CN105857304B - Based on four-wheel drive car Torque distribution control system - Google Patents
Based on four-wheel drive car Torque distribution control system Download PDFInfo
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- CN105857304B CN105857304B CN201610345190.XA CN201610345190A CN105857304B CN 105857304 B CN105857304 B CN 105857304B CN 201610345190 A CN201610345190 A CN 201610345190A CN 105857304 B CN105857304 B CN 105857304B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W30/00—Purposes of road vehicle drive control systems not related to the control of a particular sub-unit, e.g. of systems using conjoint control of vehicle sub-units, or advanced driver assistance systems for ensuring comfort, stability and safety or drive control systems for propelling or retarding the vehicle
- B60W30/02—Control of vehicle driving stability
- B60W30/045—Improving turning performance
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W10/00—Conjoint control of vehicle sub-units of different type or different function
- B60W10/12—Conjoint control of vehicle sub-units of different type or different function including control of differentials
- B60W10/14—Central differentials for dividing torque between front and rear axles
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W10/00—Conjoint control of vehicle sub-units of different type or different function
- B60W10/18—Conjoint control of vehicle sub-units of different type or different function including control of braking systems
- B60W10/184—Conjoint control of vehicle sub-units of different type or different function including control of braking systems with wheel brakes
- B60W10/188—Conjoint control of vehicle sub-units of different type or different function including control of braking systems with wheel brakes hydraulic brakes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W40/00—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models
- B60W40/10—Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models related to vehicle motion
- B60W40/114—Yaw movement
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W2520/00—Input parameters relating to overall vehicle dynamics
- B60W2520/10—Longitudinal speed
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W2520/00—Input parameters relating to overall vehicle dynamics
- B60W2520/14—Yaw
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W2520/00—Input parameters relating to overall vehicle dynamics
- B60W2520/28—Wheel speed
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W2530/00—Input parameters relating to vehicle conditions or values, not covered by groups B60W2510/00 or B60W2520/00
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W2540/00—Input parameters relating to occupants
- B60W2540/18—Steering angle
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
- B60W2552/00—Input parameters relating to infrastructure
- B60W2552/40—Coefficient of friction
Abstract
The Torque distribution control system based on four-wheel drive car that the invention discloses a kind of, it includes ECU, wheel speed sensor, steering wheel angle sensor, vehicle body velocities sensor, hydraulically controlled brake, yaw-rate sensor, the automatically controlled limited-slip differential of between centers, wherein：Wheel speed sensor, vehicle body velocities sensor, yaw-rate sensor, steering wheel angle sensor are connect with the input terminal of ECU, and the automatically controlled limited-slip differential of between centers and hydraulically controlled brake are connect with ECU output end.The present invention, which applies Torque distribution comprehensively control to automobile and applies between centers torque, to be distributed after control, vehicle shows good power performance and control stability, thus has preferable practicability when application in the being drawn through property, directional stability or steer ability for improving automobile.
Description
Technical field
The invention belongs to four-wheel drive car Handling stability control fields, and in particular to one kind is based on four-wheel drive car
The comprehensive Torque distribution control system of the control of between centers driving moment and wheel braking moment control under steering situation.
Background technique
With the development of automotive engineering, people want the various performances such as vehicle dynamic quality, control stability and safety
Ask higher and higher.Adhesive force of the four-wheel drive technology due to that can make full use of wheel obtains driving force as big as possible, therefore more
All start come more high-grade car and sports car using this technology.
When four-wheel drive car turns to, between centers torque distribution control technology is the key technology of four-wheel drive car, is passed through
Torque distribution between control front and back between centers and left and right wheels makes vehicle make full use of ground to realize the best hauling ability for driving wheel
Face adhesive force, to make automobile adapt to continually changing driving status and surface conditions under steam, reasonably driving moment
Each driving wheel is distributed to, the driving force of each tire is given full play to, makes the wheel controlled acquisition is biggish longitudinally and laterally to adhere to
Power, but it has to be ensured that each driving wheel road surface attachment condition is good after torque reallocation.It is logical with the traction for reaching improvement automobile
The purpose of the property crossed, directional stability and steer ability.
For example, traction control system can more divide the driving moment of front axle when characterization vehicle is understeer
Dispensing outer front-wheel inhibits understeer, and the driving force of outer front-wheel becomes larger at this time.If breaking through road surface limit of adhesion, it will slide
Turn phenomenon, then the lateral force of outer front-wheel will sharply decline, it is clear that this is extremely unsafe for the automobile in steering
Operating condition.As it can be seen that either differential braking control or polling power controlling are all defective.At present, the automobile under steering situation
Control stability and dynamic property is in a kind of fish and bear's paw can not get both under relationship, so, the dynamic property of automobile in order to balance
And control stability, the comprehensive study for distributing between centers driving moment control and wheel braking moment distribution control is that have very much must
It wants.
The invention proposes the comprehensive Torque distribution controls of a kind of control of between centers driving moment and wheel braking moment control
System processed combines electronic control system with tradition machinery control system using four-wheel drive car as research object.According to working as
Vehicle in front driving cycle, the information input acquired by each sensor is to ECU, using the control program of its storage inside, to biography
The various signals of sensor acquisition are analyzed, are judged, calculated and are handled, and are generated signal and are controlled automatically controlled limited-slip differential and hydraulic control
The movement of the execution system of standard brake actively carries out the allotment of front and back driving between centers driving moment and changes corresponding wheel
Brake pressure controls antero posterior axis rotational speed difference and yaw rate in the ideal range, to guarantee peace when motor turning
Full property and stability.
Summary of the invention
The technical problem to be solved by the present invention is to：A kind of Torque distribution control system based on four-wheel drive car is provided
System, to control antero posterior axis rotational speed difference and yaw rate in the ideal range, to guarantee safety when motor turning
Property and stability.
The present invention solves its technical problem, and the following technical solution is employed：
Torque distribution control system provided by the invention based on four-wheel drive car, including ECU, vehicle wheel rotational speed sensing
Device, steering wheel angle sensor, vehicle body velocities sensor, hydraulically controlled brake, yaw-rate sensor, between centers are automatically controlled
Limited-slip differential, wherein：Wheel speed sensor, vehicle body velocities sensor, yaw-rate sensor, steering wheel angle sensing
Device is connect with the input terminal of ECU, and the automatically controlled limited-slip differential of between centers and hydraulically controlled brake are connect with ECU output end.
The Torque distribution control system based on four-wheel drive car is additionally provided with hydraulically controlled brake, in motor turning
When be judged as that the difference between practical yaw velocity and ideal yaw velocity is more than the unstable shape of upper-lower door limit value as ECU
State needs to brake specified wheel to generate additional yaw moment for yaw velocity and control in stability range.
The hydraulically controlled brake, using disk brake, at each hub for vehicle wheel.
The wheel speed sensor, using induction wheel speed sensor, on each hub for vehicle wheel,
For calculating antero posterior axis actual speed difference and monitoring wheel rotation speed signals.
The steering wheel angle sensor, the side using digital steering wheel angle sensor, below steering wheel
Into column, steering wheel angle signal when for acquiring motor turning；It needs when ECU determines motor turning to hydraulic controlling type
When brake applies additional yaw moment, decision goes out the wheel position of additional moment application.
The vehicle body velocities sensor, using magneto-electric speed at sensor, in transmission case body, for acquiring
Vehicle centroid longitudinal velocity, antero posterior axis desired speed difference and limit yaw angular speed when calculating motor turning, and for monitoring
Vehicle body mass center longitudinal speed signal.
The yaw-rate sensor, mounted in armrest box in the following, for measuring the practical yaw velocity of vehicle body, specifically
Difference when being for calculating motor turning between practical yaw velocity and ideal yaw velocity, and for monitoring vehicle body
Yaw rate signal；It is controlled accordingly using the program stored in ECU.
The automatically controlled limited-slip differential of the between centers, using dimerous by satellite differential and electric control clutch
Active electric-controlled type inter-axle differential, between the drive axle of front and back；When turning to when ECU, which is judged as, has wheel excessively to trackslip,
It is reallocated for generating moment of friction with the driving moment to antero posterior axis.
The above-mentioned Torque distribution control system based on four-wheel drive car provided by the invention, purposes are：Improving
Application in the being drawn through property of automobile, directional stability or steer ability.
When the Torque distribution control system based on four-wheel drive car, during Vehicular turn, by each
The speed probe of wheel and other sensors by it is collected include that vehicle wheel rotational speed running condition information is passed to mounted in starting
ECU near machine issues instruction control after ECU is analyzed, judged, calculated and handled to the various signals that sensor acquires
The movement of the execution system of automatically controlled limited-slip differential and hydraulically controlled brake is made, guarantees that vehicle turns to reach control action
To safety and control stability.
The present invention has major advantage below compared with prior art：
Under steering situation, traditional four-wheel drive car has also used traction control system other than differential braking controls,
By the driving moment of driving moment or between centers between control torque distribution device adjustment wheel, additional yaw moment is generated to adjust
The steering characteristic of whole automobile, but it has to be ensured that each driving wheel road surface attachment state is good after driving moment is reallocated.For example,
When characterization vehicle is understeer, the driving moment of the near front wheel can more be distributed to off-front wheel by traction control system
Inhibit understeer, the driving force of off-front wheel becomes larger at this time, if breaking through road surface limit of adhesion, it will phenomenon of trackslipping occur, then
The lateral force of off-front wheel will sharply decline, it is clear that this is extremely unsafe operating condition for the automobile in steering.As it can be seen that
Either differential braking control or polling power controlling are all defective.At present, it can not guarantee automobile under steering situation simultaneously
Control stability and dynamic property.To achieve it, the invention proposes a kind of controls of four-wheel drive car Torque distribution
System.
The defect of used control strategy when the present invention analyzes current Vehicular turn, under previous steering situation
Single carry out braking moment control or torque distribution control to adjust the steering characteristic of automobile, formulate driving force distribution and system
The integrated control strategy of power distribution, and performance requirement is steady to improve the manipulation under steering situation to be proposed to the control strategy of formulation
Qualitative energy and power performance.The control principle for specifically analyzing the distribution of between centers torque and braking torque distribution, determines before being based on
The between centers torque of rear axle rotational speed difference distributes control strategy, improves the power performance of vehicle when turning to, and analyzes between centers torque point
Match the influence of Vehicular turn characteristic.Braking torque distribution control strategy has been determined, has improved the control stability of vehicle when turning to.
The advantage and disadvantage of comprehensive various control algolithms distribute control strategy between centers torque and select PID control, control for braking torque distribution
Policy selection increment type PD control, is finally completed the modeling to Torque distribution integrated control strategy.Related simulation comparison data are asked
Each data graphs in reference book attached drawing module.
The present invention moves under line operating condition and angle step operating condition from single respectively, provides non control system, the distribution control of between centers torque
Steering simulation analysis data under the conditions of system processed and of the invention three kinds of Torque distribution complex control system, by Tables 1 and 2 institute
In place of advantage of the invention known to the correlation data of column.
As shown in Table 1：The distribution control of between centers torque is only carried out to compare and analyze with simulation result when not controlling：
It can be seen that speed of the vehicle in steering procedure be more stable, the slippage rate peak value of driving wheel by also substantially remain in 0.1 with
Under, the dynamic property of vehicle is significantly improved.In steering procedure, torque most of time is shifted to front axle, makes vehicle
Negative understeer obtain certain inhibition, the result is that vehicle steering wheel turn right during yaw velocity absolute value most
0.38rad/s when big value is by without control is reduced to 0.32rad/s；But at the end of steering procedure is fast, between centers torque point
Start to shift torque to rear axle with device, increase the negative understeer trend of vehicle, caused direct result is that automobile is final
Sideslip degree is slightly bigger than normal compared to more uncontrolled situation, increases to -20m by -12.5m；Yaw angle increases to by -0.2rad -
0.28rad.In addition, the excessively phenomenon of trackslipping of driving wheel is improved so that side slip angle peak value when steering wheel is turned right by
0.41rad is reduced to 0.25rad.
Torque distribution comprehensively control is compared and analyzed with the simulation result only carried out under between centers torque distribution control condition：
Vehicle Speed is still able to maintain stabilization in steering procedure, and fluctuating range is very small；The side slip angle of vehicle changes width
Spend small, peak value by 0.25rad is down to 0.034rad when steering wheel is turned right, and meets single variation tendency moved under line operating condition；Yaw angle
Velocity limits are reduced, and peak value is down to 0.22rad/s by 0.32rad/s when steering wheel is turned right, and variation tendency preferably follows
Ideal yaw velocity；The final sideslip degree of automobile is decreased to 8.6m by -20m compared to more apparent less than normal；Vehicular yaw angle exists
It is zeroed after steering, the operation that vehicle driving trace meets driver is intended to.Vehicle is shown in the case where singly moving line steering situation
Good power performance and control stability.
In conclusion the correlation data listed by table 1：After applying the distribution control of between centers torque, Vehicular turn
When power performance make moderate progress, but control stability is not significantly improved, and applies the comprehensive control of Torque distribution
Vehicle shows good power performance and control stability when processed.
As shown in Table 2：The distribution control of between centers torque is only carried out to compare and analyze with simulation result when not controlling：
The stable peak value to a very small extent of the slippage rate of each wheel is decreased to 0.4 by 0.75, and side slip angle peak value is by 0.001rad
0.003rad is increased to, yaw angle increases to 0.42rad by 0.11rad, and yaw velocity peak value is increased to by 0.025rad/s
0.11rad/s.Since slippage rate is lower, side slip angle, yaw angle, yaw velocity peak value etc. all increase, before vehicle
The wheel of axis makes moderate progress with respect to working condition, and lateral traction also increases accordingly, steering behaviour enhancing.Vehicle longitudinal velocity by
45km/h in the case of no control increases to 60km/h, and length travel increases to 16.5m by 3.1m when the distribution of between centers torque controls, hence it is evident that
Improve power performance.
Torque distribution comprehensively control is compared and analyzed with the simulation result only carried out under between centers torque distribution control condition：
Length travel increases to 19.5m by 16.5m, and side slip angle peak change is little, and yaw angle increases to 0.48rad by 0.42rad, horizontal
Pivot angle velocity peak values increase to 0.14rad/s by 0.11rad/s, and meet ideal variation tendency.Due to braking torque distribution device
Left rear wheel is braked, the wheel speed of left rear wheel and slippage rate is caused to be declined in braking process.
In conclusion the correlation data listed by table 2：After applying the distribution control of between centers torque, Vehicular turn
When dynamic property and control stability have certain improvement, but be not significantly improved, and it is comprehensive to apply Torque distribution
Vehicle shows good power performance and control stability when control.
Detailed description of the invention
Fig. 1 is the overall distribution structural schematic diagram of present system；
Fig. 2 is the control flow chart of Torque distribution control system；
Fig. 3 is between centers Torque distribution policy map.
Fig. 4 is between centers torque dispensing controller illustraton of model.
Fig. 5 is between centers distribution torque limit module map.
Fig. 6 is braking torque distribution control strategy figure.
Fig. 7 is braking torque distribution controller model figure.
Fig. 8-15 is step steering simulation analysis curve graph in the case of no control.
Fig. 8 is speed-actual emulation time history.
Fig. 9 is each vehicle wheel rotational speed-actual emulation time history.
Figure 10 is practical, ideal antero posterior axis rotational speed difference-actual emulation time history.
Figure 11 is each wheel slip rate-actual emulation time history.
Figure 12 is length travel-lateral displacement graph of relation.
Figure 13 is side slip angle-actual emulation time history.
Figure 14 is vehicle body yaw angle-actual emulation time history.
Figure 15 is vehicle body yaw velocity-actual emulation time history.
Figure 16-23 is that step turns to simulation analysis curve graph under Torque distribution integrated control strategy.
Figure 16 is speed-actual emulation time history.
Figure 17 is each vehicle wheel rotational speed-actual emulation time history.
Figure 18 is practical, ideal antero posterior axis rotational speed difference-actual emulation time history.
Figure 19 is each wheel slip rate-actual emulation time history.
Figure 20 is length travel-lateral displacement graph of relation.
Figure 21 is side slip angle-actual emulation time history.
Figure 22 is vehicle body yaw angle-actual emulation time history.
Figure 23 is vehicle body yaw velocity-actual emulation time history.
In figure：1.ECU, 2. wheel speed sensors, 3. steering wheel angle sensors, 4. vehicle body velocities sensors, 5. liquid
Pressure controlling brake, 6. yaw-rate sensors, the automatically controlled limited-slip differential of 7. between centers.
Specific embodiment
The present invention is to provide under a kind of steering situation based on four-wheel drive car between centers driving moment control and wheel
The comprehensive Torque distribution control system of braking moment control.When it can be according to Vehicular turn, acquired by the way that sensor is corresponding
The information such as each vehicle wheel rotational speed, vehicle body mass center longitudinal velocity, yaw velocity and steering wheel angle signal, and pass to ECU utilization
Its internally stored program calculates practical antero posterior axis, desired speed difference and the limit, ideal yaw velocity automatically, adopts to sensor
The various signals of collection are analyzed, are judged, calculated and are handled, and are generated signal and are controlled automatically controlled limited-slip differential and hydraulic controlling type system
The movement of the execution system of dynamic device, to guarantee the safety and stability during Vehicular turn.
Below with reference to examples and drawings, the invention will be further described, but does not limit the present invention.
Torque distribution control system provided by the invention based on four-wheel drive car, if structure is as shown in Fig. 1-Fig. 7, packet
Include ECU 1, wheel speed sensor 2, steering wheel angle sensor 3, vehicle body velocities sensor 4, hydraulically controlled brake 5,
The automatically controlled limited-slip differential 7 of yaw-rate sensor 6, between centers.Wherein, wheel speed sensor, vehicle body velocities sensor, sideway
Angular-rate sensor, steering wheel angle sensor are connect with the input terminal of ECU, the automatically controlled limited-slip differential of between centers and hydraulic control
Formula brake is connect with ECU output end.
The ECU 1 (Electronic Control Unit) is electronic control unit near engine,
Also known as " car running computer ", " vehicle-mounted computer " etc., for the various signals that sensor acquires to be analyzed, judge, calculate and located
Reason generates the movement of the execution system of the automatically controlled limited-slip differential of signal control between centers and hydraulically controlled brake, to reach control
Be constructed for guaranteeing Vehicular turn safety and control stability.
The wheel speed sensor 2, for monitoring wheel rotation speed signals, can be adopted on each hub for vehicle wheel
With induction wheel speed sensor.
The steering wheel angle sensor 3, in the steering column below steering wheel, for monitoring steering angle signal,
Digital steering wheel angle sensor can be used.
The vehicle body velocities sensor 4, in transmission case body, for monitoring vehicle body mass center longitudinal speed signal,
It can be using magneto-electric speed at sensor.
The yaw-rate sensor 6 can mounted in armrest box in the following, for monitoring vehicle body yaw rate signal
Using the yaw-rate sensor under Japanese Nissan house flag.
The automatically controlled limited-slip differential 7 of the between centers, between the drive axle of front and back, for the drive between the drive axle of front and back
Kinetic moment is reallocated, can be using by satellite differential and electric control clutch active electric-controlled type axis dimerous
Between differential mechanism.
The invention also includes hydraulically controlled brakes 5, using disk brake, for the external front-wheel in need of work
Or inner rear wheel is braked and guarantees Vehicle turning stability to generate an additional yaw moment.Hydraulic controlling type braking
Device is at each hub for vehicle wheel.
Torque distribution control system provided by the invention based on four-wheel drive car, the course of work are as follows：
1. the specific work process of the execution system of the automatically controlled limited-slip differential of between centers：
At present for the monitoring method of wheel slip state first is that by comparing between left and right wheels or the differential carrier of front and back
Rotational speed difference between body judges the phenomenon of trackslipping of wheel, and corresponding control object is the range of rotational speed difference.Set front axle differential
The rotational speed of shell is front axle revolving speed, and the rotational speed of rear axle differential shell is rear axle revolving speed.When vehicle is on good road
When face is kept straight on, if the equal zero slip phenomenon of front and back wheel, the rotational speed difference of antero posterior axis is 0.But under steering situation, sensor
In the antero posterior axis revolving speed difference signal passed back, not only includes the rotational speed difference as caused by wheel slip, also contain front and back wheel
The rotational speed difference that turning radius is different and occurs.At this point, if using antero posterior axis rotational speed difference be 0 as if target, before and after drive shaft
Between will appear interference, inevitably steering procedure is had an impact.For this purpose, before a kind of ideal under proposing steering situation
Rear axle rotational speed difference is as control target.
In formula：wuIndicate front axle revolving speed, wdIndicate rear axle revolving speed, wflIndicate left front wheel speed；wfrIndicate off-front wheel revolving speed；
wrlIndicate left back wheel speed；wrrIndicate off hind wheel revolving speed.
The wheel speed sensors and vehicle body sensor being mounted at four wheels are respectively by the vehicle wheel rotational speed of monitoring and vehicle body matter
The signals such as heart longitudinal velocity pass to ECU, using the control program of its storage inside, carry out to the various signals of sensor acquisition
Analysis, judgement are calculated and are handled.Wherein practical antero posterior axis rotational speed difference calculation formula is as follows：
Δwm=| wu-wd|
In formula：ΔwmIndicate practical antero posterior axis rotational speed difference.
The present invention considers the torque distribution between the drive shaft of front and back, establishes linear two unmounted model thus, which only protects
Weaving and lateral movement in y-direction of the vehicle around z-axis are stayed, that is, thinks that compartment only carries out the fortune for being parallel to horizontal plane
It is dynamic.The aligning torque of tyre performance variation and the generation of tire caused by ignoring transfer of the load between centers and wheel
Effect, is reduced to a two-wheel vehicle model for automobile.The equation of motion of steering situation lower linear two degrees of freedom car model
As follows：
When automobile driving speed remains unchanged, vehicle will do uniform circular motion after entering stable state, i.e.,Substitution above formula obtains steady-state quantities sensitivity and is：
Wherein：K indicates the stability factor of automobile, and expression formula is
In formula：k1、k2The cornering stiffness of the front and back wheel of automobile is respectively indicated, β indicates that side slip angle, u indicate vehicle centroid
Longitudinal velocity；lf、lrRespectively indicate mass center to antero posterior axis distance；wozThe practical yaw velocity monitored for sensor；δf
Indicate the front wheel angle of automobile；IzIndicate the rotary inertia of automobile about the z axis；L indicates wheelbase.
Motor turning radius expression formula is as available from the above equation：
In formula：R indicates motor turning radius；The stability factor of K expression automobile；The longitudinal velocity of u expression vehicle centroid；
L indicates wheelbase；δfIndicate the front wheel angle of automobile.
Assuming that front and back wheel does not occur phenomenon of trackslipping in steering procedure, mathematical analysis is carried out to linear two-freedom model
Known to：
In formula：Rf、RrThe respectively turning radius of antero posterior axis；R indicates motor turning radius；lf、lrMass center is respectively indicated to arrive
The distance of antero posterior axis；β indicates side slip angle.
Therefore ideal antero posterior axis rotational speed difference calculation formula is as follows：
In formula：vf、vrAnd υ respectively indicates the actual speed of front and back wheel and automobile mass center；Rf、RrRespectively antero posterior axis
Turning radius；rwf、rwrRespectively indicate the rolling radius of front and back wheel；The turning radius of R expression vehicle.
By above formula it is found that only it is to be understood that when the turning radius R and side slip angle β of vehicle can find out motor turning
The desired speed of antero posterior axis is poor.R can be calculated by above-mentioned formula in the present invention, and β can be by directly reading in whole vehicle model.
In the step steering situation of angle, setting vehicle starts to walk to accelerate on good road surface, the bias ratio of antero posterior axis
It is fixed as 0.36:0.64, in order to avoid shift generates unnecessary influence to simulation result in accelerator, vehicle is set with 1
Shelves starting, after simulation time 1s, accelerator open degree reaches 20 °, and remains unchanged.After emulation starts 3s, driver is to steering
Disk inputs one 0 ° to 120 ° of step signal, and snap time 1s then keeps steering wheel angle constant.Accelerator opening amount signal
It is as shown in the figure with steering wheel input signal.Simulation time is set as 8s.Road traveling condition is：In 0~2s, front and back wheel
Attachment coefficient is 0.6, and in 2s to 8s, front-wheel attachment coefficient is 0.1, and rear-wheel attachment coefficient is 0.6.
Above formula, which is substituted into, using initial setting up and the parameter monitored by sensor calculates practical, ideal front and back
Axis rotational speed difference.
The control system selects Position Form PID control, and the input of controller is：
E=Δ wideal-Δwm
In formula：The input of e expression controller；ΔwidealIndicate ideal antero posterior axis rotational speed difference；ΔwmIndicate practical antero posterior axis
Rotational speed difference.
Output quantity is the size of current of motor in the automatically controlled limited-slip differential of between centers, and governing equation is：
In formula：kpIndicate proportionality coefficient, kiIndicate integral coefficient, kdIndicate that differential coefficient, e indicate the input of controller；i
(t) size of current of motor in the automatically controlled limited-slip differential of between centers is indicated.
The control logic of between centers torque distribution is relatively simple, before the difference of current axis revolving speed and rear axle revolving speed is greater than preferably
When rear axle rotational speed difference, determines that front axle appearance is excessively trackslipped, control actuator at this time for more torques and be transported to rear axle.Conversely,
Then determine that rear axle appearance is excessively trackslipped, controls actuator at this time for bigger torque and be transported to front axle.
If vehicle antero posterior axis rotating speed difference is larger, calculated between centers transfer torque can be more than the torque that can be shifted
Therefore maximum value establishes the limit module of between centers transfer torque, as shown in figure 4, guaranteeing that the input of antero posterior axis torque is kept just
Often.
2. the specific work process of the execution system of hydraulically controlled brake：
Be mounted below armrest box yaw-rate sensor by the vehicle body yaw velocity monitored, be mounted on steering wheel
Steering wheel angle sensor in the steering column of lower section is fast by the steering angle monitored and the vehicle body being mounted in transmission case body
Degree sensor will monitor that the signals such as vehicle body mass center longitudinal velocity pass to ECU, using the control program of its storage inside, to biography
The various signals of sensor acquisition are analyzed, are judged, calculated and are handled.Wherein steady-state yaw rate calculation formula is as follows：
In formula：woz)sIndicate steady-state yaw rate；The longitudinal velocity of u expression vehicle centroid；L indicates wheelbase；K indicates vapour
The stability factor of vehicle；δfIndicate the front wheel angle of automobile.
Limit yaw angular speed of the vehicle in steering procedure is：
In formula：woz)maxIndicate limit yaw angular speed；μmaxIndicate ground maximum grip coefficient；G indicates acceleration of gravity；
The longitudinal velocity of u expression vehicle centroid.
Ideal yaw velocity when automobile is under steering situation：
wideal=min | woz)s|,|woz)max|}sign(woz)s)
In formula：widealIndicate ideal yaw velocity；woz)sIndicate steady-state yaw rate；woz)maxIndicate limit yaw
Angular speed.
Define yaw velocity deviation be：
Work as h>When 0, vehicle is negative understeer, works as h<When 0, vehicle is understeer.
In formula:wozFor the practical yaw velocity that sensor monitors, widealFor the ideal yaw angle speed calculated
Degree.
For PD control device, have：
Mb(k)=kph(k)+kd[h(k)-h(k-1)]
In formula, Mb(k) indicate that the kth time sampled output value of system, h (k) indicate the kth time sample input value of system, kpTable
Show proportionality coefficient, kdIndicate differential coefficient.
From the above equation, we can see that：
Mb(k-1)=kph(k-1)+kd[h(k-1)-h(k-2)]
Generate additional yaw moment be：
ΔMb(k)=Mb(k)-Mb(k-1)=kpΔh(k)+kd[Δ h (k)-Δ h (k-1)],
In formula：Δ h (k)=h (k)-h (k-1).ΔMbIndicate that the increment of braking moment, h indicate the inclined of yaw velocity
Difference.
Controller receives the information that vehicle is passed back first, calculates practical yaw velocity and ideal yaw velocity
Value, and increase high and low thresholds on ideal yaw velocity.If practical yaw velocity is in threshold value, then it is assumed that vehicle
Also it is maintained at stable state.If practical yaw acceleration breaks thresholding, determine that vehicle is in unsteady state, at this time increment type
PD algorithm is believed by the increment of the additional yaw moment size needed for being calculated according to input deviation meter, while by steering wheel angle
Number and input deviation signal judgement Vehicular turn characteristic at this time, the wheel position that decision needs to brake out.Then pass through braking
Device and brake piping model converse the brake pressure of needs, and give this variable to brake model.
Each curve graph of simulation analysis is turned to without control situation inferior horn step by comparing Fig. 8-15 and Figure 16-23 is torque point
It is turned to known to each curve graph of simulation analysis with integrated control strategy inferior horn step.
After front-wheel enters low attachment road surface, occurs phenomenon of trackslipping rapidly, wheel speed sensors detect turning for antero posterior axis at this time
Speed difference deviates ideal value, and between centers torque distribution device is started to work, and the dynamic torque for distributing antero posterior axis, antero posterior axis rotational speed difference is very
Fast to restore to perfect condition, the slip rate respectively taken turns is also stabilized in the range of very little.
Since the slippage rate of each wheel is lower, vehicle lateral force when turning to is more sufficient, and in steering procedure, between centers
Torque distribution device always distributes more torque toward rear axle, it is suppressed that the understeer of vehicle.
The understeer degree at vehicle initial stage in steering procedure is more than control range, and braking torque distribution device starts pair
Inner rear wheel braking, produces the understeer trend that additional yaw moment inhibits vehicle.
Since braking torque distribution device brakes inner rear wheel, the wheel speed of inner rear wheel and slippage rate is caused to brake
Declined in the process, improves safety and stability when Vehicular turn.
For simulation analysis curve graph it is found that vehicle longitudinal velocity increases to 58km/h by the 45km/h in the case of no control；
Length travel increases to 19.5m by 3.4m；Side slip angle peak value increases to 0.025rad by 0.005rad；Yaw angle is by 0.11rad
Increase to 0.48rad；Yaw velocity peak value increases to 0.14rad/s by 0.025rad/s.
It should be understood that for those of ordinary skills, it can be modified or changed according to the above description,
And all these modifications and variations should all belong to the protection domain of appended claims of the present invention.
Table 1 is single to move line steering situation-simulation analysis data
2 jiaos of step steering situation-simulation analysis data of table
Claims (10)
1. a kind of Torque distribution control system based on four-wheel drive car, it is characterized in that include ECU, wheel speed sensor,
Steering wheel angle sensor, vehicle body velocities sensor, hydraulically controlled brake, yaw-rate sensor, the automatically controlled limit of between centers
Slip differential, wherein：Wheel speed sensor, vehicle body velocities sensor, yaw-rate sensor, steering wheel angle sensor
It is connect with the input terminal of ECU, the automatically controlled limited-slip differential of between centers and hydraulically controlled brake are connect with ECU output end；
When the vehicle is turning, which acquires each vehicle wheel rotational speed, vehicle body mass center longitudinal velocity, yaw angle speed by the way that sensor is corresponding
Degree and steering wheel angle signal, and pass to ECU to calculate antero posterior axis actual speed automatically poor, preceding using its internally stored program
Rear axle desired speed is poor, limit yaw angular speed and ideal yaw velocity, the various signals of sensor acquisition are analyzed,
Judgement is calculated and is handled, and generates the movement that signal controls the execution system of automatically controlled limited-slip differential and hydraulically controlled brake,
To guarantee the safety and stability during Vehicular turn.
2. the Torque distribution control system according to claim 1 based on four-wheel drive car, it is characterised in that the system
It is additionally provided with hydraulically controlled brake, in motor turning when ECU is judged as practical yaw velocity and ideal yaw velocity
Between difference be more than upper-lower door limit value unsteady state, need to brake specified wheel to generate additional yaw moment
Yaw velocity is controlled in stability range.
3. the Torque distribution control system according to claim 2 based on four-wheel drive car, it is characterised in that described
Hydraulically controlled brake, using disk brake, at each hub for vehicle wheel.
4. the Torque distribution control system according to claim 1 based on four-wheel drive car, it is characterised in that described
Wheel speed sensor, using induction wheel speed sensor, on each hub for vehicle wheel, for calculating antero posterior axis
Actual speed difference and monitoring wheel rotation speed signals.
5. the Torque distribution control system according to claim 1 based on four-wheel drive car, it is characterised in that described
Steering wheel angle sensor, using digital steering wheel angle sensor, in the steering column below steering wheel, for acquiring
Steering wheel angle signal when motor turning；It needs to apply hydraulically controlled brake when ECU determines motor turning additional
When yaw moment, decision goes out the wheel position of additional moment application.
6. the Torque distribution control system according to claim 1 based on four-wheel drive car, it is characterised in that described
Vehicle body velocities sensor, using magneto-electric speed at sensor, in transmission case body, for acquiring the longitudinal speed of vehicle centroid
Degree, antero posterior axis desired speed difference and limit yaw angular speed when calculating motor turning, and for monitoring the longitudinal speed of vehicle body mass center
Spend signal.
7. the Torque distribution control system according to claim 1 based on four-wheel drive car, it is characterised in that described
Yaw-rate sensor is particularly used for calculating automobile mounted in armrest box in the following, for measuring the practical yaw velocity of vehicle body
Difference when steering between practical yaw velocity and ideal yaw velocity, and for monitoring vehicle body yaw velocity letter
Number；It is controlled accordingly using the program stored in ECU.
8. the Torque distribution control system according to claim 1 based on four-wheel drive car, it is characterised in that described
The automatically controlled limited-slip differential of between centers, using by satellite differential and electric control clutch active electric-controlled type between centers dimerous
Differential mechanism, between the drive axle of front and back；When turning to when ECU, which is judged as, has wheel excessively to trackslip, for generating frictional force
Square is reallocated with the driving moment to antero posterior axis.
9. special according to claim 1 to the purposes of any Torque distribution control system based on four-wheel drive car in 8
Sign is application of the system in the being drawn through property, directional stability or steer ability for improving automobile.
10. purposes according to claim 9, it is characterized in that passing through the revolution speed sensing of each wheel during Vehicular turn
Device and other sensors by it is collected include that vehicle wheel rotational speed running condition information passes to the ECU near engine, pass through
After ECU is analyzed, judged, calculated and handled to the various signals that sensor acquires, issues instruction and control automatically controlled slide limiting differential
The movement of the execution system of device and hydraulically controlled brake guarantees Vehicular turn safety and manipulation to reach control action
Stability.
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| DE102016215793B4 (en) | 2016-08-23 | 2018-04-26 | Schaeffler Technologies AG & Co. KG | Vehicle and method for steering the vehicle |
| CN106183892B (en) * | 2016-10-09 | 2018-08-10 | 重庆理工大学 | The experimental model and driving stability control method of electric wheel drive vehicle |
| CN108016441B (en) * | 2016-10-28 | 2019-12-06 | 长城汽车股份有限公司 | vehicle torque control method and system and vehicle |
| DE102017212650B4 (en) * | 2017-07-24 | 2019-02-28 | Magna powertrain gmbh & co kg | Control system in a four-wheel drive motor vehicle and method of control |
| CN109572673B (en) * | 2017-09-29 | 2020-12-25 | 比亚迪股份有限公司 | Hybrid electric vehicle, power system thereof and whole vehicle control method |
| CN109835317B (en) * | 2017-11-29 | 2021-04-02 | 长城汽车股份有限公司 | Steering control method, steering control device, vehicle and storage medium |
| CN108313062B (en) * | 2018-01-25 | 2019-09-03 | 中国第一汽车股份有限公司 | A kind of the torque distribution control method and system of distributed driving electric vehicle |
| CN112937579A (en) * | 2019-11-22 | 2021-06-11 | 北京宝沃汽车股份有限公司 | Vehicle, and control method and control device thereof |
| JP7041704B2 (en) * | 2020-03-12 | 2022-03-24 | 本田技研工業株式会社 | Behavior control device and behavior control method |
| CN111605413B (en) * | 2020-04-28 | 2021-10-08 | 中国第一汽车股份有限公司 | Control method, control device, vehicle and storage medium |
| CN112078381A (en) * | 2020-09-18 | 2020-12-15 | 北京车和家信息技术有限公司 | Torque distribution control method and device, driving system and vehicle |
| CN116968809B (en) * | 2023-09-20 | 2023-11-28 | 博世汽车部件(苏州)有限公司 | Vehicle steering assist system and control unit thereof |
| CN117087628B (en) * | 2023-10-18 | 2023-12-22 | 江苏智能无人装备产业创新中心有限公司 | Double-side independent electric drive unmanned tracked vehicle braking deviation prevention control method |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6189643B1 (en) * | 1997-10-24 | 2001-02-20 | Fuji Jukogyo Kabushiki Kaisha | Differential limiting control apparatus for four wheel drive vehicle |
| CN101070068A (en) * | 2006-05-12 | 2007-11-14 | 三菱自动车工业株式会社 | Vehicle steering control device |
| CN105492288A (en) * | 2013-09-19 | 2016-04-13 | 日立汽车系统株式会社 | Vehicle control apparatus |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3458734B2 (en) * | 1998-04-09 | 2003-10-20 | トヨタ自動車株式会社 | Vehicle motion control device |
| US7503416B2 (en) * | 2005-06-28 | 2009-03-17 | Magna Powertrain Usa, Inc. | Torque distributing drive mechanism with limited slip |
-
2016
- 2016-05-23 CN CN201610345190.XA patent/CN105857304B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6189643B1 (en) * | 1997-10-24 | 2001-02-20 | Fuji Jukogyo Kabushiki Kaisha | Differential limiting control apparatus for four wheel drive vehicle |
| CN101070068A (en) * | 2006-05-12 | 2007-11-14 | 三菱自动车工业株式会社 | Vehicle steering control device |
| CN105492288A (en) * | 2013-09-19 | 2016-04-13 | 日立汽车系统株式会社 | Vehicle control apparatus |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110497900A (en) * | 2019-08-15 | 2019-11-26 | 太原科技大学 | A kind of acoustic filed formula electric car electronic differential stability control method |
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