Navigation device for displaying an approaching intersection

Data processing: vehicles – navigation – and relative location – Navigation – Employing position determining equipment

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C340S995190, C701S207000

Reexamination Certificate

active

06473693

ABSTRACT:

FIELD OF THE INVENTION
The present invention relates to a navigation device which performs a 3 dimensional display.
BACKGROUND OF THE INVENTION
FIG. 16
is a block diagram of a conventional navigation device. In the figure,
110
is a CPU (central processing unit) which performs various types of calculations. The CPU controls the vehicle position detection means
110
A which detects the vehicle position on the basis of signals from a sensor or a GPS receiver, a route searching means
110
B which searches a route to a destination from a detected vehicle position and a display conversion means
110
C which converts route data read from a CD-ROM to bird's eye view data from a fixed viewpoint.
111
is a ROM (read on memory) which stores a program for various calculations performed by the CPU
110
,
112
is a memory (DRAM) which stores calculation results and the like from the CPU
110
or data from a bearing sensor, distance sensor, GPS receiver, CDROM driver or the like.
113
is a backup memory (SRAM for preserving necessary data in the event of a power supply termination to the main device.
114
is a memory (Chinese characters, font ROM) which stores patterns such as signs or letters for display on the crystal display.
115
is an image processor for forming a display image based on map data or the vehicle present position.
116
is a memory (VRAM) which composes map data output from the CPU
110
, present position data and Chinese characters, town names output from the font ROM
114
and fonts and Chinese characters for road names or the like and stores images displayed on the crystal display.
117
is a RGB conversion circuit for converting output data from the VRAM
116
to color data. The color signals are output from the RGB conversion circuit
117
to the crystal display.
118
is a communication interface.
The operation of the invention will be explained next.
FIG. 17
is a flowchart showing the operation of a conventional navigation device.
In a step ST
1601
, a display angle &thgr;x of the bird's eye view map which displays the distance from the vehicle position to the intersection. In a step ST
1602
, a bearing is determined from road network data read from a CD-ROM and the vehicle position. Conversion is performed to a bird's eye view map at the angle &thgr;x calculated in a step ST
1601
and an enlarged screen is prepared so that the direction of progress is in an upward direction. In a step ST
1603
, it is determined whether an intersection has been reached and in the event that the intersection has been reached, the routine is terminated.
Steps ST
1601
,
1602
,
1603
are repeated as shown in
FIG. 17
until an intersection is reached from a current vehicle position. The angle &thgr;x approaches 0 as the vehicle position approaches the intersection. When the vehicle position is distant from the target intersection, the viewpoint is low, and as shown in FIG.
18
(
a
), the display range is wide. However as the vehicle approaches the target intersection, the viewpoint rises, and as shown in FIG.
18
(
b
), the display range narrows to express the distance in an easily understandable form. Furthermore when the vehicle position has almost reached the intersection, the viewpoint is roughly above the target intersection and becomes a bird's eye view map as shown in FIG.
18
(
c
).
As the conventional navigation device is constructed as above, the display range narrows as the intersection is reached. For example, when the difference between direction in which the vehicle is travelling and the direction to the position of the intersection is great, the problem has arisen that it has not been possible to display the intersection.
The present invention is proposed to solve the above problems and has the object of providing a navigation device which can display an intersection even when there is a great difference the direction in which the vehicle is travelling and the direction to the position of the intersection.
DISCLOSURE OF THE INVENTION
The navigation device of the present invention is a navigation device which performs a 3 dimensional display when approaching an intersection. The navigation device comprises a direction of travel detection means which detects the direction-of-travel of the vehicle, a direction-to-intersection detection means which calculates the difference between the direction of travel of the vehicle and the direction to the position of the intersection, a viewpoint direction calculation means which detects the direction of the viewpoint in order to perform 3 dimensional display based on the difference between a detected direction of vehicle travel and a calculated direction, and a display means which performs display based on a calculated viewpoint direction.
As a result of this arrangement, even when the difference between the direction in which the vehicle is travelling and the direction to the position of the intersection is great, it is possible display the intersection.
The navigation device of the present invention is a navigation device which performs a 3 dimensional display when approaching an intersection. The navigation device comprises a vehicle position detection means which detects a vehicle position, an intersection distance calculation means which calculates a distance from a detected vehicle position to an intersection, a viewpoint position calculation means which calculates the height of the viewpoint so that the height of the viewpoint for the purposes of 3 dimensional display is reduced as the distance from the calculated vehicle position to the intersection is reduced, and a display means which carries out a display based on the calculated viewpoint height.
As a result of the above arrangement, it is possible to create a more realistic appearance of approaching the intersection.
The navigation device according to the present invention is adapted to perform three dimensional display on approaching an intersection. The navigation device is provided with a traffic signal disposition means which disposes a traffic signal at a position which is close to an actual position on an intersection when an intersection is determined to exist in a direction of vehicle travel, and a display means which displays a traffic signal on a disposed position.
The navigation device of the present invention is a navigation device which performs a 3 dimensional display when approaching an intersection. The device comprises a road existence determination means which determines whether or not a road exists on the left side as seen from the direction in which the vehicle is travelling at the intersection, a signal mechanism disposal means which disposes a signal mechanism at a position facing the direction of right turn in the road in the vicinity of the intersection when a road is determined to exist, and which disposes a signal mechanism at a position facing the direction of left turn in the road in the direction in which the vehicle is travelling in the vicinity of the intersection when a road is determined to not exist, and a display means which carries out a display which disposes a signal mechanism at a disposed position.
As a result of the arrangement above, it is possible to perform a 3 dimensional display at the intersection in a realistic form.
The navigation device of the present invention is a navigation device which performs a 3 dimensional display when approaching an intersection. It comprises a signal generation means which a right-hand or a left-hand signal at the intersection when the vehicle approaches an intersection which turns left or right, a road width correction means which corrects a road width of roads crossing intersections other than the target intersection when the vehicle approaches a right or left turning intersection, a display means which displays a generated signal on an intersection and which displays intersections other than the target intersection with a corrected width.
By the above arrangement, it is possible to recognize a right or left turning intersection without errors.


REFERENCES:
patent

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Navigation device for displaying an approaching intersection does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Navigation device for displaying an approaching intersection, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Navigation device for displaying an approaching intersection will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2970173

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.