KR102659755B1 - A method for estimating tire wear using Effective Rolling Radius - Google Patents

Abstract

A first step of filtering the data collected by the data collection unit and tracking ERR (Effective Rolling Radius) in the calculation unit that performs the calculation according to an embodiment of the present invention; In the calculation unit, a second step of correcting the ERR based on the Contact Ratio; In the calculation unit, a third step is to check whether the ERR increases; In the calculation unit, a fourth step of generating a chart of the wear rate while the ERR increases; A fifth step of outputting wear in the case where ERR increases in the calculation unit; In the calculation unit, when the ERR decreases, a sixth step of correcting the ERR based on the Contact Ratio; In the calculation unit, a seventh step of estimating tire wear using the linear relationship between ERR and tire wear in the area where ERR decreases; And an eighth step of outputting wear in the case where the ERR decreases in the calculation unit.

Description

{A method for estimating tire wear using Effective Rolling Radius}

The present invention relates to a method for estimating tire wear using the effective rolling radius. More specifically, the effective rolling radius (ERR) obtained through the linear speed of the tire and the rotational speed of the tire is referred to as 'ERR'. This is about a method of estimating tire wear using the effective turning radius, which converts to ERR considering the air pressure and load of the tire using the factor and estimates tire wear through the correlation between ERR and tire wear.

In general, tires support the entire load of a car, absorb shock from the road surface through a buffering action, and enable basic driving, stopping, and direction changes of the car through friction between the road surface and the tires.

The part of a tire that comes in contact with the road surface is called the tread. After being installed on a car, the tread wears out due to contact with the ground as driving time passes.

If wear occurs on the tread of a tire, a problem occurs in which the vehicle's steering and braking performance may not operate properly. If the tread wear becomes severe, not only is it exposed to risks such as punctures, but in severe cases, the tire may burst. This phenomenon also occurs.

Accordingly, it is important for safe driving to check the wear of the vehicle's tires and replace the tires at an appropriate time to prevent accidents caused by tire rupture. However, most drivers lack common sense about tires, so the wear and tear of the tires is poor. Many people are unaware of this, and as a result, they are exposed to the risk of accidents by continuing to drive their cars with the tires' wear limit exceeded.

As a result, most tire manufacturers provide a wear indicator within the circumference of the tire or tire groove so that drivers can check when to replace the tire and take appropriate measures according to the wear condition of the tire.

However, in order to check tire wear and lifespan, the driver must visually check the wear indicator mark.

At this time, if the driver does not periodically check the level of tire wear, there is a problem that a major accident may occur due to severely worn tires because the tires are not replaced even though they are severely worn.

In addition, in the case of a method where the driver visually checks the tires, it is difficult to objectively judge the timing of tire replacement, and there are problems in that the degree of tire wear must be individually checked for each wheel of the vehicle, and the existing tire wear indicator By displaying the wear limit, it only indicates when to replace the tire, but does not provide any information on how much the tread of the tire is worn, which makes it impossible to predict when to replace the tire in advance.

In Republic of Korea Patent No. 10-1741730 (title of the invention: vehicle tire monitoring system and control method thereof), a pressure measuring unit that measures the pressure of tires mounted on a vehicle and a mileage measuring unit that measures the driving distance of the tires and a communication unit that receives tire wear data from a tire database and calculates the wear of the tires mounted on the vehicle based on the measured tire pressure, the measured mileage, and the received wear data, and the calculated wear is in advance. A tire monitoring system is disclosed, which includes a control unit that warns the user if the tire is above a set threshold.

(Patent Document 1) Republic of Korea Patent No. 10-1741730 (2017.05.24)

The purpose of the present invention to solve the above problems is to utilize the vehicle mileage wear curve, which is a method of experimentally predicting the amount of tire wear caused by friction with the road surface for each mileage of the tire, in areas where ERR increases. The amount of tire wear is estimated, and in areas where ERR decreases, the ERR and Contact Ratio are obtained and converted to reference values using the linear speed of the tire measured by GPS and the rotational speed of the tire measured by the wheel speed sensor and TMS. , it provides a tire wear estimation method using the effective turning radius to estimate the amount of tire wear using the linear relationship between ERR and tire wear.

The technical problem to be achieved by the present invention is not limited to the technical problem mentioned above, and other technical problems not mentioned can be clearly understood by those skilled in the art from the description below. There will be.

The configuration of the present invention to achieve the above object includes a first step of filtering the data collected by the data collection unit and tracking ERR (Effective Rolling Radius) in the calculation unit that performs the calculation; A second step of correcting ERR based on Contact Ratio in the calculation unit; A third step of checking, in the calculation unit, whether the ERR increases; A fourth step of estimating, in the calculation unit, the wear rate while the ERR increases using a database; A fifth step of outputting wear in the case where the ERR increases in the calculation unit; A sixth step of correcting the ERR based on the Contact Ratio when the ERR decreases in the calculation unit; A seventh step of estimating the wear of the tire by using the linear relationship between the ERR and the wear amount of the tire in the part where the ERR decreases in the calculation unit; and an eighth step of outputting, in the calculation unit, the wear when the ERR decreases.

In an embodiment of the present invention, in the first step, the data collection unit may be composed of one or more sensors selected from Standalone GPS and sensors capable of measuring wheel speed and a TMS (Tire Mounted Sensor).

In an embodiment of the present invention, in the fourth step, in the area where the ERR increases, tire wear can be estimated using a wear curve for each mileage of the vehicle.

In an embodiment of the present invention, in the fourth step, the wear curve for each mileage of the vehicle can predict the amount of wear of the tire caused by friction with the road surface for each mileage of the tire.

In an embodiment of the present invention, in the third step, if the current value of the ERR is greater than the first value of the ERR, it is determined that the ERR increases, and the current value of the ERR is determined to be greater than the first value of the ERR. If the value is smaller than the value, it can be determined that the ERR decreases.

In an embodiment of the present invention, in the second or sixth step, the Contact Ratio can be obtained from the TMS, and the Contact Ratio can be derived by the following equation.

(here, is the biting rate, is the tire pressure, is the value for the load on the tire.)

In an embodiment of the present invention, in the sixth step, the current ERR can be converted to Reference ERR and the current Contact Ratio can be converted to Reference Contact Ratio.

In an embodiment of the present invention, in the sixth step, the Reference ERR and the Reference Contact Ratio can be derived by the following equation.

(here, is the value of Reference ERR, is the value of Reference Contact Ratio, is the current ERR value, is the current Contact Ratio value.)

In an embodiment of the present invention, in the seventh step, the linear relationship between the ERR and the wear amount of the tire can be derived from a database of the ERR linear relationship according to wear occurring in a buffed tire, which is an artificially worn tire. there is.

In an embodiment of the present invention, in the seventh step, the current wear amount of the tire can be estimated by fitting the ERR and substituting the ERR value of the fitted line into the linear relationship.

The configuration of the present invention for achieving the above object includes a calculation unit that calculates the amount of tire wear by performing a tire wear estimation method using the effective turning radius; and a display that receives information about the wear amount of the tire from the calculation unit and displays the wear state of the tire.

The configuration of the present invention for achieving the above object includes a tire wear status display device; and a warning device that receives information on the amount of tire wear from the calculation unit and displays a warning signal when the amount of tire wear exceeds a preset reference value. .

The effect of the present invention according to the above configuration is that, in areas where ERR increases, the tire wear curve by mileage of the vehicle, which is a method of experimentally predicting the amount of tire wear caused by friction with the road surface for each mileage of the tire, is used to predict the tire wear curve. The amount of wear is estimated, and in areas where ERR decreases, the ERR and Contact Ratio are obtained and converted to reference values using the linear speed of the tire measured by GPS and the rotational speed of the tire measured by the wheel speed sensor and TMS. The amount of tire wear can be estimated by using the linear relationship between ERR and tire wear, and by taking into account the uneven increase in ERR in the early stages of tire wear and the amount of change due to tire air pressure and load, etc. As the amount of tire wear is estimated using different methods in areas where ERR increases and areas where ERR decreases, the accuracy of estimating tire wear increases.

The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

Figure 1 is an image showing factors in a tire for defining ERR.
Figure 2 is an image showing that the tread thickness of a tire decreases as tire wear progresses.
Figure 3 is a conceptual diagram showing an algorithm for a tire wear estimation method using the effective turning radius according to an embodiment of the present invention.
Figure 4 is a flowchart showing a method for estimating tire wear using the effective turning radius according to an embodiment of the present invention.
Figure 5 is a graph showing the results of an actual vehicle test performed by performing a tire wear estimation method using the effective turning radius according to an embodiment of the present invention.
Figure 6 is a graph showing the results of an actual vehicle test by tracking the ERR from the ERR value where the ERR began to decrease by performing a tire wear estimation method using the effective turning radius according to an embodiment of the present invention.
Figure 7 is a graph showing the results of estimating the amount of tire wear while the vehicle travels 45,000 km by performing an actual vehicle test by performing a tire wear estimation method using the effective turning radius according to an embodiment of the present invention.

Hereinafter, the present invention will be described with reference to the attached drawings. However, the present invention may be implemented in various different forms and, therefore, is not limited to the embodiments described herein. In order to clearly explain the present invention in the drawings, parts unrelated to the description are omitted, and similar parts are given similar reference numerals throughout the specification.

Throughout the specification, when a part is said to be "connected (connected, contacted, combined)" with another part, this means not only "directly connected" but also "indirectly connected" with another member in between. "Includes cases where it is. Additionally, when a part is said to “include” a certain component, this does not mean that other components are excluded, but that other components can be added, unless specifically stated to the contrary.

The terms used in this specification are merely used to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.

Figure 1 is an image showing factors in a tire for defining ERR.

When explaining ERR (Effective Rolling Radius) with reference to FIG. 1, first, ERR is called effective turning radius, effective rolling radius, or effective wheel radius, and is related to the relationship between the constant linear speed and rotation speed of the tire 10. As a parameter, when the vehicle is driven, the entire diameter of the tire 10 does not work, but the part of the tire 10 that touches the ground is buried in the soil, the distance from the vehicle side to the point where actual driving occurs. It also means the radius calculated by calculating the length of one rotation of the tire 10 as the circumferential length.

Additionally, when explaining the factors shown in Figure 1, represents the distance from the center of the tire 10 to the end of the tread in a situation where no load is applied to the tire 10, represents the minimum value of the distance from the center of the tire 10 to the end of the tread in a situation where a vertical load is applied to the tire 10, represents the linear velocity of the tire 10 divided by the angular velocity of the tire in a situation where a vertical load is applied to the tire 10.

here, The value of or ERR is a value that exists between any two factors selected from the above three factors, and is a factor that can be obtained from Standalone GPS, wheel speed sensor, and TMS (Tire Mounted Sensor). .

above Can be calculated by [Equation 1] below.

[Formula 1]

(here, is the linear speed of the tire, is the angular velocity of the tire.)

The above-mentioned ERR is a factor that is highly correlated with the wear of the tire 10, and is a factor that can be easily obtained from the linear speed and rotational speed of the tire 10. Therefore, conventional rotational speed data was used to determine the tire 10 through ERR. Wear estimation techniques have been reported.

However, as the wear of the tire 10 progresses, the ERR increases unevenly at the beginning and then decreases, and there is a problem in that the ERR changes even under the same wear condition depending on the air pressure and load of the tire 10.

Accordingly, the tire wear estimation method using ERR of the present invention uses the linear speed of the tire 10 obtained from GPS and the rotational speed of the tire 10 obtained from the wheel speed sensor and TMS (Tire Mounted Sensor). The obtained ERR is converted into an ERR considering the air pressure and load of the tire (10) obtained using the contact ratio obtained through TMS, and here, the wear of the tire (10) is calculated through the correlation between the wear of the tire (10) and the tracked ERR. It is possible to estimate the amount of wear, and this will be explained later.

Figure 2 is an image showing that the tread thickness of a tire decreases as tire wear progresses.

Referring to FIG. 2, it can be intuitively seen that the distance from the ground to the center of the tire 10 decreases as the wear of the tire 10 progresses.

In addition, it can be seen that the ERR decreases as the tread thickness of the tire 10 decreases as the wear of the tire 10 progresses.

Figure 3 is a conceptual diagram showing an algorithm for a tire wear estimation method using the effective turning radius according to an embodiment of the present invention.

Referring to FIG. 3, the ERR initially increases and then decreases as the wear of the tire 10 progresses. The portion that increases initially increases unevenly, resulting in a correlation between the ERR and the amount of wear of the tire 10. I can't get a relationship.

Accordingly, in areas where the initial uneven increase occurs, an alternative algorithm is needed rather than using an algorithm that utilizes the ERR value. Since ERR is correlated with the air pressure and load of the tire 10, the air pressure and load of the tire 10 are needed. A conversion is also needed.

Here, in the method of estimating tire wear using the effective turning radius of the present invention, it is divided into a part where ERR increases and a part where ERR decreases, and different methods are used to estimate the wear of the tire 10 in each part. do.

In areas where the above-mentioned ERR increases, wear is estimated using the vehicle's wear-mileage curve, which is an existing database, and in areas where ERR decreases, wear is estimated using the linear relationship between ERR and the wear amount of the tire 10. Estimate wear and tear.

Here, the mileage represents the driving distance of the vehicle, and the wear-mileage curve for each mileage is formed using data obtained by experimentally measuring the amount of wear of the tire 10 according to the driving distance of the tire 10. It could be a graph.

Hereinafter, the method for estimating tire wear using the effective turning radius of the present invention will be described in more detail.

Figure 4 is a flowchart showing a method for estimating tire wear using the effective turning radius according to an embodiment of the present invention.

Additionally, Figure 4 shows an enlarged version of part A of Figure 3.

Referring to FIG. 4, first, in step S110, the calculation unit that performs the calculation filters the data collected by the data collection unit and tracks the ERR (Effective Rolling Radius).

Here, the data collection unit may be composed of one or more sensors selected from standalone GPS and sensors capable of measuring wheel speed, and a TMS (Tire Mounted Sensor).

The sensor capable of measuring the wheel speed described above may be composed of various sensors capable of measuring wheel speed, such as a wheel speed sensor and TMS.

In the present invention, it is explained that the data collection unit is composed of one or more sensors selected from Standalone GPS and sensors capable of measuring wheel speed and a TMS (Tire Mounted Sensor), but the present invention is not limited to this, and the linear speed of the tire 10 or It may be composed of various sensors capable of measuring the rotational speed of the tire 10.

Next, in step S120, the calculation unit corrects the ERR based on the Contact Ratio.

At this time, the Contact Ratio can be obtained from TMS, and the Contact Ratio can be derived using [Equation 2] below.

[Formula 2]

(here, is the biting rate, is the tire pressure, is the value for the load on the tire.)

The above [Equation 2] used MatLab to create a contact ratio map according to air pressure and load.

Specifically, a fitting polynomial of contact ratio according to x: air pressure and y: load for polynomial curved surface fitting was formed from [Equation 2-a] as shown below.

[Formula 2-a]

In [Equation 2], the engagement rate may be the ratio of the contact area between the tread and the ground to the total area of the tread of the tire 10.

In addition, the f (Inflation Pressure, Load) function experimentally measures the air pressure of the tire 10 and the engagement rate according to the load on the tire 10, collects data on this, and calculates the data from the graph created using the data. It may be a derived function. This is a known technique for deriving a function using measurement data, and detailed description will be omitted. The following is the same.

Next, in step S130, the calculation unit checks whether the ERR increases using the ERR corrected in step S120.

At this time, if the current value of ERR is greater than the initial value of ERR, it is determined that ERR is increasing, and if the current value of ERR is smaller than the initial value of ERR, it is determined that ERR is decreasing.

And, in order to determine whether the ERR increases or decreases, the ERR is first corrected by the contact ratio as a reference standard, and then the increase or decrease of the ERR is determined.

Here, if the current value of ERR is confirmed to be greater than the initial value of ERR and it is determined that ERR is increasing, the process proceeds to step S140.

In step S140, the calculation unit estimates the wear rate while the ERR increases using a database.

Here, in the area where ERR increases, wear of the tire 10 is estimated using a wear curve for each mileage of the vehicle.

Specifically, the wear curve according to the mileage of the vehicle predicts the amount of wear of the tire 10 caused by friction with the road surface according to the driving mileage of the tire 10.

More specifically, the amount of wear of the tire 10 can be predicted by substituting the mileage of the tire 10 into the wear curve for each mileage of the vehicle and using the obtained amount of wear.

Next, in step S150, the calculation unit outputs wear when ERR increases.

Afterwards, return to step S110 and repeat steps S150 to determine whether the ERR increases or decreases, and repeatedly perform steps S110 to S150 until the ERR begins to decrease.

Meanwhile, in the above-described step S130, if the current value of ERR is confirmed to be smaller than the initial value of ERR and it is determined that ERR is decreasing, the process proceeds to step S210.

In step S210, when the ERR decreases in the calculation unit, the ERR is corrected based on the Contact Ratio. Here, [Equation 2] can be used.

Also, here, the current ERR is converted to Reference ERR, and the current Contact Ratio is converted to Reference Contact Ratio.

At this time, Reference ERR and Reference Contact Ratio are derived by [Equation 3] below.

[Formula 3]

(here, is the value of Reference ERR, is the value of Reference Contact Ratio, is the current ERR value, is the current Contact Ratio value.)

[Formula 3] is a formula derived by an empirical test. Through [Formula 3] described above, the relationship between ERR and Contact Ratio can be known, and Reference ERR and Reference Contact Ratio can be derived.

Figure 5 is a graph showing the results of an actual vehicle test performed by performing a tire wear estimation method using the effective turning radius according to an embodiment of the present invention.

Specifically, Figure 5 is a graph showing ERR data from the average of data obtained from 100 tires (10) while running an actual vehicle test, where LF (Left Front) is ERR data from the left front wheel and RF (Right Front) means ERR data from the right front wheel, LR (Left Rear) means ERR data from the left rear wheel, and RR (Right Rear) means ERR data from the right rear wheel.

Additionally, the graph in FIG. 5 shows the corrected ERR value and the uncorrected ERR value.

In addition, referring to FIG. 5, it can be seen that the ERR data collected while the vehicle is driving on the road is converted into reference ERR, and the dispersion of the ERR value is reduced.

Referring again to FIG. 4, in step S220, the calculation unit estimates the wear of the tire 10 using the linear relationship between the ERR and the wear amount of the tire 10 in the area where the ERR decreases.

[Formula 4]

Wear = f(ERR)

(Here, ERR is the current ERR value, and Wear is the estimated wear amount.)

The above [Equation 4] was fitted to a polynomial curve through MatLab, and was fitted with the following [Equation 4-a], which is a first-order polynomial relationship.

[Formula 4-a]

f = ax + b

Additionally, in [Equation 4], the f(ERR) function is a function for a linear relationship obtained by converting ERR data experimentally collected during road driving of a vehicle into Reference ERR, as shown in FIGS. 5 and 6.

Specifically, from the time the current value of ERR begins to become smaller than the initial value of ERR, the wear of the tire 10 is determined through the linear relationship between ERR, which is an algorithm used in the part where the ERR is reduced, and the wear amount of the tire 10. can be estimated.

Here, the linear relationship between ERR and the wear amount of the tire 10 is derived from a database of the ERR linear relationship according to wear occurring in the buffing tire 10, which is an artificially worn tire 10, and is f(ERR) as described above. ) can form a function.

The buffed tire 10 refers to a tire 10 that has been artificially worn. The tire 10 is made by artificially buffing or cutting the outside of the tire 10 using a buffing machine or grinder. This refers to a tire (10) from which the tread and outer materials of the tire (10) have been removed.

Accordingly, since it takes a lot of time and money to naturally abrade the tire 10 each time, a linear relationship is constructed using a buffing tire.

In addition, in the linear relationship between ERR and the wear amount of the tire 10, the naturally worn tire 10 initially increases and then decreases, while the buffed tire 10 shows a decrease from the beginning.

In addition, in the linear relationship between ERR and the wear amount of the tire 10, the slope of the buffed tire 10 is very similar to the slope of the naturally worn tire 10, and accordingly, the buffed tire 10 and the naturally worn tire ( Since there is no difference in the linear relationship in 10), a buffed tire (10) can be used instead of a naturally worn tire (10).

Figure 6 is a graph showing the results of an actual vehicle test by tracking the ERR from the ERR value where the ERR began to decrease by performing a tire wear estimation method using the effective turning radius according to an embodiment of the present invention.

Specifically, Figure 6 is a graph showing ERR data from the average of data obtained from 100 tires (10) while running a real vehicle test, where LF (Left Front) is ERR data from the left front wheel and RF (Right Front) means ERR data from the right front wheel, LR (Left Rear) means ERR data from the left rear wheel, and RR (Right Rear) means ERR data from the right rear wheel.

Additionally, the graph in FIG. 6 shows the corrected ERR value and the uncorrected ERR value, and shows the fitted ERR.

Specifically, referring to FIG. 6, the current wear amount of the tire 10 is estimated by fitting the ERR and substituting the ERR value of the fitted line into a linear relationship.

More specifically, the ERR is tracked from the ERR value where the ERR begins to decrease and fitted as shown in the blue dotted line in FIG. 6, and the ERR value of the fitted dotted line is calculated as the ERR of the buffing tire 10 and the wear amount of the tire 10 described above. The current wear amount of the tire 10 can be estimated by substituting into the linear relationship of .

Next, in step S230, the calculation unit outputs wear when ERR decreases.

Figure 7 is a graph showing the results of estimating the amount of tire wear while the vehicle travels 45,000 km by performing an actual vehicle test by performing a tire wear estimation method using the effective turning radius according to an embodiment of the present invention.

Specifically, Figure 7 is a graph showing the amount of wear that occurs depending on the position of the tire 10 in a running vehicle while performing an actual vehicle test, where a at FL (Front Left) is the actual amount of wear on the left front wheel, and FL ( In Front Left), b is the estimated wear amount on the left front wheel, in FR (Front Right), a is the actual wear amount on the right front wheel, and in FR (Front Right), b is the estimated wear amount on the right front wheel, RL (Rear Left) ) in a is the actual wear amount on the left rear wheel, in RL (Rear Left), b is the estimated wear amount in the left rear wheel, in RR (Rear Right) a is the actual wear amount in the right rear wheel, in RR (Rear Right) b refers to the estimated wear amount on the right rear wheel.

As an example, referring to FIG. 7, as a result of measuring and estimating the wear amount of the tire 10 while the vehicle travels 45,000 km through an actual vehicle test, the actual wear amount at FL is 5.07 mm, and the estimated wear amount is 4.83 mm. The error is 0.24mm.

And, the actual wear amount in FR is 5.42mm, and the estimated wear amount is 4.81mm, with an error of 0.61mm.

Additionally, the actual wear amount in RL is 2.06mm, and the estimated wear amount is 2.77mm, with an error of 0.71mm.

In addition, the actual wear amount in RR is 2.57mm, and the estimated wear amount is 2.03mm, with an error of 0.54mm.

Accordingly, when the wear amount of the tire 10 is estimated while the vehicle travels 45,000 km using the tire wear estimation method using the effective turning radius of the present invention, there is an error in the wear amount of the front and rear wheels on both sides. It is possible to obtain results that estimate to within 1mm.

Meanwhile, by performing the tire wear estimation method using the effective turning radius of the present invention, information on the wear amount of the tire 10 is received from the arithmetic unit that calculates the wear amount of the tire 10, and the wear amount of the tire 10 is received. It may include a tire wear status display device including a display that displays the status.

In addition, it includes a warning device that receives information about the wear amount of the tire 10 from the tire wear status display device and calculation unit, and displays a warning signal when the wear amount of the tire 10 exceeds a preset reference value. It may include a tire wear condition management system.

Here, each of the above-described steps S110 to S150 and steps S210 to S230 may be performed by a calculation unit included in the tire wear state display device.

As seen above, the tire wear estimation method using the effective turning radius of the present invention measures the linear speed of the tire 10 and the wheel speed sensor and TMS, which are sensors that can measure the rotational speed of the tire 10. The amount of wear of the tire 10 can be estimated by tracking the trend line of ERR, which is a wear factor of the tire 10, using GPS.

At this time, ERR changes depending on the air pressure and load conditions of the tire 10, but ERR can be tracked through a formula that converts ERR into Reference ERR based on the reference.

Here, as wear of the tire 10 progresses, ERR initially increases and then decreases.

Accordingly, in the tire wear estimation method using the effective turning radius of the present invention, wear of the tire 10 is estimated by using a wear curve for each vehicle mileage in the portion where the ERR initially increases, and the wear of the tire 10 is estimated in the portion where the ERR decreases. In , wear is estimated using the linear relationship between ERR and the wear amount of the tire 10.

In this way, the tire wear estimation method using the effective turning radius of the present invention, which divides the wear of the tire 10 into a part where the ERR increases and a part where the ERR decreases, and estimates the wear of the tire 10 using different methods in each part, uses the tire 10 As the wear of the tire 10 progresses, the accuracy of estimating the wear of the tire 10 may increase.

The description of the present invention described above is for illustrative purposes, and those skilled in the art will understand that the present invention can be easily modified into other specific forms without changing the technical idea or essential features of the present invention. will be. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive. For example, each component described as single may be implemented in a distributed manner, and similarly, components described as distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the patent claims described below, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention.

10: tires

Claims (12)

A first step of filtering the data collected by the data collection unit and tracking ERR (Effective Rolling Radius) in the calculation unit that performs the calculation;
A second step of correcting ERR based on Contact Ratio in the calculation unit;
A third step of checking, in the calculation unit, whether the ERR increases;
A fourth step of estimating, in the calculation unit, the wear rate while the ERR increases using a database;
A fifth step of outputting wear in the case where the ERR increases in the calculation unit;
A sixth step of correcting the ERR based on the Contact Ratio when the ERR decreases in the calculation unit;
A seventh step of estimating the wear of the tire by using the linear relationship between the ERR and the wear amount of the tire in the part where the ERR decreases in the calculation unit; and
An eighth step of outputting, in the calculation unit, the wear when the ERR decreases. A tire wear estimation method using an effective turning radius, comprising:
According to claim 1,
In the first step, the data collection unit is comprised of one or more sensors selected from Standalone GPS and sensors capable of measuring wheel speed and a Tire Mounted Sensor (TMS). Estimation method.
According to claim 1,
In the fourth step, a method for estimating tire wear using an effective turning radius, wherein in the area where the ERR increases, tire wear is estimated using a wear curve for each mileage of the vehicle.
According to claim 3,
In the fourth step, the wear curve for each mileage of the vehicle predicts the amount of wear of the tire caused by friction with the road surface for each mileage of the tire.
According to claim 1,
In the third step, if the current value of the ERR is greater than the initial value of the ERR, the ERR is determined to increase, and if the current value of the ERR is smaller than the initial value of the ERR, the ERR is determined to increase. A method of estimating tire wear using the effective turning radius, which is characterized as decreasing.
According to claim 2,
In the second or sixth step, the contact ratio can be obtained from the TMS, and the contact ratio is derived using the following equation. A method for estimating tire wear using an effective turning radius.

(here, is the biting rate, is the tire pressure, is the value for the load on the tire.)
According to claim 6,
In the sixth step, a tire wear estimation method using the effective turning radius, characterized in that the current ERR is converted to the Reference ERR and the current Contact Ratio is converted to the Reference Contact Ratio.
According to claim 7,
In the sixth step, the Reference ERR and the Reference Contact Ratio are derived by the following equation. A tire wear estimation method using the effective turning radius.

(here, is the value of Reference ERR, is the value of Reference Contact Ratio, is the current ERR value, is the current Contact Ratio value.)
According to claim 1,
In the seventh step, the linear relationship between the ERR and the wear amount of the tire utilizes the effective turning radius, which is derived from a database of the ERR linear relationship according to wear occurring in buffed tires, which are artificially worn tires. How to estimate the wear of one tire.
According to clause 9,
In the seventh step, the current wear amount of the tire is estimated by fitting the ERR and substituting the ERR value of the fitted line into the linear relationship.
a calculation unit that calculates the amount of tire wear by performing a tire wear estimation method using the effective turning radius according to any one of claims 1 to 10; and
A display device that receives information about the wear amount of the tire from the calculation unit and displays the wear state of the tire.
Tire wear status display device according to claim 11; and
A warning device that receives information on the amount of tire wear from the calculation unit and displays a warning signal when the amount of tire wear exceeds a preset reference value.