JP4741291B2 - Navigation device - Google Patents

Description

  The present invention relates to a navigation device, and more particularly to a technique for calculating a vehicle orientation of an in-vehicle navigation device.

  Patent Document 1 describes an in-vehicle navigation device that detects a current vehicle orientation by detecting a displacement of a vehicle orientation by a gyro sensor and integrating the detected orientation displacements.

JP-A-7-92389

  However, when there are many turning operations of the vehicle such as in a parking lot, the accuracy of the vehicle direction may be reduced.

  The objective of this invention is providing the technique which calculates | requires a vehicle direction more accurately also in a parking lot.

  In order to solve the above problems, the navigation device of the present invention corrects the vehicle direction using the direction of the taxiway in the parking lot and the direction of the parking space.

  For example, the navigation device of the present invention calculates the road direction α before entering the parking lot and the vehicle direction in the parking lot using any one of α, α + 90 °, α + 180 °, and α + 270 °. Means.

More specifically, the navigation device of the present invention includes an azimuth displacement detection unit that detects a azimuth displacement, a vehicle azimuth calculation unit that integrates the azimuth displacement detected by the azimuth displacement detection unit to obtain a vehicle azimuth, A parking lot determination unit that determines whether or not the current position is in the parking lot, and when the parking lot determination unit determines that the current position is in the parking lot, the current position is determined before entering the parking lot. When the difference between the existing road direction α, α + 90 °, α + 180 ° and α + 270 ° and the vehicle direction X calculated by the vehicle direction calculation means is within a predetermined value, α, α + 90 °, α + 180 ° Or you may provide the vehicle direction correction means which corrects the said vehicle direction to the direction nearest to the said vehicle direction X among (alpha) +270 degrees .

  An embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of an in-vehicle navigation device 100 to which an embodiment of the present invention is applied. As shown in the figure, the in-vehicle navigation device 100 includes an arithmetic processing unit 1, a display 2, a storage device 3, a voice input / output device 4, an input device 5, a wheel speed sensor 6, a geomagnetic sensor 7, A gyro sensor 8, a GPS (Global Positioning System) receiver 9, an in-vehicle LAN device 11, an FM multiplex broadcast receiver 12, and a beacon receiver 13 are provided.

  The arithmetic processing unit 1 is a central unit that performs various processes. For example, the present location is detected based on information output from the various sensors 6 to 8 and the GPS receiver 9. Further, map data necessary for display is read out from the storage device 3 based on the obtained current location information. Further, the read map data is developed in graphics, and a mark indicating the current location is superimposed on the map data and displayed on the display 2. Also, an optimal route (recommended route) connecting the destination instructed by the user and the current location (departure location) using the map data stored in the storage device 3 and the traffic information received from the FM multiplex broadcasting station or beacon. ). Further, the user is guided using the voice input / output device 4 and the display 2.

  The display 2 is a unit that displays graphics information generated by the arithmetic processing unit 1. The display 2 is composed of a CRT, a liquid crystal display, or the like. The signal S1 between the arithmetic processing unit 1 and the display 2 is generally connected by an RGB signal or an NTSC (National Television System Committee) signal.

  The storage device 3 includes a storage medium such as a CD-ROM, DVD-ROM, HDD, or IC card. This storage medium stores map data.

  The map data includes, for each mesh identification code (mesh ID), which is a partitioned area on the map, link data of each link constituting a road included in the mesh area. The link data includes, for each link ID, coordinate information of two nodes (start node and end node) constituting the link, road type information including the link, link length information indicating the link length, link travel time, 2 The link ID (connection link ID) of the link connected to each node is included. Here, by distinguishing the start node and the end node for the two nodes constituting the link, the upward direction and the downward direction of the same road are managed as different links.

  The map data also includes information (position, size, etc.) of components such as parking lots other than roads included in the corresponding mesh area.

  The voice input / output device 4 converts the message to the user generated by the arithmetic processing unit 1 into a voice signal and outputs it. Also, a process of recognizing the voice uttered by the user and transferring the contents to the arithmetic processing unit 1 is performed.

  The input device 5 is a unit that receives instructions from the user. The input device 5 includes a hard switch such as a scroll key and a scale change key, a joystick, a touch panel pasted on a display, and the like.

  The sensors 6 to 8 and the GPS receiver 9 are used for detecting the current location (vehicle position) by the vehicle-mounted navigation device 100. The wheel speed sensor 6 measures the distance from the product of the wheel circumference and the measured number of rotations of the wheel, and further measures the angle at which the moving body is bent from the difference in the number of rotations of the paired wheels. The geomagnetic sensor 7 detects the magnetic field held by the earth and detects the direction in which the moving body is facing. The gyro 8 is configured by an optical fiber gyro, a vibration gyro, or the like, and detects an angle at which the moving body rotates. The GPS receiver 9 receives a signal from a GPS satellite and measures the distance between the mobile body and the GPS satellite and the rate of change of the distance with respect to three or more satellites to thereby determine the current position, travel speed, and travel of the mobile body Measure orientation.

  The in-vehicle LAN device 11 receives various information of the vehicle on which the in-vehicle navigation device 100 is mounted, such as door opening / closing information, light lighting state information, engine status, failure diagnosis result, and the like.

  The FM multiplex broadcast receiving device 12 receives rough current traffic information, regulation information, SA / PA (service station / parking) information, parking lot information, weather information, etc. sent from the FM multiplex broadcast station as FM multiplex broadcast signals. To do.

  The beacon receiving device 13 receives current traffic information, regulation information, SA / PA information, parking lot information, and the like sent from the beacon.

  FIG. 2 is a functional block diagram of the arithmetic processing unit 1.

  As illustrated, the arithmetic processing unit 1 includes a user operation analysis unit 41, a route search unit 42, a route guidance unit 43, a vehicle orientation calculation unit 44, a current position calculation unit 45, an information storage unit 46, A display processing unit 47.

  The user operation analysis unit 41 receives a request from the user input to the input device 5, analyzes the request content, and controls each unit of the arithmetic processing unit 1 so that processing corresponding to the request content is executed. To do. For example, when a user requests a search for a recommended route, the display processing unit 47 is requested to display a map on the display 2 in order to set a destination. Further, it requests the route search unit 42 to calculate a route from the current location (departure location) to the destination.

  The vehicle azimuth calculation unit 44 obtains the displacement of the vehicle azimuth by integrating the angular data obtained as a result of integrating the angular acceleration data S7 measured by the gyro 8 with the time axis, and provides an initial vehicle azimuth as a reference. To get the current vehicle direction. Further, the vehicle orientation is periodically corrected by the orientation obtained from the geomagnetic sensor 7 and the GPS receiver 9. Further, in the parking lot, processing for correcting the vehicle direction is performed as will be described later.

  The current position calculation unit 45 integrates distance data obtained as a result of integrating the distance pulse data S5 measured by the wheel speed sensor 6 on the time axis to obtain a movement distance, and calculates the movement distance and the vehicle direction calculation unit 44. The virtual current position (X ′, Y ′) that is the position after traveling from the initial position (X, Y) is periodically calculated using the vehicle azimuth obtained by the above. Further, the virtual current position is matched with the road (link) having the highest shape correlation by map matching processing to obtain the current position (display position).

  The route search unit 42 uses a Dijkstra method or the like to search for a route that minimizes the cost (for example, travel time) of a route connecting two designated points (current location, destination).

  The route guidance unit 43 performs route guidance using the route searched by the route search unit 42. For example, the information on the route is compared with the information on the current location, and the voice input / output device 4 is used to inform the user by voice whether the vehicle should go straight before passing an intersection or the like. Further, the route guiding unit 43 displays the direction to travel on the map displayed on the display 2 and notifies the user of the recommended route.

  The information storage unit 46 stores the guidance route searched by the route search unit 42 and the traveling locus of the vehicle.

  The display processing unit 47 receives map data in an area required to be displayed on the display 2 from the storage device 3, and at a specified scale and drawing method, roads, other map components, current location, destination, A map drawing command is generated so as to draw a mark such as an arrow for the recommended route. Then, the generated command is transmitted to the display 2.

  FIG. 3 is a diagram illustrating a hardware configuration example of the arithmetic processing unit 1.

  As illustrated, the arithmetic processing unit 1 has a configuration in which devices are connected by a bus 32. The arithmetic processing unit 1 includes a CPU (Central Processing Unit) 21 that executes various processes such as numerical calculation and control of each device, and a RAM (Random Access Memory) that stores map data, arithmetic data, and the like read from the storage device 3. ) 22, a ROM (Read Only Memory) 23 for storing programs and data, a DMA (Direct Memory Access) 24 for transferring data between the memories and between the memory and each device, and graphics drawing. In addition, a drawing controller 25 that controls display, a video random access memory (VRAM) 26 that stores graphics image data, a color palette 27 that converts image data into RGB signals, and an A / D that converts analog signals into digital signals. Converter 28 and an SCI (Serial Communication Interface) that converts the serial signal into a parallel signal synchronized with the bus. ace) 29, a PIO (Parallel Input / Output) 30 that puts a parallel signal on the bus in synchronization with the bus, and a counter 31 that integrates the pulse signal.

  [Description of Operation] Next, the operation of the in-vehicle navigation device 100 having the above-described configuration will be described.

  As described above, the current position calculation unit 45 of the in-vehicle navigation device 100 calculates the virtual current position based on the relative displacement including the moving distance and the azimuth displacement of the vehicle with reference to the initial position (current position obtained last time). Ask. Then, the virtual current position is matched with the road (link) having the highest shape correlation (map matching process), and the current position is calculated. At this time, the current position calculation unit 45 assumes that there is a correlation when the difference between the vehicle direction and the road direction is within a predetermined value. If there is no road within the predetermined range where the difference between the vehicle direction and the road direction is within the predetermined value, the current position calculation unit 45 cannot obtain the current position on the road, so the virtual current position is left as it is. The current position.

  Thus, the vehicle orientation plays an important role in obtaining the current position. Therefore, the vehicle-mounted navigation device 100 needs to obtain the vehicle direction more accurately. However, in the parking lot, the vehicle often turns and the accuracy of the vehicle direction tends to decrease. In a parking lot, GPS signals may not be received, and vehicle orientation may not be corrected.

  In the present embodiment, in consideration of the problem in the parking lot, the vehicle orientation is corrected by the process shown in FIG. 4 in the parking lot.

  Here, the reason why the vehicle direction is accurately obtained in advance by the processing of FIG. 4 will be described.

  FIG. 5 shows the shape of a general parking lot 500. The general parking lot 500 is often rectangular in plan view. And the guideway 501 to the parking space in a parking lot is provided along one of the directions of four sides of a parking lot. Since the parking lot 500 is normally constructed along the adjacent road R, the taxiway 501 is arranged parallel or perpendicular to the direction α of the adjacent road R. Then, the vehicle A travels in the parking lot 500 as the locus Q and parks in the parking space 502.

  In the parking lot 500, the vehicle A frequently turns, so that the accuracy of the vehicle direction is likely to be lowered. On the other hand, the vehicle direction β is considered to be the same as the direction α of the adjacent road, or approximate to α + 90 °, α + 180 °, or α + 270 ° from the relationship of the arrangement of the taxiway 501.

  Therefore, in the present embodiment, only when the conditions shown in the processing flow of FIG. 4 are satisfied, the vehicle direction β is adjusted to these directions (directions determined according to the shape of the parking lot) to prevent the deviation due to the turning operation. Therefore, the vehicle direction was determined with high accuracy.

  Hereinafter, the processing flow of FIG. 4 will be described.

  First, the vehicle orientation calculation unit 44 determines whether or not the vehicle has entered the parking lot. In the present embodiment, the vehicle orientation calculation unit 44 determines that the vehicle has entered the parking lot when the current position is located at the parking lot position included in the map data. However, there is no particular limitation on the method for determining whether or not the vehicle has entered the parking lot. A specific turning operation when entering the parking lot may be registered, and it may be determined that the vehicle has entered the parking lot when the vehicle performs this specific turning operation.

  When it is not determined that the vehicle has entered the parking lot (No in S102), the vehicle orientation calculation unit 44 ends the vehicle orientation correction processing.

  On the other hand, when it is determined that the vehicle has entered the parking lot (Yes in S102), the vehicle direction calculation unit 44 stores the road direction α of the link where the current position exists until immediately before in the information storage unit 46. (S104).

  This will be described with reference to FIG. In FIG. 5, it is assumed that the vehicle A travels along the adjacent road R and enters the parking lot 500 as indicated by the trajectory Q. When the vehicle A leaves the road R and enters the parking lot 500, the current position calculation unit 45 obtains a current position that is not on the road (not matched with the road). At this time, the vehicle orientation calculation unit 44 refers to the position of the parking lot 500 in the map data, confirms that the current position exists at the position of the parking lot 500, and determines that the vehicle has entered the parking lot 500 (S102). Yes). Furthermore, the road direction α of the road R that has been matched last is acquired from the map data and stored in the information storage unit 46. Since the map data includes the coordinates of the start node and end node of the link that constitutes the road, the road direction can be obtained from the direction of the link.

  Next, the vehicle direction calculation unit 44 determines whether or not the straight traveling state has continued for a predetermined distance (for example, 10 m) (S106). Whether the vehicle is traveling straight can be determined by whether the gyro sensor 8 detects turning of the vehicle. Note that this determination is made because it can be assumed that the vehicle is a general rectangular parking lot as shown in FIG.

  When the straight traveling state does not continue for a predetermined distance (No in S106), the vehicle orientation calculation unit 44 proceeds to S122. In this way, when the straight traveling state does not continue, the vehicle heading is not corrected because the guideway 511 in the parking lot 510 is a curve or the guideway is determined as shown in FIG. This is because it may be a small parking lot that is not used. In such a case, it is better not to perform the process of aligning the vehicle direction with any of the four sides of the parking lot.

  Returning to FIG.

When the straight line state continues for a predetermined distance ( Yes in S106), the vehicle orientation calculation unit 44 calculates the vehicle orientation β by the above method (S108). That is, the current vehicle orientation β is obtained by adding the displacement of the orientation obtained from the gyro sensor 8 to the reference orientation (vehicle orientation obtained last time).

  Next, the vehicle bearing calculation unit 44 sets i = 0 (S110). Furthermore, the vehicle orientation calculation unit 44 obtains an orientation difference θ between the vehicle orientation β and the four-side direction of the parking lot by the formula: θ = {α + 90 × i} −β.

  Next, the vehicle orientation calculation unit 44 determines whether or not θ <−30 ° or θ> 30 ° (S114). Note that this determination is made because there is a non-square parking lot 520 as shown in FIG. In the case of a parking lot 520 that is not square, the direction of the taxiway 521 may not be any of the road directions α, α + 90 °, α + 180 °, and α + 270 °, and it is not appropriate to adjust the vehicle direction β to these directions. It is.

  When θ <−30 ° or θ> 30 ° is not satisfied, that is, when −30 ≦ θ ≦ 30 ° (No in S114), the vehicle orientation calculation unit 44 sets the vehicle orientation β to any of the four side orientations of the parking lot. Fit in. Specifically, the vehicle orientation β = (α + 90 × i) is set (S120). Thereafter, the process proceeds to S122.

  On the other hand, if θ <−30 ° or θ> 30 (Yes in S114), the vehicle bearing calculation unit 44 determines whether i <3 (S110). If i <3, i is incremented ( S118), the process returns to S112 and continues. If i <3 is not satisfied (No in S116), the vehicle orientation calculation unit 44 proceeds to the process of S122 described later.

  Thus, the vehicle direction is adjusted to a value closer to any one of the road direction α, α + 90 °, α + 180 °, and α + 270 °.

  Next (after S122 or No in S106), the vehicle bearing calculation unit 44 determines whether or not the vehicle has escaped parking based on the latest current position calculated by the current position calculation unit 45 ( S122). Specifically, the determination is made based on whether or not the current position deviates from the parking lot position of the map data, as in the case where the entry to the parking lot is determined in S102.

  When it is determined that the vehicle has not escaped from the parking lot (No in S122), the vehicle orientation calculation unit 44 returns to S106 and continues the process.

  On the other hand, when it determines with the vehicle having escaped the parking lot (it is Yes at S122), the vehicle direction calculation part 44 complete | finishes a direction correction process.

  The vehicle orientation correction processing has been described above. After exiting the parking lot, the current position calculation unit 44 obtains a new current position using the vehicle direction corrected in this way.

  The embodiment of the present invention has been described above.

  According to this embodiment, a vehicle direction can be calculated | required more accurately within a parking lot. Even when the vehicle exits the parking lot, the current position can be calculated using the vehicle orientation that is accurately obtained.

  The present invention is not limited to the above embodiment. The above-described embodiment can be variously modified within the scope of the invention.

  For example, using the fact that the direction of the parking space 502 in the parking lot is usually one of the four sides of the parking lot as shown in FIG. May be performed. Specifically, when the vehicle stops back and the engine stop is detected, the vehicle direction is set to the road direction α, α + 90 °, α + 180 °, which has been matched immediately before, as in S108 to S120 in FIG. The angle is adjusted to either α + 270 °. The vehicle direction may be corrected when the engine is started.

  In the above embodiment, an example in which the present invention is applied to a vehicle-mounted navigation device has been described. However, the present invention can also be applied to a navigation device other than a vehicle-mounted navigation device.

FIG. 1 is a schematic configuration diagram of an in-vehicle navigation device to which an embodiment of the present invention is applied. FIG. 2 is a diagram illustrating a functional configuration of the arithmetic processing unit 1. FIG. 3 is a diagram illustrating a hardware configuration of the arithmetic processing unit 1. FIG. 4 is a flowchart of the vehicle orientation correction process in the parking lot. FIG. 5 is a plan view of the parking lot. FIG. 6 is a plan view of the parking lot. FIG. 7 is a plan view of the parking lot.

Explanation of symbols

100: In-vehicle navigation device,
DESCRIPTION OF SYMBOLS 1 ... Arithmetic processing part, 2 ... Display, 3 ... Memory | storage device, 4 ... Audio | voice input / output device, 5 ... Input device, 6 ... Wheel speed sensor, 7 ... Geomagnetic sensor, 8 ... Gyro, 9 ... GPS receiver, 11 ... In-car LAN device, 12 ... FM multiplex broadcast receiving device, 13 ... Beacon receiving device,
21 ... CPU, 22 ... RAM, 23 ... ROM, 24 ... DMA, 25 ... Drawing controller, 26 ... VRAM, 27 ... Color palette, 28 ... A / D converter, 29 ... SCI, 30 ... PIO, 31 ... Counter,
DESCRIPTION OF SYMBOLS 41 ... User operation analysis part, 42 ... Route search part, 43 ... Route guidance part, 44 ... Vehicle direction calculation part, 45 ... Current position calculation part, 46 ... Information storage part, 47 ... Display processing part

Claims (4)

A navigation device,
Azimuth displacement detection means for detecting azimuth displacement;
Vehicle azimuth calculation means for integrating the displacement of the azimuth detected by the azimuth displacement detection means to obtain the vehicle azimuth;
A parking lot judging means for judging whether or not the current position is in the parking lot;
When it is determined by the parking lot determination means that the current position is in the parking lot, the road direction α, the α + 90 °, the α + 180 °, the α + 270 °, and the α + 270 ° where the current position exists before entering the parking lot When the difference from the vehicle direction X calculated by the vehicle direction calculation means is within a predetermined value, the vehicle direction is corrected to the direction closest to the vehicle direction X among the α, α + 90 °, α + 180 ° or α + 270 °. And a vehicle orientation correcting means. In claim 1,
A straight traveling determination means for determining whether or not the vehicle has traveled a predetermined distance in a straight traveling state in a parking lot;
The vehicle azimuth correcting means is
A navigation device, wherein the vehicle direction is corrected when it is determined by the straight traveling determination means that the vehicle has traveled a predetermined distance in a straight line in a parking lot. A navigation device,
Azimuth displacement detection means for detecting azimuth displacement;
Vehicle azimuth calculation means for integrating the displacement of the azimuth detected by the azimuth displacement detection means to obtain the vehicle azimuth;
Parking determination means for determining whether or not the current position is parked in the parking lot;
When it is determined by the parking determination means that the current position is parked in the parking lot, the vehicle direction calculation means calculates the road directions α, α + 90 °, α + 180 ° and α + 270 ° where the current position existed before entering the parking lot. Vehicle orientation correcting means for correcting the vehicle orientation to an orientation closest to the vehicle orientation X among the α, α + 90 °, α + 180 °, or α + 270 ° when the difference from the calculated vehicle orientation X is within a predetermined value. A navigation device comprising: In claim 1 or 3,
A navigation apparatus comprising means for calculating a current position using the vehicle direction corrected by the vehicle direction correction means.

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