JPH04249714A - On-vehicle navigation apparatus - Google Patents

Abstract

PURPOSE:To accurately navigate a vehicle after it returns to an aimed course. CONSTITUTION:The output of a gyro sensor (direction sensor) 1 is input to a CPU 4 via an A/D converter 3. A speed sensor 2 for detecting the running distance integrates outputs thereof per sufficiently short time and inputs to the CPU 4 via the A/D converter 3. The CPU 4 executes a predetermined navigation algorithm in accordance with a program written in a ROM 6 with the use of data, etc., of a RAM 5 or a memory card 9 inserted in a socket 8. The result is displayed by a display device 7. The operator inputs various kinds of operational instructions through an operating part. An instruction to start navigation is also commanded through the operating part.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an on-vehicle navigation system, and more particularly to an on-vehicle navigation system that corrects the position of the vehicle on a predetermined course.

0002

[Prior Art] There are two types of in-vehicle navigation devices: self-contained and heteronomous types. The self-contained type is equipped with a distance sensor and a direction sensor in the vehicle, and estimates the vehicle's position while obtaining data on direction and distance. This is a method to do so. The heteronomous type is a method that estimates the location by receiving location information from an external source other than the vehicle via radio waves. In any of these methods, the in-vehicle navigation device has a configuration in which map data stored in a CD-ROM or the like is displayed on an image display device, and the current position and destination of the vehicle are displayed on this image map. It has become. However, it is necessary to create a database of all the maps of the vast area where vehicles may travel, which requires a huge amount of time and effort, and the map data may be inaccurate or If the road inside is not included in the map data, it may cause malfunction. Furthermore, roads may be newly constructed one after another, or may be changed due to land readjustment, etc., and there is a problem in that the database needs to be corrected each time. From this point of view, a system has already been proposed that performs navigation by converting a planned travel course into data using a digitizer or the like, without preparing map data in advance. In such a system, as shown in FIG. 9, if the CDEF's planned driving course is converted into data using a digitizer and input into the navigation device, and the vehicle departs from C, a point M1 is generated at a position a predetermined distance CM1, Compare this with the position of the dead reckoning point R1 calculated by dead reckoning, and if the deviation in the position is within a predetermined value, correct it by replacing R1 with the coordinates of M1, and if the deviation is larger than the predetermined value, change the planned running course. Processing is performed to indicate that it has come off. Similar operation is performed for M2 with R2
, M3 to R3, and so on.

0003

[Problems to be Solved by the Invention] However, in the above-mentioned conventional in-vehicle navigation device, once the user deviates from the scheduled driving course, processing for deviating from the scheduled driving course is executed, so even if the user returns to the scheduled driving course, the input This has the disadvantage that navigation cannot be performed based on the data of the planned travel course, and the data is wasted. Furthermore, after correcting the dead reckoning point to the planned course, it was not determined whether the correction was correct or not, resulting in the drawback that the navigation accuracy was not sufficient. It is an object of the present invention to solve the drawbacks of such conventional in-vehicle navigation devices.

0004

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a system in which a planned running course is input and set in advance as a plurality of continuous vectors connecting a plurality of points set as necessary. An in-vehicle navigation device that provides guidance based on a course includes a direction detecting means for detecting the traveling direction of the vehicle, a distance detecting means for detecting the traveling distance of the vehicle, and detection results from the direction detecting means and the distance detecting means. a means for performing dead reckoning based on;
If the deviation of the point obtained by dead reckoning from the planned running course is within the permissible range, the dead reckoning point is corrected to be on the planned running course, and the deviation of the position obtained by dead reckoning from the planned running course is within the permissible range. If the above correction is not made and the vector connecting the dead reckoning points calculated after that is close to and approximately parallel to any vector forming the planned course, the plan is to run at that dead reckoning point. A dead reckoning that is corrected on the course, and then compared with the corresponding vector of the planned course by comparing the multiple vectors sequentially obtained by dead reckoning, and if the directions match at least, then the vectors are corrected to the planned course first. The basic feature is that the device has a means for fixing the point at that position.

[0005]

[Operation] The direction of travel of the vehicle and the distance traveled by the vehicle are detected,
Dead reckoning is performed based on this detection result. If the deviation of the point obtained by dead reckoning from the scheduled running course is within the allowable range, the dead reckoning point is corrected to be on the scheduled running course. On the other hand, if the deviation of the position obtained by dead reckoning from the planned running course exceeds the allowable range, the correction is not made and the vector connecting the calculated dead reckoning points is an arbitrary vector that forms the planned running course. If the dead reckoning point is close to and approximately parallel to the planned running course, the dead reckoning point is corrected to the planned running course, and then the multiple vectors sequentially obtained by dead reckoning are compared with the corresponding vectors of the scheduled running course, and at least that direction is determined. If they match, the corrected dead reckoning point is determined at that position on the planned course.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, a gyro sensor is used as a direction sensor 1 in this embodiment, and the output thereof is input to a CPU 4 via an A/D converter 3. The speed sensor 2 is for detecting the distance traveled by the vehicle, and is configured to calculate the distance traveled by integrating the outputs of the speed sensor every sufficiently short unit time. This output is also sent to the CPU 4 via the A/D converter 3.
is configured to input. CPU4 is ROM6
A predetermined navigation algorithm is executed according to a program written in the memory card 9 using the data stored in the RAM 5 or the memory card 9 inserted into the socket 8. The result is then displayed on the display 7. The user inputs various operation commands through the operation section, and the navigation start command is also configured to be issued through this operation section. The user uses a digitizer or the like to input the planned driving courses G1 to G7 to the CPU 4 as shown in FIG. 3, and this input value is stored in the memory card 9. Or instead of this, use a memory card 9
It is also possible to enter the planned driving course in advance and select the actual driving course from among them. During navigation, the signal from the direction sensor 1 and the speed sensor 2 and the planned driving course recorded in the memory card 9 are compared, and the turning direction is displayed on the display 7 as shown in FIG. 2 with an arrow, or the direction is set. The device is configured to display a message indicating that the vehicle has veered off the road. The CPU 4 is configured to perform dead reckoning based on data detected from the direction sensor 1 and speed sensor 2, calculate the current position of the vehicle, and compare this with the planned course. To explain this using FIG. 3, first click point G1
When the dead reckoning position is compared with the shape point S1 at the point H0 starting from , the deviation between the positions of H0 and S1 is small and within the allowable range, so H0 is corrected to S1. Next, when the vehicle moves to point H1, the deviation from the planned driving course exceeds the allowable range, so H
1 is not corrected to S1, and only the comparison between H2, H3, H4, and H5, dead reckoning, and the planned running course is performed. Then, if it is determined that the distance between G1 and G2 becomes smaller at the point H6 and the direction at H6 and H7 matches that of G1 and G2, the position of H7 is corrected to S2, and from then on, the position of H7 is changed to H9, H10, H11, and H12 again. We will perform dead reckoning and correct the position to the planned course. and,
It is confirmed whether or not the modification of H7 to S2 is correct, as shown in FIGS. 4 to 6. That is, the S3-G3 vector and H10-H11 vector, the G2-S3 vector and H9-H10 vector, the S2-G2 vector and H8
-H9 vectors are compared, and if these vectors match, it is determined to be a correct match. In Figure 7, the vector H6-H7 is G1-
An example is shown in which H7 is not corrected by S2 because it does not match the vector of G2 or is not within a predetermined position. In this case, the H7-H9 vector and G2-S2 vector, the H9-H10 vector and G2
-S3 vector, H10-H11 vector and S3-
Calculate the degree of coincidence of the three consecutive vectors of G3. If it is not determined to be a match, then H9-H
10 vector and G2-S3 vector, H10-H1
1 vector, S3-G3 vector, and H11-H1
The three degrees of coincidence between the vector 2 and the vector G3-G4 are calculated, and this is sequentially repeated. And if H10-H
11 vector, S3-G3 vector, and H11-H1
If the vector 2 matches the vector G3-G4, and the vector G4-G5 matches the vector H12-H13, then H
13 is modified to G5 to become H14, which is configured to match the scheduled course.

Next, the operation will be explained based on FIG. In the map matching calculation, a polygon that sets a probability area is generated for each unit time from the dead reckoning point (step 20), and the area of this polygon expands in proportion to the time or distance traveled if it deviates from the planned course. It is set to continue. Then, it is determined whether or not the planned running course within the area of this polygon is included (step 21), and if it is not included, map matching processing for areas other than the set course is executed (step 40). If included, it is then determined whether the direction of the dead reckoning and the direction of the planned running course match (step 22), and if they match, the dead reckoning point is corrected to a point on the planned running course (step 22). 23). Then, map matching processing on the planned course is performed (step 24), and it is confirmed whether the third click point or shape point has been passed (step 25). If it has passed, the degree of coincidence of the three vectors that have passed is calculated (step 26), and the judgment of coincidence is executed (step 2).
7). If they match, the recognition is determined to be correct (step 28), and if they do not match, the correction of the dead reckoning point in step 23 is canceled and map matching processing outside the planned course is executed (step 2).
9). If the direction of dead reckoning does not match the planned course in step 22, after detecting three turns (step 30), calculate the degree of coincidence of the three vectors (step 31), and if they match (step 3
2), proceed to step 23. If they do not match, it is checked whether the next new turning angle has been detected (step 33), and if detected, the previous oldest vector is discarded, a new vector is added, and the process returns to step 31 (step 34).

[0008] According to the configuration described above, when the vehicle deviates from the planned course and returns to the course, it becomes possible to perform appropriate navigation. In addition, since the configuration is configured to compare and confirm the vector calculated by dead reckoning after the position is corrected and the vector of the planned course, highly accurate navigation can be performed.

[0009]

[Effects of the Invention] As explained above, the in-vehicle navigation device of the present invention makes it possible to perform appropriate navigation when deviating from the planned driving course and returning to the same course, so that the input planned driving course can be changed. Nothing goes to waste. Further, since the configuration is configured such that after the position is corrected, the vector calculated by dead reckoning is compared and confirmed with the vector of the planned course, which has the effect of enabling highly accurate navigation.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a detailed view of the display.

FIG. 3 is an explanatory diagram of operation.

FIG. 4 is an explanatory diagram of operation.

FIG. 5 is an explanatory diagram of operation.

FIG. 6 is an explanatory diagram of operation.

FIG. 7 is an explanatory diagram of operation. FIG. 2 is an explanatory diagram of the operation of a conventional device.

FIG. 8 is a flowchart diagram for explaining the operation.

FIG. 9 is an explanatory diagram of the operation of the conventional device.

[Explanation of symbols]

1: Direction sensor, 2: Speed sensor, 3: A/D converter, 4: CPU, 5: RAM, 6: ROM, 7: Display, 8: Socket, 9: Memory card.

Claims (1)

[Claims] Claim 1: An in-vehicle navigation device in which a planned travel course is input and set in advance as a plurality of consecutive vectors connecting a plurality of points set as necessary, and guidance is provided based on the planned travel course. a direction detecting means for detecting the traveling direction of the vehicle; a distance detecting means for detecting the traveling distance of the vehicle; a means for performing dead reckoning based on the detection results from the direction detecting means and the distance detecting means; If the deviation of the point obtained by dead reckoning from the planned running course is within the permissible range, the dead reckoning point is adjusted to be on the planned running course. If the vector connecting the dead reckoning points calculated after that is close to and approximately parallel to any vector forming the planned running course, then the dead reckoning point is corrected to be on the planned running course. , then compare the multiple vectors sequentially obtained by dead reckoning with the corresponding vectors on the planned running course, and if at least the directions match, the dead reckoning point corrected earlier on the planned running course is moved to that position. An in-vehicle navigation device characterized by comprising: means for determining.