JPH11148852A - Measuring method and device for vehicle weight - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately measure a seated load vehicle weight by placing a plurality of load sensors in turn in the running direction and obtaining correction load from load data detected with each load sensor when the vehicle passes over using a specific equation. SOLUTION: On a vehicle running path, a plurality of load sensors are arranged in turn in the direction of the vehicle. Among these plurality of load sensors, a load sensor for determining load and an origin position corresponding sensor are arbitrarily set and a polynomial approximation is performed with the load data detected with each load sensor. Then a correction load ys is obtained by using an equation and (i)th frequency of (n) frequencies obtained with frequency analysis of the approximation polynomial which is to define the origin as the phase origin, its amplitude Ai, the phase ±i and the distance (x) from the origin to the load sensor and the vehicle speed (v). Using this correction load ys and load L detected with the load sensor, the vehicle weight W is obtained with W=L-ys.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a weight measuring method and a vehicle weight measuring device capable of measuring the weight of a running vehicle with high accuracy.

[0002]

2. Description of the Related Art There is a weight measuring device for measuring the weight of a running vehicle. FIG. 8 shows an example of this. Load cell bending plates (hereinafter referred to as load cells) 1a and 1b that output detection signals corresponding to loads are laid on the road surface of the road 3 as load detection sensors. The measurement values are obtained based on the detection signals of the load cells 1a and 1b that have received the tire pressure of the vehicle 4 traveling on the vehicle.

However, in the case of such a conventional device, the vehicle weight can be measured with high accuracy when the vehicle 4 is stationary or running at a very low speed. Since the vehicle body vibrates due to the unevenness and the vibration of the vehicle itself, the load on the tire that is in contact with the road surface fluctuates, and when the vehicle passes over the load detection sensor, the load received by the load detection sensor is stationary. In some cases, there is a difference in comparison with the load caused by the vehicle weight, so that an error has occurred in the measured value of the vehicle weight.

[0004]

As described above, the conventional vehicle weight measuring device lays the load cell as a load detection sensor on the road surface and outputs a detection signal of the load cell that receives the tire pressure of the vehicle running on the road. Originally, it is a structure that obtains measured values, so when the running speed of the vehicle is fast, the tire tread pressure fluctuates due to the vibration of the vehicle body due to the unevenness of the road surface, so that accurate weight measurement can be performed. There was a difficult problem.

[0005] Overloading of cargo trucks and trailers
Vehicle weight measuring devices are indispensable for monitoring and controlling the pavement of the road surface, as it is the cause of the accident and damages the pavement of the road surface.However, the development of technology that can accurately measure the weight of a running vehicle has been developed. It is urgent. Therefore, an object of the present invention is to provide a weight measuring device and a vehicle weight measuring method capable of measuring a vehicle weight during traveling with high accuracy.

[0006]

In order to achieve the above object, the present invention is configured as follows. That is, in a vehicle weight measurement device that measures the weight of a vehicle using a load sensor, a plurality of load sensors arranged in the vehicle traveling direction in the traveling direction of the vehicle, and a load for determining a load among the plurality of load sensors. The load determination sensor and the sensor corresponding to the origin position are arbitrarily set, a polynomial approximation is performed from the load data detected by each load sensor, and the frequency analysis of the approximate polynomial in which the origin is the phase origin is performed.
From the i-th frequency fi of these frequencies, its amplitude Ai, phase φi, the distance x from the origin to the load determination sensor, and the vehicle speed v, , A correction load ys is obtained, and the obtained correction load ys and
And calculating means for obtaining the vehicle weight W at W = L-ys from the load L detected by the load determination sensor.

In the system of the present invention having such a configuration, a plurality of load sensors are sequentially installed in the traveling direction of the vehicle, and among the plurality of load sensors, a load determination sensor is arbitrarily set, and a sensor for determining the origin position is provided. Is arbitrarily set, and the calculating means performs a polynomial approximation from the load data detected by each load sensor when passing through the vehicle, and performs frequency analysis of an approximate polynomial in which the origin is set to the phase origin. From the i-th frequency fi of the frequency, its amplitude Ai, phase φi, the distance x from the origin to the load determination sensor, and the vehicle speed v, Calculate the correction load ys. Then, the vehicle weight W is obtained from the obtained corrected load ys and the load L detected by the load determination sensor by W = L-ys.

In the present invention, the vehicle weight and the transit time obtained by a plurality of load sensors, for example, piezo sensors, which are sequentially installed in the traveling direction of the vehicle on the road surface, are taken as quantization data of the vehicle vibration, and the vibration frequency is used by using this data. Analyze and re-synthesize the vehicle vibration waveform, and use the obtained re-synthesized waveform of the vehicle vibration to estimate the vehicle vibration state at the time of passing a load sensor at a known distance, for example, a load determination sensor using a load cell or the like. , The deviation from the vibration center value is obtained, and the deviation is corrected with respect to the vehicle weight measurement value obtained by the load determination sensor (load cell, etc.), thereby removing the vehicle vibration component during running and stopping the vehicle. Closer to the vehicle weight at

Therefore, according to the present invention, the true axle load can be accurately measured by correcting the axle load of a running vehicle which vibrates due to the influence of road surface unevenness or the like. A vehicle weight measuring method and a vehicle weight measuring device can be provided.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIGS. 1 and 2 show a configuration example of the present apparatus. FIG. 1 shows an example of the arrangement of sensors on a road surface.
a and 1b are load cell bending plates (hereinafter referred to as load cells) as load sensors, and 2a and 1b.
Reference numerals 2b, 2c,... Denote piezo sensors as load sensors. Each of the piezo sensors 2a, 2b, 2c,... Is a sensor using a piezoelectric element, and when receiving a pressure, outputs an electric signal instantaneously corresponding to the received pressure.

These piezo sensors 2a, 2b, 2c,
Are elongated shapes, are arranged at regular intervals in the vehicle traveling direction on the road, and are laid along the longitudinal direction in the transverse direction of the road 3.

The load cells 1a and 1b are sensors capable of obtaining an electric signal corresponding to the received load. In this case, the load cells 1a and 1b are of a rectangular shape, and can detect both left and right wheels of the tire of the traveling vehicle 4 separately. They are arranged side by side on the road 3. The vehicle 4 traveling in one direction on the road
Are sequentially stepped on the piezo sensors 2a, 2b, 2c,... First, and are sequentially arranged so that they pass through the load cells 1a, 1b.

FIG. 2 is a block diagram showing the system configuration of the present apparatus. In the figure, I / F 21 is an interface,
It is an interface for taking in the detection outputs of the piezo sensors 2a, 2b, 2c,... And the detection outputs of the load cells 1a, 1b. Reference numeral 22 denotes an A / D converter, and I / F 2
Piezo sensors 2a, 2b, 2 taken in through
, and the detection outputs of the load cells 1a and 1b are sampled and converted into digital signals.

Reference numeral 23 denotes an arithmetic processing unit. The arithmetic processing unit 23 is a piezo sensor 2 obtained by the A / D converter 22.
a, 2b, 2c,... are converted into continuous data by a plurality of polynomial approximations. From the obtained continuous data, frequency components (A: amplitude, f:
(Frequency, φ: phase), and using the obtained frequency component, re-synthesizing processing of the dynamic axle double waveform by the following equation (1).

[0015] (I, n = 1, 2, 3,...) Where fi is the i-th frequency of n frequencies obtained by frequency analysis of an approximate polynomial in which the origin is the phase origin, and Ai is f
i is the amplitude and phase φi is the phase of fi; x is the distance from the origin position (in this example, the first piezo sensor arrangement position in the piezo sensor arrangement area) to the load determination sensor (in this example, the load cell); Is the vehicle speed.

In this case, the load determining sensors are load cells 1a and 1b, and the origin of the distance x is the load cells 1a, 2b, 2c,.
This is the piezo sensor 2a farthest from 1b.

Further, the arithmetic processing unit 23 uses the axle load sample value (detected load L) by the load cells 1a and 1b and the deviation (correction load ys) of the load cell position from the vehicle dynamic axle load vibration center value. (2) has a function of obtaining the stationary axle weight W of the vehicle as the vehicle weight.

W = L-ys (2) Reference numeral 24 denotes an output unit for displaying or printing the obtained static axle weight.

The operation of the apparatus having such a configuration will be specifically described with reference to the processing flow shown in FIG. It is assumed that the vehicle 4 travels and passes through the area of the sensor 3 on the road surface of the road 3. At this time, the vehicle 4 sequentially steps on the piezo sensors 2a, 2b, 2c,... Laid on the road surface, and finally steps on the load cells 1a, 1b.

At this time, each of the piezo sensors 2
a, 2b, 2c,... and the load cells 1a, 1b,
A signal corresponding to each received tread pressure is obtained. These signals are input to the A / D converter 22 via the I / F 21, where they are converted into digital signals (quantized data). This is the vehicle axle load sampling by the plurality of piezo sensors (step S1 in FIG. 3), whereby the quantized data as indicated by the symbol L in FIG. 4 is obtained.

In this manner, the changing axle load of the passing vehicle 4 due to the influence of the unevenness of the road surface is determined by the piezo sensor 2.
a, 2b, 2c,... are each extracted as an instantaneous value at the time of passing, and are converted into digital data by the A / D converter 23 to be quantized data. Piezo sensors 2a, 2b,
.. And the quantized data L obtained from the detected outputs of the load cells 1a and 1b are stored in a memory (not shown), and the piezo sensors 2a, 2b and 2
When the quantized data of c,... and the load cells 1a, 1b are completed, the arithmetic processing unit 23 starts processing.

That is, the piezo sensors 2a, 2b, 2
The instantaneous values of the quantized data of c,.
Is processed as follows. In the arithmetic processing unit 23,
First, the input is converted into continuous data of quantized data by a plurality of polynomial approximations (step S2).

As a result, the obtained continuous data is denoted by D1 shown in FIG. In this way, the quantized data (outputs of the piezo sensors 2a, 2b, 2c,...) Are converted into continuous data D1 as shown in FIG.
Convert to

Next, the arithmetic processing unit 23 outputs the continuous data D1
For the frequency components f1, f2, f
.. Are extracted (step S3). Frequency components (A: amplitude, f: frequency, φ: phase) extracted from the obtained continuous data D1 by the frequency analysis method are, for example, as shown in FIG.
It is as shown in FIG.

Next, the arithmetic processing unit 23 performs a re-synthesis process of the dynamic shaft weight waveform Wrs (step S4). That is, the arithmetic processing unit 23 obtains the obtained frequency components f1, f2, f3,.
And the processing of equation (1) (ys = ΣAi sin ｛2πfi ×
By executing (x / v) + φi｝), the dynamic axle load waveform Wrs is re-synthesized.

The portion indicated by the dotted line denoted by reference numeral Wrs in FIG. 4 is the re-combined dynamic axle load waveform Wrs. This dynamic axle load waveform W
Next, the arithmetic processing unit 23 obtains the deviation ys from rs, and performs a process of obtaining the stationary axle weight W of the vehicle from this (step S
5).

That is, the arithmetic processing unit 23 performs a process of calculating the stationary axle weight W of the vehicle, which is performed by the axle load sample value L and the load cell 1 by the load cells 1a and 1b.
Deviation y from the center value of the vehicle dynamic axle vibration at a and 1b
Using s, it is obtained by the calculation of the above equation (2).

The obtained stationary axle weight W is output from the output unit 2.
5 and displayed or printed, or stored in a storage means. FIG. 6 conceptually shows the flow of processing in the arithmetic processing unit 24 described above. That is, a detection signal corresponding to the tread pressure due to the tire tread pressure of the vehicle is obtained from the plurality of sensors 2a, 2b, 2c,..., 1a, 1b, sampled and quantized (FIG. 6 (a)). Based on the obtained data, continuous data is obtained by interpolation using polynomial approximation (FIG. 6B).

Next, the continuous data is converted into a predetermined time unit Δt.
And frequency analysis is performed to obtain a frequency component (FIG. 6C). Then, the dynamic axle load waveform Wrs is recombined to predict the waveform at the position P of the load cells 1a and 1b, and a deviation ys between this predicted value and the waveform vibration center position (center value) is estimated (FIG. 6 (d)).

By correcting the deviation ys with respect to the axle load sampling value L at the position of the load cells 1a and 1b of the vehicle, a value corresponding to the stationary axle weight W of the vehicle 4 can be obtained.

As described above, the axle load of the running vehicle is detected by the piezo sensor for detecting the tire tread pressure of the vehicle which is arranged at regular intervals in the traveling direction of the vehicle on the road surface of the vehicle and the load cell provided at the final stage position. The state of fluctuation of the axle load and axle vibration of the traveling vehicle is detected by detection outputs of a plurality of piezo sensors arranged in order in the traveling direction of the vehicle, and the variation tendency and the average value (center value) of the detected axle load are detected. By correcting the obtained deviation at the position of the load cell of the last stage with respect to the axle load which is the detection output of the load cell, a load equivalent to the stationary axle load of the traveling vehicle can be obtained as a measured value. It was done.

Therefore, it is possible to correct the axle load of the running vehicle which vibrates due to the influence of the road surface unevenness or the like and accurately measure the true axle load. In the above-described example, the load cells 1a and 1b are at the last stage. However, if the tendency of the shaft vibration is known, even if the load cells 1a and 1b are at the forefront, the deviation at the load cell position is obtained. The true axle load can be obtained by correcting the axle load detection value of the vehicle using the load cell. An example is shown in FIG. 7 and will be described as a second embodiment.

(Second Embodiment) In the second embodiment, the system configuration may be the same as that of FIG. FIG. 7 shows that the load cells 1a and 1b are arranged at the frontmost position of the vehicle measurement area on the road 3, and a plurality of piezo sensors 2a, 2b, 2c,..., 2m,.
2n are arranged at regular intervals up to the last stage position of the area. Therefore, in the case of this example, the final stage sensor is the piezo sensor 2n.
It is.

In the configuration of FIG. 7, the load cells 1a,
1b, the piezo sensors 2a, 2b, 2c,.
When the detection outputs of 2m,..., 2n-1 and 2n are completed, the same processing as described above may be performed.

That is, suppose that the vehicle 4 travels and passes through the area of the road 3 where the sensor is laid.
At this time, the vehicle 4 includes the load cells 1a,
1b first, then the piezo sensors 2a, 2
., and finally the piezo sensor 2n.

At this time, the load cells 1a,
A signal corresponding to the received tread pressure is obtained from 1b and each of the piezo sensors 2a, 2b, 2c,... 2n.

These signals are sent to A / F via I / F 21.
The signal is input to the D converter 22, where it is converted into a digital signal (quantized data). This is the vehicle axle load sampling by the plural piezo sensors (step S in FIG. 3).
1) As a result, quantized data like L in FIG. 4 is obtained.

In this manner, the changing axle load of the passing vehicle 4 due to the influence of the road surface unevenness or the like is determined by the piezo sensor 2.
a, 2b, 2c,... are respectively extracted as instantaneous values at the time of passage, and while the load cells 1a, 1b are receiving a load, they are extracted corresponding to the load.
3 to be converted into quantized data. The quantized data obtained from the detection outputs of the piezo sensors 2a, 2b, 2c,... And the quantization data L obtained from the detection outputs of the load cells 1a, 1b are stored in a memory (not shown), and the piezo sensors 2a, 2b, 2c,. Load cell 1
When the quantized data of “a” and “1b” are completed, the arithmetic processing unit 2
3 starts processing.

That is, the piezo sensors 2a, 2b, 2
The instantaneous values of the quantized data of c,.
Is processed as follows. In the arithmetic processing unit 23,
First, the input is converted into continuous data of quantized data by a plurality of polynomial approximations (step S2).

As a result, the obtained data is continuous data denoted by reference numeral D1 shown in FIG. In this way, the quantized data (outputs of the piezo sensors 2a, 2b, 2c,...) Are converted into continuous data D1 as shown in FIG.
Convert to

Next, the arithmetic processing unit 23 outputs the continuous data D1
For the frequency components f1, f2, f
.. Are extracted (step S3). Frequency components (A: amplitude, f: frequency, φ: phase) extracted from the obtained continuous data D1 by the frequency analysis method are, for example, as shown in FIG.
It is as shown in FIG.

Next, the arithmetic processing section 23 performs a re-synthesizing process of the dynamic shaft weight waveform Wrs (step S4). That is, the arithmetic processing unit 23 obtains the obtained frequency components f1, f2, f3,.
, The dynamic axis double waveform Wrs is re-synthesized by executing the processing of the above equation (1) (see FIG. 7;
The dynamic axis weight waveform W recombined with the dotted line indicated by rs
rs).

Next, the arithmetic processing unit 2
In step S5, the deviation ys is obtained, and the stationary axle weight W of the vehicle is obtained from the deviation ys (step S5). That is, the arithmetic processing unit 23 performs a process of obtaining the stationary axle load W of the vehicle, which is based on the axle load sample value L by the load cells 1a and 1b and the vehicle dynamic axle load vibration center value in the load cells 1a and 1b. Is obtained by the calculation of the above equation (2) using the deviation ys.

Then, the obtained stationary axle weight W is output to the output unit 2.
5 and displayed or printed, or stored in a storage means. In this way, the axle weight of the traveling vehicle is provided at a forefront position in front of the piezo sensor arrangement area and a plurality of piezo sensors for detecting the tire tread pressure of the vehicle arranged at regular intervals in the traveling direction of the vehicle on the vehicle traveling road surface. The state of fluctuation of the axle load and axle vibration of the traveling vehicle is detected by the detection outputs of a plurality of piezo sensors, and the average value (center value) of the fluctuation tendency and the detected axle load is detected. By correcting the deviation at the position of the load cell at the preceding stage with respect to the axle load that is the detection output of the load cell, a load equivalent to the stationary axle load of the traveling vehicle can be obtained as a measured value. is there.

Accordingly, the true axle load can be accurately measured by correcting the axle load of the running vehicle vibrating due to the influence of the road surface unevenness or the like. Note that, in this example, the load cell is used as the load determination sensor, and the arrangement position of the piezo sensor farthest from the load cell is set as the origin, as in the example on the left.

Further, the present invention is not limited to the above-described embodiment, but can be carried out by appropriately modifying it without departing from the gist thereof. For example, in the above embodiment, an example is shown in which a piezo sensor or a load cell is used as a load sensor.
The present invention can also be implemented using other load sensors.

[0047]

As described in detail above, according to the present invention,
It is possible to provide a vehicle weight measurement method and a vehicle weight measurement device that can correct the axle load of a running vehicle that vibrates due to the influence of road surface irregularities and can accurately measure the true axle load.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining the present invention, illustrating an example of a road surface arrangement of sensors in a system of the present invention.

FIG. 2 is a diagram for explaining the present invention, and is a diagram for explaining a configuration example of the system of the present invention.

FIG. 3 is a diagram for explaining the present invention, and is a flowchart for explaining the flow of processing of the system of the present invention;

FIG. 4 is a diagram for explaining the present invention, and is a diagram for explaining an example of processing according to the first embodiment of the present invention.

FIG. 5 is a diagram for explaining the present invention, showing an example of frequency components obtained by frequency analysis in the system of the present invention.

FIG. 6 is a diagram for explaining the present invention, and is a diagram for explaining the operation of the system of the present invention.

FIG. 7 is a diagram for explaining the present invention, and is a diagram for explaining processing according to the second embodiment of the present invention.

FIG. 8 is a diagram for explaining a conventional example.

[Explanation of symbols]

1a, 1b: Load cell bending plate (load cell) as a load sensor 2a, 2b, 2c, ... Piezo sensor as a load sensor 3 ... Road surface 4 ... Vehicle 21 ... I / F (interface) 22 ... A / D (analog / digital) Converter 23: arithmetic processing unit 24: output unit.

Claims (3)

[Claims] In a vehicle weight measuring method for measuring the weight of a vehicle using a load sensor, a plurality of load sensors are sequentially installed in a traveling direction of the vehicle, and a load determination sensor among the plurality of load sensors is arbitrarily set. At the same time, the sensor at the origin position is arbitrarily set, a polynomial approximation is performed from the load data detected by each load sensor when passing through the vehicle, and n obtained by frequency analysis of an approximate polynomial in which the origin is the phase origin. The i-th frequency fi of these frequencies, its amplitude Ai, phase φi, the distance x from the origin to the load determination sensor, and the vehicle speed v A vehicle weight measuring method characterized in that a correction weight ys is obtained by the following formula, and a vehicle weight W is obtained from the obtained correction load ys and the load L detected by the load determination sensor by W = L-ys. . 2. A vehicle weight measuring device for measuring a weight of a vehicle by a load sensor, comprising: a plurality of load sensors arranged in a vehicle traveling path in a traveling direction of the vehicle; The load determination sensor and the sensor corresponding to the origin position are set arbitrarily, and a polynomial approximation is performed from the load data detected by each load sensor, and the frequency is analyzed by frequency analysis of an approximate polynomial in which the origin is the phase origin. The i-th frequency fi of the obtained n frequencies, its amplitude Ai, phase φi, the distance x from the origin to the load determination sensor, and the vehicle speed v , A correction load ys is obtained, and the obtained correction load ys and
A vehicle weight measuring device, comprising: a calculating means for obtaining a vehicle weight W from the load L detected by the load determination sensor at W = L-ys. 3. A plurality of piezo sensors for detecting a tire tread pressure of a vehicle having an axle weight of a running vehicle arranged at equal intervals in a traveling direction of the vehicle on a vehicle traveling road surface, and a piezo sensor arrangement area on the vehicle traveling road surface. Following the step position, or a load cell for tire tread pressure detection to be laid and laid in front of the piezo sensor placement area, and detecting the state of fluctuation of the axle load and axle vibration of the traveling vehicle with detection outputs of a plurality of piezo sensors, The stationary shaft of the traveling vehicle is corrected by correcting the deviation at the position of the load cell at the last stage obtained from the tendency of the fluctuation and the average value (center value) of the detected axle load with respect to the axle load obtained from the load cell. And a calculating means for obtaining a load equivalent to the weight as a measured value.