TWI420074B - Method of using road signs to augment global positioning system (gps) coordinate data for calculating a current position of a personal navigation device and related personal navigation device - Google Patents

Description

Method for calculating the location of a personal navigation device using road signposts to assist global positioning system coordinate data and related personal navigation devices

The present invention provides a method and a related personal navigation device for performing a map comparison and estimation positioning technique using a one-person navigation device, and more particularly to using one of the recognizable road signs to know the position of the global positioning system coordinate data to calculate a person navigation device. One of the locations is more precise.

The Global Positioning System (GPS) is the most basic function built into the personal navigation device known to the public, and is widely used in personal navigation devices. A common function of personal navigation devices is to provide a map database analysis to generate appropriate navigation commands and display the instructions on the screen of the personal navigation device. This type of personal navigation device is typically attached to the front dashboard of the vehicle with a suction cup or other type of fastening element.

A personal navigation device generally refers to a device that can guide a user to a predetermined destination. Such devices typically have a built-in system that can receive positioning data, such as a global positioning system receiver, or may only be in communication with a receiver that has the capability to receive positioning data. There are several methods for analyzing data by such devices, one is a data that can be self-operated by the route; the other is a remote server connected to a path data computing function, and the server operates and provides navigation data; Or the device not only has its own computing function, but also can be connected to the remote server to receive the computing data of the server. The handheld GPS personal navigation device does not need to be completely fixed in the transportation vehicle, but can be easily disassembled by the user. Such personal navigation devices usually (but not necessarily) have built-in GPS antennas, navigation software and maps, and can draw and display maps themselves, which can be a completely independent device.

The estimated positioning method is a technique for analyzing the previously known position to estimate the position, and can further analyze the known speed, time-consuming and path direction to obtain more accurate positioning coordinates. In the GPS navigation device, the application of the estimated positioning method can continuously maintain the navigation function when the satellite signal of the global positioning system is not received, or when the positioning and navigation capability of the global positioning system fails. For example, when driving through some areas that are unable to receive radio waves in the atmosphere, personal navigation devices will not be able to download data from satellites, such as in tunnels; or when driving through densely populated urban jungles; GPS receiving The device may also calculate incorrect navigation messages due to interference, such as in a metropolis.

In addition to the above-mentioned GPS satellite reception quality failure conditions, it is also possible that the accuracy of the global positioning system coordinate data is not sufficient to identify some precise locations of the personal navigation device, for example, equipped A vehicle with a personal navigation device travels on one of two very close parallel roads, however, the coordinate data of the GPS satellite received by the personal navigation device will have significant errors in the area, resulting in The personal navigation device cannot accurately determine which road the vehicle is on.

In order to overcome the lack of reliability of the global positioning system coordinate data in the above several items, it is urgent to develop a method that can use other techniques to perform map comparison and estimation positioning.

The present invention provides a method for using a known location road sign to assist global positioning system coordinate data received by a GPS receiver built into a personal navigation system, thereby calculating a location of the personal navigation device and associated personal navigation device. The above problem.

The present invention provides a method of using road signage to assist global positioning system coordinate data to calculate the location of one of the personal navigation devices. The method includes using the personal navigation device to obtain an up-to-date global positioning system coordinate data; using the personal navigation device to obtain an image on a camera, the image is a road through which the personal navigation device passes and its surrounding environment image; The image performs image processing to identify a road sign on the image; and determines an actual location of the personal navigation device based on the known location of the landmark and the latest global positioning system coordinate data.

The present invention further provides a personal navigation device that uses road signage to assist a global positioning system coordinate data to calculate the location of one of the person navigation devices. The personal navigation device includes a global positioning system receiver for receiving the latest global positioning system coordinate data; a camera for capturing an image of the personal navigation device traveling to a surrounding area of the road; and a processor for The image performs image processing to identify a road sign within the image and assists the latest global positioning system coordinate data to determine the actual location of the personal navigation device based on a known location of the road sign.

Initially, in order to calculate the location of the personal navigation device by triangulation, the personal navigation device can only rely on receiving global positioning system coordinate data from the satellite of the global positioning system. But as the sales of personal navigation devices continue to increase, more and more new features are beginning to increase. In the present invention, the personal navigation device will be equipped with a camera so that the personal navigation device can not only analyze the data downloaded from the satellite, but also analyze the visual signal captured from the camera to improve the positioning ability of the personal navigation device to identify the location. .

Please refer to FIG. 1. FIG. 1 is a functional block diagram of a person navigation device 10 according to the present invention. The personal navigation device 10 includes a global positioning system receiver 12 for receiving satellite signals of the global positioning system and calculating relevant coordinate data and then estimating the location of the personal navigation device 10. The personal navigation device 10 further includes a display 14 and a speaker 16 for allowing the user to read and analyze the completed data by visual images and audio signals. The personal navigation device 10 further includes a camera 18 for capturing images and interpreting road signs within the images. For example, like a digital camera or video recorder. When the personal navigation device 10 is installed by the transportation tool, the image captured by the camera 18 captures the information of the road passing through the transportation vehicle and the surrounding environment, so that the camera 18 can obtain the two bypass signs located on the road. In addition, the camera 18 may be a digital camera capable of capturing images at a specific time point or a predetermined time, or may be a digital video recorder having a continuous recording function. The personal navigation device 10 further includes a processor 20 that can be used not only to control the internal operation of the personal navigation device 10, but also to perform image processing calculations on the images captured by the camera 18. The processor 20 can be any processor that conforms to a functional specification, such as a Digital Signal Processor or a Central Processing Unit, and can also replace a single core processor with a multi-core processor. The personal navigation device 10 can also store a landmark database 22 in the built-in memory. The road sign database 22 stores a plurality of road signs and their corresponding position information and feature information, and the position of each road sign can be expressed by latitude and longitude coordinates. In the road sign database 22, all the feature information of each road sign is stored, including a road sign pattern, a road sign shape, a road sign color, a road sign text, or a road sign arrow. These feature information and landmarks of known locations can be used by the personal navigation device 10 to compare with the landmarks stored in the landmark database 22.

Please refer to FIG. 2. FIG. 2 is a schematic diagram of a transportation vehicle 32 passing through a road 30 and a road sign 34 disposed beside the road 30. The personal navigation device 10 can be installed where the vehicle 32 is near the front windshield, so that the camera 18 equipped with the personal navigation device 10 can capture images of the road 30 and its surroundings. When the vehicle 32 approaches the road sign 34, the camera 18 will capture an image containing the road sign 34. Each time the camera 18 takes an image, the processor 20 will make an instant image of each image. Like processing operations, and using identification techniques to analyze whether there are any road signs on the image. Referring to FIG. 2 again, when the processor 20 determines that the image captured by the camera 18 contains the landmark 34, the processor 20 analyzes all the feature information of the landmark 34 and compares it with the plurality of landmarks stored in the landmark database 22. Correct. As described above, the road sign 34 has a number of different feature information to be compared. For example, the road sign 34 may be rectangular, triangular, or octagonal, and will be used with the plurality of road signs in the landmark database 22. For comparison; the color of the road sign 34 may be red, green, blue, yellow, white, orange, or color, and is used to compare the color information of the plurality of road signs stored in the landmark database 22; The pattern of the road sign 34 may be a pattern such as careful falling stone, paying attention to the schoolchildren, and the road is not connected, and will be used to compare with the pattern information of the plurality of road signs stored in the road sign database 22; the road sign 34 has other characters such as words and arrows. And other features will be compared with the stored data of the road sign database 22.

The road sign 34 can also be identified by comparing the location calculated by the personal navigation device 10 with the known location road sign stored in the landmark database 22. For example, if the road 30 through which the vehicle 32 passes is a straight section of a highway that crosses the farmland, there may be only one (or fewer) road signs per kilometer on this path. When the image taken by the camera 18 is analyzed for the road sign 34, the location of the transportation vehicle 32 can be confirmed by the road sign 34. When the global positioning system coordinate data provided by the global positioning system receiver 12 has an error of up to 100 meters, the traffic sign 32 can be accurately positioned by means of a road sign 34 stored in a known location in the landmark database 22. position.

Another useful function of the present invention is to perform a computational positioning calculation. Referring to FIG. 2, it is assumed that the vehicle 32 is traveling in the tunnel and the GPS device built into the personal navigation device cannot receive any satellite signals of the global positioning system. At this time, the processor 20 can simultaneously use the global positioning system. The latest global positioning system coordinate data received by the receiver 12 and the positioning information obtained through the identification road sign 34 are used to perform the calculation. For example, assuming that there is a tunnel of two kilometers long and the road sign 34 is just in the center, when the information of the road sign 34 has been stored in the landmark database 22, the personal navigation device can obtain the road sign by scanning the landmark database 22. The correct position of 34. Therefore, even if the personal navigation device 10 cannot receive the global positioning system coordinate data in the tunnel, the location information of the transportation vehicle 32 can be obtained by instantly recognizing the road sign 34.

In addition to performing the estimated positioning method, the present invention also employs a graphical comparison technique. The function of the graphical alignment technique is that the graphical alignment technique can help the personal navigation device 10 determine the correct location when there are several possible locations for the initial calculation. Please refer to FIG. 3, which is a schematic diagram of a road sign 60 of the present invention placed on a checkerboard path, wherein the road sign 60 is used to help identify the location of the vehicle 32. In Fig. 3, the roads 50, 52, 54 are east-west roads and are substantially parallel to each other, while the roads 56, 58 intersecting there are north-south roads, and the traffic vehicle 32 is assumed to be on the road 52. Drive eastward. Since the coordinate data of the global positioning system is not accurate, the personal navigation device 10 mounted on the transportation vehicle 32 cannot determine whether it is located on the road 52, 54, or 56, especially when the possible roads are parallel to each other and close to each other. The possibility of such misjudgment is greatly increased. Therefore, when the vehicle 32 travels close to the intersection P2 of the north-south road 56, the personal navigation device 10 cannot interpret that the vehicle 32 is located at the intersection P1, P2, or P3; thus, it can be seen that the personal navigation device will A wrong navigation command is provided to the transportation tool 32. Assuming that the vehicle 32 is traveling on the road 52 and continues eastward, the vehicle 32 will pass a road sign 60 near the fixed point P4. Therefore, when the personal navigation device 10 captures the image containing the road sign 60 and transmits the plurality of road signs stored in the comparison sign database 22, the road sign 60 can be recognized and the position information can be obtained. More importantly, this technique enables the personal navigation device 10 to recognize that the vehicle 32 is located on the road 52, rather than on the roads 54, 56. Then, when the transportation vehicle 32 approaches the north-south road 58 located at the intersection P6, the personal navigation device 10 gives the driver appropriate navigation instructions. Therefore, the personal navigation device 10 can know that the approaching intersection is P6 by the identification of the landmark 60, instead of the intersection P5 or the intersection P7.

Please refer to FIG. 4, which is a schematic diagram of the road signs 80, 82, and 84 of the present invention disposed above a multi-lane highway 70. When the vehicle 32 is traveling on the highway 70 and approaching the road signs 80, 82, 84, not only can the personal navigation device 10 be correctly determined to be in the correct position on the highway 70 by recognizing the features of the road signs 80, 82, 84. It is also possible to analyze by road signs 80, 82, 84 which of the lanes on which the means of transport 32 is located on the highway 70. This function can direct the vehicle 32 to travel on the correct path to reach its destination when the multi-lane highway 70 branches off a number of branches in a certain section. For example, assume that left lane 72 is to destination A, center lane 74 is to destination B, and right lane 76 is to destination C. When the camera 18 captures an image containing the road signs 80, 82, 84, the personal navigation device 10 can determine that the transportation vehicle 32 is located on the highway 70 by comparing the relative positions of the road signs 80, 82, 84. Above the line. If the user's destination is A However, when the line 74 is driven, the personal navigation device issues a command to switch the lane and move to the lane 72 to alert the driver. In order for these functions to function more smoothly, the personal navigation device 10 must be installed in a position that ensures that the camera 18 is directly in front of the vehicle 32 and that has a positive, unbiased viewing angle.

In summary, the present invention installs a camcorder on a personal navigation device to obtain peripheral images of the roads it passes, and to assist the received global positioning system coordinate data, so that the personal navigation device can more accurately determine the location. The personal navigation device of the present invention not only uses landmark image analysis to determine the actual location of the personal navigation device, but also alerts the driver to the correct route without getting lost.

The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should be within the scope of the present invention.

10. . . Personal navigation device

12. . . GPS receiver

14. . . monitor

16. . . speaker

18. . . Camera

20. . . processor

twenty two. . . Road sign database

30. . . the way

32. . . Transportation

34. . . Road sign

50, 52, 54. . . the way

56, 58. . . North-south road

60. . . Road sign

P1, P2, P3, P5, P6, P7. . . intersection

P4. . . Fixed point

70. . . highway

72, 74, 76. . . Line

80, 82, 84. . . Road sign

1 is a functional block diagram of a personal navigation device of the present invention.

Figure 2 is a schematic view of the transportation vehicle of the present invention passing through the road and the road sign is placed beside the road.

Figure 3 is a schematic view of the road sign of the present invention seated on a checkerboard path.

Figure 4 is a schematic view of the road sign of the present invention placed above the multi-lane highway.

10. . . Personal navigation device

12. . . GPS receiver

14. . . monitor

16. . . speaker

18. . . Camera

20. . . processor

twenty two. . . Road sign database

Claims (22)

A method of using road signage to assist global positioning system coordinate data to calculate a location of a person's navigation device, comprising: obtaining an up-to-date global positioning system coordinate data using the personal navigation device; using the personal navigation device to obtain a camera An image obtained by the personal navigation device passing through a road and its surrounding environment image; performing image processing on the image to identify a road sign on the image, thereby obtaining position information represented by the latitude and longitude coordinates of the road sign; And determining an actual location of the personal navigation device based on the known location of the one of the landmarks and the latest global positioning system coordinate data. The method of claim 1, wherein the road sign is stored in a road sign database, and the road sign database includes a plurality of road signs and corresponding position information and feature information. The method of claim 2, further comprising identifying the road sign by comparing the shape of one of the road signs to the shape of the plurality of road signs in the road sign database. The method of claim 2, further comprising identifying the road sign by comparing the color of one of the road signs to the color of the plurality of road signs in the road sign database. The method of claim 2, further comprising patterning the one of the road signs and the road sign The pattern of the plurality of road signs in the library is used to identify the road sign. The method of claim 2, further comprising identifying the road sign by comparing the text of the road sign with the text of the plurality of road signs in the road sign database. The method of claim 2, further comprising identifying an arrow by an arrow of the road sign and an arrow of the plurality of road signs in the road sign database. The method of claim 2, further comprising comparing the possible location of the personal navigation device and the location of the plurality of landmarks in the landmark database based on the latest global positioning system coordinate data to identify the location Road sign. The method of claim 1, wherein determining the actual location of the personal navigation device based on the known location of the landmark and the latest global positioning system coordinate data comprises a plurality of pre-judgment locations calculated by the personal navigation device And determining the actual position of one of the personal navigation devices by comparing the known location of the road sign with the plurality of pre-judgment positions calculated by the personal navigation device. The method of claim 1, further comprising performing a calculated positioning calculation using the known location of the landmark when the personal navigation device is unable to receive the GPS signal. The method of claim 1, wherein the camera is a camera capable of capturing continuous images Camera. A personal navigation device that uses road signage to assist in calculating a location by a global positioning system coordinate data, comprising: a global positioning system receiver for receiving the latest global positioning system coordinate data; a camera And is a processor for performing image processing on the image to identify a road sign in the image, thereby obtaining the road sign by the road sign; The position information is represented by the latitude and longitude coordinates, and the latest global positioning system coordinate data is assisted according to a known position of the road sign to determine the actual position of the personal navigation device. The personal navigation device of claim 12, further comprising a road sign database, wherein the road sign database comprises a plurality of road signs and corresponding location information and feature information. The personal navigation device of claim 13, wherein the processor is configured to identify the road sign by comparing the shape of one of the road signs with the plurality of road signs in the road sign database. The personal navigation device of claim 13, wherein the processor is configured to identify the color of the one of the road signs and the color of the plurality of road signs in the landmark database. The road sign. The personal navigation device of claim 13, wherein the processor is configured to identify the road sign by comparing the pattern of one of the road signs with the pattern of the plurality of road signs in the road sign database. The personal navigation device of claim 13, wherein the processor is configured to identify the road sign by comparing the text of the road sign with the text of the plurality of road signs in the road sign database. The personal navigation device of claim 13, wherein the processor is configured to identify the road sign by comparing an arrow of the road sign with an arrow of the plurality of road signs in the road sign database. The personal navigation device of claim 13, wherein the processor is configured to compare a possible location of the personal navigation device derived from the latest global positioning system coordinate data with the plurality of road signs in the landmark database The location to identify the road sign. The personal navigation device of claim 12, wherein the processor is configured to calculate a plurality of pre-judgment positions based on the latest global positioning system coordinate data, and compare the calculated position with the calculated position The plurality of pre-judgment locations are derived to determine the actual location of the personal navigation device. The personal navigation device of claim 12, wherein when the global positioning system receiver is unable to receive the global positioning system signal, the processor is configured to perform a calculated positioning calculation using the known position of the landmark. The personal navigation device of claim 12, wherein the camera is a camera that captures continuous images.