JP6658022B2 - Own vehicle position detecting device, own vehicle position detecting method - Google Patents

Description

  The present invention relates to a technology for detecting a current position of a host vehicle by using a positioning result based on a positioning signal and outputs of a vehicle speed sensor and a direction sensor in combination.

  2. Description of the Related Art There has been proposed a technology for detecting a current position and a moving direction of a host vehicle on a map and utilizing the detected position and moving direction for various driving supports. For example, technologies have been developed for presenting a driver with directions to a destination and for automatically decelerating just before a curve. In such a technique, it is important to accurately detect the current position and the moving direction of the vehicle.

As a technology for detecting the current position and the moving direction of the own vehicle, a technology for detecting the current position, the moving speed, and the moving direction of the own vehicle by receiving a positioning signal from a positioning satellite is known. The technology contains large errors. Therefore, a vehicle speed sensor and a gyro sensor are mounted on the own vehicle, and the data of the traveling speed and azimuth change obtained from these sensors (hereinafter, onboard sensor) are also used to detect the current position of the own vehicle. Techniques for improving accuracy are used.
In the following, the traveling speed and the direction change amount obtained from the vehicle speed sensor and the gyro sensor are referred to as “relative information”, and the current position, the moving speed, and the moving direction obtained from the positioning signal are referred to as “absolute information”. There is. This is for the following reasons. The azimuth change amount obtained from the gyro sensor is not absolute information of the azimuth, but is relative information indicating a change amount from a certain azimuth. The traveling speed data obtained from the vehicle speed sensor can also be considered as relative information because it is data indicating the amount of movement over a certain period of time. On the other hand, the current position, moving speed, and moving direction obtained by receiving the positioning signal should be considered as absolute information indicating the current position, moving speed, and moving direction of the own vehicle at that time. This is because

If the absolute information based on the positioning signal and the relative information based on the vehicle speed sensor and the gyro sensor are used together, the current position, the moving speed, and the moving direction of the own vehicle can be obtained with high accuracy as follows. First, the sensor characteristics of the vehicle speed sensor and the gyro sensor are corrected by comparing the data of the moving speed and the moving direction obtained as the absolute information with the data of the traveling speed and the direction change amount obtained as the relative information. Furthermore, the traveling locus of the own vehicle is generated by accumulating the traveling speed and the azimuth change amount obtained as relative information, and the current position and the moving direction of the own vehicle are accurately determined by performing the map matching for collating with the map data. decide. If the sensor characteristics of the vehicle speed sensor and gyro sensor can be corrected in this way and the current position and moving direction can be determined accurately, the traveling speed and azimuth change amount obtained as relative information can be accumulated to obtain the current position of the vehicle. In addition, the moving speed and the moving direction can be accurately determined.
In addition, when the relative information is accumulated, the error included in the relative information is also accumulated, so that the detection accuracy decreases as the vehicle travels. For this reason, while the host vehicle is running, the process of correcting the sensor characteristics using both the absolute information and the relative information and the process of performing map matching are continuously executed.

However, if a tire slips or locks while the own vehicle is running, the output of the vehicle speed sensor outputs a value different from the actual behavior of the vehicle, so that the current position of the own vehicle is erroneously detected. In addition, because the output of the vehicle speed sensor is an abnormal value, the sensor characteristics are erroneously corrected, and as a result, the current position etc. is erroneously detected even after the tire slip or lock is cured. Is continued.
Therefore, when tire slip or lock occurs, instead of using the absolute information and the relative information together, various information is obtained using the current position, the moving speed, and the moving distance of the own vehicle obtained as the absolute information. (Patent Literature 1).

JP 2009-198185 A

  However, the proposed technology has a problem that the process of detecting the current position of the host vehicle or the like becomes complicated. That is, in the proposed technology, while no tire slip or lock occurs, the absolute information obtained from the positioning signal and the relative information obtained from the vehicle speed sensor and the gyro sensor are used together to automatically The current position of the vehicle is determined. When the slip or lock of the tire is detected, the process is switched to the process using the current position and the like obtained as the absolute information without using the relative information. Thereafter, when the tire slip or the lock is no longer detected, the process returns to the process of determining the current position of the host vehicle using the absolute information and the relative information again. As described above, it is necessary to switch between two different processes in a short time, so that the process becomes complicated. Further, a situation may occur where the current position of the own vehicle becomes discontinuous before and after the switching of the processing, and the processing may be further complicated if measures against the situation are taken into consideration.

  The present invention has been made in view of the above-described problems of the related art, and can easily detect the current position of the host vehicle with simple processing even when a tire slips or locks. The purpose is to provide a simple technology.

In order to solve the above-described problems, an own-vehicle position detecting device and an own-vehicle position detecting method according to the present invention compare a traveling locus of the own vehicle with a road shape read from map information to thereby determine a current position of the own vehicle. To determine. The running trajectory of the own vehicle is calculated based on the running speed obtained based on the output of the vehicle speed sensor and the running direction obtained based on the output of the direction sensor when no slip or lock occurs on the tire of the own vehicle. Is generated by accumulating. On the other hand, during the occurrence of slip or lock, it is generated by accumulating the moving speed and the moving direction of the own vehicle calculated based on the positioning signal. Further, in order to increase the accuracy of determining the current position of the vehicle, the sensor characteristics of the vehicle speed sensor are corrected by comparing the traveling speed obtained as a result of the positioning with the traveling speed obtained from the vehicle speed sensor. However, if the sensor characteristics are corrected during the occurrence of slip or lock, the accuracy of determining the current position of the host vehicle may be worsened. Therefore, if the occurrence of slip or lock is detected during the correction of the sensor characteristics, the correction of the sensor characteristics is performed by using the moving speed obtained as a positioning result instead of the traveling speed obtained by the vehicle speed sensor. To continue. As a result, instead of comparing the traveling speed with the traveling speed, the compensation of the sensor characteristics is continued formally by comparing the traveling speed with the traveling speed (ie, the same value). Thereafter, when the occurrence of slip or lock is no longer detected, the use of the traveling speed as a substitute for the traveling speed is terminated, and the use of the traveling speed is returned to the sensor characteristic by comparing the traveling speed with the traveling speed. It returns to the correction of.

In this way, when a slip or lock occurs in the tire of the own vehicle, a running locus can be generated without using the output of the vehicle speed sensor or the direction sensor, and the current position can be determined. Can be prevented from deteriorating the detection accuracy due to the influence of.
In addition, although the data used to generate the traveling locus of the own vehicle differs depending on the occurrence of slip or lock, the process of determining the current position by comparing the traveling locus with the road shape does not change. Also, it is possible to avoid complicated processing.
In addition, while tire slip and lock are not occurring, the vehicle speed sensor characteristics are corrected by comparing the traveling speed based on the positioning result with the vehicle speed sensor traveling speed. when the lock occurs by Rukoto using the moving speed of the positioning result, instead of running speed by the vehicle speed sensor, to correct the sensor characteristics. In this way, during the occurrence of a slip or a lock, the characteristic of the vehicle speed sensor is corrected by comparing the moving speed based on the positioning result with the moving speed based on the positioning result (ie, comparing the same value). Formally, the correction of the sensor characteristics can be substantially interrupted while the correction of the sensor characteristics is continued . For this reason, while no slip or lock occurs, the accuracy of determining the current position of the host vehicle can be improved by correcting the characteristics of the vehicle speed sensor. Since the correction is substantially interrupted, there is no possibility that the sensor characteristics are erroneously corrected to lower the accuracy. In addition, formally, the process of correcting the sensor characteristics itself is continuously executed, so the occurrence of slip or lock is detected and the correction process is interrupted, or the recovery from slip or lock is detected. There is no need to restart the correction process. For this reason, it is possible to avoid complicating the process of correcting the sensor characteristics.

FIG. 1 is an explanatory diagram showing a vehicle 1 on which a host vehicle position detection device 100 is mounted. FIG. 2 is a block diagram illustrating an internal configuration of the host vehicle position detection device. FIG. 3 is an explanatory diagram showing a situation in which the host vehicle position detection device 100 detects a current position by map matching. FIG. 4 is an explanatory diagram showing a state in which an erroneous traveling locus is generated when tire slip or lock occurs. It is a flowchart which shows the first half part of the own vehicle position detection processing. It is a flowchart which shows the latter half part of the own vehicle position detection processing. FIG. 9 is an explanatory diagram showing a state in which data used for correcting sensor characteristics is switched depending on whether or not a tire slip or lock occurs. FIG. 7 is an explanatory diagram showing a state in which data used for generating a traveling locus is switched depending on whether or not a tire slip or a lock has occurred. FIG. 2 is an explanatory diagram illustrating a traveling locus generated by a host vehicle position detection device; It is a block diagram showing the internal configuration of self-vehicle position detection device 100 of a modification. FIG. 10 is an explanatory diagram showing a state in which a vehicle position detection device 100 of a modified example determines reliability with respect to a current position.

Hereinafter, embodiments will be described in order to clarify the contents of the present invention described above.
A. Device configuration :
FIG. 1 shows a rough configuration of a vehicle 1 on which the own vehicle position detecting device 100 is mounted. As shown in the figure, a vehicle 1 includes a vehicle speed sensor 10 for detecting a traveling speed of the vehicle 1, an azimuth sensor 12 for detecting a traveling direction of the vehicle 1, and a positioning satellite 50 in addition to a vehicle position detecting device 100. A positioning signal receiving device 20 that receives a positioning signal from the vehicle, a driving support device 200 that supports a driver's driving operation, and the like are mounted. Note that the vehicle 1 of the present embodiment corresponds to the “own vehicle” of the present invention.

The vehicle speed sensor 10 outputs a certain number of pulses each time the tires of the vehicle 1 rotate, and it is possible to obtain information on the traveling speed of the vehicle 1 by counting the number of pulses output within a certain time. it can. Also, by counting the number of pulses from a certain point in time, the traveling distance of the vehicle 1 from that point can be obtained.
The direction sensor 12 is a so-called gyro sensor, and outputs a value corresponding to the direction change speed in the direction in which the vehicle 1 travels. By accumulating the output of the azimuth sensor 12, it is possible to obtain the azimuth change amount. Therefore, by accumulating the output of the azimuth sensor 12 from the time when the azimuth is known, the traveling direction of the vehicle 1 can be obtained. it can. The azimuth sensor 12 is not limited to a gyro sensor, but may be a terrestrial magnetism sensor that detects terrestrial magnetism to detect the azimuth.

The positioning signal receiving device 20 receives the positioning signals from the plurality of positioning satellites 50 to calculate the position where the vehicle 1 is present (hereinafter, “existing position”), the moving speed and the moving direction of the vehicle 1, and These are output as positioning results. It should be noted that the presence position obtained as a positioning result can also acquire altitude (height position) information in addition to so-called latitude and longitude information.
The own vehicle position detecting device 100 determines the current position of the vehicle 1 and the like based on the positioning result from the positioning signal receiving device 20 in addition to the output of the vehicle speed sensor 10 and the direction sensor 12.
The driving support device 200 receives the current position of the vehicle 1 from the own vehicle position detection device 100 and performs driving support such as route guidance to a destination.

FIG. 2 shows an internal configuration of the host vehicle position detection device 100. As shown in the figure, the vehicle position detection device 100 includes a traveling speed acquisition unit 101, a traveling direction acquisition unit 102, a positioning result acquisition unit 103, an occurrence detection unit 104, a sensor characteristic correction unit 105, and a traveling trajectory generation. A unit 106, a current position determination unit 107, a road shape reading unit 108, and a map information storage unit 109 are provided.
Note that these “parts” are abstractions that classify the inside of the host vehicle position detecting device 100 for convenience, focusing on functions provided for the host vehicle position detecting device 100 to detect the current position of the vehicle 1. It is a concept. Therefore, this does not indicate that the host vehicle position detection device 100 is physically divided into these “parts”. These “units” can be realized as a computer program executed by a CPU, as an electronic circuit including an LSI or a memory, or further, by combining these. .

The traveling speed acquisition unit 101 detects the traveling speed of the vehicle 1 based on the output from the vehicle speed sensor 10. As described above, the vehicle speed sensor 10 outputs a pulse corresponding to the number of rotations of the tire. Therefore, if the number of pulses within a certain time is counted and multiplied by a proportional coefficient (hereinafter referred to as a vehicle speed proportional coefficient), 1 can be calculated.
Since the magnitude of the vehicle speed proportional coefficient corresponds to the traveling distance of the vehicle 1 due to the rotation of the tire, the magnitude varies depending on the size of the tire. Furthermore, it changes depending on the wear of the tire due to running and the air pressure of the tire. Therefore, in order to accurately calculate the traveling speed of the vehicle 1, it is important to set the vehicle speed proportional coefficient to an appropriate value.

The traveling direction acquisition unit 102 receives the output from the direction sensor 12 and detects the traveling direction of the vehicle 1. In this embodiment, a gyro sensor is employed as the azimuth sensor 12, and the azimuth change speed can be obtained by multiplying the output of the gyro sensor by a proportional coefficient (hereinafter, azimuth proportional coefficient). Therefore, the running direction of the vehicle 1 can be obtained by accumulating a value obtained by multiplying the output of the gyro sensor by the azimuth proportional coefficient with reference to a point in time when the running direction of the vehicle 1 is known in advance. As the reference traveling direction, for example, the traveling direction of the vehicle 1 is stored when the power supply of the vehicle position detection device 100 is turned off, and the traveling direction can be read and used. Alternatively, the traveling direction of the vehicle 1 can be detected from the positioning result using the positioning signal from the positioning satellite 50 and used as the initial azimuth.
In addition, it is important to set the azimuth proportionality coefficient to an appropriate value in order to obtain an accurate traveling direction also for the traveling direction of the vehicle 1.

  The positioning result acquisition unit 103 acquires the positioning result (that is, the location p, the moving speed v, and the moving direction d of the vehicle 1) from the positioning signal receiving device 20. The movement speed v and the movement direction d are output to the occurrence detection unit 104 and the sensor characteristic correction unit 105. The position p is output to the road shape reading unit 108.

The occurrence detection unit 104 detects the vehicle 1 based on the traveling speed from the traveling speed acquisition unit 101, the traveling direction from the traveling direction acquisition unit 102, and the traveling speed v and the traveling direction d from the positioning result acquisition unit 103. Detects the occurrence of slip or lock on tires.
The occurrence or non-occurrence of tire slip or lock can be determined as follows.
For example, when there is a speed difference greater than or equal to a threshold value between the traveling speed acquired from the traveling speed acquisition unit 101 and the traveling speed v acquired from the positioning result acquisition unit 103, it is determined that tire slip or lock has occurred. can do.
Alternatively, when there is a change speed difference greater than or equal to a threshold value between the azimuth change speed indicated by the traveling direction acquisition unit 102 and the azimuth change speed calculated based on the movement direction d from the positioning result acquisition unit 103, the slip of the tire is determined. And that lock has occurred.
Further, when the output of the vehicle speed sensor 10 or the output of the azimuth sensor 12 changes suddenly, that is, when the amount of change with respect to the previously obtained output is equal to or more than a predetermined value, it is determined that tire slip or lock has occurred. can do.

When the occurrence detecting unit 104 determines that the tire slip or the lock has not occurred, the occurrence detecting unit 104 detects the traveling speed acquired from the traveling speed acquiring unit 101 and the traveling direction acquired from the traveling direction acquiring unit 102 by a sensor. Output to the characteristic correction unit 105 and the traveling locus generation unit 106.
On the other hand, when it is determined that the tire has slipped or locked, the moving speed v and the moving direction d acquired from the positioning result acquiring unit 103 are transmitted to the sensor characteristic correcting unit 105 and the traveling locus generating unit 106. Output.

The sensor characteristic correction unit 105 receives the traveling speed from the traveling speed acquisition unit 101 and the traveling direction from the traveling direction acquisition unit 102 via the generation detection unit 104, and also receives the traveling speed v and the movement from the positioning result acquisition unit 103. The direction d has been received. Then, the sensor characteristics of the vehicle speed sensor 10 are corrected by comparing the traveling speed from the traveling speed acquisition unit 101 with the traveling speed v from the positioning result acquisition unit 103.
That is, the traveling speed from the traveling speed acquisition unit 101 is calculated by multiplying the pulse number of the vehicle speed sensor 10 by the vehicle speed proportional coefficient. If the vehicle speed proportional coefficient is small, the obtained traveling speed is a small value, and if the vehicle speed proportional coefficient is large, the traveling speed is a large value. Therefore, the traveling speed obtained by multiplying the number of pulses of the vehicle speed sensor 10 by the vehicle speed proportional coefficient is compared with the moving speed v obtained from the positioning result acquisition unit 103 to correct the vehicle speed proportional coefficient. Can be. For example, as a result of comparing the traveling speed and the traveling speed v over a plurality of times, if the traveling speed seems to be smaller as a whole, it can be determined that the vehicle speed proportional coefficient is smaller. Correct the proportionality coefficient to be larger. Conversely, if the running speed is higher as a whole, it can be determined that the vehicle speed proportional coefficient is large, so the vehicle speed proportional coefficient is corrected to be small. The sensor characteristic correction unit 105 corrects the sensor characteristics of the vehicle speed sensor 10 in this way.

In addition, the sensor characteristic correction unit 105, based on the traveling direction received from the traveling direction acquisition unit 102 via the occurrence detection unit 104 and the traveling direction received from the positioning result acquisition unit 103, as follows: The sensor characteristics of the direction sensor 12 are corrected.
First, the amount of change per time (that is, the azimuth change speed) is calculated based on the traveling direction acquired from the traveling direction acquisition unit 102. The azimuth change speed corresponds to the azimuth change speed obtained by multiplying the output of the azimuth sensor 12 (here, a gyro sensor) by the azimuth proportional coefficient by the traveling direction acquisition unit 102. If the azimuth proportional coefficient is small, the obtained azimuth traveling speed is a small value, and if the azimuth proportional coefficient is large, the azimuth traveling speed is a large value. Therefore, by comparing the azimuth change speed obtained based on the travel direction from the travel direction acquisition unit 102 with the change speed in the travel direction d obtained based on the travel direction from the positioning result acquisition unit 103, The direction proportional coefficient can be corrected. For example, if the azimuth traveling speed and the change speed of the moving direction d are compared a plurality of times, and the overall azimuth traveling speed is smaller, the azimuth proportionality used in the calculation of the azimuth traveling speed is obtained. Since it can be determined that the coefficient is small, the azimuth proportional coefficient is corrected to be large. Conversely, if the azimuth traveling speed is higher as a whole, it can be determined that the azimuth proportional coefficient is larger, and the azimuth proportional coefficient is corrected to be smaller. The sensor characteristic correction unit 105 also corrects the sensor characteristics of the direction sensor 12 in this way.

Then, the sensor characteristic correction unit 105 outputs the obtained correction result of the sensor characteristic to the traveling speed acquisition unit 101 and the traveling direction acquisition unit 102. As a result, thereafter, the traveling speed acquisition unit 101 and the traveling direction acquisition unit 102 acquire the traveling speed and the traveling direction using the corrected sensor characteristics.
As described above, the occurrence detection unit 104 detects the traveling speed from the traveling speed acquisition unit 101 and the traveling direction from the traveling direction acquisition unit 102 while the tire slip or lock does not occur, as described above. Output to 105. However, when the tire slips or locks, the movement speed v and the movement direction d from the positioning result acquisition unit 103 are output to the sensor characteristic correction unit 105. The reason will be described later in detail.

The traveling locus generating unit 106 detects the traveling speed acquired by the traveling speed acquiring unit 101 and the traveling direction acquired by the traveling direction acquiring unit 102 while the tire slip and the lock are not occurring, and outputs the traveling detection acquired by the occurrence detecting unit 104. To get through. Further, while the tire is slipping or locking, the moving speed and the moving direction acquired by the positioning result acquiring unit 103 are acquired via the occurrence detecting unit 104.
Then, the traveling locus of the vehicle 1 is generated by accumulating these data acquired from the occurrence detecting unit 104 and output to the current position determining unit 107.

The current position determination unit 107 determines the current position of the vehicle 1 by executing a so-called map matching based on the traveling locus received from the traveling locus generating unit 106 and the road shape received from the road shape reading unit 108. I do.
When receiving the current location of the vehicle 1 from the positioning result acquisition unit 103, the road shape reading unit 108 refers to the map information stored in the map information storage unit 109 and determines a predetermined location around the location of the vehicle 1. The road shape within the range is read and output to the current position determination unit 107.

FIG. 3 illustrates an example in which the current position determination unit 107 determines the current position of the vehicle 1 by performing map matching. If the traveling speed and traveling direction of the vehicle 1 are accumulated, the traveling locus of the vehicle 1 can be obtained as illustrated in FIG. The current position determining unit 107 acquires such a running locus from the running locus generation unit 106.
In addition, since the vehicle 1 normally travels on a road, the traveling locus of the vehicle 1 may be considered to match the road shape. Therefore, the location position p of the vehicle 1 obtained by the positioning result obtaining unit 103 is obtained, and the surrounding road shape including the location is obtained. Then, a position where the traveling locus of the vehicle 1 matches the road shape is searched. In this way, the accurate current position of the vehicle 1 can be determined as illustrated in FIG. At this time, it is also possible to determine an accurate traveling direction of the vehicle 1.
The current position determination unit 107 of the host vehicle position detection device 100 determines the accurate current position (and the traveling direction) of the vehicle 1 in this way, and outputs the current position to the driving support device 200.

Here, if tire slip or lock occurs while the vehicle 1 is traveling, the traveling speed obtained by the traveling speed acquisition unit 101 becomes a value significantly different from the actual value. Similarly, when the tire slips or locks, the running direction obtained by the running direction acquisition unit 102 is significantly different from the actual value.
As a result, for example, when a tire slip occurs, the traveling locus obtained by accumulating the traveling speed from the traveling speed acquisition unit 101 and the traveling direction from the traveling direction acquisition unit 102 is indicated by a black arrow in FIG. As illustrated, the trajectory is significantly different from the actual traveling trajectory. Similarly, when the tire is locked, the obtained traveling locus is significantly different from the actual traveling locus as exemplified by the black arrow in FIG. 4B.
Therefore, if map matching is performed based on such an erroneous traveling locus, the current position of the vehicle 1 is erroneously determined.

  Also, when correcting the sensor characteristics of the vehicle speed sensor 10 and the azimuth sensor 12 using a value that is significantly different from the actual value, the sensor characteristics will be greatly erroneously corrected. If the sensor characteristics are corrected incorrectly, it will not be possible to obtain the correct running speed and running direction after that, so it will not be possible to generate an accurate running locus, and the correct current position will be determined. You can't do that. Such a state is continued until the sensor characteristics are corrected to correct characteristics.

Of course, when tire slip or lock occurs, such a problem can be avoided if the generation of the traveling locus and the correction of the sensor characteristics are not performed. In addition, the location p, the moving speed v, and the moving direction d of the vehicle 1 acquired by the positioning result acquiring unit 103 may be directly output to the driving support device 200.
However, in this case, the own vehicle position detecting device 100 performs completely different processing depending on whether tire slip or lock has occurred or not, and therefore the own vehicle position detecting device 100 Becomes complicated. Further, since two processes having completely different processing contents are switched, it is difficult to maintain the continuity of the output contents.
Therefore, the own vehicle position detecting device 100 of the present embodiment detects the current position of the vehicle 1 as follows.

B. Own vehicle position detection processing:
5 and 6 show flowcharts of the host vehicle position detection processing executed by the host vehicle position detection device 100.
As shown in the figure, in the own vehicle position detecting process, first, the current position p, the moving speed v, and the moving direction d of the vehicle 1 are obtained by using the positioning result obtaining unit 103 (S100). These pieces of information (that is, the existing position p, the moving speed v, and the moving direction d) are calculated by the positioning signal receiving device 20 as a positioning result based on the positioning signal, and the positioning result obtaining unit 103 outputs the positioning signal receiving device 20 Obtain the positioning result calculated by.

Subsequently, the traveling speed of the vehicle 1 is acquired using the traveling speed acquisition unit 101 (S101). The traveling speed acquisition unit 101 calculates the traveling speed of the vehicle 1 from the output of the vehicle speed sensor 10 in consideration of the sensor characteristics of the vehicle speed sensor 10 (that is, the vehicle speed proportional coefficient).
The traveling direction of the vehicle 1 is acquired by using the traveling direction acquisition unit 102 (S102). The traveling direction acquisition unit 102 calculates the traveling direction of the vehicle 1 from the output of the direction sensor 12 in consideration of the sensor characteristics of the direction sensor 12 (that is, the direction proportional coefficient).

  Then, using the occurrence detection unit 104, it is determined whether a slip or lock has occurred in the tires of the vehicle 1 (S103). As described above, the occurrence or non-occurrence of tire slip or lock is determined by the traveling speed calculated from the output of the vehicle speed sensor 10, the traveling direction calculated from the output of the bearing sensor 12, the traveling speed acquired from the positioning signal receiving device 20, and the like. The determination can be made based on the moving direction.

  As a result, if the tire has not slipped or locked (S103: no), the positioning signal receiving device 20 calculates the traveling speed based on the output of the vehicle speed sensor 10 and the traveling direction based on the output of the azimuth sensor 12. Using the determined moving speed v and moving direction d, the correction amount of the sensor characteristics of the vehicle speed sensor 10 and the direction sensor 12 is calculated (S104). That is, as described above with reference to FIG. 2, if the traveling speed based on the output of the vehicle speed sensor 10 and the traveling direction based on the output of the direction sensor 12 are supplied to the sensor characteristic correction unit 105, the traveling speed and the traveling direction are calculated. , The correction amount of the sensor characteristic can be calculated based on the moving speed v and the moving direction d.

  Further, the traveling locus of the vehicle 1 is generated by accumulating the traveling speed based on the output of the vehicle speed sensor 10 and the traveling direction based on the output of the direction sensor 12 (S105). That is, as described above with reference to FIG. 2, if the traveling speed based on the output of the vehicle speed sensor 10 and the traveling direction based on the output of the azimuth sensor 12 are supplied to the traveling locus generation unit 106, the traveling locus of the vehicle 1 is calculated. Can be generated.

On the other hand, if the tire has slipped or locked (S103: yes), the movement speed v and the movement direction d obtained by the positioning signal receiving device 20 are supplied to the sensor characteristic correction unit 105. Then, the correction amount of the sensor characteristic is calculated (S106). Further, the traveling locus of the vehicle 1 is generated by supplying the traveling speed v and the traveling direction d to the traveling locus generating unit 106 (S107).
As described above, in the own-vehicle position detection process of the present embodiment, the data supplied to the sensor characteristic correction unit 105 and the traveling trajectory generation unit 106 are switched according to the occurrence of slip or lock of the tire. This makes it possible to prevent the processing in the host vehicle position detection device 100 from becoming complicated for the following reasons.

FIG. 7 shows a state in which the occurrence detection unit 104 switches data to be supplied to the sensor characteristic correction unit 105 in accordance with the presence / absence of a slip or a lock of the tire.
For example, during normal times when tire slip or lock does not occur, as shown in FIG. 7A, the traveling speed obtained based on the output of the vehicle speed sensor 10 and the running speed obtained based on the output of the direction sensor 12 are obtained. The traveling direction is supplied to the sensor characteristic correction unit 105. The sensor characteristic correction unit 105 compares the traveling speed and the traveling direction supplied in this way with the traveling speed v and the traveling direction d separately supplied from the positioning result acquisition unit 103, thereby obtaining the vehicle speed sensor 10 and the azimuth sensor 12. The correction amount of the sensor characteristic can be calculated.

  On the other hand, when a tire slips or locks, as shown in FIG. 7B, instead of the traveling speed based on the output of the vehicle speed sensor 10 and the traveling direction based on the output of the azimuth sensor 12, positioning is performed. The moving speed v and the moving direction d obtained by the signal receiving device 20 are supplied to the sensor characteristic correction unit 105. Therefore, the sensor characteristic correction unit 105 compares the moving speed v and the moving direction d supplied from the occurrence detecting unit 104 with the moving speed v and the moving direction d supplied from the positioning result acquiring unit 103. . Since the same information is compared, the correction amount of the sensor characteristic calculated by the sensor characteristic correction unit 105 becomes “0”, and the correction of the sensor characteristic can be substantially interrupted.

As described above, the sensor characteristic correction unit 105 of the present embodiment compares the data supplied from the occurrence detection unit 104 and the data supplied from the positioning result acquisition unit 103 irrespective of whether or not a tire slip or lock has occurred. By performing the comparison, the correction amounts of the sensor characteristics of the vehicle speed sensor 10 and the direction sensor 12 are calculated. Therefore, in the sensor characteristic correction unit 105, there is no need to switch the processing content, so that the processing can be prevented from becoming complicated.
Nevertheless, the correction of the sensor characteristics can be substantially interrupted while the tire is slipping or locking, thereby avoiding a situation in which the sensor characteristics of the vehicle speed sensor 10 and the direction sensor 12 are erroneously corrected. be able to.

In the above, it has been described that the processing performed by the sensor characteristic correction unit 105 does not change the actual processing content irrespective of the occurrence of slip or lock of the tire. The same applies to the processing performed by the traveling locus generation unit 106.
FIG. 8 shows a state in which the occurrence detection unit 104 switches the data to be supplied to the traveling trajectory generation unit 106 in accordance with the presence / absence of occurrence of tire slip or lock. At normal times when tire slip or lock does not occur, as shown in FIG. 8A, the traveling speed obtained based on the output of the vehicle speed sensor 10 and the traveling obtained based on the output of the bearing sensor 12 The direction is supplied to the traveling locus generation unit 106. The running locus generating unit 106 generates a running locus of the vehicle 1 by accumulating the running speed and the running direction thus supplied.

  On the other hand, when the tire slips or locks, as shown in FIG. 8B, instead of the traveling speed based on the output of the vehicle speed sensor 10 and the traveling direction based on the output of the azimuth sensor 12, positioning is performed. The moving speed v and the moving direction d obtained by the signal receiving device 20 are supplied to the traveling locus generating unit 106. Therefore, when the tire slips or locks, the traveling locus generating unit 106 generates the traveling locus of the vehicle 1 by accumulating the moving speed v and the moving direction d.

In S104 to S107 of the own vehicle position detection processing shown in FIGS. 5 and 6, the correction amounts of the sensor characteristics of the vehicle speed sensor 10 and the azimuth sensor 12 are calculated as described above, and the traveling locus of the vehicle 1 is generated. I do.
Subsequently, the sensor characteristics of the vehicle speed sensor 10 and the azimuth sensor 12 are corrected using the correction amounts of the sensor characteristics obtained in S104 or S106 (S108 in FIG. 5). As a result, the traveling speed acquired in the next step S101 and the traveling direction acquired in the step S102 have values reflecting the corrected sensor characteristics.

Thereafter, the traveling locus generated in S105 or S107 is read (S109).
FIG. 9A illustrates the traveling locus read in this way. It is assumed that the vehicle 1 is traveling on the same route as the traveling locus illustrated in FIG.
In FIG. 9A, a running locus indicated by a white arrow indicates a running speed based on the output of the vehicle speed sensor 10 and a running direction based on the output of the direction sensor 12 in a normal state when tire slip or lock does not occur. Are accumulated (that is, the traveling locus generated in S105 of FIG. 5). On the other hand, the running locus indicated by the black arrow in FIG. 9A is a running locus obtained by accumulating the moving speed v and the moving direction d obtained by the positioning signal receiving device 20 (that is, FIG. 9A). 5 is the traveling locus generated in S107 of FIG.

FIG. 9B illustrates a traveling locus obtained by accumulating the traveling speed by the vehicle speed sensor 10 and the traveling direction by the direction sensor 12 even while the tire is slipping, for reference. . The running locus indicated by the hatched arrow in FIG. 9B is the running locus when the tire slips.
When the tire is slipping, the tire spins, so the running speed obtained based on the output of the vehicle speed sensor 10 becomes a value larger than the actual value. For this reason, if the running speed obtained by the vehicle speed sensor 10 and the running direction obtained by the direction sensor 12 are accumulated, the running locus greatly differs from the actual running locus.
As apparent from a comparison between the traveling locus shown in FIG. 9A and the traveling locus shown in FIG. 9B, the traveling locus shown in FIG. Of the vehicle 1).

Of course, the traveling locus illustrated in FIG. 9A does not exactly match the actual traveling locus of the vehicle 1. This is because the moving speed v and the moving direction d obtained by the positioning signal receiving device 20 are not so high in accuracy.
However, slip and lock on the tires occur only for a short period of time. Therefore, even if the traveling speed v and the traveling direction d obtained by the positioning signal receiving device 20 are accumulated instead of the traveling speed obtained by the vehicle speed sensor 10 and the traveling direction obtained by the direction sensor 12, The shape of the traveling trajectory does not change significantly.

After the traveling locus is read in this manner (S109 in FIG. 5), subsequently, a road shape in a predetermined range including the location p of the vehicle 1 is read from the map information storage unit 109 (S110 in FIG. 6).
After the current position and the traveling direction of the vehicle 1 are determined by performing map matching (S111), the determined current position and the traveling direction are output to the driving support device 200 (S112).
Thereafter, it is determined whether or not to end the own vehicle position detection processing (S113). If not (S113: no), the processing returns to the beginning of the processing and the positioning result is received from the positioning signal receiving device 20 (that is, the own vehicle). Is obtained (S100 in FIG. 5).
On the other hand, when ending the processing (S113: yes), the own vehicle position detection processing shown in FIGS. 5 and 6 is ended.

The host vehicle position detection device 100 of the present embodiment determines the current position of the vehicle 1 by performing the host vehicle position detection processing described above. At the time of the determination, the traveling locus of the vehicle 1 is generated and map matching is performed. However, even when a tire slips or locks, a traveling locus that is not much different from the actual traveling locus can be obtained. For this reason, it is possible to determine the current position of the vehicle 1 with high accuracy by performing map matching regardless of the occurrence of tire slip or lock.
Further, as described above with reference to FIG. 8, although the data accumulated for generating the traveling locus can be switched according to the occurrence or non-occurrence of the tire slip or lock, the process itself for generating the traveling locus is the same as the process. Has become. For this reason, there is no need to switch between different processing contents depending on whether or not a tire slip or lock has occurred, so that the processing does not become complicated.
In addition, since the same processing is continuously performed regardless of the occurrence of slip or lock of the tire, the result of the processing (here, the current position of the vehicle 1) is performed when slip or lock occurs or ends. ) Can be avoided.

In addition, when determining the current position of the vehicle 1, the host vehicle position detection device 100 of the present embodiment also corrects the sensor characteristics of the vehicle speed sensor 10 and the direction sensor 12. When a tire slips or locks, the output of the vehicle speed sensor 10 or the azimuth sensor 12 has an abnormal value. If the sensor characteristics are corrected using such an output, the sensor characteristics may be corrected erroneously. become.
However, as described above with reference to FIG. 7, the self-vehicle position detection device 100 of the present embodiment substantially stops the correction of the sensor characteristics when a tire slips or locks. There is no accidental correction.
In addition, although the data used for correcting the sensor characteristics is switched depending on whether or not the tire has slipped or locked, the processing for correcting the sensor characteristics is the same. For this reason, there is no need to switch between different processing contents depending on whether or not a tire slip or lock occurs, so that the processing does not become complicated.

C. Modifications:
The above-described own vehicle position detecting device 100 of the present embodiment has a modification. Hereinafter, this modified example will be briefly described focusing on differences from the present embodiment.

Generally, the positioning signal receiving device 20 can usually calculate information on the reliability of the positioning result in addition to the positioning result.
Further, when determining the correction amount to be added to the sensor characteristics of the vehicle speed sensor 10 and the direction sensor 12, the sensor characteristic correction unit 105 can obtain information on the reliability of the current position determined by the current position determination unit 107. This can be easily understood by considering the following.

For example, it is assumed that the sensor characteristics are greatly shifted. In this case, the correction amount of the sensor characteristics increases and an accurate traveling locus cannot be obtained, so that the reliability of the current position determined by the current position determination unit 107 decreases. It is also assumed that the positioning result obtained by the positioning signal receiving device 20 includes a large error. Also in this case, the correction amount of the sensor characteristics increases, and the reliability of the current position determined by the current position determination unit 107 decreases.
On the other hand, it is assumed that the sensor characteristics are set to appropriate values, and the positioning result obtained by the positioning signal receiving device 20 also has sufficient accuracy. In this case, the correction amount of the sensor characteristics becomes small, and the reliability of the current position determined by the current position determination unit 107 increases.
Thus, when the sensor characteristic correction unit 105 determines a correction amount to be added to the sensor characteristics of the vehicle speed sensor 10 and the azimuth sensor 12, information on reliability can be obtained.
Therefore, the reliability of the current position may be determined based on the information on the reliability obtained from the positioning signal receiving device 20 or the information on the reliability obtained by the sensor characteristic correction unit 105.

  FIG. 10 shows the internal configuration of the host vehicle position detection device 100 of such a modification. The own vehicle position detecting device 100 of the modified example shown in the drawing differs from the own vehicle position detecting device 100 of the present embodiment described above with reference to FIG. 2 in that the sensor characteristic correcting unit 105 and the positioning result obtaining unit 103 transmit the current position determining unit. The point that the information on the reliability is supplied to the current position determining unit 107 is greatly different from the point that the information indicating whether the slip or the lock of the tire is generated is supplied from the occurrence detecting unit 104 to the current position determining unit 107. ing. The other points are the same as in the above-described embodiment, and the description is omitted here.

The reliability information supplied from the sensor characteristic correction unit 105 to the current position determination unit 107 is obtained by the sensor characteristic correction unit 105 when the sensor characteristic correction unit 105 corrects the sensor characteristics as described above. Information. The reliability information supplied from the positioning result acquisition unit 103 to the current position determination unit 107 is information calculated by the positioning signal receiving device 20 together with the positioning result. In FIG. 10, the dashed arrow from the positioning result acquisition unit 103 to the current position determination unit 107 and the dashed arrow from the sensor characteristic correction unit 105 to the current position determination unit 107 indicate the reliability of the current position determination unit 107. Indicates that information is supplied.
A dashed-dotted arrow from the occurrence detection unit 104 to the current position determination unit 107 indicates that information on whether or not tire slip or lock has occurred is supplied from the occurrence detection unit 104 to the current position determination unit 107. I have.
Upon receiving these pieces of information, the current position determination unit 107 of the modification determines the reliability of the current position as follows.

FIG. 11 shows how the current position determination unit 107 of the modification determines the reliability of the current position.
First, if tire slip or lock has occurred, the reliability for the current position is determined to be “low” regardless of the reliability information obtained from the sensor characteristic correction unit 105 or the positioning result acquisition unit 103. . The reason for this is that when the tire slips or locks, the current position is substantially determined based solely on the positioning result of the positioning signal receiving device 20, so that sufficient accuracy cannot be ensured. .

If the tire has not slipped or locked, based on the reliability information obtained from the sensor characteristic correction unit 105 and the positioning result acquisition unit 103, the reliability of the current position is calculated as follows. decide.
If the reliability obtained from the sensor characteristic correction unit 105 and the reliability obtained from the positioning result acquisition unit 103 are both “low”, the reliability for the current position is determined to be “low”. Conversely, if both are “high”, the reliability for the current position is determined to be “high”. In other cases, that is, when one is “low” and the other is “high”, the reliability of the current position is determined to be “medium”.

  When outputting the current position to the driving support device 200, the current position determination unit 107 of the modification also outputs information on the reliability determined by the above-described method. For this reason, in the driving support device 200, when the reliability is low, the content of the driving support can be stopped sparingly, and when the reliability is high, the driving support can be actively performed. The burden can be greatly reduced.

  Although the present embodiment and the modified examples have been described above, the present invention is not limited to the above-described embodiment and modified examples, and can be implemented in various modes without departing from the gist of the present invention.

1 ... vehicle, 10 ... vehicle speed sensor, 12 ... direction sensor,
Reference numeral 20: positioning signal receiving device, 50: positioning satellite, 100: own vehicle position detecting device,
101: traveling speed acquisition unit 102: traveling direction acquisition unit 103: positioning result acquisition unit
104: an occurrence detection unit, 105: a sensor characteristic correction unit, 106: a traveling locus generation unit,
107: current position determination unit 108: road shape reading unit 109: map information storage unit
200: Driving support device.

Claims (2)

An own vehicle position detecting device (100) for detecting a current position of the own vehicle (1),
A positioning result acquisition unit (103) that is calculated based on a plurality of positioning signals and acquires a positioning result including at least the location of the host vehicle, the moving speed of the host vehicle, and the moving direction of the host vehicle. When,
A traveling speed acquisition unit (101) for acquiring a traveling speed of the own vehicle based on an output of a vehicle speed sensor (10) mounted on the own vehicle;
A sensor characteristic correction unit (105) that corrects a sensor characteristic of the vehicle speed sensor by comparing the moving speed obtained as the positioning result with the traveling speed obtained from the vehicle speed sensor;
A traveling direction acquisition unit (102) for acquiring a traveling direction of the own vehicle based on an output of a direction sensor (12) mounted on the own vehicle;
A traveling locus generating unit (106) that generates a traveling locus of the host vehicle by accumulating the traveling speed and the traveling direction;
A road shape reading unit (108) for reading, from map information in which the road shape is described, the road shape in a predetermined range including the location of the vehicle,
A current position determining unit (107) that determines the current position of the host vehicle by comparing the read road shape with the traveling locus of the host vehicle;
An occurrence detection unit (104) for detecting occurrence of slip or lock on the tire of the host vehicle,
The sensor characteristic correction unit,
If the occurrence of the slip or lock is detected during the correction of the sensor characteristics, instead of comparing the traveling speed with the traveling speed, the traveling speed and the traveling speed as a substitute for the traveling speed are used. By comparing, the correction of the sensor characteristics is continued,
When the occurrence of the slip or the lock is no longer detected, by returning the traveling speed used as a substitute for the traveling speed to the traveling speed, the sensor characteristic of the sensor by comparing the traveling speed with the traveling speed is reduced. Return to compensation,
When the occurrence of the slip or the lock is detected, the traveling trajectory generation unit accumulates the traveling speed and the traveling direction obtained as the positioning result, instead of the traveling speed and the traveling direction, thereby accumulating the traveling speed and the traveling direction. An own-vehicle position detecting device for generating a traveling locus. An own vehicle position detecting method for detecting a current position of the own vehicle (1),
Acquiring a positioning result calculated based on a plurality of positioning signals and including at least the location of the host vehicle, the moving speed of the host vehicle, and the moving direction of the host vehicle (S100);
A step (S101) of acquiring a running speed of the host vehicle based on an output of a vehicle speed sensor (10) mounted on the host vehicle;
A step (S102) of acquiring a traveling direction of the host vehicle based on an output of a direction sensor (12) mounted on the host vehicle;
Generating a traveling locus of the host vehicle by accumulating the traveling speed and the traveling direction (S105, S107);
Correcting the sensor characteristics of the vehicle speed sensor by comparing the traveling speed obtained as a result of the positioning with the traveling speed obtained from the vehicle speed sensor (S108);
Reading a road shape in a predetermined range including the location of the vehicle from map information describing the road shape (S110);
Determining the current position of the host vehicle by comparing the read road shape with the traveling locus of the host vehicle (S111);
Detecting the occurrence of slip or lock on the tires of the host vehicle (S103).
The step of correcting the sensor characteristics of the vehicle speed sensor,
If the occurrence of the slip or lock is detected during the correction of the sensor characteristics, instead of comparing the traveling speed with the traveling speed, the traveling speed and the traveling speed as a substitute for the traveling speed are used. By comparing, the correction of the sensor characteristics is continued ,
When the occurrence of the slip or the lock is no longer detected, by returning the traveling speed used as a substitute for the traveling speed to the traveling speed, the sensor characteristic of the sensor by comparing the traveling speed with the traveling speed is reduced. It is a process to return to the correction ,
The step of generating the traveling locus includes, when the occurrence of the slip or the lock is detected, accumulating the traveling speed and the traveling direction obtained as the positioning result instead of the traveling speed and the traveling direction. And generating the travel locus by performing the process.

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