JP2009031154A - Navigation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a navigation device capable of enhancing precision of the shape of a non-registered road by enhancing the accuracy of decision whether it is the non-registered road to be registered. <P>SOLUTION: The navigation device includes a GPS sensor 11 for detecting current position; a reference value modification part 18 for modifying a reference value for evaluating the receiving state of the GPS sensor; a detecting part 14 for detecting the non-registered road, based on position information from the GPS sensor and for generating the non-registered road information, including GPS receiving state data calculated by comparing data relating to the receiving state of the GPS sensor with the reference value concerning a plurality of measuring points of the non-registered road; a determination part 15 for determining whether it is a non-registered road to be registered on map data, based on the GPS receiving state data, included in non-registered road information and the reference value modified with the reference value modifying part; and a registering part 16 for registering the non-registered road detected with the detecting part, when it is determined that it is the non-registered road which should be registered on the map data by the determination part. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a navigation device, and when a moving body moves on an unregistered road that is not registered in map data, it is determined whether the road is an unregistered road to be registered. The present invention relates to a technique for calculating and registering the shape of the image.

  In the conventional navigation apparatus, even if it is determined that the vehicle position does not exist on the road indicated by the map data, the number of GPS satellites that can receive a GPS (Global Positioning System) signal is When it is determined that the reception state is not good, such as when there are less than three, the operation of registering in the map data as road data of a new road is suppressed (see, for example, Patent Document 1).

  Further, in another conventional navigation device, when a road that is not on the map database is passed, it is determined as a road based on the certainty of the vehicle position information at that time (see, for example, Patent Document 2). In this case, the accuracy of the own vehicle position information depends on the number of satellites of the positioning system used for reception or calculation of the own vehicle position or the degree of accuracy degradation of the positioning system (DOP value: accuracy deteriorates due to the geometrical arrangement of the positioning satellites). The index indicating the degree to be performed).

JP 2002-48559 A JP 2003-130656 A

  In the above-described conventional technique, unregistered roads are registered using a predetermined parameter (for example, the number of satellites is four or more) regarding the GPS reception state such as the number of satellites at the time of positioning or the DOP value. Determine whether to do. Therefore, in multipath situations such as when passing through a building street (situation in which multiple paths are affected by reflected waves before the transmitted radio wave is received by the other party), the number of satellites or the DOP value is accurate. Therefore, there is a problem that the GPS reception state at the time of detecting an unregistered road cannot be accurately grasped.

  Also, if there is a building street or a short tunnel locally in the middle of an unregistered road, the reception condition is poor in some areas even though the reception condition is good in the majority of unregistered roads. There is a problem that unregistered roads cannot be detected and registered. In addition, the shape of the unregistered road in the section where the GPS reception status is bad becomes unstable (disturbed) due to the influence of the bad reception status. There is a problem that the accuracy of judgment and the accuracy of the shape of unregistered roads deteriorate.

  The present invention has been made to solve the above-described problems, and its task is to determine whether an unregistered road to be registered when moving on an unregistered road that is not registered in the map data. It is an object of the present invention to provide a navigation device that can improve the accuracy of the shape of an unregistered road by increasing the accuracy of the road.

  In order to solve the above problems, a navigation device according to the present invention detects a current position and outputs it as position information, and a reference value changing unit that changes a reference value for evaluating the reception state of the GPS sensor And an unregistered road that is not registered in the map data is detected based on position information from the GPS sensor, and a plurality of measurement points of the detected unregistered road are received by the data relating to the reception state of the GPS sensor and the reference value changing unit. A detection unit that generates unregistered road information including GPS reception state data calculated by comparing the changed reference value, and GPS reception state data and reference value included in the unregistered road information generated by the detection unit Based on the reference value changed by the change unit, a determination unit that determines whether the road is an unregistered road to be registered in the map data, and the determination unit If it is determined that the unregistered road to be registered in, and a registration unit for registering an unregistered road detected by the detection unit in the map data.

  According to the navigation device of the present invention, the reference value changing unit that changes the reference value for evaluating the reception state of the GPS sensor is provided, and unregistered roads that are not registered in the map data are used as position information from the GPS sensor. This is an unregistered road that should be registered in the map data by comparing the data related to the reception state of the GPS sensor with the reference value changed by the reference value changing unit at a plurality of measurement points of the detected unregistered road. Since it is configured to determine whether or not it is an unregistered road to be registered by changing the reference value as appropriate, the accuracy of the shape of the unregistered road can be increased as a result. Can be raised.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Embodiment 1 FIG.
1 is a block diagram showing a configuration of a navigation apparatus according to Embodiment 1 of the present invention. The navigation device includes a GPS sensor 11, a direction sensor 12, a speed sensor 13, a detection unit 14, a determination unit 15, a registration unit 16, a map data storage unit 17, a reference value change unit 18, and a communication unit 19.

  The GPS sensor 11 detects the current position (latitude, longitude, altitude, etc.) of the vehicle from a signal obtained by receiving radio waves from a GPS satellite. The current position detected by the GPS sensor 11 is sent to the detection unit 14 as position information. The direction sensor 12 is composed of, for example, a gyro sensor and detects the traveling direction of the vehicle. The traveling direction detected by the direction sensor 12 is sent to the detection unit 14 as direction information. The speed sensor 13 is composed of, for example, a speedometer and detects the traveling speed of the vehicle. The traveling speed detected by the speed sensor 13 is sent to the detector 14 as speed information.

  The detection unit 14 detects the vehicle position based on the position information sent from the GPS sensor 11, the direction information sent from the direction sensor 12, and the speed information sent from the speed sensor 13. Using the vehicle position, a departure point from the registered road (start point of the unregistered road) and a return point to the registered road (end point of the unregistered road) are detected.

  The detection unit 14 also includes position information sent from the GPS sensor 11, direction information sent from the direction sensor 12, and speed sensor at a plurality of measurement points between the start point and end point of the detected unregistered road. 13 based on the speed information sent from 13 and the reference value A (details will be described later) sent from the reference value changing unit 18, the coordinate data of each measurement point and the GPS reception status data at each measurement point The unregistered road information including is generated.

  For coordinate data, for example, using a Kalman filter, the position information sent from the GPS sensor 11, the direction information sent from the direction sensor 12, and the speed information sent from the speed sensor 13 are considered in a composite manner. Calculated. Note that the coordinate data is calculated using only the position information sent from the GPS sensor 11, or the direction information sent from the direction sensor 12 without using the position information sent from the GPS sensor 11. It may be configured to calculate by so-called autonomous navigation using speed information sent from the speed sensor 13.

  The GPS reception status data includes “data related to reception status” such as the number of GPS satellites or DOP values that the GPS sensor 11 was able to receive GPS signals at the time of position calculation, and “reference value A related to reception status” ( For example, in the case of the number of GPS satellites, it is calculated by comparing with 4). Specifically, the reference value A is used as a threshold value, and a value indicating the result of comparing the magnitude relationship between the data related to the reception state and the reference value A is calculated. For example, when evaluating by the number of GPS satellites, if the number of GPS satellites is greater than four, the reception state is good, and the evaluation result value “1” is assumed. Calculated. In addition, it can also comprise so that the ratio of the data regarding a receiving state and the reference value A may be used as GPS receiving state data.

  The determination unit 15 uses the unregistered road information generated by the detection unit 14 to determine whether the road is an unregistered road to be registered. Specifically, for example, the ratio of the measurement points (coordinates) evaluated as being good by the GPS reception state data included in the unregistered road information to the entire unregistered road information, that is, “the reception state is good. By comparing “number of measurement points / number of all measurement points” with “reference value B regarding the reception state”, it is determined whether the road is an unregistered road to be registered. For example, when the reference value B is 50%, if there are more than half of the measurement points that are determined to be good by GPS reception status data for the entire unregistered road, It is judged that there is. More generally, if the average value of the GPS reception state data is greater than or equal to the reference value B, it can be determined that the road is an unregistered road to be registered. When the determination unit 15 determines that the road is an unregistered road to be registered, the determination unit 15 instructs the registration unit 16 to register the unregistered road.

  As described above, by evaluating the GPS reception state data at each measurement point with the entire unregistered road information (for example, an average value, etc.) and determining whether the road is to be registered, it is determined locally in a tunnel, for example. Even if the reception state is poor, if the reception state outside the tunnel section is good, it can be determined that the road is not registered.

  Alternatively, the GPS reception state data in the vicinity of the start point and end point of the unregistered road may be weighted, and then an average value may be calculated and evaluated. This configuration is effective when it is desired to perform detection focusing on deviation from the registered road and return.

  The registration unit 16 stores the unregistered road generated using the unregistered road information generated by the detection unit 14 in the map data storage unit 17 when there is an instruction to register from the determination unit 15. To the map data. The map data storage unit 17 stores map data. The map data stored in the map data storage unit 17 is updated from the registration unit 16 as described above.

  The reference value changing unit 18 determines the reference value A related to the reception state used in the detection unit 14 and the reference value B related to the reception state used in the determination unit 15 according to the characteristics of the area corresponding to the coordinate data of each measurement point. To change. In the following, the case where the number of GPS satellites is used as the reference value A and the reference value B will be described. However, the DOP value may be used as the reference value A and the reference value B. The communication unit 19 controls communication between the navigation device (more specifically, the reference value changing unit 18) and the center 1.

  More specifically, the reference value changing unit 18 changes the reference value A according to the regional characteristics such as the land use classification indicated by the map data read from the map data storage unit 17. For example, in a multipath situation such as when passing through a building street, the number of GPS satellites that can actually be used for position calculation by the GPS sensor 11 is reduced due to the influence of buildings, steel towers, bridges, and the like. There are cases where the number of GPS satellites to be measured increases (the DOP value decreases), and there is a situation in which the reception state of the GPS sensor 11 cannot be accurately grasped. In such a case, the reference value A is changed in advance so that the reference value A of a region where the reception state is expected to be deteriorated due to the influence of a building or the like becomes strict (in the case of the number of GPS satellites).

  In this way, by changing the criteria for comparative evaluation in a specific area where it is estimated that the reception status cannot be measured accurately, the results of comparative evaluation will be unduly good due to the effects of multipath, etc. Can be prevented. Especially in Japan and other areas where the building height limit and the occupancy rate are determined in detail according to the use area defined by the City Planning Act, the correlation between land use classification and reception status is high, The accuracy of the GPS reception status data can be greatly increased by changing the reference value according to the region.

  Further, the reference value changing unit 18 changes the reference value B related to the reception state used in the determination unit 15 according to the characteristics of the region corresponding to the entire unregistered road. For example, according to the regional characteristics such as the land use classification indicated by the map data read from the map data storage unit 17, the reference value in the region where the possibility of newly establishing a road is low due to the regional characteristics is changed rigorously. deep. This can prevent an unregistered road that should not be registered from being erroneously determined as an unregistered road that should be registered.

  Further, the reference value changing unit 18 receives a reference value changing instruction sent from the external center 1 via the communication unit 19, and according to the region or time included in the received reference value changing instruction. The reference value A related to the reception state used in the detection unit 14 or the reference value B related to the reception state used in the determination unit 15 may be changed. In this case, before receiving the reference value change instruction from the center 1, information regarding the position of the moving body can be transmitted to the center 1 in advance. According to this configuration, it is possible to limit the area range where the reference value change instruction is received, and thus it is possible to suppress the traffic.

  For example, when it is determined that a road is scheduled to open, an unregistered road to be registered should be erroneously determined by sending an instruction from the center 1 to set a reference value for the area scheduled to be opened low. Probability can be reduced. In addition, when a place that is not originally a road (such as a circuit) is temporarily opened to hold an event or the like, a road that should not be registered is sent by sending an instruction to set a high reference value from the center 1. It is possible to prevent erroneous determination as an unregistered road to be registered.

  In addition, when an instruction from the user 2 is made, the reference value changing unit 18 sets the reference value A related to the reception state in the detection unit 14 or the reference value B related to the reception state in the determination unit 15 according to the region or time. Can be configured to change. For example, the user can make a judgment that reflects the user's intention by changing the reference value of an area that is not desired to be registered high or by changing the reference value for an area that is desired to be registered such as a road near the home to a low value. It is possible to improve user convenience.

  Various methods can be used as a method for detecting the start point and the end point of the unregistered road in the detection unit 14 described above. For example, unregistered by performing map matching on roads registered in the map data stored in the map data storage unit 17 and comparing the coordinate data or shape of the registered road with the coordinate data at the time of movement. It can be configured to detect the start and end points of the road.

  FIG. 2 is a conceptual diagram showing an image when the navigation device according to Embodiment 1 of the present invention travels on an unregistered road. A point that deviates from the registered road is designated as the “start point of the unregistered road”, a point that has returned to the registered road is designated as the “end point of the unregistered road”, and the interval between the start point and end point of these unregistered roads "Road" is detected and registered.

  FIG. 3 is a flowchart showing the operation of the navigation device according to the first embodiment of the present invention, centering on the registration processing of unregistered roads performed when traveling as shown in FIG.

  In the unregistered road registration process, first, a start point detection process is performed (step ST11). That is, the detection unit 14 detects the vehicle position based on the position information sent from the GPS sensor 11, the direction information sent from the direction sensor 12, and the speed information from the speed sensor 13, and the detected vehicle The departure point from the registered road is detected using the position. This detected departure point is set as the starting point of the unregistered road.

  Next, end point detection processing is performed (step ST12). That is, the detection unit 14 detects the vehicle position based on the position information sent from the GPS sensor 11, the direction information sent from the direction sensor 12, and the speed information from the speed sensor 13, and the detected vehicle The return point to the registered road is detected using the position. This detected return point is the end point of the unregistered road.

  Next, unregistered road information generation processing is performed (step ST13). That is, the detection unit 14 receives position information sent from the GPS sensor 11 at a plurality of measurement points between the start point of the unregistered road detected in step ST11 and the end point of the unregistered road detected in step ST12. The coordinate data of each measurement point based on the direction information sent from the direction sensor 12 and the speed information sent from the speed sensor 13 and the reference value A related to the reception state sent from the reference value changing unit 18. And unregistered road information including GPS reception state data at each measurement point is generated and sent to the determination unit 15.

  Next, it is checked whether or not the road is an unregistered road to be registered (step ST14). That is, the determination part 15 determines whether it is an unregistered road which should be registered using the unregistered road information produced | generated by step ST13. If it is determined in step ST14 that the road is not an unregistered road, the sequence returns to step ST11 and the above-described processing is repeated.

  On the other hand, if it is determined in step ST14 that the road is an unregistered road, registration processing is then performed (step ST15). That is, the registration unit 16 registers an unregistered road in the map data using the unregistered road information. Thereafter, the sequence returns to step ST11 and the above-described processing is repeated.

  In the navigation device according to the first embodiment described above, when the determination unit 15 determines that the road is an unregistered road to be registered, the determination unit 15 sends the unregistered road information to the registration unit 16 and automatically registers it. However, as illustrated in FIG. 4, when the determination unit 15 determines that the road is an unregistered road to be registered, the determination unit 15 transmits unregistered road information to the center 1 via the communication unit 19. Map data change information is created in the center 1 and sent to the registration unit 16 via the communication unit 19, and the registration unit 16 is configured to register unregistered roads in the map data using the received change information. Can do. Further, when the unregistered road information is received at the center 1, it can be determined again whether the road is an unregistered road to be registered at the center 1.

Embodiment 2. FIG.
The navigation device according to Embodiment 1 described above is configured to change the reference value related to the reception state in the detection unit 14 and the determination unit 15 using the land use classification indicated by the map data. The navigation device according to aspect 2 estimates the GPS reception state using the magnitude of the coordinate error for each measurement point, and the reference value A for the reception state in the detection unit 14 and the reference value B for the reception state in the determination unit 15. Is to be changed.

    FIG. 5 is a block diagram showing a configuration of the navigation apparatus according to Embodiment 2 of the present invention. This navigation device is configured by removing the communication unit 19 from the navigation device according to the first embodiment, adding a shape comparison unit 20, and further changing the function of the reference value changing unit 18.

  The shape comparison unit 20 includes coordinates calculated using position information sent from the GPS sensor 11 and a direction sensor at a plurality of measurement points between the start point and end point of the unregistered road detected by the detection unit 14. An error in the shape of the unregistered road is calculated by calculating an error (distance, etc.) from the coordinates calculated using the direction information sent from 12 and the speed information sent from the speed sensor 13. The error in the shape of the unregistered road calculated by the shape comparison unit 20 is sent to the reference value changing unit 18.

  The reference changing unit 18 estimates the GPS reception state using the unregistered road shape error sent from the shape comparison unit 20, that is, the coordinate error for each measurement point, and is used in the detection unit 14. The reference value A regarding the reception state is changed. In addition, the reference changing unit 18 is a reference value related to the reception state used in the determining unit 15 according to the magnitude of the coordinate error of the entire unregistered road (such as the sum and average value of the coordinate errors for each measurement point). Change B.

  6 shows coordinates calculated using position information sent from the GPS sensor 11, coordinates calculated using direction information sent from the direction sensor 12, and speed information sent from the speed sensor 13. It is a conceptual diagram which shows the difference. For example, when a building street, a steel tower, a bridge, or the like exists in an unregistered road section, coordinates calculated using position information sent from the GPS sensor 11 may become unstable due to the influence of a multipath or the like. . Even in such a case, coordinates calculated using the direction information sent from the direction sensor 12 and the speed information sent from the speed sensor 13 that are not affected by the reception state of the GPS sensor 11, and the GPS As a result of comparing the coordinates calculated using the position information sent from the sensor 11, if the error between the two is large, it can be estimated that the reception state is not good even if the number of GPS satellites is large. By utilizing this property, for example, when the coordinate error is large, the reference value is changed strictly (in the case of the number of GPS satellites).

  In this way, when it is estimated that the reception status cannot be measured accurately, by changing the criteria for comparative evaluation to be stricter, it is possible to prevent the results of comparative evaluation from becoming unreasonably good due to the effects of multipath, etc. can do.

  Further, before calculating the coordinate error, the coordinates calculated using the position information sent from the GPS sensor 11 near the start point and end point of the unregistered road in which the GPS reception state is good, and the direction sensor 12 The direction information sent from the direction sensor 12 and the speed sent from the speed sensor 13 so that the coordinates calculated using the direction information sent from the speed information sent from the speed sensor 13 coincide with each other. The coordinates calculated using the information can be configured to translate, rotate, and expand / contract (affine transformation). With this configuration, it is possible to remove the error in the coordinates calculated using the azimuth information sent from the azimuth sensor 12 and the velocity information sent from the speed sensor 13, which are likely to accumulate errors due to integration.

Embodiment 3 FIG.
The navigation device according to Embodiment 3 of the present invention calculates the coordinate data generated by the detection unit 14 by the following method in order to increase the accuracy of the coordinate data representing the movement trajectory included in the unregistered road information. It is a thing.

In the following, a description will be given using a discrete time system with a time interval ΔT, and the following variables will be defined. However, the direction is based on the horizontal direction. FIG. 7 is a diagram showing a coordinate system related to a calculation method of coordinate data.

Further, it is assumed that the discrete time interval (ΔT) is sufficiently short and the following assumptions hold.

At this time, the following relationship is established between the position at time k + 1 and the position at time k. However, the measurement interval (500 [ms]) of the movement distance (Δd) and the turning angle (Δθ) is sufficiently shorter than the speed of each change, and is equal between the measurement intervals (500 [ms]). It is assumed that fast circular motion can be assumed.

ただし、次の行列およびベクトルを定義している。ただし、ＧＰＳセンサ１１から送られてくる位置情報からｘ、ｙ座標に加え方位（θ）も計測できる場合は、上記行列Ｃは４×４の単位行列となる。以下においては、ＧＰＳセンサ１１から送られてくる位置情報に基づき、ｘ、ｙ座標が算出できる場合について説明する。

When the x coordinate and the y coordinate among the state variables can be calculated from position information sent from the GPS sensor 11, a model (state equation) for the Kalman filter is expressed by the following equation.

However, the following matrix and vector are defined. However, when the azimuth (θ) can be measured from the position information sent from the GPS sensor 11 in addition to the x and y coordinates, the matrix C is a 4 × 4 unit matrix. In the following, a case where x and y coordinates can be calculated based on position information sent from the GPS sensor 11 will be described.

An algorithm for estimating a state variable using a Kalman filter with respect to the above model is expressed by the following equation (K (k) is called a Kalman gain, and the correction amount by the observed value y (k) is adjusted. Take a role).

  With the above algorithm, the initial value of the matrix P and the initial value of the state variable are given, and the above equation is updated with the measured value at each time point, whereby an estimated value related to the position can be obtained. Specifically, the x and y coordinates (x (k), y (k)) calculated from the position information sent from the GPS sensor 11 at time k, and the azimuth information and the velocity sensor 13 from the azimuth sensor 12. Using Δd (k) and Δθ (k) obtained from the speed information sent, an estimated value related to the position at time k + 1 can be obtained.

  Further, by changing the covariance matrix (R (k)) regarding the observation error at each time according to the reference value A regarding the GPS reception state data in the unregistered road information or the reception state at the time of GPS reception state data calculation, The correction amount by the Kalman gain (K (k)) expressed by the above equation is appropriately adjusted. For example, when it is estimated that the observation error related to the GPS sensor 11 is large from the GPS reception state data or the reference value related to the reception state when calculating the GPS reception state data, the component of the associated covariance matrix (R (k)) is increased. Thus, the Kalman gain (K (k)) can be reduced, and the correction amount based on the position information from the GPS sensor 11 can be kept small.

  As described above, the coordinates obtained from the position information sent from the GPS sensor 11 and the direction information sent from the direction sensor 12 and the speed information sent from the speed sensor 13 are combined by a Kalman filter, By adjusting the position correction gain (Kalman gain) in the Kalman filter according to the reference value related to the reception state that becomes the reference of the observation error of the GPS sensor 11, the radio wave from the GPS satellite is interrupted and the reception state is poor. However, highly accurate coordinate data can be calculated without continuously destabilizing, and the calculation accuracy of coordinate data can be improved.

  Thus, by improving the calculation accuracy of the movement trajectory and generating the coordinate data representing the movement trajectory of the unregistered road information output by the detection unit 14, the coordinate accuracy when the unregistered road is registered can be improved. Convenience and safety when traveling on an unregistered road after registration can be improved.

It is a block diagram which shows the structure of the navigation apparatus which concerns on Embodiment 1 of this invention. It is a conceptual diagram which shows an image when the navigation apparatus which concerns on Embodiment 1 of this invention drive | works the unregistered road. It is a flowchart which mainly shows operation | movement of the navigation apparatus which concerns on Embodiment 1 of this invention centering on the registration process of the unregistered road in the case of drive | working as shown in FIG. It is a block diagram which shows the structure of the modification of the navigation apparatus which concerns on Embodiment 1 of this invention. It is a block diagram which shows the structure of the navigation apparatus which concerns on Embodiment 2 of this invention. In the navigation apparatus which concerns on Embodiment 2 of this invention, it is a conceptual diagram which shows the difference between the coordinate by a GPS sensor, and the coordinate by a direction sensor and a speed sensor. It is a figure which shows the coordinate system regarding the calculation method of the coordinate data in the navigation apparatus which concerns on Embodiment 3 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Center, 2 users, 11 GPS sensor, 12 Direction sensor, 13 Speed sensor, 14 Detection part, 15 Judgment part, 16 Registration part, 17 Map data storage part, 18 Reference value change part, 19 Communication part, 20 Shape comparison part .

Claims (7)

A GPS sensor that detects the current position and outputs it as position information;
A reference value changing unit for changing a reference value for evaluating the reception state of the GPS sensor;
An unregistered road that is not registered in the map data is detected based on position information from the GPS sensor, and data regarding the reception state of the GPS sensor and the reference value changing unit for a plurality of measurement points of the detected unregistered road A detection unit that generates unregistered road information including GPS reception state data calculated by comparing with the reference value changed in
Based on the GPS reception state data included in the unregistered road information generated by the detection unit and the reference value changed by the reference value changing unit, it is determined whether the road is an unregistered road to be registered in the map data. A determination unit to perform,
A navigation apparatus comprising: a registration unit that registers an unregistered road detected by the detection unit in map data when the determination unit determines that the road is an unregistered road to be registered in map data. The navigation apparatus according to claim 1, wherein the reference value changing unit changes the reference value used by the detecting unit in accordance with the characteristics of the area indicated by the map data. The navigation device according to claim 1, wherein the reference value changing unit changes a reference value used by the detecting unit in response to an instruction from the outside. The navigation apparatus according to claim 1, wherein the reference value changing unit changes a reference value used by the detecting unit in response to an instruction from a user. The navigation according to any one of claims 1 to 4, wherein the reference value changing unit changes the reference value used by the determination unit according to the characteristics of the region corresponding to the entire unregistered road. apparatus. The shape of the unregistered road calculated using the position information from the GPS sensor is compared with the shape of the unregistered road calculated using the direction information from the direction sensor and the speed information from the speed sensor. A shape comparison unit for calculating the shape error of
6. The reference value changing unit changes a reference value used by a detection unit or a determination unit based on an error in the shape of an unregistered road calculated by the shape comparison unit. The navigation device according to any one of the above. The detection unit calculates coordinates by combining the coordinates obtained from the position information from the GPS sensor, the direction information from the direction sensor, and the speed information from the speed sensor using a Kalman filter, and evaluates the reception state of the GPS sensor. The navigation device according to any one of claims 1 to 6, wherein a position correction gain in the Kalman filter is adjusted according to a reference value.

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