JPH09311050A - Detector for traveling position of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a detector for the traveling position of a vehicle, whose execution and control are comparatively simple, which detects the position of the vehicle exactly and which can correct the position when an error is generated in the position. SOLUTION: A running road 6 is divided into a plurality of sections, and position data on every section is prepared in advance as a table. A pin 5 is installed on the running road, and a potentiometer 4 is operated whenever a vehicle 1 is passed through the pin 5. A voltage which is different in every section is output, and the traveling section of the vehicle 1 is specified by referring to the table on the basis of its voltage value. A position inside the section is specified by the number of pulses of a rotary encoder 2, which are outputted in synchronization with a wheel 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a position detecting device for detecting a traveling position of a vehicle traveling on a predetermined route.

[0002]

2. Description of the Related Art Conventionally, the traveling position of a vehicle that travels unmanned along a predetermined route by remote control or the like can be obtained as a traveling distance from a reference position by integrating the rotational speeds of wheels. However, in this method, an error was caused in the traveling distance due to the slip of the tires, which are the wheels, and the change in the ground contact diameter, and accurate measurement could not be performed. Therefore, in order to detect the traveling position more accurately, markers that can be identified by sensors are installed at regular intervals on the traveling route, and each time the vehicle passes the marker, the sensor mounted on the vehicle detects the marker. However, a method is used in which the traveling distance accumulated from the wheels is corrected at that timing.

However, also in this case, the traveling distance, which is separately obtained at the timing when the sensor detects the sign, is only corrected, and the traveling position, that is, the absolute position of the vehicle cannot be obtained only by detecting the sign. It was In addition, when detecting the position, it is necessary to return the vehicle to the origin first, which makes the operation troublesome. Furthermore, the installation position of the sign on the traveling route must be accurate, which increases the burden of construction and management. Further, if there is an error in detecting the sign of the sensor, an error will be accumulated in the traveling distance thereafter.

Therefore, the following improvements are proposed in which these problems are further improved. That is, the interval between signs is set arbitrarily, a code indicating the installation position is added to the sign itself, the sign is detected by a sensor, and the code is read, and the total traveled distance is calculated based on the code contents. The correction is made.
In this method, when detecting the vehicle position prior to the start of traveling, it is sufficient to move to the position of the sign before and after that, and since it is not necessary to install the signs at equal intervals, construction and management are easy. Become. Further, even if the sensor may not detect the object when passing the sign, the traveling distance is corrected by the next sign, so that there is no possibility of accumulating an error.

[0005]

However, this method has a problem that the equipment cost becomes high because the code is added to the sign and a sophisticated sensor capable of reading the code is required. The present invention has been made to solve the above problems, and the object thereof is to accurately detect the position of a vehicle and to make an error in the position even though the construction and management are relatively simple. In this case, it is an object of the present invention to provide a vehicle traveling position detecting device capable of correcting it.

[0006]

In order to solve the above problems, the invention of claim 1 divides the traveling road into a plurality of sections and installs a dock on the boundary of the sections. On the other hand, a dock detection mechanism is provided on the vehicle that contacts the dock every time the vehicle passes the dock, and intermittently rotates in the forward and reverse directions corresponding to the passing direction, and the input shaft of the potentiometer is connected to the dock detection mechanism. , A sensor is provided on the vehicle to detect that the vehicle has passed the dock along with the passing direction,
Further, a rotary encoder is provided which generates a pulse in synchronization with the rotation of the wheels. In addition, a buffer for storing the traveling distance calculated from the output pulse of the rotary encoder, a potentiometer output voltage value for each section of the traveling path, and the section length are prepared as a table.

Here, when the vehicle travels and passes the dock, the dock detection mechanism operates, the rotary shaft of the potentiometer is intermittently rotated according to the traveling direction, and the output voltage of the potentiometer changes stepwise. . Based on the value of this voltage, the section in which the vehicle is traveling is specified by referring to the table. Here, if the vehicle passes the dock in the forward direction, reset the counter and then
The traveling distance is calculated based on the number of pulses output from the encoder, and the value in the buffer is added. Also, when the vehicle passes the dock in the opposite direction, the section length for the new section is read from the table and set in the counter, and then the traveling distance is calculated based on the number of pulses output from the rotary encoder. Value in the buffer is subtracted. As a result, the traveling position of the vehicle can be specified as a section corresponding to the output voltage of the potentiometer, and the detailed position in the section can be specified by the value of the buffer.

According to a second aspect of the present invention, in the first aspect of the invention, the voltage value output from the potentiometer for each section while the vehicle is traveling from the forward head section and the number of output pulses of the rotary encoder for each section. The table is created by sequentially writing the section length calculated from the above into the table in association with the section number.

Here, a dock is constructed by a pin supported on a traveling path in a direction orthogonal to the traveling direction, and a driven vehicle that engages with the pin when the pin passes and an output to a potentiometer connected to the driven axle. A worm gear mechanism that reduces the speed, a cam connected to the driven axle, and a cam follower that is pressed and urged by the cam to hold the rotational position of the driven vehicle constitute a dock detection mechanism. It may be installed and used as a sensor for detecting the passage of a vehicle on the dock.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of an embodiment of a vehicle traveling position detecting device according to the present invention. In the figure, 1
Is a vehicle, and travels on the traveling path 6 by wheels 7.
The traveling path 6 is divided into a plurality of sections, and the detected pin 5 which is a dock is arranged at the boundary of the sections. The vehicle 1 is equipped with a mechanical position detection unit 3 that is a dock detection mechanism, and detects that the position of the detected pin 5 has been passed during traveling. A potentiometer 4 is connected to the mechanical position detecting section 3, and each time the vehicle 1 travels and passes a detected pin 5, the mechanical position detecting section 3 detects it and adjusts the potentiometer 4 by a constant angle. Roll or reverse. Further, the vehicle 1 includes a rotary encoder 2 for detecting the number of rotations of the wheels 7.
Is installed.

FIG. 2 is a perspective view showing the structure of the mechanical position detector 3. Pin 5 supported on the traveling path 6
A driven wheel 8 of four blades is supported by a shaft 11 at a position to be engaged with. When the vehicle 1 travels to the right, the pin 5 relatively moves to the left, so the driven vehicle 8 is rotated counterclockwise by the pin 5, and when the vehicle 1 travels to the left, Since the pin 5 moves relatively to the right, the driven wheel 8 is rotated clockwise by the pin 5. On the other hand, axis 1
To the other end of 1 is connected a cam plate 13 having a cam surface formed by dividing one circumference into four equal parts, and a roller 16 pivotally supported by a lever 12 is brought into contact with the cam surface. There is. The tip of the lever 12 is urged toward the cam plate 13 by a spring 14. Therefore, the lever 12 and the roller 16 function as a cam follower, and each time the pin 5 passes and engages with the driven wheel 8, the shaft 11 rotates by 90 degrees and the position thereof is maintained.

Further, a groove type photoelectric switch 15 is installed within the range of rotation of the tip of the lever 12, and the lever 12 swings and operates the photoelectric switch 15 each time the driven wheel 8 rotates. , The passage of pin 5 is detected. At this time, the passing direction of the dock can be determined from the output change of the potentiometer, the output pulse of the rotary encoder 2, and the like.
The worm wheel 10 is engaged with the worm wheel 9, and the input shaft 17 of the potentiometer 4 is connected to the worm wheel 10.
Input shaft 17, the input shaft 17 is intermittently rotated by a constant angle, and the output voltage of the potentiometer 4 changes stepwise. By storing the output voltage value of the potentiometer 4 and each section on the traveling path 6 in advance, the vehicle position can be specified from the output voltage of the potentiometer 4 while the vehicle is traveling.

FIG. 3 is an explanatory view showing the principle of detecting the position of the vehicle 1 using the pin 5 installed on the traveling road 6. As shown in the figure, by arranging _n pins 5 _{1 to} 5 _n on the traveling path 6 at appropriate intervals, the traveling path 6 is divided into n-1 sections. Numbers 1 to n-1 are sequentially assigned to the sections to obtain section values. Each section value corresponds to the output voltage of the potentiometer 4 described above. The length of each section, since not equal to each other, manage the length of each section as the section within a relative value Q ₁ ~Q _n-1. Specifically, the number of pulses output from the running rotary encoder 2 is counted to calculate the relative distance from the reference pin 5.

FIG. 4 is a diagram showing the relationship between the traveling position of the vehicle 1 and the output voltage of the potentiometer 4. When passing through the pins 5 _{1 to} 5 ₄ which are the boundaries of the section, the voltage changes abruptly. , The same voltage is held in each section. Specifically, the voltage V1 in the section 1 and the voltage V2 in the section 2
In the section 3, the voltage V3 is output. FIG. 5 is a block diagram showing the configuration of a calculation unit that detects the vehicle position using the detection signals from the above-described units. The calculation unit is CP
It is composed of a microcomputer including a U21, a memory 22, and the like. In this embodiment, when the vehicle 1 is introduced onto the traveling road 6 after the traveling road 6 as the vehicle traveling system is completed and the pins 5 are installed, first, the position data table creation mode is set. The calculation unit creates a position data table having the contents shown in Table 1 in the memory 22.

[0015]

[Table 1]

That is, the vehicle 1 is stopped at the position of PO in FIG. The point PO is located in the CCW direction with respect to the pin 5 ₁ . The CCW direction is a direction in which the section value and the relative value within the section decrease when the vehicle 1 is moved, that is, the opposite direction,
The CW direction is the direction in which the section value and the relative value within the section increase, that is, the forward direction. Next, the vehicle 1 at the PO point is moved in the CW direction. Each time the pins 5 _{1 to} 5 _n shown in FIG. 3 are detected, the photoelectric switch 15 outputs a section change signal to the CPU 21 and the section length data buffer 23. C
When the PU 21 receives this signal, the relative value counter 2
4 is reset, and the output voltage value of the potentiometer 4 digitally converted by the A / D converter 25 is read.
Further, as the vehicle 1 advances, the rotary encoder 2
The pulses output from are counted by the relative value counter 24, and the values thereof are sequentially sent to the relative value buffer 18.

Next, the vehicle 1 enters section 2 from section 1.
Then, the section change signal is output from the photoelectric switch 15 again.
And sent to the CPU 21 and the relative value buffer 18.
You. Then, the CPU 21 resets the relative value counter 24.
The value of the section length data buffer 23 before being set is C
It is read by the PU 21. Thus, all sections 1 to n-1
Of the potentiometer 4 while passing the
Output voltage value and calculated from rotary encoder 2
By storing the section length data in the memory 22,
Position data table is created. Position data table
Is the output voltage of the digitally converted potentiometer.
Pressure value D₁~ D_n-1, Section value 1 to n-1, section length data Q₁
~ Q_n-1Are written correspondingly. Table
After completion, switch to the normal driving mode and drive
Output voltage value D of potentiometer ₁~ D_n-1And rotary
・ Specify the vehicle position from the count value of encoder 2.
It becomes possible.

Next, a description will be given of the calculation for specifying the vehicle position with reference to the position data table after switching to the normal traveling mode. First, while the vehicle is running,
When the U21 reads the output voltage value of the potentiometer 4 input via the A / D converter 25, the U21 can refer to the position data table and specify the section in which the vehicle is currently traveling as the section value. Further, regarding the position within the section, when the vehicle passes through the pin 5 which is the boundary of the section, the photoelectric switch 15 outputs a section change signal to the CPU 21. Here, the relative value counter 24 is reset while the vehicle is moving in the CW direction. As a result, the relative value counter 24 newly counts the pulses output from the rotary encoder 2, and the count value is sequentially sent to the relative value buffer 18 and latched. As a result, the CPU 21 reads the value of the relative value buffer 18, and the vehicle 1 in the section is read.
The current position of is identified.

When the section change signal is output while the vehicle is moving in the CCW direction, the CPU 21 reads the section length data for the section newly entered by the vehicle 1 from the table and converts it into a count value. Then, the relative value counter 24 is set. As a result, the relative value counter 24
Newly decrements the count value by the pulse output from the rotary encoder 2. The count value is sequentially sent to the relative value buffer 18 and latched. As a result, the CPU 21 reads the value of the relative value buffer 18 to specify the current position of the vehicle 1 in the section.

Next, a method of identifying the vehicle position when the power source of the vehicle is turned off at an arbitrary position on the road and the position data of the vehicle up to that point is erased and then the power source is turned on again will be described. FIG. 6 is an explanatory view thereof, and when the vehicle 1 is powered on from a state where it is stopped at P ₁ in the section N ₁ ,
First, it can be seen from the output voltage of the potentiometer 4 that the current vehicle position is within the section N ₁ by referring to the table. Here, if it is confirmed that the section change signal is not output, the vehicle 1 is moved in the CW direction. When the vehicle 1 passes the pin 5 _x , the photoelectric switch 15 is activated and the section change signal is output.

As a result, the pulses output from the rotary encoder 2 are newly counted after passing through the pin 5 _x , so that the relative value X within the section, which is the current position of the vehicle within the section N ₂ , is The value can be specified by reading the value in the relative value buffer 18. Also, if you need it here,
At the same time as the output of the section change signal, the value of the section length data buffer 23 measured after re-input can be fetched and back calculated from the value to specify the stop position P1. After passing through the pin 5, the normal traveling mode is restored.

In the above embodiment, the following effects were obtained. (L) By adopting the mechanical position detector and the potentiometer, the absolute position of the vehicle can be immediately grasped on a section-by-section basis immediately after the power is turned on again. (2) By mechanically detecting the absolute position of the vehicle,
Compared to using an optical sensor or magnetic sensor,
Not affected by the installation environment. (3) The docks installed on the road have a common structure and use pins with a simple shape. Therefore, the equipment cost is reduced as compared to the conventional example in which a sign with an identification code is installed. Freed from the hassle of construction and management.

The dock is not limited to the pin of the embodiment,
It is also possible to use a flat bar or the like. Further, in the embodiment, the passage of the dock is detected by the photoelectric switch, but as another detection method, a circuit for extracting the output change of the potentiometer may be provided to generate the section change signal.

[0024]

As described above, according to the present invention, position data for each section of the traveling road is prepared in advance as a table, a dock is installed on the traveling road, and a vehicle is passed through the dock. When the potentiometer is activated, the travel section of the vehicle is specified by referring to the table from the output voltage of the potentiometer, and the detailed position within the section is determined by the rotary output that is output in synchronization with the rotation of the wheels for each section. -Specified by the number of encoder pulses. As a result, the structure of the dock installed at each boundary of the section is simple, and the device for detecting the passage of the dock and specifying the section is also simple, so that the equipment can be constructed at low cost. Also, since no code or the like is used for recognizing the section, there are few malfunctions. Even if the section or the position within the section is erroneously recognized, the correction is performed in the next section, so that the error is not accumulated and the reliability is excellent.

Further, regarding the table for storing the position data, the section voltage measured for each section by using the output voltage value of the potentiometer which changes for each section while the vehicle is traveling and the pulse output from the rotary encoder. It is easily created by sequentially collecting and writing.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of a vehicle traveling position detection device according to the present invention.

FIG. 2 is a perspective view showing a configuration of a mechanical position detection unit in FIG.

FIG. 3 is an explanatory diagram showing the principle of detecting the position of the vehicle in the embodiment.

FIG. 4 is a diagram showing a relationship between a traveling position and an output voltage in the embodiment.

FIG. 5 is a block diagram showing a configuration of a calculation unit that detects a vehicle position in the embodiment.

FIG. 6 is an explanatory diagram of a method for identifying a vehicle position when the power is turned on again in the embodiment.

[Explanation of symbols]

1 vehicle 2 rotary encoder 3 mechanical position detector 4 potentiometer 5, 5 _{1 to} 5 _n detected pin 6 traveling path 7 wheel 8 driven vehicle 9 worm 10 worm wheel 11 shaft 12 lever 13 cam plate 14 spring 15 photoelectric switch 16 roller 17 Input Axis 18 Relative Value Buffer 21 CPU 22 Memory 23 Section Length Data Buffer 24 Relative Value Counter 25 A / D Converter

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Setsuo Sato 1-7-1 Yurakucho, Chiyoda-ku, Tokyo Toko Electric Co., Ltd. (72) Hiroyuki Kubo 1-7-1 Yurakucho, Chiyoda-ku, Tokyo East Inside Kodensha Inc.

Claims (3)

[Claims] 1. A dock installed on each section boundary of a travel path divided into a plurality of sections, and a dock that is placed on a vehicle and contacts the dock every time the vehicle passes through the dock, and corresponds to the passing direction. A dock detection mechanism that rotates in reverse intermittently, a potentiometer with an input shaft connected to the dock detection mechanism, a sensor on the vehicle that detects when the vehicle has passed the dock along with the passing direction, and a wheel mounted on the vehicle. A rotary encoder that generates a pulse in synchronization with the rotation of the, a table that describes the output voltage of the potentiometer that changes stepwise according to the traveling position of the vehicle and the corresponding traveling section number and the section length, A buffer that stores the distance from the vehicle's current position to one dock for each section and a table based on the output voltage of the potentiometer are used to refer to the current A means for identifying the row section, a means for resetting the counter each time the vehicle passes the dock in the forward direction, and a counter for reading the section length for the new section from the table each time the vehicle passes the dock in the reverse direction. Set to, while the vehicle is traveling in the forward direction, means for calculating the traveling distance based on the number of pulses output from the rotary encoder and adding the value in the buffer, and the vehicle in the reverse direction. A traveling position detecting device for a vehicle, comprising: means for calculating a traveling distance based on the number of pulses output from the rotary encoder while traveling and subtracting the value in the buffer. 2. The vehicle traveling position detection device according to claim 1, wherein the voltage value output from the potentiometer for each section while the vehicle is traveling from the forward head section and the output pulse of the rotary encoder for each section. A traveling position detection device for a vehicle, comprising means for writing a table into a table in order by associating a section length calculated from the number with a section number. 3. The vehicle traveling position detecting device according to claim 1 or 2, wherein a dock is formed by pins arranged on a traveling road in a direction orthogonal to the traveling direction, and the dock is engaged with the pins when passing through the pins. A driven wheel that is rotated, a worm gear mechanism that is connected to the driven axle to reduce the output to the potentiometer, a cam connected to the driven axle and a cam follower that holds the rotational position of the driven vehicle by being biased by the cam. A vehicle traveling position detection device, characterized in that a dock detection mechanism is configured by the above, and a photoelectric switch is installed in the movement range of the cam follower to serve as a sensor for detecting the passage of the dock of the vehicle.