An adaptive active suspension system based on muddy roads

Abstract

This invention discloses an adaptive active suspension system based on muddy road surfaces, comprising a real-time vehicle information acquisition unit, an active suspension performance calculation unit, a muddy road surface condition recognition unit, and an active suspension parameter adjustment unit. The real-time vehicle information acquisition unit is used to collect vehicle parameters in real time during driving; the active suspension performance calculation unit is used to calculate the comprehensive performance index Q of the active suspension; the muddy road surface condition recognition unit is used to identify the muddy degree of the road surface currently being driven on; and the active suspension parameter adjustment unit is used to adjust the parameters of the active suspension according to the muddy degree of the road surface currently being driven on.

Description

Technical Field

[0001] This invention relates to an adaptive active suspension system for muddy road surfaces. Background Technology

[0002] When vehicles travel on muddy roads, the mud, being typically soft and sticky, causes mud to adhere to the tires. This reduces friction and traction between the tires and the road surface, making the vehicle prone to skidding and sideslipping. This not only affects ride comfort but also the safety of occupants. Adaptive active suspension systems for muddy roads reduce the likelihood of these problems by adjusting the stiffness, height, and damping of the active suspension on varying degrees of mud. However, current research primarily focuses on the adaptive capabilities of active suspensions on smooth roads, neglecting their adaptive and self-adjusting capabilities on muddy surfaces. Therefore, to address these issues, this invention proposes an adaptive active suspension system for muddy roads. Summary of the Invention

[0003] The purpose of this invention is to provide an adaptive active suspension system based on muddy road surfaces to solve the problems encountered in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: an adaptive active suspension system based on muddy road surfaces, comprising: a real-time vehicle information acquisition unit, an active suspension performance calculation unit, a muddy road surface status recognition unit, and an active suspension parameter adjustment unit;

[0005] The vehicle information real-time acquisition unit is used to collect vehicle parameters in real time during the driving process, including: vehicle speed v, and the compression and extension speed v of the shock absorber spring. d The number of emergency braking events (n) out of 100 braking events. b The total distance S traveled by the vehicle, the friction force F between the tires and the ground, the total mass of the vehicle G, and the number of mud spots on the road traversed by the vehicle n. muddy The deepest mud depth H that the vehicle traversed on the road dmax The longest muddy stretch of road that a vehicle has traveled L lmax The height H0 of the active suspension in a stationary state, the height deformation ΔH of the active suspension during driving on a normal road surface, the height deformation ΔH1 of the active suspension during driving on a lightly muddy road surface, the height deformation ΔH2 of the active suspension during driving on a moderately muddy road surface, and the height deformation ΔH3 of the active suspension during driving on a heavily muddy road surface.

[0006] The active suspension performance calculation unit is used to calculate the comprehensive performance index Q of the active suspension, including:

[0007] S1. Establish the active suspension damping force model, and determine the damping force F output by the active suspension. d satisfy:

[0008] F d =Cv d

[0009] Where C represents the damping coefficient, v d This indicates the speed at which the shock absorber spring compresses and extends;

[0010] S2. Calculate the various performance sub-indicators of the active suspension according to the following formulas, including:

[0011] S2.1 Calculate the active suspension state sub-index Q1 according to the following formula:

[0012]

[0013] Where α1, α2, and α3 represent weighting coefficients;

[0014] q 11 This represents the active suspension power source configuration coefficient. When the active suspension power source is an electric motor, q 11 =2.0, when the power source of the active suspension is an electric hydraulic pump, q 11 =1.5, when the power source of the active suspension is an air compressor, q 11 =0.9, other cases, q 11 =0.7;

[0015] q 12 This represents the operating frequency coefficient of the active suspension actuator. When the operating frequency of the active suspension is between 6 and 15 Hz, q 12 =1.6, when the operating frequency band of the active suspension is between 1 and 6 Hz, q 12 =0.8, other cases, q 12 =0.5;

[0016] q 13 q represents the adjustability coefficient of the damping element. When the damping element of the active suspension can be adjusted, q 13 =1.0, when the damping elements of the active suspension cannot be adjusted, q 13 =0.1;

[0017] q 14 q represents the adjustment mode coefficient of the damping element. When the adjustment mode of the damping element is current control, q 14 =1.1, when the damping element is adjusted by a solenoid valve, q 14 =0.9, when the damping element is adjusted by sensor feedback control, q 14 =1.3;

[0018] q 15 represents the difference coefficient of the energy utilization mode of the active suspension. When the active suspension has an energy recovery function, q 15 = 1.2. When the active suspension has no energy recovery function, q 15 = 0.7. When the active suspension has both an energy recovery function and an energy reuse function, q 15 = 2.0;

[0019] S2.2. Calculate the driver's driving state sub-index Q2 according to the following formula:

[0020]

[0021] where, α4 and α5 represent the weight coefficients;

[0022] q 21 represents the driver's vehicle speed control ability coefficient, and its value depends on the vehicle speed. When the driver controls the vehicle speed v on a muddy road surface and satisfies 0 < v ≤ 20 km / h, the driver has good speed control ability, and q 21 = 2.0. When the driver controls the vehicle speed v on a muddy road surface and satisfies 20 < v ≤ 30 km / h, the driver has medium speed control ability, and q 21 = 1.5. When the driver controls the vehicle speed v on a muddy road surface and satisfies v > 30 km / h, the driver has poor speed control ability, and q 21 = 0.5;

[0023] q 22 represents the driver's driving style coefficient, and its value depends on the driver's hard braking rate where, n b represents the number of hard brakes in 100 brakes. When 0 ≤ η < 10, the driver has a stable driving style, and q 22 = 1.0. When 10 ≤ η < 20, the driver has a moderate driving style, and q 22 = 0.7. When η ≥ 20, the driver has an aggressive driving style, and q 22 = 0.4;

[0024] q 23 represents the driving environment coefficient. When the driving environment is daytime and the light is good, q 23 = 1.8. When the driving environment is daytime and the light is poor, q 23 = 1.2. When the driving environment is night, q 23 = 0.7;

[0025] q 24 represents the driver's fatigue degree coefficient. When the driver is slightly fatigued, that is, when the driver yawns, q24 =0.4, when the driver is in a state of moderate fatigue, i.e., the driver experiences eye strain and lower back pain, q 24 =0.6, when the driver is severely fatigued, i.e., experiencing hallucinations and dreams, q 24 =0.8;

[0026] S2.3 Calculate the tire condition sub-index Q3 according to the following formula:

[0027]

[0028] Where α6 and α7 represent weighting coefficients;

[0029] q 31 This refers to the tire pressure coefficient, the value of which depends on the tire pressure P. tire When 0 <P tire When <2.2MPa, q 31 =0.3, when 2.2≤P tire When <2.5MPa, q 31 =0.5, when P tire When ≥2.5MPa, q 31 =0.7;

[0030] q 32 This indicates the tire wear coefficient, and its value depends on the tire wear rate. Where s represents the total distance traveled by the vehicle, and T s This indicates the tire's lifespan. When 0 < ε < 30%, the tire is considered to be in a state of slight wear. q 32 =0.2, when 30≤ε<60%, the tire is at a moderate wear level, q 32 =0.4, when 60≤ε<100%, the tire is in a state of severe wear, q 32 =0.9;

[0031] q 33 q represents the seasonal variation coefficient, which is used when it is spring or autumn. 33 =0.6, when it is summer, q 33 =1.5, when it is winter, q 33 =0.9;

[0032] q 34 The coefficient of friction of a tire indicates its safety factor, and its value depends on the tire's coefficient of adhesion to the ground. Where F represents the frictional force between the tire and the road surface, and G represents the total mass of the vehicle, when At that time, q 34 =0.8, when At that time, q 34 =1.0, when At that time, q34 =1.5;

[0033] S2.4 Calculate the damper condition index Q4 according to the following formula:

[0034]

[0035] Where α8 and α9 represent weighting coefficients;

[0036] q 41 q represents the energy conversion coefficient of the vibration damper. When the vibration damper is a pneumatic vibration damper, q 41 =0.8, when the shock absorber is a hydraulic shock absorber, q 41 =0.6, when the vibration damper is an electromagnetic vibration damper, q 41 =1.2, other cases, q 41 =1.0;

[0037] q 42 q represents the structural coefficient of the vibration damper. When the vibration damper is a monotube hydraulic vibration damper, q 42 =0.9, when the shock absorber is a twin-tube hydraulic shock absorber, q 42 =1.8, other cases, q 42 =1.1;

[0038] q 43 This represents the damping adjustment type coefficient of the shock absorber. When the shock absorber is an adjustable damping shock absorber, q 43 =0.7, when the shock absorber is a height-adjustable shock absorber, q 43 =1.3, other cases, q 43 =0.8;

[0039] q 44 q represents the bearing coefficient of the vibration damper. When the bearing used in the vibration damper is an active vibration damping hydraulic bearing, q 44 =0.4, when the bearing used in the shock absorber is a magnetic levitation bearing, q 44 =0.5, when the bearing used in the shock absorber is an electromagnetic bearing, q 44 =0.6, other cases, q 44 =0.7;

[0040] q 45 q represents the spring material coefficient of the shock absorber. When the spring material used in the shock absorber is carbon spring steel, q 45 =0.6, when the spring material used in the shock absorber is alloy spring steel, q 45 =0.7, when the spring material used in the shock absorber is a non-metallic material, q 45 =0.8;

[0041] S3. Calculate the overall performance index Q of the active suspension according to the following formula:

[0042]

[0043] Among them, ω1, ω2, ω3, and ω4 are the weighted values ​​for individual indicators.

[0044] The muddy road surface condition recognition unit is used to identify the muddy degree of the road surface on which the vehicle is currently traveling. The muddy degree of the road surface is represented by a muddy degree coefficient ξ, which satisfies the formula:

[0045] ξ=γ1ξ1+γ2ξ2+γ3ξ3,0<ξ<1

[0046] Where γ1, γ2, and γ3 represent weight coefficients, and satisfy γ1 + γ2 + γ3 = 1;

[0047] ξ1 represents the road surface mud ratio, and ξ1 satisfies the formula:

[0048]

[0049] Where S represents the total distance traveled by the vehicle, and n muddy This indicates the number of mud spots on the road that the vehicle has traveled;

[0050] ξ2 represents the depth-to-length ratio of a muddy road surface, and ξ2 satisfies the formula:

[0051]

[0052] Among them, H dmax L indicates the deepest mud a vehicle has traversed on the road. lmax This indicates the longest stretch of muddy road a vehicle has traveled.

[0053] ξ3 represents the vehicle throughput on muddy roads, and ξ3 satisfies the formula:

[0054]

[0055] Where N represents the total number of vehicles traveling on the muddy road section, n s This indicates the number of vehicles that successfully navigated the muddy section of road.

[0056] Based on the muddy road surface coefficient ξ, muddy roads can be classified into light muddy roads, moderate muddy roads, and heavy muddy roads. When 0 < ξ ≤ 0.3, the road surface is light muddy; when 0.3 < ξ ≤ 0.6, the road surface is moderate muddy; and when 0.6 < ξ < 1.0, the road surface is heavy muddy.

[0057] The active suspension parameter adjustment unit is used to adjust the parameters of the active suspension according to the mud level of the road surface where the vehicle is currently driving; when the road surface is slightly muddy, the active suspension parameter adjustment unit is in the primary adjustment mode; when the road surface is moderately muddy, the active suspension parameter adjustment unit is in the intermediate adjustment mode; when the road surface is heavily muddy, the active suspension parameter adjustment unit is in the advanced adjustment mode.

[0058] The stiffness K of the active suspension satisfies the formula:

[0059]

[0060] Where, q 45 The spring material coefficient is represented by E, the shear modulus of the spring material is represented by d, and the diameter of the spring is represented by N. e D represents the effective number of coils of the spring. m Indicates the mean diameter of the spring;

[0061] The height H of the active suspension satisfies the formula:

[0062]

[0063] Where ξ3 represents the vehicle throughput on muddy roads, H0 represents the height of the active suspension in a stationary state, and ΔH represents the height deformation of the active suspension during driving on normal roads.

[0064] When the road surface mud coefficient ξ satisfies 0 < ξ ≤ 0.3, the active suspension parameter adjustment unit executes the primary adjustment mode, and the active suspension stiffness K1 satisfies the formula:

[0065]

[0066] Where, q 45 The spring material coefficient is represented by E, the shear modulus of the spring material is represented by d, and the diameter of the spring is represented by N. e D represents the effective number of coils of the spring. m Indicates the mean diameter of the spring;

[0067] The height H1 of the active suspension satisfies the formula:

[0068]

[0069] Where ξ3 represents the vehicle throughput on muddy roads, H0 represents the height of the active suspension in a stationary state, and ΔH1 represents the height deformation of the active suspension during driving on slightly muddy roads.

[0070] The damping force F output by the active suspension d1 Satisfying the formula:

[0071] F d1=e -ξ QCv d

[0072] Where C represents the damping coefficient, v d This indicates the speed at which the shock absorber spring compresses and extends;

[0073] When the road surface mud coefficient ξ satisfies 0.3 < ξ ≤ 0.6, the active suspension parameter adjustment unit executes the intermediate adjustment mode, and the active suspension stiffness K2 satisfies the formula:

[0074]

[0075] Where, q 45 The spring material coefficient is represented by E, the shear modulus of the spring material is represented by d, and the diameter of the spring is represented by N. e D represents the effective number of coils of the spring. m Indicates the mean diameter of the spring;

[0076] The height H2 of the active suspension satisfies the formula:

[0077]

[0078] Where ξ3 represents the vehicle throughput on muddy roads, H0 represents the height of the active suspension in a stationary state, and ΔH2 represents the height deformation of the active suspension during driving on moderately muddy roads.

[0079] The damping force F output by the active suspension d2 Satisfying the formula:

[0080] F d2 =e -ξ Q 2 Cv d

[0081] Where C represents the damping coefficient, v d This indicates the speed at which the shock absorber spring compresses and extends;

[0082] When the road surface mud coefficient ξ satisfies 0.6 < ξ < 1.0, the active suspension parameter adjustment unit executes the advanced adjustment mode, and the active suspension stiffness K3 satisfies the formula:

[0083]

[0084] Where, q 45 The spring material coefficient is represented by E, the shear modulus of the spring material is represented by d, and the diameter of the spring is represented by N. e D represents the effective number of coils of the spring. m Indicates the mean diameter of the spring;

[0085] The height H3 of the active suspension satisfies the formula:

[0086]

[0087] Where ξ3 represents the vehicle throughput on muddy roads, H0 represents the height of the active suspension in a stationary state, and ΔH3 represents the height deformation of the active suspension during driving on heavily muddy roads.

[0088] The damping force F output by the active suspension d3 Satisfying the formula:

[0089] F d3 =e -2ξ Q 2 Cv d

[0090] Where C represents the damping coefficient, v d This indicates the speed at which the shock absorber spring is compressed and stretched.

[0091] The advantages of this invention compared to existing technologies are as follows:

[0092] 1. An adaptive active suspension system based on muddy road surfaces, comprising: a real-time vehicle information acquisition unit, an active suspension performance calculation unit, a muddy road surface condition recognition unit, and an active suspension parameter adjustment unit;

[0093] 2. The muddy road surface condition identification unit of the present invention can classify muddy roads into light muddy roads, moderate muddy roads, and heavy muddy roads according to the muddy road surface degree coefficient ξ; when 0 < ξ ≤ 0.3, the road surface is light muddy road surface; when 0.3 < ξ ≤ 0.6, the road surface is moderate muddy road surface; when 0.6 < ξ < 1.0, the road surface is heavy muddy road surface.

[0094] 3. The active suspension parameter adjustment unit of the present invention is used to adjust the parameters of the active suspension according to the mud level of the road surface on which the vehicle is currently driving; when the road surface is slightly muddy, the active suspension parameter adjustment unit is in the primary adjustment mode; when the road surface is moderately muddy, the active suspension parameter adjustment unit is in the intermediate adjustment mode; when the road surface is heavily muddy, the active suspension parameter adjustment unit is in the advanced adjustment mode. Attached Figure Description

[0095] The present invention will be further described below with reference to the accompanying drawings:

[0096] Figure 1 This is a framework diagram of an adaptive active suspension system based on muddy road surfaces proposed in this invention. Detailed Implementation

[0097] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0098] like Figure 1 As shown, the present invention is an adaptive active suspension system based on muddy road surfaces, comprising: a real-time vehicle information acquisition unit, an active suspension performance calculation unit, a muddy road surface status recognition unit, and an active suspension parameter adjustment unit;

[0099] The vehicle information real-time acquisition unit is used to collect vehicle parameters in real time during the driving process, including: vehicle speed v, and the compression and extension speed v of the shock absorber spring. d The number of emergency braking events (n) out of 100 braking events. b The total distance S traveled by the vehicle, the friction force F between the tires and the ground, the total mass of the vehicle G, and the number of mud spots on the road traversed by the vehicle n. muddy The deepest mud depth H that the vehicle traversed on the road dmax The longest muddy stretch of road that a vehicle has traveled L lmax The height H0 of the active suspension in a stationary state, the height deformation ΔH of the active suspension during driving on a normal road surface, the height deformation ΔH1 of the active suspension during driving on a lightly muddy road surface, the height deformation ΔH2 of the active suspension during driving on a moderately muddy road surface, and the height deformation ΔH3 of the active suspension during driving on a heavily muddy road surface.

[0100] The active suspension performance calculation unit is used to calculate the comprehensive performance index Q of the active suspension, including:

[0101] S1. Establish the active suspension damping force model, and determine the damping force F output by the active suspension. d satisfy:

[0102] F d =Cv d

[0103] Where C represents the damping coefficient, v d This indicates the speed at which the shock absorber spring compresses and extends;

[0104] S2. Calculate the various performance sub-indicators of the active suspension according to the following formulas, including:

[0105] S2.1 Calculate the active suspension state sub-index Q1 according to the following formula:

[0106]

[0107] Where α1, α2, and α3 represent weighting coefficients;

[0108] q 11 This represents the active suspension power source configuration coefficient. When the active suspension power source is an electric motor, q 11 =2.0, when the power source of the active suspension is an electric hydraulic pump, q11 = 1.5. When the power source of the active suspension is an air compressor, q 11 = 0.9. In other cases, q 11 = 0.7;

[0109] q 12 represents the working frequency band coefficient of the active suspension actuator. When the working frequency band of the active suspension is 6 - 15 Hz, q 12 = 1.6. When the working frequency band of the active suspension is 1 - 6 Hz, q 12 = 0.8. In other cases, q 12 = 0.5;

[0110] q 13 represents the adjustability coefficient of the damping element. When the damping element of the active suspension can be adjusted, q 13 = 1.0. When the damping element of the active suspension cannot be adjusted, q 13 = 0.1;

[0111] q 14 represents the adjustment method coefficient of the damping element. When the adjustment method of the damping element is current control, q 14 = 1.1. When the adjustment method of the damping element is solenoid valve control, q 14 = 0.9. When the adjustment method of the damping element is sensor feedback control, q 14 = 1.3;

[0112] q 15 represents the difference coefficient of the energy utilization method of the active suspension. When the active suspension has an energy recovery function, q 15 = 1.2. When the active suspension has no energy recovery function, q 15 = 0.7. When the active suspension has both an energy recovery function and an energy reuse function, q 15 = 2.0;

[0113] S2.2. Calculate the driver's driving state sub - index Q2 according to the following formula:

[0114]

[0115] where, α4, α5 represent the weight coefficients;

[0116] q 21 represents the driver's vehicle speed control ability coefficient, and its value depends on the vehicle speed. When the driver controls the vehicle speed v on a muddy road surface and satisfies 0 < v ≤ 20 km / h, the driver has good speed control ability, q 21 = 2.0. When the driver controls the vehicle speed v on a muddy road surface and satisfies 20 < v ≤ 30 km / h, the driver has medium speed control ability, q21 =1.5. When the driver controls the vehicle speed v on a muddy road to satisfy v>30km / h, the driver has poor speed control ability. q 21 =0.5;

[0117] q 22 This represents the driver's driving style coefficient, the value of which depends on the driver's rate of emergency braking. Where nb represents the number of emergency braking events out of 100 braking events, and when 0 ≤ η < 10, the driver has a stable driving style. 22 =1.0, when 10≤η<20, then the driver has a moderate driving style, q 22 =0.7, when η≥20, the driver has an aggressive driving style, q 22 =0.4;

[0118] q 23 q represents the driving environment coefficient, which is calculated under daytime and good lighting conditions. 23 =1.8, when the driving environment is daytime and the lighting conditions are poor, q 23 =1.2, when the driving environment is nighttime, q 23 =0.7;

[0119] q 24 This represents the driver fatigue level coefficient. When the driver is mildly fatigued, i.e., when the driver yawns, q represents the driver fatigue level. 24 =0.4, when the driver is in a state of moderate fatigue, i.e., the driver experiences eye strain and lower back pain, q 24 =0.6, when the driver is severely fatigued, i.e., experiencing hallucinations and dreams, q 24 =0.8;

[0120] S2.3 Calculate the tire condition sub-index Q3 according to the following formula:

[0121]

[0122] Where α6 and α7 represent weighting coefficients;

[0123] q 31 This refers to the tire pressure coefficient, the value of which depends on the tire pressure P. tire When 0 <P tire When <2.2MPa, q 31 =0.3, when 2.2≤P tire When <2.5MPa, q 31 =0.5, when P tire When ≥2.5MPa, q 31 =0.7;

[0124] q 32 This indicates the tire wear coefficient, and its value depends on the tire wear rate. Where S represents the total distance traveled by the vehicle, and T s This indicates the tire's lifespan. When 0 < ε < 30%, the tire is considered to be in a state of slight wear. q 32 =0.2, when 30≤ε<60%, the tire is at a moderate wear level, q 32 =0.4, when 60≤ε<100%, the tire is in a state of severe wear, q 32 =0.9;

[0125] q 33 q represents the seasonal variation coefficient, which is used when it is spring or autumn. 33 =0.6, when it is summer, q 33 =1.5, when it is winter, q 33 =0.9;

[0126] q 34 The coefficient of friction of a tire indicates its safety factor, and its value depends on the tire's coefficient of adhesion to the ground. Where F represents the frictional force between the tire and the road surface, and G represents the total mass of the vehicle, when At that time, q 34 =0.8, when At that time, q 34 =1.0, when At that time, q 34 =1.5;

[0127] S2.4 Calculate the damper condition index Q4 according to the following formula:

[0128]

[0129] Where α8 and α9 represent weighting coefficients;

[0130] q 41 q represents the energy conversion coefficient of the vibration damper. When the vibration damper is a pneumatic vibration damper, q 41 =0.8, when the shock absorber is a hydraulic shock absorber, q 41 =0.6, when the vibration damper is an electromagnetic vibration damper, q 41 =1.2, other cases, q 41 =1.0;

[0131] q 42 q represents the structural coefficient of the vibration damper. When the vibration damper is a monotube hydraulic vibration damper, q 42 =0.9, when the shock absorber is a twin-tube hydraulic shock absorber, q 42 =1.8, other cases, q 42 =1.1;

[0132] q 43 This represents the damping adjustment type coefficient of the shock absorber. When the shock absorber is an adjustable damping shock absorber, q 43 =0.7, when the shock absorber is a height-adjustable shock absorber, q 43 =1.3, other cases, q 43 =0.8;

[0133] q 44 q represents the bearing coefficient of the vibration damper. When the bearing used in the vibration damper is an active vibration damping hydraulic bearing, q 44 =0.4, when the bearing used in the shock absorber is a magnetic levitation bearing, q 44 =0.5, when the bearing used in the shock absorber is an electromagnetic bearing, q 44 =0.6, other cases, q 44 =0.7;

[0134] q 45 q represents the spring material coefficient of the shock absorber. When the spring material used in the shock absorber is carbon spring steel, q 45 =0.6, when the spring material used in the shock absorber is alloy spring steel, q 45 =0.7, when the spring material used in the shock absorber is a non-metallic material, q 45 =0.8;

[0135] S3. Calculate the overall performance index Q of the active suspension according to the following formula:

[0136]

[0137] Among them, ω1, ω2, ω3, and ω4 are the weighted values ​​for individual indicators.

[0138] The muddy road surface condition recognition unit is used to identify the muddy degree of the road surface on which the vehicle is currently traveling. The muddy degree of the road surface is represented by a muddy degree coefficient ξ, which satisfies the formula:

[0139] ξ=γ1ξ1+γ2ξ2+γ3ξ3,0<ξ<1

[0140] Where γ1, γ2, and γ3 represent weight coefficients, and satisfy γ1 + γ2 + γ3 = 1;

[0141] ξ1 represents the road surface mud ratio, and ξ1 satisfies the formula:

[0142]

[0143] Where S represents the total distance traveled by the vehicle, and n muddy This indicates the number of mud spots on the road that the vehicle has traveled;

[0144] ξ2 represents the depth-to-length ratio of a muddy road surface, and ξ2 satisfies the formula:

[0145]

[0146] Among them, H dmax L indicates the deepest mud a vehicle has traversed on the road. lmax This indicates the longest stretch of muddy road a vehicle has traveled.

[0147] ξ3 represents the vehicle throughput on muddy roads, and ξ3 satisfies the formula:

[0148]

[0149] Where N represents the total number of vehicles traveling on the muddy road section, n s This indicates the number of vehicles that successfully navigated the muddy section of road.

[0150] Based on the muddy road surface coefficient ξ, muddy roads can be classified into light muddy roads, moderate muddy roads, and heavy muddy roads. When 0 < ξ ≤ 0.3, the road surface is light muddy; when 0.3 < ξ ≤ 0.6, the road surface is moderate muddy; and when 0.6 < ξ < 1.0, the road surface is heavy muddy.

[0151] The active suspension parameter adjustment unit is used to adjust the parameters of the active suspension according to the mud level of the road surface where the vehicle is currently driving; when the road surface is slightly muddy, the active suspension parameter adjustment unit is in the primary adjustment mode; when the road surface is moderately muddy, the active suspension parameter adjustment unit is in the intermediate adjustment mode; when the road surface is heavily muddy, the active suspension parameter adjustment unit is in the advanced adjustment mode.

[0152] The stiffness K of the active suspension satisfies the formula:

[0153]

[0154] Where, q 45 The spring material coefficient is represented by E, the shear modulus of the spring material is represented by d, and the diameter of the spring is represented by N. e D represents the effective number of coils of the spring. m Indicates the mean diameter of the spring;

[0155] The height H of the active suspension satisfies the formula:

[0156]

[0157] Where ξ3 represents the vehicle throughput on muddy roads, H0 represents the height of the active suspension in a stationary state, and ΔH represents the height deformation of the active suspension during driving on normal roads.

[0158] When the road surface mud coefficient ξ satisfies 0 < ξ ≤ 0.3, the active suspension parameter adjustment unit executes the primary adjustment mode, and the active suspension stiffness K1 satisfies the formula:

[0159]

[0160] Where, q 45 The spring material coefficient is represented by E, the shear modulus of the spring material is represented by d, and the diameter of the spring is represented by N. e D represents the effective number of coils of the spring. m Indicates the mean diameter of the spring;

[0161] The height H1 of the active suspension satisfies the formula:

[0162]

[0163] Where ξ3 represents the vehicle throughput on muddy roads, H0 represents the height of the active suspension in a stationary state, and ΔH1 represents the height deformation of the active suspension during driving on slightly muddy roads.

[0164] The damping force F output by the active suspension d1 Satisfying the formula:

[0165] F d1 =e -ξ QCv d

[0166] Where C represents the damping coefficient, v d This indicates the speed at which the shock absorber spring compresses and extends;

[0167] When the road surface mud coefficient ξ satisfies 0.3 < ξ ≤ 0.6, the active suspension parameter adjustment unit executes the intermediate adjustment mode, and the active suspension stiffness K2 satisfies the formula:

[0168]

[0169] Where, q 45 The spring material coefficient is represented by E, the shear modulus of the spring material is represented by d, and the diameter of the spring is represented by N. e D represents the effective number of coils of the spring. m Indicates the mean diameter of the spring;

[0170] The height H2 of the active suspension satisfies the formula:

[0171]

[0172] Where ξ3 represents the vehicle throughput on muddy roads, H0 represents the height of the active suspension in a stationary state, and ΔH2 represents the height deformation of the active suspension during driving on moderately muddy roads.

[0173] The damping force F output by the active suspension d2 Satisfying the formula:

[0174] F d2 =e -ξ Q 2 Cv d

[0175] Where C represents the damping coefficient, v d This indicates the speed at which the shock absorber spring compresses and extends;

[0176] When the road surface mud coefficient ξ satisfies 0.6 < ξ < 1.0, the active suspension parameter adjustment unit executes the advanced adjustment mode, and the active suspension stiffness K3 satisfies the formula:

[0177]

[0178] Where, q 45 The spring material coefficient is represented by E, the shear modulus of the spring material is represented by d, and the diameter of the spring is represented by N. e D represents the effective number of coils of the spring. m Indicates the mean diameter of the spring;

[0179] The height H3 of the active suspension satisfies the formula:

[0180]

[0181] Where ξ3 represents the vehicle throughput on muddy roads, H0 represents the height of the active suspension in a stationary state, and ΔH3 represents the height deformation of the active suspension during driving on heavily muddy roads.

[0182] The damping force F output by the active suspension d3 Satisfying the formula:

[0183] F d3 =e -2ξ Q 2 Cvv d

[0184] Where C represents the damping coefficient, v d This indicates the speed at which the shock absorber spring is compressed and stretched.

Claims

1. An adaptive active suspension system for muddy road surfaces, characterized in that, Includes the following: Vehicle information real-time acquisition unit, active suspension performance calculation unit, muddy road surface condition recognition unit, and active suspension parameter adjustment unit; The vehicle information real-time acquisition unit is used to collect vehicle parameters in real time during the driving process, including: vehicle speed v, and the compression and extension speed v of the shock absorber spring. d The number of emergency braking events (n) out of 100 braking events. b The total distance S traveled by the vehicle, the friction force F between the tires and the ground, the total mass of the vehicle G, and the number of mud spots on the road traversed by the vehicle n. muddy The deepest mud depth H that the vehicle traversed on the road dmax The longest muddy stretch of road that a vehicle has traveled L lmax The height H0 of the active suspension in a stationary state, the height deformation ΔH of the active suspension during driving on a normal road surface, the height deformation ΔH1 of the active suspension during driving on a lightly muddy road surface, the height deformation ΔH2 of the active suspension during driving on a moderately muddy road surface, and the height deformation ΔH3 of the active suspension during driving on a heavily muddy road surface. The active suspension performance calculation unit is used to calculate the comprehensive performance index Q of the active suspension, including: S1. Establish the active suspension damping force model, and determine the damping force F output by the active suspension. d satisfy: F d =Cv d Where C represents the damping coefficient, v d This indicates the speed at which the shock absorber spring compresses and extends; S2. Calculate the various performance sub-indicators of the active suspension according to the following formulas, including: S2.1 Calculate the active suspension state sub-index Q1 according to the following formula: Where α1, α2, and α3 represent weighting coefficients; q 11 This represents the active suspension power source configuration coefficient. When the active suspension power source is an electric motor, q 11 =2.0, when the power source of the active suspension is an electric hydraulic pump, q 11 =1.5, when the power source of the active suspension is an air compressor, q 11 =0.9, other cases, q 11 =0.7; q 12 This represents the operating frequency coefficient of the active suspension actuator. When the operating frequency of the active suspension is between 6 and 15 Hz, q 12 =1.6, when the operating frequency band of the active suspension is between 1 and 6 Hz, q 12 =0.8, other cases, q 12 =0.5; q 13 q represents the adjustability coefficient of the damping element. When the damping element of the active suspension can be adjusted, q 13 =1.0, when the damping elements of the active suspension cannot be adjusted, q 13 =0.1; q 14 q represents the adjustment mode coefficient of the damping element. When the adjustment mode of the damping element is current control, q 14 =1.1, when the damping element is adjusted by a solenoid valve, q 14 =0.9, when the damping element is adjusted by sensor feedback control, q 14 =1.3; q 15 q represents the difference coefficient in energy utilization methods of active suspension. When the active suspension has an energy recovery function, q 15 =1.2, when the active suspension does not have energy recovery function, q 15 =0.7, when the active suspension has both energy recovery and energy reuse functions, q 15 =2.0; S2.2 Calculate the driver's driving status sub-index Q2 according to the following formula: Where α4 and α5 represent weighting coefficients; q 21 Represents the coefficient of the driver's vehicle speed control ability, whose value depends on the magnitude of the vehicle speed. When the driver controls the vehicle speed v on a muddy road surface and satisfies 0 < v ≤ 20 km / h, the driver has good speed control ability, q 21 = 2.

0. When the driver controls the vehicle speed v on a muddy road surface and satisfies 20 < v ≤ 30 km / h, the driver has medium speed control ability, q 21 = 1.

5. When the driver controls the vehicle speed v on a muddy road surface and satisfies v > 30 km / h, the driver has poor speed control ability, q 21 = 0.5; q 22 This represents the driver's driving style coefficient, the value of which depends on the driver's rate of emergency braking. Where, n b This represents the number of emergency braking actions out of 100 braking attempts. When 0 ≤ η < 10, the driver has a stable driving style. 22 =1.0, when 10≤η<20, then the driver has a moderate driving style, q 22 =0.7, when η≥20, the driver has an aggressive driving style, q 22 =0.4; q 23 q represents the driving environment coefficient, which is calculated under daytime and good lighting conditions. 23 =1.8, when the driving environment is daytime and the lighting conditions are poor, q 23 =1.2, when the driving environment is nighttime, q 23 =0.7; q 24 This represents the driver fatigue level coefficient. When the driver is mildly fatigued, i.e., when the driver yawns, q represents the driver fatigue level. 24 =0.4, when the driver is in a state of moderate fatigue, i.e., the driver experiences eye strain and lower back pain, q 24 =0.6, when the driver is severely fatigued, i.e., experiencing hallucinations and dreams, q 24 =0.8; S2.3 Calculate the tire condition sub-index Q3 according to the following formula: Where α6 and α7 represent weighting coefficients; q 31 represents the tire pressure coefficient, whose value depends on the tire pressure P tire , when 0 < Ptire < 2.2 MPa, q 31 = 0.3, when 2.2 ≤ P tire < 2.5 MPa, q 31 = 0.5, when P tire ≥ 2.5 MPa, q 31 = 0.7; q 32 This indicates the tire wear coefficient, and its value depends on the tire wear rate. Where S represents the total distance traveled by the vehicle, and T s This indicates the tire's lifespan. When 0 < ε < 30%, the tire is considered to be in a state of slight wear. q 32 =0.2, when 30≤ε<60%, the tire is at a moderate wear level, q 32 =0.4, when 60≤ε<100%, the tire is in a state of severe wear, q 32 =0.9; q 33 q represents the seasonal variation coefficient, which is used when it is spring or autumn. 33 =0.6, when it is summer, q 33 =1.5, when it is winter, q 33 =0.9; q 34 The coefficient of friction of a tire indicates its safety factor, and its value depends on the tire's coefficient of adhesion to the ground. Where F represents the frictional force between the tire and the road surface, and G represents the total mass of the vehicle, when At that time, q 34 =0.8, when At that time, q 34 =1.0, when At that time, q 34 =1.5; S2.4 Calculate the damper condition index Q4 according to the following formula: Where α8 and α9 represent weighting coefficients; q 41 q represents the energy conversion coefficient of the vibration damper. When the vibration damper is a pneumatic vibration damper, q 41 =0.8, when the shock absorber is a hydraulic shock absorber, q 41 =0.6, when the vibration damper is an electromagnetic vibration damper, q 41 =1.2, other cases, q 41 =1.0; q 42 q represents the structural coefficient of the vibration damper. When the vibration damper is a monotube hydraulic vibration damper, q 42 =0.9, when the shock absorber is a twin-tube hydraulic shock absorber, q 42 =1.8, other cases, q 42 =1.1; q 43 This represents the damping adjustment type coefficient of the shock absorber. When the shock absorber is an adjustable damping shock absorber, q 43 =0.7, when the shock absorber is a height-adjustable shock absorber, q 43 =1.3, other cases, q 43 =0.8; q 44 q represents the bearing coefficient of the vibration damper. When the bearing used in the vibration damper is an active vibration damping hydraulic bearing, q 44 =0.4, when the bearing used in the shock absorber is a magnetic levitation bearing, q 44 =0.5, when the bearing used in the shock absorber is an electromagnetic bearing, q 44 =0.6, other cases, q 44 =0.7; q 45 q represents the spring material coefficient of the shock absorber. When the spring material used in the shock absorber is carbon spring steel, q 45 =0.6, when the spring material used in the shock absorber is alloy spring steel, q 45 =0.7, when the spring material used in the shock absorber is a non-metallic material, q 45 =0.8; S3. Calculate the overall performance index Q of the active suspension according to the following formula: Among them, ω1, ω2, ω3, and ω4 are the weighted values ​​for individual indicators.

2. The adaptive active suspension system based on muddy road surfaces according to claim 1, characterized in that, The muddy road surface condition recognition unit is used to identify the muddy degree of the road surface on which the vehicle is currently traveling. The muddy degree of the road surface is represented by a muddy degree coefficient ξ, which satisfies the formula: ξ=γ1ξ1+γ2ξ2+γ3ξ3, 0<ξ<1 Where γ1, γ2, and γ3 represent weight coefficients, and satisfy γ1 + γ2 + γ3 = 1; ξ1 represents the road surface mud ratio, and ξ1 satisfies the formula: Where S represents the total distance traveled by the vehicle, and n muddy This indicates the number of mud spots on the road that the vehicle has traveled; ξ2 represents the depth-to-length ratio of a muddy road surface, and ξ2 satisfies the formula: Among them, H dmax L indicates the deepest mud a vehicle has traversed on the road. lmax This indicates the longest stretch of muddy road a vehicle has traveled. ξ3 represents the vehicle throughput on muddy roads, and ξ3 satisfies the formula: Where N represents the total number of vehicles traveling on the muddy road section, n s This indicates the number of vehicles that successfully navigated the muddy section of road.

3. The adaptive active suspension system based on muddy road surfaces according to claim 2, characterized in that, Based on the muddy road surface coefficient ξ, muddy roads can be classified into light muddy roads, moderate muddy roads, and heavy muddy roads. When 0 < ξ ≤ 0.3, the road surface is light muddy; when 0.3 < ξ ≤ 0.6, the road surface is moderate muddy; and when 0.6 < ξ < 1.0, the road surface is heavy muddy.

4. The adaptive active suspension system based on muddy road surfaces according to claim 1, characterized in that, The active suspension parameter adjustment unit is used to adjust the parameters of the active suspension according to the mud level of the road surface where the vehicle is currently driving; when the road surface is slightly muddy, the active suspension parameter adjustment unit is in the primary adjustment mode; when the road surface is moderately muddy, the active suspension parameter adjustment unit is in the intermediate adjustment mode; when the road surface is heavily muddy, the active suspension parameter adjustment unit is in the advanced adjustment mode. The stiffness K of the active suspension satisfies the formula: Where, q 45 The spring material coefficient is represented by E, the shear modulus of the spring material is represented by d, and the diameter of the spring is represented by N. e D represents the effective number of coils of the spring. m Indicates the mean diameter of the spring; The height H of the active suspension satisfies the formula: Where ξ3 represents the vehicle throughput on muddy roads, H0 represents the height of the active suspension in a stationary state, and ΔH represents the height deformation of the active suspension during driving on normal roads.

5. The adaptive active suspension system based on muddy road surfaces according to claim 4, characterized in that, When the road surface mud coefficient ξ satisfies 0 < ξ ≤ 0.3, the active suspension parameter adjustment unit executes the primary adjustment mode, and the active suspension stiffness K1 satisfies the formula: Where, q 45 The spring material coefficient is represented by E, the shear modulus of the spring material is represented by d, and the diameter of the spring is represented by N. e D represents the effective number of coils of the spring. m Indicates the mean diameter of the spring; The height H1 of the active suspension satisfies the formula: Where ξ3 represents the vehicle throughput on muddy roads, H0 represents the height of the active suspension in a stationary state, and ΔH1 represents the height deformation of the active suspension during driving on slightly muddy roads. The damping force F output by the active suspension d1 Satisfying the formula: F d1 =e -ξ QCv d Where C represents the damping coefficient, v d This indicates the speed at which the shock absorber spring compresses and extends; When the road surface mud coefficient ξ satisfies 0.3 < ξ ≤ 0.6, the active suspension parameter adjustment unit executes the intermediate adjustment mode, and the active suspension stiffness K2 satisfies the formula: Where, q 45 The spring material coefficient is represented by E, the shear modulus of the spring material is represented by d, and the diameter of the spring is represented by N. e D represents the effective number of coils of the spring. m Indicates the mean diameter of the spring; The height H2 of the active suspension satisfies the formula: Where ξ3 represents the vehicle throughput on muddy roads, H0 represents the height of the active suspension in a stationary state, and ΔH2 represents the height deformation of the active suspension during driving on moderately muddy roads. The damping force F output by the active suspension d2 Satisfying the formula: F d2 =e -ξ Q 2 Cv d Where C represents the damping coefficient, v d This indicates the speed at which the shock absorber spring compresses and extends; When the road surface mud coefficient ξ satisfies 0.6 < ξ < 1.0, the active suspension parameter adjustment unit executes the advanced adjustment mode, and the active suspension stiffness K3 satisfies the formula: Where, q 45 The spring material coefficient is represented by E, the shear modulus of the spring material is represented by d, and the diameter of the spring is represented by N. e D represents the effective number of coils of the spring. m Indicates the mean diameter of the spring; The height H3 of the active suspension satisfies the formula: Where ξ3 represents the vehicle throughput on muddy roads, H0 represents the height of the active suspension in a stationary state, and ΔH3 represents the height deformation of the active suspension during driving on heavily muddy roads. The damping force F output by the active suspension d3 Satisfying the formula: F d3 =e -2ξ Q 2 Cv d Where C represents the damping coefficient, v d This indicates the speed at which the shock absorber spring is compressed and stretched.

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