferably, the number of the displacement sensors is four, and the displacement sensors are all arranged between the vehicle body and the chassis and are respectively close to four wheels of the vehicle.

Preferably, the road spectrum scanning systems are laser scanning systems, and the number of the road spectrum scanning systems is four, and the road spectrum scanning systems are respectively installed in the front of the left front wheel and the right front wheel and in the rear of the left rear wheel and the right rear wheel.

Preferably, the suspension system further comprises an instrument panel, and the instrument panel is connected with the ECU and used for displaying the real-time self-checking result of the suspension system.

The invention also provides a self-checking method of the vehicle suspension self-checking system, which comprises the following steps:

the method comprises the following steps: when the vehicle is started but does not move, the ECU acquires static information of the vehicle according to the displacement sensor;

step two: when a vehicle starts to move, an ECU control unit acquires the real-time vehicle running speed, acquires the vehicle body posture in the vehicle running state through a displacement sensor, calculates the theoretical power spectral density by combining signals transmitted by the first road spectrum scanning system and the second road spectrum scanning system, and calculates the actual power spectral density of the vehicle body response of the four suspension systems according to the signals transmitted by the acceleration sensor;

step three: the ECU performs signal analysis according to the four unsprung mass vibration acceleration time domain signals, further determines that the rigidity and the damping of the tire are in normal work, and performs signal processing on the four sprung mass vibration acceleration time domain signals to obtain the actual power spectral densities of the four suspension systems;

step four: and the ECU judges whether the theoretical power spectral density and the actual power spectral density of the suspension system are consistent or not, if so, the damping efficiency of the suspension system is judged to be normal, and if not, the damping efficiency of the suspension system is judged to be failed.

Preferably, the second step specifically includes:

when the vehicle starts to move, the ECU loads the real-time vehicle running speed;

the ECU control unit acquires the posture of a vehicle body in the running state of the vehicle through a displacement sensor, wherein the posture comprises a vehicle pitch angle and a vehicle roll angle, the time domain road surface unevenness of a road surface which is about to be driven by a left front wheel and a right front wheel is acquired through a first road spectrum scanning system, and the time domain road surface unevenness of the road surface which is about to be driven by the left front wheel and the right front wheel is calculated according to the distance from the first road spectrum scanning system of the road spectrum to a front shaft by combining the running speed of the vehicle;

the ECU calculates a time domain road spectrum of the right rear wheel and the left rear wheel by the front wheel road spectrum according to the time lag reason by combining the wheel track between the front axle and the rear axle of the vehicle and the running speed of the vehicle;

the method comprises the following steps that an ECU (electronic control unit) calculates sprung mass vibration acceleration theoretical power spectral density of four suspension systems of a vehicle for the first time according to time domain road surface input of four wheels, vehicle parameters and a whole vehicle dynamic model;

the ECU acquires time domain road surface unevenness of a road surface which is driven by the left rear wheel and the right rear wheel through the second road spectrum scanning system, and calculates the theoretical power spectral density of the vehicle body response time frequency domain of the four suspension systems for the second time by combining the rigidity damping parameters of the two suspension systems close to the rear axle, the distance from the rear axle to the second road spectrum acquisition system, the distance from the front axle to the rear axle, the vehicle static data and the vehicle dynamic data;

and the ECU judges whether the theoretical power spectral densities of the four suspension systems are effective or not, if so, the first theoretical power spectral density or the second theoretical power spectral density is loaded into the ECU, and if not, the vehicle driving dynamic information is acquired again to calculate the theoretical power spectral densities.

Preferably, the specific method for judging whether the theoretical power spectral densities of the four suspension systems are effective is as follows:

if the error between the theoretical power spectral density calculated for the first time and the theoretical power spectral density calculated for the second time of the suspension system is within 10%, the theoretical power spectral density of the suspension system is effective, and otherwise, the theoretical power spectral density of the suspension system is ineffective.

Preferably, the static information of the vehicle in the first step includes a vehicle mass, a vehicle body pitch angle and a vehicle body roll angle.

The invention has the beneficial effects that:

the invention is provided with a plurality of acceleration sensors, displacement sensors, a road spectrum scanning system and an ECU control unit, wherein the ECU control unit calculates and compares signals according to the sensors and the road spectrum scanning system so as to monitor whether the damping efficiency of the four-wheel suspension system of the vehicle is normal or not in real time in the driving process of the vehicle, and a driver can know the working state of the vehicle suspension in time, so that the driver can find and process the problem suspension in time, and the smoothness and the safety of the vehicle in the driving process can be ensured.

Drawings

FIG. 1 is a schematic diagram of a vehicle suspension self-test system according to an embodiment of the present invention;

fig. 2 is a flow chart of a self-checking method of the vehicle suspension self-checking system according to the embodiment of the invention.

Reference numerals:

1. 2, 3, 4 suspension systems; 5-front axle; 6-right front wheel; 7-left front wheel; 8-rear axle; 9-the right rear wheel; 10-left rear wheel; 11-a vehicle body; 12-a chassis; 13. 14, 15, 16, 17, 18, 19, 20-acceleration sensors; (ii) a 21-a front frame; 22. 23, 25, 26-road spectrum scanning system; 24-a rear frame; (ii) a 27. 28, 29, 30-displacement sensors; 31-an ECU control unit; 32-instrument panel.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "axial," "radial," "vertical," "horizontal," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for convenience in describing the invention and for simplicity in description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered as limiting. Furthermore, the terms "first", "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to specific situations.

A vehicle suspension self-checking system according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

Referring to fig. 1, the vehicle includes

suspension systems

1, 2, 3, 4, the

suspension systems

1, 2, 3, 4 are all composed of springs and dampers, wherein the lower mounting points of the suspension system 1 and the suspension system 2 are located near the left and right sides of a front axle 5 and near a right front wheel 6 and a left front wheel 7 respectively, the lower mounting points of the suspension system 3 and the suspension system 4 are located near the left and right sides of a rear axle 8 and near a right rear wheel 9 and a left rear wheel 10 respectively, the upper mounting points of the

suspension systems

1, 2, 3, 4 are all connected with a vehicle body 11, and the front axle 5 and the rear axle 8 are all mounted on a chassis 12.

The vehicle suspension self-checking system comprises a plurality of acceleration sensors, a plurality of displacement sensors, a plurality of road spectrum scanning systems and an ECU (electronic control Unit).

Specifically, the ECU control unit 31 is mounted on the vehicle body 11 for acquiring vehicle parameters including, but not limited to, running speed and tire pressure during the vehicle is stationary or moving, and the acceleration sensor, the displacement sensor and the road spectrum scanning system are all connected with the ECU control unit 31; an instrument panel 32 is located on the vehicle body 11 for displaying the real-time self-checking result of the suspension system.

The acceleration sensor in the embodiment is a three-way acceleration sensor, an acceleration sensor 13 is arranged at the axle center of the right front wheel 6, an acceleration sensor 14 is arranged at the axle center of the left front wheel 7, an acceleration sensor 15 is arranged at the axle center of the right rear wheel 9, an acceleration sensor 16 is arranged at the axle center of the left rear wheel 10, and the

acceleration sensors

13, 14, 15 and 16 are used for obtaining longitudinal, transverse and axial acceleration signals of unsprung mass in the moving process of the vehicle;

acceleration sensors

17, 18, 19, 20 are mounted at mounting points on the

suspension systems

1, 2, 3, 4, respectively, for acquiring longitudinal, lateral and axial acceleration signals of the sprung mass during vehicle motion.

The number of the road spectrum scanning systems is four, and the road spectrum scanning systems include a first road spectrum scanning system and a second road spectrum scanning system. The front part of the system chassis 12 is connected with a front frame 21, and the first road spectrum scanning system comprises road spectrum scanning systems 22 and 23 which are arranged on the front frame 21 and are respectively positioned right in front of the right front wheel 6 and the left front wheel 7 and are respectively used for collecting time domain road surface unevenness of the right front wheel 6 and the left front wheel 7 about to enter a road surface.

The rear part of the chassis 12 is connected with a rear frame 24, and the second road spectrum scanning system comprises road spectrum acquisition systems 25 and 26 which are arranged on the rear frame 24 and respectively positioned right behind the right rear wheel 9 and the left rear wheel 10 and used for collecting road information which is driven by four wheels of a vehicle in the moving process, including but not limited to road surface time domain unevenness.

The number of the displacement sensors is four, the

displacement sensors

27, 28, 29 and 30 are all installed between the vehicle body and the chassis and respectively close to the right front wheel 6, the left front wheel 7, the right rear wheel 9 and the left rear wheel 10 and are used for acquiring the relative motion conditions of the four wheels and the vehicle body in the static or moving process of the vehicle, and the ECU control unit 31 obtains the pitch angle and the roll angle of the vehicle body in the static state of the vehicle according to the ground clearance of the installation points of the four displacement sensors; and the ECU control unit 31 obtains the suspension spring compression amount and the spring stiffness coefficient, and obtains the static pressure of the vehicle body to the suspension system by using the elastic force formula, that is, the elastic force is equal to the spring stiffness coefficient multiplied by the spring compression amount, and the static pressure is the vehicle body mass, so that the vehicle parameters and the vehicle body posture obtained by the ECU control unit 31 include, but are not limited to, the vehicle mass, the vehicle body pitch angle and the vehicle body roll angle.

The following will further explain the implementation of the present invention with reference to fig. 1 and 2.

The method comprises the following steps: after the vehicle is powered on, the

displacement sensors

27, 28, 29 and 30 work for the first time to obtain the displacement between the four wheels and the vehicle body 11 under the static condition of the vehicle, the ECU control unit 31 obtains the static parameters of the vehicle and the attitude of the vehicle body including but not limited to the mass of the vehicle, the pitch angle and the roll angle of the vehicle body according to the signals of the four displacement sensors, and the obtained static data is put into the ECU 31 for storage;

step two: when the vehicle starts to move, the ECU control unit 31 acquires the real-time vehicle running speed, acquires the vehicle body posture in the vehicle running state through the

displacement sensors

27, 28, 29, 30, and calculates the theoretical power spectral density by combining the signals transmitted by the first road spectrum scanning system and the second road spectrum scanning system, and meanwhile, the ECU control unit 31 calculates the actual power spectral densities of the four suspension system vehicle body responses according to the signals transmitted by the

acceleration sensors

13, 14, 15, 16, specifically including:

s1, when the vehicle starts to move, the ECU 31 loads the distance between the front axle 5 and the rear axle 8 of the vehicle to obtain the real-time running speed of the vehicle;

s2, the ECU 31 acquires the vehicle body posture including the vehicle pitch angle and the vehicle roll angle in the vehicle driving state through the

displacement sensors

27, 28, 29 and 30, acquires the time domain road surface unevenness of the road surface which is about to be driven by the left front wheel 7 and the right front wheel 6 through the first road spectrum scanning system, and the ECU 31 calculates the time domain road spectrum which is driven by the left front wheel 7 and the right front wheel 6 and includes but is not limited to the time domain road surface unevenness according to the distance from the road spectrum collecting systems 22 and 23 to the front axle 5 and the vehicle driving speed. The ECU control unit 31 calculates time domain road spectrums driven by the right rear wheel 9 and the left rear wheel 10 according to the time lag principle by combining the wheel track between the front axle 5 and the rear axle 8 of the vehicle and the running speed of the vehicle, and the ECU control unit 31 calculates sprung mass vibration acceleration theoretical power spectral densities of four

suspension systems

1, 2, 3 and 4 of the vehicle for the first time according to four-wheel time domain road surface input, vehicle parameters and a whole vehicle dynamic model including but not limited to a seven-degree-of-freedom whole vehicle model, so that real-time vehicle body response frequency domain theoretical power spectral densities of the four suspension systems are obtained;

s3, the ECU 31 acquires road information that the right rear wheel 9 and the left rear wheel 10 have run through the second road spectrum scanning system, and calculates the theoretical power spectral density of the vehicle body response time-frequency domain of the four suspension systems for the second time by combining the rigidity damping parameters of the

suspension systems

3 and 4, the distance between the rear axle 8 and the road spectrum acquisition systems 25 and 26, the distance between the front axle 5 and the rear axle 8, the vehicle static data and the vehicle dynamic data;

and S4, the ECU 31 judges whether the theoretical power spectral densities of the four suspension systems are effective, if so, loads the first time or the second time of theoretical power spectral densities into the ECU, and if not, reacquires the vehicle running dynamic information to calculate the theoretical power spectral densities.

Preferably, the specific method for determining whether the theoretical power spectral densities of the four suspension systems are effective is as follows:

if the error between the theoretical power spectral density calculated for the first time and the theoretical power spectral density calculated for the second time of the suspension system is within 10%, the theoretical power spectral density of the suspension system is valid, and otherwise, the theoretical power spectral density of the suspension system is invalid.

Step three: the ECU 31 performs signal analysis according to the four unsprung mass vibration acceleration time domain signals, further determines that the rigidity and the damping of the tire are in normal work, and performs signal processing on the four sprung mass vibration acceleration time domain signals to obtain the actual power spectral densities of the four suspension systems;

step four: the ECU control unit 31 determines whether the theoretical power spectral density and the actual power spectral density of the suspension system are consistent, that is, determines that the error between the theoretical power spectral density and the actual power spectral density calculated for the first time by the suspension system is within 10%, if so, determines that the damping efficiency of the suspension system is normal, otherwise, determines that the damping efficiency of the suspension system is failed, and displays that a certain suspension system is not working normally on the instrument panel 32.

The vehicle suspension self-checking system and the method can lead a vehicle driver to know the working condition of the vehicle suspension system in time, prompt the vehicle owner to process the suspension system which does not work normally in time, and prevent the vehicle suspension system from being in an abnormal working state, thereby influencing riding comfort and driving safety.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean 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, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. 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 above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made in the above embodiments by those of ordinary skill in the art without departing from the principle and spirit of the present invention.

Claims

1. A vehicle suspension self-checking system, the vehicle includes four suspension systems, and suspension system comprises spring and damping, its characterized in that, the self-checking system includes:

the system comprises a plurality of road spectrum scanning systems, a plurality of road spectrum scanning systems and a plurality of road spectrum scanning systems, wherein the road spectrum scanning systems comprise a first road spectrum scanning system and a second road spectrum scanning system, the first road spectrum scanning system is used for collecting road information about driving of front left wheels and right wheels in the moving process of a vehicle, and the second road spectrum scanning system is used for collecting road information about driving of rear left wheels and right wheels;

2. The vehicle suspension self-checking system according to claim 1, wherein the number of the acceleration sensors is eight, and the acceleration sensors are respectively mounted on four wheels and four suspensions of the vehicle.

3. The vehicle suspension self-checking system according to claim 1, wherein the number of the displacement sensors is four, and the displacement sensors are respectively installed between the vehicle body and the chassis and respectively close to four wheels of the vehicle.

4. The vehicle suspension self-checking system according to claim 3, wherein the road spectrum scanning systems are laser scanning systems, and the number of the road spectrum scanning systems is four, and the road spectrum scanning systems are respectively installed right in front of the left front wheel and the right front wheel and right in back of the left rear wheel and the right rear wheel.

5. The vehicle suspension self-checking system according to claim 1, further comprising an instrument panel connected to the ECU for displaying real-time suspension system self-checking results.

6. A self-checking method of a vehicle suspension self-checking system according to claim 2, comprising:

7. The self-test method of the vehicle suspension self-test system according to claim 6, wherein the second step specifically comprises:

the ECU acquires the posture of a vehicle body in the running state of the vehicle through a displacement sensor, wherein the posture comprises a vehicle pitch angle and a vehicle roll angle, the time domain road surface unevenness of the road surface which is about to be driven by the left front wheel and the right front wheel is acquired through a first road spectrum scanning system, and the time domain road surface unevenness of the road surface which is driven by the left front wheel and the right front wheel is calculated by the ECU according to the distance from the first road spectrum scanning system of the road spectrum to a front shaft and by combining the running speed of the vehicle;

the method comprises the following steps that an ECU (electronic control unit) calculates sprung mass vibration acceleration theoretical power spectral densities of four suspension systems of a vehicle for the first time according to time domain road surface input of four wheels, vehicle parameters and a whole vehicle dynamic model;

the ECU acquires time domain road surface unevenness of a road surface which is driven by the left rear wheel and the right rear wheel through the second road spectrum scanning system, and calculates the theoretical power spectral density of the vehicle body response time-frequency domain of the four suspension systems for the second time by combining the rigidity damping parameters of the two suspension systems close to the rear axle, the distance from the rear axle to the second road spectrum acquisition system, the distance from the front axle to the rear axle, the vehicle static data and the vehicle dynamic data;

and the ECU judges whether the theoretical power spectral densities of the four suspension systems are effective or not, if so, the first time theoretical power spectral density or the second time theoretical power spectral density is loaded into the ECU, and if not, the vehicle driving dynamic information is acquired again to calculate the theoretical power spectral densities.

8. The self-checking method of the vehicle suspension self-checking system according to claim 7, wherein the specific method for judging whether the theoretical power spectral densities of the four suspension systems are effective is as follows:

9. The self-checking method of the vehicle suspension self-checking system according to claim 6, wherein the vehicle static information in the first step comprises vehicle mass, vehicle pitch angle and vehicle roll angle.