JP2020091204A - Axle load measuring device, measuring accuracy diagnostic method, and measuring accuracy diagnostic program - Google Patents

Abstract

To make it possible, regardless of the presence or absence of travel of a road-specific vehicle, to determine whether measuring accuracy of axle load sensors arranged side by side in the direction of travel of the vehicle is appropriate.SOLUTION: An axle load sensor connection unit 12 receives input of measurement signals from a plurality of axle load sensors 2 to 4 that are arranged side by side in the direction of travel of a vehicle 100. A measured value DB 14 collects measured values according to the received measurement signals for each of the axle load sensors 2 to 4. A totalizing unit 23 totalizes the collected measured values for each of the axle sensors 2 to 4 to acquire a totalizing result. A determination unit 25, when the amount of difference in the totalizing results between two of the axle sensors 2 to 4 is within an appropriate range, determines that the measuring accuracy of the axle sensors is appropriate.SELECTED DRAWING: Figure 2

Description

The present invention relates to a technique for diagnosing whether or not the measurement accuracy of a shaft load sensor that measures the shaft load of a traveling vehicle is appropriate.

Conventionally, there has been a device for measuring the weight of a vehicle traveling on a road. This device processes the measurement signals of a plurality (two or more) of axle load sensors that are embedded in a road and arranged in the traveling direction of the vehicle to measure the weight of the traveling vehicle (see Patent Document 1, etc.). As is well known, the axle load sensor is a sensor used to measure a vertical force (axle weight) when a wheel attached to the axle passes by for each axle of the vehicle.

The axle load of the axle is calculated by processing measurement signals of a plurality of axle load sensors that are embedded side by side in the traveling direction of the vehicle. For example, for each axle, an average value of axle loads measured by a plurality of axle load sensors on the axle is calculated as the axle load of the axle. Further, the weight of the vehicle is the sum (total) of the axle loads calculated for each axle of the vehicle.

Further, Patent Document 1 describes a configuration for performing sensitivity correction (configuration for updating a correction coefficient) for each axle load sensor according to the measurement accuracy of the axle load without interrupting the measurement of the weight of the vehicle. ing. Specifically, for each axle load sensor, the weight of the vehicle calculated using the measurement data when a predetermined specific vehicle (vehicle whose vehicle data such as the number of axles and total weight is known) passes is true. The correction coefficient for correcting the sensitivity is updated so that the value becomes a value.

JP, 2010-261825, A

However, the specific vehicle in Patent Document 1 is
(1) It is a vehicle whose total weight (total value of axle weight of each axle) does not change depending on usage conditions.
(2) It is a vehicle in which there are no other vehicles with similar numbers of axles, distance between axles, axle weight, etc.
The vehicle must meet the conditions in.

Therefore, vehicles such as trucks and trailers for loading cargo do not satisfy the above condition (1). In addition, general passenger cars (private cars and company cars) do not satisfy the above condition (2). For this reason, the specific vehicle had to be a special vehicle rather than a general vehicle. In Patent Document 1, a self-propelled crane is used as a specific vehicle.

If the specific vehicle is a special vehicle, the period from the current traveling of the specific vehicle to the next traveling of the specific vehicle may be long. In the technique according to Patent Document 1, the period for determining the decrease in the measurement accuracy of the axle load sensor is the period from the current traveling of the specific vehicle to the next traveling of the specific vehicle. For this reason, in the technique according to Patent Document 1, there may occur a situation in which it is not possible to determine whether or not the measurement accuracy of the axle load sensor has decreased over a long period of time.

An object of the present invention is to provide a technique capable of determining whether or not the measurement accuracy of axle load sensors arranged side by side in the traveling direction of a vehicle is appropriate, regardless of whether or not a special vehicle is traveling.

The axial load measuring device of the present invention is configured as described below to achieve the above object.

A plurality of axle load sensors are arranged side by side in the traveling direction of the vehicle. The axle load sensor may be a single sensor that measures the axle weight of the vehicle, or a pair of sensors (a pair of wheel weight sensors) that measure the wheel weight for each wheel of the vehicle may be used in the vehicle width direction (vehicle They may be arranged in a direction orthogonal to the traveling direction).

A measurement signal of the shaft load sensor is input to the shaft load sensor connection portion. The measurement value collection unit collects a measurement value according to the input measurement signal for each axial load sensor. An aggregating unit obtains an aggregated result of aggregating the collected measurement values for each axle load sensor. The difference amount calculation unit calculates the difference amount of the aggregation result between the two axle load sensors. The determination unit determines whether or not the measurement accuracy of the axle load sensor is appropriate, depending on whether or not the difference amount is within the appropriate range.

Even if the plurality of axle load sensors arranged side by side in the traveling direction of the vehicle have the same measurement accuracy, the traveling vehicle is vibrating, so that the measurement values of the axle load do not always become the same. That is, even if the shaft load sensor has a proper measurement accuracy, the measured value of the shaft load may be a value close to the true value, a value relatively smaller than the true value, or a true value. It may be a relatively large value. However, statistically speaking, if the axle load sensors have proper measurement accuracy, if the axle load is measured for a certain number of axles (several thousands to tens of thousands), the true axle weights of these axles will be measured. And the average value of the measured values of the axle loads of these axles are close to each other.

From this, the totaling unit calculates the total value of the axle load measured for these axles as the aggregate result of the axle load measurement values measured for a certain number of axles for each axle load sensor. If you obtain the average value of the axle load measurement values for the axles, the root mean square of the axle load measurement values for these axles, etc., the aggregated results will be It becomes almost the same value. Therefore, it is possible to determine whether or not the measurement accuracy of these axle load sensors is appropriate, based on the amount of difference in the aggregation results between the axle load sensors. Therefore, regardless of whether or not the special vehicle is traveling, it can be determined whether or not the measurement accuracy of the axle load sensors arranged side by side in the traveling direction of the vehicle is appropriate.

Further, three or more axle load sensors are arranged side by side in the traveling direction of the vehicle, the difference amount calculation unit calculates the difference amount of the aggregation result for each combination of the two axle load sensors, and the determination unit determines that the difference amount is within the appropriate range. If there is a combination of the two axial load sensors that are not within the above range, it may be determined that there is the axial load sensor whose measurement accuracy is not appropriate.

Further, in this case, a combination of two axial load sensors whose difference amount is not within the proper range is extracted, and if one of the axial load sensors is common in all the extracted combinations, this common axis It may be determined that the measurement accuracy of the heavy sensor is not appropriate. That is, with this configuration, it is possible to specify the axial load sensor whose measurement accuracy is not appropriate.

Further, the totalizing unit may include a proper range setting unit that sets the proper range based on the totalized result of totaling the measured values for each axle load sensor. With this configuration, it is possible to determine the size (setting range) of the difference amount of the aggregation result used for determining whether the measurement accuracy of the axle load sensor is appropriate, according to the aggregation result. It is possible to improve the accuracy of determination as to whether the measurement accuracy of the sensor is appropriate.

According to the present invention, it is possible to determine whether or not the measurement accuracy of the axle load sensors arranged side by side in the traveling direction of the vehicle is appropriate regardless of whether or not the special vehicle is traveling.

It is a schematic diagram showing a vehicle weight measuring system to which an axle load measuring device concerning this example is applied. It is a block diagram which shows the structure of the principal part of the axial load measuring device concerning this example. 3A to 3C are views showing measurement data of the axle load sensor. It is a figure which shows calculated data. It is a flow chart which shows measurement processing of an axle load measuring device concerning this example. It is a flow chart which shows measurement accuracy diagnostic processing of an axle load measuring device concerning this example. It is a block diagram which shows the structure of the principal part of the axial load measuring device concerning another example.

Hereinafter, an axial load measuring device according to an embodiment of the present invention will be described.

<1. Application example>
FIG. 1 is a schematic diagram showing a vehicle weight measuring system to which an axle load measuring device according to this example is applied. The vehicle weight measuring system shown in FIG. 1 includes an axle load measuring device 1, three axle weight sensors 2 to 4, and two vehicle detection sensors 6 and 7. The axle load sensors 2 to 4 and the vehicle detection sensors 6 and 7 are connected to the axle load measuring device 1.

As shown in FIG. 1, the vehicle detection sensor 6, the axle load sensor 2, the axle load sensor 3, the axle load sensor 4, and the vehicle detection sensor 7 are arranged in this order in the traveling direction of the vehicle 100 (embedded) on the road. Has been done. The measurement section for measuring the axle load of the vehicle 100 is a section from the vehicle detection sensor 6 to the vehicle detection sensor 7. The vehicle detection sensor 6 detects the vehicle 100 entering the measurement section. The vehicle detection sensor 7 detects the vehicle 100 leaving the measurement section.

The axle load sensor 2 includes a pair of wheel load sensors 2R and 2L arranged side by side in the vehicle width direction of a vehicle 100 traveling on a road. Similarly, the axle load sensor 3 is formed by arranging a pair of wheel weight sensors 3R, 3L in the vehicle width direction of the vehicle 100 traveling on a road, and the axle load sensor 4 is a pair of wheel weight sensors 4R, 4L. Are arranged in the vehicle width direction of the vehicle 100 traveling on the road. The wheel load sensors 2R to 4R are embedded at positions where the wheels on the right side of the vehicle 100 pass. In addition, the wheel load sensors 2L to 4L are embedded at positions where wheels on the left side of the vehicle 100 pass. The wheel load sensors 2R to 4R and 2L to 4L are, for example, piezoelectric sensors, and output to the axle load measuring device 1 a measurement signal corresponding to the pressing force when the wheel passes. The vehicle detection sensors 6 and 7 are loop coil sensors, for example, and output a change in inductance to the axle load measuring device 1 as a vehicle detection signal (a signal indicating the presence or absence of the vehicle 100).

The vehicle detection sensors 6 and 7 may be optical sensors or radio wave sensors that are not buried in the road.

The wheel load sensors 2R to 4R output to the axle load measuring device 1 a measurement signal obtained by measuring the wheel load of the right wheel for each axle of the vehicle 100 traveling in the measurement section. Further, the wheel load sensors 2L to 4L output to the axle load measuring device 1 a measurement signal obtained by measuring the wheel load of the left wheel for each axle of the vehicle 100 traveling in the measurement section. That is, in the axle load measuring device 1, for each axle of the vehicle 100 traveling in the measurement section, the wheel weight of the right wheel is measured by the wheel load sensor 2R, the wheel load sensor 3R, and the wheel load sensor. The measurement signal from 4R is input. In addition, the axle load measuring device 1 includes a wheel load sensor 2L, a wheel load sensor 3L, a wheel load sensor 3L, and a wheel load sensor for the wheel load of the left wheel for each axle of the vehicle 100 traveling in the measurement section. The 4L measurement signal is input.

The distance L1 between the axial load sensor 2 and the axial load sensor 3 and the distance L2 between the axial load sensor 3 and the axial load sensor 4 in the traveling direction of the vehicle 100 have different lengths. The vehicle 100 that is running vibrates due to various factors such as road surface irregularities, speed, tire air pressure, etc., which complicately influence each other. If both the distance L1 between the adjacent axial load sensor 2 and the axial load sensor 3 and the distance L2 between the adjacent axial load sensor 3 and the axial load sensor 4 approximate to an integral multiple of the vibration wavelength of the vehicle 100, The weight measurement error may increase. Therefore, in this example, one of the distance L1 between the adjacent axial load sensors 2 and 3 or the distance L2 between the adjacent axial load sensors 3 and 4 is an integral multiple of the vibration wavelength of the vehicle 100. The distance L1 and the distance L2 are set to different lengths so that the other does not approximate an integral multiple of the vibration wavelength of the vehicle 100 even if the distance is approximated to.

The axle load measuring device 1 of this example cumulatively stores measurement values corresponding to the input measurement signal for each of the wheel load sensors 2R to 4R and 2L to 4L. In this example, this measurement value will be described as the wheel load calculated using the input measurement signal. However, this measurement value may be any value as long as it is a value corresponding to the input measurement signal. For example, this measurement value may be a digital value of the input measurement signal.

Since the moving vehicle 100 is vibrating, even if the measurement accuracy of the axle load sensors 2 to 4 is substantially the same, the measurement value of the axle load measured for the same axle is approximated by the axle load sensors 2 to 4. Not necessarily. That is, even if the axial load sensors 2 to 4 have proper measurement accuracy, the measured value of the axial load may be a value close to the true value or a value relatively smaller than the true value. , The value may be relatively larger than the true value. However, statistically, if the measurement accuracy of the axle load sensors 2 to 4 is appropriate, if the axle load is measured for a certain number of axles (thousands to tens of thousands), the axle weights of these axles will be measured. The average value of the true value of and the average value of the measured values of the axle loads of these axles are close to each other.

From this, for each of the axle load sensors 2 to 4, the total value (total) of the axle load measurement values measured for these axles is obtained as the aggregated result of the aggregate axle weight measurement values measured for a certain number of axles. If the average value of the axle load measurement values for these axles, the root mean square of the axle weights measured for these axles, etc. are obtained, the measurement accuracy is appropriate between the axle load sensors 2-4. The result is almost the same value. On the other hand, between the axial load sensors 2 to 4 having different measurement precisions, there is a certain difference in the above-mentioned aggregation result.

The axle load measuring device 1 of this example acquires the average value of the measured values of the axle loads that have been measured, as the above-mentioned aggregation result. The axle load measuring device 1 calculates the absolute value of the difference of the aggregation result (corresponding to the difference amount of the aggregation result in the present invention) for each combination of the two axle weight sensors 2 to 4. In this example, the axle load measuring device 1 is
(1) The absolute value of the difference between the aggregation results between the axle load sensor 2 and the axle load sensor 3 (hereinafter referred to as the first determination value X1) is calculated,
(2) The absolute value of the difference between the aggregation results between the axle load sensor 2 and the axle load sensor 4 (hereinafter referred to as the second determination value X2) is calculated,
(3) The absolute value of the difference between the aggregation results between the axle load sensor 3 and the axle load sensor 4 (hereinafter, referred to as the third determination value X3) is calculated.

In this example, since there are three axial load sensors 2 to 4, there are three combinations, but when there are four axial load sensors, there are six combinations, and If there are five, there are ten combinations. In addition, the first determination value, the second determination value, and the third determination value may be collectively referred to as a determination value.

If the first determination value X1 does not exceed the set threshold value Tth, the axle load measuring device 1 determines that the measurement accuracy of the axle load sensor 2 and the axle load sensor 3 is appropriate. If the first determination value X1 exceeds the set threshold value Tth, the axial load measuring device 1 determines that the measurement accuracy of at least one of the axial load sensor 2 and the axial load sensor 3 is not appropriate. Similarly, if the second determination value X2 does not exceed the set threshold value Tth, the axle load measuring device 1 determines that the measurement accuracy of the axle load sensor 2 and the axle load sensor 4 is appropriate. If the second determination value X2 exceeds the set threshold value Tth, the axle load measuring device 1 determines that the measurement accuracy of at least one of the axle load sensor 2 and the axle load sensor 4 is not appropriate. In addition, if the third determination value X3 does not exceed the set threshold value Tth, the axle load measuring device 1 determines that the measurement accuracy of the axle load sensor 3 and the axle load sensor 4 is appropriate. If the third determination value X3 exceeds the set threshold value Tth, the axle load measuring device 1 determines that the measurement accuracy of at least one of the axle load sensor 3 and the axle load sensor 4 is not appropriate.

For example, the axial load measuring device 1
(A) By comparing the first determination value X1 and the threshold value Tth, it is determined that the measurement accuracy of the shaft load sensor 2 and the shaft load sensor 3 is appropriate,
(B) By comparing the second determination value X2 with the threshold value Tth, it is determined that the measurement accuracy of at least one of the axle load sensor 2 and the axle load sensor 4 is not appropriate,
(C) If it is determined by comparing the third determination value X3 and the threshold value Tth that the measurement accuracy of at least one of the axle load sensor 3 and the axle load sensor 4 is not appropriate,
It is determined that the measurement accuracy of the shaft load sensor 2 and the shaft load sensor 3 is proper and the measurement accuracy of the shaft load sensor 4 is not proper.

As described above, in the axle load measuring device 1 according to this example, whether the axle load sensors 2 to 4 arranged side by side in the traveling direction of the vehicle 100 are appropriate in measurement accuracy regardless of whether or not a special vehicle is traveling. You can judge whether or not.

<2. Configuration example>
FIG. 2 is a block diagram showing the configuration of the main part of the axial load measuring device according to this example. The axle load measuring device 1 according to this example includes a control unit 11, an axle load sensor connection portion 12, a loop coil sensor connection portion 13, a measurement value database 14 (measurement value DB 14), and an output portion 15. ing.

The control unit 11 controls the operation of each part of the main body of the axial load measuring device 1 according to this example. The control unit 11 also includes a measurement value calculation unit 21, a measurement data generation unit 22, a totalization unit 23, a difference amount calculation unit 24, and a determination unit 25. Details of the measurement value calculation unit 21, the measurement data generation unit 22, the totalization unit 23, the difference amount calculation unit 24, and the determination unit 25 included in the control unit 11 will be described later.

The shaft weight sensor connection unit 12 receives the measurement signals of the connected shaft weight sensors 2 to 4. Specifically, the wheel load sensors 2R to 4R and 2L to 4L are connected to the axle load sensor connection portion 12, and the measurement signals of the wheel load sensors 2R to 4R and 2L to 4L are input. The axle load sensor connection unit 12 converts the input measurement signals of the wheel load sensors 2R to 4R and 2L to 4L into digital values and outputs them to the control unit 11.

Vehicle detection sensors 6 and 7 are connected to the loop coil sensor connection unit 13. The loop coil sensor connection unit 13 detects a change in inductance for each of the vehicle detection sensors 6 and 7 and outputs a vehicle detection signal indicating the presence or absence of the vehicle 100 to the control unit 11.

The measurement value DB 14 is a database that cumulatively stores the measurement data and the calculated data generated for the vehicle 100 that has traveled in the measurement section. The measurement data generation unit 22 described below generates measurement data and calculation data. The details of the measurement data and the calculation data will be described later. The measurement value DB 14 corresponds to the measurement value collecting unit according to the present invention.

The output unit 15 determines, for each of the axle load sensors 2, a determination result that determines whether or not the measurement accuracy is appropriate, measurement data of the vehicle 100 that has traveled in the measurement section, calculation data, and the like as required by a higher-level device (not shown). ) Is output.

Next, the measurement value calculation unit 21, the measurement data generation unit 22, the summation unit 23, the difference amount calculation unit 24, and the determination unit 25 included in the control unit 11 will be described.

The measurement value calculation unit 21 measures the measurement signal when the wheels of the vehicle 100 pass through the wheel load sensors 2R to 4R, 2L to 4L (actually, the wheel load sensors 2R to 4R and 2L to 4L). The wheel load is calculated using the digital value converted by the connection unit 12.

The measurement data generation unit 22 uses the vehicle detection signal input from the loop coil sensor connection unit 13 to divide the wheel weight calculated by the measurement value calculation unit 21 into units of the vehicle 100 traveling in the measurement section. The measurement data generation unit 22 generates measurement data for each of the axle load sensors 2-4. In this example, the measurement data generation unit 22 generates this measurement data for each vehicle.

FIG. 3 is a diagram showing measurement data of the axle load sensor. 3A is the measurement data of the axle load sensor 2, FIG. 3B is the measurement data of the axle load sensor 3, and FIG. 3C is the measurement data of the axle load sensor 4. The measurement data shown in FIGS. 3A to 3C are for the same vehicle 100. This measurement data is associated with a vehicle ID that identifies the vehicle 100 as shown in FIG. This vehicle ID is not for identifying the vehicle 100, but for each vehicle 100 traveling in the measurement section, the measurement data of the axle load sensor 2, the measurement data of the axle load sensor 3, and the measurement data of the axle load sensor 4. Is associated with.

In addition, here, the axle closest to the head of the vehicle 100 is the first axle, and the second axle and the third axle are arranged in order toward the tail of the vehicle. The wheel loads (right) of the axle load sensors 2 to 4 shown in FIG. 3 are calculated using the measurement signals of the corresponding wheel load sensors 2R to 4R (indicated by RA1, RB1, RC1, etc. in the figure). It is). The wheel loads (left) of the axle load sensors 2 to 4 shown in FIG. 3 are wheel loads calculated by using the measurement signals of the corresponding wheel load sensors 2L to 4L (indicated by LA1, LB1, LC1, etc. in the figure). It is). Further, the axle weights of the axle weight sensors 2 to 4 shown in FIG. 3 are obtained by using the axle weights calculated using the measurement signals of the corresponding axle weight sensors 2R to 4R and the corresponding axle weight sensors 2L to 4L. It is the sum of the wheel weight calculated by using.

The measurement data shown in FIG. 3 is an example of the vehicle 100 having three axles, and in the case of the vehicle 100 having two axles, data on the third axis is not included. Further, in the case of the vehicle 100 having four or more axles, data regarding the fourth axle, the fifth axle, etc. is also included depending on the number of axles.

Further, the measurement data generation unit 22 generates the calculation data shown in FIG. This calculation data is calculated based on the measurement results of the axle load sensors 2 to 4. Similar to the measurement data shown in FIG. 3, the calculated data is associated with the vehicle ID for identifying the vehicle 100. This vehicle ID is not for identifying the vehicle 100, but is associated with the measurement data shown in FIG. As shown in FIG. 4, the wheel weight (right), the wheel weight (left), and the axle weight are registered in this calculated data for each axle of the vehicle 100. The wheel load (right) of each axle is the average value of the wheel load of the wheel calculated using the measurement signals of the wheel load sensors 2R to 4R. The wheel load (left) of each axle is the average value of the wheel load of the wheel calculated using the measurement signals of the wheel load sensors 2L to 4L. The axle weight of each axle is the sum of the axle weight (right) and axle weight (left) of that axle. The vehicle weight, which is the weight of the vehicle 100, is the sum of the axle loads of the vehicle 100.

The measurement data generation unit 22 registers the measurement data of the axle load sensors 2 to 4 generated for each vehicle 100 and the calculation data calculated for the vehicle 100 in the measurement value DB 14.

The measurement data and the calculation data shown in FIG. 3 are also associated with the date and time when the vehicle 100 traveled in the measurement section.

The aggregation unit 23 aggregates the measurement data of the axle load sensors 2 to 4 registered in the measurement value DB 14 for the vehicle group (thousands to tens of thousands of vehicles 100) to be aggregated. Specifically, the totaling unit 23 calculates the average value of the axle loads in the vehicle groups to be aggregated for each of the axle load sensors 2 to 4.

The difference amount calculation unit 24 calculates the absolute value of the difference between the average values of the axial loads calculated by the totaling unit 23 for each combination of the two axial load sensors 2 to 4. Specifically, the difference amount calculation unit 24
(1) The absolute value (first determination value X1) of the difference between the average value of the axial load calculated for the axial load sensor 2 and the average value of the axial load calculated for the axial load sensor 3 is calculated,
(2) The absolute value (second determination value X2) of the difference between the average value of the axial load calculated for the axial load sensor 2 and the average value of the axial load calculated for the axial load sensor 4 is calculated,
(3) The absolute value (third determination value X3) of the difference between the average value of the axial load calculated for the axial load sensor 3 and the average value of the axial load calculated for the axial load sensor 4 is calculated.

The determination unit 25 uses the first determination value X1, the second determination value X2, and the third determination value X3 calculated by the difference amount calculation unit 24 so that the measurement accuracy of the axle load sensors 2 to 4 is appropriate. Is determined. Specifically, if the first determination value X1 does not exceed the set threshold value Tth, the determination unit 25 determines that the measurement accuracy of the axial load sensor 2 and the axial load sensor 3 is appropriate. If the first determination value X1 exceeds the set threshold value Tth, the determination unit 25 determines that the measurement accuracy of at least one of the axle load sensor 2 and the axle load sensor 3 is not appropriate. Similarly, if the second determination value X2 does not exceed the set threshold value Tth, the determination unit 25 determines that the measurement accuracy of the shaft load sensor 2 and the shaft load sensor 4 is appropriate. If the second determination value X2 exceeds the set threshold value Tth, the determination unit 25 determines that the measurement accuracy of at least one of the shaft load sensor 2 and the shaft load sensor 4 is not appropriate. If the third determination value X3 does not exceed the set threshold value Tth, the determination unit 25 determines that the measurement accuracy of the shaft load sensor 3 and the shaft load sensor 4 is appropriate. If the third determination value X3 exceeds the set threshold value Tth, the determination unit 25 determines that the measurement accuracy of at least one of the shaft load sensor 3 and the shaft load sensor 4 is not appropriate.

The threshold value Tth is stored in a memory (not shown) provided in the control unit 11.

The control unit 11 of the axle load measuring device 1 is composed of a hardware CPU, a memory, and other electronic circuits. When the hardware CPU executes the measurement accuracy diagnosis program according to the present invention, it operates as the measurement value calculation unit 21, the measurement data generation unit 22, the aggregation unit 23, the difference amount calculation unit 24, and the determination unit 25. The memory also has an area for developing the measurement accuracy diagnostic program according to the present invention and an area for temporarily storing data and the like generated when the measurement accuracy diagnostic program is executed. The control unit 11 may be an LSI in which a hardware CPU, a memory and the like are integrated. The hardware CPU is a computer that executes the measurement accuracy diagnosis method according to the present invention.

<3. Operation example>
The axle load measuring device 1 according to this example determines whether the axle 100 and the vehicle weight of the vehicle 100 that has traveled in the measurement section are measured accurately and whether or not the measurement accuracy of each of the axle load sensors 2 to 4 is appropriate. A measurement accuracy diagnosis process is performed.

FIG. 5 is a flowchart showing the measurement process of the axle load measuring device according to this example. The axle load measuring device 1 waits for the vehicle 100 to enter the measurement section (s1). The control unit 11 detects that the vehicle 100 has entered the measurement section based on the change in the inductance of the vehicle detection sensor 6 connected to the loop coil sensor connection unit 13.

When it is detected that the vehicle 100 has entered the measurement section, the measurement value calculation unit 21 stores a measurement signal for each of the wheel load sensors 2R to 4R and 2L to 4L connected to the axle load sensor connection unit 12. The data is cumulatively stored in (s2). That is, when it is detected that the vehicle 100 has entered the measurement section, the measurement value calculation unit 21 starts a process of cumulatively storing the measurement signal in the memory for each of the wheel load sensors 2R to 4R and 2L to 4L. To do. The time interval for storing the measurement signals of the wheel load sensors 2R to 4R and 2L to 4L is, for example, several tens msec to several 100 msec.

When it is detected that the vehicle 100 has exited from the measurement section (s3), the measurement value calculation unit 21 accumulates the measurement signal in the memory for each of the wheel load sensors 2R to 4R and 2L to 4L started at s2. The process of storing is completed (s4). The measurement value calculation unit 21 processes the measurement signals cumulatively stored in the memory for each of the wheel load sensors 2R to 4R and 2L to 4L to calculate the wheel load of each axle (s5).

The measurement signals of the wheel load sensors 2R to 4R and 2L to 4L change when the wheels of the vehicle 100 pass through. Therefore, the measurement value calculation unit 21 can obtain the number of axles of the vehicle 100 by counting the places where the measurement signals of the wheel load sensors 2R to 4R and 2L to 4L have changed. Further, the measurement value calculating unit 21 can calculate the wheel load by extracting the measurement signal when the wheel of each axle passes for each of the wheel load sensors 2R to 4R and 2L to 4L.

The measurement data generation unit 22 generates the measurement data shown in FIG. 3 for the vehicle 100 that has passed the measurement section this time (s6). This measurement data can be generated based on the wheel load of each axle calculated by the measurement value calculation unit 21 for each of the wheel load sensors 2R to 4R and 2L to 4L. Further, the measurement data generation unit 22 generates the calculation data shown in FIG. 4 (s7). This calculation data can be generated based on the measurement data generated in s6. That is, this calculation data can also be generated based on the wheel load of each axle calculated by the measurement value calculation unit 21 for each of the wheel load sensors 2R to 4R and 2L to 4L.

The measurement data generation unit 22 stores the measurement data generated in s6 and the calculation data generated in s7 in the measurement value DB 14 (s8), and returns to s1.

In this way, the axle load measuring device 1 cumulatively stores the measurement data shown in FIG. 3 in the measurement value DB 14 for each vehicle 100 that has passed through the measurement section. Further, the axle load measuring device 1 detects whether or not the vehicle 100 is overloaded, the vehicle 100 is in a partially loaded state in which the load is biased to the left or right, or the like, based on the calculation data generated in s7. Can also be done. Further, the calculation data stored cumulatively in the measurement value DB 14 can be used as useful information for determining the necessity of road repair work or the like.

Next, the measurement accuracy diagnosis process will be described. FIG. 6 is a flowchart showing the measurement accuracy diagnosis process of the axle load measuring device according to this example. This measurement accuracy diagnosis process is a process executed at an appropriate timing. For example, it may be 0:00 am every Monday, 0:00 am on the first day of every month, or 0:00 am on the first day of even or odd months, or at a timing designated by the administrator. Good.

The control unit 11 determines the target vehicle group (s11). The number of vehicles 100 belonging to this target vehicle group is several thousand to tens of thousands. For example, a vehicle 100 that has passed the measurement section in the last week, a vehicle 100 that has passed the measurement section in the last month, or the like may be set as the vehicle 100 belonging to the target vehicle group, or finally the measurement section. The vehicle 100 that has passed through may be the first vehicle, and a predetermined number of vehicles (thousands to tens of thousands) that are continuous with this vehicle 100 may be used. The vehicles 100 belonging to the target vehicle group may be limited by the number of axles. For example, the vehicle 100 belonging to the target vehicle group may be provided with conditions such as the vehicle 100 having two axles or the vehicle 100 having three or less axles.

The aggregation unit 23 reads out the measurement data stored in the measurement value DB 14 for each vehicle 100 belonging to the target vehicle group determined in s11, and measures the axle load sensors 2 to 4 for the vehicle 100 belonging to the target vehicle group. The average value of the axle weights thus calculated is calculated as the totalization result (s12). Since the number of vehicles 100 belonging to the target vehicle group determined in s11 is several thousand to tens of thousands, statistically, between the axle load sensors 2 to 4 having substantially the same measurement accuracy, the counting result is obtained. The average value of the axial load calculated as is approximately the same. On the other hand, between the axial load sensors 2 to 4 whose measurement accuracy is not substantially the same, there is some difference in the average value of the axial loads calculated as the aggregation result.

The difference amount calculation unit 24 calculates, for each combination of the two axle load sensors 2 to 4, the absolute value of the difference between the average values of the axle loads calculated by the aggregation unit 23 as a determination value (s13). Specifically, the difference amount calculation unit 24
(1) The absolute value (first determination value X1) of the difference between the average value of the axial load calculated for the axial load sensor 2 and the average value of the axial load calculated for the axial load sensor 3 is calculated,
(2) The absolute value (second determination value X2) of the difference between the average value of the axial load calculated for the axial load sensor 2 and the average value of the axial load calculated for the axial load sensor 4 is calculated,
(3) The absolute value (third determination value X3) of the difference between the average value of the axial load calculated for the axial load sensor 3 and the average value of the axial load calculated for the axial load sensor 4 is calculated.

The determination unit 25 uses the first determination value X1, the second determination value X2, and the third determination value X3 calculated by the difference amount calculation unit 24 to measure the measurement accuracy for each of the axle load sensors 2 to 4. Is determined to be appropriate. Specifically, the determination unit 25 determines whether or not there is a determination value (first determination value X1, second determination value X2, and third determination value X3) that exceeds the set threshold value Tth. (S14). If there is no judgment value that exceeds the set threshold value Tth, that is, if the first judgment value X1, the second judgment value X2, and the third judgment value X3 are all less than or equal to the threshold value Tth. , It is determined that the measurement accuracy of all the axial load sensors 2 to 4 is appropriate (s15).

If there is a determination value that exceeds the threshold Tth, the determination unit 25 determines whether there is a determination value that does not exceed the threshold Tth (s16). At s16, it is determined whether all the determination values (the first determination value X1, the second determination value X2, and the third determination value X3) calculated at s13 exceed the threshold value Tth. When all of the determination values calculated in 13 exceed the threshold value Tth, the determination unit 25 determines that there is the axle load sensors 2 to 4 with improper measurement accuracy (s20). In s20, the determination unit 25 does not specify the axle load sensors 2 to 4 whose measurement accuracy is not appropriate.

Further, when it is determined in s16 that there is a determination value that does not exceed the threshold Tth, the determination unit 25 determines whether there are multiple determination values that exceed the threshold Tth (s17). In other words, in s17, it is determined whether or not there is one determination value that does not exceed the threshold value. If there is one determination value that does not exceed the threshold value, the determination unit 25 determines in s20 that there are axle load sensors 2 to 4 whose measurement accuracy is not appropriate.

When the determination unit 25 determines in s17 that there are a plurality of determination values that exceed the threshold value Tth, the determination unit 25 is common to all the combinations of the axle load sensors 2 to 4 that depend on the plurality of determination values that exceed the threshold value Tth. It is determined whether the axial load sensors 2 to 4 are included (s18). In this example, since there are three axle load sensors 2 to 4, when there are two determination values that exceed the threshold value, the combination of the axle load sensors 2 to 4 that depends on the determination value that exceeds this threshold value is All of them include the common axial load sensors 2 to 4. Therefore, in this example, it is not necessary to provide the process related to s18. On the other hand, when the number of axial load sensors is four or more, the axial load sensor that is common to all the combinations of the axial load sensors 2 to 4 that depend on the determination values among the plurality of determination values that exceed the threshold value Tth. 2 to 4 may not be included. That is, the process of s18 is a process required when using four or more axial load sensors 2-4.

In s18, the determination unit 25 includes, in a plurality of determination values that exceed the threshold value Tth, all of the combinations of the axial load sensors 2 to 4 related to the determination values, the shared axial load sensors 2 to 4 are included. If it is determined that the measurement accuracy of the common axle load sensors 2 to 4 is not appropriate (s19).

Note that the determination unit 25 includes, in a plurality of determination values that exceed the threshold value Tth in s18, the axle load sensors 2 to 4 that are common to all the combinations of the axle load sensors 2 to 4 related to the determination values. If not, it is determined in s20 that there are axle load sensors 2 to 4 whose measurement accuracy is not appropriate.

The control unit 11 outputs the determination result by the determination unit 25 (the determination result at s15, s19, or s20) from the output unit 15 to the higher-level device (s21), and ends this processing.

As described above, in the axle load measuring device 1 according to this example, whether the axle load sensors 2 to 4 arranged side by side in the traveling direction of the vehicle 100 are appropriate in measurement accuracy regardless of whether or not a special vehicle is traveling. You can judge whether or not.

In the above example, the average value of the axle loads measured for the vehicles 100 belonging to the target vehicle group is calculated as the aggregation result for each axle load sensor 2-4, but for each axle load sensor 2R-4R, 2L-4L. Alternatively, the average value of wheel weights measured for the vehicles 100 belonging to the target vehicle group may be calculated as the aggregation result. In this case, if the above-described measurement accuracy diagnosis process is executed using the aggregated results of the wheel load sensors 2R to 4R, it can be determined whether the measurement accuracy of the wheel load sensors 2R to 4R is appropriate. In addition, if the above-described measurement accuracy diagnosis process is executed using the aggregation results of the wheel load sensors 2L to 4L, it can be determined whether or not the measurement accuracy of the wheel load sensors 2L to 4L is appropriate.

Further, in the above example, the axial load sensors 2 to 4 are composed of the pair of wheel load sensors 2R to 4R and 2L to 4L, but they may be an integrated type which is not divided into left and right. Good.

In addition to the wheel load of each wheel of the vehicle 100, the axle load of each axle of the vehicle 100, and the weight of the vehicle 100 described above, the axle load measuring device 1 measures the speed of the vehicle 100 and the distance between the axles of the vehicle 100. The distance and the like may be measured and additionally registered in the calculation data shown in FIG.

<4. Modification>
FIG. 7 is a block diagram showing a configuration of a main part of an axial load measuring device according to another example. The axial load measurement value 1A according to this example differs from the above example in that the threshold value setting unit 26 is provided. In the above example, the threshold value Tth to be compared with the determination values (the first determination value X1, the second determination value X2, and the third determination value X3) is set in advance, but in this example, the totalization is performed. The threshold value setting unit 26 sets the threshold value Tth in accordance with the counting result acquired by the unit 23 for each of the axle load sensors 2 to 4. The tabulation result is, for example, an average value of axle loads measured for the vehicles 100 belonging to the target vehicle group.

In this example, the threshold setting unit 26 sets the minimum value of the aggregation result acquired for each of the axle load sensors 2 to 4, the maximum value of the aggregation result acquired for each of the axle weight sensors 2 to 4, or each of the axle load sensors 2 to 4. Use any of the average values, etc., of the aggregated results obtained in 1. The value used as the reference value by the threshold value setting unit 26 may be determined in advance. The threshold setting unit 26 sets the threshold Tth based on the reference value. For example, the threshold setting unit 26 sets, for example, a predetermined ratio (for example, 3%, 5%, 10%) of the reference value to the threshold Tth.

In this way, the threshold value setting unit 26 sets the threshold value Tth according to the measured value of the axial load in the axial load sensors 2 to 4, so that it is possible to improve the determination accuracy of whether the measurement accuracy is appropriate.

The threshold setting unit 26 may execute the process of setting the threshold Tth between s12 and s14 shown in FIG. That is, the threshold setting unit 26 may execute the process of setting the threshold Tth before the process of s13 shown in FIG. 6 or after the process of s13.

In the above example, the average value of the axle loads measured for the vehicles 100 belonging to the target vehicle group is acquired as the aggregate result for each of the axle load sensors 2 to 4, but the aggregate result belongs to the target vehicle group. The sum of the axle loads measured for the vehicle 100 may be used, or the root mean square of the axle loads measured for the vehicles 100 belonging to the target vehicle group may be used.

Further, in the above example, the example in which the three axial load sensors 2 to 4 are arranged in the traveling direction of the vehicle 100 has been described, but the number of axial load sensors arranged in the traveling direction of the vehicle 100 is two or more. Any number can be used as long as it is.

The present invention is not limited to the above embodiments as they are, and can be embodied by modifying the constituent elements within a range not departing from the gist of the invention in an implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, the constituent elements of different embodiments may be combined appropriately.

Furthermore, the correspondence relationship between the configuration according to the present invention and the configuration according to the above-described embodiment can be described as the following supplementary notes.
<Additional Notes> An axle load sensor connection portion (12) to which measurement signals of a plurality of axle load sensors (2 to 4) arranged side by side in the traveling direction of the vehicle (100) are input,
A measurement value collection unit (14) that collects measurement values corresponding to the input measurement signals for each of the axle load sensors (2 to 4);
An aggregating unit (23) that aggregates the collected measurement values for each of the axle load sensors (2 to 4) and obtains an aggregated result;
A difference amount calculation unit (24) for calculating a difference amount of the aggregation result between the two axle load sensors (2 to 4);
A shaft load measuring device (1), comprising: a determination unit (25) that determines whether or not the measurement accuracy of the shaft load sensor is appropriate depending on whether the difference amount is within a proper range.

1, 1A... Axle load measurement value 2... Axle load sensor 2-4... Axle load sensor 2R-4R, 2L-4L... Wheel load sensor 2R... Wheel load sensor 6, 7... Vehicle detection sensor 11... Control unit 12... Axis Heavy sensor connection 13... Loop coil sensor connection 14... Measurement value database (measurement value DB)
15... Output unit 21... Measurement value calculation unit 22... Measurement data generation unit 23... Aggregation unit 24... Difference amount calculation unit 25... Judgment unit 26... Threshold setting unit 100... Vehicle

Claims (9)

An axle load sensor connection portion into which measurement signals of a plurality of axle load sensors arranged side by side in the traveling direction of the vehicle are input,
For each of the axle load sensors, a measurement value collection unit that collects measurement values according to the input measurement signal,
For each of the axle load sensors, an aggregate unit that aggregates the collected measurement values and acquires the aggregate result,
A difference amount calculation unit that calculates a difference amount of the aggregation result between the two axle load sensors,
An axle load measuring device, comprising: a determination unit that determines whether or not the measurement accuracy of the axle load sensor is appropriate depending on whether the difference amount is within an appropriate range. The axial load sensors are arranged side by side in the traveling direction of the vehicle by three or more,
The difference amount calculation unit calculates the difference amount of the aggregation result for each combination of the two axle load sensors,
The axle load measuring device according to claim 1, wherein the determining unit determines that there is the axle load sensor having an incorrect measurement accuracy if there is a combination of the two axle load sensors in which the difference amount is not within an appropriate range. .. The determination unit extracts a combination of the two axial load sensors whose difference amount is not within the appropriate range, and if one of the axial load sensors is common in all the extracted combinations, this common The axial load measuring device according to claim 2, which determines that the measurement accuracy of the axial load sensor that is present is not appropriate. The axial load measurement according to any one of claims 1 to 3, further comprising: an appropriate range setting unit that sets the appropriate range based on the aggregated result obtained by the aggregation unit totalizing the measurement values for each of the axial load sensors. apparatus. The axle load measuring device according to claim 1, wherein the aggregating unit acquires, for each of the axle load sensors, an average value of measurement values collected as the aggregation result. The axle load measuring device according to claim 1, wherein the axle load sensor is a pair of wheel weight sensors arranged in a vehicle width direction. The axle load measuring device according to claim 1, further comprising a vehicle weight calculator that calculates the weight of the vehicle by using the measurement signals of the plurality of axle load sensors when the vehicle is traveling. For each of a plurality of axle load sensors arranged side by side in the traveling direction of the vehicle, a measurement value collecting step of collecting measurement values according to the measurement signal input from the axle load sensor,
For each of the axle load sensors, aggregating the collected measurement values, and aggregating step of obtaining an aggregate result,
A difference amount calculating step of calculating a difference amount of the aggregation result between the two axle load sensors,
A determination step of determining whether or not the measurement accuracy of the axle load sensor is appropriate depending on whether or not the difference amount is within an appropriate range. For each of a plurality of axle load sensors arranged side by side in the traveling direction of the vehicle, a measurement value collecting step of collecting measurement values according to the measurement signal input from the axle load sensor,
For each of the axle load sensors, aggregating the collected measurement values, and aggregating step of obtaining an aggregate result,
A difference amount calculating step of calculating a difference amount of the aggregation result between the two axle load sensors,
A determination accuracy determining program that causes a computer to execute a determination step of determining whether or not the measurement accuracy of the axle load sensor is appropriate depending on whether the difference amount is within an appropriate range.

Images