CN103868446B - The steering wheel position testing circuit of electric boosting steering system and detection method thereof - Google Patents
The steering wheel position testing circuit of electric boosting steering system and detection method thereof Download PDFInfo
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- CN103868446B CN103868446B CN201210548294.2A CN201210548294A CN103868446B CN 103868446 B CN103868446 B CN 103868446B CN 201210548294 A CN201210548294 A CN 201210548294A CN 103868446 B CN103868446 B CN 103868446B
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Abstract
This application discloses the steering wheel position testing circuit of a kind of electric boosting steering system, including: torque angle sensor, it is used for obtaining the absolute corner of steering wheel；Rotary transformer, is used for obtaining the corner of assist motor；ECU, gathers the output of torque angle sensor and calculates the absolute corner of steering wheel, also gather the output of rotary transformer and estimate the absolute corner of steering wheel.Once the value of calculation of the absolute corner of steering wheel does not corresponds with estimated value, then ECU abandons this value of calculation, and only uses this estimated value as the absolute corner of steering wheel.The application can solve occurred that burr or edge transition cross the phenomenon such as slow and the inaccurate problem of calculating steering wheel position that causes by the signal of torque angle sensor.
Description
Technical field
The application relates to the electric boosting steering system (Electric Power Steering is called for short EPS) of a kind of automobile,
Particularly relate to steering wheel position testing circuit therein.
Background technology
Referring to Fig. 1, this is the mechanical steering system on automobile.It includes steering wheel 11, steering column 12, steering gear 13, turns
To pull bar 14 and deflecting roller 15.Driver applies steering moment to steering wheel 11, and this steering moment is turned by steering column 12 input
Steering linkage 14 is passed in moment after device 13, the amplification of diverted device 13 and the motion after deceleration, thus drives deflecting roller 15 to move.
Referring to Fig. 2, this is the electric boosting steering system on automobile.It adds on the basis of mechanical steering system:
Torque angle sensor 21, is used for detecting moment of torsion and the corner of steering wheel 11；
Vehicle speed sensor 22, is used for measuring car speed；
ECU (electronic control unit) 23, according to moment of torsion, corner and the GES of steering wheel 11, calculates corresponding
Assist torque, and export to assist motor 24；
Assist motor 24, is arranged in steering column 12 or steering gear 13, and it rotates according to the instruction of ECU 23, thus
Output assist torque；
Reducing gear 25, is converted to steering column 12 or steering gear 13 by the rotational angle of assist motor 24 with certain proportion
Rotational angle.If the speed reducing ratio of reducing gear 25 is k, k ＞ 1, then the rotational angle of assist motor 24/k=steering column 12 turn
Dynamic angle.
The corner of described steering wheel 11 refers to its absolute corner, is not limited by the interval range of 0～360 °.Such as, steering wheel
11 just take two turns relative to 0 ° of position, then absolute position is 720 °.And for example, steering wheel 11 encloses relative to 0 ° of position reversion three,
Then absolute position is-1080 °
Electric boosting steering system is closely related with the driving safety of automobile, and the requirement to reliability is high.
Referring to Fig. 3, the steering wheel position testing circuit of existing electric boosting steering system includes:
Torque angle sensor 21, it is to the signal of the absolute corner of ECU 23 output expression steering wheel 11.
ECU 23, calculates the absolute corner of steering wheel 11 according to the signal of torque angle sensor 21 output.
Referring to Fig. 4, torque angle sensor 21 exports two kinds of angular signals, is the RS signal shown in dotted line and shown in solid respectively
AS signal.Wherein, abscissa is the corner of steering wheel 11, and vertical coordinate is the voltage of each signal.When steering wheel 11 is at-1224 °
In the angle ranges of 1224 °, RS signal is from minimum voltage 0.5V strictly monotone increasing to ceiling voltage 4.5V, and AS signal is altogether
17 second periodicities are had to land vertically as minimum voltage 0.5V from the gradual ceiling voltage 4.5V that rises to of minimum voltage 0.5V again.The week of AS signal
Phase is referred to as angular interval, and the corner of the steering wheel 11 that each angular interval is corresponding is 144 degree.
The method of the corner that ECU 23 calculates steering wheel 11 according to the angular signal of torque angle sensor 21 is:
First, ECU 23, according to the magnitude of voltage of RS signal, learns that AS signal is currently at which angular interval, referred to as AS signal
Initial interval.
Then, ECU 23, according to the relative rotation between the current angular of AS signal and in current angular interval, calculates in real time and turns
To the absolute corner of dish 11.
Specifically, if the amplitude ＞ 2V that the current voltage value of AS signal reduces than last sample voltage value, AS signal is described
The saltus step from ceiling voltage to minimum voltage was there is, then the current interval of AS signal is it in the time interval of double sampling
The interval+1 of last sampling.
If the amplitude ＞ 2V that the current voltage value of AS signal increases than last sample voltage value, illustrate that AS signal is at double sampling
Time interval in there is the saltus step from minimum voltage to ceiling voltage, then the current interval of AS signal is its last sampling
Interval-1.
If amplitude≤2V that the current voltage value of AS signal increases than last sample voltage value or reduces, illustrate that AS signal is two
Do not occurred in the time interval of secondary sampling from the saltus step between minimum voltage and ceiling voltage, then the current interval of AS signal
The interval of sampling is identical with the last time.
The real-time voltage value of AS signal reflects the steering wheel 11 relative rotation in current angular interval.
2V above is the half of the difference of the ceiling voltage 4.5V and minimum voltage 0.5V of AS signal, for preferred value.Should in reality
Other value is may be used without with environment.
In the case of there is signal disturbing, above-mentioned steering wheel position detection method is likely to occur error detection, and this can make electronic
It is (high at vehicle that (making steering wheel 11 can automatically return to straight-line travelling position) and active damping are just being returned in the active of servo steering system
When speed travels, preventing steering wheel 11 from the phenomenon of positive overshoot occurring back) function do not has good effect.
Referring to Fig. 5, this is two cycles of the AS signal that there is interference.Due to signal disturbing so that AS signal occurs in that burr.
Assume that A1, A2 and A3 are three sampled points of AS signal respectively, burr position the most upwards；And the voltage difference of A2 with A1 is big
Voltage difference in 2V, A3 and A2 is less than 2V.Now, ECU 23 can be mistaken for voltage jump by between A1 and A2, causes calculating
The absolute corner of steering wheel 11 increase 144 degree mistakenly.Same, downward burr occurs to adopt in B1, B2 and B3 these three
During sampling point, also result in erroneous judgement.
Referring to Fig. 6, this is two cycles of the AS signal that trailing edge saltus step is delayed excessively.The rising edge gradual change of normal AS signal, and
Trailing edge is in landing vertically.If the saltus step of trailing edge is the slowest, it is assumed that C1, C2 and C3 are three sampled points of AS signal respectively,
The exactly position of trailing edge saltus step；And the voltage difference that the voltage difference of C2 Yu C1 is less than 2V, C3 and C2 is again smaller than 2V.Now, ECU
23 can not have voltage jump by being mistaken for during C1 to C3, cause the absolute corner of the steering wheel 11 calculated to decrease 144 mistakenly
Degree.
Be usually mounted with rotary transformer 241 on existing assist motor 24, be used for obtaining assist motor 24 corner (only with 0～
The interval range of 360 ° represents).This signal exports to ECU 23, for actuating motor control.
Summary of the invention
Technical problems to be solved in this application are to provide the steering wheel position testing circuit of a kind of electric boosting steering system, permissible
Solve to ask owing to AS signal has a burr or trailing edge saltus step is crossed the phenomenon such as slow and caused calculating steering wheel position is inaccurate
Topic.To this end, the application also provides the detection method of described steering wheel position testing circuit.
For solving above-mentioned technical problem, the steering wheel position testing circuit of the application electric boosting steering system includes,
Torque angle sensor, is used for obtaining the absolute corner of steering wheel；
Rotary transformer, is used for obtaining the corner of assist motor；
ECU, gathers the output of torque angle sensor and calculates the absolute corner of steering wheel, also gathers rotary transformer
Export and estimate the absolute corner of steering wheel.
Once the value of calculation of the absolute corner of steering wheel does not corresponds with estimated value, then ECU abandons this value of calculation, and only uses this estimation
It is worth the absolute corner as steering wheel；
The detection method of the steering wheel position testing circuit of described electric boosting steering system is:
ECU gathers the output of torque angle sensor, and calculates the absolute corner of steering wheel；
ECU also gathers the output of rotary transformer, and estimates the absolute corner of steering wheel；
Once the value of calculation of the absolute corner of steering wheel does not corresponds with estimated value, then ECU abandons this value of calculation, and only uses this to estimate
Calculation value is as the absolute corner of steering wheel；
The application uses torque angle sensor to calculate steering wheel angle, uses rotary transformer estimation steering wheel angle, and to two
Individual value compares and monitors with redundancy.Once find that torque angle sensor lost efficacy, switch to turning with rotary transformer estimation
To dish corner, maintain active return function and the active damping function of electric boosting steering system.The program does not increase any hardware
Cost (rotary transformer is originally just to have in assist motor), only just can judge torque angle sensor by the method for software
Abnormal situation occurs, is easy to implement and with low cost.
Accompanying drawing explanation
Fig. 1 is the structural representation of the mechanical steering system on automobile；
Fig. 2 is the structural representation of the electric boosting steering system on automobile；
Fig. 3 is the structural representation of the steering wheel position testing circuit of existing electric boosting steering system；
Fig. 4 is the principle schematic of the steering wheel angle signal of existing torque angle sensor output；
Fig. 5 is the schematic diagram of the AS signal that there is interference；
Fig. 6 is the schematic diagram of the AS signal that trailing edge saltus step is delayed excessively；
Fig. 7 is the structural representation of the steering wheel position testing circuit of the application electric boosting steering system；
Fig. 8 is the detection method flow chart of the steering wheel position testing circuit of the application electric boosting steering system.
Description of reference numerals in figure:
11 is steering wheel；12 is steering column；13 is steering gear；14 is steering linkage；15 is deflecting roller；21 is torque axis
Angle transducer；22 is vehicle speed sensor；23 is ECU；24 is assist motor；241 is rotary transformer；25 is reducing gear.
Detailed description of the invention
Referring to Fig. 7, the steering wheel position testing circuit of the electric boosting steering system of the application includes:
Torque angle sensor 21, represents RS signal and the AS signal of the absolute corner of steering wheel 11 to ECU 23 output.Institute
State RS signal in the range of the hard-over of steering wheel 11, on the corner direction from small to large of steering wheel 11, from minimum voltage
In strictly monotone increasing to ceiling voltage.Described AS signal presents cyclically-varying in the range of the hard-over of steering wheel 11,
On the corner of steering wheel 11 direction from small to large, in each cycle before this from minimum voltage strictly monotone increasing to ceiling voltage again
Land vertically as minimum voltage.
Rotary transformer 241, is arranged on assist motor 24, is used for obtaining the anglec of rotation of assist motor 24.
ECU 23, the RS signal of collection torque angle sensor 21 output and AS signal also calculate definitely turning of steering wheel 11
Angle, also gathers the output of rotary transformer 241 and estimates the absolute corner of steering wheel 11.
Once the value of calculation of the absolute corner of steering wheel 11 does not corresponds with estimated value, then ECU 23 abandons value of calculation, and only uses and estimate
Calculation value is as the absolute corner of steering wheel 11.
Referring to Fig. 8, the detection method of the steering wheel position testing circuit of described electric boosting steering system is:
ECU 23 gathers RS signal and the AS signal of torque angle sensor 21 output, and calculates the absolute corner of steering wheel 11；
ECU 23 also gathers the output of rotary transformer 241 and estimates the absolute corner of steering wheel 11；
Once the value of calculation of the absolute corner of steering wheel 11 does not corresponds with estimated value, then ECU 23 abandons value of calculation, and only uses and estimate
Calculation value is as the absolute corner of steering wheel 11.
The method of the absolute corner that described ECU 23 calculates steering wheel 11 is situated between in detail at the description of the present application background section
Continue, repeat no more.Preferably, it may be judged whether the threshold values of saltus step between minimum voltage and ceiling voltage occurred, can be set to the highest
The half of the difference of voltage and minimum voltage.Obtained by steering wheel 11 absolute corner value of calculation can by signal disturbing, under
Drop to cross along saltus step and slow wait impact and inaccurate.
Described ECU 23 estimates that the method for the absolute corner of steering wheel 11 is:
First, ECU 23 obtains the corner of assist motor 24 according to the output of rotary transformer 241.Such as, rotary transformer 241
Output represents the analogue signal of the corner of assist motor 24, after ECU 23 decodes it as digital signal, can directly obtain power-assisted
The corner (being limited with the interval range of 0～360 °) of motor 24.
Then, the corner of assist motor 24 is estimated the absolute corner of steering wheel 11 by ECU.The speed reducing ratio assuming reducing gear 25 is
K, k ＞ 1.When assist motor 24 rotates, steering wheel 11 also can correspondingly rotate divided by k times of ground.When steering wheel 11 rotates,
Assist motor 24 also can correspondingly be multiplied by k times of ground and rotate.Such as, k=20, then assist motor 24 often turns over 360 degree, steering wheel 11
Only turn over 12 degree.
If assist motor when the difference ＞ Second Threshold of front hook value with last sampling corner value, then the angle of rotation of steering wheel
Degree=(corner of assist motor-360 °)/k；
If assist motor when the difference ＜-1* Second Threshold of front hook value with last sampling corner value, then the rotation of steering wheel
Angle=(corner of assist motor+360 °)/k；
If the difference≤Second Threshold when front hook value and last sampling corner value of assist motor and >=-1* Second Threshold, then
Corner/the k of the rotational angle=assist motor of steering wheel；
The span of described Second Threshold is: 0 ＜ Second Threshold ＜ 360 °.Preferably, Second Threshold can be set to 300,
Actual application can also be set to other value.
The angle of rotation of steering wheel 11 of the initial corner of the absolute corner of steering wheel 11=a certain moment steering wheel 11+since this moment
Degree.The initial corner of described a certain moment steering wheel 11 is calculated by torque angle sensor 21.
Preferably, ECU 23 compares the value of calculation of absolute corner of steering wheel 11 and the method for estimated value is: take the exhausted of both differences
To value, after being more than a fixing threshold values such as this absolute value and exceed the regular hour, then it is assumed that torque angle sensor 21 is right
The corner monitoring of steering wheel 11 was lost efficacy, and only with the estimated value obtained by rotary transformer 241.Described exceed the regular hour can
Monitored by enumerator.
These are only the preferred embodiment of the application, be not used to limit the application.For a person skilled in the art, originally
Application can have various modifications and variations.All within spirit herein and principle, any amendment of being made, equivalent,
Improve, within should be included in the protection domain of the application.
Claims (3)
1. a detection method for the steering wheel position testing circuit of electric boosting steering system, the method is electric boosted for one
The steering wheel position testing circuit of steering, this circuit includes: torque angle sensor, is used for obtaining definitely turning of steering wheel
Angle, and export two kinds of signals representing the absolute corner of steering wheel, it is RS signal and AS signal respectively；Described RS signal is turning to
It is that strictly monotone increasing is to ceiling voltage in steering wheel angle direction from small to large from minimum voltage in the range of the hard-over of dish；
Described AS signal presents cyclically-varying in the range of the hard-over of steering wheel, each in steering wheel angle direction from small to large
Cycle lands vertically as minimum voltage before this from minimum voltage strictly monotone increasing to ceiling voltage again；Rotary transformer, is used for obtaining
The corner of assist motor；
The feature of the detection method of the steering wheel position testing circuit of described electric boosting steering system is,
ECU, i.e. electronic control unit, gather the output of torque angle sensor, and calculate the absolute corner of steering wheel；
ECU also gathers the output of rotary transformer, and estimates the absolute corner of steering wheel；
Once the value of calculation of the absolute corner of steering wheel does not corresponds with estimated value, then ECU abandons this value of calculation, and only uses this estimation
It is worth the absolute corner as steering wheel；
The method of the absolute corner that described ECU calculates steering wheel is:
First, according to the magnitude of voltage of RS signal, learn which cycle AS signal is currently at, be referred to as it the most interval；
Then, by the current interval of AS signal and the relative rotation in current interval, the absolute corner of steering wheel is obtained；
If the amplitude ＞ first threshold that the current voltage value of AS signal reduces than last sample voltage value, then AS signal is current
Interval is that interval during last time sampling adds 1；
If the amplitude ＞ first threshold that the current voltage value of AS signal increases than last sample voltage value, then AS signal is current
Interval is that interval during last time sampling subtracts 1；
If the current voltage value of AS signal is than last sample voltage value amplitude of variation≤first threshold, then AS signal work as proparea
Between interval when sampling with the last time keep constant；
AS signal relative rotation in current interval is obtained by its real-time magnitude of voltage；
Described first threshold is the maximum voltage value half with the difference of minimum voltage value of AS signal.
The detection method of the steering wheel position testing circuit of electric boosting steering system the most according to claim 1, its feature
It is that the method for the absolute corner of described ECU estimation steering wheel is:
First, the corner of assist motor is obtained according to the output of rotary transformer；
Then, the corner of assist motor is estimated the absolute corner of steering wheel；
If assist motor when the difference ＞ Second Threshold of front hook value with last sampling corner value, then the angle of rotation of steering wheel
Degree=(corner of assist motor-360 °)/k；
If assist motor when the difference ＜-1* Second Threshold of front hook value with last sampling corner value, then the rotation of steering wheel
Angle=(corner of assist motor+360 °)/k；
If assist motor when the difference≤Second Threshold of front hook value with last sampling corner value, and assist motor work as forward
Angle value and the difference >=-1* Second Threshold of last sampling corner value, then the corner/k of the rotational angle=assist motor of steering wheel；
Wherein k is the speed reducing ratio of reducing gear, k ＞ 1；0 ＜ Second Threshold ＜ 360 °；
The rotational angle of steering wheel of the initial corner of the absolute corner of steering wheel=a certain moment steering wheel+since this moment.
The detection method of the steering wheel position testing circuit of electric boosting steering system the most according to claim 2, its feature
It is that described Second Threshold is 300 °.
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Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105320121B (en) * | 2014-07-16 | 2018-02-23 | 联创汽车电子有限公司 | Electric power steering safety monitoring system |
| CN105915127A (en) * | 2016-06-01 | 2016-08-31 | 同济大学 | Motor rotor position redundant measuring method and system and electronic device |
| CN106697039B (en) * | 2016-11-23 | 2018-11-09 | 耐世特汽车系统（苏州）有限公司 | It is a kind of based on the active rotary transform tensor system for having brush electric boosting steering system |
| CN106839970B (en) * | 2017-02-23 | 2018-01-19 | 吉林大学 | A kind of steering wheel angle measurement apparatus and method for driving data acquisition system |
| CN109987135B (en) * | 2017-12-29 | 2022-05-06 | 陕西重型汽车有限公司 | Steering system for heavy vehicle |
| CN109579676B (en) * | 2018-11-26 | 2020-12-25 | 南京长峰航天电子科技有限公司 | Position decoding method and system based on phase loss lock of dual-channel rotary transformer |
| CN110435668B (en) * | 2019-06-26 | 2021-08-24 | 驭势科技（北京）有限公司 | Failure detection method and module for intelligent driving vehicle actuating mechanism and vehicle-mounted equipment |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101377453A (en) * | 2007-08-31 | 2009-03-04 | 同济大学 | Electric loading test device and method for automobile steering system |
| CN101472783A (en) * | 2006-06-22 | 2009-07-01 | Zf腓特烈港股份公司 | Method and device for determining a steering angle |
| CN101480967A (en) * | 2008-01-09 | 2009-07-15 | 株式会社电装 | Steering system for vehicle |
| CN102035457A (en) * | 2009-10-02 | 2011-04-27 | 欧姆龙汽车电子株式会社 | Motor drive device |
| CN102582678A (en) * | 2011-01-11 | 2012-07-18 | 上海联盛汽车电子有限公司 | Electric power-assisted steering system with software integrated monitoring function |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4728406B2 (en) * | 2009-01-07 | 2011-07-20 | 本田技研工業株式会社 | Electric power steering device |
-
2012
- 2012-12-17 CN CN201210548294.2A patent/CN103868446B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101472783A (en) * | 2006-06-22 | 2009-07-01 | Zf腓特烈港股份公司 | Method and device for determining a steering angle |
| CN101377453A (en) * | 2007-08-31 | 2009-03-04 | 同济大学 | Electric loading test device and method for automobile steering system |
| CN101480967A (en) * | 2008-01-09 | 2009-07-15 | 株式会社电装 | Steering system for vehicle |
| CN102035457A (en) * | 2009-10-02 | 2011-04-27 | 欧姆龙汽车电子株式会社 | Motor drive device |
| CN102582678A (en) * | 2011-01-11 | 2012-07-18 | 上海联盛汽车电子有限公司 | Electric power-assisted steering system with software integrated monitoring function |
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