JP2006343194A - Car navigation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a car navigation system capable of showing a route intelligibly. <P>SOLUTION: In this car navigation system, guide route is performed by using a head-up display. When searching for a route, the car navigation system projects it on a front glass so that an arrow showing the route is overlapped on an actual road in the front visual field. In this case, the arrow is a continuous line wherein a position in contact with own car is used as a start point and a target spot in front as much as a prescribed distance (for example, 100m ahead) is used as an end point. Since the vehicle is connected to the target spot by the continuous line in this way, the way of traveling can be acquired intuitively, even if, for example, the front visual field is blocked by a car running just before own car. A transmission type display mounted on the front glass is formed by sticking many small polarizing plates dispersed onto a transparent film. Since the display has high transparency of a gap between each polarizing plate, the front visual field can be viewed clearly even in the nighttime or in a tunnel. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a car navigation system.

  2. Description of the Related Art A car navigation device that searches for a route to a destination using vehicle position information obtained using GPS and an electronic map and displays the route on a small display installed in front of a driver's seat is used. . A more convenient car navigation device is desired.

Patent Document 1 discloses an in-vehicle navigation device. This in-vehicle navigation device includes display means for reflecting light on the windshield so that the driver can see the route guidance image superimposed on the front scenery.
JP-A-7-262492

An object of the present invention is to provide a car navigation system whose route is easy to understand.
Another object of the present invention is to provide a car navigation system that displays a route superimposed on an actual field of view.
It is still another object of the present invention to provide a car navigation system that displays a route by accurately overlaying an actual field of view without depending on characteristics of a driver and a vehicle.
Still another object of the present invention is to provide a car navigation system that displays a route by accurately superimposing it on an actual field of view without depending on the inclination angle of the vehicle.
Still another object of the present invention is to provide a car navigation system using a head-up display that has a good field of view and can clearly recognize a projected image.

  In the following, means for solving the problem will be described using the numbers used in [Best Mode for Carrying Out the Invention] in parentheses. These numbers are added to clarify the correspondence between the description of [Claims] and [Best Mode for Carrying Out the Invention]. However, these numbers should not be used to interpret the technical scope of the invention described in [Claims].

  The car navigation system according to the present invention includes a position information generation unit (1) that generates position information indicating the current position of the vehicle (22), and a route calculation unit that generates path information indicating a route to the input destination ( 16) and a target position calculation unit (52) that calculates a target position that is a predetermined distance forward from the current position along the route using the current position as a starting point, and a driver of the vehicle (22). On the other hand, a screen (15) for overlaying an image on the front field of view of the vehicle (22), and a position (34) that overlaps the current position on the ground (20) in the front field when viewed from the position of the eyes (28). The guide line drawing unit (54) for drawing the guide line image (32) having the position (36) overlapping the target position as the other end and the guide line image (32) projected on the screen (15). And a shadow portion (14).

  The car navigation system according to the present invention includes a vehicle speed sensor (9) that detects the speed of the vehicle (22), and a guide line length setting unit (56) that sets a predetermined distance longer as the speed increases.

  The car navigation system according to the present invention includes a display screen (12) for displaying a map, a first input device (7-1) for designating a calibration point which is a position on the map, and a calibration position on the screen (15). And a calibration image drawing unit (58) for creating a calibration image for designating. The projection unit (14) projects a calibration image on the screen (15). The car navigation system further includes a second input device (7-2) for setting a setting position of the calibration image projected on the screen (15). The guide line drawing unit (13) adjusts the position of the guide line image (32) using the set position.

  In the car navigation system according to the present invention, when viewed from the position of the eye at a preset reference position, the calibration video image has a position (34) that overlaps the current position on the ground in the forward field of view as a calibration position. It includes a line with the overlapping position (36) as the other end.

  The car navigation system according to the present invention includes a gyro sensor unit (10) that detects an inclination angle of the vehicle (22) with respect to a horizontal plane. The guide line drawing unit (13) adjusts the position of the guide line image (32) using the set position.

  In the car navigation system according to the present invention, when the target position is located farther than the corner in the route, the distance from the current position to the target position is temporarily shorter than the predetermined position until the current position approaches the corner. A bend corner processing unit (60) for resetting the target position is provided.

  In the car navigation system according to the present invention, the screen (15) is provided on the transparent film (38) and the plurality of polarizing plates (40) which are installed on the film (38), have a gap between them and have the same polarization direction. ). The projection unit (14) projects the guide line image (32) onto the screen (15) with light having a polarization direction different from that of the polarizing plate (40).

  The screen for head-up display (15) according to the present invention includes a film disposed on a windshield and a plurality of polarizing plates disposed uniformly and in a predetermined area on the film. The average visible light transmittance in the predetermined region is 70% or more.

  The car navigation system according to the present invention is installed on the film (38), a transparent film (38) installed between the driver's eyes (28) of the vehicle (22) and the front view of the vehicle (22), A plurality of polarizing plates (40) having a gap between them and the same polarization direction, and an image for guiding the traveling direction of the vehicle (22) with light having a polarization direction different from that of the polarizing plate (40). A projection unit (14) for projecting onto the film (38).

According to the present invention, a car navigation system in which a route is easy to understand is provided.
Furthermore, according to the present invention, there is provided a car navigation system that displays a route superimposed on an actual field of view.
Furthermore, according to the present invention, there is provided a car navigation system that displays a route by accurately overlaying an actual field of view without depending on characteristics of a driver and a vehicle.
Furthermore, according to the present invention, there is provided a car navigation system that displays a route by accurately overlaying an actual field of view without depending on the inclination angle of the vehicle.
Furthermore, according to the present invention, there is provided a car navigation system using a head-up display that has a good field of view and can clearly recognize a projected image.

  The best mode for carrying out a car navigation system according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of a car navigation system according to the present embodiment. The car navigation system is installed in the vehicle. The car navigation system includes a GPS receiver 1 that receives radio waves from a GPS (Global Positioning System) satellite and generates information on the position and direction of the vehicle. The GPS receiver 1 detects the position of the vehicle by a single positioning method that detects the position with an accuracy of about 10 m to 100 m. More preferably, the GPS receiver 1 detects the position of the vehicle by an RTKGPS (Real Time Kinematic GPS) system that detects the position with an accuracy of a centimeter order. By using the RTKGPS method, the position information is updated at a cycle of about 0.1 seconds, and the position information of the vehicle can be obtained substantially in real time.

  The car navigation system further includes a VICS beacon receiver 2. The VICS beacon receiver 2 receives beacon information transmitted from a radio wave beacon or an optical beacon installed on the roadside. The beacon information includes traffic jam information, regulation information, current position information, destination guidance, branch information, accident information, parking lot information, character information, and simple graphic information.

The car navigation system further includes an FM receiver 3 that receives and processes FM broadcast radio waves.
The car navigation system further includes a CD / DVD driver 5. The CD / DVD driver 5 reads information from a recording medium (CD or DVD) 4 on which map data is recorded.

The car navigation system further includes an operation unit 7. The operation unit 7 includes an operation panel, a touch screen, and / or a keyboard having cursor keys. The operation unit 7 includes a first input device 7-1 and a second input device 7-2.
The car navigation system further includes a speed sensor 9. The speed sensor 9 detects the speed by processing a pulse signal obtained from a rotation signal generator attached to the axle of the vehicle.

  The car navigation system further includes a gyro sensor 10 that detects a relative direction. The gyro sensor 10 detects the angular momentum, and detects the rotational motion with respect to the inertial space of the case provided in the gyro sensor 10. The gyro sensor 10 detects a movement around one axis or two axes orthogonal to the axis of angular momentum. By matching the signal generated by the gyro sensor 10 with the map data read by the CD / DVD driver 5, a signal for outputting the current position of the vehicle and the travel route is extracted.

  The car navigation system further includes a storage processing device 11. The storage processing device 11 includes ROM, DRAM, SRAM, and VRAM.

  The car navigation system further includes a drawing processing device 8. The drawing processing device 8 generates an image signal including map data and video information processed by a main CPU 6 described later. When the map data recorded on the recording medium 4 is read by the CD / DVD driver 5, the drawing processing device 8 records the latest display data of the map data including route information in the storage processing device 11 in advance.

  The drawing processing device 8 reads map data and guidance information of an area including the current position of the vehicle from the map data recorded on the recording medium 4 via the CD / DVD driver 5. The drawing processing device 8 generates an image signal for displaying a video including the read information. The drawing processing device 8 includes control means for performing control for displaying a map, the current position of the vehicle, intersection information, and guidance route information. The drawing processing device 8 generates an image signal for displaying a mark indicating the current position of the vehicle on the read map.

The display unit 12 includes a liquid crystal display having a touch panel function. The display unit 12 displays a video based on the image signal received from the drawing processing device 8 on the display. The map displayed on the display unit 12 is automatically scrolled as the current position of the vehicle moves. The display screen is updated so that the current location is always displayed.
The car navigation system further includes a route search unit 16.

  The map data used by the car navigation system is characterized as follows. The car navigation system uses a geographic information system. Geographic information systems are essential for the management and analysis of information used by car navigation systems. The map data includes geographic information exemplified by roads, buildings, and rivers in the form of vector data. This vector data includes space information as point, line, and surface information defined by position coordinates and attribute values.

  The car navigation system includes a main CPU 6. The main CPU 6 includes a GPS receiver 1, a VICS information receiver 2, an FM receiver 3, a CD / DVD driver 5, an operation unit 7, a drawing processing device 8, a speed sensor 9, a gyro sensor 10, a storage processing device 11, and a route search unit. 16 to communicate.

  The car navigation system further includes an arrow drawing device 13 connected to the main CPU 6. The arrow drawing device 13 is connected to an arrow projection device 14 including a projector. The arrow projection device 14 projects an image on a predetermined position of the windshield 24. A windshield display unit 15 is provided on the windshield 24.

  FIG. 2 shows the configuration of the arrow drawing device 13. The arrow drawing device 13 includes a target position calculation unit 52, an arrow drawing unit 54, an arrow length setting unit 56, a calibration unit 58, a corner processing unit 60, and a slope processing unit 61.

  FIG. 3 shows a vehicle including the car navigation system according to the present embodiment. A driver boardes the vehicle 22. The GPS receiver 1 is installed at a GPS receiver installation position 30. The arrow projection device 14 is installed on a dashboard or a ceiling, and projects an arrow 32 onto the windshield display unit 15 of the windshield 24. When viewed from the eyes 28 of the driver, the starting point and the ending point of the arrow 32 overlap with the arrow starting point 34 and the arrow ending point 36 that are the positions of the ground 20 that can be seen in the driver's front view.

  FIG. 4 shows the configuration of the windshield display unit 15. The windshield display unit 15 includes a transparent film 38 with high transparency. An adhesive layer is provided on the surface of the transparent film 38. A large number of small polarizing plates 40 are adhered to the adhesive layer in a dispersed manner with the same polarization direction. The polarizing plates 40 have a gap between each other. In the region where the polarizing plate 40 is substantially uniformly distributed, the area occupied by the polarizing plate 40 in the windshield display unit 15 is preferably 50% or less. The average visible light transmittance in a region including a considerable number of polarizing plates 40 in the windshield display unit 15 is preferably 70% or more.

  The polarizing plate 40 is further covered with another transparent film (not shown). That is, the polarizing plate 40 is sandwiched between two transparent films. Such a polarizing plate 40 is easy to manufacture and is suitable for retrofitting the windshield 24. The arrow projection device 14 provides the driver with an image projected on the polarizing plate 40 by projecting light polarized perpendicular to the polarization direction of the polarizing plate 40.

  In such a windshield display unit 15, the gap between the polarizing plate 40 and the polarizing plate 40 is very high in transparency, so that the visibility is rarely hindered. Even if the transparency of the polarizing plate 40 is relatively low, it is possible to obtain the windshield display unit 15 having high transparency. When the area of the polarizing plate 40 is 50 percent or less, for example, even when the transmittance of the polarizing plate 40 is about 40 percent with respect to visible light, the windshield display portion having a transmittance of substantially 70 percent or more. 15 can be obtained. Such a windshield display unit 15 has high visibility of the front view especially in a tunnel or at night. Since the polarizing plate 40 having a high reflectance can be employed while maintaining the transparency of the windshield display unit 15 high, the luminance required for the arrow projection device 14 can be reduced, and the cost can be reduced.

  It is also possible to project an image using the windshield display unit 15 in which reflective members that do not transmit light are dispersedly arranged instead of the polarizing plate 40. In order to obtain the same average transmittance, the area of the polarizing plate 40 can be set larger than the area of the reflecting member, which is preferable.

  The operation of the car navigation system having the above configuration will be described as follows. FIG. 5 is a flowchart showing the initial adjustment operation of the car navigation system.

  The driver turns on a main switch provided in the operation unit 7 of the car navigation system (step S2). The driver turns on the power switch of the display provided in the display unit 12 (step S4).

  The main CPU 6 reads data such as map data from the recording medium 4 using the CD / DVD driver 5 (step S6).

  The GPS receiver 1 generates current position information indicating the GPS receiver installation position 30 based on the received GPS signal. The main CPU 6 acquires the current position information (step S8). Up to this point, the main CPU 6 has read the map data including the current position from the CD / DVD drive.

  The display unit 12 displays a map including the current position read in step S8. A mark indicating the current position of the vehicle is displayed on this map. The driver refers to the display unit 12 and inputs the direction in which the vehicle travels from the operation unit 7 (step S10).

  It is determined whether or not the actual size adjustment of the arrow has been completed. When the driver performs a predetermined operation on the operation unit 7, it is determined that the actual size adjustment of the arrow has not been completed, and the main CPU 6 performs the processing from step S14. When the driver performs another operation, it is determined that the actual size adjustment of the arrow has been completed, and the main CPU 6 performs the processing from step S24.

  The driver refers to the display unit 12, selects an appropriate target located in the traveling direction of the vehicle from the map on the display screen, and designates the position as a calibration position by the first input device 7-1. The calibration unit 58 draws an arrow using the calibration position. The arrow to be drawn is preferably set as follows. That is, when a standard driver and a vehicle are set in advance and viewed from the eyes 28 of the driver, the arrow end point 36 of the projected arrow is the position of the designated target. Furthermore, the arrow starting point 34 of the projected arrow is located at the front end of the vehicle 22 or slightly ahead of the front end as viewed from the driver's eyes 28 (step S16).

  The arrow projection device 14 projects the arrow drawn by the arrow drawing device 13 onto the windshield display unit 15. The arrow start point 34 of the projected arrow may deviate from the tip of the vehicle 22 depending on the driver and the personality of the vehicle 22. Depending on the individuality of the driver and the vehicle 22, the arrow end point 36 of the projected arrow may deviate from the target specified in step S14 (step S18).

  The driver sets the arrow start point 34 and the arrow end point 36 using the second input device 7-2. That is, the driver looks at the arrow 32 and inputs from the operation unit 7 so that the arrow starting point 34 is positioned at the tip of the vehicle 22 or slightly forward. The driver further inputs from the operation unit 7 so that the arrow end point 36 coincides with the position of the target designated in step S14.

  The calibration unit 58 stores the length of the arrow set in step S20 in the windshield display unit 15 and the distance between the front end of the vehicle and the target designated in step S14 in association with each other. Further, a correspondence between the length of the arrow on the windshield display unit 15 and the distance on the ground 20 is created from them (step S22).

  The driver sets the length when the arrow is projected onto the ground via the operation unit 7, that is, the length L between the arrow starting point 36 and the arrow ending point 38. The driver selects an appropriate length from among candidates such as 300 m, 180 m, 120 m, and 30 m as L. This length is preferably set long in a place with a good view and short in a place with a bad view. Alternatively, the driver selects to automatically set the length when the arrow is projected onto the ground (step S24).

The driver inputs an arrow display color from the operation unit 7 (step S26).
Arrow projection guidance is started, and the initial adjustment operation ends (step S28).

  Such initial adjustment is effective in solving the following problems. The correspondence between the arrow displayed on the windshield and the arrow starting point 34 and arrow ending point 36 displayed on the ground 20 is the height of the eye 28, the relative position of the eye 28 and the windshield 24, and the inclination of the windshield 24. It depends on the conditions. By the above initial adjustment, an arrow is displayed in conformity with the height and posture of the driver and the vehicle type.

  Next, the operation of driving using the car navigation system will be described as follows.

  The driver turns on the car navigation system. The GPS receiver 1 detects the current position of the vehicle 22 (GPS receiver installation position 30) and transmits it to the main CPU 6. The display unit 12 displays an electronic map and the current position of the vehicle in the electronic map. The driver sets the destination using the operation unit 7 while referring to the display unit 12. The route search unit 16 searches for an appropriate route from the current position to the destination and displays it on the display unit 12.

  The driver starts running. The GPS receiver 1 detects the current position of the vehicle substantially in real time and transmits it to the main CPU 6. The display unit 12 displays a mark indicating the current position of the vehicle 22 and a map around the current position.

  The arrow drawing unit 54 reads L set in step S24. The target position calculation unit 52 uses the current position detected by the GPS receiver 1 to calculate a point that is a distance L away from the current position along the searched route as the target position. The arrow drawing unit 54 draws an arrow 32 for connecting an arrow start point 34 that is a predetermined distance away from the current position and an arrow end point 36 that is a distance L ahead from the arrow start point 34 along the searched route. Instead of the arrow 32, a line without an arrow having an arrow start point 34 and an arrow end point 36 at both ends may be used.

  The arrow projection device 14 projects the drawn arrow onto the windshield display unit 15. An arrow 32 is displayed on the windshield display unit 15 so as to overlap the road in the forward field of view. For example, when the angle to be turned to the right is visible 100m ahead in the front view, the driver's eyes 28 extend from the front end of the vehicle to 100m ahead, and the arrow turning to the right after 100m is as if it is an actual road It looks as if it is displayed above. The driver will drive with reference to the arrow. The driver does not have to shift his gaze from the actual front view. Therefore, the burden on the driver is small and driving is performed safely.

  Since a continuous arrow from the front end of the vehicle to the target position is displayed, the road to be traveled is easy to understand. In particular, when there is something that obstructs the field of view, such as when another vehicle is traveling in front of the vehicle 22, compared to the arrow displayed near the place where the vehicle 22 turns away from the tip of the vehicle 22, Intuitively understand the positional relationship with the place to change direction.

  When the setting of the length of the arrow 32 is set to automatic, the length of the arrow is set as follows. The speed sensor 9 detects the speed of the vehicle 22 in real time. The arrow length setting unit 56 stores one or more reference speeds. The arrow length setting unit 56 sets the length L of the arrow to a longer length when the speed detected by the speed sensor 9 becomes larger than the reference speed. The arrow length setting unit 56 sets the length L of the arrow to a shorter length when the speed detected by the speed sensor 9 becomes smaller than the reference speed. By setting in this way, when the speed changes, the change in the time required to travel the distance corresponding to the length of the displayed arrow becomes small, and it is easy to drive.

  The corner processing unit 60 prevents an arrow from being bent at an intersection or the like and overlapping an invisible road behind the building so as not to be seen. For example, when there is a turning angle of a predetermined angle or more at a point within the length L set along the searched route (for example, 50 m ahead), the turning angle processing unit 60 calculates the length L of the arrow from the current position to the turning angle. Is temporarily reset to a distance up to (for example, 50 m) or a distance longer than that (for example, 55 m). By doing so, when the turning angle is closer than the distance L, the arrow appears to overlap only with the road that is visible in the forward field of view, and the visibility is improved. When the vehicle 22 approaches the corner, the corner processing unit gradually returns the length of the arrow, and returns the length of the arrow to the original set length when the corner is bent.

  FIG. 6 shows an example of an arrow displayed on the windshield display unit 15. The start point reference points A-1 to A-4 are points that appear to overlap the arrow starting point 34, and the end point reference points B-1 to B-4 are points that appear to overlap the arrow end point 36. Hereinafter, the case where the distance L to the target position is 180 m will be described. An intermediate reference point is set every 10 m in the arrow.

  FIG. 6A shows that there is no corner to bend up to 180 m ahead and it should continue straight. The arrow shown in FIG. 6B is a straight line up to the middle reference point of 16 sections, and the remaining two sections are formed with a curve and a left turn side straight line together with an end point reference point B-2. This indicates that you should turn left 160m ahead. The arrow shown in FIG. 6 (c) indicates that a right turn should be made 40m ahead. In this case, the corner processing unit 60 compresses an arrow farther than 40 m out of the set length of 180 m. The arrows shown in FIG. 6 (d) indicate the traveling direction of a branch point with good visibility such as an expressway. There is a branch at the reference point in the 8th section, indicating that it should get off the main line.

  When the map data of the CD / DVD driver 5 includes road inclination information, the slope processing unit 61 changes the positional correspondence between the arrow 32 and the ground 20 due to the inclination of the vehicle 22 when the vehicle 22 approaches the slope. Adjust. The slope processing unit 61 reads the inclination angle of the vehicle with respect to the horizontal plane detected by the gyro sensor 10. In particular, information indicating up / down in the direction along the traveling direction of the vehicle, that is, the angle in the pitch direction is read.

FIG. 1 is a block diagram showing a configuration of a car navigation system. FIG. 2 shows the configuration of the arrow drawing device 13. FIG. 3 shows the relationship between the driver, the vehicle, and the ground. FIG. 4 shows the windshield display 15. FIG. 5 is a flowchart showing the initial adjustment operation. FIG. 6 shows an example of an arrow.

Explanation of symbols

DESCRIPTION OF SYMBOLS 13 ... Arrow drawing device 14 ... Arrow projection device 20 ... Ground 22 ... Vehicle 24 ... Windshield 28 ... Eye 30 ... GPS receiver installation position 32 ... Arrow 34 ... Arrow start point 36 ... Arrow end point 38 ... Film 40 ... Polarizing plate

Claims (10)

A position information generator that generates position information indicating the current position of the vehicle;
A route calculator that generates route information indicating the route to the input destination;
Using the route information, a target position calculation unit that calculates a target position that is a predetermined distance ahead from the current position along the route from the current position;
A screen for overlaying an image on a front view of the vehicle for the driver of the vehicle;
A guide line drawing unit that draws the guide line image having a position that overlaps the current position on the ground in the forward view as one end and a position that overlaps the target position as the other end when viewed from the eye position;
A car navigation system comprising: a projection unit that projects the guide line image on the screen. The car navigation system according to claim 1,
A vehicle speed sensor for detecting the speed of the vehicle;
A car navigation system comprising: a guide line length setting unit that sets the predetermined distance longer as the speed increases. The car navigation system according to claim 1 or 2,
Furthermore, a display screen for displaying a map,
A first input device for designating a calibration point which is a position in the map;
A calibration video drawing unit for creating a calibration video designating a calibration position on the screen,
The projection unit projects the calibration image onto the screen,
A second input device for setting a setting position of the calibration image projected on the screen;
The guide line drawing unit adjusts the position of the guide line image using the set position. A car navigation system according to claim 3,
The calibration image, when viewed from the eye position at a preset reference position, has a position that overlaps the current position on the ground in the front view as one end and a position that overlaps the calibration position as the other end. A car navigation system that includes a line. The car navigation system according to any one of claims 1 to 4,
And a gyro sensor for detecting an inclination angle of the vehicle with respect to a horizontal plane.
The guide line drawing unit adjusts the position of the guide line image using the set position. The car navigation system according to any one of claims 1 to 5,
Further, when the target position is located farther than the turning angle in the route, the distance from the current position to the target position is temporarily longer than the predetermined position until the current position approaches the turning angle. A car navigation system comprising a corner processing section for resetting the target position so as to be shortened. The car navigation system according to any one of claims 1 to 6,
The screen is
A transparent film,
A plurality of polarizing plates installed in the film, having a gap between them and having the same polarization direction,
The projection unit projects the guide line image onto the screen with light having a polarization direction different from that of the polarizing plate. In a head-up display screen in which an image is projected on the windshield of a vehicle,
A film disposed on the windshield;
A plurality of polarizing plates arranged uniformly and dispersed in a predetermined region on the film,
The average visible light transmittance in the predetermined region is 70% or more. Head-up display screen. A transparent film installed between the eyes of the driver of the vehicle and the forward view of the vehicle;
A screen for a head-up display, comprising: a plurality of polarizing plates installed on the film, having a gap between them and having the same polarization direction. A head-up display screen according to claim 8 or 9,
A projection unit,
The plurality of polarizing plates have the same polarization direction,
The car navigation system, wherein the projection unit projects an image for guiding a traveling direction of the vehicle onto the head-up display screen with light having a polarization direction different from that of the polarizing plate.

Images