CN113239471A - Motion modal displacement and force calculation method for three-axis vehicle suspension system - Google Patents

Motion modal displacement and force calculation method for three-axis vehicle suspension system Download PDF

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CN113239471A
CN113239471A CN202110713521.1A CN202110713521A CN113239471A CN 113239471 A CN113239471 A CN 113239471A CN 202110713521 A CN202110713521 A CN 202110713521A CN 113239471 A CN113239471 A CN 113239471A
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displacement
suspension
suspension system
wheel
axle
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CN113239471B (en
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丁飞
刘杰
谢泽军
单红洋
陈佳林
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Hunan University
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Hunan University
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    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00—Computer-aided design [CAD]
    • G06F30/10—Geometric CAD
    • G06F30/15—Vehicle, aircraft or watercraft design
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00—Computer-aided design [CAD]
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    • G—PHYSICS
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    • G06F—ELECTRIC DIGITAL DATA PROCESSING
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    • G06F2119/14—Force analysis or force optimisation, e.g. static or dynamic forces

Abstract

The invention discloses a method for calculating motion modal displacement and force of a triaxial vehicle suspension system, which aims at the triaxial vehicle suspension system containing vertical/pitching coupling and side-tipping/warping coupling.A triaxial front and rear suspension system is firstly subjected to equivalence at the front and rear parts of a mass center according to force and moment balance to form a virtual equivalent front and rear suspension system; the motion characteristic of the original suspension system is expressed by the master motion of the virtual suspension and the slave motion of the original front and rear suspensions relative to the virtual front and rear suspensions. Secondly, according to the definition of the equidirectional bouncing, pitching motion, rolling motion and warping motion of the suspension system, the displacement of the upper and lower connecting points of the original suspension is combined, the main motion modal displacement of the virtual suspension system and the slave motion modal displacement of the original front and rear suspensions relative to the virtual front and rear suspensions are calculated, and a modal displacement transformation matrix expressed by the movement of the connecting points to the master and slave modal motion is obtained. And finally, obtaining a modal force transformation matrix from the modal displacement transformation matrix, and calculating the master-slave modal force of the suspension system.

Description

Motion modal displacement and force calculation method for three-axis vehicle suspension system
Technical Field
The invention relates to the technical field of automobile engineering, in particular to a method for calculating motion mode displacement and force of a three-axis vehicle suspension system.
Background
The vehicle has seven coupled motion modes during running, namely, the dominant vertical, pitch and roll modes of the vehicle body and the dominant vertical, pitch, roll and twist modes of the wheel set. When the vehicle runs, vibration modes are mutually coupled, namely coupled vibration generated by the suspended mass and the non-suspended mass of the automobile, so that the running smoothness of the vehicle is reduced, the comfort of a driver is also reduced, and the condition is more serious for a three-axis vehicle. The motion mode calculation of the suspension system of the vehicle stays in the category of two-axis vehicles, for example, the early MIT performs the motion mode calculation of the suspension system of the passenger vehicle by a coordinate transformation method. The modal energy method can also be used for estimating the motion mode of the vehicle, the modal energy method needs to measure the motion modal energy in real time, and parameters such as displacement, speed and the like of the vehicle moving in the modes in various states need to be known when the modal energy method is used for analysis. Before solving the motion parameters of each mode of the vehicle, the parameters of the overall motion of the vehicle in three-dimensional coordinates and the mode matrix are firstly known. The modal energy method can be suitable for a two-axle vehicle suspension system, but cannot be suitable for a three-axle vehicle suspension system, and the calculation process is relatively complex and the calculation efficiency is low.
Disclosure of Invention
The invention aims to provide a displacement and force calculation method suitable for a motion mode of a three-axis vehicle suspension system, which can control the vertical/pitching and rolling/warping coupling degrees of the suspension system in the design stage of the three-axis vehicle suspension system, can also be used as a control strategy for decoupling vehicle body motion of an active suspension, and provides corresponding guidance for the design of the three-axis vehicle suspension system.
Therefore, the technical scheme adopted by the invention is as follows: a motion mode displacement and force calculation method for a three-axis vehicle suspension system comprises the following steps:
1) acquiring construction data and driving data of a vehicle;
2) establishing a three-axis vehicle suspension mounting mode and a position model diagram according to the construction data and the driving data;
the three-axle vehicle suspension mounting mode and position model comprises six modules which are respectively a left front wheel suspension system, a right front wheel suspension system, a left middle wheel suspension system, a right middle wheel suspension system, a left rear wheel suspension system and a right rear wheel suspension system, wherein each suspension system has own sprung mass spring stiffness ksUnsprung mass spring stiffness ktSprung mass damping CsAnd unsprung mass damping CtWherein:
ksfl、ktfl、Csfl、Ctflthe spring stiffness, unsprung mass spring stiffness, sprung mass damping, unsprung mass damping of the left front wheel suspension system are respectively; k is a radical ofsfr、ktfr、Csfr、CtfrThe spring rate, unsprung mass spring rate, sprung mass damping, unsprung mass damping of the right front wheel suspension system respectively;
ksml、ktml、Csml、Ctmlrespectively the sprung mass spring rate, the unsprung mass spring rate, the sprung mass damping, the unsprung mass damping, k, of the left-center wheel suspension systemsmr、ktmr、Csmr、CtmrThe spring stiffness, unsprung mass spring stiffness, sprung mass damping and unsprung mass damping of the right middle wheel suspension system respectively;
ksrl、ktrl、Csrl、Ctrlrespectively the sprung mass spring rate, the unsprung mass spring rate, the sprung mass damping, the unsprung mass damping, k, of the left rear wheel suspension systemsrr、ktrr、Csrr、CtrrThe spring stiffness, unsprung mass spring stiffness, sprung mass damping and unsprung mass damping of the right rear wheel suspension system are respectively;
3) calculating the motion mode displacement of the three-axis vehicle suspension system according to the definitions of the equidirectional bouncing, pitching, rolling and warping motions of the suspension system;
the method comprises the steps that a triaxial front and rear suspension system is subjected to equivalence in the front or the rear of a mass center according to force and moment balance to form a virtual equivalent front and rear suspension system, the motion characteristics of an original suspension system are jointly expressed by the main motion of a virtual suspension and the auxiliary motion of the original front and rear suspensions relative to the virtual front and rear suspensions, and therefore a motion mode displacement calculation schematic diagram of the triaxial vehicle suspension system is constructed. In concrete equivalence, the middle axle and the rear axle may be equivalent to a virtual rear suspension, or the middle axle and the front axle may be equivalent to a virtual front suspension.
In a three-axle vehicle suspension system motion modal displacement calculation schematic diagram, lFL、lFR、lL、lRRespectively the distances from the center of mass to the left side of the front shaft, the right side of the front shaft, the left side of the equivalent rear shaft and the right side of the equivalent rear shaft, a is the distance from the center of mass to the front shaft, b is the distance from the center of mass to the equivalent rear shaft, and b is the distance from the center of mass to the equivalent rear shaftMIs the distance from the equivalent rear axle to the original middle axle, bRFL, FR, ML, MR, RL, RR, L, R represent the left front wheel, right front wheel, left middle wheel, right middle wheel, left rear wheel, right rear wheel, equivalent rear left wheel and equivalent rear right wheel respectively, Z is the distance from the equivalent rear axle to the original rear axleFL、ZFR、ZML、ZMR、ZRL、ZRRRespectively, a suspension displacement of a left front wheel, a suspension displacement of a right front wheel, a suspension displacement of a left middle wheel, a suspension displacement of a right middle wheel, a suspension displacement of a left rear wheel, a suspension displacement of a right rear wheel, and ZL、ZRRespectively representing the suspension displacement of the left wheel of the equivalent rear axle and the suspension displacement of the rear wheel of the equivalent rear axle;
the front axle displacement of the vehicle can be obtained by the suspension displacement
Figure BDA0003134288580000031
And displacement of equivalent rear axle
Figure BDA0003134288580000032
Then, corresponding displacements can be respectively calculated;
vertical displacement at the centroid:
Figure BDA0003134288580000041
pitch angle displacement:
Figure BDA0003134288580000042
displacement of roll angle:
Figure BDA0003134288580000043
twist angular displacement:
Figure BDA0003134288580000051
left rear pitch angle displacement:
Figure BDA0003134288580000052
right rear pitch angle displacement:
Figure BDA0003134288580000053
4) establishing a modal equation according to the mounting mode of the suspension of the three-axis vehicle, the balance force of the position model and the master-slave modal displacement in the step 3);
and performing equivalent treatment on the rear two shafts to obtain force and moment balance equations in all directions:
vertical direction:
Figure BDA0003134288580000054
pitching:
FP＝(FFL+FFR)a-(FL+FR)b＝(FFL+FFR)a-(FML+FMR+FRL+FRR)b
side rolling:
FR＝(FFLlFL+FLlL)-(FFRlFR+FRlR)＝FFLlFL+(FML+FRL)lL-FFRlFR-(FMR+FRR)lR
and (3) twisting:
FW＝(FFLlFL-FFRlFR)a-(FLlL-FRlR)b＝(FFLlFL-FFRlFR)a-[(FML+FRL)lL-(FMR+FRR)lR]b
the following constraints are added due to the connection relationship of the two shafts at the back:
FPL＝FMLbM-FRLbR
FPR＝FMRbM-FRRbR
wherein FFL、FFR、FML、FMR、FRL、FRRRespectively the suspension forces of the left side of the front axle, the right side of the front axle, the left side of the center axle, the right side of the center axle, the left side of the rear axle and the right side of the rear axle of the vehicle, wherein a is the distance from the center of mass to the front axle, b is the distance from the center of mass to the equivalent rear axle, and l isFL、lFR、lL、lRDistances from the center of mass to the left side of the front axle, the right side of the front axle, the left side of the equivalent rear axle and the right side of the equivalent rear axle, respectively, FB、FP、FR、FWRespectively equivalent resultant forces in vertical direction, pitching direction, side-tipping direction and twisting direction;
the modal tire force can be expressed according to the force balance equation as:
Figure BDA0003134288580000061
wherein Ffl、Ffr、Fml、Fmr、Frl、FrrThe tire forces of the left side of the front axle, the right side of the front axle, the left side of the center axle, the right side of the center axle, the left side of the rear axle and the right side of the rear axle of the vehicle are respectivelyf、lm、lrEach being one half of the length of the front, middle and rear shafts, af、bm、brRespectively the distances from the center of mass to the front, middle and rear axes;
further embodying the tire force expression:
Figure BDA0003134288580000071
wherein k istfl、ktfr、ktml、ktmr、ktrl、ktrrSpring rates of the front wheel left suspension, the front wheel right suspension, the middle wheel left suspension, the middle wheel right suspension, the rear wheel left suspension and the rear wheel right suspension, respectively, and z is the samefl、zfr、zml、zmr、zrl、zrrRespectively, suspension displacement on each wheel, wfl、wfr、wml、wmr、wrl、wrrRespectively inputting the road interference displacement of each wheel, z is the vertical displacement of the centroid,
Figure BDA0003134288580000073
for roll angle, theta for pitch angle, thetatlAnd thetatrThe pitch angles of the left and right balance suspension frames are respectively;
from this, the modal equation can be derived:
Figure BDA0003134288580000072
preferably, in step 1), the vehicle construction data is provided by a manufacturer, and the vehicle is monitored from time to time during the driving of the vehicle, so as to obtain the driving data of the vehicle.
The invention has the beneficial effects that:
1. in the prior art, the motion mode estimation of a suspension system of a vehicle is based on two axes, and the three-axis vehicle suspension system is equivalent at the front part and the rear part of a mass center according to force and moment balance through a three-axis front and rear suspension system, so that the three-axis vehicle suspension system is equivalent to a modeling method of a virtual two-axis suspension system, and a whole vehicle coupling motion model is established; and calculating the master-slave mode displacement and the master-slave mode force according to the motion characteristics of the suspension system and the displacement of the connecting point. The calculation method can control the vertical/pitching and rolling/warping coupling degree of the suspension system in the design stage of the suspension system, and can also be used as a control strategy for decoupling vehicle body motion of the active suspension to provide corresponding guidance for the design of the three-axis vehicle suspension system.
2. Compared with a common modal energy method, the method has higher calculation efficiency. The modal energy method needs to measure the motion modal energy in real time, and parameters such as displacement, speed and the like of the vehicle moving in the modes in various states need to be known when the modal energy method is analyzed.
Drawings
Fig. 1 is a diagram of a three-axle vehicle suspension mounting manner and position model.
Fig. 2 is a schematic diagram of a motion mode displacement calculation of a three-axis vehicle suspension system.
Detailed Description
The invention will be further illustrated by the following examples in conjunction with the accompanying drawings:
a motion mode displacement and force calculation method for a three-axis vehicle suspension system comprises the following steps:
1) and acquiring construction data and driving data of the vehicle.
In step 1), the construction data of the vehicle may be provided by the manufacturer; monitoring the automobile in real time in the driving process of the automobile so as to obtain driving data of the automobile; but is not limited thereto.
2) And establishing a three-axis vehicle suspension mounting mode and a position model diagram according to the construction data and the driving data.
As shown in FIG. 1The three-axle vehicle suspension mounting mode and position model diagram comprises six modules which are respectively a left front wheel suspension system, a right front wheel suspension system, a left middle wheel suspension system, a right middle wheel suspension system, a left rear wheel suspension system and a right rear wheel suspension system, and each suspension system has own sprung mass spring stiffness ksUnsprung mass spring stiffness ktSprung mass damping CsAnd unsprung mass damping CtWherein:
ksfl、ktfl、Csfl、Ctflthe spring stiffness, unsprung mass spring stiffness, sprung mass damping, unsprung mass damping of the left front wheel suspension system are respectively; k is a radical ofsfr、ktfr、Csfr、CtfrThe spring rate, unsprung mass spring rate, sprung mass damping, unsprung mass damping of the right front wheel suspension system respectively;
ksml、ktml、Csml、Ctmlrespectively the sprung mass spring rate, the unsprung mass spring rate, the sprung mass damping, the unsprung mass damping, k, of the left-center wheel suspension systemsmr、ktmr、Csmr、CtmrThe spring stiffness, unsprung mass spring stiffness, sprung mass damping and unsprung mass damping of the right middle wheel suspension system respectively;
ksrl、ktrl、Csrl、Ctrlrespectively the sprung mass spring rate, the unsprung mass spring rate, the sprung mass damping, the unsprung mass damping, k, of the left rear wheel suspension systemsrr、ktrr、Csrr、CtrrThe spring rate, unsprung mass spring rate, sprung mass damping and unsprung mass damping of the right rear wheel suspension system are respectively.
3) And calculating the motion mode displacement of the three-axis vehicle suspension system according to the definition of the equidirectional bouncing, pitching, rolling and warping motions of the suspension system.
The method comprises the steps that a triaxial front and rear suspension system is subjected to equivalence in the front or the rear of a mass center according to force and moment balance to form a virtual equivalent front and rear suspension system, the motion characteristics of an original suspension system are jointly expressed by the main motion of a virtual suspension and the auxiliary motion of the original front and rear suspensions relative to the virtual front and rear suspensions, and therefore a motion mode displacement calculation schematic diagram of the triaxial vehicle suspension system is constructed. In concrete equivalence, the middle axle and the rear axle may be equivalent to a virtual rear suspension, or the middle axle and the front axle may be equivalent to a virtual front suspension.
As shown in FIG. 2, in the three-axle vehicle suspension system motion modal displacement calculation schematic diagram, lFL、lFR、lL、lRRespectively the distances from the center of mass to the left side of the front shaft, the right side of the front shaft, the left side of the equivalent rear shaft and the right side of the equivalent rear shaft, a is the distance from the center of mass to the front shaft, b is the distance from the center of mass to the equivalent rear shaft, and b is the distance from the center of mass to the equivalent rear shaftMIs the distance from the equivalent rear axle to the original middle axle, bRFL, FR, ML, MR, RL, RR, L, R represent the left front wheel, right front wheel, left middle wheel, right middle wheel, left rear wheel, right rear wheel, equivalent rear left wheel and equivalent rear right wheel respectively, Z is the distance from the equivalent rear axle to the original rear axleFL、ZFR、ZML、ZMR、ZRL、ZRRRespectively, a suspension displacement of a left front wheel, a suspension displacement of a right front wheel, a suspension displacement of a left middle wheel, a suspension displacement of a right middle wheel, a suspension displacement of a left rear wheel, a suspension displacement of a right rear wheel, and ZL、ZRRespectively representing the suspension displacement of the equivalent rear axle left wheel and the suspension displacement of the equivalent rear axle rear wheel.
The front axle displacement of the vehicle can be obtained by the suspension displacement
Figure BDA0003134288580000101
And displacement of equivalent rear axle
Figure BDA0003134288580000102
Then, corresponding displacements can be respectively calculated;
vertical displacement at the centroid:
Figure BDA0003134288580000103
pitch angle displacement:
Figure BDA0003134288580000111
displacement of roll angle:
Figure BDA0003134288580000112
twist angular displacement:
Figure BDA0003134288580000113
left rear pitch angle displacement:
Figure BDA0003134288580000114
right rear pitch angle displacement:
Figure BDA0003134288580000115
4) and 3) establishing a modal equation according to the mounting mode of the suspension of the three-axis vehicle, the balance force of the position model and the master-slave modal displacement in the step 3).
And performing equivalent treatment on the rear two shafts to obtain force and moment balance equations in all directions:
vertical direction:
Figure BDA0003134288580000121
pitching:
FP＝(FFL+FFR)a-(FL+FR)b＝(FFL+FFR)a-(FML+FMR+FRL+FRR)b
side rolling:
FR＝(FFLlFL+FLlL)-(FFRlFR+FRlR)＝FFLlFL+(FML+FRL)lL-FFRlFR-(FMR+FRR)lR
and (3) twisting:
FW＝(FFLlFL-FFRlFR)a-(FLlL-FRlR)b＝(FFLlFL-FFRlFR)a-[(FML+FRL)lL-(FMR+FRR)lR]b
the following constraints are added due to the connection relationship of the two shafts at the back:
FPL＝FMLbM-FRLbR
FPR＝FMRbM-FRRbR
wherein FFL、FFR、FML、FMR、FRL、FRRRespectively the suspension forces of the left side of the front axle, the right side of the front axle, the left side of the center axle, the right side of the center axle, the left side of the rear axle and the right side of the rear axle of the vehicle, wherein a is the distance from the center of mass to the front axle, b is the distance from the center of mass to the equivalent rear axle, and l isFL、lFR、lL、lRDistances from the center of mass to the left side of the front axle, the right side of the front axle, the left side of the equivalent rear axle and the right side of the equivalent rear axle, respectively, FB、FP、FR、FWRespectively the equivalent resultant forces in the vertical, pitch, roll and warp directions.
The modal tire force can be expressed according to the force balance equation as:
Figure BDA0003134288580000131
wherein Ffl、Ffr、Fml、Fmr、Frl、FrrRespectively the left side of a front axle, the right side of the front axle, the left side of a middle axle of the vehicle,Tire force of right side of center axle, left side of rear axle and right side of rear axle,/f、lm、lrEach being one half of the length of the front, middle and rear shafts, af、bm、brRespectively the distances from the center of mass to the front, middle and rear axes;
further embodying the tire force expression:
Figure BDA0003134288580000132
wherein k istfl、ktfr、ktml、ktmr、ktrl、ktrrSpring rates of the front wheel left suspension, the front wheel right suspension, the middle wheel left suspension, the middle wheel right suspension, the rear wheel left suspension and the rear wheel right suspension, respectively, and z is the samefl、zfr、zml、zmr、zrl、zrrRespectively, suspension displacement on each wheel, wfl、wfr、wml、wmr、wrl、wrrRespectively inputting the road interference displacement of each wheel, z is the vertical displacement of the centroid,
Figure BDA0003134288580000133
for roll angle, theta for pitch angle, thetatlAnd thetatrThe pitch angles of the left and right balance suspension frames are respectively;
from this, the modal equation can be derived:
Figure BDA0003134288580000141
the method of the invention has the following steps: firstly, carrying out equivalence on a front suspension system and a rear suspension system of a three-axis according to force and moment balance at the front part and the rear part of a mass center to form a virtual equivalent front suspension system and a virtual equivalent rear suspension system; the motion characteristic of the original suspension system is expressed by the master motion of the virtual suspension and the slave motion of the original front and rear suspensions relative to the virtual front and rear suspensions. Secondly, according to the definition of the equidirectional bouncing, pitching motion, rolling motion and warping motion of the suspension system, the displacement of the upper and lower connecting points of the original suspension is combined, the main motion modal displacement of the virtual suspension system and the slave motion modal displacement of the original front and rear suspensions relative to the virtual front and rear suspensions are calculated, and therefore a modal displacement transformation matrix expressed by the movement of the connecting points to the master and slave modal motion is obtained. And finally, according to the energy conservation theorem of the system, obtaining a modal force transformation matrix from the modal displacement transformation matrix, and calculating the master-slave modal force of the suspension system.

Claims (2)

1. A three-axis vehicle suspension system motion mode displacement and force calculation method is characterized by comprising the following steps:
1) acquiring construction data and driving data of a vehicle;
2) establishing a three-axle vehicle suspension mounting mode and a position model according to the construction data and the driving data;
the three-axle vehicle suspension mounting mode and position model comprises six modules which are respectively a left front wheel suspension system, a right front wheel suspension system, a left middle wheel suspension system, a right middle wheel suspension system, a left rear wheel suspension system and a right rear wheel suspension system, wherein each suspension system has own sprung mass spring stiffness ksUnsprung mass spring stiffness ktSprung mass damping CsAnd unsprung mass damping CtWherein:
ksfl、ktfl、Csfl、Ctflthe spring stiffness, unsprung mass spring stiffness, sprung mass damping, unsprung mass damping of the left front wheel suspension system are respectively; k is a radical ofsfr、ktfr、Csfr、CtfrThe spring rate, unsprung mass spring rate, sprung mass damping, unsprung mass damping of the right front wheel suspension system respectively;
ksml、ktml、Csml、Ctmlrespectively the sprung mass spring rate, the unsprung mass spring rate, the sprung mass damping, the unsprung mass damping, k, of the left-center wheel suspension systemsmr、ktmr、Csmr、CtmrThe rigidity of the sprung mass spring, the rigidity of the unsprung mass spring and the rigidity of the sprung mass spring of the right middle wheel suspension system are respectivelyMass damping, unsprung mass damping;
ksrl、ktrl、Csrl、Ctrlrespectively the sprung mass spring rate, the unsprung mass spring rate, the sprung mass damping, the unsprung mass damping, k, of the left rear wheel suspension systemsrr、ktrr、Csrr、CtrrThe spring stiffness, unsprung mass spring stiffness, sprung mass damping and unsprung mass damping of the right rear wheel suspension system are respectively;
3) calculating the motion mode displacement of the three-axis vehicle suspension system according to the definitions of the equidirectional bouncing, pitching, rolling and warping motions of the suspension system;
the method comprises the steps that a triaxial front and rear suspension system is subjected to equivalence in the front or the rear of a mass center according to force and moment balance to form a virtual equivalent front and rear suspension system, the motion characteristics of an original suspension system are jointly expressed by the main motion of a virtual suspension and the auxiliary motion of the original front and rear suspensions relative to the virtual front and rear suspensions, and therefore a motion mode displacement calculation schematic diagram of the triaxial vehicle suspension system is constructed. In concrete equivalence, the middle axle and the rear axle may be equivalent to a virtual rear suspension, or the middle axle and the front axle may be equivalent to a virtual front suspension.
In a three-axle vehicle suspension system motion modal displacement calculation schematic diagram, lFL、lFR、lL、lRRespectively the distances from the center of mass to the left side of the front shaft, the right side of the front shaft, the left side of the equivalent rear shaft and the right side of the equivalent rear shaft, a is the distance from the center of mass to the front shaft, b is the distance from the center of mass to the equivalent rear shaft, and b is the distance from the center of mass to the equivalent rear shaftMIs the distance from the equivalent rear axle to the original middle axle, bRFL, FR, ML, MR, RL, RR, L, R represent the left front wheel, right front wheel, left middle wheel, right middle wheel, left rear wheel, right rear wheel, equivalent rear left wheel and equivalent rear right wheel respectively, Z is the distance from the equivalent rear axle to the original rear axleFL、ZFR、ZML、ZMR、ZRL、ZRRRespectively, a suspension displacement of a left front wheel, a suspension displacement of a right front wheel, a suspension displacement of a left middle wheel, a suspension displacement of a right middle wheel, a suspension displacement of a left rear wheel, a suspension displacement of a right rear wheel, and ZL、ZRRespectively representing equivalent rear axlesSuspension displacement of the left wheel and suspension displacement of the rear wheel of the equivalent rear axle;
the front axle displacement of the vehicle can be obtained by the suspension displacement
Figure FDA0003134288570000021
And displacement of equivalent rear axle
Figure FDA0003134288570000022
Then, corresponding displacements can be respectively calculated;
vertical displacement at the centroid:
Figure FDA0003134288570000031
pitch angle displacement:
Figure FDA0003134288570000032
displacement of roll angle:
Figure FDA0003134288570000033
twist angular displacement:
Figure FDA0003134288570000041
left rear pitch angle displacement:
Figure FDA0003134288570000042
right rear pitch angle displacement:
Figure FDA0003134288570000043
4) establishing a modal equation according to the mounting mode of the suspension of the three-axis vehicle, the balance force of the position model and the master-slave modal displacement in the step 3);
and performing equivalent treatment on the rear two shafts to obtain force and moment balance equations in all directions:
vertical direction:
Figure FDA0003134288570000044
pitching:
FP＝(FFL+FFR)a-(FL+FR)b＝(FFL+FFR)a-(FML+FMR+FRL+FRR)b
side rolling:
FR＝(FFLlFL+FLlL)-(FFRlFR+FRlR)＝FFLlFL+(FML+FRL)lL-FFRlFR-(FMR+FRR)lR
and (3) twisting:
FW＝(FFLlFL-FFRlFR)a-(FLlL-FRlR)b＝(FFLlFL-FFRlFR)a-[(FML+FRL)lL-(FMR+FRR)lR]b
the following constraints are added due to the connection relationship of the two shafts at the back:
FPL＝FMLbM-FRLbR
FPR＝FMRbM-FRRbR
wherein FFL、FFR、FML、FMR、FRL、FRRRespectively a front axle left side, a front axle right side, a middle axle left side, a middle axle right side and a rear axle of the vehicleSuspension forces on the left and right sides of the rear axle, a being the distance from the center of mass to the front axle, b being the distance from the center of mass to the equivalent rear axle,/FL、lFR、lL、lRDistances from the center of mass to the left side of the front axle, the right side of the front axle, the left side of the equivalent rear axle and the right side of the equivalent rear axle, respectively, FB、FP、FR、FWRespectively equivalent resultant forces in vertical direction, pitching direction, side-tipping direction and twisting direction;
the modal tire force can be expressed according to the force balance equation as:
Figure FDA0003134288570000051
wherein Ffl、Ffr、Fml、Fmr、Frl、FrrThe tire forces of the left side of the front axle, the right side of the front axle, the left side of the center axle, the right side of the center axle, the left side of the rear axle and the right side of the rear axle of the vehicle are respectivelyf、lm、lrEach being one half of the length of the front, middle and rear shafts, af、bm、brRespectively the distances from the center of mass to the front, middle and rear axes;
further embodying the tire force expression:
Figure FDA0003134288570000061
wherein k istfl、ktfr、ktml、ktmr、ktrl、ktrrSpring rates of the front wheel left suspension, the front wheel right suspension, the middle wheel left suspension, the middle wheel right suspension, the rear wheel left suspension and the rear wheel right suspension, respectively, and z is the samefl、zfr、zml、zmr、zrl、zrrRespectively, suspension displacement on each wheel, wfl、wfr、wml、wmr、wrl、wrrRespectively inputting the road interference displacement of each wheel, z is the vertical displacement of the centroid,
Figure FDA0003134288570000062
for roll angle, theta for pitch angle, thetatlAnd thetatrThe pitch angles of the left and right balance suspension frames are respectively;
from this, the modal equation can be derived:
Figure FDA0003134288570000063
2. the method of calculating modal motion displacement and force of a three-axis vehicle suspension system of claim 1, wherein: in step 1), the construction data of the vehicle is provided by a manufacturer, and the vehicle is monitored from time to time during the driving process of the vehicle, so as to obtain the driving data of the vehicle.
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090062984A1 (en) * 2005-09-22 2009-03-05 Peugeot Citroen Automobiles Sa Suspension control device, vehicle comprising said device, production method thereof and associated program
US20170240017A1 (en) * 2016-02-24 2017-08-24 Tenneco Automotive Operating Company Inc. System and method for controlling dampers of an active suspension system
CN109591537A (en) * 2019-01-25 2019-04-09 成都西汽研车辆技术开发有限公司 A kind of automotive semi-active suspension control system and method
CN109858156A (en) * 2019-01-31 2019-06-07 东南大学 Vehicle and structural information recognition methods simultaneously based on vehicle bridge coupling vibration
CN110712491A (en) * 2019-10-16 2020-01-21 湖南大学 Layered control method, system and medium for vehicle modal decoupling
CN111832119A (en) * 2020-06-23 2020-10-27 恒大新能源汽车投资控股集团有限公司 Optimization method and device for vehicle suspension system
CN112744227A (en) * 2021-01-21 2021-05-04 清华大学 Multi-mode land-air amphibious vehicle take-off and landing control method and device and computer storage medium

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090062984A1 (en) * 2005-09-22 2009-03-05 Peugeot Citroen Automobiles Sa Suspension control device, vehicle comprising said device, production method thereof and associated program
US20170240017A1 (en) * 2016-02-24 2017-08-24 Tenneco Automotive Operating Company Inc. System and method for controlling dampers of an active suspension system
CN109591537A (en) * 2019-01-25 2019-04-09 成都西汽研车辆技术开发有限公司 A kind of automotive semi-active suspension control system and method
CN109858156A (en) * 2019-01-31 2019-06-07 东南大学 Vehicle and structural information recognition methods simultaneously based on vehicle bridge coupling vibration
CN110712491A (en) * 2019-10-16 2020-01-21 湖南大学 Layered control method, system and medium for vehicle modal decoupling
CN111832119A (en) * 2020-06-23 2020-10-27 恒大新能源汽车投资控股集团有限公司 Optimization method and device for vehicle suspension system
CN112744227A (en) * 2021-01-21 2021-05-04 清华大学 Multi-mode land-air amphibious vehicle take-off and landing control method and device and computer storage medium

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
张邦基等: "装有动力调节悬架系统车辆的频域建模与仿真", 《湖南大学学报(自然科学版)》 *

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