Tire temperature and pressure monitoring system based on sensor data

Abstract

The present invention relates to the field of data processing, and in particular to a tire temperature and pressure monitoring system based on sensor data. The system includes: an acquisition module, a rejection module, an interception module and an evaluation module; the acquisition module is used to acquire tire temperature sequences, tire pressure sequences and suspension height sequences; the rejection module is connected to the acquisition module and is used to eliminate abnormal tire temperatures and tire pressures in the tire temperature sequences and tire pressure sequences to form new tire temperature sequences and tire pressure sequences; the interception module is connected to the rejection module and is used to calculate the optimal window width according to the new tire temperature sequence, and intercept the last window in the new tire pressure sequence as the optimal window according to the optimal window width; the evaluation module is connected to the interception module and is used to calculate the tire pressure score for the optimal window, and when the tire pressure score is greater than a threshold value, the tire pressure is abnormal. The present invention effectively solves the problem of inaccurate judgment of abnormal tire pressure in the prior art.

Description

Technical Field

[0001] The present invention relates to the field of data processing, and more specifically, to a tire temperature and pressure monitoring system based on sensor data. Background Art

[0002] Since tires are an important part of the vehicle's running mechanism, they not only carry the entire mass of the vehicle, but also provide propulsion for the vehicle to move forward and mitigate ground impact. The tire pressure monitoring system can monitor the tires in real time, reminding the driver of possible safety hazards and preventing accidents in advance.

[0003] The tire pressure monitoring system mainly consists of two parts. One part is the sensor installed inside the tire, which can be fixed on the wheel hub through the valve stem to monitor the temperature, pressure and acceleration of the tire in real time. The second part is the receiver, which is installed in a position in the cockpit that is easy for the driver to observe (some are directly displayed by the instrument), which can display the current tire pressure, temperature and fault conditions, so that the driver can understand the condition of the tire. The signal transmission between the sensor and the receiver is carried out through high-frequency wireless signals. The sensor installed in the tire can continuously measure the pressure and temperature of the tire, and through analysis, it can be determined whether the tire pressure is abnormal; if the tire pressure is found to be abnormal, the result will be sent to the receiver through a high-frequency wireless signal, and the receiver will remind the driver of the tire fault through sound and light alarm.

[0004] At present, a Chinese patent document with authorization announcement number CN110481249B discloses a tire pressure slow leakage detection method and a tire pressure detection device. The system acquires tire status data in real time and forms a tire pressure status table, wherein the tire status data includes collection time, current tire pressure value and current tire temperature value matching the current tire pressure value; based on the sampled tire pressure value, a sampled tire temperature value matching the sampled tire pressure value is acquired from the tire pressure status table; a current tire pressure value group matching the sampled tire temperature value in the tire pressure status table is determined, and the difference between the current tire temperature corresponding to the current tire pressure value in the current tire pressure value group and the sampled tire temperature value meets a preset temperature threshold; a slow leakage detection ratio is calculated, and if the slow leakage detection ratio is greater than the preset threshold, a slow tire leakage is determined.

[0005] In real life, abnormal tire pressure and temperature data may occur due to road conditions, weather and other reasons, and the changes in tire temperature and pressure are different at different times or in different weather conditions. The above method only matches the current tire pressure value group that is compatible with the sampled tire temperature value, which can easily lead to inaccurate judgment of abnormal tire pressure. Summary of the invention

[0006] In order to solve the problem of inaccurate judgment of abnormal tire pressure in the prior art, the present invention provides the following solution.

[0007] The present invention provides a tire temperature and tire pressure monitoring system based on sensor data, comprising: an acquisition module, used for acquiring a tire temperature sequence, a tire pressure sequence and a suspension height sequence; a rejection module, connected to the acquisition module, used for rejecting abnormal tire temperatures and tire pressures in the tire temperature sequence and tire pressure sequence to form a new tire temperature sequence and tire pressure sequence; an interception module, connected to the rejection module, used for calculating an optimal window width according to the new tire temperature sequence, and intercepting the last window in the new tire pressure sequence as the optimal window according to the optimal window width; an evaluation module, connected to the interception module, used for calculating a tire pressure score for the optimal window, when the tire pressure score is greater than a threshold value, the tire pressure is abnormal; calculating the optimal window width according to the new tire temperature sequence, comprising: calculating a window interception coefficient corresponding to different window widths ,in, is the window width, , k is the current time, a is the start time of the window, b is the end time of the window, is the tire temperature stability index corresponding to the window [a, b]; construct a truncation coefficient sequence according to the window truncation coefficients corresponding to different window widths, obtain a nonlinear fitting curve of the truncation coefficient sequence, and take the window width corresponding to the first minimum value of the second-order derivative of the nonlinear fitting curve as the optimal window width; is the mean absolute deviation of the first sequence, which is composed of the ratio of the tire temperature at each moment to the previous moment in the window [a, b].

[0008] By eliminating abnormal data, optimizing window width selection and tire pressure scoring system, the present invention can more accurately capture the dynamic changes of tire temperature and tire pressure, reducing misjudgments and missed judgments. The tire pressure scoring based on the optimal window and the nonlinear fitting analysis method can effectively improve the detection sensitivity of abnormal tire pressure and avoid safety risks caused by abnormal tire pressure. In summary, this tire temperature and tire pressure monitoring system can effectively improve the accuracy of abnormal tire pressure monitoring through precise window analysis and abnormality detection methods, further enhancing the safety and reliability of the vehicle.

[0009] Preferably, the method of eliminating abnormal tire temperature and tire pressure in the tire temperature sequence and tire pressure sequence specifically includes: presetting the window width , divide the hanging height sequence into windows and calculate the rejection coefficient of each window , the elimination coefficient When it is greater than the threshold, the tire temperature and tire pressure corresponding to the i-th window are eliminated. ,in, It means to find the maximum value, Indicates the preset window width, represents the mth hanging height in the ith window, Represents the mean hanging height in the i-th window.

[0010] By dividing the suspension height sequence and calculating the elimination coefficient, it is possible to effectively identify abnormal changes in tire temperature and tire pressure data when there is a problem with the suspension system. Since abnormal fluctuations in the suspension system are often related to changes in tire pressure and tire temperature, eliminating these abnormal data can avoid misjudgments caused by suspension abnormalities. For example, when the vehicle's suspension height changes greatly on a rough road, the tire pressure also changes greatly in this case, but the tire pressure data at this time is not reliable and therefore needs to be eliminated.

[0011] Preferably, the calculation of the tire pressure score for the optimal window specifically includes: calculating the tire pressure ratio between each moment in the optimal window and the previous moment, the tire pressure ratio constituting a second sequence; performing Otsu threshold segmentation on the second sequence to obtain the front and rear parts of the optimal segmentation, respectively calculating the means of the two parts to obtain the front mean and the rear mean, and taking the ratio of the absolute difference between the front mean and the rear mean to the front mean as the tire pressure score.

[0012] By calculating the change in tire pressure ratio and using the Otsu threshold segmentation method, abnormal tire pressure fluctuations can be identified more accurately. This method can automatically adapt to the changing characteristics of different tire pressure data and improve the sensitivity of detection. The application of the Otsu method reduces the intervention of manually setting thresholds and avoids the subjective bias that may exist in traditional methods by adaptively dividing the front and back parts of the data. By calculating the tire pressure ratio, applying the Otsu threshold segmentation, and calculating the difference between the front and back means, the present invention provides a sensitive, accurate, and automated tire pressure anomaly detection method.

[0013] Preferably, said dividing the hanging height sequence into windows comprises: using a sliding window method to divide the hanging height sequence into windows.

[0014] The sliding window method is suitable for real-time data processing. By analyzing the hanging height in each window, the location of the anomaly can be accurately located to avoid eliminating more reliable data.

[0015] Preferably, the tire temperature and pressure monitoring system based on sensor data further includes: a storage module for storing tire temperature sequences, tire pressure sequences and suspension height sequences at historical moments.

[0016] Preferably, the acquisition module comprises: utilizing a temperature sensor, a pressure sensor and a suspension height sensor to acquire a tire temperature sequence, a tire pressure sequence and a suspension height sequence.

[0017] Preferably, the tire temperature and pressure monitoring system based on sensor data further includes: an early warning module for issuing an early warning through the color of a fault warning light and / or the sound of a fault warning bell when abnormal tire pressure is detected.

[0018] Through timely visual and auditory warnings, drivers can quickly detect abnormal tire pressure and take necessary measures, thereby reducing the risk of traffic accidents caused by abnormal tire pressure and ensuring driving safety.

[0019] Preferably, the tire temperature and pressure monitoring system based on sensor data further includes: a display module for displaying tire temperature, tire pressure, suspension height and tire pressure score in real time.

[0020] The beneficial effects of the present invention are as follows: by eliminating abnormal data, optimizing window width selection and tire pressure scoring system, the present invention can more accurately capture the dynamic changes of tire temperature and tire pressure, and reduce misjudgments and missed judgments. The tire pressure scoring based on the optimal window and the nonlinear fitting analysis method can effectively improve the detection sensitivity of abnormal tire pressure and avoid safety risks caused by abnormal tire pressure. In summary, this tire temperature and tire pressure monitoring system can effectively improve the accuracy of abnormal tire pressure monitoring through precise window analysis and abnormality detection methods, and further enhance the safety and reliability of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] By reading the following detailed description with reference to the accompanying drawings, the above and other objects, features and advantages of the exemplary embodiments of the present invention will become readily understood. In the accompanying drawings, several embodiments of the present invention are shown in an exemplary and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0022] Figure 1 is a schematic diagram of a tire temperature and pressure monitoring system based on sensor data provided by an embodiment of the present invention;

[0023] Figure numerals: 1. acquisition module; 2. elimination module; 3. interception module; 4. evaluation module. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0025] The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0026] Figure 1 is a schematic diagram of a tire temperature and pressure monitoring system based on sensor data according to an embodiment of the present invention.

[0027] like Figure 1As shown, the tire temperature and pressure monitoring system based on sensor data provided by the embodiment of the present invention includes: a collection module 1, a rejection module 2, an interception module 3 and an evaluation module 4;

[0028] The acquisition module 1 is used to acquire tire temperature sequence, tire pressure sequence and suspension height sequence.

[0029] During vehicle driving, tire pressure will affect driving safety, so the tire pressure sequence must be collected in the present invention. Because tire temperature and suspension height will have a certain impact on tire pressure, tire temperature sequence and suspension height sequence also need to be collected.

[0030] In some embodiments, a temperature sensor, a pressure sensor, and a suspension height sensor may be generally used to collect a tire temperature sequence, a tire pressure sequence, and a suspension height sequence.

[0031] Since the tire temperature, tire pressure and suspension height at historical moments are used in the system, a storage module is generally required to store these data.

[0032] The elimination module 2 is connected to the acquisition module 1 and is used to eliminate abnormal tire temperatures and tire pressures in the tire temperature sequence and tire pressure sequence to form a new tire temperature sequence and tire pressure sequence.

[0033] The suspension height sequence can generally reflect the ruggedness of the road. If the road is relatively rugged, the tire pressure will change larger and faster. The tire pressure in this case is an unreliable abnormal tire pressure, so it is necessary to eliminate the abnormal tire pressure under rugged roads. Tire temperature and tire pressure are closely related. Changes in tire temperature often affect tire pressure, so it is also necessary to eliminate the abnormal tire temperature under rugged roads.

[0034] In some embodiments, the method of eliminating abnormal tire temperatures and tire pressures in the tire temperature sequence and tire pressure sequence specifically includes: a preset window width , divide the hanging height sequence into windows and calculate the rejection coefficient of each window , the elimination coefficient When it is greater than the threshold, the tire temperature and tire pressure corresponding to the i-th window are eliminated. ,in, It means to find the maximum value, Indicates the preset window width, represents the mth hanging height in the ith window, represents the mean value of the hanging height in the ith window. The step of dividing the hanging height sequence into windows comprises: dividing the hanging height sequence into windows by using a sliding window method.

[0035] For example, the tire temperature sequence, tire pressure sequence and suspension height sequence collected over a period of time are: , and , the preset window width is 3, then the hanging height sequence can be divided into 4 windows using the sliding window method: , , , , calculated , and is less than the threshold, is greater than the threshold, so the tire temperature and tire pressure corresponding to the second window are eliminated, that is, the tire temperature sequence is eliminated. and , in the tire pressure sequence and , and then a new tire temperature sequence is formed: , the new tire pressure sequence is .

[0036] The interception module 3 is connected to the rejection module 2 and is used to calculate the optimal window width according to the new tire temperature sequence, and intercept the last window in the new tire pressure sequence as the optimal window according to the optimal window width;

[0037] Tire temperature and tire pressure are closely related, and changes in tire temperature often affect tire pressure. For example, when tire temperature changes stably, tire pressure changes are also stable under normal circumstances. When tire temperature changes are unstable, tire pressure changes are also unstable. Therefore, the true tire pressure situation cannot be analyzed when tire temperature changes are unstable. Therefore, by analyzing the changes in the tire temperature sequence, the window width in which the tire temperature changes are relatively stable is found, and the last window in the new tire pressure sequence is intercepted with this window width as the optimal window. The tire pressure in this optimal window is the most reliable and can best reflect the true tire pressure situation. If the tire pressure changes stably in this optimal window, then the tire pressure is normal. If the tire pressure changes unstable in this optimal window, then the tire pressure is abnormal.

[0038] In some embodiments, calculating the optimal window width according to the new tire temperature sequence includes: calculating the window interception coefficient corresponding to different window widths ,in, is the window width, , k is the current time, a is the start time of the window, b is the end time of the window, is the tire temperature stability index corresponding to the window [a, b]; a truncation coefficient sequence is constructed according to the window truncation coefficients corresponding to different window widths, a nonlinear fitting curve of the truncation coefficient sequence is obtained, and the window width corresponding to the first minimum value of the second-order derivative of the nonlinear fitting curve is taken as the optimal window width.

[0039] Above is the mean absolute deviation of the first sequence, which consists of the ratio of the tire temperature at each moment in the window [a, b] to the previous moment. Since there is no tire temperature at the previous moment corresponding to the first tire temperature in the window [a, b], the tire temperature at the previous moment closest to the first tire temperature outside the window [a, b] can be used to calculate the corresponding tire temperature ratio. For example, the tire temperature sequence of the window [a, b] is , outside the window [a,b] and The tire temperature at the most recent moment is , then the first sequence is The following calculation of the mean absolute deviation of the first sequence is a well-known method and will not be described in detail here.

[0040] For example, if there are 8 tire temperature data in the new tire temperature sequence, then , for each window width, there is a corresponding window interception coefficient. All window interception coefficients are combined into a window interception coefficient sequence, and the nonlinear fitting curve of this window interception coefficient sequence is obtained. The window width corresponding to the first minimum of the second-order derivative of the nonlinear fitting curve is the optimal window width. The above process can directly put the window interception coefficient sequence into matlab for nonlinear fitting and calculate the first minimum of the second-order derivative of the nonlinear fitting curve. It will not be repeated here. The optimal window is the window whose window width is the optimal window width, and the end of the window is the window composed of the last tire pressure in the new tire pressure sequence.

[0041] The evaluation module 4 is connected to the interception module 3 and is used to calculate the tire pressure score for the optimal window. When the tire pressure score is greater than a threshold, the tire pressure is abnormal.

[0042] When abnormal tire pressure is detected, in order to ensure that the driver can quickly detect the abnormality and take necessary measures to ensure driving safety, an early warning module is also required in the system to issue an early warning through the color of the fault warning light and / or the sound of the fault warning bell when abnormal tire pressure is detected.

[0043] In some special cases, the system may not be able to provide reliable abnormal evaluation or abnormal warning. At this time, it is necessary to display the tire temperature, tire pressure, suspension height and tire pressure score in real time. The driver relies on his own experience to judge whether the tire pressure is abnormal based on these data.

[0044] In some embodiments, the calculation of the tire pressure score for the optimal window specifically includes: calculating the tire pressure ratio between each moment in the optimal window and the previous moment, the tire pressure ratio constituting a second sequence; performing Otsu threshold segmentation on the second sequence to obtain the front and rear parts of the optimal segmentation, respectively calculating the means of the two parts to obtain the front mean and the rear mean, and taking the ratio of the absolute difference between the front mean and the rear mean to the front mean as the tire pressure score.

[0045] The tire pressure ratio of each moment in the optimal window to the previous moment. Since there is no tire pressure at the previous moment corresponding to the first tire pressure in the optimal window, the tire pressure at the previous moment closest to the first tire pressure outside the optimal window can be used to calculate the corresponding tire pressure ratio. For example, the new tire pressure sequence is , the optimal window is , then the second sequence is The second sequence is segmented by Otsu threshold, and a threshold T can be calculated. The data in the second sequence whose tire pressure ratio is less than the threshold T constitutes the front part, and the mean of the front part is the front mean. , the data greater than the threshold T constitutes the rear part, and the mean of the rear part is the rear mean , tire pressure score When the tire pressure score is greater than a threshold, the tire pressure is abnormal. The threshold can be set to 0.1 under normal circumstances. The Otsu threshold segmentation is a well-known technology and will not be described in detail here.

[0046] The embodiment of the present invention provides a tire temperature and pressure monitoring system based on sensor data. By eliminating abnormal data, optimizing window width selection and tire pressure scoring system, the present invention can more accurately capture the dynamic changes of tire temperature and tire pressure and reduce misjudgments and missed judgments. The tire pressure scoring based on the optimal window and the nonlinear fitting analysis method can effectively improve the detection sensitivity of abnormal tire pressure and avoid safety risks caused by abnormal tire pressure. In summary, this tire temperature and pressure monitoring system can effectively improve the accuracy of abnormal tire pressure monitoring and further enhance the safety and reliability of the vehicle through precise window analysis and abnormality detection methods.

[0047] In the description of this specification, "plurality" or "several" means at least two, such as two, three or more, etc., unless otherwise clearly and specifically defined.

[0048] Although this specification has shown and described a number of embodiments of the present invention, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Those skilled in the art will conceive of many modifications, changes and alternatives without departing from the ideas and spirit of the present invention. It should be understood that in the practice of the present invention, various alternatives to the embodiments of the present invention described herein may be employed.

Claims

1. A tire temperature and pressure monitoring system based on sensor data, characterized in that: include: A collection module, used to collect tire temperature sequence, tire pressure sequence and suspension height sequence; The elimination module is connected to the acquisition module and is used to eliminate abnormal tire temperatures and tire pressures in the tire temperature sequence and tire pressure sequence to form a new tire temperature sequence and tire pressure sequence, including: a preset window width , divide the hanging height sequence into windows and calculate the rejection coefficient of each window , the elimination coefficient When it is greater than the threshold, the tire temperature and tire pressure corresponding to the i-th window are eliminated. ,in, It means to find the maximum value, Indicates the preset window width, represents the mth hanging height in the ith window, represents the mean of the hanging height in the i-th window; A capture module, connected to the rejection module, for calculating an optimal window width according to the new tire temperature sequence, and capturing the last window in the new tire pressure sequence as the optimal window according to the optimal window width; An evaluation module, connected to the interception module, for calculating a tire pressure score for the optimal window, and when the tire pressure score is greater than a threshold, the tire pressure is abnormal; Calculating the optimal window width according to the new tire temperature sequence includes: calculating the window interception coefficient corresponding to different window widths ,in, is the window width, , k is the current time, a is the start time of the window, b is the end time of the window, is the tire temperature stability index corresponding to the window [a, b]; construct a truncation coefficient sequence according to the window truncation coefficients corresponding to different window widths, obtain a nonlinear fitting curve of the truncation coefficient sequence, and take the window width corresponding to the first minimum value of the second-order derivative of the nonlinear fitting curve as the optimal window width; is the mean absolute deviation of the first sequence, which is composed of the ratio of the tire temperature at each moment to the previous moment in the window [a, b].

2. The tire temperature and pressure monitoring system based on sensor data according to claim 1, characterized in that: The step of calculating the tire pressure score for the optimal window specifically includes: Calculating the tire pressure ratio between each moment and the previous moment in the optimal window, wherein the tire pressure ratios constitute a second sequence; The second sequence is segmented by Otsu threshold to obtain the front and rear parts of the optimal segmentation, the means of the two parts are calculated respectively to obtain the front mean and the rear mean, and the ratio of the absolute difference between the front mean and the rear mean to the front mean is used as the tire pressure score.

3. The tire temperature and pressure monitoring system based on sensor data according to claim 1, characterized in that: The step of dividing the suspension height sequence into windows comprises: The hanging height sequence is divided into windows using a sliding window method.

4. The tire temperature and pressure monitoring system based on sensor data according to claim 1, characterized in that: Also includes: The storage module is used to store tire temperature sequences, tire pressure sequences and suspension height sequences at historical moments.

5. The tire temperature and pressure monitoring system based on sensor data according to claim 1, characterized in that: The acquisition module comprises: The temperature sensor, pressure sensor and suspension height sensor are used to collect tire temperature sequence, tire pressure sequence and suspension height sequence.

6. The tire temperature and pressure monitoring system based on sensor data according to claim 1, characterized in that: Also includes: The early warning module is used to issue an early warning through the color of the fault warning light and / or the sound of the fault warning bell when abnormal tire pressure is detected.

7. The tire temperature and pressure monitoring system based on sensor data according to claim 1, characterized in that: Also includes: The display module is used to display tire temperature, tire pressure, suspension height and tire pressure score in real time.

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