Integrated electronic control type automobile chassis suspension control system

Abstract

The invention discloses an integrated electric control type automobile chassis suspension control system, relates to the technical field of chassis suspension control, and solves the technical problems of how to accurately sense a vehicle motion state and road surface information, accurately judge road conditions and accurately adjust parameters such as rigidity and damping of an automobile chassis suspension in real time based on the road conditions. According to the method, elevation data of measurement points are accurately obtained, calculation is performed by applying an international flatness index standard algorithm, flat and uneven road conditions are distinguished, motion equations are established for different road conditions, and the rigidity and damping are calculated and adjusted by combining actual vehicle parameters and road surface parameters; reference rigidity and damping are calculated according to vehicle dynamic characteristics and design parameters, and real-time parameters are adjusted; under the non-flat road condition, the suspension parameters can be dynamically adjusted according to the specific road condition characteristics no matter the continuous condition or the discontinuous condition, different driving working conditions can be better adapted, and the vehicle driving stability and the riding comfort are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of chassis suspension control, and particularly to an integrated electric control type automotive chassis suspension control system. Background Art

[0002] Electric control vehicles are also called new energy vehicles. With the rapid development of automotive technology, especially the rapid rise of electric vehicles, improving the driving experience of drivers has become a key concern for many automobile manufacturers.

[0003] According to the patent application with the publication number CN115742654A, a dual suspension control system based on an automotive chassis domain controller is disclosed, including an automotive chassis domain controller, a vehicle air suspension system, and a vehicle damping suspension system. The automotive chassis domain controller is used to control the actions of the vehicle air suspension system and the vehicle damping suspension system, and it further includes: a driver driving style analysis module and a road condition detection module. This dual suspension control system based on an automotive chassis domain controller is provided with a driver driving style analysis module and a road condition detection module. During driving, the automotive chassis domain controller can control and adjust the vehicle air suspension system and the vehicle damping suspension system in real time according to the driver's driving style and the actual road conditions, actively control the air suspension system and the adaptive damping suspension system, and adjust the damping and stiffness of the vehicle chassis in real time during vehicle driving, so as to improve the handling stability of vehicle driving, make the vehicle driving more stable, safe and reliable.

[0004] In terms of road condition judgment, the traditional system may lack precise measurement and analysis means and is difficult to accurately obtain key information such as road surface flatness. In terms of suspension parameter adjustment, it cannot be accurately and dynamically adjusted well according to real-time road conditions and vehicle states, resulting in difficulties in balancing the driving stability and comfort of the vehicle under different road conditions and being unable to fully meet the increasing demands of users for vehicle performance. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides an integrated electric control type automotive chassis suspension control system, which solves the problems of how to accurately sense the vehicle motion state and road surface information, accurately judge the road conditions, and based on this, adjust parameters such as the stiffness and damping of the automotive chassis suspension in real time and accurately.

[0006] To achieve the above objectives, the present invention is realized through the following technical solutions: An integrated electric control type automotive chassis suspension control system, including:

[0007] A road condition comprehensive judgment unit, which is used to analyze the road surface information transmitted by the sensor data acquisition unit, obtain the measurement points in the real-time section, calculate the flatness of the real-time section according to the measurement points, and compare with the preset index to generate flat road condition and uneven road condition information;

[0008] The flat road condition control analysis unit analyzes the acquired flat road condition information, establishes the motion equation of the vehicle, calculates the stiffness and damping of the vehicle corresponding to the flat road condition, and adjusts the real-time stiffness and damping of the vehicle based on this as a standard, generates suspension control information, and transmits it to the control information output unit;

[0009] The non-flat road condition control analysis unit analyzes the acquired non-flat road condition information, divides the real-time road section into equal parts to obtain equal parts road sections, calculates the average elevation of each part, and classifies them into continuous flat road conditions and discontinuous flat road conditions according to the average elevation;

[0010] Analyze the continuous flat road condition, calculate the elevation difference of the continuous flat road condition and record it as the standard difference, calculate the adjustment stiffness and adjustment damping based on this as a standard, and at the same time adjust the real-time stiffness and real-time damping, generate suspension control information, and similarly analyze the discontinuous flat road condition, generate suspension control information, and transmit it to the control information output unit.

[0011] As a further solution of the present invention, it further includes a sensor data acquisition unit and a control information output unit;

[0012] The sensor data acquisition unit is used to sense the motion state and road surface information of the vehicle in real time through sensors and transmit them to the road condition comprehensive judgment unit;

[0013] The control information output unit is used to transmit the acquired suspension control information to the execution structure.

[0014] As a further solution of the present invention, the specific manner in which the road condition comprehensive judgment unit generates flat road condition and non-flat road condition information is:

[0015] The sensor obtains the real-time road section length L of the vehicle and the elevation Zi of a corresponding plurality of measurement points i, where i = 1, 2,..., N, and N represents the number of measurement points. According to the formula Calculate the international roughness index IRI corresponding to the real-time road section;

[0016] Compare IRI with a preset index. If IRI is greater than the preset index, generate non-flat road condition information and transmit it to the non-flat road condition control analysis unit at the same time. On the contrary, if IRI is less than the preset index, generate flat road condition information and transmit it to the flat road condition control analysis unit at the same time.

[0017] As a further solution of the present invention, the specific manner in which the flat road condition control analysis unit analyzes the flat road condition information is:

[0018] Taking the vertical displacement z of the vehicle body mass center as the generalized coordinate, and establishing the motion equation

[0019] where m is the vehicle mass, c is the damping coefficient, k is the total stiffness of the air spring and the tire, and F is the vertical external force acting on the vehicle body, is the second derivative of the vertical displacement z of the vehicle body mass center with respect to time t, that is, the acceleration in the vertical direction of the vehicle body, is the first derivative of the vertical displacement z of the vehicle body mass center with respect to time t, that is, the velocity in the vertical direction of the vehicle body, and z refers to the vertical displacement of the vehicle body mass center.

[0020] As a further solution of the present invention, the specific manner in which the flat road condition control unit generates suspension control information is as follows:

[0021] Obtain the total mass corresponding to the vehicle and denote it as m total and the vertical displacement Δz max , and according to the formula calculate the corresponding stiffness k1, where g is the acceleration due to gravity, and then substitute the calculated stiffness k into the motion equation to calculate the damping c1;

[0022] At the same time, obtain the real-time stiffness and real-time damping of the vehicle, and adjust the real-time stiffness and real-time damping with the calculated stiffness k1 and damping c1 as the standards to generate suspension control information, and transmit it to the control information output unit.

[0023] As a further solution of the present invention, the specific manner in which the non-flat road condition control analysis unit analyzes the non-flat road condition information is as follows:

[0024] Uniformly segment the real-time road section, obtain the measurement points and their elevations of each equally divided section, calculate the average elevation of each equally divided section, and then calculate the difference between adjacent average elevations, and compare it with the preset difference set by the operator;

[0025] If the difference is greater than the preset value, the corresponding measurement point is not classified; if it is less, the measurement point is classified, the classified road section is marked as a continuous non-flat road condition, and the unclassified one is marked as a discontinuous non-flat road condition.

[0026] As a further solution of the present invention, the specific manner in which the non-flat road condition control analysis unit analyzes the continuous flat road condition is as follows:

[0027] Obtain the real-time stiffness and real-time damping of the vehicle, calculate the average elevation of the continuous flat road condition, and calculate the adjusted stiffness k0 and adjusted damping c0 based on this as the standard, and θ is the slope angle of the road surface, m is the total mass of the vehicle, g is the acceleration due to gravity, c0 = ωP + λR, where ω and λ are coefficients determined according to experimental data, P is the average slope of the road surface, and R is the average curvature of the road surface;

[0028] Compare the obtained adjustable stiffness and adjustable damping with the real-time stiffness and real-time damping, and adjust the latter based on the former as the standard to generate suspension control information.

[0029] As a further solution of the present invention, the calculation method of the average road surface curvature is as follows:

[0030] Obtain the three-dimensional coordinates (xi, yi, zi) corresponding to the measurement point i, and fit the three-dimensional curve equation z = f(x, y) of the road surface according to the measurement point coordinates;

[0031] Calculate the first-order partial derivative Calculate the second-order partial derivative

[0032] According to the curvature formula of the three-dimensional curve Calculate the curvature R of the measurement point i , and according to the summation formula Calculate the average curvature R.

[0033] The present invention provides an integrated electronically controlled automotive chassis suspension control system. Compared with the prior art, it has the following beneficial effects:

[0034] By using professional measurement equipment such as a laser profilometer, the present invention can more accurately judge the road surface flatness by accurately obtaining the elevation data of the measurement points and using the international roughness index standard algorithm. It can distinguish between flat and uneven road conditions. For uneven road conditions, it can further subdivide continuous and discontinuous uneven road conditions by calculating the elevation mean and difference in a uniform segmented manner for the road section. Compared with the prior art, the road condition judgment is more detailed and accurate.

[0035] For different road conditions, the present invention calculates the adjustable stiffness and damping based on the scientifically established motion equation, combined with the actual vehicle parameters and road surface parameters. Under flat road conditions, the reference stiffness and damping are calculated based on the vehicle dynamics characteristics and design parameters, and the real-time parameters are adjusted; under uneven road conditions, whether continuous or discontinuous, the suspension parameters can be dynamically adjusted according to the specific road condition characteristics, better adapting to different driving conditions and improving the vehicle driving stability and riding comfort. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a system principle block diagram of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0037] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0038] Embodiment 1

[0039] Please refer to Figure 1 , this application provides an integrated electronically controlled automotive chassis suspension control system, including a sensor data acquisition unit, a road condition comprehensive judgment unit, a flat road condition control analysis unit, a non-flat road condition control analysis unit, and a control information output unit, and in combination with Figure 1 it can be known that the above functional units are connected in a one-way electrical manner.

[0040] The sensor data acquisition unit is used to sense the motion state of the vehicle and road surface information in real time through sensors and transmit them to the road condition comprehensive judgment unit.

[0041] The comprehensive condition judgment unit is used to analyze the obtained road surface information, judge the road condition, generate flat road condition information or uneven road condition information, and the specific judgment method is as follows:

[0042] Using professional measuring equipment such as a laser profilometer, obtain the length of the real-time driving section of the vehicle, denoted as L. At the same time, determine multiple measurement points on this section, represented by i, and i = 1, 2,..., N, where N represents the number of measurement points. For each measurement point i, measure and record its corresponding elevation Zi. The elevation refers to the distance from this point along the plumb line direction to the geoid, and this distance is obtained through the high-precision elevation measurement module inside the measuring equipment;

[0043] For example, when the vehicle is driving on a 200-meter-long road, the laser profilometer automatically determines 100 measurement points (i.e., N = 100). At measurement point i = 1, the elevation Z1 = 10.23 meters is measured through the elevation measurement module; at i = 2, Z2 = 10.25 meters is measured, and so on, to complete the acquisition of elevation data for 100 measurement points.

[0044] Based on the collected elevation data of the measurement points, calculate using the standard algorithm of the international roughness index (IRI). The calculation formula of IRI is:

[0045]

[0046] (Among them, the integral operation is completed by the professional software built into the measuring device through discretization during actual calculation). Through this formula, the International Roughness Index (IRI) corresponding to the real-time driving section of the vehicle is obtained;

[0047] Continuing with the above example, the software built into the measuring device substitutes the elevation data of these 100 measurement points into the formula for calculation. The software will divide the integral interval according to the measurement points according to the rules of discretization, and calculate each small segment in turn Combined with the road section length L = 200 meters, the International Roughness Index (IRI) of this road section is finally obtained. Assuming that after complex calculations, the calculation result IRI = 3.5;

[0048] Compare the calculated International Roughness Index (IRI) with the pre-set standard index. This pre-set index is comprehensively determined based on various factors such as the vehicle design performance, ride comfort requirements, and industry general standards. If the IRI is greater than the pre-set index, it indicates that the road condition of the real-time road section is uneven. The system will automatically generate uneven road condition information including details such as the road section location and unevenness degree, and transmit it to the non-flat road condition control and analysis unit for subsequent corresponding adjustments to systems such as the chassis suspension. On the contrary, if the IRI is less than the pre-set index, it means that the real-time road condition is flat. The system will generate flat road condition information including the road section location and other contents, and transmit it to the flat road condition control and analysis unit to maintain the normal driving state of the vehicle under good road conditions;

[0049] Assume that according to the vehicle design, the pre-set International Roughness Index is 2.0 m / km. Since the calculated IRI = 3.5 m / km is greater than the pre-set index of 2.0 m / km, the system determines that the road condition of this road section is uneven. At this time, the system automatically generates uneven road condition information. If the calculated IRI is less than 2.0 m / km, such as IRI = 1.5 m / km, the system will generate flat road condition information, record the road section location, etc., and transmit it to the flat road condition control and analysis unit.

[0050] Flat road condition control and analysis unit. This unit is used to analyze the obtained flat road condition information, obtain the suspension stiffness and damping parameters of the vehicle, and at the same time obtain the corresponding motion state and vehicle information of the vehicle. Then, according to the motion state, the suspension of the vehicle is controlled and adjusted, and the specific control and adjustment method is as follows:

[0051] When studying the dynamic characteristics of the vehicle suspension system, taking the vertical displacement z of the vehicle body center of mass as the generalized coordinate can effectively describe the motion state of the vehicle in the vertical direction. According to Newton's second law, the resultant external force acting on an object is equal to the product of its mass and acceleration. For the vehicle suspension system, the established motion equation is:

[0052]

[0053] The meanings of the parameters in the above formula are as follows:

[0054] m represents the vehicle mass, which encompasses the total mass of all loads on the vehicle, such as the body, passengers, and cargo, with the unit of kilogram (kg). It is a key parameter determining the vehicle's inertia.

[0055] c is the damping coefficient, with the unit of Newton-second per meter (N·s / m), reflecting the ability of damping components such as shock absorbers to impede the relative movement of the vehicle. The larger the damping coefficient, the stronger the attenuation effect on vibration.

[0056] k is the total stiffness of the air spring and the tire, with the unit of Newton per meter (N / m), indicating the ability of the suspension system to resist vertical deformation. The greater the stiffness, the smaller the body displacement under the action of the same external force.

[0057] F is the vertical external force acting on the vehicle body, with the unit of Newton (N), including the excitation force caused by road unevenness, the force generated by vehicle load changes, etc. These external forces will affect the vertical motion state of the vehicle.

[0058] is the second derivative of the vertical displacement z of the vehicle body's center of mass with respect to time t, that is, the vertical acceleration of the vehicle body, with the unit of meter per second squared (m / s 2 ), describing the rate of change of the vehicle body's vertical motion speed.

[0059] is the first derivative of the vertical displacement z of the vehicle body's center of mass with respect to time t, that is, the vertical speed of the vehicle body, with the unit of meter per second (m / s), reflecting the speed of the vehicle body's movement in the vertical direction.

[0060] z refers to the vertical displacement of the vehicle body's center of mass, with the unit of meter (m), intuitively reflecting the moving distance of the vehicle body in the vertical direction relative to the initial position.

[0061] Based on the above motion equation, the corresponding stiffness and damping coefficient of the vehicle can be further calculated, estimated according to the vehicle's design load capacity and the maximum allowable displacement of the vehicle body. Obtain the total mass when the vehicle is fully loaded, denoted as m total , and at the same time, clarify the maximum allowable vertical displacement Δz of the vehicle body when it is fully loaded max , considering the extreme situations that the vehicle may face in actual use, introduce a safety factor S, generally taking values according to engineering experience, for example, S = 1.2. According to the principle of mechanics, at this time, according to the formula calculate the stiffness k1, where g is the acceleration due to gravity, approximately taking the value of 9.8 m / s 2 ;

[0062] For example, the design full-load total mass m of a car totalis 2000 kg, and the maximum vertical displacement Δz allowed for the vehicle body when fully loaded max is 0.05 m, and the safety factor is 1.2. Then, according to the above formula, the calculated stiffness k1 is 470400 N / m;

[0063] After obtaining the stiffness k1, substitute it into the motion equation to calculate the damping coefficient c1. Assume that when the vehicle is driving on a flat road surface, through sensor measurement, m = 2000 kg, = 2 m / s 2 , z = 0.02 m, F = 10000 N. Substitute k1 = 470400 N / m into the above formula to calculate c1 = 2304 N·s / m;

[0064] During the vehicle driving process, the sensor will obtain the real-time stiffness k of the vehicle in real time real and the real-time damping c real . The system uses the calculated stiffness k1 and c1 as reference standards to adjust the real-time stiffness and real-time damping. For example, the real-time stiffness is k real = 450000 N / m, which is less than the calculated k1 = 470400 N / m. The system may control the air spring inflation and other methods to increase the stiffness. The real-time damping c real = 2000 N·s / m, which is less than c1 = 2304 N·s / m. The system may adjust the internal structure of the shock absorber (such as changing the size of the damping hole, etc.) to increase the damping. Through such an adjustment process, suspension control information including stiffness adjustment instructions, damping adjustment instructions, etc. is generated and transmitted to the control information output unit.

[0065] Embodiment 2

[0066] As Embodiment 2 of the present invention, it is implemented on the basis of Embodiment 1, and the differences from Embodiment 1 are as follows:

[0067] The non-flat road condition control analysis unit is used to analyze the obtained non-flat road condition information, obtain the real-time road section of the vehicle, and analyze and classify the non-flat situation of the real-time road section to obtain continuous non-flat road conditions and discontinuous non-flat road conditions. The specific classification processing method is as follows:

[0068] Perform uniform segmentation on the acquired real-time road section, dividing it into multiple equally divided road sections with equal lengths. Assume the length of the real-time road section is L, and divide it equally into m sections, with the length of each section l = L / m. For each equally divided road section, determine and obtain its corresponding measurement points. These measurement points should be evenly distributed on the road section. For example, set a measurement point at a certain interval. For each measurement point, use a high-precision measurement device (such as a laser profilometer) to obtain its corresponding elevation value;

[0069] For each equally divided road section, calculate the mean value of the elevations of all measurement points within this section. Let the j-th equally divided road section have nj measurement points, and their measurement point elevations be Z j1 ,Z j2 ,Z jn ,then the elevation mean value of this section is According to this method, calculate the elevation mean values of all m equally divided road sections in turn Then calculate the difference between adjacent elevation mean values where j = 1, 2, m - 1;

[0070] The operator will set a preset difference D according to actual needs and experience preset ,compare the calculated Dj with the preset difference D preset ,if Dj > D preset ,it indicates that the elevation change between these two adjacent equally divided road sections is relatively large, and the road surface conditions are significantly different. At this time, do not classify the measurement points corresponding to these two adjacent equally divided road sections. On the contrary, if Dj ≤ D preset ,it means that the elevation change between these two adjacent equally divided road sections is relatively stable, and the road surface conditions are relatively similar. The measurement points corresponding to them can be classified into one category;

[0071] By comparing and classifying the differences of all adjacent equally divided road sections one by one, the set of all classified equally divided road sections can be obtained. These classified road sections can be marked as continuous non-flat road conditions, that is, the road surface conditions of these road sections are relatively consistent and all in a non-flat state. For those equally divided road sections that are not classified, since their elevation changes with adjacent road sections exceed the preset range, it indicates that they show isolated non-flat states in the entire road section. Therefore, these road sections are marked as discontinuous non-flat road conditions.

[0072] Then perform adjustment analysis on the obtained continuous flat road conditions, obtain the real-time stiffness and real-time damping of the vehicle, establish the corresponding motion equation, calculate the average elevation corresponding to the continuous flat road conditions, and calculate the corresponding adjustment stiffness and adjustment damping with the average elevation as the standard. By establishing the motion equation and calculating the elevation difference between the current road condition and the continuous flat road condition, which is recorded as the standard difference, and substituting the obtained standard difference into the formula Calculate the corresponding adjustment stiffness \(k_0\), where \(\theta\) is the slope angle of the road surface, \(m\) is the total mass of the vehicle, and \(g\) is the acceleration due to gravity, approximately taken as \(9.8m / s\). 2 , \(mgsin\theta\) is the component of gravity along the vertical direction. At the same time, calculate the corresponding adjustment damping \(c_0\) according to the formula \(c_0 = \omega P+\lambda R\), where \(\omega\) and \(\lambda\) are coefficients determined according to experimental data, \(P\) is the average slope of the road surface, and \(R\) is the average curvature of the road surface;

[0073] The calculation method of the average curvature of the road surface is as follows:

[0074] Obtain all measurement points \(i\), and obtain the corresponding three-dimensional coordinates \((x_i,y_i,z_i)\) of the measurement point \(i\), where \(z_i\) represents the elevation of the measurement point, and \(x_i\) and \(y_i\) represent the horizontal position coordinates. Fit the three-dimensional curve equation \(z = f(x,y)\) of the road surface according to the coordinate data of the measurement points, and then take the partial derivatives of \(x\) and \(y\) respectively. Specifically, calculate the first-order partial derivative: Calculate the second-order partial derivative: Then according to the curvature calculation formula of the three-dimensional curve: Calculate the curvature \(R\) i , and at the same time according to the summation formula Calculate the average curvature \(R\);

[0075] Compare the obtained adjustment stiffness and adjustment damping with the real-time stiffness and real-time damping, and adjust the latter based on the former as the standard to generate suspension control information, and at the same time transmit it to the control information output unit;

[0076] Conduct adjustment analysis on the obtained discontinuous flat road conditions, in the same way as the analysis method of continuous flat road conditions, generate suspension control information, and transmit it to the control information output unit.

[0077] The control information output unit is used to transmit the obtained suspension control information to the corresponding actuator structure.

[0078] Embodiment III

[0079] As Embodiment III of the present invention, the key lies in combining the implementation processes of Embodiment I and Embodiment II.

[0080] Some of the data in the above formulas are only taken for numerical calculation without substituting parameter units for calculation. At the same time, the content not described in detail in this specification belongs to the prior art well-known to those skilled in the art.

[0081] The above embodiments are only used to illustrate the technical method of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical method of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical method of the present invention.

Claims

1. An integrated electronically controlled automotive chassis suspension control system, characterized in that, Including: A comprehensive road condition judgment unit, which is used to analyze the road surface information transmitted by the sensor data acquisition unit, obtain the measurement points in the real-time section, calculate the flatness of the real-time section based on the measurement points, and compare it with the preset index to generate flat road condition and uneven road condition information; A flat road condition control analysis unit, which analyzes the obtained flat road condition information, establishes the motion equation of the vehicle, calculates the stiffness and damping of the vehicle corresponding to the flat road condition, and adjusts the real-time stiffness and damping of the vehicle based on this as a standard, generates suspension control information, and transmits it to the control information output unit; A non-flat road condition control analysis unit, which analyzes the obtained non-flat road condition information, evenly divides the real-time section to obtain evenly divided sections, calculates the average elevation of each section, and classifies them according to the average elevation to obtain continuous flat road conditions and discontinuous flat road conditions; Analyze the continuous flat road condition, calculate the elevation difference of the continuous flat road condition and record it as the standard difference, and calculate the adjusted stiffness and adjusted damping based on this as a standard, and at the same time adjust the real-time stiffness and real-time damping to generate suspension control information. Similarly, analyze the discontinuous flat road condition to generate suspension control information and transmit it to the control information output unit.

2. An integrated electronically controlled automotive chassis suspension control system according to claim 1, characterized in that, It also includes a sensor data acquisition unit and a control information output unit; The sensor data acquisition unit is used to sense the motion state and road surface information of the vehicle in real time through sensors and transmit them to the comprehensive road condition judgment unit; The control information output unit is used to transmit the obtained suspension control information to the execution structure.

3. An integrated electronically controlled automotive chassis suspension control system according to claim 1, characterized in that, The specific method for the comprehensive road condition judgment unit to generate flat road condition and uneven road condition information is as follows: The sensor obtains the real-time road section length L of the vehicle and the elevations Zi of a plurality of corresponding measurement points i, where i = 1, 2, …, N, and N represents the number of measurement points. According to the formula the ride index IRI corresponding to the real-time road section is calculated. Compare the IRI with the preset index. If the IRI is greater than the preset index, generate uneven road condition information and transmit it to the non-flat road condition control analysis unit at the same time. On the contrary, if the IRI is less than the preset index, generate flat road condition information and transmit it to the flat road condition control analysis unit at the same time.

4. An integrated electronically controlled automotive chassis suspension control system according to claim 1, characterized in that, The specific method for the flat road condition control analysis unit to analyze the flat road condition information is as follows: Taking the vertical displacement \(z\) of the vehicle body's center of mass as the generalized coordinate, and establishing the motion equation where \(m\) is the vehicle mass, \(c\) is the damping coefficient, \(k\) is the total stiffness of the air spring and the tire, and \(F\) is the vertical external force acting on the vehicle body, is the second derivative of the vertical displacement \(z\) of the vehicle body's center of mass with respect to time \(t\), that is, the acceleration in the vertical direction of the vehicle body, is the first derivative of the vertical displacement \(z\) of the vehicle body's center of mass with respect to time \(t\), that is, the velocity in the vertical direction of the vehicle body, and \(z\) refers to the vertical displacement of the vehicle body's center of mass.

5. An integrated electronically controlled automotive chassis suspension control system according to claim 1, wherein The specific method for the flat road condition control unit to generate suspension control information is as follows: Obtain the total mass corresponding to the vehicle and denote it as m total and the vertical displacement Δz max , according to the formula calculate the corresponding stiffness k1, where g is the acceleration due to gravity, and then substitute the calculated stiffness k into the motion equation to calculate the damping c1; At the same time, obtain the real-time stiffness and real-time damping of the vehicle, and adjust the real-time stiffness and real-time damping based on the calculated stiffness k1 and damping c1 as a standard, generate suspension control information, and transmit it to the control information output unit.

6. An integrated electronically controlled automotive chassis suspension control system according to claim 1, characterized in that, The specific method for the non-flat road condition control analysis unit to analyze the uneven road condition information is as follows: Evenly segment the real-time section, obtain the measurement points and their elevations of each evenly divided section, calculate the average elevation of each evenly divided section, then calculate the difference between adjacent average elevations, and compare it with the preset difference set by the operator; If the difference is greater than the preset value, the corresponding measurement points are not classified; If it is less than, the measurement points are classified, the classified sections are marked as continuous non-flat road conditions, and the unclassified ones are marked as discontinuous non-flat road conditions.

7. An integrated electronically controlled automotive chassis suspension control system according to claim 1, characterized in that, The specific method for the non-flat road condition control analysis unit to analyze the continuous flat road condition is as follows: Obtain the vehicle's real-time stiffness and real-time damping, calculate the average elevation of the continuous flat road condition, and use this as a standard to calculate the adjusted stiffness k0 and adjusted damping c0. And θ is the slope angle of the road surface, m is the total mass of the vehicle, g is the acceleration due to gravity, c0 = ωP + λR, where ω and λ are coefficients determined according to experimental data, P is the average slope of the road surface, and R is the average curvature of the road surface; Compare the obtained adjusted stiffness and adjusted damping with the real-time stiffness and real-time damping, and adjust the latter based on the former as a standard to generate suspension control information.

8. An integrated electronically controlled automotive chassis suspension control system according to claim 7, characterized in that, The calculation method of the average curvature of the road surface is as follows: Obtain the three-dimensional coordinates (xi, yi, zi) corresponding to the measurement point i, and fit the three-dimensional curve equation z = f(x, y) of the road surface according to the measurement point coordinates; Calculate the first-order partial derivative Calculate the second-order partial derivative According to the curvature formula of the three-dimensional curve calculate the curvature R of the measurement point i , and according to the summation formula calculate the average curvature R obtained.

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