JP2974933B2 - Vehicle travel position detection device - Google Patents

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 Heretofore, a traveling position of a vehicle that travels on a predetermined route unattended by remote control or the like can be obtained as a traveling distance from a reference position by integrating the number of rotations of wheels. However, according to this method, an error occurs in the running distance due to a slip of a tire as a wheel or a change in a ground contact diameter, and accurate measurement cannot be performed. Therefore, in order to more accurately detect the traveling position, signs that can be identified by sensors are installed at regular intervals on the traveling route, and each time the vehicle passes the sign, the sensor mounted on the vehicle detects the sign. Then, a method of correcting the running distance integrated from the wheels at that timing is used.

However, also in this case, the travel distance separately obtained is only corrected at the timing when the sensor detects the sign, and the travel position, that is, the absolute vehicle position cannot be obtained only by detecting the sign. Was. Further, when detecting the position, it is necessary to first return the vehicle to the origin, so that the operation is troublesome. In addition, the location of the sign on the traveling route must be accurately set, which increases the burden of construction and management. Also, if there is an error in the detection of the sign by the sensor, the error will be accumulated in the subsequent traveling distance.

[0004] In order to solve these problems, the following has been proposed. It is possible to set the sign intervals at random, add a code indicating the installation position to the sign itself, detect the sign with a sensor, read the code, and calculate the accumulated travel distance each time based on the code content. The correction is made.
In this method, when the vehicle position is detected prior to the start of traveling, it is only necessary to move to the position of the sign before and after that, and it is not necessary to arrange the signs at equal intervals, so construction and management are easy. Become. Further, even if the sensor does not detect the signal when passing through the sign, the traveling distance is corrected by the next sign, so that there is no possibility that errors are accumulated.

[0005]

However, this method has a problem that the equipment cost is high because a code is added to the sign and an advanced sensor capable of reading the code is required. The present invention has been made in order to solve the above-mentioned problems, and the object thereof is to detect the position of the vehicle accurately and to make an error in the position while performing relatively simple construction and management. It is an object of the present invention to provide a traveling position detecting device for a vehicle that can correct such a case when the vehicle travels.

[0006]

In order to achieve the above object, a first invention is provided at each boundary of a section of a traveling path divided into a plurality of sections, and the length of the traveling direction is arbitrarily set. A sign that changes, a sensor mounted on the vehicle that detects the sign on the road and outputs a detection signal, a rotary encoder mounted on the vehicle that generates a pulse in synchronization with the rotation of the wheel, and the sensor detects the sign Rotary while doing
Means for counting the pulses generated by the encoder, a table describing the number of pulses counted during the passage of the sign and the corresponding section number, and a section number referring to the table based on the number of pulses counted during the passage of the sign Means for detecting that the vehicle has passed the boundary of the section based on a change in the sign detection signal from the sensor, and means for setting / resetting data to a counter for measuring a pulse generated by the rotary encoder. Means for obtaining the current position of the vehicle from the section number and the number of pulses in the counted section.

According to a second aspect of the present invention, there is provided a sign which is installed at each boundary of a section of a traveling road divided into a plurality of sections and whose length in the traveling direction is arbitrarily changed, and a sign which is mounted on a vehicle and is on a traveling path. A sensor that detects and outputs a detection signal, a rotary encoder mounted on the vehicle that generates a pulse in synchronization with the rotation of the wheel, and counts pulses generated by the rotary encoder while the sensor detects a sign Means, a table describing the number of pulses counted during passage through the sign and the corresponding section number, a means for discriminating the section number by referring to the table based on the number of pulses counted during passage of the sign, and a sensor A section number counter whose count value is increased or decreased based on a change in the sign detection signal from the vehicle and the traveling direction of the vehicle, and a section obtained from the number of pulses passing the sign. Means for comparing the value of the section number counter with the value of the section number counter, and if the values are different, means for correcting the value of the section number counter by the section number obtained from the number of pulses, and Means for setting / resetting data to a counter which detects the passage of the boundary and measures the pulse generated by the rotary encoder, and determines the current position of the vehicle from the value of the section number counter and the number of pulses counted in the section. And means for requesting.

In a third aspect based on the first or second aspect, the section number is incremented and written into the section number column of the table each time the sensor detects a sign when the vehicle starts running from the origin position. Means, means for writing the number of pulses counted while passing through the sign corresponding to this means in the corresponding pulse number column of the table, and means for writing the number of pulses corresponding to that section in the section length column of the table. It is characterized by having.

[0009]

In the first aspect of the present invention, a sign is provided at each boundary of a section of the traveling road divided into a plurality of sections. This sign can be distinguished from other signs by arbitrarily changing the length in the traveling direction. The vehicle is equipped with a sensor that detects a sign on the road and outputs a detection signal and a rotary encoder that generates a pulse in synchronization with the rotation of the wheel. When a sign is detected by the sensor, pulses generated by the rotary encoder while the sign detection signal is being output from the sensor are counted.

In the table, the number of pulses counted while passing through the sign and the corresponding section number are described in advance, and by referring to this table, the section based on the number of pulses counted while passing through the sign is referred to. The numbers are discriminated. On the other hand, when it is detected that the vehicle has passed the boundary of the section due to a change in the sign detection signal from the sensor, data is set / reset to a counter that measures a pulse generated by the rotary encoder. The current position of the vehicle is determined from the discriminated section number and the number of pulses in the counted section.

[0011] In the second invention, a sign is provided at each boundary of a section of the traveling road divided into a plurality of sections. This sign can be distinguished from other signs by arbitrarily changing the length in the traveling direction. The vehicle is equipped with a sensor that detects a sign on the road and outputs a detection signal and a rotary encoder that generates a pulse in synchronization with the rotation of the wheel. When a sign is detected by the sensor, pulses generated by the rotary encoder while the sign detection signal is being output from the sensor are counted.

In the table, the number of pulses counted while passing through the sign and the corresponding section number are described in advance, and by referring to this table, the section based on the number of pulses counted while passing through the sign is referred to. The numbers are discriminated. The count value of the section number counter is increased or decreased according to the timing of the change of the sign detection signal from the sensor according to the traveling direction of the vehicle.

The section number obtained from the number of pulses passing through the sign is compared with the value of the section number counter. If the values are different, the value of the section number counter is corrected by the section number obtained from the pulse number. When it is detected that the vehicle has passed the section boundary by a change in the sign detection signal from the sensor, data is set / reset to a counter that measures a pulse generated by the rotary encoder. The current position of the vehicle is obtained from the value of the section number counter and the traveling distance in the counted section.

In the third invention, when the vehicle starts running from the origin position, each time the sensor detects a sign, the section number is incremented and written in the section number column of the table, and the section number is written while passing the sign. The number of pulses to be counted is written in the corresponding pulse number column of the table, and the pulse number corresponding to that section is written in the section length column of the table.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is an explanatory diagram showing a traveling path, and the starting point O of the traveling path
From ₁ to the end point O _n divided into (n-1) sections, arranged starting, the plate P ₁ to P _n where a label boundary position of the end point and each section. Plate P ₁ to P _n length C ₁ -C _n in the running direction of are respectively set to an arbitrary length. However, there is no one with the same length. Also, sections 1 to n
Section length Q ₁ ~Q _n-1 -1 are each any length.
Here the starting point O ₁ as the origin, the direction from the starting point O ₁ to the end point O _n is called the CW direction, called the opposite direction to the CCW direction.

FIG. 3 is an explanatory view showing the vehicle 1 traveling on the traveling path 5. The vehicle 1 has a rotary encoder 2 and a plate sensor 3 that generate pulses in synchronization with wheels. The plate sensor 3 outputs an H-level detection signal while passing over the plate 4 provided on the traveling path 5. That is, as shown in the waveform diagram of FIG.
While the plate sensor 3 is passing over the plate 4, the output signal of the sensor 3 is at H level. The H-level section T corresponds to the length of the plate 4 in the traveling direction. At this time, since the vehicle 1 is traveling, the rotary encoder 2 outputs a pulse.

That is, the number of pulses in the section T at the H level is a value proportional to the lengths C _{1 to} C _n of the plate 4, and the number of pulses changes if the length of the plate 4 differs. Since then
Each length C _{1 to} C _n of the plate 4 is represented as a pulse number. In the present invention, in advance for each section 1 to n-1, the start point, the length C ₁ -C _n plate 4 disposed at the boundary of the endpoints and segment previously written in the table as shown in FIG. 5, traveling When the sensor 3 detects the plate 4, the number of pulses during the detection of the plate 4 is counted, and the number of the section corresponding to the counted value is obtained by referring to the table.

The section lengths Q ₁ to Q ₁ for each of the sections ₁ to n-1
If Q _n-1 is similarly stored in the table as the number of pulses, the travel distance from the starting point O ₁ to the current section is obtained as the sum of the section lengths between them. Further, the traveling distance in the section is also obtained by detecting the boundary of the section, that is, the start of the section from the timing of the change of the detection signal output by the sensor 3 and counting the output pulses of the rotary encoder 2. FIG. 6 shows a specific example, in which when the vehicle 1 moves from the section m to the section m + 1, the sensor 3
_{Since m + 1} is detected, the number of pulses output from the rotary encoder 2 after its detection timing, that is, after the detection signal changes to the H level, is counted. Value.

In this manner, the absolute position of the vehicle on the traveling road can be obtained as a section number and a relative value within the section. Further, since the present invention is configured as described above, even when the position of the vehicle 1 is unknown, such as when the power is turned on and the traveling of the vehicle 1 is started, the vehicle 1 is moved back and forth to By measuring the length of the plate 4 and referring to the table, the section can be immediately specified. FIG. 7 is a flowchart specifically showing these processing operations.

In FIG. 7, when the stop position of the vehicle 1 is on the plate 4, the output of the sensor 3 is ON (H level).
Therefore, the vehicle 1 is moved in the CCW direction until the output of the sensor 3 is turned off (L level) to retreat once from the plate 4 (S1 to S4). Next, the vehicle 1 is caused to travel in the CW direction, and the number of pulses output from when the output of the sensor 3 is turned on to when it is turned off is counted. The number is read, and writing to the counter 12 is completed (S
5 to S9).

FIG. 1 is a block diagram showing the electrical configuration of the apparatus. As shown, the control unit of the apparatus is a CPU 1
8, a memory 19 connected to the CPU 18 via a bus,
A microcomputer including a section number value counter 12, a section number value buffer 13, a relative value counter 14, a relative value buffer 15, a plate length buffer 16, and a section length buffer 17, a rotary encoder 2, a plate sensor 3, and a relative value pulse. It comprises a generator 6, a section number value pulse generator 9, and a timing generator 10.

When the plate sensor 3 detects the plate 4 installed on the road surface, it sends an H level detection signal to the section number pulse generator 9 and the timing generator 10. When the direction command signal sent from the CPU 18 is the CW direction, the section number value pulse
The UP signal is sent to the section number value counter 12 at the timing of rising from the level to the H level, and the direction command signal is
In the case of the W direction, the DOWN signal is sent to the section number counter 12 at the timing when the detection signal falls from the H level to the L level.

When the direction command signal sent from the CPU 18 is in the CW direction, the timing generator 10 sends a reset signal to the relative value counter 14 at a timing when the detection signal rises from L level to H level, and the direction command signal is In the case of the CCW direction, a relative value write request signal is sent to the CPU 18 at the timing when the detection signal falls from the H level to the L level. Similarly, the timing generator 10 includes the relative value buffer 15 and the plate length buffer 1
6. A timing signal is also generated and sent to the section length buffer 17.

The section number value counter 12 counts up when the section is switched due to the running of the vehicle and the UP signal is sent, counts down when the DOWN signal is sent, and the CPU 18 forcibly changes the count value. . The count value of the section number value counter 12 is sent to the section number value buffer 13 and can be constantly read by the CPU 18. The rotary encoder 2
A pulse is generated in synchronization with the running of the vehicle and sent to the relative value pulse generator 6.

The relative value pulse generator 6 converts the pulse into an UP or DOWN relative value pulse and sends it to the relative value counter 14. The relative value counter 14 counts the input UP or DOWN relative value pulse,
If the traveling direction when the vehicle enters the new section is the CW direction, the detection signal is reset by a reset signal input at the timing of rising from the L level to the H level, the count value is cleared to 0, and the traveling direction is changed. CCW
In the case of the direction, the relative value of the new section is written by the CPU 18 at the timing when the detection signal falls from the H level to the L level. The count value of the relative value counter 14 is stored in the relative value buffer 15 and the plate length buffer 1.
6. The data is sent to the section length buffer 17.

The value in the relative value buffer 15 indicates the relative value of the traveling section of the vehicle, and is read by the CPU 18. The plate length buffer 16 stores the relative value counter 14 only while the detection signal is at the H level by the timing signal.
The count value of is taken in and held as the value of the plate length,
It is read by the CPU 18. Section length buffer 17
Is read by the CPU 18 by taking in the count value of the relative value counter 14 from the start to the end of the section according to the timing signal and holding it as the value of the section length.

When the vehicle is running, the CPU 18 sends a direction command signal in the CW direction or the CCW direction in accordance with the direction of the vehicle to the section number value pulse generator 9 and the timing generator 10.
When the relative value write signal is input, the relative value of the corresponding section is read from the table stored in the memory 19 and written to the relative value counter 14. In addition, the CPU 18 periodically transmits the section number value buffer 13,
The relative value buffer 15, the plate length buffer 16, and the section length buffer 17 are read, and whether or not those values are correct,
It is determined whether or not there is a match between the values, and if there is an abnormality, the section number value counter 12 and the relative value counter 14 are rewritten to correct values.

As a result of these processes, the current position of the traveling vehicle is obtained from the values of the section number value buffer 13 and the relative value buffer 15. Here, the vehicle position can also be displayed as an accumulated traveling distance from the starting point by adding the traveling distance in the section to the sum of the section lengths of the sections on the starting point side.
Also, when an error is included in the pulse of the rotary encoder 2 due to wear or slip of the wheel, the error is included only in the relative value within the section, and the accuracy is maintained on average over the entire length of the traveling road.

When an error is detected in the plate detection by the sensor 3, an error occurrence is detected from the value of each buffer, and the traveling position is corrected when the next plate is detected. Note that the configuration shown in FIG. 1 corresponds to the second invention. In the configuration of FIG. 1, the section number counter 12 does not count the UP signal and the DOWN signal from the section number pulse generator 9, and the CPU 18 refers to the table based on the value of the plate length buffer 16 for the section number. It is also possible to adopt a configuration in which a number is obtained and the number value is written into the section number value counter 12, and this case corresponds to the first invention. When the value of the section number value counter 12 is changed for each section by referring to the table, it is not necessary to arrange the plates 4 in the order of the plate length, so that the work is further facilitated.

Next, creation of a table corresponding to the third invention will be described. The table shown in FIG. 5 is stored in the memory 19, and this table can be automatically created by running the vehicle 1 when the installation of the plate 4 on the traveling path is completed. It starts to move the CW direction from the slightly stops the vehicle 1 at the position of the left than the starting point O ₁ in FIG. When the vehicle 1 reaches the plate P _1, the detection signal of the sensor 3 is inverted to H level. At this time, 1 is entered in the section number column of the first row of the table.
Write.

[0031] Next, read the value C ₁ of plate length buffer 16 When passing through the plate P _1, written in the column of the plate length of the first row of the table. Similarly, the detection signal reaches the next plate P ₂ reads the values to Q ₁ interval length buffer 17 When inverted to H level, write to column section length of the first row of the table. This completes the data collection for section number 1. Thereafter, in the same manner, a table is created by continuously collecting data of section number 2 and thereafter without stopping the vehicle.

In this way, the table is automatically created only by traveling once over the entire section of the travel path, so that the apparatus can be easily started up at the time of construction, and the section of the travel path can be changed thereafter. It becomes easy to deal with. When discriminating the section number with reference to the table based on the value of the plate length buffer 16, since the number of pulses counted due to wheel slip or the like includes an error, in the actual processing, the table closest to the count value is used. Treat the value as the appropriate value.
In the embodiment, a plate is used as a sign. However, a combination of a reflective tape as a sign and a sensor as a photosensor is also possible. Furthermore, although the vehicle travels on a road surface, the present invention can be applied to a monorail vehicle traveling on a rail.

[0033]

As described above, according to the first aspect,
Since a sign whose length in the traveling direction is arbitrarily changed is provided for each section divided into arbitrary lengths, the number of each section is distinguished by reading the sign length. This eliminates the need for attaching a code for identifying the position of each sign or an advanced sensor for reading the sign, thereby facilitating construction and management of sign installation in divided sections. The position of the vehicle in the section is
Since it is calculated from the pulse of the encoder, the absolute position of the vehicle can be obtained from the section number and the position in the section, and even if the sensor detects an error of any sign, the next sign is detected. Since the position is corrected, the position can be detected with high accuracy on average without accumulating errors.

According to the second aspect, the count value of the section number counter is increased or decreased each time the sensor detects the sign, so that the vehicle position can be easily obtained from the count value. In addition, since the value of the section number counter is also corrected by the number of pulses during the passage of the sign, the detection results are maintained with high accuracy by averaging.

According to the third aspect, the relationship between the length of the sign provided for each section and the number of the section is automatically written into the table as the vehicle travels. Therefore, the table is created and written manually. Saves time. As a result, it is possible to relatively easily respond to changes in the traveling route, exchange of signs, and the like.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an electrical configuration of an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a traveling path.

FIG. 3 is an explanatory diagram of a vehicle traveling on a traveling road.

FIG. 4 is a waveform diagram showing a detection signal and a pulse from a sensor.

FIG. 5 is an explanatory diagram showing a configuration in a table.

FIG. 6 is an explanatory diagram showing a relationship between a section and a vehicle.

FIG. 7 is a flowchart showing a processing operation for detecting a plate length.

[Explanation of symbols]

Reference Signs List 1 vehicle 2 rotary encoder 3 plate sensor 4 plate 5 traveling path 6 relative value pulse generator 9 section number value pulse generator 10 timing generator 12 section number value counter 13 section number value buffer 14 relative value counter 15 relative value buffer 16 plate length buffer 17 segment length buffer 18 CPU 19 memory P ₁ to P _n plates

──────────────────────────────────────────────────続 き Continuation of the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) G01C 15/00 G01B 21/00 G05D 1/02

Claims (3)

(57) [Claims] 1. A sign installed at each boundary of a section of a traveling road divided into a plurality of sections and having a length arbitrarily changed in a traveling direction, and a sign mounted on a vehicle and detected on the traveling path. A sensor for outputting a signal, a rotary encoder mounted on the vehicle and generating a pulse in synchronization with rotation of a wheel, a means for counting pulses generated by the rotary encoder while the sensor detects the sign, a sign A table that lists the number of pulses counted during passing through and a corresponding section number, means for referring to the table based on the number of pulses counted during passing a sign to discriminate the section number, and detecting a sign from a sensor Detecting that the vehicle has passed the boundary of the section by the change of the signal, set / reset the data to the counter which measures the pulse generated by the rotary encoder. Stage and, discriminated interval number and counted traveling position detecting device for a vehicle, characterized by comprising, means for determining the current position of the vehicle from the number of pulses in the interval. 2. A sign installed at each boundary of a section of a traveling road divided into a plurality of sections and having a length arbitrarily changed in a traveling direction, and a sign mounted on a vehicle and detected on a traveling path. A sensor for outputting a signal, a rotary encoder mounted on the vehicle and generating a pulse in synchronization with rotation of a wheel, a means for counting pulses generated by the rotary encoder while the sensor detects the sign, a sign A table that lists the number of pulses counted during passing through and a corresponding section number, means for referring to the table based on the number of pulses counted during passing a sign to discriminate the section number, and detecting a sign from a sensor A section number counter whose count value is incremented or decremented based on the signal change and the traveling direction of the vehicle, and a section number and section obtained from the number of pulses passing through the sign A means for comparing the value of the number counter and correcting the value of the section number counter with the section number obtained from the pulse number if the value is different, and a vehicle passing the section boundary due to a change in the sign detection signal from the sensor Means for setting / resetting data to a counter which measures the number of pulses generated by the rotary encoder upon detecting the occurrence of the operation, means for determining the current position of the vehicle from the value of the section number counter and the number of pulses counted in the section. A travel position detection device for a vehicle, comprising: 3. The travel position detecting device according to claim 1, wherein the section number is incremented each time the sensor detects a sign when the vehicle starts traveling from the origin position. And a means for writing the number of pulses counted while passing through the sign corresponding to the means in a corresponding pulse number column of the table.