阅读说明：本技术 一种轮胎自定位系统及其定位方法 (Tire self-positioning system and positioning method thereof ) 是由 王旭 史卫华 任之伟 于 2021-08-16 设计创作，主要内容包括：本发明涉及一种轮胎自定位系统及其定位方法。该轮胎自定位方法包括步骤：S1,数据采集；S2,数据转换；S3,数据补偿；S4,数据统计；S5,根据统计结果判定第一信号对应的轮胎的具体位置。本发明提出了一种轮胎自定位系统及其定位方法,用于解决轮胎发生反向运动问题,提升主动学习的成功率。(The invention relates to a tire self-positioning system and a positioning method thereof. The self-positioning method of the tire comprises the following steps: s1, data acquisition; s2, data conversion; s3, compensating data; s4, data statistics; and S5, judging the concrete position of the tire corresponding to the first signal according to the statistical result. The invention provides a tire self-positioning system and a positioning method thereof, which are used for solving the problem of reverse movement of a tire and improving the success rate of active learning.)

1. A method of self-positioning a tire, comprising the steps of:

s1, acquiring data, namely acquiring a wireless signal and a wired signal of the tire, wherein the wireless signal can index the corresponding time when a first signal reaches a reference point, the first signal at least comprises acceleration information of the tire, the wired signal comprises a second signal and corresponding position information of the tire, and the second signal at least comprises rotation angle information of the tire;

s2, converting data, and calculating the reference rotation angle information of the corresponding tire when the first signal reaches a reference point according to the currently received wireless signal and wired signal;

s3, data compensation, if the tire rotates reversely, the reference rotation angle information obtained after the tire rotates reversely is compensated;

s4, carrying out data statistics, repeatedly executing the steps S1 to S3, and carrying out deviation degree statistics on the obtained queue of the reference rotation angle information;

and S5, judging the specific position of the tire corresponding to the first signal according to the statistical result.

2. The tire self-positioning method of claim 1 wherein said tire rotation angle information comprises the ABS tooth number of said tire rotation, said wire signal is obtained in step S1, said ABS tooth number is saved, and a code value is generated, a plurality of said code values form a code value queue;

in step S2, calculating reference rotation angle information of the tire corresponding to the first signal reaching a reference point according to the currently received wireless signal and wired signal, and recording the reference rotation angle information as a reference encoded value;

in step S3, if there is a reverse rotation of the tire, the reference code value acquired after the reverse rotation of the tire is compensated.

3. The method for self-positioning a tire according to claim 2, wherein the step of compensating said reference code value in step S3 comprises:

s31, recording the number of ABS teeth at the beginning of the reverse motion as AbsStart, and recording the number of ABS teeth at the end of the reverse motion as AbsEnd;

s32, calculating an offset ABS, which is [2 × (AbsEnd + n × ABS _ CODE _ MAXVAL-AbsStart) ]% ABS _ CODE _ MAXVAL remainder;

n is a natural number, n is adjusted to make AbsEnd + n × ABS _ CODE _ MAXVAL greater than AbsStart, ABS _ CODE _ MAXVAL being the number of teeth the ABS increases for one revolution of the tire;

s33, compensating the reference code value acquired after the tire rotates in the reverse direction, and if the current reference code value ABS _ ref is greater than or equal to the compensation value ABS, compensating the reference code value ABS as the reference code value ABS _ ref — the compensation value ABS; if the current reference CODE value ABS _ ref < the compensation value ABS, the compensation reference CODE value ABS is equal to the reference CODE value ABS _ ref + ABS _ CODE _ MAXVAL — the compensation value ABS.

4. The self-positioning method for tires according to claim 3, wherein step S31 comprises:

s311, recording the total tooth number of the ABS when the reverse motion starts, and recording the total tooth number of the ABS when the reverse motion ends, and recording the total tooth number as AbsTotalEnd;

s312, calculating the ABS tooth count at the beginning of the reverse motion, and calculating the ABS tooth count at the end of the reverse motion, where AbsStart ═ AbsTotalStart% ABS _ CODE _ MAXVAL is left, and AbsEnd ═ abstotaltend% ABS _ CODE _ MAXVAL is left.

5. The method for self-positioning a tire according to claim 2, wherein the step of compensating said reference code value in step S3 comprises:

s31', recording the total number of teeth of ABS at the beginning of reverse motion, and recording the total number of teeth of ABS at the end of reverse motion, and recording the total number of teeth of ABS as AbsTotalEnd;

s32', calculating the accumulated increased ABS tooth number abstotaltdeltat-abstotaltstart during the reverse motion;

s33', compensating the reference CODE value acquired after the tire is reversely rotated, the compensation reference CODE value ABS [ reference CODE value ABS _ ref + (ABS _ CODE _ MAXVAL × n) - (2 × abstotalteltadel) ]% ABS _ CODE _ MAXVAL being left;

wherein ABS _ CODE _ MAXVAL is the number of teeth ABS increases for one revolution of the tire, n is a natural number, and n is adjusted such that the reference CODE value ABS _ ref + (ABS _ CODE _ MAXVAL × n) is greater than 2 × abstotaltelta.

6. The method for self-positioning a tire according to claim 2, wherein in step S3, if there are n times of reverse rotation of said tire, the reference code value obtained after the n times of reverse rotation is compensated, comprising the steps of:

recording the total number of ABS teeth at the beginning of the first reverse motion, which is denoted as AbsTotalStart 1, recording the total number of ABS teeth at the end of the first reverse motion, which is denoted as AbsTotalEnd 1, and calculating the number of ABS teeth increased during the first reverse motion, which is AbsTotalDelta 1-AbsTotalStart 1;

according to the steps, recording the number of the ABS teeth increased from the second reverse movement to the nth reverse movement, accumulating the number of the ABS teeth increased from the first reverse movement to the nth reverse movement, and accumulating the increased number of the ABS teeth AbsTotalDelta which is AbsTotalDelta 1+ AbsTotalDelta 2+ … … + AbsTotalDelta n;

correcting the ABS total tooth number AbsTotalAdjusted (reference CODE value ABS _ ref + (ABS _ CODE _ MAXVAL × n) -2 abstotaltelta)% ABS _ CODE _ MAXVAL, n being a natural number, adjusting the value of n so that the reference CODE value ABS _ ref + (ABS _ CODE _ MAXVAL _ n) is greater than 2 abstotaltal delta;

the compensation reference CODE value ABS is obtained by the remainder of the correction ABS total tooth number AbsTotalAdjusted% ABS _ CODE _ MAXVAL;

the reference encoding value ABS _ ref is compensated by compensating the reference encoding value ABS.

7. The self-positioning method for tires according to claim 2, wherein step S2 comprises:

s21, recording the time interval T1 of the currently received wireless signal and wired signal;

s22, obtaining a backtracking time T2 from the first signal reaching a reference point to the wireless signal receiving;

s23, indexing time T3 ═ backtracking time T2-time interval T1;

s24, calculating the number of code values needed to index back, wherein the number is the index time T3/the cycle ABS _ period of the second signal;

s25, according to the number of the backward index, recording the indexed encoding value ABS _ search in the encoding value queue;

and S26, correcting the code value ABS _ search, and acquiring the reference code value ABS _ ref.

8. The tire self-positioning method according to claim 7, wherein said backtracking time T2 is a fixed value set or a specific value calculated by a specific algorithm.

9. A self-positioning system for tyres, carrying out the method for self-positioning tyres of claim 1, characterized in that it comprises:

a tire;

the tire condition detection device is arranged on the tire and used for acquiring the first signal, the pressure, the temperature and the identification code of the tire and generating the wireless signal;

the second signal sensor is arranged on the tire and used for acquiring the second signal;

the second signal controller is electrically connected with the second signal sensor, receives the second signal and generates a wired signal, and the wired signal comprises a code value corresponding to the second signal and position information of a tire where the second signal sensor is located;

a communication bus and a signal receiving processor, the signal receiving processor receiving the wired signal through the communication bus, the signal receiving processor receiving the wireless signal, the signal receiving processor performing the steps of data conversion, data compensation and data statistics according to the wireless signal and the wired signal.

10. The tire self-positioning system of claim 9 wherein said first signal acquisition sensor is an acceleration sensor and said second signal sensor is an ABS tooth pulse sensor.

Technical Field

The invention relates to the technical field of vehicle tire positioning, in particular to a tire self-positioning system and a positioning method thereof.

Background

A tire condition monitoring system is a safety system for ensuring good running of a vehicle, and as a regulatory requirement item, a tire condition monitoring system has been rapidly developed in the automobile market in recent years. The running state of the automobile tire can be monitored in real time, and when the tire is in an abnormal state such as air leakage or ultrahigh temperature, a warning can be given to a driver in time, so that the tire can be prevented from being damaged to the maximum extent, and a good guarantee is provided for the safe running of the automobile. As an active safety system of an automobile, the tire condition monitoring system can prevent the tire burst of the automobile and avoid accidents. In addition, inflating the tire to the recommended standard pressure value also reduces fuel consumption of the vehicle, allowing the tire to be used for a longer period of time.

In order to accurately monitor the condition of each tire, specific positions [ front left FL, front right FR, rear right RR, rear left RL ] of a tire can be accurately displayed when the pressure or temperature of the tire is abnormal. After the tire condition monitoring system is installed, the installation position of the tire air pressure detecting device is determined, and this process of identifying the position of the tire condition detecting device is generally referred to as "tire condition monitoring system tire position learning". Tire position learning of a tire condition monitoring system is divided into passive learning and active learning, wherein the tire position learning realized by a special diagnostic instrument and other tools is called passive learning, and the tire position learning which is completed by the tire condition monitoring system without an additional auxiliary device by utilizing a device which is already present on a whole vehicle is called tire condition monitoring system active learning. Compared with passive learning, a professional person needs to learn the ID through a special diagnosis tool, active learning can save installation time, and autonomous learning of the tire position can be completed without professional after-sales personnel and special diagnosis instruments

If the vehicle moves in the reverse direction during the autonomous learning of the tire position, the tire condition detecting device may fail to be positioned.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a tire self-positioning system and a positioning method thereof, which are used for solving the problem of reverse movement of a tire and improving the success rate of active learning.

Specifically, the invention provides a tire self-positioning method, which comprises the following steps:

s1, acquiring data, namely acquiring a wireless signal and a wired signal of the tire, wherein the wireless signal can index the corresponding time when a first signal reaches a reference point, the first signal at least comprises acceleration information of the tire, the wired signal comprises a second signal and corresponding position information of the tire, and the second signal at least comprises rotation angle information of the tire;

s2, converting data, and calculating the reference rotation angle information of the corresponding tire when the first signal reaches a reference point according to the currently received wireless signal and wired signal;

s3, data compensation, if the tire rotates reversely, the reference rotation angle information obtained after the tire rotates reversely is compensated;

s4, carrying out data statistics, repeatedly executing the steps S1 to S3, and carrying out deviation degree statistics on the obtained queue of the reference rotation angle information;

and S5, judging the specific position of the tire corresponding to the first signal according to the statistical result.

According to an embodiment of the present invention, the tire rotation angle information includes ABS tooth number of the tire rotation, the wired signal is obtained in step S1, the ABS tooth number is saved, and a code value is generated, and a plurality of the code values form a code value queue;

in step S2, calculating reference rotation angle information of the tire corresponding to the first signal reaching a reference point according to the currently received wireless signal and wired signal, and recording the reference rotation angle information as a reference encoded value;

in step S3, if there is a reverse rotation of the tire, the reference code value acquired after the reverse rotation of the tire is compensated.

According to one embodiment of the present invention, in step S3, if there are a plurality of counter rotations of the tire, the reference code value acquired after each counter rotation is compensated after the counter rotation.

According to an embodiment of the present invention, the step of compensating the reference encoded value in step S3 includes:

s31, recording the number of ABS teeth at the beginning of the reverse motion as AbsStart, and recording the number of ABS teeth at the end of the reverse motion as AbsEnd;

s32, calculating an offset ABS, which is [2 × (AbsEnd + n × ABS _ CODE _ MAXVAL-AbsStart) ]% ABS _ CODE _ MAXVAL remainder;

n is a natural number, n is adjusted to make AbsEnd + n × ABS _ CODE _ MAXVAL greater than AbsStart, ABS _ CODE _ MAXVAL being the number of teeth the ABS increases for one revolution of the tire;

s33, compensating the reference code value acquired after the tire rotates in the reverse direction, and if the current reference code value ABS _ ref is greater than or equal to the compensation value ABS, compensating the reference code value ABS as the reference code value ABS _ ref — the compensation value ABS; if the current reference CODE value ABS _ ref < the compensation value ABS, the compensation reference CODE value ABS is equal to the reference CODE value ABS _ ref + ABS _ CODE _ MAXVAL — the compensation value ABS.

According to an embodiment of the present invention, step S31 includes:

s311, recording the total tooth number of the ABS when the reverse motion starts, and recording the total tooth number of the ABS when the reverse motion ends, and recording the total tooth number as AbsTotalEnd;

s312, calculating the ABS tooth count at the beginning of the reverse motion, and calculating the ABS tooth count at the end of the reverse motion, where AbsStart ═ AbsTotalStart% ABS _ CODE _ MAXVAL is left, and AbsEnd ═ abstotaltend% ABS _ CODE _ MAXVAL is left.

According to an embodiment of the present invention, the step of compensating the reference encoded value in step S3 includes:

s31', recording the total number of teeth of ABS at the beginning of reverse motion, and recording the total number of teeth of ABS at the end of reverse motion, and recording the total number of teeth of ABS as AbsTotalEnd;

s32', calculating the accumulated increased ABS tooth number abstotaltdeltat-abstotaltstart during the reverse motion;

s33', compensating the reference CODE value acquired after the tire is rotated in the reverse direction, the compensation reference CODE value ABS [ reference CODE value ABS _ ref + (ABS _ CODE _ MAXVAL) × n) - (2 × abstotalteltaDelta) ]/ABS _ CODE _ MAXVAL being left;

wherein ABS _ CODE _ MAXVAL is the number of teeth ABS increases for one revolution of the tire, n is a natural number, and n is adjusted such that the reference CODE value ABS _ ref + (ABS _ CODE _ MAXVAL × n) is greater than 2 × abstotaltelta.

According to an embodiment of the present invention, in step S3, if there are n times of reverse rotations of the tire, the step S3 of compensating the reference code value obtained after the n times of reverse rotations includes the steps of:

recording the total number of ABS teeth at the beginning of the first reverse motion, which is denoted as AbsTotalStart 1, recording the total number of ABS teeth at the end of the first reverse motion, which is denoted as AbsTotalEnd 1, and calculating the number of ABS teeth increased during the first reverse motion, which is AbsTotalDelta 1-AbsTotalStart 1;

according to the steps, recording the number of the ABS teeth increased from the second reverse movement to the nth reverse movement, accumulating the number of the ABS teeth increased from the first reverse movement to the nth reverse movement, and accumulating the increased number of the ABS teeth AbsTotalDelta which is AbsTotalDelta 1+ AbsTotalDelta 2+ … … + AbsTotalDelta n;

correcting the ABS total tooth number AbsTotalAdjusted (reference CODE value ABS _ ref + (ABS _ CODE _ MAXVAL × n) -2 abstotaltelta)% ABS _ CODE _ MAXVAL, n being a natural number, adjusting the value of n so that the reference CODE value ABS _ ref + (ABS _ CODE _ MAXVAL _ n) is greater than 2 abstotaltal delta;

the compensation reference CODE value ABS is obtained by the remainder of the correction ABS total tooth number AbsTotalAdjusted% ABS _ CODE _ MAXVAL;

the reference encoding value ABS _ ref is compensated by compensating the reference encoding value ABS.

According to an embodiment of the present invention, step S2 includes:

s21, recording the time interval T1 of the currently received wireless signal and wired signal;

s22, obtaining a backtracking time T2 from the first signal reaching a reference point to the wireless signal receiving;

s23, indexing time T3 ═ backtracking time T2-time interval T1;

s24, calculating the number of code values needed to index back, wherein the number is the index time T3/the cycle ABS _ period of the second signal;

s25, according to the number of the backward index, recording the indexed encoding value ABS _ search in the encoding value queue;

and S26, correcting the code value ABS _ search, and acquiring the reference code value ABS _ ref.

According to an embodiment of the present invention, the backtracking time T2 is a fixed value or a specific value calculated by a specific algorithm.

The invention also provides a self-positioning system for tyres for carrying out the aforesaid method for self-positioning tyres, comprising:

a tire;

the tire condition detection device is arranged on the tire and used for acquiring the first signal, the pressure, the temperature and the identification code of the tire and generating the wireless signal;

the second signal sensor is arranged on the tire and used for acquiring the second signal;

the second signal controller is electrically connected with the second signal sensor, receives the second signal and generates a wired signal, and the wired signal comprises a code value corresponding to the second signal and position information of a tire where the second signal sensor is located;

a communication bus and a signal receiving processor, the signal receiving processor receiving the wired signal through the communication bus, the signal receiving processor receiving the wireless signal, the signal receiving processor performing the steps of data conversion, data compensation and data statistics according to the wireless signal and the wired signal.

According to one embodiment of the invention, the first signal acquisition sensor is an acceleration sensor and the second signal sensor is an ABS gear tooth pulse sensor.

The tire self-positioning system and the positioning method thereof provided by the invention can improve the success rate of active learning and mainly solve the problem of data deviation caused by reverse movement of the tire.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:

FIG. 1 shows a block flow diagram of a method for self-positioning a tire according to an embodiment of the present invention.

Fig. 2 shows a first flowchart of step S3 in the self-positioning method of the tire according to the embodiment of the present invention.

Fig. 3 shows a block diagram of the flow of step S3 in the self-positioning method of the tire according to the embodiment of the present invention.

Fig. 4 shows a block flow diagram of step S2 of the self-positioning method of the tire according to one embodiment of the present invention.

Fig. 5 shows a schematic structural view of a tire self-positioning system according to an embodiment of the present invention.

FIG. 6 shows an ABS tooth count diagram of an embodiment of the present invention.

Fig. 7 shows a graph of the characteristics of the first signal and the second signal for one embodiment of the invention.

FIG. 8 shows a characteristic graph of ABS encoding and ABS variables for one embodiment of the present invention.

FIG. 9 is a characteristic graph illustrating acceleration of the first signal and ABS tooth count of the second signal in accordance with an embodiment of the present invention.

Fig. 10 shows a schematic diagram of obtaining a reference code value by indexing a second signal code value according to an embodiment of the invention.

FIG. 11 shows an ABS tooth number compensation look-up table according to an embodiment of the present invention.

FIG. 12 shows a first diagram of calculating the compensation value ABS according to an embodiment of the invention.

FIG. 13 shows a second diagram of calculating the compensation value ABS according to an embodiment of the invention.

Fig. 14 shows a first diagram of compensating a reference encoded value according to an embodiment of the present invention.

FIG. 15 shows a second diagram of compensating for a reference encoded value according to an embodiment of the invention.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the application, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The relative arrangement of the components and steps, the numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present application unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

In the description of the present application, it is to be understood that the orientation or positional relationship indicated by the directional terms such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc., are generally based on the orientation or positional relationship shown in the drawings, and are used for convenience of description and simplicity of description only, and in the case of not making a reverse description, these directional terms do not indicate and imply that the device or element being referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore, should not be considered as limiting the scope of the present application; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of protection of the present application is not to be construed as being limited. Further, although the terms used in the present application are selected from publicly known and used terms, some of the terms mentioned in the specification of the present application may be selected by the applicant at his or her discretion, the detailed meanings of which are described in relevant parts of the description herein. Further, it is required that the present application is understood not only by the actual terms used but also by the meaning of each term lying within.

First, the design concept of the tire self-positioning method provided by the invention is briefly explained. Conventionally, a small car is taken as an example, and includes four tires, a Front Left (FL), a Front Right (FR), a Rear Right (RR), and a Rear Left (RL). After the tire condition monitoring system is mounted on each tire, it is necessary to determine the mounting position of the tire air pressure detecting device. During running of the tire, a wireless signal and a wired signal are acquired at the same reference point (the same rotation angle) of any one rotation period. The wireless signal is associated with a reference point for the acceleration signal, and the wired signal includes an ABS signal for a tooth pulse sensor of the tire and a tire position (e.g., FL) where the tooth pulse sensor is known. And calculating actual tooth number information corresponding to the reference point according to the wired signal and the wireless signal, and generating a group of tooth number information queues. For example, the wireless signal of one tire and the wired signal of the front left tire (FL), and the wired signal of the front right tire (FR), and the wired signal of the rear right tire (RR), and the wired signal of the rear left tire (RL) may form a queue of four sets of tooth number information. Based on the statistics, the set of tooth number information having the smallest deviation is determined to be the front left tire (FL) if the wired signal of the front left tire (FL) has the smallest deviation. By analogy, the actual position of each tire condition monitoring system can be confirmed, and therefore the tire position of the tire condition monitoring system can be independently learned.

FIG. 1 shows a block flow diagram of a method for self-positioning a tire according to an embodiment of the present invention. As shown in the figure, the self-positioning method of the tire provided by the invention comprises the following steps:

s1, acquiring data, namely acquiring a wireless signal and a wired signal of the tire, wherein the wireless signal can index the corresponding time when a first signal reaches a reference point, the first signal at least comprises acceleration information of the tire, the wired signal comprises a second signal and corresponding position information of the tire, and the second signal at least comprises rotation angle information of the tire;

s2, converting data, and calculating the reference rotation angle information of the corresponding tire when the first signal reaches a reference point according to the currently received wireless signal and wired signal;

s3, data compensation, if the tire rotates reversely, the reference rotation angle information obtained after the tire rotates reversely is compensated;

s4, carrying out data statistics, repeatedly executing the steps S1 to S3, and carrying out deviation degree statistics on the obtained queue of the reference rotation angle information;

and S5, judging the concrete position of the tire corresponding to the first signal according to the statistical result.

Preferably, the tire rotation angle information includes ABS tooth number of the tire rotation, the wired signal is obtained in step S1, the ABS tooth number is saved, the encoded value is generated, and the plurality of encoded values form an encoded value queue;

in step S2, calculating reference rotation angle information of the tire corresponding to the time when the first signal reaches the reference point according to the currently received wireless signal and wired signal, and recording as a reference encoded value;

in step S3, if there is a reverse rotation of the tire, the reference code value acquired after the reverse rotation of the tire is compensated.

Preferably, in step S3, if there are a plurality of counter rotations of the tire, the reference code value obtained after each counter rotation is compensated.

Preferably, the encoded value includes an ABS tooth number or an ABS angle corresponding to the ABS tooth number, and the conversion formula between the ABS tooth number and the ABS angle is as follows:

absengle (AbsPhyCurrent/ABS _ CODE _ MAXVAL) 360, absengle being the ABS angle, AbsPhyCurrent being the ABS tooth count, ABS _ CODE _ MAXVAL being the tooth count that the ABS increases for one revolution of the tire.

Fig. 2 shows a first flowchart of step S3 in the self-positioning method of the tire according to the embodiment of the present invention. Preferably, as shown, step S3 includes:

s31, recording the number of ABS teeth at the beginning of the reverse motion as AbsStart, and recording the number of ABS teeth at the end of the reverse motion as AbsEnd;

s32, calculating an offset ABS, and if AbsStart is less than or equal to AbsEnd, the offset ABS ═ 2 (AbsEnd-AbsStart) ]% ABS _ CODE _ MAXVAL left; if AbsStart > AbsEnd, the offset ABS ═ ABS _ CODE _ MAXVAL- ([2 × (AbsStart-AbsEnd) ])% ABS _ CODE _ MAXVAL left;

ABS _ CODE _ MAXVAL is the number of teeth that the ABS increases for one tire revolution;

s33, compensating the reference code value acquired after the tire rotates in the reverse direction, and if the current reference code value ABS _ ref is greater than or equal to the compensation value ABS, the compensation reference code value ABS is equal to the reference code value ABS _ ref — the compensation value ABS; if the current reference CODE value ABS _ ref < the compensation value ABS, the compensation reference CODE value ABS is equal to the reference CODE value ABS _ ref + ABS _ CODE _ MAXVAL — the compensation value ABS.

More preferably, step S31 includes:

s311, recording the total tooth number of the ABS when the reverse motion starts, and recording the total tooth number of the ABS when the reverse motion ends, and recording the total tooth number as AbsTotalEnd;

s312, calculating the ABS tooth count at the beginning of the reverse motion, and calculating the ABS tooth count at the end of the reverse motion, where AbsStart ═ AbsTotalStart% ABS _ CODE _ MAXVAL is left, and AbsEnd ═ abstotaltend% ABS _ CODE _ MAXVAL is left.

Fig. 3 shows a block diagram of the flow of step S3 in the self-positioning method of the tire according to the embodiment of the present invention.

Optionally, step S3 includes:

s31', recording the total number of teeth of ABS at the beginning of reverse motion, and recording the total number of teeth of ABS at the end of reverse motion, and recording the total number of teeth of ABS as AbsTotalEnd;

s32', calculating the accumulated increased ABS tooth number abstotaltdeltat-abstotaltstart during the reverse motion;

s33', compensating the reference CODE value acquired after the tire is reversely rotated, the compensation reference CODE value ABS [ reference CODE value ABS _ ref + (ABS _ CODE _ MAXVAL × n) - (2 × abstotalteltadel) ]% ABS _ CODE _ MAXVAL being left;

wherein ABS _ CODE _ MAXVAL is the number of teeth ABS increases for one revolution of the tire, n is an integer, and n is adjusted such that the reference CODE value ABS _ ref + (ABS _ CODE _ MAXVAL × n) is greater than 2 × abstotaltelta.

Preferably, in step S3, if there are n times of reverse rotation of the tire, the method includes the steps of:

recording the total number of ABS teeth at the beginning of the first reverse motion, which is denoted as AbsTotalStart 1, recording the total number of ABS teeth at the end of the first reverse motion, which is denoted as AbsTotalEnd 1, and calculating the number of ABS teeth increased during the first reverse motion, which is AbsTotalDelta 1-AbsTotalStart 1;

according to the steps, recording the number of the ABS teeth increased from the second reverse movement to the nth reverse movement, accumulating the number of the ABS teeth increased from the first reverse movement to the nth reverse movement, and accumulating the increased number of the ABS teeth AbsTotalDelta which is AbsTotalDelta 1+ AbsTotalDelta 2+ … … + AbsTotalDelta n;

correcting the ABS total tooth number AbsTotalAdjusted (reference CODE value ABS _ ref + (ABS _ CODE _ MAXVAL × n) -2 abstotaltelta)% ABS _ CODE _ MAXVAL, n being a natural number, adjusting the value of n so that the reference CODE value ABS _ ref + (ABS _ CODE _ MAXVAL _ n) is greater than 2 abstotaltal delta;

the compensation reference CODE value ABS is obtained by the remainder of the correction ABS total tooth number AbsTotalAdjusted% ABS _ CODE _ MAXVAL;

the reference encoding value ABS _ ref is compensated by compensating the reference encoding value ABS.

Fig. 4 shows a block flow diagram of step S2 of the self-positioning method of the tire according to one embodiment of the present invention. Preferably, step S2 includes:

s21, recording the time interval T1 of the currently received wireless signal and wired signal;

s22, obtaining the backtracking time T2 from the first signal reaching the reference point to the wireless signal receiving;

s23, indexing time T3 ═ backtracking time T2-time interval T1;

s24, calculating the number of code values needed to index back, wherein the number is the index time T3/the cycle ABS _ period of the second signal;

s25, recording the encoding value ABS _ search indexed in the queue of encoding values according to the number of the backward indexes;

s26, the encoding value ABS _ search is corrected, and the reference encoding value ABS _ ref is obtained.

Preferably, step S26 includes:

s261, calculating a time interval Δ T between the encoded value ABS _ search and ABS _ ref as a correction index time T3% of the period ABS _ period of the second signal to be left;

s262, calculate the difference between the reference encoded value ABS _ ref and the encoded value ABS _ search: the difference Δ ABS ═ Δ T/ABS _ period (ABS [ n-index back-index number ] -ABS [ n-index back-index number-1 ]);

s263, calculate a reference code value ABS _ ref — ABS [ n-index back ] - [ Δ ABS for the tire where the first signal reaches the reference point.

Preferably, the backtracking time T2 is a fixed value, or a specific value calculated by a specific algorithm.

Preferably, the characteristic curve of the first signal is a sinusoidal curve, and a specific angle of the first signal is selected as a reference point. From the characteristic curve of the first signal, the position of a reference point is determined, which may be the highest point, the lowest point of the characteristic curve of the first signal, or the position of the tire in contact with the ground, or any other angular position. Preferably, the highest point of the sinusoid of the first signal is selected as a reference point for the data transition.

Fig. 5 shows a schematic structural view of a tire self-positioning system according to an embodiment of the present invention. As shown, the present invention also provides a tire self-positioning system 400 for performing the aforementioned tire self-positioning method. The tire self-positioning system 400 basically includes a tire 401, a tire condition detecting device 402, a second signal sensor 403, a second signal controller 404, a communication bus 405 and a signal receiving processor 406.

Here, the tire condition detection device 402 and the second signal sensor 403 are provided on the tire 401. The tire condition sensing device 402 is configured to collect the first signal and the pressure, temperature, and identification code of the tire and generate a wireless signal.

The second signal sensor 403 is used to acquire a second signal.

The second signal controller 404 is electrically connected to the second signal sensor 403. The second signal controller 404 receives the second signal and generates a wired signal, where the wired signal includes an encoded value corresponding to the second signal and position information of the tire where the second signal sensor is located.

The signal reception processor 406 receives a wired signal through the communication bus 405. The signal reception processor 406 simultaneously receives wireless signals. The signal receiving processor 406 performs steps S2 to S4 in the tire self-positioning method according to the wireless signal and the wired signal, and finally determines a specific position of the tire corresponding to the first signal of the reference point. In an embodiment, the communication bus 405 may be a CAN communication bus.

Preferably, the tire condition detecting device 402 includes a first signal collecting sensor for collecting a first signal and a wireless transmitting circuit, and the generated wireless signal is transmitted to the signal receiving processor 406 through the wireless transmitting circuit. Generally, the tire condition detecting device 402 is mounted in a tire. The tire condition detection device 402 further includes a tire air pressure sensor, a temperature sensor, and the like. The tire condition detection device 402 can process the tire condition information collected by each sensor through a micro control unit integrated on a chip thereof, and simultaneously combine the collected tire pressure value, temperature value and the like into a wireless signal, and simultaneously cooperate with a wireless transmitting circuit to send out the wireless signal.

Preferably, the first signal acquisition sensor is an acceleration sensor, and the second signal sensor 403 is an ABS gear pulse sensor of an anti-lock braking system. As the tire 401 rotates, the first signal exhibits a sinusoidal characteristic. Conventionally, a vehicle is provided with a plurality of tires 401, and in the present embodiment, the vehicle has 4 tires 401, which are a front left tire (FL), a front right tire (FR), a rear right tire (RR), and a rear left tire (RL). Each tire is provided with a tire condition detecting device 402, and each tire condition detecting device 402 has a unique identifier, referred to as the ID of the tire condition detecting device 402. By way of example and not limitation, the wireless signals transmitted by the tire condition detecting device 402 include an identifier, pressure, transmission time, and the like. Further, when the tire 401 rolls, the gear of the anti-lock brake system rolls along with the tire 401, and the pulse sensor of the teeth of the ABS gear collects the number of the rotating teeth of the ABS and sends the information of the number of the teeth of the ABS gear. And coding the ABS tooth number information to form a coded value. FIG. 6 shows an ABS tooth count diagram of an embodiment of the present invention. As shown, starting with the forward X-axis as the minimum CODE ABS _ CODE _ MIN, the CODE increases by 1 tooth for every 1 tooth of tire rotation counterclockwise until the CODE reaches the maximum value ABS _ CODE _ MAX after one cycle of tire rotation, after which the CODE begins again with the minimum CODE. In the embodiment, the number of teeth of the gear teeth is 48, that is, ABS _ CODE _ MIN is 0; ABS _ CODE _ MAX is 47, which produces one pulse per tooth of tire 401, so that tire 401 produces 48 pulses per revolution and 96 pulses per 2 revolutions. Since the tire condition sensing device 402 and the gear in the same location are rolling along with the tire and they are coaxial, the characteristic curves of the first and second signals remain synchronized at all times. Fig. 7 shows a graph of the characteristics of the first signal and the second signal for one embodiment of the invention. As shown, the first signal (acceleration signal) characteristic curve is shown above, and the second signal (ABS tooth code signal) characteristic curve is shown below, both synchronized.

The second signal controller 404 receives the ABS tooth number data output from the second signal sensor 403 and stores the ABS tooth number data in an accumulated form to an internal variable, which is counted again from the minimum value ABS _ MIN of the ABS variable after being accumulated to the maximum value ABS _ MAX of the ABS variable. The second signal controller 404 processes the ABS variable into a data format conforming to the bus protocol for substantially periodic transmission onto the bus. FIG. 8 shows a characteristic graph of ABS code values and ABS variables for one embodiment of the present invention. The corresponding relation between the ABS code value and the ABS variable is as follows: ABS CODE value ═ (ABS variable)% ABS _ CODE _ MAX. For example: the value range of the ABS coded value can be 0-47; the ABS variable may range from 0 to 47.

The signal receiving processor 406 is disposed on the vehicle body side, and is configured to receive a wireless signal from each tire condition detection device 402 at an arbitrary random timing. The signal receiving processor 406 receives the wired signal including the second signal, which is substantially periodic, from the second signal controller 404, in this embodiment the wired signal includes the second signal at four positions FL/FR/RR/RL.

Preferably, the trace-back time T2 is a fixed value and is included in the wireless signal. The trace-back time T2 may also be calculated by the tire condition detection device 402 and the signal reception processor 406 through the same specific algorithm to obtain a specific value. Specifically, an arbitrary angle of the first signal is selected as a reference point for data conversion, and a trace-back time T2 is set between the transmission time and the reception time of the wireless signal. The backtracking time T2 may be generated by a specific algorithm, i.e., an agreed backtracking time. The same algorithm is executed on the tire condition detection device 402 and the signal reception processor 406, and finally, a synchronized backtracking time T2 is obtained on the tire condition detection device 402 and the signal reception processor 406. The specific value may be calculated from the pressure, temperature or identification code of the tire. For example, the wireless signal includes the tire pressure information including the pressure P, the temperature T, and the ID of the tire condition monitoring device, and the back tracking time T2 is sum (P + T + ID0+ ID1+ ID2+ ID3), thereby forming an agreed back tracking time.

FIG. 9 is a characteristic graph illustrating acceleration of the first signal and ABS tooth count of the second signal in accordance with an embodiment of the present invention. As shown, since the tire condition detection device 402 and the tire 401 at the same position are coaxial, the acceleration characteristic curve of the first signal from the tire condition detection device 402 at the upper side in fig. 11 and the acceleration characteristic curve of the second signal at the lower side show a synchronous law. By using this characteristic, if the reference point is selected at the same angle of the first signal characteristic curve, the corresponding coaxial second signal code values are aggregated at a specific value. The dashed position in the figure is the highest point of the sinusoid of the selected first signal as the reference point. Since the wired signal includes the rotation angle information of the second signal, that is, the ABS tooth number information, the position of the tire condition detection device 402 can be identified by using the known rotation angle information of the second signal and the relationship between the first signal characteristic curve and the second signal characteristic curve in synchronization.

Fig. 10 shows a schematic diagram of obtaining a reference code value by indexing a second signal code value according to an embodiment of the invention. As shown, Receive _ RF is the current wireless signal received by the signal receiving processor 406, and ABS _ ref is the reference encoding value at which the first signal reaches the reference point. T2 is a trace-back time, which is the time interval between the currently received radio signal Receive _ RF and the first signal reaching the reference point, and it can be included in the radio signal or obtained by calculation in the form of a time stamp. As shown in the figure, the encoded value of the second signal of the currently obtained wired signal is denoted as ABS [ n ], as a starting point, indexed back, and the reference encoded value ABS _ Ref at the reference point is calculated. The reference code value is obtained as described in detail with reference to fig. 6.

The corresponding reference encoded value at the reference point may be indexed by:

s21, recording the time interval T1 of the current wireless signal and wired signal reception.

S22, obtaining the backtracking time T2 from the first signal reaching the reference point to the wireless signal receiving; .

S23, index time T3 ═ transmission time T2-time interval T1, which is the time from the reference point to ABS [ n ].

S24, calculating the number of code values needed to index back, wherein the number is the index time T3/the period ABS _ period of the cable signal, and the index value of the code value queue needed to be calculated.

S25, recording the code value ABS _ search indexed in the queue of code values according to the number of indexes back, in this example, the code value ABS _ search of the second signal is ABS [ n-2]

S26, the encoding value ABS _ search is corrected, and the reference encoding value ABS _ ref is obtained.

Specifically, step S26 includes:

s261, calculate the time interval Δ T between ABS _ search and ABS _ ref as the correction index time T3% of the period ABS _ period of the second signal

S262, calculate the difference between ABS _ ref and ABS _ search (ABS tooth count difference between them): Δ ABS ═ Δ T/ABS _ period (ABS [ n-2] -ABS [ n-3])

And S263, correcting the reference code value at the corresponding reference point, and acquiring the reference code value ABS _ ref which is ABS [ n-2] -. DELTA.ABS.

As will be readily understood, the signal reception processor 406 executes the steps S21 to S26 more than once each time it receives a wireless signal from one tire condition detection device 402, and can obtain a queue of the reference code value ABS _ ref accumulated for each tire condition detection device 402. Taking 4 tires equipped with 4 tire condition detecting devices 402 as an example, each tire corresponds to 4 sets of reference code value ABS _ ref data. There are 16 sets of reference code values ABS _ ref data for 4 tires. The data deviation degree is analyzed for 4 sets of reference code values ABS _ ref corresponding to each tire, and the minimum value of the variance is determined as the minimum deviation degree.

During active learning of the tire self-alignment system, the number of pulses of the ABS is increased regardless of whether the vehicle is running in the forward direction or in the reverse direction, resulting in an increase in the number of teeth of the ABS. The ABS corresponding to the tire self-alignment system converges near n teeth when no reverse motion occurs, but when the vehicle travels in reverse for some distance and then travels in forward direction, the number of teeth of the set of ABS converges (n teeth ± compensation ABS), which is the relative offset of the ABS caused by reverse.

FIG. 11 shows an ABS tooth number compensation look-up table according to an embodiment of the present invention. As shown in the figure, when the vehicle is traveling normally upward, the ABS converges to around 14, and when the vehicle is traveling again in the forward direction after the reverse direction has occurred, the ABS converges to around 32. The relative offset of the ABS during reverse travel can be calculated as 18 teeth, compensating for the offset, and the compensated ABS in the next figure re-converges to about 14. Specifically, the offset amount of the reference code value is compensated during the reverse travel, so that the queue of the reference code value is kept converged.

FIG. 12 shows a first diagram of calculating the compensation value ABS according to an embodiment of the invention. As shown, if AbsStart ≦ AbsEnd, the offset ABS ═ 2 (AbsEnd-AbsStart) ]% ABS _ CODE _ MAXVAL is left. FIG. 13 shows a second diagram of calculating the compensation value ABS according to an embodiment of the invention. If AbsStart > AbsEnd, the offset ABS ═ ABS _ CODE _ MAXVAL- ([2 × (AbsStart-AbsEnd) ])% ABS _ CODE _ MAXVAL.

The reference code value acquired after the tire is reversely rotated is compensated based on the compensation value ABS. Fig. 14 shows a first diagram of compensating a reference encoded value according to an embodiment of the present invention. If the current reference code value ABS _ ref is greater than or equal to the compensation value ABS, the compensation reference code value ABS is equal to the reference code value ABS _ ref — the compensation value ABS. FIG. 15 shows a second diagram of compensating for a reference encoded value according to an embodiment of the invention. If the current reference CODE value ABS _ ref < the compensation value ABS, the compensation reference CODE value ABS is equal to the reference CODE value ABS _ ref + ABS _ CODE _ MAXVAL — the compensation value ABS.

It is easy to understand that the ABS tooth number and the ABS angle can be converted to each other, the compensation value ABS can also be calculated by the ABS angle, and the conversion formula of the ABS tooth number and the ABS angle is as follows:

absengle (AbsPhyCurrent/ABS _ CODE _ MAXVAL) 360, absengle being the ABS angle, AbsPhyCurrent being the ABS tooth count, ABS _ CODE _ MAXVAL being the tooth count that the ABS increases for one revolution of the tire.

Referring to the ABS tooth number compensation step, the angle AngleStart, AngleStart ═ (AbsStart/ABS _ CODE _ MAXVAL) × 360 at the beginning of the calculation of the reverse motion. The angle AngleEnd at the end of the reverse motion is calculated, AngleEnd ═ (AbsEnd/ABS _ CODE _ MAXVAL) × 360. By analogy, the ABS angle can also be used to compensate the reference encoded value, which is not described herein.

It is emphasized that if there are multiple counter-rotations of the tire, the reference code values obtained after each counter-rotation are compensated for to ensure the accuracy of the data statistics.

In order to save the power consumption, the time for the signal reception processor 406 to execute the tire condition ID learning process is controlled within 10 min. In the learning mode, the tire condition detecting device transmits 40 packets of wireless signals each including 3 frames of data, each of which can be indexed to the position of the reference point. The interval between the packets is 15s, and the frame interval in each packet is random time of 60-200 ms. The random frame interval mechanism is adopted, so that the position of the wireless signal to be transmitted is randomly changed, and the probability of the wireless signal to be received can be improved.

It should be noted that the signal receiving processor 406 may record the total tooth number abstotaltstart of ABS at the beginning of reverse motion, and accumulate the total tooth number abstotaltstart from the beginning of reverse vehicle start. The total tooth number abstotaltend of the ABS at the end of the reverse motion is recorded and accumulated since the vehicle ended the reverse motion. The relative ABS tooth number AbsStart ═ AbsTotalStart% ABS _ CODE _ MAXVAL at the beginning of reverse motion is calculated. The relative ABS tooth number AbsEnd ═ AbsTotalEnd% ABS _ CODE _ MAXVAL at the end of the reverse motion is calculated.

It will be apparent to those skilled in the art that various modifications and variations can be made to the above-described exemplary embodiments of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.