JPH10105882A - Self-traveling vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent erroneous positional correction due to the reading error of positional information by correcting the position of its own vehicle only when the order of positional information obtained at the time of passing is proper. SOLUTION: When positional information transmitted from a beacon expresses a position directly on a road, an arithmetic controller 5 compares the orders of positional information obtained this time and the last time with each other and when the order of positional information obtained this time is advanced by one, the controller 5 judges positional information obtained this time is proper. Then while successively correcting the detecting position of its own vehicle based on read positional information, the controller 5 obtains an inter-vehicle distance from its own vehicle based on the position of a preceding vehicle received by a communication part 3, calculates a control target valve the speed at which it travels to follow a preceding vehicle so as to allow the obtained inter-vehicle distance to be a previously set inter-vehicle distance and properly gives a driving command to the accelerator driving part 6 and the brake driving part 7 of its own vehicle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic traveling vehicle that automatically travels on a road while recognizing a position on the road on which the vehicle is traveling.

[0002]

2. Description of the Related Art Recently, when a vehicle is automatically driven at a predetermined speed on a dedicated road on which facilities for automatic driving are installed,
The position on the road on which the vehicle is traveling is detected, the position of the preceding vehicle is known through inter-vehicle communication, and the inter-vehicle distance to the preceding vehicle is obtained from the position of the own vehicle at that time, and the obtained inter-vehicle distance is determined in advance. A device has been developed in which the traveling speed of the own vehicle is controlled so as to achieve a set inter-vehicle distance.

However, at this time, it is undeniable that a position error occurs when detecting the position on the road on which the vehicle is traveling.
The position error directly lowers the accuracy of followability with respect to the preceding vehicle, so that it is necessary to correct the detected position.

In this case, position information providing means is locally installed on the road to obtain position information when the vehicle passes through the installation location, and to correct the position detected at that time. It can be considered. But,
Even in such a case, if there is an error in reading the position information, the position is not correctly corrected, and the control for keeping a constant inter-vehicle distance with respect to the preceding vehicle deviates.

Conventionally, as an approximation method, the estimated position of the vehicle determined by dead reckoning navigation is received from beacon equipment installed locally on the road, and information on the position on the road is received to correct the estimated position. There is a navigation device designed to perform this operation (see Japanese Patent Application Laid-Open No. 5-142996).

[0006] According to this, for example, when traveling on a general road that crosses an expressway at an overpass, it is prevented that the position information is received from the beacon for the expressway and the erroneous estimation position is corrected. Therefore, the information of the road direction is included in the information by the beacon, and the traveling direction of the own vehicle detected by the on-vehicle sensor and the road direction obtained from the received information are used as the estimated position and the position obtained from the received information. By comparing with the correlation with the position information, the reliability of the position information received at that time is obtained, and the determination as to whether or not to adopt the position information is performed.

[0007]

The problem to be solved is that an automatic traveling vehicle that automatically travels while finding the position on the road on which the vehicle is traveling and recognizing the position of the vehicle on the road. The location information providing means is locally installed on the road, and the location information is obtained when the own vehicle passes through the installation location, and the position of the own vehicle detected at that time is corrected. When reading, if there is an error in reading the location information,
The control may deviate in a case where the position correction is not performed correctly and the control for the inter-vehicle distance to the preceding vehicle is performed at a constant distance.

[0008]

SUMMARY OF THE INVENTION According to the present invention, there is provided an automatic traveling vehicle which determines a position on a road on which the vehicle is traveling and which automatically travels while recognizing the position of the vehicle on the road. When passing through the location of the location information providing means installed locally on the road and obtaining the location information on the road and correcting the position of the own vehicle, an incorrect position correction due to an error in reading the location information In order to prevent this from being done, priorities are included in advance in each position information on the road to be automatically driven, and it is determined whether or not the validity of the order of the position information obtained at the time of passing through the position information adding means is appropriate. Then, only when it is determined that the vehicle is appropriate, the position of the own vehicle is corrected based on the position information.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A description will now be given of a case where the vehicle automatically travels on a dedicated road provided with facilities for automatic traveling while maintaining a constant inter-vehicle distance with a preceding vehicle.

In this case, as shown in FIG. 1, the automatic traveling vehicle according to the present invention detects the position on the road where the vehicle is traveling when the automatic traveling speed of the vehicle is set to a predetermined value. Position detecting unit 1, a communication unit 3 for transmitting and receiving position data between vehicles, a reader 4 for reading a marker M provided with position information locally provided on a road, and a read position While successively correcting the detection position of the own vehicle based on the information, the inter-vehicle distance with the own vehicle was obtained based on the position of the preceding vehicle received by the communication unit 3, and the obtained inter-vehicle distance was set in advance. A control target amount of a speed such that the vehicle follows the preceding vehicle is traveled so as to be the inter-vehicle distance, and drive commands are appropriately given to the accelerator driving unit 6 and the brake driving unit 7 of the own vehicle to drive the own vehicle. Arithmetic controller 5 for controlling speed It is constituted by.

If the speed of the automatic running of the vehicle is not set to a predetermined value, a speed detecting unit 2 for detecting the running speed of the own vehicle is provided. And the transmission and reception of the traveling speed data are performed, and the inter-vehicle distance and the relative speed with respect to the own vehicle are obtained based on the position and the traveling speed of the preceding vehicle received by the communication unit 3. An appropriate inter-vehicle distance is calculated by a predetermined calculation process, and a control target amount of a speed such that the vehicle follows the preceding vehicle while traveling is maintained while maintaining the appropriate inter-vehicle distance. A drive command is appropriately given to the unit 7 to control the traveling speed of the own vehicle.

The position detecting section 1 measures a traveling distance from a starting point on a road dedicated to automatic driving, thereby obtaining a position on the road. At this time, while detecting a row of magnetic nails driven at a fixed interval (1 m interval) along the road to guide the vehicle on a road surface dedicated to automatic driving, a magnetic sensor provided on the vehicle side detects the magnetic nail row. In the case of automatic traveling, the position on the road can be obtained by counting the number of magnetic nails from the starting point.

Further, it is needless to say that the position information of the own vehicle in the on-vehicle navigation device can be used even when the road on which the vehicle runs is not specified.

As the marker M for adding position information and the reader 4 for reading the marker, for example, a marker M in which position information (section information) is coded at each location where a road is divided into a plurality of sections is pre-printed on the road surface. When the vehicle passes over the marker M, the position information of the marker M can be read by the reader 4.

Specifically, for example, it is conceivable to provide a marker by a bar code and read the position information by a bar code reader.

Further, in the case of automatically traveling on a dedicated road while detecting a row of magnetic nails driven into the road surface by a magnetic sensor, a predetermined portion of the row of magnetic nails is used as a marker to operate the magnetic sensor. As a reader, the encoded position information can be read.

In this case, as shown in FIG. 2, a row of magnetic nails X are driven at regular intervals on the road surface of the automatic driving road ADR so that the N pole is directed upward so as to guide the traveling of the vehicle. A predetermined number of magnetic nails X1, X2, X3,... At each location where the dedicated road ADR is divided into a plurality of sections are coded by appropriately changing the polarities, so that that part is marked with a marker M for giving position information. Used as

Here, for example, a dedicated road ADR is set to 10
Are divided into sections B1 to B10, using five magnetic nails X1 to X5 at the beginning of each section, the first magnetic nail X1 is used as a position information flag so that the upper part becomes an S pole, By changing the polarities of the four magnetic nails X2 to X5 that follow, the binary coded position information is represented. That is, X2
Is set to the S pole "1", and X3 to X5 are all set to the N pole "0", thereby expressing the section B1. Also, by setting X2 to the N pole “0”, X3 to the S pole “1”, and X4 and X5 to the N pole “0”, the section B2 is expressed.
Section B3 is represented by setting both 2 and X3 to S pole "1" and setting both X4 and X5 to N pole "0". Hereinafter, the same applies.

When the amount of information is relatively small as described above, the position on the dedicated road ADR is not directly added, and the relation between each section number and the position of the dedicated road ADR is previously set in the arithmetic control unit 5 in a table. Then, the position on the dedicated road ADR corresponding to the read section number may be obtained.

As another means for adding position information and reading the position information, a transmission device for adding position information such as a beacon or a signpost is provided at an appropriate place on a road, and a vehicle-mounted receiver is provided when passing through the transmission device. , The location information transmitted from the transmission facility may be received.

An appropriate inter-vehicle distance is determined from the inter-vehicle distance and the relative speed between the host vehicle and the preceding vehicle, and the control target amount of the speed at which the vehicle follows the preceding vehicle while traveling while maintaining the appropriate inter-vehicle distance is changed. Conventional methods are widely applied as a method for outputting the same.

Further, when the vehicle automatically travels on a dedicated road provided with facilities for automatic traveling, if data of an inter-vehicle distance in accordance with a traveling speed instruction is transmitted from a roadside transmitter, the instruction is not transmitted. The control target amount of the speed that maintains the inter-vehicle distance according to the running speed is calculated.

With the above-described structure, when a position on the road is determined based on the traveling distance of the vehicle, the occurrence of a position error due to a change in tire diameter or meandering due to air pressure cannot be denied. Further, the occurrence of a position error due to a missing count of the number of magnetic nails cannot be denied. Therefore, the position error causes a decrease in accuracy of vehicle speed control for following the preceding vehicle while maintaining an appropriate inter-vehicle distance.

Therefore, according to the present invention, when the vehicle travels, every time the vehicle passes a marker M portion provided with position information locally provided on the road, the actual position on the road is obtained from the position information read by the reader 4. Knowing that, the position of the vehicle that has been detected independently is corrected.

However, at this time, the reading state of the marker M of the reader 4 attached to the vehicle body may be deteriorated due to pitching or rolling of the vehicle body accompanying the vehicle running, and the position information by the marker M may be deteriorated. An error in reading the contents may occur.

Alternatively, when receiving position information transmitted from a transmission facility such as a beacon, the reception state may be deteriorated due to noise, and a reading error of the content of the position information may occur.

However, if an error occurs in reading the content of the position information, the position of the self-vehicle detected independently is erroneously corrected, and the self-vehicle is made to follow the preceding vehicle while maintaining an appropriate inter-vehicle distance. Vehicle speed control will deviate.

For this reason, in the present invention, in particular, in the arithmetic and control unit 5, the validity of the order of the obtained position information is determined, and only when it is determined to be valid, the position at that time is determined. The position of the own vehicle is corrected using the information.

More specifically, when the position information is a section number coded by a row of magnetic nails, the section number obtained during traveling of the previous section and stored in the internal memory and the section number obtained this time The validity of the position information is determined by comparing whether or not the currently obtained section number is advanced.

Further, the validity condition may be strict, and the validity of the position information may be determined based on whether or not the vehicle advances by one section. In this case, if the position has advanced by one section, the position information obtained this time is determined to be valid, and the position correction is executed. Further, for example, if the vehicle has advanced by two sections or returned to the original position by one section, it is determined that the position information obtained this time is not appropriate, and the position is not corrected this time.

FIG. 3 shows a flow of processing in the arithmetic control unit 5 at that time.

For example, when the position information transmitted from the beacon directly indicates a position on the road, the position information of the beacon installed on the road dedicated to automatic driving is included in the position information. When the information of the order according to the order is entered, and the position information obtained last time is compared with the position information obtained this time, and the position information obtained this time is advanced by one. Then, it is determined that the position information obtained this time is appropriate.

As described above, according to the present invention, by judging the validity of the order of the position information obtained when passing through the position of each position information providing means installed on the road, the position information It is possible to determine whether or not the contents have been correctly read without errors. Therefore, when an error occurs in reading the position information, the correction of the position of the own vehicle is postponed in advance, and the correction of the position of the own vehicle is erroneously performed, and the vehicle follows the preceding vehicle while maintaining an appropriate inter-vehicle distance. It is possible to reliably prevent the occurrence of a situation in which the vehicle speed control for causing the vehicle speed to deviate.

Further, in the present invention, when the marker M and the reader 4 are used as means for adding and reading position information, in order to read the position information more accurately, as shown in FIG. Before and after the leader 41,
42, the same marker M is used when the vehicle 8 travels.
Is read by the two readers 41 and 42, respectively.

Then, the arithmetic and control unit 5 compares the contents of the position information read by the two readers 41 and 42 and determines whether or not the two match.

At this time, if they match, it is determined whether or not to correct the position after checking the validity of the order of the position information.

If they do not match at that time, the validity of the order of the read position information is determined, and the position is corrected based on any valid position information. .

The contents of the position information read by the two readers 41 and 42 are compared, and if they match, it is considered that no reading error has occurred, and the position is determined in accordance with the position information. Correction may be performed, and if they do not match, it may be considered that a reading error has occurred and position correction may not be performed.

[0039]

As described above, the present invention relates to an autonomous vehicle that automatically travels while recognizing the position of the vehicle on the road on which the vehicle is traveling on its own, and recognizes the position of the vehicle on the road. When obtaining the position information on the road and correcting the position of the own vehicle when passing through the location of the position information adding means locally installed in the vehicle, each position information on the road to be automatically driven Is included in advance, and the validity of the order of the position information obtained at the time of passing through the position information providing means is determined as to whether it is appropriate, and only when it is determined that the position information is valid, based on the position information, Since the position of the own vehicle is corrected by using this method, there is an advantage that an erroneous position correction due to an error in reading the position information can be reliably prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of an automatic traveling vehicle according to the present invention.

FIG. 2 is a diagram illustrating an example of a state in which a part of a row of magnetic nails for driving guidance driven into a road dedicated to automatic driving is used as a marker for adding position information.

FIG. 3 is a diagram illustrating an example of a processing flow when determining whether or not the order of the position information obtained from the position information providing unit is appropriate and correcting the position of the own vehicle.

FIG. 4 is a simplified diagram showing a state in which two readers are installed before and after a vehicle and the same marker is read twice.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Position detection part 2 Speed detection part 3 Communication part 4 Reader 5 Calculation control part 6 Accelerator drive part 7 Brake drive part 8 Vehicle 41 Reader 42 Reader M Marker

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G05D 1/02 G05D 1/02 R G09B 29/10 G09B 29/10 A

Claims (8)

[Claims] An autonomous vehicle that automatically determines a position on a road on which the own vehicle is running and recognizes the position of the own vehicle on the road, and is located locally on the road. Means for obtaining position information on the road when passing through the location of the information adding means, means for judging the validity of the order of the obtained position information, and position information determined to be valid And means for correcting the position of the own vehicle based on the self-driving vehicle. 2. The method according to claim 1, wherein the position information is road section information, and the section information obtained last time is compared with the section information obtained this time. 2. The self-driving vehicle according to claim 1, wherein the determined position information is determined to be valid. 3. The method according to claim 2, wherein when the currently obtained section information is advanced by one section, the currently obtained position information is determined to be valid. Traveling car. 4. Position information of the installation order of the corresponding position information providing means is put in the position information, and the order of the position information obtained last time is compared with the order of the position information obtained this time.
2. The self-driving vehicle according to claim 1, wherein the position information obtained this time is determined to be valid when the position information obtained this time is advanced. 5. The method according to claim 4, wherein when the position information obtained this time is advanced by one, the position information obtained this time is determined to be valid. Self-driving car. 6. The method according to claim 1, wherein the position information providing means is a marker provided on a road, and a reader provided on a vehicle reads the coded position information of the marker. Self-driving car according to the description. 7. The method according to claim 1, wherein the position information providing means is a row of magnetic nails buried on the road, and the magnetic sensor provided in the vehicle reads the coded position information of the row of magnetic nails. 2. The self-driving vehicle according to claim 1, wherein: 8. The method according to claim 1, wherein the location information providing means is a transmission facility installed on a road, and the location information transmitted from the transmission facility is received by a receiver provided in the vehicle. An autonomous vehicle according to claim 1.