阅读说明：本技术 利用转向扭矩叠加的牵引转向补偿 (Compensation is pulled round using steering torque superposition ) 是由 G·德波拉爱德华多 于 2019-05-07 设计创作，主要内容包括：一种用于校正牵引转向事件的系统包括输入方向盘角度函数以识别方向盘角度增益的方向盘角度。将方向盘速度输入方向盘速度函数以识别方向盘速度增益。将车辆速率输入车辆速率函数以识别车辆速率增益。将推进马达扭矩输入马达扭矩函数以识别推进马达扭矩增益。将车辆横摆角速率输入横摆角速率函数以识别横摆角速率增益。使全部增益相乘以获得最终增益。最终增益被提交给控制模块,该控制模块确定调节从电动助力转向马达输出的扭矩所需的转向扭矩叠加。(A kind of system for correcting the event that pulls round includes input direction disk angle function to identify the steering wheel angle of steering wheel angle gain.By steering wheel speed input direction disk velocity function to identify steering wheel speed gain.By vehicle speed input vehicle speed function to identify vehicle speed gain.By propulsion motor torque input motor torsional moment function to identify propulsion motor torque gain.By Vehicular yaw angular speed input yaw rate function to identify yaw rate gain.Make whole multiplied by gains to obtain final gain.Final gain is submitted to control module, which determines to adjust and be superimposed from steering torque needed for the torque that electric power steering motor exports.)

1. a kind of system for pulling round event for correcting f-w-d vehicle for being superimposed using steering torque, comprising:

For each of steering wheel angle, steering wheel speed, vehicle speed, propulsion motor torque and Vehicular yaw angular speed Determining yield value；

Limit the combined steering torque superposition of all yield values；And

It is exported using the electric power steering motor torsional moment of steering torque superposition modification.

2. system according to claim 1 further includes steering wheel angle function, input has the steering wheel angle, with Identify steering wheel angle gain.

3. system according to claim 2 further includes steering wheel velocity function, input has the steering wheel speed, with Identify steering wheel speed gain.

4. system according to claim 3 further includes vehicle speed function, input has the vehicle speed, with identification Vehicle speed gain.

5. system according to claim 4 further includes motor torsional moment function, input has the propulsion motor torque, with Identify propulsion motor torque gain.

6. system according to claim 5 further includes yaw rate function, input has the Vehicular yaw angle speed Rate, to identify yaw rate gain.

7. system according to claim 1 further includes control module, the control module is configured as receiving described in application The request of steering torque superposition, the control module are sent to the request prioritized and by steering torque superposition Electric power steering motor.

8. system according to claim 1 further includes sensing according to from left wheel rate sensor and right wheel rate The output of device is calculated for wheel rate and the wheel rate gain value of determination.

9. system according to claim 8, wherein passed from the left wheel rate sensor and the right wheel rate The output of sensor is combined and is converted into absolute value in modifier before being entered wheel rate function.

10. a kind of system for pulling round event for correcting f-w-d vehicle for being superimposed using steering torque, comprising:

Steering wheel angle, input direction disk angle function is to identify steering wheel angle gain；

Steering wheel speed, input direction disk velocity function is to identify steering wheel speed gain；

Vehicle speed inputs vehicle speed function to identify vehicle speed gain；

Propulsion motor torque inputs motor torsional moment function to identify propulsion motor torque gain；

Vehicular yaw angular speed inputs yaw rate function to identify yaw rate gain；

Final gain, by making the steering wheel angle gain, the steering wheel speed gain, the vehicle speed gain, institute It states propulsion motor torque gain and the yaw rate multiplied by gains and obtains；And

The control module of the final gain is received, the control module is determined by application to adjust from electric power steering motor The steering torque of the torque of output is superimposed.

Technical field

This disclosure relates to automobile steering system.

Background technique

Drive differential in f-w-d vehicle allows the torque deviation between left and right side to cause in tire and road The different left and right tractive force that face interface generates.Due to internal friction, general open type differential is provided to wheel is driven Unequal torque.Torque is usually biased to slower rotating wheel.The torque deviation of the 10-20% of total torque is considered normal , however, torque deviation generates unbalanced stub steering moment, unbalanced stub steering moment causes to turn in combination Disturbance effect, disturbance effect can be felt as steering force decline by vehicle operator, event is drawn or pulled round to steering wheel.

Pulling round is the unexpected steering event as caused by the inequality between the tractive force on front tyre, most normal Occur under high driving torque, such as when turning acceleration.Since left tire is to right tire traction inequality, driving torque Tend to draw vehicle and steering wheel to turning medial.If steering wheel left and right alternating due to fast-changing loading of tire Ground is stowed, then during the linear accelerating on uneven road also can this thing happens, lead to fast-changing tractive force. Driving torque acts on main shaft as power, generates the stub torque proportional to tractive force and main axis length.Work as driving torque When increasing with tire straight skidding, tire righting moment reduces, so that the phenomenon is more obvious.In addition, by the electricity of electric vehicle The wink hair that drive motor provides is conveyed with high torque so that the effect is more obvious.

Therefore, it although current automobile steering system realizes its expected purpose, needs a kind of new and improves System and method, to compensate in f-w-d vehicle since the different left and rights generated in tire and road surface interface are drawn Disturbance effect is turned to caused by power.

Summary of the invention

It is a kind of to pull round event for being superimposed using steering torque correct f-w-d vehicle according to several aspects System include in steering wheel angle, steering wheel rate, vehicle speed, propulsion motor torque and Vehicular yaw angular speed Each yield value determined.Steering torque superposition is limited by the combination of all yield values.Modification electricity is superimposed using steering torque Dynamic power steering motor torque output.

In another aspect of the present disclosure, the input of steering wheel angle function has steering wheel angle to identify that steering wheel angle increases Benefit.

In another aspect of the present disclosure, the input of steering wheel rate function has steering wheel rate to identify that steering wheel rate increases Benefit.

In another aspect of the present disclosure, the input of vehicle speed function has vehicle speed to identify vehicle speed gain.

In another aspect of the present disclosure, the input of motor torsional moment function has propulsion motor torque to identify that propulsion motor torque increases Benefit.

In another aspect of the present disclosure, the input of yaw rate function has Vehicular yaw angular speed to identify yaw rate Gain.

In another aspect of the present disclosure, electric power steering control module is configured as receiving using steering torque superposition Request, electric power steering control module are sent to electric power steering horse to request prioritized and by steering torque superposition It reaches.

In another aspect of the present disclosure, according to the output meter from left wheel rate sensor and right wheel rate sensor It calculates for wheel rate gain value determined by wheel rate.

In another aspect of the present disclosure, the output from left wheel rate sensor and right wheel rate sensor is combined And absolute value is converted into modifier before being entered wheel rate function.

In another aspect of the present disclosure, the nonlinear function of each function is limited for individual vehicle and drive chain adjustment Shape.

It is a kind of to pull round event for being superimposed using steering torque correct f-w-d vehicle according to several aspects System include the steering wheel angle of input direction disk angle function to identify steering wheel angle gain.Steering wheel speed is inputted Steering wheel velocity function is to identify steering wheel speed gain.Vehicle speed is inputted into vehicle speed function to identify that vehicle speed increases Benefit.By propulsion motor torque input motor torsional moment function to identify propulsion motor torque gain.Vehicular yaw angular speed is inputted Yaw rate function is to identify yaw rate gain.Steering wheel angle gain, steering wheel speed gain, vehicle speed increase Benefit, propulsion motor torque gain and yaw rate gain are recombined to obtain final gain.Final gain is submitted to control Module, the control module determine the steering torque applied superposition to adjust the torque output from electric power steering motor.

Due in tire and road interface in another aspect of the present disclosure, steering torque superposition compensation f-w-d vehicle Locate to turn to disturbance effect caused by the different left tire tractive force and right tire traction generated.

In another aspect of the present disclosure, throttle position, driving torque and vehicle lateral acceleration are respectively in input function To obtain throttle position gain, driving torque gain and vehicle lateral acceleration gain, it is final to determine to input these gains Gain.

In another aspect of the present disclosure, if identification is pulling round event, it is determined whether there is enough turn It can be used for compensating to motor current and pull round event, if it is, when steering torque superposition is sent to steering motor Torque signal changes.

In another aspect of the present disclosure, gain multiplier receives each gain, gain multiplier make all multiplied by gains with Obtain final gain.

In another aspect of the present disclosure, the wheel speed that will be determined from left wheel rate sensor and right wheel rate sensor Rate combines and is converted to absolute value in modifier.

In another aspect of the present disclosure, the output from modifier is entered wheel rate function to generate wheel rate Gain, the gain are passed to gain multiplier.

According to several aspects, a kind of method correcting the event of pulling round using steering torque superposition includes: identification vehicle In due to different left tire tractive force and right tire traction generate pull round event；For steering wheel angle, Each of steering wheel speed, vehicle speed, propulsion motor torque and Vehicular yaw angular speed determine gain；By making to own Multiplied by gains is superimposed to calculate steering torque；By steering torque superimposed layer input control module；And using from control module The torque that is exported from electric power steering motor of Signal Regulation.

In another aspect of the present disclosure, this method is included in input direction disk angle function, steering wheel before calculating step Each of velocity function, vehicle speed function, motor torsional moment function and yaw rate function with identify steering wheel angle, The gain of each of steering wheel speed, vehicle speed, propulsion motor torque and Vehicular yaw angular speed.

In another aspect of the present disclosure, this method includes that can be used for electric power steering motor is identified before regulating step Electric current, to identify whether available current is operable to execute regulating step.

According to description provided herein, other suitable application areas be will become obvious.It should be understood that description and specific The purpose that example is merely to illustrate, it is no intended to limit the scope of the present disclosure.

Detailed description of the invention

Attached drawing described herein is for illustration purposes only, and is not intended to and is limited the scope of the present disclosure in any way.

Fig. 1 is the diagram for pulling round compensation with steering overlapping system according to an exemplary embodiment；

Fig. 2 is the flow chart of the system of Fig. 1；And

Fig. 3 is the curve graph of the exemplary steering torque response of the correction with and without the system for using Fig. 1.

Specific embodiment

It is described below and is substantially merely exemplary, it is no intended to limit the disclosure, application or purposes.

With reference to Fig. 1, multiple signals of vehicles 12, Duo Geche are used using the compensation that pulls round of steering torque overlapping system 10 Signal 12 is input in adjustable function 14 as variable.Turned using the compensation generation that pulls round of steering torque overlapping system 10 It is superimposed to torque, steering torque superposition is for compensating in f-w-d vehicle due to generating not in tire and road surface interface Disturbance effect is turned to caused by same left and right tractive force.Variable as multiple signals of vehicles 12 includes steering wheel angle (SWA) 16, steering wheel speed (SWV) 18, vehicle speed (Vx) 20, propulsion motor torque (Tq) 22, wheel differential 24 and vehicle Yaw rate 26.The supplementary variable that may include in adjustable function 14 includes that throttle position, driving torque and lateral direction of car add Speed.

Steering wheel angle (SWA) 16 is from the received sensing value of steering wheel angle sensor.It is counted according to steering wheel angle 16 Calculate the steering wheel rate (SWV) 18 that unit is degrees second.The vehicle for being thousand ms/h according to the wheel rate calculations unit of measurement Rate (Vx) 20.Unit is that the propulsion motor torque T q 22 of Newton meter is calculated value.Wheel differential 24 is fast according to the wheel of sensing Rate poor (left wheel rate subtracts right wheel rate) calculates and is converted into absolute value, because left and right wheel rate will depend on vehicle It is straight trip or is turning left or turning right and consecutive variations.Unit is that the Vehicular yaw angular speed 26 of degrees second is based on yaw angle The sensing value of the output of rate sensor.As reference Fig. 2 to be more fully described, determines gain and be applied to above-mentioned value Each of.

Output 28 from adjustable function 14 is for calculating steering torque superposition 30.Before steering torque superposition 30 is forwarded to The steering control system 32 of wd vehicle.The torque that steering torque superposition 30 is applied in electric power steering motor 34 is repaired Change, with compensate due in each of left side tire 42 and right side tire 44 tire at road interface generation it is different Disturbance effect caused by left and right tractive force 38,40 at steering wheel 36.

With reference to Fig. 2 and referring again to FIGS. 1, for using steering torque overlapping system 10 pull round compensation can letter of transfer The algorithm of number 14 operates in the following manner.It individually enters and is used as the output inputted from all the sensors and calculated value.It is right Absolute value is applied in several inputs.Then each input is compared with one data in multiple functions, these functions It can be obtained in one or more look-up tables, each look-up table limits the range of the value for an input.It is using function Each input distributes gain.By all multiplied by gains of each input to determine final gain.Final gain is as steering torque The module of compensation request input computer or processor, steering torque compensation request and the received gain of steering system and other Steering torque inputs prioritized together.

As previously mentioned, pulling round is the unexpected steering thing as caused by the inequality between the tractive force on front tyre Part occurs most often under high driving torque, such as when turning acceleration.When influence of tractive force is applied to the power of steering wheel 36 When square, for example, when be driven in left tire or right wheel tire torque it is larger when, pull round event.If identification is being led Draw steering event, then when sending electric powered steering motor 34 for steering torque superposition 30, turn signal changes.

According to several aspects, following five of minimum input is as variable to calculate adjustable function 14.

1) direction is entered from the sensing value for the steering wheel angle 16 that the received unit of steering wheel angle sensor 46 is degree Disk angle function 48, and determine steering wheel angle gain, it is passed to gain multiplier 50.

2) in calculation block 52, list is calculated using the steering wheel angle 16 of unit degree of being on a period of time that unit is the second Position be degrees second steering wheel speed (SWV) 18, and before being inputted steering wheel velocity function 56 by it in modifier 54 In be converted to absolute value.Determine that the gain of steering wheel speed, the gain are passed to gain and multiply according to steering wheel velocity function 56 Musical instruments used in a Buddhist or Taoist mass 50.

3) in calculation block 58, the vehicle speed for being thousand ms/h according to the wheel rate calculations unit of different measurements (Vx) 20, and it is converted into absolute value in modifier 60 before being inputted vehicle speed function 62.According to vehicle speed Rate function 56 determines that the gain of vehicle speed, the gain are passed to gain multiplier 50.

It 4) will be from the sensing of the received practical propulsion motor torque (Tq) 22 of electric power steering motor torsional moment sensor 64 Value input electric power steering motor torsional moment function 66, and determine the gain of electric power steering motor torsional moment, which is passed It is delivered to gain multiplier 50.

It 5) is the Vehicular yaw angular speed 26 of degrees second from 68 recruiting unit of yaw rate sensor, and first by it By filter 70, absolute value then is converted into modifier 72 before being inputted yaw rate function 74. Determine that the gain of yaw rate, the gain are passed to gain multiplier 50 according to yaw rate function 74.

By steering wheel angle, steering wheel speed, vehicle speed, electric power steering motor torsional moment and Vehicular yaw angular speed Each of above-mentioned 5 gains limited are for example combined by making multiplied by gains in gain multiplier 50, to generate most Whole gain 76.Final gain 76 limits steering torque and changes request 78, the electronics resided therein via CAN bus from algorithm Brake control module (EBCM) 80 is sent to electric power steering (EPS) module 82, and is applied to electric power steering horse Up to the torque modification in 34.76 value of final gain is adjustable during system development, and does not hereafter need to be further processed. Algorithm is also adjusted using with those of triggering ability nonlinear function.

Torque is changed all steering system torques requested to system and related traction by electric power steering module 82 Prioritized together is requested in power control.It is final for being limited in electric power steering module 82 based on a series of systematic procedures The priority or permission that gain 76 identifies.It is contemplated that event is pulled round for most of, to electric power steering module 82 Response EBCM Electronic Brake Control Module 78 request with formulate steering torque change request will there is no limit.

The original shape of the nonlinear function of limit value is based on each vehicle in look-up table or function 48,56,62,66 and 74 Pull round event during frequency and system condition and each different drive chain.For example, if traction turns Only occur under high engine torque demand to event, then nonlinear function will be proportional to torque demand.Once defining knowledge The shape of each nonlinear function for the functional value not obtained from look-up table for example, so that it may using interior or CAE adjustment come into One step improves these values.Therefore, the nonlinear function for limiting each function value is adjusted or modifies comprising on it using adjustable Difference between each different vehicle drive chain of function 14, such as to distinguish different vehicle traction torques, braking system mark Standard, wheel rate etc..

Other than above-mentioned five for being used as the input variable for calculating the algorithm of adjustable function 14, for adjustable function 14 Algorithm can also include the wheel rate 84 determined from left wheel rate sensor 86 and right wheel rate sensor 88, left wheel The output of rate sensor 86 and right wheel rate sensor 88 is combined and is repairing before being entered wheel rate function 92 Change in device 90 and is converted into absolute value.Determine that the gain of wheel rate 94, the gain are passed to according to wheel rate function 92 Gain multiplier.The supplementary variable for calculating the algorithm of adjustable function 14 can also include throttle position, driving torque and vehicle Transverse acceleration.Special purpose function is provided for each variable to identify gain associated with each variable.

With reference to Fig. 3 and referring again to Fig. 1 to Fig. 2,96 unit of curve graph is that a period of time upper recognition unit of second is newton The multiple directions disk torque value 98 of rice.First curve 102 indicates that experience is led without using the adjustable function 14 of the disclosure come what is corrected Draw the system of steering event.The torque of first curve 102 deviates part 104 and identifies that maximum steering wheel torque deviates 106 and occurs About 16 seconds.Second curve 108 is substantially Chong Die with the torque value of the first curve 102, deviates part 110 until torque occurs. The excessive-torque for reducing steering system by using adjustable function 14, indicate it is identical pull round the situation of event during, Maximum steering wheel torque in the never correction system of maximum steering wheel torque deviation 112 of second curve 108 deviates 106 and reduces. In the example shown, about 40% reduction of steering torque deviation is realized, however, by utilizing steering torque overlapping system 10 correction for pulling round the steering torque deviation that compensation provides or reduction can change in a range and be expected to be less than 100%.

Due to several, independent of the disclosure pulling round compensation and support using steering torque overlapping system 10 Disappear the 100% of the torque deviation occurred during the event of pulling round.If from the traction using steering torque overlapping system 10 The gain for turning to compensation is submitted to EBCM Electronic Brake Control Module 78 and via CAN bus 80 from EBCM Electronic Brake Control Module 78 It is submitted to electric power steering module 82.It electric power steering module 82 and all steering system torques in system and related leads Draw the priority for controlling request of requesting to be ranked to modify electric power steering motor torsional moment.

The disclosure have the advantages that turn to overlapping system pull round compensation provide it is several.These include providing to be used for Determine that the algorithm of steering torque superposition, the torque that steering torque superposition is applied in electronic-controlled power steering servo-motor are modified, with Compensation compensation due to left different with what is generated at road interface of the tire in each of left side tire and right side tire and Disturbance effect caused by right tractive force at steering wheel.It is used for obtain the output of the adjustable function of data since multiple functions Calculate steering torque superposition.Steering torque is superimposed the steering control system for being forwarded to f-w-d vehicle.

The description of the disclosure is substantially merely exemplary, and the modification for not departing from the purport of the disclosure is intended to fall within this In scope of disclosure.These modifications should not be considered as to disengaging spirit and scope of the present disclosure.