JP2007263844A - Position detector, method, program and recording medium thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a position detector for determining the position of a vehicle precisely. <P>SOLUTION: A map matching position calculating section 221 calculates a map matching position based on positioning results by a GPS receiving unit 170 and detection results by a travel sensor unit, while estimating that a vehicle travels on a road in map information 121. A sensor position calculating section 222 calculates a sensor position from the detection results by the travel sensor unit. The sensor position is initialized by a sensor position initializing section 223 when the positioning results or the map matching position can be determined highly precise. Thus, when the precision of the sensor position with initialization properly performed is evaluated to be high by a sensor position precision evaluating section 224 with a certain value or more of difference between the sensor position and the map mapping position, a map matching position correcting section 225 corrects the map mapping position by taking the sensor position as the reference position. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a position detection device, a position detection method, a position detection program, and a recording medium on which the position detection program is recorded.

  2. Description of the Related Art Conventionally, navigation devices that are mounted on a moving body such as a vehicle, search for a recommended route to a destination, and guide and guide movement along the recommended route have been widely used. In such a navigation device, a map matching position obtained by matching the current position of the moving object on the map is obtained as the position of the moving object and used for the navigation process.

  In the map matching process for obtaining the map matching position, it is assumed that the moving body moves along the moving path in the map information. For example, the moving body by a moving state sensor such as a speed sensor or an angular velocity sensor mounted on the moving body. The map matching position is calculated using the moving distance and moving direction obtained from the detection results such as the speed and direction change amount (see Patent Document 1). In the technique of the conventional example 1, since the map matching position is calculated on the assumption that the moving body moves along the moving path in the map information, there is an error in the moving path data in the map information, or the moving path is under construction. When a detour is temporarily provided due to the middle or the like, the map matching position deviates from the actual position of the moving body. For this reason, for example, a technique for appropriately correcting the position by referring to a positioning result by GPS positioning based on a received radio wave from a GPS (Global Positioning System) satellite has been proposed (see Patent Document 2).

JP-A-8-334346 Japanese Patent Laid-Open No. 9-311044

  When the map matching position is calculated by performing correction using the GPS positioning result as described above, the accuracy of the map matching position greatly depends on the accuracy of the GPS positioning result. It is difficult to say that the accuracy of the GPS positioning result is very high as the accuracy of the map matching position required in the navigation process. Further, with the advancement of navigation processing in recent years, it has been required to further improve the accuracy required for the map matching position. Responding to such a request is one of the problems to be solved by the present invention.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a position detection device and a position detection method that can accurately determine the position of a moving body.

  The invention according to claim 1 is a positioning means for positioning the position of the moving body based on information received from the outside of the moving body; and a sensor mounted on the moving body and detecting a moving state of the moving body And a sensor position calculating means for calculating a sensor position estimated as a current position of the moving body based on a detection result by the sensor means; on the basis of a positioning result by the positioning means and a detection result by the sensor means, A map matching position calculating unit that calculates a map matching position by performing matching on a map; an evaluation unit that evaluates the accuracy of the sensor position; and the evaluation unit evaluates that the accuracy of the sensor position is high; and When the map matching position and the sensor position are separated from each other by a predetermined distance or more, the map matching is based on the sensor position. A position detecting device characterized by comprising a; and correction means for correcting the location.

  According to a thirteenth aspect of the present invention, there is provided a positioning step of positioning the position of the moving body based on information received from the outside of the moving body; and a movement status of the moving body by sensor means mounted on the moving body. A movement status detection step for detecting; a sensor position calculation step for calculating a sensor position based on a detection result in the movement status detection step; and a map on the basis of a positioning result in the positioning step and a detection result in the movement status detection step. A map matching position calculating step for calculating a map matching position by performing a matching to; an evaluation step for evaluating the accuracy of the sensor position; and determining whether or not the accuracy of the sensor position is evaluated to be high in the evaluation step A first determination step, and when the determination result in the first determination step is affirmative, the map matching position and the A second determination step for determining whether or not the sensor position is more than a predetermined distance; and if the determination result in the second determination step is affirmative, the map matching position is determined based on the sensor position. A position detecting method comprising: a correcting step for correcting.

  According to a fourteenth aspect of the present invention, there is provided a position detection program that causes a calculation means to execute the position detection method according to the thirteenth aspect.

  According to a fifteenth aspect of the present invention, there is provided a recording medium in which the position detection program according to the fourteenth aspect is recorded so as to be readable by the calculation means.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. In the present embodiment, a navigation device mounted on a vehicle and having a function of a position detection device will be described as an example.

[Constitution]
FIG. 1 is a block diagram showing the configuration of the navigation device 100 according to this embodiment. As shown in FIG. 1, the navigation device 100 includes a control unit 110 and a storage device 120. The navigation apparatus 100 includes a sound output unit 130, a display unit 140, an operation input unit 150, a travel sensor unit 160 as sensor means, and a GPS (Global Positioning System) reception unit 170 as positioning means. ing. Elements 120 to 170 other than the control unit 110 are connected to the control unit 110, respectively.

  The control unit 110 performs various processes while controlling the entire navigation device 100. The control unit 110 includes a navigation processing unit 200 that performs processing related to navigation.

  The navigation processing unit 200 includes a sensor data processing unit 210, a map matching unit 220, and a route search unit 230. The navigation processing unit 200 configured as described above provides navigation information to the user by using the above-described components 130 to 170 while accessing the storage device 120. That is, the navigation processing unit 200 stores the command input result from the operation input unit 150 related to the navigation processing, the detection result by the travel sensor unit 160, the positioning result in the GPS receiving unit 170, and the like in the storage device 120. The stored navigation data is read appropriately. The navigation processing unit 200 (a) displays a map of a region designated by the user on the display device 140, and (b) indicates where the vehicle is located on the map and in which direction. Map matching to calculate whether you are heading, (c) Search for a recommended route from the current position of the vehicle to the destination location specified by the user, (d) Drive to the destination along the set route Sometimes, guidance is displayed on the display device of the display unit 140, or voice guidance is output from the sound output unit 130 to give route guidance in order to accurately advise the estimated time of arrival at the destination and the direction to travel. Etc.

  The sensor data processing unit 210 calculates travel state information of a travel distance and a travel direction (which may include a vehicle tilt angle (tilt direction)) based on the detection result by the travel sensor unit 160. The sensor data processing unit 210 reports the calculated traveling state information to the map matching unit 220.

  In addition, the sensor data processing unit 210 performs learning for processing the detection result by the travel sensor unit 160. Information about whether or not learning is in progress is reported from the sensor data processing unit 210 to the map matching unit 220.

  In addition, the sensor data processing unit 210 appropriately corrects the detection result by the travel sensor unit 160 based on the report result from the GPS receiving unit 170 and the like.

  The map matching unit 220 has the function (b) described above. Details of the map matching unit 220 will be described later.

  The route search unit 230 has the function (c) described above. This function is executed in response to a route search command specifying a destination by the user. In addition, the route search unit 230 performs route search in response to the reroute search command.

  The storage device 120 includes a hard disk device or the like. The storage device 120 stores various data necessary for the operation of the navigation device 100 including the map information 121. The control unit 110 can access a storage area of the storage device 120 and can read data from the storage area.

  The sound output unit 130 (i) a digital to analog converter that converts digital audio data received from the control unit 110 into an analog signal, and (ii) amplifies the analog signal output from the DA converter. And (iii) a speaker that converts the amplified analog signal into sound. Under the control of the control unit 110, the sound output unit 130 outputs guidance voice, music, etc., such as the traveling direction of the vehicle, the traveling situation, and the traffic situation.

  The display unit 140 displays (i) a display device such as a liquid crystal display panel, an organic EL (Electro Luminescence) panel, a PDP (Plasma Display Panel), and (ii) display control data sent from the control unit 110. A display controller such as a graphic renderer for controlling the entire unit 140 and (iii) a display image memory for storing display image data are included. The display unit 140 displays map information, route information, operation guidance information, and the like under the control of the control unit 110.

  The operation input unit 150 is configured by a key unit provided in the main body of the navigation device 100 or a remote input device including the key unit. Here, a touch panel provided in the display unit 140 can be used as the key part provided in the main body. In addition, it can replace with the structure which has a key part, and the structure which inputs voice can also be employ | adopted.

  The travel sensor unit 160 includes (i) a speed sensor 161 that detects the moving speed of the vehicle, (ii) an angular speed sensor 162 that detects the angular speed of the vehicle, and (iii) an acceleration sensor that detects acceleration acting on the vehicle. 163. Here, the speed sensor 161 detects, for example, a pulse signal or a voltage value output by a wheel or wheel rotation. The angular velocity sensor 162 is configured as a gyro sensor, for example, and detects the angular velocity. Further, the acceleration sensor 163 detects, for example, three-dimensional acceleration. Such a detection result is sent from the traveling sensor unit 160 to the control unit 110.

  The learning for processing the detection result by the travel sensor unit 160 described above includes the travel distance per pulse of the vehicle speed pulse, the sensitivity / temperature characteristics / individual variation of the angular velocity sensor 162, and the sensitivity / temperature characteristics of the acceleration sensor 163.・ Individual variation and the like can be mentioned.

  The GPS receiving unit 170 calculates the current position of the vehicle (hereinafter referred to as “positioning result”) based on reception results of radio waves from a plurality of GPS satellites, and reports it to the control unit 110 together with its accuracy information. Further, the GPS receiving unit 170 detects the speed and traveling direction of the vehicle based on the wavelength change due to the Doppler effect of the radio wave from the GPS satellite, and reports it to the control unit 110. The GPS receiving unit 170 measures the current time based on the time transmitted from the GPS satellite and reports it to the control unit 110.

  In areas where the GPS receiving unit 170 cannot receive radio waves from GPS satellites, the GPS receiving unit 170 cannot obtain positioning results and the like. The number of GPS satellites that can be captured when a vehicle is present in an area where the radio wave from the GPS satellite is weak, or the vehicle is present in an area where a multipath is generated due to the presence of a high-rise building or the like. When there are few, etc., the precision of the positioning result etc. by the GPS receiving unit 170 will become low.

  As shown in FIG. 2, the map matching unit 220 includes a map matching position calculation unit 221 as a map matching position calculation unit, a sensor position calculation unit 222 as a sensor position calculation unit, and a sensor as an initialization unit. A position initialization unit 223. The map matching unit 220 includes a sensor position accuracy evaluation unit 224 as an evaluation unit and a map matching position correction unit 225 as a correction unit.

  The map matching position calculation unit 221 calculates the pre-matching position based on the previous map matching position, the traveling state information calculated by the sensor data processing unit 210, and the report result from the GPS receiving unit 170. Then, the map matching position calculation unit 221 calculates the map matching position by calculating the most probable position using the calculated pre-matching position as the vehicle position on the map using the map information 121. That is, the map matching position calculation unit 221 calculates the map matching position on the assumption that the vehicle travels on the road represented by the road data in the map information 121.

  The map matching position calculation unit 221 reports the map matching position (post-matching position) and the pre-matching position to the sensor position initialization unit 223. Further, the map matching position calculation unit 221 reports the map matching position to the map matching position correction unit 225.

  The sensor position calculation unit 222 calculates the estimated vehicle position based on the previous sensor position and the traveling state information calculated by the sensor data processing unit 210. When the sensor position calculation unit 222 calculates the sensor position, the map information 121 is not considered. The calculated sensor position is reported to the map matching position correction unit 225. In addition, the fact that the sensor position has been calculated is reported to the sensor position accuracy evaluation unit 224.

  When the sensor position initialization unit 223 determines that the accuracy of the map matching position is high, the sensor position initialization unit 223 initializes the sensor position with reference to the map matching position. The sensor position initialization unit 223 determines that the accuracy of the map matching position is high when the map matching position exists in the vicinity of the positioning result obtained by the GPS receiving unit 170. Here, the distance between the map matching position and the positioning result for which it can be said that “the map matching position exists in the vicinity of the positioning result by the GPS receiving unit 170” is based on the results of experiments, simulations, and the like in advance. Determined.

  In addition, the sensor position initialization unit 223 performs a positioning result obtained by the GPS receiving unit 170, a calculation result obtained by the sensor data processing unit 210, and a calculation result obtained by the sensor data processing unit 210 in a travel in which the road direction changes at a predetermined angle or more in the map information 121 such as when turning an intersection If the distance error between the pre-matching position obtained based on the previous map matching position and the post-matching position obtained by matching on the map does not exceed the predetermined value, the accuracy of the map matching position is high. to decide. Here, the “predetermined angle” and the “predetermined value” are determined in advance based on results of experiments and simulations.

For example, when the predetermined angle is less than 90 degrees and the predetermined value is d ₀ , an intersection having a road intersection angle of approximately 90 degrees as shown in FIG. 3 (in FIG. 3, a road near the intersection based on map data) Suppose the vehicle turns right in the situation shown). In this case, the pre-matching position after the right turn newly obtained based on the positioning result by the GPS receiving unit 170, the calculation result by the sensor data processing unit 210, and the previous map matching position (triangle that is internally hatched). When (▲) is a position on the map shown in FIG. 3, the map matching position calculation unit 221 performs matching on the map, and a post-matching position (Δ) is obtained. In this case, if the position error between the pre-matching position and the post-matching position is d, if d <d ₀ , the sensor position initialization unit 223 determines that the accuracy of the map matching position is high. On the other hand, if d ≧ d ₀ , the sensor position initialization unit 223 determines that the accuracy of the map matching position is low. Even when the intersection shown in FIG. 3 is turned to the left, a determination regarding the accuracy of the map matching position is made in the same manner as in the case of the right turn.

  When initializing the sensor position, the sensor position initialization unit 223 initializes the sensor position to a position according to the attribute of the road on the road where the map matching position exists. For example, when the road attribute is one-way, the sensor position is initialized to the map matching position. When the road attribute is both traffic, the road data indicates the center of the road. For example, in a country where a vehicle such as Japan is running on the left side, as shown in FIG. The sensor position is initialized to a position separated from the map matching position by half of the road width on the left side in the vertical direction. Further, in a country where a vehicle such as the United States travels on the right side, the sensor position is initialized to a position separated from the map matching position by half the width of the road on the right side in the vertical direction of the road direction.

  Here, when the width data is present in the map information 121 as the road data, the sensor position initialization unit 223 uses the width data to initialize the sensor position. On the other hand, when the width data does not exist in the map information 121, the sensor position is initialized using the normal road width. Further, when the lane in which the vehicle is traveling (the traveling lane) can be recognized, the sensor position may be initialized according to the position of the traveling lane.

  In addition, when the sensor position initialization unit 223 determines that the accuracy of the positioning result by the GPS receiving unit 170 is high, the sensor position initialization unit 223 initializes the sensor position based on the positioning result. Here, when the GPS positioning is performed without SA (Selective Availability) and without multipath, and the PDOP (Positional Dilution Of Precision) is low, the accuracy of the positioning result is high. Judged to be high. And the sensor position initialization part 223 initializes a sensor position to the position of the positioning result by the GPS receiving unit 170.

  The sensor position initialized as described above is reported to the sensor position calculation unit 222.

  Upon receiving a report that the sensor position has been calculated from the sensor position calculation unit 222, the sensor position accuracy evaluation unit 224 evaluates the accuracy of the sensor position calculated by the sensor position calculation unit 222. When evaluating the accuracy, the sensor position accuracy evaluation unit 224 evaluates that the accuracy of the sensor position is low when the sensor position does not exist within the error range of the positioning result by the GPS receiving unit 170.

  In addition, the sensor position accuracy evaluation unit 224 is in a state where the GPS receiving unit 170 does not report a positioning result or the like, or a state where the accuracy of the positioning result or the like by the GPS receiving unit is low (hereinafter referred to as “GPS low accuracy state”) ) Continues for a predetermined time or more after the initialization of the sensor position, it is determined that the detection accuracy of various sensors in the travel sensor unit 160 is not guaranteed due to a change in sensor characteristics with time, and the accuracy of the sensor position is low. evaluate. Here, the “predetermined time” is determined in advance based on results of experiments, simulations, and the like.

  In addition, the sensor position accuracy evaluation unit 224 determines that if the GPS low accuracy state continues and the vehicle travels more than a predetermined movement distance based on the detection result by the speed sensor 161 or the acceleration sensor 163, the sensor position accuracy evaluation unit 224 Evaluate that position accuracy is low. Here, the “predetermined moving distance” is determined in advance by an experiment, an evaluation, or the like.

  The sensor position accuracy evaluation unit 224 is a sensor data processing unit when the driving direction changes by a predetermined amount or more based on the detection result by the angular velocity sensor 162 when the GPS low accuracy state continues. It is determined that the accuracy of the traveling direction calculated by 210 is low, and it is evaluated that the accuracy of the map matching position is low. Such a situation occurs, for example, when the vehicle travels over many floors in a high-rise parking lot as shown in FIG. Here, the “predetermined azimuth change amount” is determined in advance based on results of experiments and simulations.

  In addition, the sensor position accuracy evaluation unit 224 evaluates that the accuracy of the sensor position is low during a period in which the ambient temperature of the traveling sensor unit 160 is drastically changed, such as immediately after the navigation apparatus 100 is energized. In the present embodiment, the “period in which the ambient temperature of the traveling sensor unit 160 is drastically changed” is determined in advance based on the results of experiments and simulations. Of course, a period in which the ambient temperature of the traveling sensor unit 160 is drastically changed may be detected by measuring the temperature change with a thermometer.

  In addition, when the sensor position accuracy evaluation unit 224 determines that learning for processing of the detection result by the traveling sensor unit 160 is being performed based on information from the sensor data processing unit 210, the sensor position accuracy is low. And evaluate.

  The sensor position accuracy evaluation unit 224 evaluates that the sensor position accuracy is high except for the case where the sensor position accuracy is evaluated to be low as described above. In this way, when it is evaluated that the accuracy of the sensor position is high, that fact is reported to the map matching position correction unit 225.

  When the map matching position correcting unit 225 receives a report from the sensor position accuracy evaluating unit 224 that the sensor position accuracy is evaluated to be high, the map matching position correcting unit 225 includes the latest sensor position reported from the sensor position calculating unit 222, The distance from the map matching position reported most recently from the map matching position calculation unit 221 is calculated. If the calculated distance determines that the map matching position is far from the sensor position to the extent that correction is required, the map matching position correction unit 225 corrects the map matching position based on the sensor position. In this correction, for example, the map matching position correction unit 225 corrects the map matching position to the intersection position of the road and the line passing through the sensor position and orthogonal to the road where the map matching position exists as shown in FIG. .

[Operation]
Next, a description will be given mainly focusing on map matching position correction processing based on the sensor position executed in the navigation device 100 configured as described above.

<Initialization of sensor position>
First, sensor position initialization processing necessary for correcting the map matching position based on the sensor position will be described. This sensor position initialization process is performed when a new map matching position is calculated by the map matching position calculation unit 221 and when a new GPS positioning result is obtained by the GPS receiving unit 170. This is executed by the unit 223.

  In the sensor position initialization process, as shown in FIG. 7, first, in step S11, the sensor position initialization unit 223 determines whether or not the accuracy of the map matching position is high. In this determination, the sensor position initialization unit 223, as described above, (i) when the map matching position exists in the vicinity of the positioning result by the GPS receiving unit 170, or (ii) when the intersection is bent, etc. When the road direction changes at a predetermined angle or more in the map information 121, the distance error between the pre-matching position and the post-matching position (map matching position) obtained by matching on the map does not exceed the predetermined value In addition, it is determined that the accuracy of the map matching position is high.

  If the result of the determination in step S11 is affirmative (step S11: Y), the process proceeds to step S12. In step S12, the sensor position initialization unit 223 initializes the sensor position with reference to the map matching position. When initializing the sensor position, as described above, the sensor position initialization unit 223 initializes the sensor position to a position according to the attribute of the road on the road where the map matching position exists.

  If the result of the determination in step S11 is negative (step S11: N), the process proceeds to step S13. In step S13, the sensor position initialization unit 223 determines whether or not the accuracy of the positioning result by the GPS receiving unit 170 is high. In this determination, as described above, the sensor position initialization unit 223 performs GPS positioning in an environment without SA and without multipath, and when the PDOP is low, the accuracy of the positioning result is high. judge.

  If the result of determination in step S13 is negative (step S13: N), the sensor position initialization process ends without initializing the sensor position. On the other hand, when the result of the determination in step S13 is affirmative (step S13: Y), the process proceeds to step S14. In step S <b> 14, the sensor position initialization unit 223 initializes the sensor position to the position of the positioning result by the GPS receiving unit 170.

  Thus, when the sensor position is initialized, the initialization result is reported to the sensor position calculation unit 222, and the initial process of the sensor position is completed. Upon receiving this report, the sensor position calculation unit 222 replaces the sensor position so far with the reported sensor position, and then calculates the subsequent sensor position.

<Map matching position correction process based on sensor position>
Next, a map matching position correction process based on the sensor position will be described. In this correction process, as shown in FIG. 8, first, in step S21, the map matching position calculation unit 221 calculates the map matching position, and the sensor position calculation unit 222 calculates the sensor position.

  Next, in step S22, the sensor position accuracy evaluation unit 224 evaluates the accuracy of the sensor position. In this evaluation, the sensor position accuracy evaluation unit 224, as described above, (ii) when the sensor position does not exist within the error range of the positioning result by the GPS receiving unit 170, (ii) the GPS low accuracy state is the sensor. When the position continues for a predetermined time or more after initialization, (iii) When the GPS low-accuracy state continues, the traveling direction changes by a predetermined direction change amount or more based on the detection result by the angular velocity sensor 162 (Iv) When the GPS low-accuracy state continues and the vehicle travels more than a predetermined movement distance based on the detection result by the speed sensor 161 or the acceleration sensor 163, (v) the surroundings of the travel sensor unit 160 When it corresponds to a period when the temperature changes drastically, or (vi) learning for processing of the detection result by the traveling sensor unit 160 is in progress When determining the accuracy of the sensor position is evaluated as low. On the other hand, in cases other than the case where it is evaluated that the accuracy of the sensor position is low, the sensor position accuracy evaluation unit 224 evaluates that the accuracy of the sensor position is high.

  Subsequently, in step S23, the sensor position accuracy evaluation unit 224 determines whether or not the sensor position accuracy is high. If the result of this determination is negative (step S23: N), the process proceeds to step S21, and the above steps S21 to S23 are repeated until a positive determination result is obtained in step S23. It is.

  When the determination result in step S23 is affirmative (step S23: Y), the sensor position accuracy evaluation unit 224 reports to the map matching position correction unit 225 that the sensor position accuracy is high. Then, the process proceeds to step S24.

  In step S24, the map matching position correction unit 225 calculates a distance between the map matching position and the sensor position (hereinafter also simply referred to as “difference distance”). Subsequently, in step S25, the map matching position correction unit 225 determines whether or not the difference distance is equal to or greater than a predetermined distance. If the result of this determination is negative (step S25: N), it is determined that there is no need to correct the map matching position, and the process proceeds to step S21. Thereafter, the processes in steps S21 to S25 are repeated until a positive determination result is obtained in step S25.

  If the result of the determination in step S25 is affirmative (step S25: Y), the process proceeds to step S26. In step S26, the map matching position correction unit 225 corrects the map matching position with reference to the sensor position. In this correction, as described above, the map matching position correction unit 225 maps the intersection of the road and the line passing through the sensor position and orthogonal to the road where the map matching position exists, as shown in FIG. 6, for example. Correct the matching position.

  When the correction of the map matching position is thus completed, the process proceeds to step S21. Thereafter, the processes in steps S21 to S26 are repeated.

  As described above, in the present embodiment, the map matching position calculation unit 221 assumes that the vehicle travels on the road in the map information 121, and the positioning result by the GPS receiving unit 170 and the detection by the travel sensor unit 160. Based on the result, a map matching position is calculated. Further, the sensor position calculation unit 222 calculates the sensor position based on the detection result by the travel sensor unit 160. This sensor position is initialized by the sensor position initialization unit 223 when it is determined that the positioning result by the GPS receiving unit 170 or the accuracy of the map matching position is high.

  When the sensor position accuracy evaluation unit 224 evaluates that the accuracy of the sensor position to be appropriately initialized in this way is high, and the sensor position and the map matching position are separated from each other to some extent, the map matching position correction unit 225 However, the map matching position is corrected based on the sensor position. For this reason, when there is an error in road data, the map matching position can be corrected appropriately and accurately. Therefore, according to the present embodiment, the position of the vehicle can be obtained with high accuracy.

[Modification of Embodiment]
The present invention is not limited to the above-described embodiment, and various modifications are possible.

  For example, in the above embodiment, the map matching position is corrected based on the sensor position. The distance between the sensor position and the map matching position is a predetermined distance or more, and the sensor position and the map matching position are separated to a certain extent. To do in case. On the other hand, if the distance between the sensor position and the map matching position is greater than or equal to the second predetermined distance and is far away, it is determined that some inconvenience has occurred, and map matching is performed for failsafe. It is also possible not to perform position correction.

  In the above embodiment, the present invention is applied to a navigation device mounted on a vehicle. However, the present invention can also be applied to, for example, a navigation device mounted on an aircraft or a ship. Further, for example, the present invention can be applied to any device that performs route search such as a portable terminal device having a navigation function.

  In addition, the control unit 110 in the above-described embodiment is an arithmetic unit including a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), and the like. The computer may be configured to execute a process prepared in the above embodiment on a computer prepared in advance. These programs are recorded on a computer-readable recording medium such as a hard disk, CD-ROM, or DVD, and are read from the recording medium and executed by the computer. Further, these programs may be acquired in a form recorded on a portable recording medium such as a CD-ROM or DVD, or may be acquired in a form of delivery via a network such as the Internet. May be.

It is a block diagram which shows roughly the structure of the navigation apparatus which concerns on one Embodiment of this invention. It is a block diagram which shows roughly the structure of the map matching part of FIG. It is a figure for demonstrating the judgment processing example of the high or low precision of a map matching position. It is a figure which shows the example of initialization of a sensor position. It is a figure for demonstrating the example from which an azimuth | direction change amount becomes large. It is a figure which shows the example of correction | amendment of a map matching position. It is a flowchart for demonstrating the initialization process of the sensor position in the apparatus of FIG. It is a flowchart for demonstrating the correction process of the map matching position on the basis of the sensor position in the apparatus of FIG.

Explanation of symbols

100 ... Navigation device (position detection device)
160 ... Travel sensor unit (sensor means)
170 ... GPS receiving unit (positioning means)
221 ... Map matching position calculation unit (map matching position calculation means)
222 ... Sensor position calculation unit (sensor position calculation means)
223 ... Sensor position initialization unit (initialization means)
224 ... Sensor position accuracy evaluation unit (evaluation means)
225 ... Map matching position correction unit (correction means)

Claims (15)

Positioning means for positioning the position of the moving body based on information received from the outside of the moving body;
Sensor means mounted on the moving body for detecting a moving state of the moving body;
Sensor position calculating means for calculating a sensor position estimated as a current position of the moving body based on a detection result by the sensor means;
Map matching position calculating means for calculating a map matching position by performing matching on a map based on the positioning result by the positioning means and the detection result by the sensor means;
An evaluation means for evaluating the accuracy of the sensor position;
When the evaluation unit evaluates that the accuracy of the sensor position is high, and the map matching position and the sensor position are separated by a predetermined distance or more, the map matching position is corrected based on the sensor position. A position detecting device comprising: a correcting unit;   The position detection apparatus according to claim 1, further comprising an initialization unit configured to initialize the sensor position with reference to the map matching position when it is determined that the accuracy of the map matching position is high.   3. The position according to claim 2, wherein the initialization unit determines that the accuracy of the map matching position is high when the map matching position exists in the vicinity of a positioning result obtained by the positioning unit. Detection device.   The initialization means is obtained based on a positioning result by the positioning means, a detection result by the sensor means, and a previous map matching position in the movement of a moving path whose moving direction changes at a predetermined angle or more in the map information. 3. The accuracy of the map matching position is determined to be high when a distance error between the pre-matching position and the post-matching position obtained by the matching does not exceed a predetermined value. 4. The position detection device according to 3.   5. The position according to claim 2, wherein the initialization unit initializes the sensor position to a position determined according to an attribute of a moving path where the map matching position exists. Detection device.   The position detection apparatus according to claim 5, wherein the width of the moving path is included in the attribute of the moving path where the map matching position exists.   The position detection apparatus according to claim 1, further comprising an initialization unit that initializes the sensor position with reference to the positioning result when it is determined that the accuracy of the positioning result by the positioning unit is high. .   The said evaluation means evaluates that the precision of the said sensor position is low, when the said sensor position does not exist in the error range of the positioning result by the said positioning means. The position detection device according to one item.   The evaluation means evaluates that the accuracy of the sensor position is low when the positioning means is not performing positioning or when the positioning result accuracy by the positioning means is low for a predetermined time or longer. The position detection device according to any one of claims 1 to 8.   The evaluation means includes a movement over a predetermined distance and a direction over a predetermined amount of azimuth change during a period in which the positioning means is not performing positioning or a state where the positioning result accuracy by the positioning means is low. The position detection device according to claim 1, wherein when any of the changes occurs, it is evaluated that the accuracy of the sensor position is low.   The said evaluation means evaluates that the precision of the said sensor position is low, when it is judged that the temperature change of the circumference | surroundings of the said sensor means is intense, It is characterized by the above-mentioned. Position detection device.   The said evaluation means evaluates that the precision of the said sensor position is low, when it is judged that the learning for processing the detection result of the said sensor means is not progressing. The position detection device according to claim 1. A positioning step of positioning the position of the moving body based on information received from the outside of the moving body;
A movement state detection step of detecting a movement state of the moving body by means of sensor means mounted on the moving body;
A sensor position calculating step for calculating a sensor position based on a detection result in the movement state detecting step;
A map matching position calculating step of calculating a map matching position by performing matching on a map based on the positioning result in the positioning step and the detection result in the movement state detecting step;
An evaluation step for evaluating the accuracy of the sensor position;
A first determination step of determining whether or not the accuracy of the sensor position is evaluated in the evaluation step;
A second determination step of determining whether or not the map matching position and the sensor position are separated by a predetermined distance or more when the determination result in the first determination step is affirmative;
And a correction step of correcting the map matching position with reference to the sensor position when the determination result in the second determination step is affirmative.   A position detection program for causing a calculation means to execute the position detection method according to claim 13. 15. A recording medium in which the position detection program according to claim 14 is recorded so as to be readable by an arithmetic means.

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