JPH05249127A - Arithmetic unit for calculating speed and movement distance of traveling object - Google Patents

Abstract

PURPOSE:To obtain such an arithmetic unit for calculating speeds and movement distances of a traveling object that the unit can accurately calculate the speed and moving distance of an traveling object even when the object makes racing, slipping, etc., the current wheel diameter data of the object can be automatically set, and a measured wheel diameter value can be adopted as it is. CONSTITUTION:The title arithmetic unit is provided with noncontact speedmeters 21 and 22 which measure the speed of a wheeled traveling object as an absolute speed in a non contact state and at least two speed generators 7 and 8 which detect the speed of the object from the rotation of the wheels of the object. In addition, the arithmetic unit is also provided with a higher priority circuit which inputs the detecting values of the generators 7 and 8 and selectively outputs the higher one of the two detecting values and an arithmetic block which calculates at least either one of the speed and movement resistance of the object based on the output of the higher priority circuit and absolute speeds of the speedmeters 21 and 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed / moving distance calculating device for a moving body capable of measuring at least one of the speed and the moving distance of the moving body such as a railway vehicle.

[0002]

2. Description of the Related Art FIG. 9 is a block diagram showing an outline of a conventional railway train security system. In the figure, reference numeral 1 denotes a main body of an automatic train stop device with a pattern (ATS-P), and inside thereof, it is composed of four blocks of a receiving unit 2, a speed checking unit 3, a relay unit 4, and a recording unit 5.

The receiving part 2 is connected to a car train that receives a telegram from the ground, and the speed checking part 3 outputs speed generators 7 and 8 (hereinafter referred to as SG1 and SG2) that output the speed frequency of the train.
Is installed. The wheel diameter of the train is necessary for speed calculation, and this wheel diameter is usually 860φ when newly manufactured, and the time for wheel replacement is when it becomes 780φ or less.

For this reason, the wheel diameter setting board 9 is required for the speed checking unit 3, and usually the wheel diameters are printed on the wheel diameter nameplate 10 at a pitch of 10 mm. Do in. The wheel diameter set by the switch 11 serves as a basis for speed calculation and distance calculation in the speed checking unit 3.

As shown in FIG. 10, the speed calculation and the distance calculation in the speed checking unit 3 thus constructed are SG17 and SG2.
8, the speed frequencies output by the two speed generators are input to the high priority circuit 12. This is a double system in consideration of a case where one of SG1 and SG2 causes a wire breakage trouble or a fork breakage trouble and the speed signal output is not output.

The high-priority circuit 12 is constructed so that the one with a higher frequency is always adopted, and the output of the high-priority circuit 12 is transmitted to the speed calculation block 13 and the distance calculation block 14, respectively. It is designed to do calculations.

[0007]

The distance calculation and the speed calculation of the security device constructed as above have the following two problems. The first problem is as follows. FIG. 11 is a graph showing a running curve of a train. The OA part is a power running part, AB is a coasting part, and BC is a brake part. In FIG. 11, the X portion is a portion that shows idling.
Although the true value of the train speed is the dotted line part, SG1, SG2
When the wheels of the train with one of the
Due to the action of the high priority circuit 12 of 0, a high frequency is adopted. Therefore, here, a large error will occur in the speed calculation and the distance calculation.

Further, the Y portion in FIG. 11 is a portion showing gliding. In particular, this is a case in which a wheel equipped with either SG1 or SG2 does not rotate in synchronism with the train due to the braking force and the frictional force, even though the train is progressing especially on a rainy day. In practice, it may happen that the wheels are completely locked for 150 to 180 seconds and the speed becomes zero.

In such a case, SG1, SG
If either one of the two is operating normally, the high-priority circuit 12 in FIG. 10 can calculate the normal speed and the distance. However, if the two axes to which SG1 and SG2 are attached slide at the same time, an error will naturally occur.

FIG. 12 is an explanatory diagram for the method of processing the X portion of FIG. When a train runs idle, the wheel rotation speed may generate a speed exceeding the maximum speed of the train in a short time and the emergency brake may be applied. Therefore, in such a case, it is assumed that the speed will increase or decrease at a rate of acceleration of 6 kW / h or 6 km / sec and deceleration of 6 km / h or 6 km / sec based on the experimental results of actual railway vehicles. , Distance calculation is performed. Therefore, the speed correction block 15 in FIG.
Is used for. The conventional speed detection method using the rotation of the axle described above causes a large error as long as there is slipping. This is the first problem. The second problem is the wheel diameter correction problem. The relationship between the vehicle speed and the speed frequency f is expressed by the following equation.

[0011]

[Equation 1] Here, V is the speed kW / h, Z: the number of SG gears (frequency per SG rotation) D is the wheel diameter (mm)

[0012] In the equation (1), the speed frequency f is inversely proportional to the wheel diameter D. If it is a human error, 860φ
If it is mistaken for 850φ, the error is 860/850 = 1.
It is 012, which is 1.2%. This means that if the vehicle travels 10 km, a distance error of 120 m will occur. Also, if a wheel diameter of 855φ is set to 860φ as an inevitable problem, the error is 0.58% at 860/855 = 1.0058. This means that if the distance is integrated, a distance integration error of 58 m will occur after traveling 10 km. It is 5.8 m even after traveling 1 km. This must be said to be a major contradiction in times when high-density driving vehicles require station stop accuracy of ± 25 cm.

The object of the present invention is that the speed calculation and the distance calculation can be accurately obtained even during the operation of a moving body such as idling, and the current wheel diameter data is set manually rather than manually. Another object of the present invention is to provide a speed / movement distance calculation device for a moving body, which can adopt the measured value as it is for the wheel diameter numerical value.

[0014]

In order to achieve the above object, the present invention is configured as follows.

The invention according to claim 1 is a non-contact speed detecting means for measuring the speed of the moving body as an absolute speed without contacting the moving body having wheels, and the speed of the moving body based on the rotation of the wheels. Of at least two speed generators for detecting the above, and a high-priority circuit for inputting the detection values of each speed generator and selectively outputting the one with a higher value, and the output of this high-priority circuit and the non-contact The calculating means is provided for calculating at least one of the speed and the moving distance of the moving body based on the absolute speed of the speed detecting means.

The invention corresponding to claim 2 is a non-contact speed detecting means for measuring the speed of the train as an absolute speed in a non-contact manner with a moving body having wheels, and the speed of the moving body from the rotation of the wheels. With at least two speed generators that detect the speed, a high-order priority circuit that inputs the detection values of each speed generator, and selectively outputs one with a higher value, and a fixed distance on the traveling path of the moving body. From the installed ground element and the moving body detector installed on the moving body, a wheel diameter calculating means for calculating a wheel diameter, a wheel diameter calculated by the wheel diameter calculating means, and the non-contact speed detecting means. Of the absolute speed and a calculating means for calculating at least one of the speed and the moving distance of the moving body based on the output of the high priority circuit.

[0017]

According to the invention corresponding to claim 1, since the absolute speed of the moving body is detected by the non-contact speed detecting means, this is used as the reference speed, and the higher one of the outputs of the speed generator is selected. Since one of the speed and the moving distance of the moving body is obtained by the above, speed calculation and distance calculation can be accurately performed.

According to the invention corresponding to claim 2, the wheel diameter is calculated, and this wheel diameter, the reference speed which is the absolute speed obtained in the same manner as in claim 1, and the higher one of the outputs of the speed generator. Since the velocity and the moving distance of the moving body are obtained based on the above, these can be obtained accurately, and therefore errors in the velocity calculation and the distance calculation due to idling and sliding can be removed.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a moving body speed / moving distance calculation apparatus according to the present invention. Here, an example applied to a railway train security device will be described.
Compared with the conventional example of FIG. 9, a non-contact speed detecting means including a non-contact speedometer detecting section 21 and a non-contact speedometer output circuit 22 is added, and a ground signal detecting element 23 such as a proximity switch is provided. In each case, a signal is input to the speed checking unit 3.

Of these, the non-contact speed detecting means is a means for accurately calculating the error during slipping, and the ground signal detecting element 23 is for removing the error due to the wheel diameter setting. .. First, a method of removing an error during slipping will be described. The non-contact speedometer is being researched and developed for the purpose of obtaining the absolute speed of the vehicle.
There are a laser Doppler method and a microwave Doppler method. There is a principle of. Here, the principle of the laser Doppler method will be described with reference to FIG.

When the laser light is applied to the rail moving at the relative speed V at the angle θ, the frequency of the light scattered in the same direction as the applied light is f _d , which is shifted by the Doppler frequency.

[0022]

[Equation 2] Here, f _d is the Doppler frequency, the f _o frequency of the irradiated light, C is the speed of light, V is the relative velocity of the rail and the vehicle, theta is the angle of the rails with the irradiation light.

When a part of the scattered light that has undergone the Doppler shift and the irradiation light are mixed by the beam splitter, light that has been modulated at the Doppler frequency can be obtained. The speed can be obtained by inputting this signal into a photodetector, converting it into a Doppler signal, and measuring the center frequency thereof. The principle of the microwave Doppler method will be described with reference to FIG. This is a method that uses the same principle as the laser Doppler method using microwaves.

The output from the microwave oscillator passes through the coupler and the horn antenna and is irradiated on the rail surface, and the scattered wave is received by the same horn antenna. From this, a Doppler signal is obtained by guiding it to a mixer through a coupler, mixing it with part of the output from the microwave oscillator, and detecting it. The velocity is obtained by obtaining the center frequency.

In the above-described embodiment, since the error appears as an influence error of the vehicle body vibration and the unevenness of the rail, the speed error as a whole is about ± 1 km / h to 1.5 km / h, and the current speed detection system. Compared with the above, there is a high cost aspect, and it still needs time to be widely adopted for railway vehicles as the main speed detection by itself. In the present embodiment, the non-contact speed detectors SG1, S
This is a system adopted for determining the output signal of G2.

FIG. 4 is a block diagram showing the structure of the speed calculation and distance calculation means of FIG. SG17 in the figure,
The speed frequency generated from SG28 is input to the speed signal determination circuit 16. The non-contact speed signal detection unit 21 is input to the speed signal determination circuit 16 via the output circuit 22 thereof. The output of the determination circuit 16 becomes a formal signal for the speed calculation means 13 and the distance calculation means 14. FIG. 5 is a flow chart showing the function of the speed signal determination circuit 16. As shown in this flowchart, the determination circuit 16 has the following functions.

(1) There is a function of checking whether the outputs of SG1 7 and SG2 8 and the output SG _NC of the non-contact speedometer 21 are normally output (S1, S2, S).
3). (2) The reference is strictly the non-contact speed signal detection unit SG _NC , and the one with a smaller relative difference from SG _NC is selected (S4.
S5, S6).

(3) If SG1 and SG2 exceed the error range of SG _NC (± 1.5 km / h in the embodiment), S
G1 and SG2 are considered to be spinning and gliding at the same time, and the value of SG _NC is adopted (S7, S8, S9, S1).
0, S11). FIG. 6 shows how the speed of the solid line is selected by the action of the non-contact speed detector and the speed signal determination circuit 16 even if slipping or sliding occurs in X and Y. With the above-described configuration, correct speed calculation value and distance calculation value can be obtained even in the case where the speed signal becomes abnormal such as slipping or sliding. FIG. 7 is an explanatory diagram of a method for automatically setting the wheel diameter.

In FIG. 7A, the ground signal detecting element 23 is attached under the floor of the train 30. This is, for example, a device such as a proximity switch, which is further separated from the ground (for example, between rails) at a certain distance l such as an iron piece 31.
A and 31B are installed.

When the train 30 progresses and the detection element 23 faces the ground element 31A, a pulsed signal is generated in the ground signal detection element, and the counting of the speed frequency is started from there. This count continues until the train 30 advances by 1 and faces the ground element 31B. In the embodiment, the speed checking unit automatically calculates the wheel diameter D by the pulse count when the train 30 travels a certain distance l. That is, when the frequency count value when the distance 1 is advanced is n _p , the distance l _p per count value can be expressed by the equation (3).

[0031]

[Equation 3] Assuming that the number of gears of the speed generators SG1 7 and SG2 8 is Z, the wheel diameter D can be calculated as follows.

[0032]

[Equation 4]

Thus, if the wheel diameter D obtained by the equations (3) and (4) is stored in the memory and used, the first digit of D is 0.
-9 can be selected arbitrarily, and an accurate value without rounding off can be obtained.

When the equation (1) is calculated using the values thus obtained, the error in principle becomes 0, and even if the vehicle travels a distance of 1 km, it becomes an error of only a few centimeters. Using such a value, the ATS or the like can perform brake control and coasting control at specified points in the calculation pattern, and the arrival stop accuracy and the like can be dramatically improved. By using the arithmetic unit described above, it is possible to remarkably improve the performance of the automatic train operation device (ATO), the fixed point stop control device (TASC), and the recently developed driving support device. As shown in FIG. 4B, one ground element 31 is provided and the ground element detection element 23 is provided.
The same applies to A, 23B, and two.

The non-contact velocity detecting means of the above-described embodiment is not limited to the laser Doppler method or the microwave Doppler method, but may be any one of the spatial filter method, the crossing guide wire method and the proximity switch method.

The principle of the spatial filter method is shown in FIG. An image of the rail surface is formed on the fence-shaped silicon photodiode by using an objective lens. Train is on rail surface and relative speed V
, The fence-shaped silicon photodiode light image moves at a speed of mV, where m is the magnification of the optical system. When the fence pitch is a, the period T of the output pulse from the fence-shaped silicon photodiode is given by equation (5).

[0037]

[Equation 5] Here, T is the period a of the output pulse fence pitch Sakujo silicon photodiode, m is the magnification of the optical system, when V represents the train and the relative speed of the rail (5) at a frequency f _s, the following ( It becomes the formula 6).

[0038]

[Equation 6] By measuring the center frequency of the output signal of the fence-shaped silicon photodiode, the relative speed V between the train and the rail can be obtained. The principle of the cross induction wire method is that a cross pitch induction wire with a constant pitch is stretched between rails, and an alternating signal current is passed through this to create a magnetic field.

This is a method in which a pickup coil is attached to a train and the induced electromotive force generated in the coil when traveling on a cross induction wire is converted into pulses by a waveform shaping circuit and speed is converted by a digital signal processing circuit.

The principle of the proximity switch method is that metal pieces are installed between rails at a constant pitch, a proximity switch is attached to a train, and the metal pieces are opposed to each other with a constant gap. The oscillation circuit inside the switch stops, and the operation of oscillating when there is no metal piece under the proximity switch is repeated. This is a method in which the speed of this operation signal is converted by a digital signal processing circuit.

[0041]

According to the present invention, the speed calculation and the distance calculation can be accurately obtained even during the operation of a moving body such as idling, and the current wheel diameter data is not manually set. It is possible to provide a moving body speed / moving distance calculation device that can be automatically set and that the measured value can be directly adopted as the wheel diameter numerical value.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of an embodiment of a moving body velocity / moving distance calculation apparatus according to the present invention.

FIG. 2 is a principle diagram of a laser Doppler method of the non-contact speedometer detection unit of FIG.

3 is a principle diagram of the microwave Doppler method of the non-contact speedometer detection unit of FIG.

FIG. 4 is a block diagram for explaining a speed distance calculating unit in FIG.

5 is a travel curve calculated in the embodiment of FIG.

6 is an explanatory diagram of a speed signal determination circuit of FIG.

FIG. 7 is an explanatory diagram of automatic wheel diameter setting of FIG. 1.

FIG. 8 is a principle diagram of the spatial filter method of the non-contact speedometer detection unit in FIG.

FIG. 9 is a block diagram showing a schematic configuration of an example of a conventional speed / movement distance calculation device.

10 is a block diagram of speed calculation and distance calculation of FIG.

FIG. 11 is a travel curve calculated in the example of FIG.

FIG. 12 is a principle diagram of speed calculation during idling according to the example of FIG. 9;

[Explanation of symbols]

1 ... Main body of automatic train stop device with pattern, 2 ... Receiver, 3
... speed difference section, 4 relay section, 5 recording section, 7, 8 speed generator, 13 speed calculation block, 14 distance calculation block, 16 speed signal determination circuit, 21 non-contact speed meter detection Part, 22 ... Non-contact speedometer output circuit, 23 ... Ground signal detecting element.

Claims (2)

[Claims] 1. A non-contact speed detecting means for measuring the speed of the moving body as an absolute speed in a non-contact manner with respect to the moving body having wheels, and at least two units for detecting the speed of the moving body from the rotation of the wheels. Speed generators, a high-order priority circuit that inputs the detection values of each speed generator and selects and outputs the higher value among them, the output of this high-order priority circuit and the absolute speed of the non-contact speed detection means. And a calculating means for calculating at least one of the speed and the moving distance of the moving body based on the above. 2. A non-contact speed detecting means for measuring the speed of the moving body as an absolute speed in a non-contact manner with respect to the moving body having wheels, and at least two for detecting the speed of the moving body from the rotation of the wheels. , A high-order priority circuit that inputs the detected values of each speed generator, and selectively outputs one with a higher value, and a ground element installed at a certain distance on the traveling path of the moving body, Wheel diameter calculating means for calculating a wheel diameter by a moving body detector installed on the moving body; a wheel diameter calculated by the wheel diameter calculating means; an absolute speed from the non-contact speed detecting means; A moving body speed / moving distance calculating device comprising: a calculating unit that calculates at least one of a speed and a moving distance of the moving body based on an output of a high-order priority circuit.