Calibration Method for Non-standard Parabolic Guide Arm Air Suspension System

Abstract

The present invention relates to a calibration method for a non-standard parabolic guide arm air suspension system, belonging to the technical field of trailer air suspension. The present invention includes a guide arm assembly and an airbag, wherein the guide arm assembly includes a front guide arm and an airbag support arm; the front guide arm is composed of a straight root section, a parabolic section, and a straight end section. The following calibration steps are used: the clamping flexibility R of the front guide arm is db Calculation of the clamping flexibility R of the airbag support arm da Calculation of clamping stiffness K z Verification calculation, composite stiffness K C The present invention uses prototype vehicle testing to ensure that the key parameters of a non-standard parabolic guide-arm air suspension system meet design requirements, improving the design level of the trailer air suspension system and the vehicle's ride smoothness and safety. It also reduces design and testing costs and accelerates product development.

Description

Technical Field

[0001] The invention relates to a calibration method for a non-standard parabolic guide arm type air suspension system, belonging to the technical field of trailer air suspension. Background Art

[0002] Trailer air suspension primarily consists of a guide arm assembly, airbag, and shock absorber components. The guide arm assembly, including the airbag, consists of a front guide arm and an airbag support arm. The front guide arm can be two-piece or a single piece, while the airbag support arm is a single piece. To meet installation and end-mounted lug strength requirements, the end thickness and length of the front guide arm and airbag support arm are typically specified. This results in the coordinate origin of the parabolic thickness variation pattern of the front guide arm not being at the end point of the front guide arm, resulting in a certain coordinate offset. This means that the cross-section of the non-standard parabolic guide arm assembly typically has three end shapes: arc, right angle, and chamfer. Due to the structural asymmetry of the guide arm assembly—namely, the front guide arm and the airbag support arm are unequal in length, and the offset in cross-sectional shape and parabolic coordinates—this affects the stiffness of each front guide arm segment, the clamping stiffness of the guide arm assembly, and the calculation of the composite stiffness of the air suspension system. This impacts the air suspension system's suspension frequency deviation, damping matching, end loads, and stress intensity, ultimately affecting vehicle ride smoothness and safety. While considering the offset in cross-sectional shape and parabolic coordinates of the guide arm, and their impact on clamping stiffness, accurate and reliable calibration methods for non-standard parabolic guide arm air suspension systems have been limited, both domestically and internationally. In order to meet the rapid development of the vehicle industry and the requirements for air suspension system calibration, and to ensure that the suspension frequency deviation, damping ratio, and stress intensity of the air suspension system meet the design requirements, it is necessary to establish an accurate and reliable calibration method for non-standard parabolic guide arm air suspension systems, improve the calibration level of the air suspension system and the vehicle's ride smoothness and safety; at the same time, reduce calibration and testing costs and accelerate product development. Summary of the Invention

[0003] In view of the above-mentioned defects in the prior art, the technical problem to be solved by the present invention is to provide an accurate and reliable calibration method for a non-standard parabolic guide arm air suspension system. The calibration process is as follows: Figure 1 The air suspension guide arm assembly is an asymmetric structure consisting of a front guide arm and an airbag support arm. The width is B, the elastic modulus is E, the clamping distance of the riding bolt is U, and the load of the guide arm assembly is P. N , the end load of the front guide arm is F b , the end load of the airbag support arm is F a , its structural diagram and mechanical model, such as Figure 2 As shown, the length of the front guide arm is Lb The number of the front guide arm is n, usually a single piece or two pieces, that is: n = 1 or n = 2. The thickness of the straight section at the root of each front guide arm is h 2i The length of the straight section at the root is L2; the thickness of the straight section at the end of each front guide arm is h 1i The length of the straight section at the end is L 1i ; The length L from the root to the end point of the parabola segment of each front guide arm 2p , the length of the parabola segment is L pi , the thickness of the parabola segment is greater than β i =h 1i / h 2i , i=1,2,…,n. The length of the airbag support arm is L a , usually the airbag support arm is a single piece, that is, n a =1, the thickness of the straight section at the root of the airbag support arm is h 2a The thickness of the straight section outside the vertical arm is h 21a The thickness of the straight section at the end of the airbag support arm is h 1a , the thickness ratio of the parabola segment of the airbag support arm is β a =h 1a / h 21a , the vertical arm height of the airbag support arm is h z2 The length of the straight section at the root of the airbag support arm is L 22a The length of the vertical arm is L z2 The length of the straight section outside the vertical arm is L 21a , the length of the parabola segment of the airbag support arm is L pa , that is: the length from the root of the parabola segment to the center of the airbag installation. The shapes of the two ends of the guide arm cross section are arc, chamfered and right angle. Figure 3 For three different cross-section types, the ratio of chamfer radius to thickness k can be used r =r / h unified representation, 0≤r≤h / 2, 0≤k r ≤1 / 2, where r=h / 2, k r =1 / 2, the cross section is arc-shaped; when r=0, k r =0, the cross section is rectangular; when 0 <r<h / 2,0<k r <1 / 2, chamfered cross section. To meet the requirements of installation and end lug strength, the thickness and length of the straight section at the end of the guide arm are usually given, and L 1i ≠L 2p β i 2Therefore, the coordinate origin of the parabolic segment's thickness variation pattern does not coincide with the endpoint of the guide arm, resulting in a coordinate offset. This indicates that the parabola segment is non-standard. Based on the structural parameters, rated load, and allowable stress of the non-standard parabolic guide arm assembly, the airbag's stiffness under rated load, the shock absorber's damping coefficient, and its installation angle, the composite stiffness, suspension offset frequency, suspension system damping ratio, and guide arm stress intensity of the non-standard parabolic guide arm air suspension system were verified to ensure that the key parameters of the non-standard parabolic guide arm air suspension system met design requirements.

[0004] To solve the above technical problems, the present invention provides a calibration method for a non-standard parabolic guiding arm air suspension system, which is characterized by adopting the following calibration steps:

[0005] S1: Clamping flexibility R of the front guide arm of the non-standard parabolic guide arm assembly db Calculation:

[0006] S11: Load distribution ratio coefficient k of front guide arm and airbag support arm Fb and k Fa Calculation:

[0007] According to the front guide arm length L b , the length of the airbag support arm L a , the load distribution ratio coefficient k for the front guide arm and airbag support arm of the guide arm assembly Fb and k Fa Calculate separately,

[0008]

[0009] S12: Equivalent width b of the straight section at the root and end of each front guide arm 2i and b 1i Calculation:

[0010] According to the guide arm width B, the chamfer radius thickness ratio k at both ends of the cross section r , 0≤k r ≤1 / 2, number of front guide arms n, thickness of the straight section at the root of each front guide arm h 2i and the thickness of the straight section at the end h 1i , the equivalent width b of the straight section at the root of each front guide arm 2i and the equivalent width b of the straight section at the end 1i Calculate, i=1,2,…,n, that is:

[0011] b 2i =B+h 2i D br ; b 1i =B+h1i D br ;

[0012] Where: is the equivalent width reduction coefficient, where 0≤k r ≤1 / 2, then -0.411≤D br ≤0,;

[0013] When k r =1 / 2, D br =-0.411, the cross section is arc-shaped, then b 2i =B-0.411h 2i , b 1i =B-0.411h 1i ;

[0014] When k r =0,D br =0, the cross section is rectangular, then D br =0, then b 2i =B, b 1i =B;

[0015] S13: Parabola segment coordinate translation x of each non-standard parabola front guide arm 0i Calculation:

[0016] According to the number of front guide arm pieces n, the thickness of the straight section at the root of each front guide arm is h 2i , the thickness of the straight section at the end h 1i , the length of the straight section at the end is L 1i , the length L from the root of the parabola segment to the end point of the guide arm 2p , and the thickness ratio of the parabola segment β i =h 1i / h 2i , the parabola segment coordinate offset x of each non-standard parabola front guide arm 0i Calculate, i=1,…,n, that is

[0017]

[0018] S14: Flexibility R of the straight section at the end of each non-standard parabolic front guide arm d1i Calculation:

[0019] According to the number of front guide arms n, the h of each front guide arm 1i , L 1i , elastic modulus E, k calculated in S11 Fb , b calculated in S12 1i , the flexibility R of the straight section at the end of each non-standard parabolic front guide arm d1iCalculate, i=1,2,…,n, that is:

[0020]

[0021] S15: Clamping flexibility R of the straight section at the root of each non-standard parabolic front guide arm d2i Calculation:

[0022] According to the number of front guide arms n, the h of each front guide arm 2i , L b , L 2p , saddle bolt clamping distance U, elastic modulus E, k calculated in S11 Fb , b calculated in S12 2i , the clamping flexibility R of the straight section at the root of each non-standard parabolic front guide arm d2i Calculate, i=1,2,…,n, that is:

[0023]

[0024] S16: Parabolic segment flexibility R of each non-standard parabolic front guide arm dpi Calculation:

[0025] S161: cross-section chamfered type, i.e.: k r ≠0

[0026] According to the guide arm width B, the cross-section is chamfered, that is: k r ≠0,0 <k r ≤1 / 2, -0.41≤D br <0, elastic modulus E; number of front guide arms n, L of each front guide arm 2p , L 1i , h 2i , h 1i , β i =h 1i / h 2i ; k calculated in S11 Fb , b calculated in S12 2i , b 1i , x calculated in S13 0i , the parabolic segment flexibility R of each non-standard parabolic front end guide arm with chamfered cross section dpi Calculate, i=1,2,…,n, that is:

[0027]

[0028] Where: G Rdpi is the flexibility coefficient of the parabolic segment of the i-th non-standard parabolic front end guide arm with chamfered cross section, that is:

[0029]

[0030] Among them, L 2pTi is the length from the root of the parabola segment to the origin of the coordinate system, L 2pTi =L 2p +x 0i ;

[0031] S162: rectangular cross section, i.e.: k r =0

[0032] According to the guide arm width B, the cross section is a right angle type k r =0, elastic modulus E; number of front guide arms n, L of each front guide arm 2p , L 1i , h 2i , h 1i , β i =h 1i / h 2i , x calculated in S13 0i , the parabolic segment flexibility R of each non-standard parabolic front end guide arm with a right-angle cross section dpi It can be expressed as

[0033]

[0034] Where: G Rdp_ZJi is the flexibility coefficient of the parabolic segment of the i-th non-standard parabolic front end guide arm with a right-angle cross section, that is:

[0035] S17: Clamping flexibility R of each non-standard parabolic front guide arm dbi Calculation:

[0036] According to the number of front guide arm pieces n, R calculated in S14 d1i , R calculated in S15 d2i , R calculated in S16 dpi , the clamping flexibility R of each non-standard parabolic front guide arm dbi Calculate, i=1,2,…,n, that is:

[0037] R dbi =R d2i +R d1i +R dpi , i=1,2,..,n;

[0038] S18: Clamping stiffness K of non-standard parabolic front guide arm b and clamping flexibility R db Calculation:

[0039] According to the number of front guide arm pieces n, R calculated in S17 dbi , the clamping stiffness K of the non-standard parabolic front guide arm b and clamping flexibility R db Perform the calculation, namely:

[0040]

[0041] S2: Clamping flexibility R of the airbag support arm of the non-standard parabolic end guide arm assembly da Calculation:

[0042] S21: Calculation of the equivalent width of each section of the airbag support arm:

[0043] According to the guide arm width B, the chamfer radius thickness ratio k at both ends of the cross section r , 0≤k r ≤1 / 2, equivalent width reduction factor D br , -0.411≤D br ≤0, the thickness of the straight section at the root of the airbag support arm h 2a , the length of the vertical arm L z2 =h 2a , the thickness of the straight section outside the vertical arm h 21a =h 2a , the thickness h of the parabolic end of the airbag support arm 1a ; Equivalent width b of the straight section at the root of the airbag support arm 2a , the equivalent width b of the boom section za , the equivalent width b of the straight section outside the drop arm 21a , the equivalent width b at the end of the parabola segment 1a Perform the calculation, namely:

[0044] b 2a =B+h 2a D br , b za =B+L z2 D br , b 21a =B+h 21a D br , b 1a =B+h 1a D br ;

[0045] When k r =1 / 2, arc cross section, D br =-0.411, then b 2a =B-0.411h 2a , b za =B-0.411Lz2 ,

[0046] b 21a =B-0.411h 21a , b 1a =B-0.411h 1a ;

[0047] When k r =0, rectangular cross section, D br =0, then b 2a =B, b za =B, b 21a =B, b 1a =B;

[0048] S22: Flexibility R of the parabolic segment of the non-standard parabolic airbag support arm dpa Calculation:

[0049] S221: cross-section chamfered type, i.e.: k r ≠0

[0050] According to the guide arm width B, cross-section chamfer type, k r ≠0,0 <k r ≤1 / 2, -0.41≤D br <0, elastic modulus E; h of the airbag support arm 21a , h 1a , the thickness ratio of the parabolic segment of the airbag support arm is β a =h 1a / h 21a and the length L of the parabola segment pa , elastic modulus E, b calculated in S21 21a and b 1a , k calculated in step S11 Fa , the flexibility R of the parabolic segment of the non-standard parabolic airbag support arm with chamfered cross section dpa Perform the calculation, namely:

[0051]

[0052] Where: The flexibility coefficient of the parabolic segment of the airbag support arm with a chamfered cross section;

[0053] S222: rectangular cross section, i.e.: k r =0

[0054] According to the guide arm width B, the cross section is rectangular, that is: k r =0, elastic modulus E; h of the airbag support arm 21a , h 1a , β a =h1a / h 21a , L pa , elastic modulus E, k calculated in step S11 Fa , the flexibility R of the parabolic segment of the airbag support arm with a right angle transverse section dpa Perform the calculation, namely:

[0055]

[0056] Where: G Rdpa_ZJ is the flexibility coefficient of the parabolic segment of the airbag support arm with a right-angle cross section,

[0057]

[0058] S23: Flexibility R of the vertical arm section of the airbag support arm dz2a Calculation:

[0059] According to the h of the airbag support arm 2a , L 21a , L pa , height of vertical arm h z2 , elastic modulus E, k calculated in step S11 Fa , b calculated in S21 za , the flexibility of the vertical arm section of the airbag support arm is R dz2a Perform the calculation, namely:

[0060]

[0061] S24: The flexibility R of the straight section at the root of the airbag support arm and the straight section outside the vertical arm d22a and R d21a Calculation:

[0062] According to the clamping distance U of the riding bolt, the L of the airbag support arm a , h 2a , h 21a , L z2 , L 21a ,L pa , elastic modulus E, equivalent width b calculated in S21 2a and b 21a , k calculated in step S11 Fa , the flexibility R of the straight section at the root of the airbag support arm d22a , the flexibility R of the straight section outside the drop arm d21a Perform the calculation, namely:

[0063]

[0064] S25: Clamping flexibility R of non-standard parabolic airbag support arm da Calculation:

[0065] According to the R calculated in S22 dpa , R calculated in S23 dz2a , R calculated in S24 d22a , and R d21a , the clamping flexibility R of the non-standard parabolic airbag support arm da Perform the calculation, namely:

[0066] R da =R d22a +R dz2a +R d21a +R dpa ;

[0067] S3: Clamping stiffness K of non-standard parabolic guide arm assembly z Verification calculation:

[0068] According to the R calculated in S1 db , R calculated in S2 da , the clamping stiffness K of the parabolic guide arm assembly z Perform the check calculation, namely:

[0069]

[0070] S4: Composite stiffness K of non-standard parabolic guide arm air suspension system C Verification calculation:

[0071] According to the front guide arm length L b , the length of the airbag support arm L a , airbag stiffness K under rated load A , K calculated in S3 z , the composite stiffness K of the non-standard air suspension system C Perform the check calculation, namely:

[0072]

[0073] S5: Verification calculation of the offset frequency f0 of the non-standard parabolic guide arm air suspension system:

[0074] According to the single wheel rated sprung mass m2, K calculated in S4 C , the non-standard parabolic guide arm air suspension offset frequency f0 is checked and calculated, namely:

[0075]

[0076] S6: Verification calculation of the damping ratio ξ of the non-standard parabolic guide arm air suspension system:

[0077] According to the damping coefficient C of the shock absorber d , shock absorber installation angle α, single wheel rated sprung mass m2, K calculated in S4 C , the damping ratio ξ of the non-standard parabolic guide arm air suspension system is checked and calculated, namely:

[0078]

[0079] S7: Stress strength verification calculation of non-standard parabolic guide arm assembly:

[0080] S11: Calculation of the end loads of each non-standard parabolic front guide arm and airbag support arm:

[0081] According to the single wheel rated sprung mass m2, the number of front guide arms n, the k calculated in step S11 Fb and k Fa , R calculated in S16 dbi and K calculated in S17 b , for each non-standard front end guide arm end load F bi and the end load F of the airbag support arm a Calculate, i=1,2,…,n, that is:

[0082]

[0083] F a =k Fa m29.8;

[0084] When the number of front guide arms n = 1, F b1 =k Fb m29.8;

[0085] S12: Calculation and verification of the maximum stress at the root of each non-standard parabolic front guide arm and airbag support arm

[0086] According to the clamping distance U of the riding bolt, the number n of the front guide arm, and the L of the front guide arm b , h 2i , L of the airbag support arm a , h 2a , F calculated in S11 bi , F a , b calculated in step S12 2i , b calculated in step S21 2a , the maximum stress σ at the root of each non-standard parabolic front guide arm maxbi and the maximum stress at the root of the airbag support arm σ maxa Perform the calculation, namely:

[0087]

[0088] The calculated σ maxbi and σ maxa Compared with the allowable stress [σ], if σ maxbi and σ maxa If both are less than [σ], the stress intensity requirement is met; otherwise, the stress intensity requirement is not met.

[0089] The beneficial effects of the present invention are as follows: the present invention can calibrate the composite stiffness, suspension frequency deviation, suspension system damping ratio and stress intensity of the non-standard parabolic guide arm air suspension system according to the structural parameters, rated load and allowable stress of the non-standard parabolic guide arm assembly, the stiffness of the airbag under the rated load, the shock absorber damping coefficient and the installation angle; through prototype vehicle testing, it can be ensured that the key parameters of the non-standard parabolic guide arm air suspension system meet the design requirements, thereby improving the design level of the trailer air suspension system and the vehicle's driving smoothness and safety; at the same time, the design and testing costs are reduced and the product development speed is accelerated. BRIEF DESCRIPTION OF THE DRAWINGS

[0090] Figure 1 This is a calibration flow chart for a non-standard parabolic guiding arm air suspension system;

[0091] Figure 2 It is the structural diagram and mechanical model of the non-standard parabolic guide arm;

[0092] Figure 3 Schematic diagrams of the two ends of three different types of cross sections of non-standard parabolic guide arm assemblies.

[0093] In the figure: 1. Front guide arm; 2. Airbag support arm. DETAILED DESCRIPTION

[0094] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention.

[0095] The present invention is further described in detail below by way of examples.

[0096] Example 1: Figures 1 to 3 As shown in the figure, the width of the guide arm assembly of a trailer air suspension system is B = 104mm, the two ends of the cross section are chamfered, and the cross section chamfer radius thickness ratio k r =0.2, elastic modulus E = 206GPa, saddle bolt clamping distance U = 180mm. The guide arm assembly is composed of the front guide arm and the airbag support arm. The number of front guide arms n = 2, the length of each front guide arm L b=547mm, each front end guide arm consists of a straight root section, a parabola section and an end straight section. The length of the straight root section of each front end guide arm is L2 = 200mm, and the length from the root of the parabola section to the end point of the front end guide arm is L 2p =L b -L2=347mm; the thickness of the straight section at the root of each front guide arm h 21 =h 22 = 28mm, the thickness of the straight section at the end of each front guide arm h 11 =20mm,h 12 =15mm, the parabolic segment thickness ratio of each front guide arm is β i =h 1i / h 2i , that is: β1 = 0.7143, β2 = 0.5357; the length L of the straight section at the end of each front guide arm 11 =75mm, L 12 =50mm; the length of the parabola segment of each front guide arm is L p1 =L 2p -L 11 =272mm, L p2 =L 2p -L 12 =297mm. Due to L 1i ≠β i 2 L 2p Therefore, the guide arm of the front section of each piece is a non-standard parabola; the number of airbag support arms is n a =1, the distance from the center of the saddle bolt clamping distance to the airbag installation center is the length of the airbag support arm L a =380mm, the airbag support arm consists of a straight section at the root, a vertical arm and a parabola section; the length of the straight section at the root of the airbag support arm is L 22a =135mm, the length of the straight section outside the vertical arm L 21a =50mm, thickness of the straight section at the root of the airbag support arm h 2a =38mm, the thickness of the airbag at the center of the parabola segment, that is, the end thickness of the parabola segment h 1a =25mm, the thickness ratio of the parabola segment of the airbag support arm is β a =h 1a / h 2a =0.6579, vertical arm height h z2 =110mm. The allowable stress under rated load [σ N ]=450MPa. Airbag stiffness K under rated load A =178.0N / mm. The rated sprung mass of a single wheel is m2 = 6000kg, the installation angle is 30°, and the shock absorber damping coefficient is C d=16110N / ms -1 Based on the structural parameters, rated load and allowable stress of the non-standard parabolic guide arm assembly, the stiffness of the airbag under the rated load, the damping coefficient of the shock absorber and its installation angle, the composite stiffness, suspension offset frequency, suspension system damping ratio and stress intensity of the non-standard parabolic guide arm air suspension system are checked.

[0097] The present invention provides a calibration method for a non-standard parabolic guide arm air suspension system, the calibration process of which is as follows: Figure 1 The specific verification steps are as follows:

[0098] S1: Clamping flexibility R of the front guide arm of the non-standard parabolic guide arm assembly db Calculation:

[0099] S11: Load distribution ratio coefficient k of front guide arm and airbag support arm Fb and k Fa Calculation:

[0100] According to the front end guide arm length L of the guide arm assembly b =547mm, length of airbag support arm L a =380mm, load distribution coefficient k for the front guide arm and airbag support arm Fb and k Fa Calculate separately,

[0101]

[0102] S12: Equivalent width b of the straight section at the root and end of each front guide arm 2i and b 1i Calculation:

[0103] According to the guide arm width B = 104mm, the chamfer radius thickness ratio k at both ends of the cross section r =0.2, equivalent width reduction factor The number of front guide arms is n = 2, and the h of each front guide arm is 21 =h 22 =28mm,h 11 =20mm,h 12 =15mm, the equivalent width b of the straight section at the root of each front guide arm 2i and the equivalent width b of the straight section at the end 1i Calculate, i=1,2,…n, that is

[0104] b 2i =B+h 2i D br ;

[0105] b1i =B+h 1i D br ;

[0106] That is, b 21 =b 22 =101.6mm; b 11 =102.3mm, b 12 =102.7mm;

[0107] S13: Parabola segment coordinate offset x of each non-standard parabola front guide arm 0i Calculation:

[0108] According to the number of front guide arms n = 2, the L of each front guide arm 2p =347mm,h 21 =h 22 =28.0mm,h 11 =20mm,h 12 =15mm, β1=0.7143, β2=0.5357, L 11 =75mm, L 12 =50mm, for each piece of non-standard parabola parabola segment coordinate offset x 0i Calculate, i=1,…,n, that is

[0109]

[0110] S14: The flexibility of the straight section of each front end guide arm R d1i Calculation:

[0111] According to the number of front guide arms n = 2, the h of each front guide arm 11 =20mm,h 12 =15mm; L 11 =75mm and L 12 =50mm, elastic modulus E = 206GPa, k calculated in S11 Fb =0.41, b calculated in S12 11 =102.3mm, b 12 =102.7mm, the flexibility of the straight section of each front end guide arm R d1i Calculate, i=1,2,…n, that is

[0112]

[0113] S15: Clamping flexibility R of the straight section at the root of each front guide arm d2i Calculation:

[0114] According to the length L of the front guide armb =547mm, the number of front guide arms n = 2, the h of each front guide arm 21 =h 22 =28.0mm, L 2p =347mm, elastic modulus E = 206GPa, saddle bolt clamping distance U = 180mm, k calculated in S11 Fb =0.41, b calculated in S12 21 =b 22 =101.6mm, the clamping flexibility R of the straight section at the root of each front guide arm d2i Calculate, i=1,2,…n, that is

[0115]

[0116] Among them, R d21 =R d22 =1.24×10 -4 mm / N;

[0117] S16: Parabolic segment flexibility R of each non-standard parabolic front guide arm dpi Calculation:

[0118] According to the guide arm width B = 104mm, the chamfer radius thickness ratio k at both ends of the cross section r =0.2, equivalent width reduction factor D br =-0.086, elastic modulus E = 206GPa; the number of front guide arms n = 2, the L of each front guide arm 2p =347mm, L 11 =75mm, L 12 =50mm;h 21 =h 22 =28.0mm,h 11 =20mm,h 12 =15mm, β1=h 11 / h 21 =0.7143, β2=h 12 / h 22 =0.5357, k calculated in S11 Fb =0.41, b calculated in S12 21 =b 22 =101.6mm, b 11 =102.3mm, b 12 =102.7mm; x calculated in S13 01 =208.3mm, x 02 = 69.5mm, the length L from the root of the parabola segment of each front guide arm to the coordinate origin 2pTi=L 2p +x 0i , that is: L 2pT1 =555.33mm, L 2pT2 =416.54mm, the parabolic segment flexibility R of each non-standard parabolic front end guide arm with chamfered cross section dpi Calculate, i=1,2,…,n, that is:

[0119]

[0120]

[0121] Where: G Rdpi is the flexibility coefficient of the non-standard parabolic segment of the i-th front end guide arm with chamfered cross section, Among them, G Rdp1 =0.935, G Rdp2 =0.851;

[0122] S17: Clamping flexibility R of each non-standard parabolic front guide arm dbi Calculation:

[0123] According to the number of the front guide arm n = 2, the R calculated in S14 is d11 =1.6829×10 -6 mm / N, R d12 =1.177×10 -6 mm / N; R calculated in S15 d21 =R d22 =1.24×10 -4 mm / N, R calculated in S16 dp1 =8.0697×10 -5 mm / N, R dp2 =9.5623×10 -5 mm / N, clamping flexibility R for each non-standard parabolic front guide arm dbi Calculate, i=1,2,..,n, that is:

[0124] R dbi =R d2i +R d1i +R dpi , i=1,2,..,n;

[0125] Among them, R db1 =2.0638×10 -4 mm / N, R db2 =2.2080×10 -4 mm / N;

[0126] S18: Clamping stiffness K of non-standard parabolic front guide arm b and clamping flexibility R db Calculation:

[0127] According to the number of the front guide arm n = 2, the R calculated in S17 db1 =2.0638×10 -4 mm / N, R db2 =2.2080×10 -4 mm / N, clamping stiffness K for non-standard parabolic front guide arm b and clamping flexibility R db Perform the calculation, namely:

[0128]

[0129] S2: Clamping flexibility R of the airbag support arm of the non-standard parabolic end guide arm assembly da Calculation:

[0130] S21: Calculation of the equivalent width of each section of the airbag support arm:

[0131] According to the width of the guide arm B = 104mm, the chamfer radius thickness ratio k at both ends of the cross section is r =0.2, equivalent width reduction factor D br =-0.086; h of the airbag support arm 2a =38mm, L z2 =h 2a =38mm,h 21a =h 2a =38mm,h 1a =25mm, equivalent width b of the straight section at the root of the airbag support arm 2a , the equivalent width b at the vertical arm za , the equivalent width b of the straight section outside the drop arm 21a , the equivalent width b at the end of the parabola segment 1a Perform the calculation, namely:

[0132] b 2a =B+h 2a D br =100.7mm, b za =B+L z2 D br =100.7mm,

[0133] b 21a =B+h 21a D br =100.7mm, b 1a =B+h 1a D br=101.8mm;

[0134] S22: Flexibility R of the parabolic segment of the non-standard parabolic airbag support arm dpa Calculation:

[0135] According to the guide arm width B = 104mm, the chamfer radius thickness ratio k at both ends of the cross section r =0.2, equivalent width reduction factor D br =-0.086, elastic modulus E = 206GPa; h of the airbag support arm 2a =38mm,h 21a =h 2a =38mm,h 1a =25mm, L pa =157mm,β a =h 1a / h 21a =0.658, b calculated in S21 21a =100.7mm and b 1a =101.8 mm, k calculated in step S11 Fa =0.59, the flexibility R of the parabolic segment of the non-standard parabolic airbag support arm dpa Perform the calculation, namely:

[0136]

[0137] Where: G Rdpa is the flexibility coefficient of the parabolic segment of the non-standard parabolic airbag support arm with chamfered cross section,

[0138] S23: Flexibility R of the vertical arm section of the airbag support arm dz2a Calculation:

[0139] According to the h of the airbag support arm 2a =38mm, L 21a =50mm, L pa =157mm, height of vertical arm h z2 =110mm, elastic modulus E = 206GPa, b calculated in step I za =100.7mm, k calculated in S1 Fa =0.59, the flexibility of the vertical arm section of the airbag support arm R dz2a Perform the calculation, namely:

[0140]

[0141] S24: The flexibility R of the straight section at the root of the airbag support arm and the straight section outside the vertical arm d22a and R d21aCalculation:

[0142] According to the L of the airbag support arm a =380mm, L 21a =50mm, L pa =157mm,h 2a =38mm,h 21a =h 2a =38mm, length of the vertical arm L z2 =h 2a =38mm, elastic modulus E = 206GPa, saddle bolt clamping distance U = 180mm, equivalent width b calculated in S21 2a =100.7mm, b 21a =100.7 mm, k calculated in step S11 Fa =0.59, the flexibility R of the straight section at the root of the airbag support arm d22a , the flexibility R of the straight section outside the drop arm d21a Perform the calculation, namely:

[0143]

[0144]

[0145] S25: Clamping flexibility R of non-standard parabolic airbag support arm da Calculation:

[0146] According to the R calculated in S22 dpa =6.1584×10 -6 mm / N, R calculated in S23 dz2a =1.7292×10 -5 mm / N, R calculated in S24 d22a =2.7991×10 -5 mm / N, R d21a =6.1142×10 -6 mm / N, clamping flexibility R for non-standard parabolic airbag support arms da Perform the calculation, namely:

[0147] R da =R d22a +R dz2a +R d21a +R dpa =5.7555×10 -5 mm / N.

[0148] S3: Clamping stiffness K of non-standard parabolic guide arm assembly z Verification calculation:

[0149] According to the R calculated in S1 db =1.0661×10 -4 mm / N, R calculated in S2 da =5.7555×10 - 5 mm / N, clamping stiffness K for non-standard parabolic guide arm assembly z Perform the check calculation, namely:

[0150]

[0151] S4: Composite stiffness K of non-standard parabolic guide arm air suspension system C Verification calculation:

[0152] According to the length L of the front guide arm b =547mm, length of airbag support arm L a =380mm, airbag stiffness K under rated load A =178.0N / mm, K calculated in S3 z =6089.0N / mm, composite stiffness K for non-standard parabolic guide arm air suspension system C Perform the check calculation, namely:

[0153]

[0154] S5: Verification calculation of the offset frequency f0 of the non-standard parabolic guide arm air suspension system:

[0155] According to the rated sprung mass of a single wheel m2 = 6000 kg, K calculated in S4 C =287.42N / mm, and the non-standard parabolic guide arm air suspension offset frequency f0 is checked and calculated, namely:

[0156]

[0157] S6: Verification calculation of the damping ratio ξ of the non-standard parabolic guide arm air suspension system:

[0158] According to the damping coefficient C of the shock absorber d =16110N / ms -1 , shock absorber installation angle α=30°, single wheel rated sprung mass m2=6000kg, K calculated in S4 C =287.42N / mm, and the damping ratio ξ of the non-standard parabolic guide arm air suspension system is verified and calculated, namely:

[0159]

[0160] S7: Stress strength verification calculation of non-standard parabolic guide arm assembly:

[0161] S71: Calculation of the end loads of each non-standard parabolic front guide arm and airbag support arm:

[0162] According to the rated sprung mass of a single wheel m2 = 6000 kg, the number of front guide arms n = 2, the k calculated by S11 Fb =0.41 and k Fa =0.59, R calculated in S16 db1 =2.0638×10 -4 mm / N, R db2 =2.2080×10 -4 mm / N, K calculated in S17 b =9374.3N / mm, the end load F of each non-standard front guide arm bi and the end load F of the airbag support arm a Calculate, i=1,2,..,n

[0163]

[0164] F a =k Fa m29.8=34692N;

[0165] S72: Calculation and verification of the maximum stress at the root of each non-standard parabolic front guide arm and airbag support arm

[0166] According to the number of the front guide arm n = 2, the L of the front guide arm b 547mm, h 21 =h 22 =28mm, L of airbag support arm a =380mm,h 2a =38mm, the saddle bolt clamping distance U = 180mm, and the b calculated in step S72 2i , that is: b 21 =b 22 =101.6mm, F calculated in S11 b1 =12460N,F b2 =11647N;F a =34692N, b calculated in step S21 2a =100.7mm, the maximum stress σ at the root of each non-standard parabolic front guide arm maxbi and the maximum stress at the root of the airbag support arm σ maxa Calculate, i=1,2,..,n, that is:

[0167]

[0168]

[0169] It can be seen that the calculated σ maxb1 , σ maxb2 and σ maxa Both are less than [σ]=450MPa, meeting the stress strength requirements.

[0170] Example 2: Figure 3 As shown, this example has the exception of the arc-shaped ends of the cross section, i.e., k r = 0.5, the number of front guide arm pieces n = 1 and the thickness and the length of the end straight section, the other structural parameters, elastic modulus, allowable stress, load and airbag stiffness under rated load, shock absorber damping coefficient and installation angle are the same as those of the first embodiment. 21 =43mm,h 11 =20mm, L 11 =50mm; thickness of the straight section at the root of the airbag support arm h 2a =41mm, h of airbag support arm 2a =41mm,h 1a =25mm, L pa = 154mm. Based on the width, installation dimensions, front-end guide arm length, airbag support arm length, rated load, airbag stiffness, and allowable stress of the guide arm assembly, the front-end guide arm and airbag support arm, the initial angle of the height valve stabilizer bar, the airbag diameter, and the shock absorber velocity characteristics of the non-standard parabolic guide arm air suspension system are verified.

[0171] The calibration method for a non-standard parabolic guiding arm air suspension system provided in this embodiment of the present invention has the same calibration steps as those in the first embodiment. The specific calibration steps are as follows:

[0172] S1: Clamping flexibility R of the front guide arm of the non-standard parabolic guide arm assembly db Calculation:

[0173] S11: Load distribution ratio coefficient k of front guide arm and airbag support arm Fb and k Fa Calculation:

[0174] Since the structure of the guide arm assembly is exactly the same as that of the first embodiment, the load distribution ratio coefficient k of the front guide arm and the airbag support arm is Fb and k Fa It is also exactly the same as that of the first embodiment, that is:

[0175]

[0176] S12: Equivalent width b of the straight section at the root and end of each front guide arm 2i and b 1i Calculation:

[0177] According to the width of the guide arm B = 104mm, the two ends of the cross section are arc-shaped, that is, the chamfer radius thickness ratio k r =0.5, equivalent width reduction factor D br =-0.411; the number of front guide arm pieces n = 1, the h of the front guide arm 21 =43mm,h 11 = 20mm, the equivalent width b of the straight section at the root of each front guide arm 2i and the equivalent width b of the straight section at the end 1i Calculate, i=1,…,n, that is:

[0178] b 21 =B+D br h 21 =86.3mm, b 11 =B+D br h 11 =95.8mm;

[0179] S13: Parabola segment coordinate translation x of each non-standard parabola front guide arm 0i Calculation:

[0180] According to the number of front guide arm pieces n=1, the L of the front guide arm 2p =347mm, L 11 =50mm,h 21 =43mm,h 11 =20mm, β1=h 11 / h 21 =0.4651, the parabola segment coordinate offset x for the non-standard parabola front guide arm 0i Calculate, i=1,…,n, that is

[0181]

[0182] S14: Flexibility R of the straight section at the end of each front guide arm d1i Calculation:

[0183] According to the number of front guide arm pieces n = 1, the h of the front guide arm 11 =20mm, L 11 =50.0mm, elastic modulus E = 206GPa, k calculated in S11 Fb =0.41, b calculated in S12 1i , that is: b 11=95.8mm, the flexibility of the straight section of the front guide arm end R d1i Calculate, i=1,…,n, that is:

[0184]

[0185] S15: Clamping flexibility R of the straight section at the root of each front guide arm d2i Calculation:

[0186] According to the number of front guide arm pieces n = 1, the h of the front guide arm 21 =43.0mm, L b =547mm, L 2p =347mm, elastic modulus E = 206GPa, saddle bolt clamping distance U = 180mm, k calculated in S11 Fb =0.41, b calculated in S12 21 =86.3mm, clamping flexibility R of the straight section at the root of the front guide arm d2i Perform the calculation, namely:

[0187]

[0188] S16: Parabolic segment flexibility R of each non-standard parabolic front guide arm dpi Calculation:

[0189] According to the guide arm width B = 104mm, the cross section is arc-shaped at both ends, k r =1 / 2, D br =-0.411, elastic modulus E = 206GPa; the number of front guide arm pieces n = 1, the L of the front guide arm 2p =347mm, L 11 =50mm;h 21 =43.0mm,h 11 =20mm, β1=h 11 / h 21 =0.4651, k calculated in S11 Fb =0.41, b calculated in S12 21 =86.3mm, b 11 =95.8mm; x calculated in S13 01 =31.98mm, and the length L from the root of the parabola segment to the origin of the coordinate system 2pT1 =L 2p +x 01 =378.98mm, parabolic segment flexibility R for non-standard parabolic front guide arm dpi Calculate, i=1,2,…,n, that is:

[0190]

[0191] Where: G Rdp1 is the flexibility coefficient of the non-standard parabolic segment of the first front guide arm with chamfered cross section,

[0192] S17: Clamping flexibility R of each non-standard parabolic front guide arm dbi Calculation:

[0193] According to the number of the front guide arm n = 1, the R calculated in S14 d11 =5.3248×10 -7 mm / N; R calculated in S15 d21 =4.4267×10 -5 mm / N, R calculated in S16 dp1 =3.4327×10 -5 mm / N, clamping flexibility R for each non-standard parabolic front guide arm dbi Calculate, i=1,…,n, that is:

[0194] R db1 =R d21 +R d11 +R dp1 =7.5150×10 -5 mm / N;

[0195] S18: Clamping stiffness K of non-standard parabolic front guide arm b and flexibility R db Calculation:

[0196] According to the number of the front guide arm n = 1, the R calculated in S17 dbi , that is: R db1 =7.5150×10 -5 mm / N, clamping stiffness K of the front guide arm b and clamping flexibility R db Perform the calculation, namely:

[0197]

[0198] S2: Clamping flexibility R of the airbag support arm of the non-standard parabolic end guide arm assembly da Calculation:

[0199] S21: Calculation of the equivalent width of each section of the airbag support arm:

[0200] According to the width of the guide arm B = 104mm, the cross section is arc-shaped at both ends, D br =-0.411, h of the airbag support arm2a =41mm, L z2 =h 2a =41mm,h 21a =h 2a =41mm,h 1a =25mm, equivalent width b of the straight section at the root of the airbag support arm 2a , the equivalent width b at the vertical arm za , the equivalent width b of the straight section outside the drop arm 21a , the equivalent width b at the end of the parabola segment 1a Perform the calculation, namely:

[0201] b 2a =B+D br h 2a =87.2mm; b za =B+D br L z2 =87.2mm;

[0202] b 21a =B+D br h 21a =87.2mm; b 1a =B+D br h 1a =93.7mm;

[0203] S22: Flexibility R of the parabolic segment of the airbag support arm dpa Calculation:

[0204] According to the guide arm width B = 104mm, the cross section is arc-shaped at both ends, D br =-0.411, elastic modulus E = 206GPa; h of the airbag support arm 21a =h 2a =41mm,h 1a =25mm, L pa =154mm,β a =h 1a / h 21a =0.6097, b calculated in S21 21a =87.2mm, b 1a =93.7 mm, k calculated in step S11 Fa =0.59, the flexibility R of the parabolic segment of the non-standard parabolic airbag support arm dpa Perform the calculation, namely:

[0205]

[0206] Where: G Rdpa is the flexibility coefficient of the parabolic segment of the airbag support arm with a chamfered cross section,

[0207] S23: Flexibility R of the vertical arm section of the airbag support arm dz2a Calculation:

[0208] According to the h of the airbag support arm 2a =41mm, L 21a =50mm, L pa =154mm, height of vertical arm h z2 =110mm, elastic modulus E = 206GPa, b calculated in S21 za =87.2 mm, k calculated in step S11 Fa =0.59, the flexibility of the vertical arm section of the airbag support arm R dz2a Perform the calculation, namely:

[0209]

[0210] S24: The flexibility R of the straight section at the root of the airbag support arm and the straight section outside the vertical arm d22a and R d21a Calculation:

[0211] According to the saddle bolt clamping distance U = 180mm, the length of the airbag support arm L a =380mm, L 21a =50mm, L pa =154mm,h 2a =h 21a =41mm, elastic modulus E=206GPa, equivalent width b calculated in S21 2a =87.2mm, b 21a =87.2 mm, k calculated in step S11 Fa =0.59, the flexibility of the straight section at the root of the airbag support arm R d22a , the flexibility R of the straight section outside the drop arm d21a Perform the calculation, namely:

[0212]

[0213]

[0214] S25: Non-standard parabolic airbag support arm clamping flexibility R da Calculation:

[0215] According to the R calculated in S22 dpa =5.4672×10 -6 mm / N, R calculated in S23 dz2a =1.5452×10 -5mm / N, R calculated in S24 d22a =2.5758×10 -5 mm / N, R d21a =5.4436×10 -6 mm / N, airbag support arm clamping flexibility R da Perform the calculation, namely:

[0216] R da =R d22a +R dz2a +R d21a +R dpa =5.2122×10 -5 mm / N;

[0217] S3: Clamping stiffness K of non-standard parabolic guide arm assembly z Verification calculation:

[0218] According to the R calculated in S1 db =7.5150×10 -5 mm / N, R calculated in S2 da =5.2122×10 - 5 mm / N, clamping stiffness K of guide arm assembly z Perform the check calculation, namely:

[0219]

[0220] S4: Composite stiffness K of non-standard parabolic guide arm air suspension system C Verification calculation:

[0221] According to the front guide arm length L b =547mm, length of airbag support arm L a =380mm, airbag stiffness K under rated load A =178.0N / mm, K calculated in S3 z =7857.1N / mm, composite stiffness K of air suspension system C Perform the calculation, namely:

[0222]

[0223] S5: Verification calculation of the offset frequency f0 of the non-standard parabolic guide arm air suspension system:

[0224] According to the rated sprung mass of a single wheel m2 = 6000 kg, K calculated in S4 C =290.50N / mm, and the non-standard parabolic guide arm air suspension offset frequency f0 is checked and calculated, namely:

[0225]

[0226] S6: Verification calculation of the damping ratio ξ of the non-standard parabolic guide arm air suspension system:

[0227] According to the damping coefficient C of the shock absorber d =16110N / ms -1 , shock absorber installation angle α=30°, single wheel rated sprung mass m2=6000kg, K calculated in S4 C =290.50N / mm, and the damping ratio ξ of the non-standard parabolic guide arm air suspension system is verified and calculated, namely:

[0228]

[0229] S7: Stress strength verification calculation of non-standard parabolic guide arm assembly:

[0230] S71: Calculation of the end loads of each non-standard parabolic front guide arm and airbag support arm:

[0231] According to the rated sprung mass of a single wheel m2 = 6000 kg, the number of front guide arms n = 1, the k calculated by S11 is Fb =0.59 and k Fa =0.41, the end load F of each non-standard front guide arm bi and the end load F of the airbag support arm a Perform the calculation, namely:

[0232] F b1 =k Fb m29.8=24108N;

[0233] F a =k Fa m29.8=34692N;

[0234] S72: Calculation and verification of the maximum stress at the root of each non-standard parabolic front guide arm and airbag support arm

[0235] According to the number of the front guide arm n = 1, the L of the front guide arm b =547mm,h 21 =43mm, L of airbag support arm a =380mm,h 2a =41mm, saddle bolt clamping distance U = 180mm, F calculated in S71 b1 =24108N,F a =34692N, b calculated in step S1221 =86.3 mm, b calculated in step S21 2a =87.2mm, the maximum stress σ at the root of each non-standard parabolic front guide arm maxbi and the maximum stress at the root of the airbag support arm σ maxa Perform the calculation, namely:

[0236]

[0237]

[0238] It can be seen that σ maxb1 and σ maxa are all less than [σ], therefore, the stress intensity requirements are met.

[0239] Example 3: This example has a cross section with two ends that are right angles, namely k r = 0, except for the thickness and length of the end straight section, other structural parameters, elastic modulus, allowable stress, load and airbag stiffness under rated load are exactly the same as those of the second embodiment. 21 =40mm,h 11 =20mm, L 11 =75mm; thickness of the straight section at the root of the airbag support arm h 2a =41mm, h of airbag support arm 2a =38mm,h 1a =25mm, L pa = 157mm. Based on the width, installation dimensions, front-end guide arm length, airbag support arm length, rated load, airbag stiffness, and allowable stress of the guide arm assembly, the front-end guide arm and airbag support arm, the initial angle of the height valve stabilizer bar, the airbag diameter, and the shock absorber velocity characteristics of the non-standard parabolic guide arm air suspension system are verified.

[0240] The calibration method for a non-standard parabolic guiding arm air suspension system provided in this embodiment of the present invention has the same calibration steps as those in the second embodiment. The specific calibration steps are as follows:

[0241] S1: Clamping flexibility R of the front guide arm of the non-standard parabolic guide arm assembly db Calculation:

[0242] S11: Load distribution ratio coefficient k of front guide arm and airbag support arm Fb and k Fa Calculation:

[0243] Since the structure is exactly the same as that of the second embodiment, the load distribution ratio coefficient k of the front guide arm and the airbag support arm is Fb and kFa It is also exactly the same as that of the second embodiment, that is:

[0244]

[0245] S12: Equivalent width b of the straight section at the root and end of each front guide arm 2i and b 1i Calculation:

[0246] Since the two ends of the cross section are right angles, that is, k r =0, equivalent width reduction coefficient D br = 0, therefore, the equivalent width b of the straight section at the root and the straight section at the end of the guide arm at the front end of the blade 2i and b 1i are equal to the guide arm width B, that is:

[0247] b 21 =B=104mm, b 11 =B=104mm.

[0248] S13: Parabola segment coordinate offset x of each non-standard parabola front guide arm 0i Calculation:

[0249] According to the number of front guide arm pieces n = 1, the h of the front guide arm 21 =40.0mm,h 11 =20mm, L 2p =347mm, L 11 =75mm, β1=h 11 / h 21 = 0.5, for each non-standard parabola segment coordinate offset x 0i Calculate, i=1,…,n, that is:

[0250]

[0251] S14: The flexibility of the straight section of each front end guide arm R d1i Calculation:

[0252] According to the number of front guide arm pieces n = 1, elastic modulus E = 206GPa; the h of the front guide arm 11 =20mm, L 11 =75mm, k calculated in S11 Fb =0.41, b calculated in S12 11 =104mm, for the flexibility R of the straight section at the end of each non-standard parabolic front guide arm d1i Calculate, i=1,…,n, that is:

[0253]

[0254] S15: Clamping flexibility R of the straight section at the root of each front guide arm d2i Calculation:

[0255] According to the saddle bolt clamping distance U = 180mm, the number of front guide arm pieces n = 1, the length of the front guide arm L b =547mm, L 2p =347mm,h 21 =40mm, elastic modulus E = 206GPa, k calculated in S11 Fb =0.41, b calculated in S12 21 =104mm, clamping flexibility R of the straight section at the root of the front guide arm d2i Perform the calculation, namely:

[0256]

[0257] S16: Parabolic segment flexibility R of each non-standard parabolic front guide arm dpi Calculation:

[0258] According to the guide arm width B = 104mm, the cross section has two right angles, namely k r = 0, elastic modulus E = 206GPa; the number of front guide arm pieces n = 1, the L of the front guide arm 2p =347mm, L 11 =75mm;h 21 =40mm,h 11 =20mm, β1=h 11 / h 21 =0.5, k calculated in S11 Fb =0.41, calculated in S13: obtained x 01 =15.7mm, L 2pT1 =L 2p +x 01 =362.67mm, the parabolic segment flexibility R of the front guide arm with right angles at both ends of the cross section dpi Calculate, i=1,…,n, that is:

[0259]

[0260] Where: G Rdp_ZJ1 is the flexibility coefficient of the parabolic segment of the front guide arm with right angles at both ends of the cross section,

[0261] S17: Clamping flexibility R of each non-standard parabolic front guide arm dbi Calculation:

[0262] According to the number of the front guide arm n = 1, the R calculated in S14 d11 =1.6545×10 -6 mm / N; R calculated in S15 d21 =4.1533×10 -5 mm / N, R calculated in S16 dp1 =3.5135×10 -5 mm / N, clamping flexibility R for each non-standard parabolic front guide arm dbi Calculate, i=1,…,n, that is:

[0263] R db1 =R d21 +R d11 +R dp1 =7.8339×10 -5 mm / N;

[0264] S18: Clamping stiffness K of non-standard parabolic front guide arm b and clamping flexibility R db Calculation:

[0265] According to the number of the front guide arm n = 1, the R calculated in S15 dbi , that is: R db1 =7.8339×10 -5 mm / N, clamping stiffness K of the front guide arm b and clamping flexibility R db Calculate, i=1,…,n, that is:

[0266]

[0267] S2: Clamping flexibility R of the airbag support arm of the non-standard parabolic end guide arm assembly da Calculation:

[0268] S21: Calculation of the equivalent width of each section of the airbag support arm:

[0269] According to the cross section, both ends are right angles, that is, k r =0, therefore, the equivalent width of each section of the airbag support arm is equal to the guide arm width, that is:

[0270] b 2a =B=104mm; b za =B=104mm;

[0271] b 21a =B=104mm; b 1a =B=104mm;

[0272] S22: Flexibility R of the parabolic segment of the airbag support arm dpa Calculation:

[0273] According to the guide arm width B = 104mm, the cross section has two right angles, namely k r =0, elastic modulus E = 206GPa; airbag support arm h 21a =h 2a =38mm,h 1a =25mm, L pa =157mm,β a =h 1a / h 21a =0.6579, according to the elastic modulus E = 206 GPa, the k calculated in step S11 Fa = 0.59, the flexibility R of the parabolic segment of the airbag support arm with right angles at both ends of the cross section dpa Perform the calculation, namely:

[0274]

[0275] Where: G Rdpa_ZJ is the flexibility coefficient of the parabolic segment of the airbag support arm with right angles at both ends of the cross section,

[0276] S23: Flexibility R of the vertical arm section of the airbag support arm dz2a Calculation:

[0277] According to the h of the airbag support arm z2 =110mm,h 2a =38mm, L 21a =50mm, L pa =157mm, elastic modulus E = 206GPa, b calculated in S21 za =B=104mm, k calculated in step S11 Fa =0.59, the flexibility of the vertical arm section of the airbag support arm R dz2a Perform the calculation, namely:

[0278]

[0279] S24: The flexibility R of the straight section at the root of the airbag support arm and the straight section outside the vertical arm d22a and R d21a Calculation:

[0280] According to the bolt clamping distance U=180mm, the h of the airbag support arm 2a =38mm,h 21a =h 2a =38mm, L a =380mm, L21a =50mm, L z2 =h 2a =38mm, L pa =157mm, elastic modulus E = 206GPa, equivalent width b calculated in S21 2a =b 21a =B=104mm, k calculated in step S11 Fa =0.59, the flexibility of the straight section at the root of the airbag support arm R d22a , the flexibility R of the straight section outside the drop arm d21a Perform the calculation, namely:

[0281]

[0282]

[0283] S25: Clamping flexibility R of non-standard parabolic airbag support arm da Calculation:

[0284] According to the R calculated in S22 dpa =5.9823×10 -6 mm / N, R calculated in S23 dz2a =1.6747×10 -5 mm / N, R calculated in S24 d22a =2.7118×10 -5 mm / N, R d21a =5.9235×10 -6 mm / N, clamping flexibility R for non-standard parabolic airbag support arms da Perform the calculation, namely:

[0285] R da =R d22a +R dz2a +R d21a +R dpa =5.5763×10 -5 mm / N;

[0286] S3: Clamping stiffness K of non-standard parabolic guide arm assembly z Verification calculation:

[0287] According to the R calculated in S1 db =7.8339×10 -5 mm / N, R calculated in S2 da =5.5763×10 - 5 mm / N, clamping stiffness K for non-standard parabolic guide arm assembly zPerform the check calculation, namely:

[0288]

[0289] S4: Composite stiffness K of non-standard parabolic guide arm air suspension system C Verification calculation:

[0290] According to the front guide arm length L b =547mm, length of airbag support arm L a =380mm, airbag stiffness K under rated load A =178.0N / mm, K calculated in S3 z =7457.0N / mm, composite stiffness K of air suspension system C Perform the calculation, namely:

[0291]

[0292] S5: Verification calculation of the offset frequency f0 of the non-standard parabolic guide arm air suspension system:

[0293] According to the rated sprung mass of a single wheel m2 = 6000 kg, K calculated in S4 C =289.93N / mm, and the non-standard parabolic guide arm air suspension offset frequency f0 is checked and calculated, namely:

[0294]

[0295] S6: Verification calculation of the damping ratio ξ of the non-standard parabolic guide arm air suspension system:

[0296] According to the damping coefficient C of the shock absorber d =16110N / ms -1 , shock absorber installation angle α=30°, single wheel rated sprung mass m2=6000kg, K calculated in S4 C =289.93N / mm, and the damping ratio ξ of the non-standard parabolic guide arm air suspension system is verified and calculated, namely:

[0297]

[0298] S7: Stress strength verification calculation of non-standard parabolic guide arm assembly:

[0299] S71: Calculation of the end loads of each non-standard parabolic front guide arm and airbag support arm:

[0300] According to the rated sprung mass of a single wheel m2 = 6000 kg, the number of front guide arms n = 1, the k calculated in step S11 isFb =0.41 and k Fa =0.59, for the end load F of the non-standard front guide arm b1 and the end load F of the airbag support arm a Perform the calculation, namely:

[0301] F b1 =k Fb m29.8=24108N;F a =k Fa m29.8=34692N;

[0302] S72: Calculation and verification of the maximum stress at the root of each non-standard parabolic front guide arm and airbag support arm

[0303] According to the saddle bolt clamping distance U = 180mm, the number of front guide arm pieces n = 1, the front guide arm L b =547mm,h 21 =40mm, L of airbag support arm a =380mm,h 2a =38mm, F calculated in S71 b1 =24108N,F a =34692N, b calculated in step S12 21 =104 mm, b calculated in step S21 2a =104mm, maximum stress at the root of non-standard parabolic front guide arm σ maxb1 and the maximum stress at the root of the airbag support arm σ maxa Perform the calculation, namely:

[0304]

[0305] It can be seen that σ maxb1 and σ maxa are all less than [σ], therefore, the stress intensity requirements are met.

[0306] Prototype vehicle testing demonstrates that the calibration method for the non-standard parabolic guide arm air suspension system established by the present invention is correct. Based on the structural parameters and cross-sectional shapes of the non-standard parabolic guide arm assembly, rated load, airbag stiffness, allowable stress, shock absorber damping coefficient, and installation angle, the system's composite stiffness, suspension offset frequency, suspension system damping ratio, and guide arm stress intensity can be verified. This method ensures that the key parameters of the non-standard parabolic guide arm air suspension system meet design requirements, improving the design level of the trailer air suspension system and the vehicle's ride smoothness and safety. It also reduces design and testing costs and accelerates product development.

[0307] The present invention can be widely used in trailer air suspension applications.

Claims

1. A calibration method for a non-standard parabolic guide arm type air suspension system, comprising a guide arm assembly and an airbag, wherein the guide arm assembly comprises a front guide arm (1) and an airbag support arm (2); the front guide arm (1) is composed of a root straight section, a parabolic section and an end straight section; the end point of the front guide arm (1) does not coincide with the coordinate origin of the parabolic section; based on the structural parameters, rated load and allowable stress of the non-standard parabolic guide arm assembly, the stiffness of the airbag under the rated load, the damping coefficient of the shock absorber and its installation angle, the composite stiffness, suspension frequency deviation, suspension system damping ratio and stress intensity of the non-standard parabolic guide arm type air suspension system are calibrated, characterized in that: The following verification steps are used: S1: Clamping flexibility of the front guide arm of the non-standard parabolic guide arm assembly R db Calculation of S2: Clamping flexibility of the airbag support arm of the non-standard parabolic end guide arm assembly R da Calculation of S3: Clamping stiffness of non-standard parabolic guide arm assembly K z Verification calculation of S4: Composite stiffness of non-standard parabolic guiding arm air suspension system K C Verification calculation of S5: Deviation frequency of non-standard parabolic guiding arm air suspension system f 0 verification calculation; S6: Damping ratio of non-standard parabolic guiding arm air suspension system Verification calculation of S7: Check calculation of stress strength of non-standard parabolic guide arm assembly; S1: Clamping flexibility of the front end guide arm of the non-standard parabolic guide arm assembly R db Calculation: S11: Load distribution ratio coefficient of front guide arm and airbag support arm k Fb and k Fa Calculation: According to the length of the front guide arm L b , the length of the airbag support arm L a , the load distribution ratio coefficient of the front guide arm and the airbag support arm of the guide arm assembly k Fb and k Fa Calculate separately, namely: ； ； S12: Equivalent width of the straight section at the root and end of each front guide arm b 2i and b 1i Calculation: According to the width of the guide arm B , the chamfer radius thickness ratio at both ends of the cross section k r , 0≤ k r ≤1 / 2, number of front guide arms n , the thickness of the straight section at the root of each front guide arm h 2i and the thickness of the straight section at the end h 1i , the equivalent width of the straight section at the root of each front guide arm b 2i and the equivalent width of the end straight section b 1i Perform calculations, i =1,2,…, n ,Right now:: ； ； Where: is the equivalent width reduction coefficient, where 0≤ k r ≤1 / 2, then -0.411≤ ≤0,; when k r =1 / 2, =-0.411, the cross section is arc-shaped, then , ; when k r =0, =0, the cross section is rectangular, then =0, then , ; S13: Parabolic segment coordinate translation of each non-standard parabolic front guide arm x 0i Calculation: According to the number of front guide arm pieces n , the thickness of the straight section at the root of each front guide arm h 2i , the thickness of the straight section at the end h 1i , the length of the straight section at the end L 1i , the length from the root of the parabola segment to the end point of the guide arm L 2p , and the thickness ratio of the parabola segment β i = h 1i / h 2i , the parabola coordinate offset of each non-standard parabola front guide arm x 0i Perform calculations, i =1,…, n , Right now ， i =1,…, n ； S14: Flexibility of the straight section at the end of each non-standard parabolic front guide arm R d1i Calculation: According to the number of front guide arm pieces n , each front end guide arm h 1i , L 1i , elastic modulus E , calculated in S11 k Fb , calculated in S12 b 1i , the flexibility of the straight section at the end of each non-standard parabolic front guide arm R d1i Perform calculations, i =1,2,…, n ,Right now: ， i =1,2,…, n ； S15: Clamping flexibility of the straight section at the root of each non-standard parabolic front guide arm R d2i Calculation: According to the number of front guide arm pieces n , each front end guide arm h 2i , L b , L 2p , saddle bolt clamping distance U , elastic modulus E , calculated in S11 k Fb , calculated in S12 b 2i , the clamping flexibility of the straight section at the root of each non-standard parabolic front guide arm R d2i Perform calculations, i =1,2,…, n ,Right now: ， i =1,2,…, n ； S16: Parabolic segment flexibility of each non-standard parabolic front guide arm R dpi Calculation: S161: cross-section chamfered type, namely: k r ≠0 According to the width of the guide arm B , cross-section chamfered type, that is: k r ≠0, 0< k r ≤1 / 2, -0.41≤ <0, elastic modulus E ;Number of front guide arms n , each front end guide arm L 2p , L 1i , h 2i , h 1i , β i = h 1i / h 2i ; calculated in S11 k Fb , calculated in S12 b 2i , b 1i , calculated in S13 x 0i , the parabolic segment flexibility of each non-standard parabolic front end guide arm with chamfered cross section R dpi Perform calculations, i =1,2,…, n ,Right now: ， i =1,2,…, n ； Where: G Rdpi The cross-section is chamfered i The flexibility coefficient of the parabolic segment of the non-standard parabolic front guide arm is: ， in, is the length from the root of the parabola segment to the origin of the coordinate system, ; S162: rectangular cross section, i.e.: k r =0 According to the width of the guide arm B , the cross section is a right angle type k r =0, elastic modulus E ;Number of front guide arms n , each front end guide arm L 2p , L 1i , h 2i , h 1i , β i = h 1i / h 2i , calculated in S13 x 0i , the parabolic segment flexibility of each non-standard parabolic front end guide arm with a right-angle cross section R dpi It can be expressed as ， i =1,2,…, n ； Where: G Rdp_ZJi The cross section is rectangular i The flexibility coefficient of the parabolic segment of the non-standard parabolic front guide arm is: ; S17: Clamping flexibility of each non-standard parabolic front guide arm R dbi Calculation: According to the number of front guide arm pieces n， Calculated in S14 R d1i , calculated in S15 R d2i , calculated in S16 R dpi , the clamping flexibility of each non-standard parabolic front guide arm R dbi Perform calculations, i =1,2,…, n ,Right now: ， i =1,2,.., n ; S18: Clamping stiffness of non-standard parabolic front guide arm K b and clamping flexibility R db Calculation: According to the number of front guide arm pieces n , calculated in S17 R dbi , clamping stiffness for non-standard parabolic front guide arms K b and clamping flexibility R db Perform the calculation, namely: ； R db = ； The clamping flexibility of the airbag support arm of the non-standard parabolic end guide arm assembly in step S2 R da The calculation of , includes the following steps: S21: Calculation of the equivalent width of each section of the airbag support arm: According to the width of the guide arm B , chamfer radius thickness ratio at both ends of the cross section k r , 0≤ k r ≤1 / 2, equivalent width reduction factor D br , -0.411≤ ≤0, thickness of the straight section at the root of the airbag support arm h 2a , the length of the hanging arm L z2 = h 2a , the thickness of the straight section outside the drop arm h 21a = h 2a , the thickness of the parabolic end of the airbag support arm h 1a ; Equivalent width of the straight section at the root of the airbag support arm b 2a , the equivalent width of the drop arm section b za , the equivalent width of the straight section outside the drop arm b 21a , the equivalent width of the end of the parabola segment b 1a Perform the calculation, namely: ， ， ， ； when k r =1 / 2, arc cross section, D br =-0.411, then , , ， ； when k r =0, rectangular cross section, D br =0, then , , b 21a = B , b 1a = B ; S22: Flexibility of the parabolic segment of the non-standard parabolic airbag support arm R dpa Calculation: S221: cross-section chamfered type, namely: k r ≠0 According to the width of the guide arm B , cross-section chamfered type, k r ≠0, 0< k r ≤1 / 2, -0.41≤ <0, elastic modulus E ; Airbag support arm h 21a , h 1a , the thickness ratio of the parabolic segment of the airbag support arm and the length of the parabola segment L pa , elastic modulus E , calculated in S21 b 21a and b 1a , calculated in step S11 k Fa , the flexibility of the parabolic segment of the non-standard parabolic airbag support arm with chamfered cross section R dpa Perform the calculation, namely: ； Where: The flexibility coefficient of the parabolic segment of the airbag support arm with a chamfered cross section; S222: rectangular cross section, i.e.: k r =0 According to the width of the guide arm B , the cross section is rectangular, that is: k r =0, elastic modulus E ; Airbag support arm h 21a , h 1a , , L pa , elastic modulus E , calculated in step S11 k Fa , the flexibility of the parabolic segment of the airbag support arm with a right angle transverse section R dpa Perform the calculation, namely: ； Where: G Rdpa_ZJ is the flexibility coefficient of the parabolic segment of the airbag support arm with a right-angle cross section, ； S23: Flexibility of the drop arm section of the airbag support arm R dz2a Calculation: According to the airbag support arm h 2a , L 21a , L pa , height of the drop arm h z2 , elastic modulus E , calculated in step S11 k Fa ,in, L 21a is the length of the straight section outside the drop arm; calculated in S21 b za , the flexibility of the vertical arm section of the airbag support arm R dz2a Perform the calculation, namely: ； S24: Flexibility of the straight section at the root of the airbag support arm and the straight section outside the drop arm R d22a and R d21a Calculation: According to the clamping distance of the riding bolt U , airbag support arm L a , h 2a , h 21a , L z2 , L 21a , L pa , elastic modulus E , the equivalent width calculated in S21 b 2a and b 21a , calculated in step S11 k Fa , the flexibility of the straight section at the root of the airbag support arm R d22a , the flexibility of the straight section outside the drop arm R d21a Perform the calculation, namely: ； ； S25: Clamping flexibility of non-standard parabolic airbag support arm R da Calculation: According to the calculation in S22 R dpa , calculated in S23 R dz2a , calculated in S24 R d22a ,and R d21a , clamping flexibility for non-standard parabolic airbag support arms R da Perform the calculation, namely: ； The clamping stiffness of the non-standard parabolic guide arm assembly in step S3 K z The verification calculation includes the following steps: According to the calculation in S1 R db , calculated in S2 R da , the clamping stiffness of the parabolic guide arm assembly K z Perform the check calculation, namely: ； The composite stiffness of the non-standard parabolic guide arm air suspension system in step S4 K C The verification calculation includes the following steps: According to the length of the front guide arm L b , the length of the airbag support arm L a , airbag stiffness under rated load K A , calculated in S3 K z , composite stiffness of non-standard air suspension system K C Perform the check calculation, namely: ； The frequency deviation of the non-standard parabolic guide arm air suspension system in step S5 f The verification calculation of 0 includes the following steps: According to the rated sprung mass of a single wheel m 2, calculated in S4 K C , for non-standard parabolic guide arm air suspension frequency deviation f 0 for verification calculation, namely: ； The damping ratio of the non-standard parabolic guide arm air suspension system in step S6 The verification calculation includes the following steps: According to the damping coefficient of the shock absorber C d , shock absorber installation angle , rated sprung mass of a single wheel m 2. The result of the calibration calculation in S4 K C , the damping ratio of the non-standard parabolic guide arm air suspension system Perform the check calculation, namely: ； The stress strength verification calculation of the non-standard parabolic guide arm assembly in step S7 includes the following steps: S71: Calculation of the end loads of each non-standard parabolic front guide arm and airbag support arm: According to the rated sprung mass of a single wheel m 2. Number of front guide arms n , calculated in step S11 k Fb and k Fa , calculated in S17 R dbi and calculated in S18 K b , for each non-standard front end guide arm end load F bi and the end load of the airbag support arm F a Perform calculations, i =1,2,…, n ,Right now: ， i =1,2,…, n ， ； When the number of front guide arms n =1, ; S72: Calculation and verification of the maximum stress at the root of each non-standard parabolic front guide arm and airbag support arm According to the clamping distance of the riding bolt U , the number of front guide arm pieces n , the front guide arm L b , h 2i , airbag support arm L a , h 2a , calculated in S71 F bi , F a , calculated in step S12 b 2i , calculated in step S21 b 2a , the maximum stress at the root of each non-standard parabolic front guide arm and the maximum stress at the root of the airbag support arm Perform the calculation, namely: ； ； The calculated and and Allowable stress is compared if and are smaller than , then the stress intensity requirement is met, otherwise, the stress intensity requirement is not met.

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