JP4366660B2 - Correction coefficient calculation device and calculation program for direction sensor - Google Patents

Description

  The present invention relates to a correction coefficient calculation device and calculation program for calculating a correction coefficient for correcting output information from a direction sensor using a signal from a GPS satellite, and a self-position recognition device and a recognition program.

  Regarding a technique for correcting output information of an orientation sensor such as a gyroscope, for example, the following Patent Document 1 discloses a technique related to a vehicle current position detection device as described below. This vehicle current position detection device includes a gyro that outputs a signal corresponding to the rotational angular velocity of the vehicle, a distance sensor that outputs a pulse signal corresponding to the moving distance of the vehicle, and a radio wave transmitted from a GPS (Global Positioning System) satellite. GPS receiver that detects the position, heading (traveling direction), speed, etc. of the vehicle, and the dead reckoning navigation such as the current position and traveling direction of the vehicle based on the output from the gyro, distance sensor, GPS receiver A current position detecting unit for detecting data to be performed.

  The current position detecting unit includes a moving distance calculating unit that calculates a moving distance of the vehicle based on a pulse signal from a distance sensor, and an azimuth changing amount calculating unit that calculates an azimuth changing amount based on a detection signal from the gyro. And a relative trajectory calculation unit that calculates a relative trajectory and a vehicle speed based on the calculated azimuth change amount and moving distance, and an absolute azimuth and absolute position that are also calculated based on the azimuth change amount and moving distance. Various calculation parameters and calculation results used to calculate the vehicle speed, heading, and position, using the difference between the calculated value in the position calculation unit, relative trajectory calculation unit and absolute position calculation unit and the detected value in the GPS receiver as an observation value An error estimator composed of a Kalman filter that obtains an estimated value of the state quantity and an estimated value of the state quantity (that is, error) calculated by the error estimator, And a correcting unit for correcting the parameters and calculated values. Here, as one of the state quantities, a conversion gain error (gain error) from gyro output to angular velocity is estimated. Then, the azimuth change amount calculated using the gyro output and the conversion gain is corrected based on the gain error estimated value obtained by the error estimation unit.

  This vehicle current position detection device is capable of detecting the direction from the output of the gyro without complicating the configuration of the gyro even if the conversion gain of the gyro includes a gain error due to the aging of the gyro and the installation angle. The object is to make it possible to obtain the amount of change stably and accurately.

JP 2000-55678 A (page 4-5, FIG. 1)

  In the technique described in Patent Document 1, the process of calculating the error is repeated every time information is obtained from the GPS receiver, regardless of whether or not the direction of the vehicle is changed. There is an advantage that can be corrected at any time. However, with the Kalman filter, the difference between the calculated value in the relative trajectory calculating unit and the absolute position calculating unit and the detected value in the GPS receiver is used as an observed value, and the gyro gain error is estimated as one of the state quantities. Therefore, there is a problem that a high processing load is required due to a heavy calculation load on the calculation processing device.

  On the other hand, the difference between the output from the gyro and the detected value at the GPS receiver becomes significant when the orientation is changed at a relatively large angle. Therefore, for such a case where the azimuth change is performed, the azimuth change calculated based on the information from the gyro and the azimuth change calculated based on the information from the GPS receiver are compared. If the error is calculated to correct the output information of the gyro, the calculation load on the calculation processing device can be reduced. By the way, in this method, it is difficult to accurately correct the error of the output information of the gyro unless the state of the azimuth change is appropriately determined and the information on the two azimuth change amounts to be compared is not acquired. . However, until now, including the conditions for obtaining the azimuth change based on the information from the GPS receiver and the azimuth change based on the information from the gyro, the error in the output information of the gyro is appropriately corrected. The technology for this was not established.

  The present invention has been made in view of the above-described problems, and the purpose of the present invention is to provide information on azimuth change based on information from the azimuth sensor and azimuth change based on GPS information when the azimuth change is performed. Correction coefficient calculation apparatus and program for azimuth sensor capable of appropriately calculating a correction coefficient for correcting azimuth sensor information on the basis of GPS information, and self-position recognition apparatus using the same And providing the program.

  In order to achieve the above object, the characteristic configuration of the correction coefficient calculation device of the azimuth sensor according to the present invention includes GPS information acquisition means for acquiring GPS information including position information and traveling azimuth information based on a signal from a GPS satellite; Direction sensor information acquisition means for acquiring direction sensor information from the direction sensor, and first straight advance determination means for determining whether or not the vehicle travels straight within a predetermined vicinity area set in the vicinity of the own position based on the GPS information A rear area setting means for setting a rear area spaced a predetermined distance rearward in the advancing direction with respect to the neighboring area when the first straight running judging means judges that the vehicle has traveled straight in the neighboring area, and the GPS GPS direction change amount calculating means for calculating an amount of change in direction between the traveling direction in the vicinity region and the traveling direction in the rear region based on the information; and Based on the amount, when it is determined that there has been a azimuth change by the GPS azimuth change determination means for determining whether or not there has been a azimuth change between the vicinity area and the rear area, Based on the azimuth sensor information, a second rectilinear determination means for determining whether or not the vehicle travels straight in both the vicinity area and the rear area, and the vicinity area and the rear area by the second rectilinear determination means. When it is determined that the vehicle travels straight in both areas, the direction change amount between the traveling direction in the neighboring area and the traveling direction in the rear area is calculated based on the direction sensor information. A sensor azimuth change amount calculating means; a correction coefficient calculating means for calculating a correction coefficient for correcting the azimuth sensor information based on the difference between the GPS azimuth change amount and the sensor azimuth change amount; In that it includes certain.

  According to this feature configuration, processing for calculating the correction coefficient is started when it is determined based on the GPS information that the vehicle has traveled straight in the vicinity region of its own position, so that unnecessary calculation processing is avoided. Therefore, it is possible to keep the calculation load of the apparatus low. In addition, only when it is determined that there is a azimuth change between the vicinity area and the rear area based on the GPS information and that the vehicle travels straight in both the vicinity area and the rear area based on the direction sensor information, Since the correction coefficient of the azimuth sensor is calculated, it is possible to increase the accuracy of the correction coefficient by reducing the influence of multiple azimuth changes.

  In addition, the characteristic configuration of the correction coefficient calculation program of the direction sensor according to the present invention for achieving the above object is a GPS information acquisition unit that acquires GPS information including position information and traveling direction information based on a signal from a GPS satellite. A first straight traveling determination step for determining whether or not the vehicle has traveled straight within a predetermined vicinity area based on the GPS information from the vehicle, and when it is determined by the first straight travel determination step that the vehicle has traveled straight within the vicinity area A rear region setting step for setting a rear region spaced a predetermined distance from the neighboring region, and based on the GPS information, between the traveling direction in the neighboring region and the traveling direction in the rear region Based on the GPS azimuth change amount calculation step for calculating the azimuth change amount and whether the azimuth change has occurred between the vicinity area and the rear area based on the GPS azimuth change amount. When it is determined that there has been a azimuth change by the GPS azimuth change determination step and the GPS azimuth change determination step, based on the azimuth sensor information from the azimuth sensor, both the vicinity area and the rear area In the second straight traveling determination step for determining whether or not the vehicle has traveled straight and the second straight travel determination step, it is determined that the vehicle has traveled straight in both the vicinity region and the rear region. Based on a sensor azimuth change amount calculating step for calculating a azimuth change amount between a traveling azimuth in the vicinity region and a traveling azimuth in the rear region, and the GPS azimuth change amount and the sensor azimuth change amount, And a correction coefficient calculation step of calculating a correction coefficient for correcting the azimuth sensor information based on the difference.

  Here, an azimuth change ratio calculation means for calculating a ratio between the GPS azimuth change amount and the sensor azimuth change amount, a storage means for storing information on the azimuth change ratio as a calculation result of the azimuth change ratio calculation means, It is preferable that the correction coefficient calculation unit calculates the correction coefficient based on an average value of all or a part of the plurality of azimuth change ratios stored in the storage unit.

  If comprised in this way, it will use the several azimuth | direction change ratio memorize | stored in the memory | storage means, the influence by the specific information in the calculation result of azimuth | direction change ratio is reduced, and it is based on an average azimuth | direction change ratio. Since the correction coefficient of the azimuth sensor can be calculated, the accuracy of the correction coefficient can be further improved.

  The azimuth sensor correction coefficient calculation program includes a azimuth change ratio calculation step for calculating a ratio between the GPS azimuth change amount and the sensor azimuth change amount after the sensor azimuth change amount calculation step, and the azimuth change ratio. A storage step of storing information on the azimuth change ratio as a calculation result of the calculation step in a predetermined storage unit, and in the correction coefficient calculation step, all of the plurality of azimuth change ratios stored in the storage unit Alternatively, it is preferable that the correction coefficient is calculated based on a partial average value.

  In addition, it is preferable that the rear region setting unit sequentially sets a plurality of regions having different distances from the neighboring region as the rear region.

  With this configuration, since a plurality of rear areas are set for one course change, the direction between a neighboring area and a rear area is determined based on GPS information for one neighboring area. There is a change, and it is possible to increase the possibility of setting a rear area that is determined to have traveled straight in both the vicinity area and the rear area based on the direction sensor information. Therefore, it is possible to increase the update frequency of the correction coefficient of the azimuth sensor, and it is possible to further improve the accuracy of the correction coefficient.

  Preferably, the azimuth sensor correction coefficient calculation program is configured to sequentially set a plurality of regions having different distances from the neighboring region as the rear region in the rear region setting step.

  In addition, the correction coefficient calculation means, based on the difference between the GPS azimuth change amount and the sensor azimuth change amount when the azimuth change is performed in each direction depending on whether the azimuth change direction is rightward or leftward, It is preferable that the correction coefficient for left and the correction coefficient for left are respectively calculated.

  With this configuration, even when the output characteristics of the azimuth sensor differ depending on whether the direction of azimuth change is rightward or leftward, an accurate correction coefficient can be calculated in accordance with each direction.

  Further, the correction coefficient calculation program for the azimuth sensor may include the GPS azimuth change amount and the sensor azimuth when the azimuth is changed in each direction according to whether the direction change is rightward or leftward in the correction coefficient calculation step. It is preferable that the right correction coefficient and the left correction coefficient are respectively calculated based on the difference from the change amount.

  The apparatus further comprises a plurality of azimuth change determination means for determining whether or not there have been a plurality of azimuth changes in different directions between the neighboring area and the rear area based on the azimuth sensor information. When it is determined that there have been a plurality of azimuth changes, it is preferable to omit the calculation of the correction coefficient between the neighboring area and the rear area.

  With this configuration, when the azimuth is changed in both the right and left directions between the neighboring area and the rear area, the calculation of the correction coefficient relating to the vicinity area and the rear area is omitted. When the output characteristics of the azimuth sensor differ depending on whether the orientation of the sensor is rightward or leftward, it can be prevented that it affects the correction coefficient. Therefore, it is possible to further reduce the influence of the complex orientation change and increase the accuracy of the correction coefficient.

  The correction coefficient calculation program for the azimuth sensor determines a plurality of azimuths based on the azimuth sensor information to determine whether or not there have been a plurality of azimuth changes in different directions between the neighboring area and the rear area. If the change determination step is further executed and it is determined that there have been a plurality of azimuth changes in different directions, it is preferable to omit the calculation of the correction coefficient relating to the vicinity region and the rear region.

  The characteristic configuration of the self position recognizing device according to the present invention is a self position recognizing device including the correction coefficient calculating device of the azimuth sensor configured as described above, and the correction coefficient calculating device follows the movement of the self position. Repeating the calculation of the correction coefficient and acquiring the distance sensor information from the direction sensor information correcting means for correcting the direction sensor information using the latest correction coefficient and the distance sensor information from the distance sensor detecting the moving distance And a self-position calculating means for calculating a movement locus of the self-position based on the corrected azimuth sensor information and the distance sensor information and recognizing the self-position.

  According to this feature configuration, the user's own position can be recognized based on the azimuth sensor information and the distance sensor information after correction using the correction coefficient. Therefore, when performing self-position recognition by autonomous navigation, high-precision self-position recognition is possible.

  Also, the characteristic configuration of the self-position recognition program according to the present invention is a self-position recognition program including the correction coefficient calculation program for the azimuth sensor configured as described above, wherein the correction coefficient calculation program The direction of the correction coefficient is repeatedly performed according to the direction sensor information correction step for correcting the direction sensor information using the latest correction coefficient, the corrected direction sensor information and the distance from the distance sensor for detecting the movement distance It is the point which makes a computer perform the self-position calculation step which calculates the movement locus | trajectory of a self-position based on sensor information, and recognizes a self-position.

  Here, the past direction sensor information is corrected using the latest correction coefficient, and the past movement trajectory of the current position is calculated again based on the corrected past direction sensor information and the past distance sensor information. And it is suitable if it is set as the structure provided with the self-position correction | amendment means which correct | amends the recognition result of a self-position.

  By configuring in this way, the past movement trajectory of the own position is calculated again based on the direction sensor information newly corrected using the latest correction coefficient, and the recognition result of the past own position is corrected. In the case of performing self-position recognition by the above, it becomes possible to perform self-position recognition with higher accuracy.

  Further, the self-position recognition program corrects the past direction sensor information using the latest correction coefficient, and based on the corrected past direction sensor information and the past distance sensor information, It is preferable to have a configuration including a self-position correcting step for calculating the movement locus of the head again and correcting the recognition result of the self-position.

[First embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. In the present embodiment, a description will be given by taking as an example a vehicle position recognition device 2 for a vehicle provided with a correction coefficient calculation device 1 for a direction sensor according to the present invention. FIG. 1 is a block diagram illustrating a schematic configuration of a vehicle position recognition device 2 according to the present embodiment.

The own vehicle position recognition device 2 according to the present embodiment is acquired from a gyro sensor 4 as an orientation sensor based on GPS information acquired by receiving a signal from a GPS (Global Positioning System) satellite by a GPS receiver 3. Based on the corrected gyro information and the pulse number information acquired from the distance sensor 5, the movement locus of the own vehicle position is calculated, and the current own vehicle position is recognized.
Hereinafter, based on FIG. 1, the structure of each part of the own vehicle position recognition apparatus 2 is demonstrated in detail. In addition, each function part and means of the own vehicle position recognition device 2 is a hardware or software (function or unit) for performing various processes on input data, with an arithmetic processing unit such as a CPU as a core member. Program) or both.

  The GPS receiver 3 receives a signal from a GPS satellite. Signals from this GPS satellite are received every second and sent to the GPS information acquisition unit 6. The GPS information acquisition unit 6 analyzes the received signal from the GPS satellite, information on the position (latitude and longitude) of the vehicle, the latest trip number information (hereinafter referred to as “GPS trip number information”) at the time of signal reception, Information such as traveling direction information, moving speed information, positioning satellite number information, error radius information, and height direction speed information is acquired, and GPS information including these pieces of information is generated. This GPS information is generated periodically every time a signal from a GPS satellite is received, that is, every second, and stored in the GPS information storage unit 7. Here, the GPS information acquisition unit 6 constitutes “GPS information acquisition means” in the present invention.

  In the vehicle position recognition device 2 according to the present embodiment, the minimum unit of the movement distance in the vehicle position recognition device 2 determined based on the movement distance of the vehicle position detected by the distance sensor 5 described later, that is, the unit. The distance is 1 trip. In this example, three pulses of the distance sensor 5 output signal are defined as one trip, and one trip is defined as about 1.2 [m]. The GPS trip number information is information indicating the latest number of trips at the time of receiving a signal from a GPS satellite that is a generation source of the GPS information.

  The gyro sensor 4 is a direction sensor that detects a change in the direction of the vehicle. As the gyro sensor 4, various types of gyroscopes such as a vibration gyroscope and an optical fiber gyroscope can be used. In this example, a vibration gyroscope is used. The gyro sensor 4 generates an output such as a voltage proportional to the rotational angular velocity around a predetermined detection axis. The output from the gyro sensor 4 is sent to the gyro information acquisition unit 8. The gyro information acquisition unit 8 performs analog / digital conversion for converting an output of an analog signal such as a voltage from the gyro sensor 4 into a digital signal, and generates a gyro output value composed of digital signals of a plurality of stages (for example, 256 stages). . Then, based on the generated gyro output value and the resolution per unit output value, gyro information representing the azimuth change amount is generated. Here, the gyro information is generated in the gyro information acquisition unit 8 for each trip with the movement of the vehicle position, and is stored in the gyro information storage unit 9. And the advancing direction of the own vehicle can be calculated | required by integrating | accumulating this gyro information. Here, the gyro sensor 4 corresponds to the “direction sensor” in the present invention, the gyro information corresponds to the “direction sensor information” in the present invention, and the gyro information acquisition unit 8 performs the “direction sensor information acquisition unit” in the present invention. Constitute.

  The distance sensor 5 is a sensor that detects the moving distance of the vehicle position. In this example, a vehicle speed pulse sensor is used as the distance sensor 5. The distance sensor 5 outputs a pulse signal every time a drive shaft or wheel of the vehicle rotates by a certain amount. The output from the distance sensor 5 is sent to the pulse number information acquisition unit 10. The pulse number information acquisition unit 10 integrates the number of pulses of the pulse signal output from the distance sensor 5 to generate pulse number information. Here, the pulse number information is generated by the pulse number information acquisition unit 10 for each trip (three pulses in this example) with the movement of the vehicle position, and is stored in the pulse number information storage unit 11. The movement distance is calculated by multiplying the difference in pulse number information between any two points stored in the pulse number information storage unit 11 by the standard distance per pulse (0.4 [m] in this example). be able to. By combining the travel distance information calculated from the pulse number information and the traveling direction information calculated from the gyro information, it is possible to recognize the position of the vehicle by autonomous navigation. Here, the pulse number information corresponds to “distance sensor information” in the present invention, and the pulse number information acquisition unit 10 constitutes “distance sensor information acquisition means” in the present invention.

The region setting unit 12 includes a neighborhood region setting unit 13 and a rear region setting unit 14. The neighborhood area setting means 13 is a means for setting a predetermined neighborhood area arA in the vicinity of the vehicle position. Further, the rear area setting means 14 is a means for setting the rear areas arB, arC,... Separated by a predetermined distance rearward in the traveling direction with respect to the neighboring area arA. The neighboring area arA and the rear areas arB, arC... Will be described with reference to FIG.
FIG. 2 is a schematic diagram illustrating an example of a relationship between GPS information and gyro information before and after a change in direction (right turn). In this figure, the GPS locus Lg represents the movement locus of the own vehicle position based on the GPS information, and the sensor locus Ls represents the movement locus of the own vehicle position calculated based on the pulse number information and the gyro information. On the GPS locus Lg, GPS information A1 to A3, B1 to B3, and the like used for calculation are represented by circles, and the traveling direction indicated by each GPS information is represented by an arrow. On the sensor locus Ls, the position of a predetermined point used for calculation is represented by a circle. Here, each point on the sensor locus Ls is defined based on the number of trips, and is associated with each GPS information having GPS trip number information based on the number of trips.

As shown in FIG. 2, in this example, the neighborhood area arA selects the GPS information A1 to A3 from the current point Pg0, which is the current number of trips, to the previous three points, and then sets the current point Pg0 as the front end. A point Pg1 retroactive to the rear of the 10-trip traveling direction with respect to the number of trips indicated in the GPS trip number information of the GPS information A3 is set as a rear end region. Here, the names of the GPS information are A1, A2, and A3 in order from the front side in the traveling direction. The points on the sensor locus Ls corresponding to the GPS information A1, A2, and A3 are Pa1, Pa2, and Pa3, respectively.
Further, in this example, the rear area arB selects the GPS information B1 to B3 from the current point Pg0 to the previous three points as a reference point, and points to the GPS trip B1 of the GPS information B1. The point Pg2 that has advanced forward in the 10-trip traveling direction with respect to the number of trips indicated in the GPS trip number information is used as the front end, and the number of trips indicated in the GPS trip number information in the GPS information B3 is traced backward in the 10-trip traveling direction. It is set in a region having the point Pg3 as the rear end. Here, the names of the GPS information are B1, B2, and B3 in order from the front side in the traveling direction. The points on the sensor locus Ls corresponding to the GPS information B1, B2, and B3 are Pb1, Pb2, and Pb3, respectively.
Further, the rear area setting means 14 performs processing for sequentially setting a plurality of areas having different distances from the neighboring area arA as the rear areas arB, arC. Therefore, also in the rear area arC and later, for example, 150 points, 200 trips, 250 trips, 300 trips, 350 trips, and 400 trips in the rearward direction from the current point Pg0 are used as reference points in order, and the rear area Set up to arC, arD ... arH. In the following description, the case where the rear area arB is set will be basically described. However, the same processing is performed even when other rear areas arC, arD... ArH are set. Is called.

As shown in FIG. 1, the GPS condition determination unit 15 includes a GPS straight travel determination unit 16, a speed determination unit 17, a reception state determination unit 18, and a GPS direction change determination unit 19.
The GPS straight travel determination means 16 is a means for determining whether or not the vehicle position has traveled straight within the vicinity area arA based on GPS information. In this example, the GPS straight traveling determination means 16 is based on the traveling direction information included in the GPS information A1, A2, and A3, and between the GPS information A1 and A2, A2 and A3, and A1 and A3. It is determined whether or not the absolute value of the azimuth change amount is 3 [°] or less. Here, the GPS straight travel determination means 16 constitutes the “first straight travel determination means” in the present invention.

The speed determination means 17 is a means for determining whether or not the host vehicle is traveling at a predetermined speed or higher based on the GPS information. In this example, based on the movement speed information included in the GPS information A1, A2, and A3, it is determined whether or not the speed of all the GPS information A1, A2, and A3 is 5 [m / s] or more. .
The reception state determination unit 18 is a unit that determines whether the reception state of the signal from the GPS satellite when the GPS information is acquired is good or bad. In this example, based on the positioning satellite number information included in the GPS information A1, A2, and A3, it is determined whether or not the number of positioning satellites is four in all of the GPS information A1, A2, and A3.
The GPS azimuth change determination means 19 changes the azimuth between the vicinity area arA and the rear area arB based on the GPS azimuth change ang-GPS (see FIG. 2) calculated by the GPS azimuth change calculation means 22 described later. It is means for determining whether or not there has been. In this example, it is determined whether or not the absolute value of the GPS azimuth change amount ang-GPS is 60 ° to 120 ° (60 ° ≦ | ang−GPS | ≦ 120 °).

The GPS information calculation unit 20 includes a GPS direction calculation means 21 and a GPS direction change amount calculation means 22.
The GPS azimuth calculating means 21 is a means for calculating a traveling azimuth in the vicinity area arA and a traveling azimuth in the rear area arB based on GPS information. In this example, as shown in FIG. 2, the GPS azimuth calculating means 21 is based on the traveling azimuth information included in the GPS information A1, A2, A3, and the average value of the traveling azimuth included in the GPS information A1, A2, A3. Is set as the GPS azimuth ang-A in the vicinity area arA. Further, the GPS azimuth calculating means 21 calculates the average value of the traveling azimuth included in the GPS information B1, B2, B3 based on the traveling azimuth information included in the GPS information B1, B2, B3, and calculates the average value of the rear area arB GPS direction ang-B in the inside.
The GPS azimuth change calculation means 22 calculates the difference between the GPS azimuth ang-A in the vicinity area arA and the GPS azimuth ang-B in the rear area arB calculated by the GPS azimuth calculation means 21, and the GPS azimuth change ang− Calculate as GPS. Here, the value of the GPS azimuth change ang-GPS is positive when the azimuth is changed to the right, and the value of the GPS azimuth change ang-GPS is negative when the azimuth is changed to the left. is doing. Of course, it is also possible to reverse the left-right and positive-negative relationship.

The sensor condition determination unit 23 includes a straight sensor determination unit 24, a sensor orientation change determination unit 25, and a plurality of orientation change determination units 26.
The straight sensor determination unit 24 is a unit that determines whether or not the vehicle position has traveled straight in both the vicinity area arA and the rear area arB based on the gyro information. In this example, as shown in FIG. 2, the sensor straight-advancing determining means 24 has an absolute value of the azimuth change amount between the current point Pg0 and the point Pg1, which is a point at both ends of the vicinity area arA, of 3 [°] or less. And the absolute value of the azimuth change amount between the points Pg2 and Pg3, which are both ends of the rear region arB, is determined to be 3 [°] or less. Here, the sensor straight travel determination means 24 constitutes the “second straight travel determination means” in the present invention.
The sensor azimuth change determination means 25 changes the azimuth between the vicinity area arA and the rear area arB based on a sensor azimuth change amount ang-SEN (see FIG. 2) calculated by a sensor azimuth change amount calculation means 29 described later. It is means for determining whether or not there has been. In this example, it is determined whether or not the absolute value of the sensor orientation change amount ang-SEN is 30 ° or more (30 ° ≦ | ang−SEN |).

  The multiple azimuth change determination means 26 is a means for determining whether or not there have been multiple azimuth changes in different directions between the vicinity area arA and the rear area arB based on the gyro information. In this example, the plurality of azimuth change determination means 26 are used when the azimuth changes in both the right direction and the left direction based on the straight traveling state based on the gyro information between the neighboring area arA and the rear area arB. It is determined that the direction has been changed. When it is determined by the multiple azimuth change determination means 26 that there have been multiple azimuth changes, the calculation of the correction coefficient relating to the neighborhood area arA and the rear area arB is omitted. Thus, for example, as shown in FIG. 3, even if the azimuth is changed to the right as a whole between the rear end point Pg1 of the neighboring area arA and the front end point Pg2 of the rear area arB, When the direction is finely changed from left to right, the information between the neighboring area arA and the rear area arB is excluded from the information on the correction coefficient calculation target.

The sensor information calculation unit 27 includes a sensor direction calculation unit 28 and a sensor direction change amount calculation unit 29.
The sensor azimuth calculation means 28 is a means for calculating the traveling azimuth in the vicinity area arA and the traveling azimuth in the rear area arB based on the gyro information. In this example, as shown in FIG. 2, the sensor direction calculation means 28 is connected to the number of trips (points Pa1, Pa2, Pa3 on the sensor locus Ls) indicated by the GPS trip number information included in the GPS information A1, A2, A3. The point Pma having the number of trips closest to the average value of the correspondence) is determined as a representative point representing the neighboring area arA. And let the advancing direction based on the gyro information in this point Pma be sensor direction ang-Pma of the vicinity area arA. Here, the traveling azimuth at the point Pma can be calculated by successively integrating the azimuth change amounts indicated in the gyro information starting from the traveling azimuth of the host vehicle acquired last time. In addition, the sensor azimuth calculating means 28 is the trip closest to the average value of the trip numbers (corresponding to the points Pb1, Pb2, Pb3 on the sensor locus Ls) indicated by the GPS trip number information included in the GPS information B1, B2, B3. A number of points Pmb are determined as representative points representing the rear region arB. Then, the traveling direction based on the gyro information at the point Pmb is defined as the sensor direction ang-Pmb of the rear region arB. Here, the traveling azimuth at the point Pmb can be calculated by successively integrating the azimuth change amounts indicated in the gyro information starting from the traveling azimuth of the host vehicle acquired last time.
The sensor azimuth change amount calculation means 29 calculates a difference between the sensor azimuth ang-Pma in the vicinity area arA calculated by the sensor azimuth calculation means 28 and the sensor azimuth ang-Pmb in the rear area arB as a sensor azimuth change amount ang-SEN. Calculate. Here, the value of the sensor azimuth change amount ang-SEN is positive when the azimuth is changed to the right, and the value of the sensor azimuth change ang-SEN is negative when the azimuth is changed to the left. is doing. Of course, it is also possible to reverse the left-right and positive-negative relationship.

The azimuth change ratio calculation unit 30 is a ratio between the GPS azimuth change amount ang-GPS calculated by the GPS azimuth change amount calculation means 22 and the sensor azimuth change amount ang-SEN calculated by the sensor azimuth change amount calculation means 29. It is a means for calculating a certain direction change ratio. Specifically, the calculation is performed by the following equation (1).
(Direction change ratio) = ang-SEN / | ang-GPS | (1)
Here, the numerator is the sensor orientation change amount ang-SEN, and the denominator is the absolute value of the GPS orientation change amount ang-GPS. This is so that the value of the azimuth change ratio becomes positive when the azimuth changes in the right direction, and the value of the azimuth change ratio becomes negative when the azimuth changes in the left direction. That is, the values of the GPS azimuth change amount ang-GPS and the sensor azimuth change amount ang-SEN are both set to be positive when the azimuth changes to the right and negative when the azimuth changes to the left. Yes. Therefore, if either one of the GPS azimuth change amount ang-GPS and the sensor azimuth change amount ang-SEN is an absolute value, the value of the azimuth change ratio can be made to be different between right and left. Therefore, the sensor orientation change amount ang-SEN can be an absolute value. Here, this azimuth change ratio calculation unit 30 constitutes “azimuth change ratio calculation means” in the present invention.

  Further, in this example, the azimuth change ratio calculation unit 30 has an absolute value of the azimuth change ratio calculated by the above formula (1) within an allowable range, specifically 0.5 to 1.1 (0.5 ≦ | It is determined whether or not the azimuth change ratio | ≦ 1.1). Then, the azimuth change ratio calculation unit 30 performs a process of correcting the value within the allowable range when the value is outside the allowable range. Specifically, when the absolute value of the azimuth change ratio is less than 0.5, the absolute value of the azimuth change ratio is corrected to 0.5, and the absolute value of the azimuth change ratio is greater than 1.1. Corrects the absolute value of the azimuth change ratio to 1.1. In general, since the sensor azimuth change amount ang-SEN is often smaller in absolute value than the GPS azimuth change amount ang-GPS, the allowable range in this example is set to a wide range of 1 or less. ing.

  The ratio storage unit 31 is a unit that stores information on the azimuth change ratio as a calculation result by the azimuth change ratio calculation unit 30. The ratio calculation unit 31 includes a memory and a buffer, and can store information on a plurality of azimuth change ratios. Here, the ratio storage unit 31 constitutes “storage means” in the present invention.

  The correction coefficient calculator 32 is a means for calculating a correction coefficient D for correcting gyro information based on the difference between the GPS azimuth change amount ang-GPS and the sensor azimuth change amount ang-SEN. Specifically, the correction coefficient calculation unit 32 calculates the correction coefficient D based on an average value of all or some of the plurality of azimuth change ratios stored in the ratio storage unit 31. In this example, an average value of the latest eight azimuth change ratios stored in the ratio storage unit 31 is calculated, and a calculation process using the value as the correction coefficient D is performed. The calculation of the correction coefficient D is repeatedly performed according to the movement of the own vehicle position. Here, the correction coefficient calculator 32 constitutes “correction coefficient calculator” in the present invention.

  Further, in this example, the correction coefficient calculation unit 32 determines whether the azimuth change direction is the right direction or the left direction, and the GPS azimuth change amount ang-GPS and the sensor azimuth change amount ang-SEN when the azimuth change is performed in each direction. The right correction coefficient Dr and the left correction coefficient Dl are calculated based on the difference between the left correction coefficient Dr and the right correction coefficient Dr. That is, as described above, the value of the azimuth change ratio is set to be positive when the azimuth is changed in the right direction, and negative when the azimuth is changed in the left direction. Therefore, the right correction coefficient Dr is calculated using only the azimuth change ratio having a positive value, and the left correction coefficient D1 is calculated using only the azimuth change ratio having a negative value. In the description of the present embodiment, when the correction coefficient D is simply referred to, the right correction coefficient Dr and the left correction coefficient Dl are collectively referred to.

The gyro information correction unit 33 is a unit that corrects the gyro information using the latest correction coefficient D calculated by the correction coefficient calculation unit 32. In this example, the gyro information correction unit 33 acquires the corrected gyro information by multiplying the gyro information acquired by the gyro information acquisition unit 8 by the reciprocal of the correction coefficient D. Specifically, the calculation is performed by the following equation (2).
(Gyro information after correction) = (Gyro information) × (1 / D) (2)
As described above, the gyro information is information representing the amount of azimuth change generated based on the output value of the gyro sensor 4 and the resolution per unit output value. On the other hand, as described above, the correction coefficient D is an average value of a plurality (eight in this example) of azimuth change ratios (= ang−SEN / | ang−GPS |). Therefore, the corrected gyro information calculated by multiplying the gyro information by the reciprocal of the correction coefficient D reflects the difference between the recent GPS azimuth change ang-GPS and the sensor azimuth change ang-SEN. It is corrected and represents an azimuth change amount close to the azimuth change amount based on GPS information. Here, the gyro information correction unit 33 constitutes “direction sensor information correction means” in the present invention.

  The own position calculation unit 34 calculates the movement locus of the own vehicle position based on the corrected gyro information and the pulse number information. That is, the own position calculation unit 34 uses the pulse number information acquisition unit 10 to obtain the pulse number information and the gyro information starting from the position and traveling direction of the own vehicle calculated in the previous time stored in the own position storage unit 35 described later. Based on the gyro information corrected by the correction unit 33, the movement locus of the vehicle position from the starting point is obtained. Here, the calculation of the movement trajectory of the own vehicle position is performed by calculating the pulse number information toward the traveling direction of the own vehicle calculated based on the traveling direction at the starting point and the direction change amount indicated in the corrected gyro information. This is performed by moving from the position of the starting point by a moving distance calculated by multiplying by a predetermined standard distance. Based on this movement trajectory, the position and traveling direction of the host vehicle are calculated. The position and traveling direction of the host vehicle are periodically calculated at least every second here when GPS information is acquired by the GPS information acquisition unit 6. The calculation result by the own position calculation unit 34 is stored in the own position storage unit 35 as the current position and traveling direction of the own vehicle. Further, the information on the position and traveling direction of the own vehicle is sent as an output of the own vehicle position recognizing device 2 to a navigation device, a vehicle control device, etc. (not shown). Here, the own position calculation unit 34 constitutes “own position calculation means” in the present invention.

  The own position storage unit 35 is a storage unit that stores information on the position and traveling direction of the own vehicle that has been sequentially recognized until the previous time. The information on the position and traveling direction of the host vehicle so far stored in the host position storage unit 35 is sent to the own position calculating unit 34 and used for calculation of the current position and traveling direction of the host vehicle. .

  Next, calculation processing of the correction coefficient D by the correction coefficient calculation device 1 according to this embodiment and recognition processing of the own vehicle position by the own vehicle position recognition device 2 will be described using the flowcharts shown in FIGS.

  First, the calculation process of the correction coefficient D will be described with reference to FIGS. Each calculation processing step described below is executed by each functional unit and means of the correction coefficient calculation device 1 that operates according to the correction coefficient calculation program. In this process, first, as shown in FIG. 2, the vicinity area arA is set by the vicinity area setting means 13 on the basis of the current vehicle position (step # 01). Next, in steps # 02 to # 04, it is determined whether or not the GPS information in the vicinity area arA satisfies a predetermined calculation start condition. This calculation start condition is a condition that the vehicle position is traveling straight in the vicinity area arA and that the signal reception state from the GPS satellite is good. That is, in step # 02, the GPS straight traveling determination means 16 determines whether or not the GPS information indicates a straight traveling state in the vicinity area arA. Specifically, as described above, it is determined whether or not the absolute value of the azimuth change amount between the GPS information A1 and A2, A2 and A3, and A1 and A3 is 3 [°] or less. To do. In step # 03, the speed determination means 17 determines whether or not the GPS information indicates a traveling state in the vicinity area arA. Specifically, as described above, it is determined whether all of the GPS information A1, A2, and A3 have a speed of 5 [m / s] or more. In step # 04, the reception state determination means 18 determines whether the reception state of the signal from the GPS satellite when the GPS information is acquired is good or bad. Specifically, as described above, it is determined whether or not the number of positioning satellites is four in all of the GPS information A1, A2, and A3. In addition, the order of these steps # 02 to # 04 is not particularly limited, and can be exchanged. If any of these conditions of Steps # 02 to # 04 is not satisfied, the subsequent calculation process of the correction coefficient D is not executed.

  When all the conditions of steps # 02 to # 04 are satisfied, next, as shown in FIG. 2, the sensor azimuth calculation means 28 calculates the representative point Pma of the neighboring area arA, and the GPS azimuth calculation means 21 To calculate the GPS azimuth ang-A in the vicinity area arA (step # 05). Next, the rear area arB is set by the rear area setting means 14 as shown in FIG. 2 (step # 06). Then, the sensor azimuth calculating means 28 calculates the representative point Pmb of the rear area arB, and the GPS azimuth calculating means 21 calculates the GPS azimuth ang-B in the rear area arB (step # 07). Thereafter, the GPS azimuth change calculating means 22 calculates the difference between the GPS azimuth ang-A in the vicinity area arA and the GPS azimuth ang-B in the rear area arB as the GPS azimuth change ang-GPS (step #). 08).

  Whether the absolute value of the GPS azimuth change amount ang-GPS calculated in step # 08 is 60 ° or more and 120 ° or less (60 ° ≦ | ang−GPS | ≦ 120 °) by the GPS azimuth change determination means 19. It is determined whether or not (step # 09). Thereby, it is determined based on the GPS information whether or not there has been a change in direction between the vicinity area arA and the rear area arB. If there is an azimuth change between the vicinity area arA and the rear area arB (step # 09: YES), then the sensor straight-ahead determination means 24 indicates that the gyro information includes both the vicinity area arA and the rear area arB. It is determined whether or not a straight traveling state is indicated within the area (step # 10). Specifically, as described above, the absolute value of the azimuth change amount between the current point Pg0 and the point Pg1, which are the points at both ends of the neighboring area arA, is 3 [°] or less, and both ends of the rear area arB. It is determined whether or not the absolute value of the azimuth change amount between the point Pg2 and the point Pg3 is 3 [°] or less. If the condition is not satisfied in step # 09 or # 10, the process proceeds to step # 17, and the process for the next rear area arC is executed.

  When the gyro information indicates a straight traveling state in both the vicinity area arA and the rear area arB (step # 10: YES), the sensor direction calculation means 28 causes the sensor direction ang-Pma of the vicinity area arA to be detected. And the sensor orientation ang-Pmb of the rear area arB is calculated (step # 11). Then, the difference between the sensor orientation ang-Pma in the vicinity area arA and the sensor orientation ang-Pmb in the rear area arB is calculated as the sensor orientation change amount ang-SEN by the sensor orientation change amount calculation means 29 (step # 12). .

  Next, the sensor orientation change determination means 25 determines whether or not the absolute value of the sensor orientation change amount ang-SEN calculated in step # 12 is 30 ° or more (30 ° ≦ | ang−SEN |). (Step # 13). As a result, whether or not there has been a change in direction between the vicinity area arA and the rear area arB is determined based on the gyro information. If the absolute value of the sensor orientation change amount ang-SEN is less than 30 ° (step # 13: NO), the process proceeds to step # 17, and the process for the next rear area arC is executed.

  On the other hand, when the absolute value of the sensor azimuth change amount ang-SEN is 30 ° or more (step # 13: YES), for example, as shown in FIG. It is determined whether or not there have been multiple azimuth changes in different directions between the vicinity area arA and the rear area arB (step # 14). If there are a plurality of azimuth changes in different directions (step # 15: YES), the calculation of the correction coefficient relating to the vicinity area arA and the rear area arB is omitted, and the process ends.

  On the other hand, if there are no azimuth changes in different directions (step # 15: NO), the azimuth change ratio calculation unit 30 calculates the GPS azimuth change ang-GPS calculated in step # 08 and step # 12. The azimuth change ratio is calculated based on the sensor azimuth change amount ang-SEN calculated in (Step # 16). Specifically, the azimuth change ratio is calculated by the above formula (1) as a ratio in which the numerator is the sensor azimuth change amount ang-SEN and the denominator is the absolute value of the GPS azimuth change amount ang-GPS. And the information of the calculated azimuth | direction change ratio is memorize | stored in the ratio memory | storage part 31 (step # 17). By performing the above processing, for example, when changing the direction such as turning left or right at an intersection, the state of the vehicle returns to the straight-ahead state after the direction is changed from the straight-ahead state to one direction. In this case, the azimuth change ratio is calculated and stored in the ratio storage unit 31.

  Thereafter, it is determined whether or not the processing of steps # 07 to # 17 has been completed for all the rear areas arB, arC, arD... ArH (step # 18). That is, in this example, seven areas from arB to arH having different distances from the neighboring area arA are sequentially set as the rear area. Therefore, when the process for all the rear areas arB, arC, arD... ArH is not completed (step # 18: NO), after the process is completed for one rear area, for example, arB, Is set, for example, arC (step # 19). And the process of step # 07- # 17 is similarly performed about the said following back area | region.

  Thereafter, when the process for the last rear area arH is completed (step # 18: YES), it is next determined whether or not eight or more pieces of direction change ratio information are stored in the ratio storage unit 31. (Step # 20). Here, when the number of the azimuth change ratio information stored in the ratio storage unit 31 is less than eight (step # 20: NO), the azimuth change ratio information is used to calculate the correction coefficient D. Since the amount is small, the value of the correction coefficient D is set to a predetermined initial value (step # 21). Then, the calculation process of the correction coefficient D ends. On the other hand, when the number of azimuth change ratio information stored in the ratio storage unit 31 is 8 or more (step # 20: YES), the correction coefficient calculation unit 32 calculates the correction coefficient D (step # 20). # 22). Specifically, as described above, the average value of the latest eight azimuth change ratios stored in the ratio storage unit 31 is calculated, and the value is set as the correction coefficient D. At this time, the right correction coefficient Dr and the left correction coefficient Dl are respectively calculated according to whether the direction of the azimuth change is rightward or leftward. Then, the value of the correction coefficient D is updated to the value calculated in step # 22 (step # 23), and the calculation process of the correction coefficient D is terminated.

  Next, the vehicle position recognition process will be described with reference to FIG. Each calculation processing step described below is executed by each functional unit and means of the vehicle position recognition device 2 that operates according to the own position recognition program. In this process, first, the correction coefficient D is calculated (step # 101). The calculation process of the correction coefficient D is as already described with reference to FIGS. Then, the gyro information correction unit 33 corrects the gyro information using the latest correction coefficient D calculated in step # 101 (step # 102). Specifically, the corrected gyro information is calculated by multiplying the uncorrected gyro information by the reciprocal of the correction coefficient D by the above equation (2). Thereby, the gyro information (corrected gyro information) representing the azimuth change amount corrected based on the GPS information is acquired.

  Next, the own position calculation unit 34 calculates the movement locus of the own vehicle position based on the corrected gyro information and the pulse number information. Specifically, the vehicle position and traveling direction calculated in the previous time stored in the own position storage unit 35 are used as starting points, and the calculation is based on the moving direction at the starting point and the direction change amount indicated in the corrected gyro information. The moving locus of the vehicle position is calculated assuming that the vehicle has moved from the starting position by the moving distance calculated by multiplying the pulse number information by a predetermined standard distance in the traveling direction of the vehicle. Based on this movement locus, the vehicle position is recognized, that is, the position and traveling direction of the vehicle are recognized (step # 104). Thereafter, when the position of the host vehicle is moving (step # 105: YES), the process returns to step # 101, and further, the position of the host vehicle is recognized (step # 101) from the calculation process of the correction coefficient D (step # 101). The processes up to # 104) are repeated. And when the own vehicle stops (step # 105: NO), the own vehicle position recognition process is complete | finished.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. FIG. 7 is a block diagram showing a schematic configuration of the vehicle position recognition device 2 according to the present embodiment. As shown in this figure, the vehicle position recognition device 2 according to the present embodiment corrects the movement locus of the past vehicle location stored in the vehicle location storage unit 35 based on the correction coefficient D. Is different from the configuration of the first embodiment. Hereinafter, differences from the first embodiment will be described.

  The own position correcting unit 36 corrects the past gyro information using the latest correction coefficient D, and recalculates the past movement locus of the own vehicle position based on the corrected past gyro information and the past pulse number information. And means for correcting the recognition result of the own position. Here, the self-position correcting unit 36 constitutes “self-position correcting means” in the present invention. In the present embodiment, the own position storage unit 35 stores information on the position and traveling direction of the own vehicle recognized so far. That is, these pieces of information are stored as the movement locus of the vehicle position and the amount of change in the traveling direction. The own position storage unit 35 also includes gyro information indicating the amount of azimuth change at each point used for generating information on the position and traveling direction of the own vehicle, and pulse number information that is a calculation source of the moving distance. It is remembered.

  Also in the present embodiment, the condition for calculating the azimuth change ratio is the same as in the first embodiment, for example, when the azimuth change such as a right or left turn at an intersection is performed, When returning to the straight traveling state after the azimuth change is performed in one direction, the azimuth change ratio related to the azimuth change is calculated and stored in the ratio storage unit 31. Then, when information of eight or more azimuth change ratios is already stored in the ratio storage unit 31, a new correction coefficient D is calculated every time a new azimuth change ratio is stored. Therefore, in the present embodiment, the own position storage unit 35, when a new correction coefficient D is calculated, the own vehicle position in the direction change related to the direction change ratio from which the correction coefficient D is calculated. The movement locus is calculated again and corrected.

  For example, as shown in FIG. 2, when the azimuth change ratio is calculated between the vicinity area arA and the rear area arB, and a new correction coefficient D is calculated using the azimuth change ratio, the self-position correction unit 36 Is between the neighboring area arA and the rear area arB stored in the self-position storage unit 35 using the latest correction coefficient D, more specifically, the rear end point Pg1 of the neighboring area arA and the front end of the rear area arB. A sensor locus Ls, which is a past movement locus of the vehicle position between the point Pg2 and the vehicle, is calculated again. At this time, the past gyro information stored in the own position storage unit 35 is corrected using the latest correction coefficient D, and the corrected past gyro information and the past pulse number information stored in the own position storage unit 35 are corrected. Based on the above, the past movement locus of the vehicle position is calculated again. The recalculation result is output to the own position calculation unit 34, and the position and traveling direction of the own vehicle are calculated again.

  As a result, when the azimuth change is performed, the correction coefficient D calculated using the azimuth change ratio that is the ratio of the GPS azimuth change amount ang-GPS and the sensor azimuth change amount ang-SEN at the time of the azimuth change. Then, the movement locus of the vehicle position in the azimuth change is calculated again. Therefore, based on the difference between the latest GPS azimuth change amount ang-GPS and the sensor azimuth change amount ang-SEN, the vehicle position recognition and the vehicle direction recognition can be performed with higher accuracy.

[Other Embodiments]
(1) In the above embodiment, the correction coefficient calculation unit 32 calculates the average value of the latest eight azimuth change ratios stored in the ratio storage unit 31 and sets the value as the correction coefficient D. explained. However, the calculation method of the correction coefficient D is not limited to this. That is, for example, calculating the correction coefficient D using a histogram as shown in FIG. 8 is also one preferred embodiment. That is, in this histogram, the horizontal axis represents the azimuth change ratio, and the vertical axis represents the frequency. Then, a frequency is given to each azimuth change ratio calculated by the azimuth change ratio calculation unit 30 and registered in the histogram. This histogram is stored in the ratio storage unit 31. When the number of registrations exceeds a certain number (for example, 100 or more), the average value of the azimuth change ratios registered in the histogram is calculated. At this time, a range of standard deviation σ is set on both sides from the overall average value of the histogram, an average value of the azimuth change ratios within this range is calculated, and this is set as a correction coefficient D. Thereby, the correction coefficient D is calculated based on the average value of a part of the plurality of azimuth change ratios stored in the ratio storage unit 31.

(2) In the above embodiment, the case where the reception state determination unit 18 determines only the number of positioning satellites as the reception state of signals from GPS satellites has been described. However, it is also a preferred embodiment to determine the reception status of signals from other GPS satellites. As such a reception state determination condition, for example, an error radius condition indicated in error radius information included in GPS information can be used. That is, for example, when the error radius is 300 [m] or less, it can be determined that the reception state is good.

(3) In order to improve the accuracy of the correction coefficient D, it is preferable that the determination conditions in the GPS straight-line determination means 16 and the speed determination means 17 are made more stringent. For example, in the above-described embodiment, the GPS straight traveling determination means 16 has an absolute value of the azimuth change amount between the GPS information A1 and A2, A2 and A3, and A1 and A3 of 3 [°] or less. However, it is also preferable to set it to 1.5 [°] or less, or 0.7 [°] or less. In the above embodiment, the speed determination means 17 determines whether or not the speed is 5 [m / s] or more in all of the GPS information A1, A2, and A3. .5 [m / s] or more is also suitable.

(4) Similarly, in order to improve the accuracy of the correction coefficient D, it is preferable that the determination condition in the sensor straight-ahead determination unit 24 is further strict. For example, in the above embodiment, the sensor straight-ahead determination means 24 has an absolute value of the azimuth change amount between the current point Pg0 and the point Pg1, which are the points at both ends of the vicinity area arA, of 3 [°] or less. In addition, it is determined whether or not the absolute value of the azimuth change amount between the points Pg2 and Pg3, which are both ends of the rear region arB, is 3 [°] or less. It is also suitable as below.

(5) In the above-described embodiment, a case has been described in which the GPS straight traveling determination unit 16, the speed determination unit 17, and the reception state determination unit 18 perform determination only on the GPS information A1, A2, and A3 in the vicinity area arA. . However, it is also one preferred embodiment that the GPS straight-running determination unit 16, the speed determination unit 17, and the reception state determination unit 18 are configured to perform the same determination for each of the rear areas arC, arD. It is. In this case, as a specific processing procedure, for example, after the rear area arB is set in step # 06 of FIG. 4, the same determination process as in steps # 02 to # 04 is performed before the process of step # 07. This is performed for the area arB. If all of these determination conditions are satisfied, the process proceeds to step # 07. On the other hand, if any of these determination conditions is not satisfied, the process proceeds to step # 18. Here, since the processing has not been completed for all the rear areas arB, arC, arD... ArH (step # 18: NO), the next rear area arC is set (step # 19). In this way, the same determination process as in steps # 02 to # 04 is performed for all the rear regions arB, arC, arD... ArH, and only the rear region satisfying these determination conditions is used for the calculation of the azimuth change ratio. Use.

(6) In the above embodiment, the vehicle position recognition device 2 of the vehicle has been described as an example. However, the present invention is applied to a self-position recognition device or the like of a vehicle other than a vehicle or a vehicle such as a ship. Is of course possible.

  It was possible to obtain a correction coefficient calculation device and calculation program for an azimuth sensor that can accurately correct output information from the azimuth sensor using a signal from a GPS satellite, and a self-position recognition device and a recognition program.

The block diagram which shows schematic structure of the own vehicle position recognition apparatus which concerns on 1st embodiment of this invention. Schematic diagram showing an example of the relationship between GPS information and gyro information before and after the azimuth change Schematic diagram showing an example of gyro information when there are multiple heading changes The flowchart which shows the calculation process of the correction coefficient which concerns on 1st embodiment of this invention. The flowchart which shows the calculation process of the correction coefficient which concerns on 1st embodiment of this invention. The flowchart which shows the recognition process of the own vehicle position which concerns on 1st embodiment of this invention. The block diagram which shows schematic structure of the own vehicle position recognition apparatus which concerns on 2nd embodiment of this invention. Histogram for calculating a correction coefficient according to another embodiment of the present invention

Explanation of symbols

1: Correction coefficient calculation device 2: Own vehicle position recognition device 4: Gyro sensor (direction sensor)
5: Distance sensor 6: GPS information acquisition unit (GPS information acquisition means)
8: Gyro information acquisition unit (direction sensor information acquisition means)
10: Pulse number information acquisition unit (distance sensor information acquisition means)
14: Rear area setting means 16: GPS straight-ahead determination means (first straight-ahead determination means)
19: GPS azimuth change determination means 22: GPS azimuth change amount calculation means 24: Sensor straight-ahead determination means (second straight-ahead determination means)
26: Multiple-direction azimuth change determination means 29: Sensor azimuth change amount calculation means 30: Direction change ratio calculation section (azimuth change ratio calculation means)
31: Ratio storage unit (storage means)
32: Correction coefficient calculation unit (correction coefficient calculation means)
33: Gyro information correction unit (direction sensor information correction means)
34: Own position calculation unit (own position calculation means)
arA: Neighborhood area arB, arC ...: Rear area ang-GPS: GPS azimuth change ang-SEN: Sensor azimuth change

Claims (14)

GPS information acquisition means for acquiring GPS information including position information and traveling direction information based on a signal from a GPS satellite;
Direction sensor information acquisition means for acquiring direction sensor information from the direction sensor;
First straight traveling determination means for determining whether or not the vehicle travels straight within a predetermined vicinity area set in the vicinity of the own position based on the GPS information;
A rear region setting unit that sets a rear region that is separated by a predetermined distance rearward in the traveling direction with respect to the neighboring region when the first straight traveling determining unit determines that the vehicle has traveled straight in the neighboring region;
GPS azimuth change amount calculating means for calculating an azimuth change amount between the traveling azimuth in the vicinity region and the traveling azimuth in the rear region based on the GPS information;
GPS azimuth change determining means for determining whether or not there has been a azimuth change between the vicinity area and the rear area based on the GPS azimuth change amount;
When the GPS azimuth change determining means determines that there has been a azimuth change, based on the azimuth sensor information, it determines whether or not the vehicle has traveled straight in both the neighborhood area and the rear area. A determination means;
When it is determined by the second straight traveling determination means that the vehicle has traveled straight in both the vicinity area and the rear area, the traveling direction in the vicinity area and the rear area are determined based on the direction sensor information. Sensor azimuth change amount calculating means for calculating the azimuth change amount between the heading direction and
Correction coefficient calculation means for calculating a correction coefficient for correcting the direction sensor information based on a difference between the GPS direction change amount and the sensor direction change amount;
A correction coefficient calculation device for an orientation sensor. Further comprising: an azimuth change ratio calculating means for calculating a ratio between the GPS azimuth change amount and the sensor azimuth change amount; and a storage means for storing information on an azimuth change ratio as a calculation result of the azimuth change ratio calculating means. ,
The correction coefficient calculation device for an orientation sensor according to claim 1, wherein the correction coefficient calculation means calculates the correction coefficient based on an average value of all or a part of the plurality of orientation change ratios stored in the storage means.   The azimuth sensor correction coefficient calculation apparatus according to claim 1, wherein the rear region setting unit sequentially sets a plurality of regions having different distances from the neighboring region as the rear region.   The correction coefficient calculating means corrects for the right based on the difference between the GPS azimuth change amount and the sensor azimuth change amount when the azimuth change direction is changed to the right direction or the left direction depending on whether the azimuth change direction is right direction or left direction. The correction coefficient calculation device for the azimuth sensor according to any one of claims 1 to 3, wherein a coefficient and a left correction coefficient are each calculated.   Based on the azimuth sensor information, it further comprises a plurality of azimuth change determination means for judging whether or not there have been a plurality of azimuth changes in different directions between the neighboring area and the rear area, 5. The correction coefficient calculation device for an azimuth sensor according to any one of claims 1 to 4, wherein, when it is determined that there have been azimuth changes, the calculation of the correction coefficient related to the vicinity area and the rear area is omitted. . A self position recognizing device comprising the azimuth sensor correction coefficient computing device according to any one of claims 1 to 5,
The correction coefficient calculation device repeatedly calculates the correction coefficient according to the movement of its own position,
Direction sensor information correction means for correcting the direction sensor information using the latest correction coefficient;
Distance sensor information acquisition means for acquiring distance sensor information from a distance sensor for detecting a moving distance;
Self-position calculation means for calculating the movement locus of the self-position based on the corrected azimuth sensor information and the distance sensor information and recognizing the self-position;
A self-recognition apparatus comprising:   The past direction sensor information is corrected using the latest correction coefficient, and the past movement trajectory of the current position is calculated again based on the corrected past direction sensor information and the past distance sensor information. The self-position recognition apparatus according to claim 6, further comprising self-position correction means for correcting a position recognition result. First determining whether or not the vehicle travels straight within a predetermined vicinity area based on the GPS information from the GPS information acquisition means for acquiring GPS information including position information and traveling direction information based on a signal from a GPS satellite A straight running determination step;
A rear region setting step for setting a rear region separated by a predetermined distance from the neighboring region when the first straight traveling determining step determines that the vehicle has traveled straight in the neighboring region;
Based on the GPS information, a GPS azimuth change calculating step for calculating an azimuth change between a traveling azimuth in the vicinity region and a traveling azimuth in the rear region;
A GPS azimuth change determination step for determining whether there is a azimuth change between the vicinity area and the rear area based on the GPS azimuth change amount;
When it is determined in the GPS azimuth change determination step that there has been a azimuth change, it is determined whether or not the vehicle has traveled straight in both the neighborhood area and the rear area based on the azimuth sensor information from the azimuth sensor. A second straight traveling determination step;
When it is determined by the second straight traveling determination step that the vehicle travels straight in both the vicinity region and the rear region, the traveling direction in the vicinity region and the rear region are determined based on the direction sensor information. Sensor azimuth change amount calculating step for calculating the azimuth change amount between the heading direction and
A correction coefficient calculation step for calculating a correction coefficient for correcting the azimuth sensor information based on a difference between the GPS azimuth change amount and the sensor azimuth change amount;
Correction coefficient calculation program for direction sensor that causes computer to execute. After the sensor azimuth change calculation step, an azimuth change ratio calculation step for calculating a ratio between the GPS azimuth change and the sensor azimuth change, and information on the azimuth change ratio as a calculation result of the azimuth change ratio calculation step Storing in a predetermined storage means, and
The azimuth sensor correction coefficient calculation program according to claim 8, wherein in the correction coefficient calculation step, the correction coefficient is calculated based on an average value of all or a part of the plurality of azimuth change ratios stored in the storage means.   The directional sensor correction coefficient calculation program according to claim 8 or 9, wherein, in the rear region setting step, a plurality of regions having different distances from the neighboring region are sequentially set as the rear region.   In the correction coefficient calculation step, right correction based on the difference between the GPS azimuth change amount and the sensor azimuth change amount when the azimuth change is performed in each direction depending on whether the azimuth change direction is rightward or leftward The directional sensor correction coefficient calculation program according to any one of claims 8 to 10, wherein a coefficient and a left correction coefficient are respectively calculated.   Based on the azimuth sensor information, a plurality of azimuth change determination steps for determining whether or not there have been a plurality of azimuth changes in different directions between the neighboring area and the rear area are further performed, The correction coefficient calculation of the azimuth sensor according to any one of claims 8 to 11, wherein, when it is determined that there have been a plurality of azimuth changes, the calculation of the correction coefficient regarding the area between the neighboring area and the rear area is omitted. program. A self-position recognition program comprising the azimuth sensor correction coefficient calculation program according to any one of claims 8 to 12,
The correction coefficient calculation program repeatedly calculates the correction coefficient according to the movement of its own position,
A direction sensor information correction step for correcting the direction sensor information using the latest correction coefficient;
A self-position calculation step of calculating a movement locus of the own position based on the corrected azimuth sensor information and distance sensor information from a distance sensor for detecting a movement distance, and recognizing the own position;
A self-recognition program that causes a computer to execute.   The past direction sensor information is corrected using the latest correction coefficient, and the past movement trajectory of the current position is calculated again based on the corrected past direction sensor information and the past distance sensor information. The self-position recognition program according to claim 13, further comprising a self-position correction step of correcting a position recognition result.

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