KR20100114993A - Turning velocity sensor offset correction method in vehicle - Google Patents

Abstract

PURPOSE: A method for correcting turning speed sensor offset of a car is provided to realize the ESC control more accurately than the natural control flow without area which flicks between applied models. CONSTITUTION: A method for correcting turning speed sensor offset of a car is an order offset correction in successively correction method of offset value considering the turning speed. And uses an offset correction algorithm based on model applying the car dynamics equation which use the sped or steering angle as an input element. After calculating the correction value of turning speed senor offset, weight value is given to output element p,q,r at the same which divides the speed and steering angle into specific area. And applies the integration fuzzy logic correction algorithm which calculates the correction value of the precalculated turning speed sensor offset with a average correction value Ψ. Therefore, the optimum turning speed sensor offset correction algorithm which continues the floe without flicking over the boundary is realized.

Description

Turning velocity sensor offset correction method in vehicle

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to turning control of a vehicle, and more particularly to a turning speed sensor offset correction method of a vehicle.

In general, the turning control of the vehicle is implemented based on the information of the turning speed sensor that measures the rotational angular velocity.

Although the basic information is provided by using the turning speed sensor during the turning control, the sensor has a disadvantage in that Off Set, which is an electric drift phenomenon, is generated in measuring the value of the sensor.

For this reason, during the turning control, an offset sensor is corrected to obtain an accurate sensor value and to control the ESC more accurately. Such offset correction is performed in various ways.

For example, you can use the BF (Butterworth Filter) and the CF (Chebychev Filter) to correct the offset, or use the auxiliary Thermal Sensor to create a look-up table. In this case, a method of correcting an offset through a process of feedback is applied.

However, the above-described offset correction method also has disadvantages. In the method using the Butterworth Filter (BF) and the Chebychev Filter (CF), a large distortion may occur at the time of the offset generation and the end point. In addition, the measurement of the sensor value has a disadvantage that a larger error may occur.

In addition, in the case of a method of creating a look-up table using an auxiliary temperature sensor and correcting an offset through a feedback process, a temperature sensor additionally added Due to the cost increases.

Accordingly, the present invention has been invented in view of the above, and calculates an offset correction value of a software speed sensor using a sequential offset correction method based on a vehicle dynamics model-based correction method, and calculates an offset correction value calculated. It is an object of the present invention to provide an offset correction method that can implement a continuous control flow without a bouncing area between applied models by applying fuzzy logic individually or mixed with each other in consideration of a vehicle driving state.

In addition, since the rotation speed sensor offset correction method does not use a filter or a temperature sensor that is additional hardware, more accurate turning control can be realized without a cost increase without fear of error. It also has a purpose.

In order to achieve the above object, the present invention relates to a method for correcting a turning speed sensor offset of a vehicle, wherein a minimum resolution in which the vehicle dependency degree Vx and the steering wheel angle δswA are reference values at a turning driving time of the vehicle. For Vx, res and δswA, res│, a satisfactory state (Case 1) and 0 are satisfied according to the condition of 0 <Vx <Vx, res and 0 <| A correction mode determination step of determining the excess b state (Case 2);

If the state a (Case 1) satisfies 0 < Vx < Vx, res and 0 & lt ^; _mean (measured turning speed value of the vehicle speed sensor)-ψ ^. _{temp, offset} (temporary offset value initialized to 0) = ψ ^. After temporarily calculating _comp (temporary offset correction value), the ψ ^. offset value according to the magnitude value of 0 of _comp ^. _{Find the offsets} sequentially, then ψ ^. _mean -ψ ^. _offset = ψ ^. calculating a _comp (finally corrected revolution speed value) and applying a sequential offset correction algorithm to repeat this process with a constant loop time;

The b state (Case 2) does not satisfy the a state (Case 1), but simultaneously satisfies │ δswA, res│ <│δswA │ <│δswA, ss│ with the conditions Vx, res <Vx <Vx, ss Ψ calculated in the a state (Case 1) ^. Calculated current turning vehicle speed ψ, with _comp ^. _{ws, dynamics} = (Vl-Vr) / 2Cf and the measured sensor turning speed value ψ ^. using _mean , ψ ^. _offset [offset correction value] [ψ ^. _{offset = w (s) (ψ} mean -.. ψ ws, dynamics)] to obtain, ^ψ. _comp1 (finally corrected revolution speed value) = ψ ^. _mean -ψ ^. Perform a first model-based offset correction algorithm for recalculating the _offset , and use the steering angle sensor measurement to drive the current turning vehicle speed ψ ^. _{swA, dynamics} [ψ ^. _{swA, dynamics} = (Vx * δRw) / {[V ² x /) g / kund)] + lf + lr}] and the measured sensor turning speed value ψ ^. using _mean , ψ ^. _offset2 (offset correction value) [ψ ^. _offset = w (s) (ψ ^. _mean -ψ ^. _{swA, dynamics} )] ^. _comp2 (finally corrected revolution speed value) = ψ ^. _mean -ψ ^. _After performing a second model-based offset correction algorithm to obtain the _offset again, ψ ^. _comp and ψ ^. _comp1 and ψ ^. _sum all _comp2 and mean value ψ ^. applying an average offset correction algorithm to repeat the process of calculating _{comp, ave} with a constant loop time;

The input element Vx is divided into Vxslow, Vxmedium, Vxfast and Vxveryfast for the speed difference, and the input element δswA is divided into δswAsmall, δswAmedium, δswAlarge and δswAverylarge for the steering angle, and then a weighting factor is given. The output element p, q, r is applied to one of the output elements of p, q or r, depending on the control state ^. _comp and ψ ^. _comp1 and ψ ^. _{sum comp2} and take the p, q, and r above into the average correction value ^. Applying an integrated fuzzy logic correction algorithm that obtains and applies the offset correction value of the speed sensor; Characterized in that performed.

The sequential offset correction algorithm is a temporary offset value ψ ^. After initializing _{temp, offset} value to 0, ψ ^. _{temp, offset} -ψ ^. _mean = ψ ^. After calculating _comp

Calculated ψ ^. _{If comp} is greater than 0, n _YOR values are added by 1, but the calculated ψ ^. _{If comp} is equal to or less than 0, the process of subtracting the n _YOR value by 1 is repeated ^. If the value of n _YOR is greater than the value of N _counter, ψ ^. _offset to Δψ ^. _ss is added, or if n _YOR is less than -N _counter value, then ψ ^. _offset to Δψ ^. _After subtracting by the value of _ss , while initializing the n _YOR value to 0, ψ ^. _After calculating the _offset

ψ ^. _mean -ψ ^. _offset = ψ ^. _{This is} performed by a procedure for calculating _{comp (} finally corrected turning speed value).

_{Ψ when} the n _YOR value is between −N _counter values and N _counter values ^. _{Since offset} is 0, the offset value is not corrected.

In the step of applying the average offset correction algorithm, when the vehicle dependency degree Vx does not exceed Vx, ss and the steering wheel angle │ δswA │ does not exceed │δswA, ss│ If the dependence degree of Vx exceeds Vx, ss and the steering wheel angle │ δswA │ is greater than │ δswA, ss│, it is determined that the vehicle is out of the steady-state. Control is performed without correcting the value.

Ψ ^. To calculate ψ ^. _comp- > ψ ^. _{case 1} , ψ ^. _comp1- > ψ ^. _case2 , ψ ^. _comp2- > ψ ^. ψ for an output element p substituted with _case3 and given the weighting factor ^{. _{= [(P * ψ. Case1}} ) + (ψ. Case2 + ψ. Case3)] calculated by the / p + q + r, and

Ψ for the output element q given the weighting factor ^. = [ψ ^{. _{case1 + (q * ψ. case2}} ) + ψ. calculated as _case3 ] / p + q + r,

Ψ for the output element r given the weighting factor ^{. _{= [(Ψ. Case1 + ψ}} . Case2) + r * ψ. _case3 ] / p + q + r.

According to the present invention, after calculating a variety of software correction value for the turning speed sensor offset (Offset), the fuzzy offset value calculated in accordance with the vehicle driving conditions in a separate manner or mixed purge Since it is performed with (Fuzzy) logic, there is a natural control flow without bouncing between applied models and more accurate ESC control.

In addition, since the present invention does not use a hardware such as a filter or a separate temperature sensor in the correction control for the turning speed sensor offset, there is no burden such as measurement error and cost increase. Have

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Since the exemplary embodiments of the present invention may be embodied in various different forms, one of ordinary skill in the art to which the present invention pertains may be described herein. It is not limited to the Example to make.

1 is a flowchart and calculation equations for a method for correcting a turning speed sensor offset of a vehicle according to the present invention. The present invention provides a speed and a steering angle of a driving vehicle to correct a turning speed sensor offset. After determining, by applying a fuzzy logic according to the area of the speed value and the steering angle value, it is implemented in an optimal manner according to the driving state of the vehicle.

More specifically, whether to apply a sequential offset correction method having an algorithm that corrects the offset value sequentially after considering the turning speed of the vehicle, and various model-based offsets together with the sequential offset correction method. (Offset) Determine whether to apply the correction method at the same time.

When the application method is determined as described above, a fuzzy logic that gives weighting factor to the output according to the input condition is applied again, which is beyond the application area between the correction models selected by the application of the fuzzy logic. There is no bouncing area on the go, which results in an optimal offset correction algorithm that naturally leads to a continuous control flow.

To this end, in this embodiment, the offset calculation process according to the vehicle condition is implemented first.

The sequential offset correction scheme in the above offset calculation process is shown in FIG. 1, which is a temporary offset value ψ ^. After initializing the _{temp and offset} values to 0 _{, the offset of} the driving vehicle measured by the sensor ψ ^. ψ in _mean value ^. minus the _{temp, offset} values, and the difference between them is ψ ^. _{Computes the comp} value.

Then, the calculated ψ ^. If the value _comp value is greater than zero but in addition the n _YOR value by one, the computed ^ψ. _{If the comp} value is less than or equal to 0, the n _YOR value is subtracted by one.

_Ψ is repeated when n _YOR value is larger than N _counter value ^. _offset value is Δψ ^. _By adding _ss value and repeating this process, n _YOR value determines the initialization of n _YOR value according to N _counter value.

In the present embodiment, if the n _YOR value is greater than the N _counter value, ψ ^. _offset value is Δψ ^. _ss is added, and if the value of n _YOR is less than -N _counter value, ψ ^. _offset value is Δψ ^. Subtract _ss value and initialize n _YOR value to 0.

However, if the n _YOR value is between-N _counter value and N _counter value, ψ ^. _{Since the offset} value becomes 0, the _offset value is not corrected at this time.

2 (b) shows N _counter and Δψ ^. _Represents design parameters such as _ss .

Ψ determined as calculated above ^. _offset value and ψ measured at the sensor ^. _{When the} difference between the _mean values is obtained, the final corrected turning speed value ψ ^. _comp value, expressed as follows:

ψ ^. _comp = ψ ^. _mean -ψ ^. _offset -------- (A)

The algorithm having the above-described process continuously performs repeatedly with a constant loop time.

However, the model-based offset correction scheme using vehicle dynamics has a different algorithm from the above scheme.

That is, the model-based offset correction method using vehicle dynamics first obtains the turning speed using the vehicle dynamics, and then uses the corrected turning speed value ψ ^. _By obtaining a _comp value, this is largely classified into a first and second model based offset correction scheme.

Referring to FIG. 1, the first model-based offset correction scheme applies the following vehicle dynamic revolution speed equation in which vehicle wheel speed is a function.

ψ ^. _{ws, dynamics} = (Vl-Vr) / 2Cf-(1)

Here, Vl and Vr represent the left and right wheel speeds of the non-drive shaft in the two-wheel drive vehicle.

Then, the sensor turning speed value ψ measured using a sensor mounted on the vehicle ^. _After calculating the _mean , the sensor revolution speed value ψ ^. ψ computed from _mean and vehicle dynamics speed equation (1) ^. _ws, by applying the _dynamics of the following offset calculation equation ^ψ. Calculate the _offset

ψ ^. _offset = w (s) (ψ ^. _mean -ψ ^. _{ws, dynamics} )-(2)

Here, w (s) is a low pass filter having a form of 1 / (τs + 1), which is ψ ^. This is to filter the _offset value.

Ψ as above ^. ψ, which is the value of the corrected turning speed after the _offset value is calculated ^. Finally, the _comp value is obtained. For this, the following equation is applied.

ψ ^. _comp = ψ ^. _mean -ψ ^. _offset -------- (A)

As can be seen from the above equation (A), the finally corrected revolution speed value ψ ^. _comp is the ψ measured at the sensor ^. _mean and ψ ^. _{This is} determined by the difference between the _offsets .

On the other hand, compared to the first model-based offset correction method using the dynamic equation as described above, the second model-based offset correction method also applies the vehicle dynamics rotational speed equation, but the steering angle as shown in the following equation It is calculated using sensor measurement value.

ψ ^. _{swA, dynamics} = (Vx * δRw) / {(V ² x /) g / kund)] + lf + lr}-(1 ')

Here, the Vx is measured by the wheel speed sensor, which is a method of measuring the angle using the distance from one point of the tooth to one point of the other tooth, lf, lr is the distance between the teeth of the left and right wheels, respectively. .

In addition to applying the above equation, the sensor turning speed value ψ measured using a vehicle mounted sensor ^. _After calculating the _mean , the sensor revolution speed value ψ ^. ψ calculated from _mean and vehicle dynamics speed equation (1 ') ^. _swA, by applying the _dynamics of the following offset calculation equation ^ψ. Calculate the _offset

ψ ^. _offset = w (s) (ψ ^. _mean -ψ ^. _{swA, dynamics} )-(2 ')

Here, w (s) is a low pass filter having a form of 1 / (τs + 1), which is ψ ^. This is to filter the _offset value.

Thus ψ ^. _{After the offset} value is calculated, the corrected revolution speed value ψ ^. Finally, the _comp value is obtained. For this, the following equation is applied.

ψ ^. _comp = ψ ^. _mean -ψ ^. _offset -------- (A)

As can be seen from the above equation (A), the finally corrected revolution speed value ψ ^. _comp is the ψ measured at the sensor ^. _mean and ψ ^. _{This is} determined by the difference between the _offsets .

As described, ψ is the value of the revolution speed corrected by applying each method ^. After the final _comp value is calculated, the ψ ^. Determine how _comp values are applied.

Figure 2 (a) is the ψ ^. Here is an example of how _comp is applied:

As described above, in the present embodiment, after dividing into two cases based on the control point state of the driving vehicle, a sequential offset correction model or a first and second model based offset correction model is applied. Or control by applying a mixture of calibration models.

In addition, in the present embodiment, the fuzzy logic is performed at the step of crossing the boundary between the models in which the respective application areas exist as described above, and the application of the fuzzy logic is a natural control without the bouncing area between the models. At the same time with the flow, ESC control can be more accurately implemented.

When the sequential offset correction model is applied during the control to which the model is applied, the following conditions are applied.

In Fig. 2 (a), a state (Case 1) is a case where a sequential offset correction model is applied, which means that the steering wheel angle δswA is satisfied while the vehicle dependency degree Vx satisfies 0 <Vx <Vx, res. It is time to satisfy the condition that 0 <δswA <δswA, res.

That is, it is due to the inaccuracy of Vl, Vr, δRw, lf and lr which are the vehicle parameters described in FIG. .

In this case, Vx, res and δswA, res│ are minimum resolutions that are reference values for Vx and δswA.

Resolution is applied to the sensor that measures the angle using the distance from one point of the tooth to one point of the other tooth. The minimum resolution as described above is the same for two points where the angle measurement is impossible. When in the tooth, it means the minimum reference to enable the value to be considered in consideration of this, for example, in Figure 2 (a) means a boundary value of the a state (Case 1) and b state (Case 2).

3 shows an algorithm of the sequential offset correction model.

The temporary offset value ψ as described above ^. _{temp, offset} value ψ ^. _After initializing _{temp, offset} = 0, offset correction value ψ ^. _{Compute comp}

Offset correction value ^. _comp = ψ ^. _mean (sensor measurement turning speed value)-ψ ^. _{temp, offset} (temporary offset value)

As a result, the ψ ^. _{If the} value of _comp is greater than 0, 1 is added to calculate n _YOR , but the ψ ^. _{If comp} is less than 0, subtract 1 to calculate n _YOR .

Ψ based on the value of N _counter when repeating the above calculation process ^. to change the _offset value, which is greater than the value n _YOR N _counter value (n _YOR> N _counter) if ^ψ. increasing the _offset value, but, on the contrary, if the value of n _YOR flew less than the _counter value N at the same time n is less _YOR (n _YOR <-N _counter) -N than _counter ^ψ. Decreases the _offset value.

Ψ calculated after operation ^. _offset is the ψ measured by the sensor ^. Considering the _mean , ψ, which is a value of revolution speed corrected using the equation (A) described above ^. finally _comp .

ψ ^. _comp = ψ ^. _mean -ψ ^. _offset -------- (A)

Ψ ^. _comp is determined by the offset correction value for the speed sensor, and ψ ^. _{The comp} calculation is repeated with a constant loop time until the turn is complete.

Ψ calculated by the sequential offset correction method model ^. Although the control of the a state (Case 1) may be performed using _comp , in the present embodiment, the ψ ^. Fuzzy logic with different control factors applied to _comp is performed, which is ψ through b state (Case 2) of FIG ^. _The same applies to _comp , which will be described later.

Meanwhile, since the b state (Case 2) of FIG. 2A includes the a state (Case 1), both the first and second model-based offset correction methods as well as the sequential offset correction model are included. Apply

That is, ψ as a sequential offset correction algorithm ^. seeking _comp, also the first and second model based on the offset (Offset) correction algorithm as ^ψ. _{After comp} is obtained, these three ψ ^. The average value of _comp is offset offset value ψ ^. _Compute with _comp

4 is an algorithm for the b state (Case 2) as described above, which means that the steering wheel angle │ δswA │ is δδswA, res│ As a condition that satisfies < δswA │ <│swsw, ss│, the intermediate value is calculated by applying both the sequential offset correction model and the first and second model-based offset correction model.

At this time, the criteria for determining whether the vehicle is in a steady-state are Vx, ss and | δswA, ss |, where Vx, ss and |

In case of the b state (Case 2), it is possible to measure the sensor value because Vx and δswA │ are larger than Vx, res and │δswA, res│ which are the minimum resolution of the sensor. This is due to the possibility of application.

Subsequently, the sequential offset correction algorithm described above is omitted, and the first and second model-based offset correction algorithms will be described.

The first model-based offset correction algorithm is a current turning vehicle speed ψ using a dynamic equation of the vehicle ^. Calculation of _{ws, dynamics} (ψ ^. _{ws, dynamics} = (Vl-Vr) / 2Cf), and sensor revolution speed ψ measured at the sensor ^. After calculating the _mean , these values are used to offset offset value ψ ^. _offset [ψ ^. _offset = w (s) (ψ ^. _mean -ψ ^. _{ws, dynamics} )].

Ψ calculated as above ^. _offset and ψ ^. through _mean ψ ^. yields _comp , which is ψ ^. _comp = ψ ^. _mean -ψ ^. _{like offset} ^. _offset and ψ ^. ψ, which is the corrected turning speed value of the first model-based offset correction algorithm by subtracting the _mean values from each other ^. Finally, the _comp value is calculated.

In addition, ψ which is the final corrected turning speed value through the second model based offset correction algorithm ^. _comp applies the following procedure:

That is, the current turning vehicle speed ψ using the steering angle sensor measurement in the vehicle dynamics turning speed equation ^. _{Calculate swA, dynamics} as

ψ ^. _{swA, dynamics} = (Vx * δRw) / {(V ² x /) g / kund)] + lf + lr}

In addition, the sensor turning speed value ψ ^. _{The mean is} also calculated.

With ψ ^. _{swA, dynamics} and ψ ^. offset value using _mean ^. _{The offset} is calculated as follows.

ψ ^. _offset = w (s) (ψ ^. _mean -ψ ^. _{swA, dynamics} )

The offset value ^. The calculation of _offset applies a low pass filter for filtering.

Thus ψ ^. _mean and ψ ^. Once all of the _offsets have been calculated, the final revised revolution speed value ψ ^. yields _comp , which is ψ ^. _comp = ψ ^. _mean -ψ ^. Apply _offset

Then, all the calculated values, i ^. _comp (sequential offset calculation) and ψ ^. _comp (first model based offset calculation) and ψ ^. sum all _comp (the second model based offset calculation), and then average them ψ ^. _{comp, ave} , and ψ ^. _{comp, ave} is determined by the offset correction value for the speed sensor, as described above ^. _{The comp and ave} calculations are repeated with a constant loop time until the turn is complete.

Ψ as above ^. _{Comp, ave} can be used to control the b state (Case 2), but in the present embodiment, the ψ ^. Perform fuzzy logic with different control arguments to _{comp and ave} .

When the b state is exceeded as described above, offset correction is not performed. When the first and second model-based offset correction algorithms are applied, the vehicle dependency degree Vx exceeds Vx, ss and the steering angle │ δswA If the value is larger than δswA, ss, the vehicle is out of the Steady-State. Therefore, the vehicle is controlled without correcting the offset value.

Then, the fuzzy logic, which is implemented in the present embodiment and obtains an offset correction value that is actually applied, calculates a sequential offset ψ of a state (Case 1) ^. First model based offset calculation of the _comp and b states (Case 2) ^. _comp1 and the second model based offset calculation ^. _The same applies to _comp2 , so they are explained together, ψ ^. _comp- > ψ ^. _{case 1} , ψ ^. _comp1- > ψ ^. _case2 , ψ ^. _comp2- > ψ ^. _Substitute with _case3 to explain.

When performing the fuzzy logic as described above, ψ which is the average value of the offset calculated ^. _case1 ,, ψ ^. _case2 , ψ ^. _{In case3} , the input elements Vx and δswA are applied to each of the control areas which are classified in detail.

FIG. 5 shows this. Thus, Vx is divided into Vxslow, Vxmedium, Vxfast, and Vxveryfast for the vehicle speed difference, and δswA is divided into δswAsmall, δswAmedium, δswAlarge, and δswAverylarge for the steering angle difference.

Ψ which is an offset correction value calculated by subdividing Vx and δswA as described above ^. _{case 1} , ψ ^. _case2 , ψ ^. The output elements p, q, and r are assigned to _{case 3} with weighting factors.

The sum of p, q, and r satisfies p + q + r = 1, for example, p = 0.3, q = 0.4, r = 0.3, but may be variously applied at a ratio of 1. .

The application of p, q, and r is applied individually according to each case, that is, sequential offset calculation according to a state (Case 1) ^. _Case1 and the first model based offset calculation of the b state (Case 2) ψ ^. _case2 and the second model based offset calculation of the b state (Case 2) ψ ^. _{After case3} was individually applied to p, q and r, the final corrected revolution speed value ψ ^. Is calculated and then the calculated ψ ^. Is determined as the offset correction value of the speed sensor.

This is illustrated in FIG. 5. For example, when the output element p given the weighting factor is the main control element, ψ ^{. _{= [(P * ψ. Case1}} ) + (ψ. Case2 + ψ. Case3)] / p + q + r calculated by, and thus calculates ^ψ. Is applied as the offset correction value of the speed sensor to control when turning.

In the case where the output element q to which the weighting factor is given is the main control element, ψ ^. = [ψ ^{. _{case1 + (q * ψ. case2}} ) + ψ. ψ calculated as _case3 ] / p + q + r and thus calculated ^. Is applied as the offset correction value of the speed sensor to control when turning.

In addition, when the output element r given the weighting factor is the main control element, ψ ^{. _{= [(Ψ. Case1 + ψ}} . Case2) + r * ψ. ψ calculated as _case3 ] / p + q + r and thus calculated ^. Is applied as the offset correction value of the speed sensor to control when turning.

As described above, according to the present embodiment, the offset correction values are applied to three models, and the offset correction values ψ ^. _comp ^(ψ. _case1) and ^ψ. _comp1 (ψ ^. _case2 ) and ψ ^. _comp2 ^(ψ. _case3) one after the input element for Vx divided into Vxslow, Vxmedium, Vxfast, Vxveryfast and detailed distinction about the input element δswA to δswAsmall, δswAmedium, δswAlarge, δswAverylarge calculated and then the weight ( One output element of p, q or r is mainly applied according to the control state among the output elements p, q and r given the weighting factor).

Subsequently, one of the output elements p, q, r given the weighting factor is mainly applied, and then p, q, r and _case1 , ψ ^. _case2 , ψ ^. Average correction value ψ through _case3 relationship ^. By applying the offset correction value of the speed sensor and performing each model as a mixed fuzzy logic, the natural control flow and the more accurate control without splashing in the boundary region (Case1-> Case2) where the control region is over ESC control can be implemented.

1 is a flowchart and calculation mathematical equation for a method of correcting a turning speed sensor offset of a vehicle according to the present invention.

2 is a vehicle state diagram in which a turning speed sensor offset correction method of a vehicle is implemented according to the present invention.

3, 4, 5 is a control flow chart through the turning speed sensor offset correction of the vehicle according to the present invention

Claims (6)

For Vx, res and DswaA, res, which are the minimum resolution (Vx) and steering wheel angle (δswA) of the reference value at the time of turning the vehicle, the reference values are respectively 0 <Vx <Vx, res A correction mode determination step of determining a satisfactory a state (Case 1) and an exceeding b state (Case 2) according to whether or not the condition of 0 <│δswA | <│δswA, res│ is satisfied; If the state a (Case 1) satisfies 0 < Vx < Vx, res and 0 & lt ^; _mean (measured turning speed value of the vehicle speed sensor)-ψ ^. _{temp, offset} (temporary offset value initialized to 0) = ψ ^. After temporarily calculating _comp (temporary offset correction value), the ψ ^. offset value according to the magnitude value of 0 of _comp ^. _{Find the offsets} sequentially, then ψ ^. _mean -ψ ^. _offset = ψ ^. calculating a _comp (finally corrected revolution speed value) and applying a sequential offset correction algorithm to repeat this process with a constant loop time; The b state (Case 2) does not satisfy the a state (Case 1), but simultaneously satisfies │ δswA, res│ <│δswA │ <│δswA, ss│ with the conditions Vx, res <Vx <Vx, ss Ψ calculated in the a state (Case 1) ^. Calculated current turning vehicle speed ψ, with _comp ^. _{ws, dynamics} = (Vl-Vr) / 2Cf and the measured sensor turning speed value ψ ^. using _mean , ψ ^. _offset [offset correction value] [ψ ^. _{offset = w (s) (ψ} mean -.. ψ ws, dynamics)] to obtain, ^ψ. _comp1 (finally corrected revolution speed value) = ψ ^. _mean -ψ ^. Perform a first model-based offset correction algorithm for recalculating the _offset , and use the steering angle sensor measurement to drive the current turning vehicle speed ψ ^. _{swA, dynamics} [ψ ^. _{swA, dynamics} = (Vx * δRw) / {[V ² x /) g / kund)] + lf + lr}] and the measured sensor turning speed value ψ ^. using _mean , ψ ^. _offset2 (offset correction value) [ψ ^. _offset = w (s) (ψ ^. _mean -ψ ^. _{swA, dynamics} )] ^. _comp2 (finally corrected revolution speed value) = ψ ^. _mean -ψ ^. _After performing a second model-based offset correction algorithm to obtain the _offset again, ψ ^. _comp and ψ ^. _comp1 and ψ ^. _sum all _comp2 and mean value ψ ^. applying an average offset correction algorithm to repeat the process of calculating _{comp, ave} with a constant loop time; The input element Vx is divided into Vxslow, Vxmedium, Vxfast and Vxveryfast for the speed difference, and the input element δswA is divided into δswAsmall, δswAmedium, δswAlarge and δswAverylarge for the steering angle, and then a weighting factor is given. The output element p, q, r is applied to one of the output elements of p, q or r, depending on the control state ^. _comp and ψ ^. _comp1 and ψ ^. _{sum comp2} and take the p, q, and r above into the average correction value ^. Applying an integrated fuzzy logic correction algorithm that obtains and applies the offset correction value of the speed sensor; The turning speed sensor offset correction method of the vehicle, characterized in that carried out as. Vl, Vr are the left and right wheel speeds of the non-drive shaft in a two-wheel drive vehicle, w (s) is ψ ^. Low pass filter in the form of 1 / (τs + 1) to filter the _offset value. The ψ of claim 1, wherein the sequential offset correction algorithm is a temporary offset value ^. After initializing _{temp, offset} value to 0, ψ ^. _{temp, offset} -ψ ^. _mean = ψ ^. After calculating _comp Calculated ψ ^. _{If comp} is greater than 0, n _YOR values are added by 1, but the calculated ψ ^. _{If comp} is equal to or less than 0, the process of subtracting the n _YOR value by 1 is repeated ^. If the value of n _YOR is greater than the value of N _counter, ψ ^. _offset to Δψ ^. _ss is added, or if n _YOR is less than -N _counter value, then ψ ^. _offset to Δψ ^. _After subtracting by the value of _ss , while initializing the value of n _YOR to 0, ψ ^. _After calculating the _offset ψ ^. _mean -ψ ^. _offset = ψ ^. _A method of correcting a turning speed sensor offset of a vehicle, characterized in that performed through a procedure for calculating _{comp (} finally corrected turning speed value). The N _counter and Δψ ^. _ss is a design parameter The ψ of claim 2, wherein the n _YOR value is between −N _counter values and N _counter values ^. _{Since the offset} is 0, the offset speed correction method of the vehicle, characterized in that does not correct the offset (Offset) value. The method of claim 1, wherein, in the applying of the average offset correction algorithm, the steering degree Vx of the vehicle does not exceed Vx, ss and the steering wheel angle │ δswA │ does not exceed │ δswA, ss│. In the case, it is determined that the vehicle belongs to a steady state, and the control of the turning speed sensor offset correction method for the vehicle, characterized in that the control is continuously performed. The method according to claim 1, wherein in the step of applying the average offset correction algorithm, when the vehicle dependency degree Vx exceeds Vx, ss and the steering wheel angle | δswA | is larger than | δswA, ss |, And determining the vehicle is out of a steady state, and performing the control without correcting the offset value. The method of claim 1, wherein ψ ^. To calculate ψ ^. _comp- > ψ ^. _{case 1} , ψ ^. _comp1- > ψ ^. _case2 , ψ ^. _comp2- > ψ ^. _replace with _case3 , Ψ for the output element p given the weighting factor ^{. _{= [(P * ψ. Case1}} ) + (ψ. Case2 + ψ. Case3)] calculated by the / p + q + r, and Ψ for the output element q given the weighting factor ^. = [ψ ^{. _{case1 + (q * ψ. case2}} ) + ψ. calculated as _case3 ] / p + q + r, Ψ for the output element r given the weighting factor ^{. _{= [(Ψ. Case1 + ψ}} . Case2) + r * ψ. _case3 ] / p + q + r, wherein the turning speed sensor offset correction method for a vehicle.

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