A method and device for automatic detection of alcohol sensor failure

Abstract

The application provides an alcohol sensor fault automatic detection method and device, and belongs to the technical field of alcohol sensor fault detection. First, the alcohol sensor is tested by using a set test source, a test curve reflecting alcohol content is obtained, and then any index of the curve peak value of the test curve, the curve peak value reaching time, the curve tailing time length, the curve peak value rising slope and the curve falling slope is judged. When any index meets the corresponding fault judgment condition, whether the alcohol sensor has a fault is judged. The method can detect whether the alcohol sensor has a fault at any time by using the test source, improves the fault detection efficiency, and also ensures the accuracy of the detection result.

Description

Technical Field

[0001] This invention relates to an automatic detection method and device for alcohol sensor faults, belonging to the field of alcohol sensor fault detection technology. Background Technology

[0002] To prevent drunk driving and avoid traffic accidents caused by it, breathalyzers are commonly used to test drivers for alcohol. The results of these tests serve as the standard for determining whether a driver has consumed alcohol. The alcohol sensor, as the core component of the breathalyzer, directly affects the final result. If the sensor malfunctions, it can lead to incorrect readings and misjudgments—for example, detecting alcohol in a person who hasn't drunk and vice versa. This will affect testing efficiency and may even cause traffic congestion and wasted time. Pre-diagnosing the alcohol sensor's condition could minimize these problems, but currently, alcohol sensors require fixed equipment and professional personnel for troubleshooting, which is inconvenient. Since the lifespan of an alcohol sensor is related to the number of uses and the duration of use, current technology sets a threshold for the number of uses or the duration of use. When the sensor exceeds this threshold, it issues a warning, reminding staff to repair it. However, this doesn't guarantee that the sensor will remain in good working order until then, making it impossible to promptly determine if a malfunction is present, assess its detection accuracy, and guarantee the accuracy of the test results. Summary of the Invention

[0003] The purpose of this invention is to provide an automatic detection method and device for alcohol sensor faults, so as to solve the problem that existing technologies cannot detect whether alcohol sensors are faulty in a timely manner.

[0004] This invention proposes an automatic detection method for alcohol sensor malfunctions, which includes the following steps:

[0005] 1) Test the alcohol sensor to obtain a test curve that reflects the alcohol content, including the peak value, the time to reach the peak value, the duration of the tail, the upward slope of the peak value, and the downward slope of the peak value.

[0006] 2) The alcohol sensor is judged to be faulty if any one of the following indicators is met: peak value of the curve, peak value arrival time of the curve, tail duration of the curve, upward slope of the peak value of the curve, and downward slope of the peak value of the curve.

[0007] The criteria for judging the peak value of the curve: whether the peak value of the curve satisfies the relationship between the peak value of the curve and the calibrated value, where the calibrated value is the alcohol content corresponding to the peak value of the curve of a fault-free alcohol sensor, and the relationship between the peak value of the curve and the calibrated value refers to the proportional relationship between the difference between different calibrated values ​​and the difference between the corresponding peak values ​​of the curve.

[0008] The criteria for judging the curve tailing time are: whether the curve tailing time obtained by the test is within the set curve tailing time. When the curve tailing time obtained by the test is greater than or equal to the set curve tailing time, the alcohol sensor is judged to be faulty.

[0009] The criteria for determining the peak arrival time of the curve: The peak arrival time of the curve refers to the time taken to reach the peak value at the start of the test. It is determined whether the peak arrival time of the curve obtained by the test is within the set time interval. If the peak arrival time of the curve obtained by the test is not within the set time interval, it is determined that the alcohol sensor is faulty.

[0010] The criteria for judging the rising slope of the curve peak: judge whether the rising slope of the curve peak obtained by the test is within the set rising slope range. When the rising slope of the curve peak obtained by the test is not within the set rising slope range, it is judged that the alcohol sensor is faulty. The rising slope of the curve peak refers to the ratio of the curve peak to the curve peak arrival time.

[0011] The criteria for judging the descent slope of the curve peak: It is determined whether the descent slope of the curve peak obtained by the test is within the set descent slope range. When the descent slope of the curve peak obtained by the test is not within the set descent slope range, it is determined that the alcohol sensor is faulty. The descent slope of the curve peak refers to the ratio between the curve peak and the time taken for the curve peak to drop to the set value.

[0012] The present invention also proposes an automatic detection device for alcohol sensor malfunctions, the device comprising a processor and a memory, wherein the processor executes a computer program stored in the memory to implement the above-described automatic detection method for alcohol sensor malfunctions.

[0013] The present invention proposes an automatic fault detection method and device for alcohol sensors. This method compares the peak value, peak arrival time, tail duration, peak rise slope, and peak fall slope of the alcohol sensor test results with corresponding set thresholds. If any of these fault conditions are met, the alcohol sensor is determined to be faulty. This invention can determine the presence of a fault in an alcohol sensor at any time based on its test curve and set thresholds, eliminating the need for professional personnel to perform testing with fixed equipment. This significantly improves fault detection efficiency and avoids erroneous test results when the fault is unknown, thus ensuring the accuracy of alcohol sensor detection.

[0014] Furthermore, in order to obtain the relationship between the curve peak value and the calibration value, the relationship between the curve peak value and the calibration value is as follows:

[0015] P3∈{[(P2-P1)(A3-A2) / (A2-A1)]+P2}*θ

[0016] In the formula, P1 and P2 are the peak values ​​of the curves tested by alcohol sensors without faults, A1 and A2 are the alcohol content values ​​corresponding to P1 and P2, A3 is the calibrated value of the test value, P3 is the peak value of the curve obtained by the test, and θ is the set peak value calculation threshold range. The set peak value calculation threshold range is obtained by testing using the factory test data and / or return-to-factory maintenance test data of alcohol sensors of the same type.

[0017] Furthermore, in order to accurately determine the set time interval, the time interval set in step 2) is obtained by testing using factory test data and / or return-to-factory maintenance test data of the same type of alcohol sensor.

[0018] Furthermore, in order to accurately determine the set tailing duration, the curve tailing duration set in step 2) is obtained by testing using factory test data and / or return-to-factory maintenance test data of the same type of alcohol sensor.

[0019] Furthermore, in order to accurately obtain the set rising slope threshold, the rising slope range set in step 2) is obtained by testing using factory test data and / or return-to-factory maintenance test data of the same type of alcohol sensor.

[0020] Furthermore, in order to accurately obtain the set descent slope threshold, the descent slope range set in step 2) is obtained by testing using factory test data and / or return-to-factory maintenance test data of the same type of alcohol sensor.

[0021] Furthermore, in order to enable timely repair or replacement of faulty alcohol sensors, the alcohol sensor is connected to an alarm device, which issues a repair alarm or replacement alarm when a fault is detected in the alcohol sensor.

[0022] Furthermore, to determine whether the alcohol sensor needs repair or replacement, this method can also detect it by setting a usage count threshold. When the alcohol sensor is found to be faulty and the number of times it has been used reaches the set usage count threshold, a replacement alarm is issued; when the alcohol sensor is found to be faulty and the number of times it has been used has not reached the set usage count threshold, a repair alarm is issued. Attached Figure Description

[0023] Figure 1 This is a flowchart of the automatic detection method for alcohol sensor faults of the present invention;

[0024] Figure 2 This is a voltage curve obtained from the alcohol sensor. Detailed Implementation

[0025] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0026] Method Implementation Examples

[0027] This invention provides an automatic detection method for alcohol sensor malfunctions, such as... Figure 1 As shown, the alcohol sensor is tested using a set test source to obtain a test curve reflecting the alcohol content. Any one of the following indicators of the test curve is judged: peak value, peak value arrival time, tail duration, peak value rise slope, and peak value fall slope. When any one of the indicators meets the corresponding fault judgment condition, it is determined whether the alcohol sensor is faulty. This method can detect whether the alcohol sensor is faulty at any time through the test source, which improves the fault detection efficiency and also ensures the accuracy of the detection results.

[0028] An alcohol sensor can convert a gas signal (alcohol content) into a voltage signal. This invention first tests the alcohol sensor to obtain a test curve reflecting the alcohol content. From the curve, we can determine the peak value, the arrival time of the peak value, the duration of the tail, the upward slope of the peak value, and the downward slope of the peak value. For example… Figure 2 The test curve shown has a peak value of 250 millivolts. The peak arrival time is 1000 milliseconds, and the tail duration is 9000 milliseconds, from the peak value until the signal is no longer output. The peak rise slope and peak fall slope can also be calculated. The peak rise slope is the ratio of the peak value to the peak arrival time, and the peak fall slope is the ratio of the peak value to the time it takes for the peak value to fall to the set value.

[0029] Then, the present invention makes a judgment based on at least one of the following indicators: curve peak value, curve peak value arrival time, curve tail duration, curve peak value rising slope, and curve peak value falling slope. If any of the indicators used meets the corresponding fault judgment condition, the alcohol sensor is judged to be faulty.

[0030] This invention, when diagnosing alcohol sensor faults, requires pre-calibrating judgment thresholds for different indicators using a large amount of measured data. This measured data consists of factory test data and / or return-to-factory repair test data for similar alcohol sensors. Before leaving the factory, the alcohol sensor undergoes factory testing to check if the sensor is functioning correctly. This factory test data includes test curves for alcohol sensors without faults and test curves for alcohol sensors with faults. Similarly, during the return-to-factory repair process, testing is also required to ensure successful repair. The return-to-factory repair test data also includes test curves for alcohol sensors without faults and test curves for alcohol sensors with faults. By statistically analyzing these test curves of both faulty and fault-free alcohol sensors, reasonable ranges for different indicators when the alcohol sensor is fault-free can be found. For example, when calibrating the peak arrival time of the curve as a judgment criterion, the peak arrival time of the curves corresponding to all alcohol sensor test curves without faults is statistically analyzed, and the peak arrival time of the curves corresponding to alcohol sensor test curves with faults is also statistically analyzed. Based on the large number of statistical values ​​obtained, a suitable range of peak arrival time for alcohol sensor test curves without faults is found. If it is found during the statistical process that when the peak arrival time of the curve is within 280 milliseconds-320 milliseconds, the corresponding alcohol sensor is not faulty, and when it exceeds 320 milliseconds or is less than 280 milliseconds, the corresponding alcohol sensor is faulty, then 280 milliseconds-320 milliseconds can be used as the judgment criterion for judging faults based on the peak arrival time of the curve.

[0031] The criteria for determining the peak value of the curve are: whether the peak value of the curve satisfies the relationship between the peak value of the curve and the calibration value, where the calibration value is the alcohol content corresponding to the peak value of the curve of a fault-free alcohol sensor, and the relationship between the peak value of the curve and the calibration value refers to the proportional relationship between the difference between different calibration values ​​and the difference between the corresponding peak values ​​of the curve.

[0032] The proportional relationship is as follows:

[0033] P3∈{[(P2-P1)(A3-A2) / (A2-A1)]+P2}*θ

[0034] In the formula, P1 and P2 are the peak values ​​of the curves obtained from testing a fault-free alcohol sensor, A1 and A2 are the alcohol content values ​​corresponding to P1 and P2, A3 is the calibrated value of the test value, P3 is the peak value of the curve obtained from the test, and θ is the set peak value calculation threshold range. The set peak value calculation threshold range is obtained through the threshold calibration method described above, with θ calibrated to [0.6, 1.1]. A1, A2, and A3 are all known alcohol content values, i.e., the alcohol content of the set test source. A fault-free alcohol sensor is tested using a test source with known alcohol content (A1, A2) to obtain the peak values ​​(P1, P2) of the curve. P1 and P2 can be obtained in real time when needed. This proportional relationship can be understood as a certain proportional relationship between alcohol content and the peak value of the output voltage. Based on the determined proportional relationship, the corresponding peak value range can be calculated when the tested alcohol content is known. When the peak value of the curve obtained from the actual test is not within the peak value range calculated by the above formula, the alcohol sensor is considered to be faulty. Based on the calibrated θ interval, the lowest peak value P of the curve corresponding to the known tested alcohol content can be calculated using the above formula when θ is 0.6. L When θ is 1.1, the highest peak value P of the curve corresponding to the known alcohol content can be calculated. H When P3 is not in [P L P H If the reading is within a certain range, the alcohol sensor is considered faulty.

[0035] The criteria for determining the curve tail duration are as follows: The test result is determined to be within the set curve tail duration. If the tested curve tail duration is greater than or equal to the set curve tail duration, the alcohol sensor is considered faulty. The voltage signal detected by the alcohol sensor, after reaching its peak, will gradually decrease over time until it reaches zero. Figure 2 As shown, the descent follows a pattern of rapid initial decrease followed by slower decrease. When the tailing duration of the curve exceeds the set duration, indicating severe tailing, it proves that the alcohol sensor is malfunctioning.

[0036] Among them, the judgment condition for the peak arrival time of the curve is: the peak arrival time of the curve refers to the time taken to reach the peak value at the start of the test. It is judged whether the peak arrival time of the curve obtained by the test is within the set time interval. When the peak arrival time of the curve obtained by the test is not within the set time interval, it is judged that the alcohol sensor is faulty.

[0037] The judgment condition for the rising slope of the curve peak is as follows: it is judged whether the rising slope of the curve peak obtained by the test is within the set rising slope range. When the rising slope of the curve peak obtained by the test is not within the set rising slope range, it is judged that the alcohol sensor is faulty. It can also be understood that within the above-mentioned set time interval, the test curve does not reach the curve peak or the curve peak reached does not meet the proportional relationship described in the judgment condition of the curve peak. It can also be understood that the time when the curve peak is reached is not within the range set by the above-mentioned curve peak arrival time.

[0038] The judgment condition for the descent slope of the curve peak is: whether the descent slope of the curve peak obtained by the test meets the set descent slope range. When the descent slope of the curve peak obtained by the test is not within the set descent slope range, it is judged that the alcohol sensor is faulty.

[0039] In another implementation, if only the peak arrival time and tail duration of the curve are used to determine equipment failure, it is not necessary to use a test source with known alcohol content for testing, nor is it necessary to calculate the peak value of the curve. The determination can be made directly by the peak arrival time and tail duration of the curve obtained from the test. These two indicators can be used for online real-time detection.

[0040] Meanwhile, to enable timely repair or replacement of faulty alcohol sensors, an alarm device is connected to the sensor. When a fault is detected, the alarm device will issue a repair or replacement alarm. To determine whether the alcohol sensor needs repair or replacement, this invention also uses a set usage threshold for alcohol sensor detection. When the alcohol sensor is determined to be faulty and the usage count has reached the set threshold, a replacement alarm is issued. For example, based on actual usage of the alcohol sensor, it has been found that when the usage count generally exceeds 50,000 times, the detected results are inconsistent with reality, indicating that the alcohol sensor has reached its service life. Therefore, a usage threshold of 50,000 times is set. If the above judgment condition indicates that the alcohol sensor is faulty and the usage count has exceeded 50,000 times, there is no need to continue repair; direct replacement is more time-saving and can avoid unnecessary expenses. When the alcohol sensor is determined to be faulty but the usage count has not reached the set usage threshold, it indicates that it still has usability, and a repair alarm is issued, indicating that repair is required.

[0041] The above methods can be used to determine whether the alcohol sensor is faulty based on different indicators, so that it can be replaced or repaired in a timely manner, improving the efficiency of fault detection and ensuring the accuracy of the test results.

[0042] Device Examples

[0043] The apparatus proposed in this embodiment includes a processor and a memory. The memory stores a computer program that can run on the processor. When the processor executes the computer program, it implements the method of the above-described method embodiment. That is, the method in the above embodiments should be understood as a process for automatically detecting alcohol sensor malfunctions that can be implemented by computer program instructions. These computer program instructions can be provided to the processor, causing the processor to execute these instructions to produce the functions specified in the above-described method flow.

[0044] In this embodiment, the processor refers to a processing device such as a microprocessor (MCU) or a programmable logic device (FPGA); the memory refers to a physical device used to store information, which typically involves digitizing the information and then storing it using electrical, magnetic, or optical methods. Examples include: various types of memory that store information electrically, such as RAM and ROM; various types of memory that store information magnetically, such as hard disks, floppy disks, magnetic tapes, magnetic core memory, bubble memory, and USB flash drives; and various types of memory that store information optically, such as CDs or DVDs. Of course, there are other types of memory, such as quantum memories and graphene memories.

[0045] The device, comprised of the aforementioned memory, processor, and computer program, is implemented by the processor executing corresponding program instructions within a computer. The processor can run various operating systems, such as Windows, Linux, Android, and iOS. As another implementation, the device may also include a display screen to show the detection curve results for reference by personnel.

Claims

1. An automatic detection method for alcohol sensor faults, characterized in that, The method includes the following steps: 1) Test the alcohol sensor to obtain a test curve that reflects the alcohol content, including the peak value, peak arrival time, tail duration, peak rise slope, and peak fall slope. 2) Judge at least one indicator. If any indicator meets the corresponding fault judgment condition, then the alcohol sensor is judged to be faulty. Criteria for determining the peak value of the curve: Whether the peak value of the curve meets the peak range determined by the relationship between the peak value and the calibration value, where the calibration value is the alcohol content corresponding to the peak value of the curve of a fault-free alcohol sensor, and the relationship between the peak value and the calibration value is as follows: In the formula, , The peak value of the curve is from a test of a fault-free alcohol sensor. , yes , The corresponding alcohol content value, The calibration value is for the test value. The peak value of the curve obtained from the test. To set the threshold range for peak value calculation; The criteria for judging the curve tailing duration: when the measured curve tailing duration is not within the set curve tailing duration, the alcohol sensor is judged to be faulty. Criteria for determining peak arrival time: Peak arrival time refers to the time taken to reach the peak value at the start of the test. If the peak arrival time of the curve obtained by the test is not within the set time interval, the alcohol sensor is judged to be faulty. The judgment condition for the rising slope of the curve peak: When the rising slope of the curve peak obtained by the test is not within the set rising slope range, it is judged that the alcohol sensor is faulty. The rising slope of the curve peak refers to the ratio of the curve peak to the curve peak arrival time. Judgment criteria for the slope of the curve peak: When the slope of the curve peak obtained by the test is not within the set slope range, it is determined that the alcohol sensor is faulty. The slope of the curve peak refers to the ratio between the curve peak and the time taken for the curve peak to drop to the set value.

2. The automatic detection method for alcohol sensor faults according to claim 1, characterized in that, The peak value calculation threshold range is set using factory test data and / or return-to-factory maintenance test data of similar alcohol sensors.

3. The automatic detection method for alcohol sensor faults according to claim 1 or 2, characterized in that, The time interval set in step 2) is obtained by testing using factory test data and / or return-to-factory maintenance test data of the same type of alcohol sensor.

4. The automatic detection method for alcohol sensor faults according to claim 1 or 2, characterized in that, The curve tailing duration set in step 2) is obtained by testing using factory test data and / or return-to-factory maintenance test data of the same type of alcohol sensor.

5. The automatic detection method for alcohol sensor faults according to claim 1 or 2, characterized in that, The rising slope range set in step 2) is obtained by testing using factory test data and / or return-to-factory maintenance test data of the same type of alcohol sensor.

6. The automatic detection method for alcohol sensor faults according to claim 1 or 2, characterized in that, The descent slope range set in step 2) is obtained from factory test data and / or return-to-factory maintenance test data of the same type of alcohol sensor.

7. The automatic detection method for alcohol sensor faults according to claim 1, characterized in that, The alcohol sensor is connected to an alarm device, which is used to issue a maintenance alarm or replacement alarm when a malfunction of the alcohol sensor is detected.

8. The automatic detection method for alcohol sensor faults according to claim 7, characterized in that, This method can also detect the problem by setting a usage threshold. When the alcohol sensor is found to be faulty and the number of times it has been used reaches the set usage threshold, a replacement alarm is issued. When the alcohol sensor is found to be faulty and the number of times it has been used has not reached the set usage threshold, a maintenance alarm is issued.

9. An automatic detection device for alcohol sensor malfunctions, characterized in that, The device includes a processor and a memory, the processor executing a computer program stored in the memory to implement the automatic detection method for alcohol sensor malfunctions as described in claim 1.

10. The automatic detection device for alcohol sensor faults according to claim 9, characterized in that, The peak value calculation threshold range is set using factory test data and / or return-to-factory maintenance test data of similar alcohol sensors.

11. The automatic detection device for alcohol sensor malfunction according to claim 9 or 10, characterized in that, The time interval set in step 2) is obtained by testing using factory test data and / or return-to-factory maintenance test data of the same type of alcohol sensor.

12. The automatic detection device for alcohol sensor malfunction according to claim 9 or 10, characterized in that, The curve tailing duration set in step 2) is obtained by testing using factory test data and / or return-to-factory maintenance test data of the same type of alcohol sensor.

13. The automatic detection device for alcohol sensor malfunction according to claim 9 or 10, characterized in that, The rising slope range set in step 2) is obtained by testing using factory test data and / or return-to-factory maintenance test data of the same type of alcohol sensor.

14. The automatic detection device for alcohol sensor malfunction according to claim 9 or 10, characterized in that, The descent slope range set in step 2) is obtained from factory test data and / or return-to-factory maintenance test data of the same type of alcohol sensor.

15. The automatic detection device for alcohol sensor faults according to claim 9, characterized in that, The alcohol sensor is connected to an alarm device, which is used to issue a maintenance alarm or replacement alarm when a malfunction of the alcohol sensor is detected.

16. The automatic detection device for alcohol sensor faults according to claim 15, characterized in that, This method can also detect the problem by setting a usage threshold. When the alcohol sensor is found to be faulty and the number of times it has been used reaches the set usage threshold, a replacement alarm is issued. When the alcohol sensor is found to be faulty and the number of times it has been used has not reached the set usage threshold, a maintenance alarm is issued.

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