JPH083524B2 - GPS navigation device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a GPS navigation device for various mobile bodies, and for example, receives radio waves in a plurality of artificial satellites that constitute GPS. Even when the number of things that can be done is two or less, by utilizing the independent position data based on the moving direction data and the moving distance data of the moving body from the attached direction sensor and distance sensor, The present invention relates to a GPS navigation device capable of accurately detecting the current position of a moving body.

Further, according to the present invention, the GPS function unit and the self-supporting function unit are used together, and it is possible to prevent the occurrence of an error in the current position of the moving body when the GPS function unit is operating. It relates to a GPS navigation device.

[Prior Art] Transmitting radio waves from a plurality of artificial satellites to various moving bodies such as ships, aircrafts, automobiles, etc. in order to confirm or determine their current position, moving speed, etc. It has been noted that GPS positioning devices are useful. here,
A GPS positioning device is a global positioning system (Global Positioning System).
Ioning System) is to receive the radio waves from a plurality of artificial satellites that belong to the current position of the mobile.

As is conventionally known, a positioning operation performed using such a GPS positioning device is usually performed by receiving radio waves from three or four artificial satellites. With GPS, if the distances from three artificial satellites to a moving body are measured at the same time, the instantaneous position of the artificial satellite can be calculated from the orbital data sent from the artificial satellite. When the radius measured as is the radius, it is possible to measure the two-dimensional position (latitude, longitude) of the moving body at the intersection of the three spherical surfaces. On the other hand, when radio waves from four artificial satellites can be received, the three-dimensional position (latitude, longitude, altitude) can be measured. That is, GPS positioning becomes possible only after receiving radio waves from three or more artificial satellites, and the position of the moving body can be obtained. Radio waves from a plurality of artificial satellites are simultaneously received on the mobile body side, and there is a difference in accuracy between the timepiece device provided on the plurality of artificial satellites and the timepiece device provided on the mobile body side. After the required correction processing for the time shift based on the above is performed, the current position of the moving body is displayed on an appropriate display means. At this time, the necessary map information is superimposed on the information on the current position and displayed on the display means.

FIG. 7 shows, for example, Japan Radio Technical Report (1984, No. 2
This type of conventional GPS navigation device is shown, as shown in the article "GPS navigation device" on pages 16 to 23 of 4). In FIG. 7, (71) is a GPS antenna for receiving satellite radio waves, and the output side of the GPS antenna (71) is connected to the GPS receiving section (72). The pseudo range data obtained by the GPS receiving section (72) is introduced into the GPS positioning calculating section (73).
In this GPS positioning calculation section (73), accurate longitude, latitude and altitude are calculated based on the pseudo distance data described above, and as a result, the accurate current position of the moving body is detected. The data relating to the current position obtained in this way is stored in an appropriate data storage unit (not shown), and at the same time, in the display unit (74) including a display means such as a CRT, a map related to the related map is displayed. It will be displayed redundantly.

By the way, in order to perform the two-dimensional or three-dimensional positioning as described above, it is necessary to simultaneously receive radio waves from at least three or four artificial satellites belonging to the GPS. However, for example, in urban areas and mountainous areas, the presence of obstacles such as high-rise buildings and alpines makes it impossible for the radio waves from the required number of artificial satellites to reach the moving body at the same time, and GPS positioning may become impossible. Even if the GPS positioning is possible, the positioning accuracy may be significantly reduced due to the arrangement state of the artificial satellite with respect to the moving body and the attenuation due to the reflection of the radio waves by the obstacles described above. is there.

Further, some of the above-described GPS navigation devices for various moving bodies are provided with a self-supporting function unit in addition to the GPS function unit. By the way, unlike the GPS function unit, this self-supporting function unit can know its own current position based only on the data acquired by itself, without depending on external data such as radio waves from artificial satellites. It was made possible.

FIG. 8 is a block diagram showing a conventional GPS navigation device of this type. In FIG. 8, (81) is a GPS antenna for receiving satellite radio waves, and the output side of the GPS antenna (81) is connected to the GPS receiving section (82). (83) is a direction sensor, (84) is a distance sensor,
These are connected to the position detecting device (85) together with the output side of the GPS receiving section (82). The output side of the position detecting device (85) is connected to the data processing device (86), and the map data storage device (87) and the display device (88) are connected to the data processing device (86). Has been done.

Next, the operation will be described. An operator of a moving body such as a vehicle activates the above-described GPS navigation device by pressing a start key on a keyboard (not shown), for example. Here, either the GPS function unit or the self-supporting function unit is selected, but if radio waves from three or more artificial satellites are currently received, the GPS function unit is selected and the GPS antenna is selected. The current position of the moving body is confirmed or determined only by the satellite radio waves received in (81). On the other hand, when the GPS function unit cannot be selected due to the presence of various obstacles,
The self-supporting function unit is selected, and based on only the data acquired from the azimuth sensor (83) and the distance sensor (84), the current position and the moving direction of the self are confirmed and determined.

Now, it is assumed that the GPS function unit of the conventional GPS navigation device described above is selected. FIG. 9 is a diagram illustrating the operation of the conventional example in such a case. In FIG. 9,
The horizontal axis represents the moving distance D of the moving body and the elapsed time t, and the thin solid line (that is, the horizontal axis) also represents the moving path of the moving body. The vertical axis represents the deviation (error) E of the moving body from the current position.
Now, it is assumed that the GPS function unit is selected at time t ₀ . At this time, the moving body moves on the moving route while receiving satellite radio waves from the GPS antenna (81). For example, if a high-rise building exists as an obstacle, An error may be included in the display of the current position of the moving object due to failure to receive radio waves from satellites or reception of noise such as radio waves reflected by other objects. is there. That is, in FIG. 9, it can be seen that the moving body has largely deviated from its movement route, as can be seen in the time zones t ₁ −t ₂ , t ₃ −t ₄ and t ₅ −t _6. And such a phenomenon is called a jump phenomenon. Due to the current jump condition, the operator of the moving body may mistakenly recognize the current position of the vehicle and mishandle it to cause a serious accident.

[Problems to be Solved by the Invention] Since the conventional GPS navigation device is configured and operates as described above, for example, in an urban area or a mountain area,
Due to the existence of obstacles such as high-rise buildings and high mountains, the radio waves from the required number of satellites cannot reach the moving body at the same time, and the desired GPS positioning becomes impossible, or Even if the GPS positioning is possible, the positioning accuracy may drop significantly due to the placement of artificial satellites with respect to the moving body and the attenuation due to the reflection of radio waves by the obstacles described above. There was a problem. In addition, in the conventional GPS navigation device that uses both the GPS function unit and the self-supporting function unit, when the GPS function unit is selected, the current position may be misidentified due to radio interference, which may cause a serious accident. There was also a problem that there was.

The present invention has been made to solve the above problems. Even if GPS positioning is impossible or the positioning accuracy is deteriorated, the position data from the so-called self-supporting functional unit is used. By doing so, it is possible to accurately detect and determine the current position of the mobile unit.
The purpose is to obtain S navigation system. Further, comparing the self-supporting speed dependent data at a predetermined time point and the GPS type speed dependent data at the predetermined time point, when the comparison result is a predetermined value or more, the position of the mobile body by the self-supporting data is selected,
If the comparison result is less than or equal to a predetermined value, the position of the moving body is selected by GPS type data to perform accurate position data switching, the current position can be detected with high accuracy, and misjudgment of the current position due to a jumping phenomenon can be prevented. GPS
The purpose is to obtain navigation equipment.

[Means for Solving the Problems] A GPS navigation device according to the present invention includes a map data storage device for storing map data, a GPS receiving device for receiving radio waves from a plurality of artificial satellites belonging to GPS, and a GPS receiving device for receiving the radio waves. A GPS-type positioning calculation unit that obtains GPS-type data representing at least one of the velocity or acceleration and the position of the moving body based on the output signal, a self-standing detecting unit that detects a traveling direction and a traveling distance of the moving body, and the self-standing type Of the GPS type data, the self-sustaining position detecting means for obtaining self-standing data representing at least one of the velocity or acceleration and the position of the moving body as the self-standing data based on the traveling distance output from the detecting means. GPS-type speed-dependent data having at least one of the speed or acceleration of the moving body, and a small one of the speed or angular velocity of the moving body in the self-supporting data. Independent speed-dependent data having at least one, GPS-type speed-dependent data at a certain time point and the independent speed-dependent data at a time point corresponding to the time point are compared, and the comparison result is a predetermined value or more. In the case of selecting the position of the mobile body of the independent data, if the comparison result is less than a predetermined value, selecting means for selecting the position of the mobile body of the GPS type data, and the output from this selecting means. On the basis of the above, the display device is provided to display the position of the moving body so as to overlap the map data.

[Operation] According to the present invention, the output of the self-sustaining position detecting means determines whether to select the position data obtained from the self-sustaining position detecting means or the position data obtained from the GPS positioning calculation section. Comparing the self-supporting speed-dependent data consisting of the speed or acceleration of the moving body at a certain time point and the GPS-type speed dependent data consisting of the speed or acceleration of the moving body which is the output of the GPS-type positioning calculation unit corresponding to the above-mentioned predetermined time point. Then, when the comparison result is equal to or more than a predetermined value, the position of the mobile body based on the autonomous data is selected, and when the comparison result is less than the predetermined value, the position of the mobile body based on the GPS type data is selected.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a GPS navigation device according to one embodiment of the present invention. Then, this block diagram shows the function of calculating the moving position of the moving body by the GPS positioning and the self-contained positioning which are the background art of the present invention. In FIG. 1, a GPS antenna (11) for receiving radio waves from a plurality of artificial satellites constituting the GPS is a GPS receiver for performing necessary processing such as amplification and demodulation of the received radio waves. Connected to the section (12). The GPS receiving section (12) is connected to a GPS positioning calculating section (13) for obtaining the two-dimensional position and the three-dimensional position of the moving body. On the other hand, a direction sensor (14A) for detecting the moving direction of the moving body and a distance sensor (14B) for detecting the moving distance of the moving body are provided, and these are provided in the self-supporting position detecting means (14). It is connected so that the current position of the moving body can be detected. The GPS positioning calculation section (13) and the self-sustaining position detection means (14) are connected to the position determination means (15), and the GPS positioning calculation section (13) is calibrated via the calibration means (19). It is connected to the self-supporting position detecting means (14).
Here, the calibration means (19) uses the GPS positioning calculation section (13) to calculate the current position data of the mobile body obtained by the self-standing position detection means (14) when GPS positioning is possible. By calibrating with the obtained current position data,
This is for making a necessary correction. Further, the position determining means (15) is connected to an appropriate display device (18) via a drawing function section (17). This position determining means (15)
Has a kind of switching selection function, and GP
When S positioning is possible, the current position data obtained by the GPS positioning calculation unit (13) is selected and supplied to the drawing function unit (17) additionally provided with the map data storage device (16).
When the GPS positioning is impossible, the current position data obtained by the self-supporting position detecting means (14) is supplied to the drawing function section (17). Then, in the drawing function unit (17), the map data corresponding to the current position of the moving body is taken out from the map data storage device (16), and the state of being superimposed on the current position of the moving body is drawn. Is displayed on the display device (18).

FIG. 2 is a functional block diagram calibrated by focusing on the electrical processing function of each means and function in FIG. In FIG. 2, the same reference numerals as those in FIG. 1 denote the same or corresponding parts. What is included in the microcomputer (20) is a CPU (21) for performing required arithmetic processing on various input data, and various CPUs for causing the CPU (21) to perform required arithmetic processing. RO for storing programs
M (22), for temporarily storing various data to be arithmetically processed and data as the result of intermediate arithmetic processing
RAM (23) and a plurality of input / output circuits (13A), (14
AA), (14BB), (16A), (17A) and (24A). Then, for example, the GPS positioning calculation section (13) is connected to the CPU (21) via the input / output circuit (13A). Similarly, the direction sensor (14A), the distance sensor (14B), the map data storage device (16), and the drawing function unit (17) respectively correspond to the input / output circuits (14AA), (14BB), (16BB),
It is connected to the CPU (21) via (A) and (17A). The operation key (24) attached to the microcomputer (20) is connected to the CPU via the corresponding input / output circuit (24A).
It is connected to (21).

FIG. 3 is a flow chart for illustrating the operation by a predetermined program stored in the ROM (22) in the microcomputer (20) in FIG. Now, when a proper function command is issued by selecting and pressing a predetermined function key of the operation keys (24) (S1), the GPS positioning calculation unit (1
In 3) the predetermined GPS positioning processing is started,
An operation of reading the moving distance of the moving body by the distance sensor (14B) is performed (S2). Then, the moving distance data L thus read is stored in a predetermined address position in the RAM (23). In the GPS positioning calculation unit (13), the GPS positioning process is repeated at a certain time interval after the activation described above, and the resulting GPS positioning data is stored in the microcomputer (20).
Is added to Here, what is included in the so-called positioning data is the moving distance of the moving body obtained from the distance sensor (14B) and status information for instructing whether or not GPS positioning is possible. This status information is information indicating that the position of the moving body is obtained by receiving radio waves from three or more artificial satellites and GPS positioning is possible. If the positioning is possible, for example, the status information is set to "0", and if the positioning is not possible, the status information is set to "1". In the next step (S3), it is determined whether the status information obtained as described above is valid. That is, it is determined that GPS positioning is possible (YE
S) Sometimes, the process moves to the next step (S4). On the other hand, it was not determined that GPS positioning was possible (N
In some cases, it will wait until a YES determination is made. In this step (S4), the direction sensor (14
A) and the distance sensor (14B) detect the current independent position of the moving body, and the detection result is transferred to the microcomputer (20) and stored in a specified address position in the RAM (23). It Assuming that the mobile body is moving in an approximately planar area, the X-axis represents the east-west direction of the area, and the Y-axis represents the north-south direction orthogonal to the east-west direction. The point can be represented by a point on the Cartesian coordinate system by the X axis and the Y axis. Then, assuming that the independent current position data of the moving body defined in this way is represented as a value (Xs, Ys), this value (Xs, Ys) is stored in the RAM (23). It will be. Then, in this step (S4), the current position data (represented by the corresponding latitude and longitude) by GPS positioning from the GPS positioning calculation unit (13) is converted into the corresponding current position data on the orthogonal coordinate system. Converting to (Xo, Yo), the value (Xs, Ys) of the current position data of the mobile unit's self-supporting type stored by the various sensors stored in the RAM (23) is measured by GPS.
Initialize to the value (Xo, Yo) of the current position data of the moving body by positioning. Next, in step (S5), RAM (2
3) The value (X, Y) of the current position data of the moving body stored in
o, Yo). In the next step (S6), the microcomputer (20) reads the map data of the area including the current position of the moving body from the map data storage device (16). Then, the drawing function section (17) draws a map of the area based on the map data. The map drawn in this way is displayed by the display device (18). In the next step (S7), the drawing function section (17) causes the cursor to be displayed on the map displayed on the display device (18) at a position corresponding to the current position of the moving body. In the next step (S8), it waits for the GPS positioning data from the GPS positioning calculator (13) to arrive. Then, when the GPS positioning data from the GPS positioning calculation unit (13) arrives, the process proceeds to the next step (S9) and the contents of the status information put together, that is, "0" indicating that GPS positioning is possible. By determining information or “1” information indicating that GPS positioning is not possible,
A determination is made as to whether positioning is possible. If the result of this determination is YES, the next step (S
Moving to 10), the current position of the moving body is calibrated based on various data from various sensors. That is, in this step (S10), the GPS positioning calculation unit (13) performs GPS positioning based on the values (Xs, Ys) of the current position data of the moving body detected based on various data from various sensors. A value (Xgps, Ygp) on the Cartesian coordinate system formed about the area where the moving body exists as the current position data of the moving body.
s) is calibrated. Then, in the next step (S11), the current position (X, Y) of the moving body is determined by GPS.
It is assumed to correspond to the current position (Xgps, Ygps) by positioning. Then, in the next step (S15), it is determined whether or not the map to be displayed needs to be changed in relation to the current position of the moving body. On the other hand, when the result of the determination in step (S9) is NO, step (S1
The process moves to 2) and the direction sensor (14A) and the distance sensor (14B) are read. That is, the direction sensor (1
4A) reads the moving direction θ of the moving body. Further, the moving distance Lo of the moving body is read by the distance sensor (14B), the moving distance ΔL of the moving body within a certain fixed time is obtained by (ΔL = Lo−L), and then the Lo is the reference movement at that time point. The distance L is stored in the RAM (23). In the next step (S13), an addition operation is performed on the independent current position (Xs, Ys) of the moving body detected by the various sensors, using the X-axis direction component and the Y-axis direction component of ΔL. That is, the self-supporting current position (Xs, Ys) of the moving body detected by the various sensors is updated as Xs + ΔL · Cosθ → (new) Xs Ys + ΔL · SinΔ → (new) Ys.
In the next step (S14), the self-supporting current position (Xs, Ys) of the moving body detected by the various sensors corresponds to the current position (X, Y) of the moving body. Then, the process proceeds to the next step (S15). When the result of the determination in this step (S15) is YES, the process moves to step (S16), a new map is displayed, and then the current position of the moving body is displayed (S17). On the other hand, when the result of the determination is NO, the process goes straight to step (S17), and the current position of the moving body is displayed on the map which is not changed.

FIG. 4 is a block diagram showing a GPS navigation device that selects the position of a moving body based on the GPS-type speed-dependent data and the self-standing speed-dependent data, which is a feature of the present invention. In FIG. 4, (41) is a GPS antenna for receiving satellite radio waves, and the output side of this GPS antenna (41) is G
It is connected to the PS receiver (42). (43) is an azimuth sensor, and (44) is a distance sensor, which are connected to the position detecting device (45) together with the output side of the GPS receiving section (42). The output side of the position detecting device (45) is connected to the data processing device (46), and the map data storage device (47) and the display device (48) are connected to the data processing device (46). Has been done. Further, the data processing device (46) includes a comparator (46A) having a function described later, and the GPS data storage device (46B) and the self-standing data storage device (46C) are the data processing device (46A). )It is connected to the.

FIG. 5 is a flow chart for explaining the method of the position selecting operation, and FIG. 6 is an operation illustration of the other embodiment. In addition, in FIG.
The same reference numerals as those in FIG. 9 indicate the same or corresponding ones.

Next, the position selecting operation shown in FIG. 4 will be described with appropriate reference to FIGS. 5 and 6. An operator of a moving body such as a vehicle activates the GPS navigation device according to the other embodiment by pressing a start key on a keyboard (not shown), for example. Referring also to FIG. 5, assuming that the current position of the moving body is generally known, the required map data corresponding to this current position is retrieved from the map data storage device (47) (S50 ), The display device (4 via the data processing device (46)
Displayed in 8) (S51). And the radio waves from the satellite
It is received by the GPS antenna (41) as satellite data (S
52), position detection device (45) and data processing device (46)
Then, appropriate processing is performed to calculate its own current position (S53), and its moving speed and acceleration are calculated (S54). Next, the moving speed and acceleration of the self-supporting functional unit are calculated based on the required data fetched from the direction sensor (43) and the distance sensor (44) (S55). The data in step (S54) is temporarily stored in the GPS data storage device (46B), and the data in step (S55) is temporarily stored in the self-standing data storage device (46C). Then, the difference between the GPS data at a certain time point and the self-contained data obtained at the same time as this point or immediately before that point is determined, and it is judged whether the result is within the range of the predetermined limit value. Is performed by the comparator (46A) (S56). And the result of the judgment is YES
If it is, the current position is displayed based on the GPS data which is satellite data (S57), and the step (S
Return to 51). On the other hand, when the result of the determination is NO, the current position of the player is displayed based on so-called self-supporting data (S58), and the process returns to step (S51). Referring also to FIG. 6, the time zone t ₁ −
At t ₂ , t ₃ −t ₄ and t ₅ −t ₆ , the result of the judgment in step (S56) of FIG. 5 was NO, so the data from the GPS function unit is ignored and the autonomous function The data from the department is selected and the current position of the user is displayed. Therefore, the jump phenomenon in the conventional example is surely prevented from occurring, and the serious accident as a result of erroneous recognition of the current position is also prevented from occurring.

[Effects of the Invention] As described above, the GPS navigation device according to the present invention uses the position data obtained from the self-sustaining position detection means and the GP.
The self-sustaining speed-dependent data consisting of the speed or acceleration of the moving body at a predetermined time, which is the output of the self-sustaining position detecting means, is used to determine which of the position data obtained from the S-type positioning calculator is to be selected. And the velocity or acceleration of the moving body which is the output of the GPS type positioning calculation unit corresponding to the above predetermined time point.
Compare with GPS type speed-dependent data, if the comparison result is more than a predetermined value, select the position of the moving body by self-supporting data,
If the value is less than the specified value, the position of the moving object is selected by GPS type data.Therefore, the abnormal jumping in which the position data suddenly changes due to multipath in which the radio waves propagating from the artificial satellite are reflected by other objects or abnormalities in the ionosphere, etc. Since it is possible to judge with high sensitivity and switch to the data side of the accurate position, it is possible to detect the current position of the moving object with high accuracy and prevent the occurrence of an accident as a result of misrecognition of the current position due to a jumping phenomenon. There is an effect.

[Brief description of drawings]

FIG. 1 is a block diagram showing a GPS navigation device according to an embodiment of the present invention, and FIG. 2 is a functional block diagram constructed by focusing on its electric processing function in the above embodiment. FIG. 3 is a flow chart for explaining the operation of the above embodiment, and FIG. 4 shows a GPS navigation device for selecting the position of a moving body based on the GPS type speed dependent data and the independent type speed dependent data of the present invention. FIG. 5 is a block diagram showing the position selection operation, FIG. 5 is a flow chart of the position selection operation, FIG. 6 is an illustration of the operation of the position selection operation, and FIG.
Fig. 8 is a block diagram showing a GPS navigation device.
FIG. 9 is a block diagram showing a PS navigation device, and FIG. 9 is a diagram showing the operation of another conventional example. (11) is a GPS antenna, (12) is a GPS receiver, and (13) is
GPS positioning calculation unit, (14A) azimuth sensor, (14B) distance sensor, (14) self-supporting position detecting means, (15) position determining means, (16) map data storage device, (17) Drawing function unit, (18) display device, (19) calibration means, (20) microcomputer, (21) CPU, (22) ROM,
(23) is RAM, (24) is operation key. In the drawings, the same reference numerals indicate the same or corresponding parts.

Front Page Continuation (72) Inventor Koji Yamada 5-1-1 Shimorenjaku, Mitaka City, Tokyo Japan Radio Co., Ltd. (72) Inventor Makoto Mikuri 8-1-1 Tsukaguchihonmachi, Amagasaki City, Hyogo Sanryo Electric Co., Ltd. Company Applied Equipment Laboratory (72) Inventor Seiichiro Hirata 2-33 Miwa, Mita City, Hyogo Prefecture Mitsubishi Electric Corporation Mita Works (72) Inventor Kazuhiro Yokouchi 2-33 Miwa, Mita City, Hyogo Prefecture Mitsubishi Electric Machinery Co., Ltd. Mita Works (72) Inventor Tatsumi Kageyama 2-33 Miwa, Mita City, Hyogo Prefecture Mitsubishi Electric Co., Ltd. Mita Works (56) Reference JP 62-298717 (JP, A)

Claims (1)

[Claims] 1. A map data storage device for storing map data, GPS receiving means for receiving radio waves from a plurality of artificial satellites belonging to GPS, and at least velocity or acceleration of a moving body based on an output signal from the GPS receiving means. A GPS positioning calculation unit that obtains GPS type data representing one and a position, a self-sustaining detecting unit that detects a traveling direction and a traveling distance of the moving body, and a self-sustaining unit based on the traveling distance that is an output of the self-sustaining detecting unit. Self-sustaining position detecting means for obtaining self-sustaining data representing at least one of the velocity or acceleration of the moving body as data and a position, GPS type speed dependent data having at least one of the GPS type data, the self-sustaining Independent velocity dependent data having at least one of velocity or acceleration of the moving body of the type data, the GPS type velocity dependent data at a certain time and If the comparison result is compared with the self-sustaining speed-dependent data at a time point corresponding to the time point and the comparison result is a predetermined value or more, the position of the moving body of the self-standing type data is selected, and the comparison result is a predetermined value or less. In this case, there is provided a selection means for selecting the position of the mobile body in the GPS type data, and a display means for displaying the position of the mobile body in the map data in an overlapping manner based on the output from the selection means. GPS navigation device.