JP2004220262A - Position information report device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a position information report device capable of efficiently performing communications with the outside. <P>SOLUTION: When the present vehicle speed is under a reference vehicle speed after the lapse of a predetermined time (step S12), it is determined whether a position information report exclusion flag is in a set state or not (step S15), and when it is in the set state, the flag is changed to a reset state (step S16), and the latest position information is acquired and transmitted to an external center 4 (step 13). On the other hand, when the position information report exclusion flag is in the reset state, the flag is changed to the set state (step S17), a timer is reset (step S14) to transfer the processing to step S11. According to this, when the present vehicle speed is a low speed under the reference vehicle speed, transmission of the position information to the center 4 can be deferred once for effective reduction of a communication cost. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a position information notification device.
[0002]
[Prior art]
Conventionally, in a system where the center grasps the position of the vehicle and grasps the operation status of the vehicle and instructs the vehicle to operate, the transmission cycle of the position information transmitted from the vehicle to the center is changed according to the position of the vehicle There is a position information notification device that performs the operation (for example, see Patent Document 1). According to the position information notification device disclosed in Patent Literature 1, for example, when a vehicle is located near a stop, the position of the vehicle is transmitted to the center at predetermined time intervals, and the traveling section away from the stop If the vehicle is located in the center, the communication frequency is transmitted to the center at a lower frequency than a predetermined time interval. As a result, in a traveling section away from the stop and not important for operation management, the position of the vehicle is not frequently transmitted, so that communication traffic is reduced.
[0003]
In addition, when detecting the position of the vehicle, the position information notification device compares the current position with the position detected last time, and when the two are the same (or the difference is smaller than a preset value). If it is smaller), it is determined that the vehicle is in a stopped state, and the position of the vehicle is not transmitted. As a result, unnecessary vehicle positions are not transmitted to the center, thereby reducing communication costs.
[0004]
[Patent Document 1]
JP-A-2002-74591
[Problems to be solved by the invention]
However, the conventional position information notification device transmits the position of the vehicle to the center when the current position and the previously detected position are not the same (or when the difference between the two is larger than a preset value). . Therefore, for example, even when the vehicle runs at a low speed (when the change in the position of the vehicle is small), the position of the vehicle is transmitted to the center as long as the above condition is satisfied. Is not reduced.
[0006]
The present invention has been made in view of such a problem, and an object of the present invention is to provide a position information notification device that can efficiently communicate with the outside.
[0007]
[Means for Solving the Problems]
The position information notification device according to claim 1, wherein the position detecting means detects a position of the moving body, a communication means transmits information of the detected position of the moving body to the outside, and a speed detecting means detects a speed of the moving body. Means, and communication interval changing means for changing a time interval for transmitting position information by the communication means based on the speed detected by the speed detecting means, wherein the communication means has a transmission time changed by the communication interval changing means. It is characterized in that position information is transmitted according to intervals.
[0008]
As described above, the position information notification device of the present invention changes the time interval for transmitting the position of the moving body to the outside based on the speed of the moving body. Thereby, for example, when the speed of the moving body is high, the position of the moving body greatly fluctuates, so that the time interval for transmitting the position of the moving body is shortened, and when the speed of the moving body is low, Since the position fluctuation of the moving body is small, the time interval for transmitting the position of the moving body can be lengthened. As a result, communication with the outside can be performed efficiently.
[0009]
The speed detecting means for detecting the speed of the moving object may be a speed sensor for directly detecting the speed, or the speed detecting means for detecting the speed of the moving object based on the history of the detected position of the moving object and the time difference between the detected positions. The speed may be obtained indirectly.
[0010]
In the position information notifying apparatus according to the second aspect, the communication interval changing unit changes the transmission time interval so that the transmission time interval becomes longer as the detected speed is lower. Thus, unnecessary communication when the change in the position of the moving object is small can be suppressed. As a result, communication costs can be reduced.
[0011]
According to the position information notification device of the third aspect, the communication interval changing unit pre-stores time intervals set so as to correspond to each of the plurality of divided speed ranges, and includes a speed including a detected speed. The transmission time interval is changed using the time interval of the area. Thereby, for example, it is possible to set a time interval for transmitting position information corresponding to a plurality of speed ranges such as a low / middle / high speed range.
[0012]
In the position information notification device according to the fourth aspect, the communication interval changing unit has a basic time interval in advance as a time interval for transmitting the information on the position of the moving object to the outside, and the basic time interval is determined based on the speed. The transmission time interval is changed by thinning out the transmission timing for each time interval.
[0013]
As described above, even in the position information device that transmits the position information to the outside at predetermined time intervals, the transmission timing is thinned based on the speed of the moving object, and the transmission time interval is determined according to the speed of the moving object. Can be changed.
[0014]
6. The position information notification device according to claim 5, wherein the communication interval changing unit forgoes transmission of position information by the communication unit based on the speed detected by the speed detection unit at the transmission timing arriving at each basic time interval. It is characterized by comprising a determination means for determining whether or not it is. In this way, by determining whether to forgo transmission of position information at each basic time interval based on the speed of the moving body, transmission of position information according to the level of the speed of the moving body is postponed. be able to.
[0015]
In the position information notifying apparatus according to a sixth aspect, the determining means determines that transmission of the position information for a predetermined number of times is forgotten when the detected speed is less than the predetermined speed. This makes it possible to forego transmission of position information when the moving body moves at a low speed, for example, and reduce communication costs.
[0016]
According to the position information notification device of claim 7, the determination means sets a plurality of speed ranges to be used as a reference when determining whether to postpone transmission of the position information and sets the plurality of speed ranges in advance. The number of times of sending-off of information at a smaller position is set as the speed is higher.
[0017]
As described above, when the speed of the moving object is high, the number of times of sending off of the position information is set to be small, while when the speed of the moving object is low, the number of times of sending off of the position information is set to be large. Is done. This makes it possible to transmit the position of the moving object suitable for the speed of the moving object.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a position information notification device according to an embodiment of the present invention will be described with reference to the drawings. It is assumed that the position information notification device according to the present embodiment is mounted on a vehicle and applied as a device that notifies the position of the vehicle to the outside.
[0019]
FIG. 1 is a block diagram illustrating a schematic configuration of a position information notification device 1 and peripheral devices according to the present embodiment. As shown in the figure, the position information notification device 1 of the present embodiment includes a position information detection unit 11, a position information notification time calculation unit 12, and a vehicle speed detection unit 13. The position information notification device 1 is connected to the data communication unit 2 and communicates with the center 4 via the data communication unit 2. Further, the vehicle speed detector 13 is connected to the vehicle speed signal generator 3.
[0020]
The position information notification timing calculation unit 12 is configured as a normal computer, and includes a well-known CPU, ROM, RAM, I / O, and a bus line connecting these components. A program to be executed by the position information notification timing calculation unit 12 is written in the ROM, and a CPU or the like executes a predetermined calculation process according to the program.
[0021]
The data communication unit 2 employs, for example, a mobile phone and is connected to the center 4 via an external network. The data communication unit 2 transmits the vehicle position information transmitted from the position information notification device 1 to the center 4. Note that the data communication unit 2 is not limited to a mobile phone, and is not particularly limited as long as it has a function that can be connected to an external network, such as an automobile phone, a mobile PC (Personal Computer) or a PDA (Personal Digital Assistant) having a communication function. It is not done.
[0022]
The center 4 obtains the position information from each vehicle received from the data communication unit 2 via the external network, manages the operation of the vehicles, and provides the position information of the other vehicles to the vehicles forming the group. Or
[0023]
The position information detecting unit 11 detects an absolute position of the vehicle, and is configured by a GPS (Global Positioning System) GPS receiver that detects the position of the vehicle based on radio waves from a known satellite. The position information detection unit 11 transmits information on the detected absolute position of the vehicle to the position information notification time calculation unit 12.
[0024]
The position information detection unit 11 is not limited to the GPS receiver, and may be configured by a plurality of sensors such as a well-known geomagnetic sensor and a gyroscope. However, when a plurality of sensors are used, each of them has an error having a different property.
[0025]
The vehicle speed detector 13 detects a vehicle speed signal generated by the vehicle speed signal generator 3. The detected vehicle speed signal is transmitted to the position information notification timing calculation unit 12. In this embodiment, the vehicle speed signal detected by the vehicle speed detection unit 13 is adopted as the vehicle speed. However, the history of the position of the vehicle detected by the position information detection unit 11 and the time difference between the detected positions are different from each other. , The speed of the vehicle may be obtained indirectly.
[0026]
The position information notification timing calculation unit 12 receives the position information of the vehicle transmitted from the position information detection unit 11 and transmits the position information of the vehicle to the center 4 via the data communication unit 2 at predetermined time intervals. is there. The position information notification timing calculation unit 12 has a timer function (not shown), and it is determined by the timer function whether a predetermined time has elapsed since the last time the position information was transmitted to the center 4.
[0027]
In the present embodiment, the timing at which the position information is transmitted to the center 4 is changed based on the vehicle speed transmitted from the vehicle speed detection unit 13. Hereinafter, the position information notification processing relating to the characteristic portion of the present embodiment will be described with reference to the flowchart shown in FIG.
[0028]
In step S10 shown in FIG. 2, initialization is performed. In this initial setting, initialization processing of variables used in internal processing, activation processing of the timer function described above, and the like are performed. Further, detection of a vehicle speed signal by the vehicle speed detection unit 13 is started. When the activation process of the timer function ends, time counting by the timer function starts.
[0029]
In step S11, it is determined whether or not the numerical value (Tcnt) of the timer is equal to or greater than a preset threshold (Tcyc). Here, if Tcnt is equal to or greater than Tcyc, the process proceeds to step S12. If a negative determination is made, the timer function continues counting until Tcnt becomes equal to or greater than Tcyc.
[0030]
When Tcnt is equal to or greater than Tcyc, in step S12, the magnitude relationship between the vehicle speed (V) transmitted from the vehicle speed detection unit 13 and a preset reference vehicle speed (Vb) is compared. Here, if the current vehicle speed (V) is lower than the reference vehicle speed (Vb), the process proceeds to step S15.
[0031]
On the other hand, if the current vehicle speed (V) is equal to or higher than the reference vehicle speed (Vb) in step S12, the latest vehicle position information is acquired from the position information detecting unit 11 in step S13, and the latest position information is obtained. The data is transmitted to the center 4 via the data communication unit 2.
[0032]
In step S14, the numerical value (Tcnt) of the timer is reset, and the process proceeds to step S11. Then, the above-described processing is repeated. Thus, when the current vehicle speed (V) is equal to or higher than the reference vehicle speed (Vb), the position information of the vehicle is transmitted to the center 4 every time the threshold value (Tcyc) elapses.
[0033]
In step S15, it is determined whether or not the position information notification exclusion flag (f) is in the set state (1). Here, when the position information notification exclusion flag (f) is in the set state (1), the position information notification exclusion flag is reset (0) in step S16, and then the process proceeds to step S13. On the other hand, when the position information notification exclusion flag (f) is in the reset state (0), the state is set to (1) in step S17, and then the process proceeds to step S14.
[0034]
As described above, the position information notification device 1 according to the present embodiment does not report the position information to the center 4 once when the current vehicle speed is equal to or lower than the reference vehicle speed (Vb). Thus, for example, when the vehicle moves at a vehicle speed lower than the reference vehicle speed (Vb), the transmission of the position information to the center 4 is forgotten, so that unnecessary communication to the outside when the change in the position of the vehicle is small is prevented. Can be suppressed. As a result, communication costs can be reduced.
[0035]
(Modification 1)
In the present embodiment, when the vehicle moves at a vehicle speed lower than the reference vehicle speed (Vb), the transmission of the position information to the center 4 is delayed by one time, but the number of times of transmission may be increased. Hereinafter, the position information notification processing when the number of times of sending off is increased will be described with reference to the flowchart shown in FIG. Note that the description of the same steps as the processing in the present embodiment will be omitted.
[0036]
In step S10 shown in FIG. 3, the variable (k) is initialized in addition to the initialization processing described above. In step S12, if the current vehicle speed (V) is lower than the reference vehicle speed (Vb), the process proceeds to step S20, and in this step S20, whether the variable (k) is "2" or not. Is determined. If the variable (k) is "2", "0" is substituted for the variable (k) in step S21, and the process proceeds to step S13 described above.
[0037]
On the other hand, if the variable (k) is not “2” in step S20, “1” is added to the variable (k) in step S22, and the process proceeds to step S14 described above. Thereby, when the variable (k) becomes equal to "2" in step S20, that is, two times of position information until the variable (k) changes from "0" to "2" can be postponed. As a result, the cost of communication to the outside when the vehicle moves at low speed can be reduced.
[0038]
(Modification 2)
In the present embodiment, when the vehicle moves at a vehicle speed lower than the reference vehicle speed (Vb), the transmission of the position information to the center 4 is postponed for one time. However, a plurality of reference vehicle speeds are set and the vehicle speed is reduced. A corresponding number of times of sending off may be set. Hereinafter, position information notification processing performed based on a plurality of set reference vehicle speeds and the number of times of see-through set in accordance with the height of the vehicle speed will be described with reference to flowcharts shown in FIGS. 4 and 5. Note that the description of the same steps as the processing in the present embodiment will be omitted.
[0039]
In step S30 shown in FIG. 4, the magnitude relationship between the current vehicle speed (V) and the reference vehicle speed 1 (Vb1) is compared, and if the current vehicle speed (V) is lower than the reference vehicle speed 1 (Vb1), The process proceeds to step S31, and if the current vehicle speed (V) is equal to or higher than the reference vehicle speed 1 (Vb1), the above-described processes after step S13 are executed.
[0040]
In step S31, the magnitude relation between the current vehicle speed (V) and the reference vehicle speed 2 (Vb2) smaller than the reference vehicle speed 1 (Vb1) is compared, and the current vehicle speed (V) is compared with the reference vehicle speed 2 (Vb2). If it is also larger, the process proceeds to step S32, and in steps S32 to S34, a process of sending off the position information once is executed.
[0041]
On the other hand, if the current vehicle speed (V) is equal to or lower than the reference vehicle speed (Vb2) in step S31, the process proceeds to step S40, and in steps S40 to S42, transmission of the position information is delayed twice. Execute.
[0042]
As described above, by setting a plurality of reference speeds and setting the number of times of sending off of position information according to the height of the reference speed, for example, if the number of times of sending off is increased as the vehicle speed becomes lower, the moving When the speed of the body is high, the number of times of seeing is small because the change in position is large. On the other hand, when the speed of the moving body is low, the number of times of seeing is small because the change in position is small. This makes it possible to transmit position information at intervals suitable for the vehicle speed.
[0043]
(Modification 3)
In the present embodiment, each time the threshold value (Tcyc) elapses, the current vehicle speed (V) is compared with the reference vehicle speed (Vb) to determine whether or not the transmission of the position information to the center 4 is to be stopped. ) May be determined based on the size of the position information transmission, and the position information may be transmitted using the time obtained by multiplying the threshold (Tcyc) by the number of thinnings (n) as the communication interval time. . Hereinafter, the position information notification processing of changing the transmission interval by thinning out the transmission timing will be described with reference to the flowchart shown in FIG. Note that the description of the same steps as the processing in the present embodiment will be omitted.
[0044]
In step S50 shown in FIG. 6, it is determined whether or not the value of the timer (Tcnt) is equal to or longer than a communication interval time (T) described later. If Tcnt is equal to or greater than T, the process proceeds to step S51. If a negative determination is made, the timer function continues counting until Tcnt becomes equal to or greater than T.
[0045]
When Tcnt is equal to or greater than T, in step S51, the current vehicle speed (V) is obtained, and in step S51, the number of thinning outs (n) of the transmission timing corresponding to the current vehicle speed (V) is obtained. .
[0046]
Note that the number of thinnings (n) may be derived in advance from a map or the like indicating the relationship between the vehicle speed and the number of thinnings. Further, by making the map such that the number of thinnings (n) increases as the vehicle speed (V) decreases, transmission at a low speed can be reduced.
[0047]
In step S53, a value obtained by multiplying the threshold (Tcyc) by the number of thinnings (n) is set as the communication interval time (T). As a result, the position information is transmitted to the center 4 at every communication interval time (T) obtained by thinning out the transmission timing for the number of times of thinning with respect to the threshold (Tcyc).
[0048]
(Modification 4)
The position information notification time calculation unit 12 of the present embodiment transmits the position information of the vehicle to the center 4 via the data communication unit 2 at predetermined time intervals, and directly derives the data communication cycle from the speed of the vehicle. A map that can be used may be prepared in advance, a communication cycle corresponding to the speed of the vehicle may be obtained from the map, and the position information of the vehicle may be transmitted at the communication cycle.
[0049]
For example, as shown in FIG. 7A, a communication cycle corresponding to the speed of the vehicle may be obtained from a map in which the communication cycle becomes shorter as the speed of the vehicle increases, or as shown in FIG. 7B. As described above, the communication cycle according to the speed of the vehicle may be obtained from a map in which the communication cycle suddenly becomes shorter as the speed of the vehicle increases to some extent.
[0050]
Further, as shown in FIG. 7 (c), the map is divided into a plurality of speed ranges (V1 to V4), and a communication cycle corresponding to each of the plurality of divided speed ranges is derived from a map according to the speed of the vehicle. The determined communication cycle may be obtained. Each speed range may be equally divided, or may be set so that the division width becomes narrower as the speed changes from a low speed to a high speed.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an overall configuration according to an embodiment of the present invention.
FIG. 2 is a flowchart illustrating a position information notification process according to the embodiment of the present invention.
FIG. 3 is a flowchart illustrating a position information notification process according to a first modification of the embodiment of the present invention.
FIG. 4 is a flowchart illustrating a first half of a position information notification process according to a second modification of the embodiment of the present invention.
FIG. 5 is a flowchart illustrating a second half of a position information notification process according to a second modification of the embodiment of the present invention.
FIG. 6 is a flowchart showing a position information notification process according to a third modification of the embodiment of the present invention.
FIGS. 7A to 7C are diagrams of a map showing a relationship between a vehicle speed and a communication cycle according to a fourth modification of the embodiment of the present invention.
[Explanation of symbols]
1 location information notification device 2 data communication unit 3 vehicle speed signal generation unit 4 center

Claims (7)

Position detecting means for detecting the position of the moving body,
Communication means for transmitting information on the detected position of the moving object to the outside,
Speed detection means for detecting the speed of the moving body,
Communication interval changing means for changing a time interval for transmitting the position information by the communication means based on the speed detected by the speed detection means,
The position information notifying device, wherein the communication unit transmits the position information according to the transmission time interval changed by the communication interval changing unit. The position information notification device according to claim 1, wherein the communication interval changing unit changes the transmission time interval so that the transmission time interval becomes longer as the detected speed is lower. The communication interval changing means stores in advance a time interval set so as to correspond to each of the plurality of divided speed ranges, and uses the time interval of the speed range including the detected speed to transmit the transmission time interval. 3. The position information notification device according to claim 1, wherein the position information notification device changes the position information. The communication interval changing unit has a basic time interval in advance as a time interval for transmitting the information on the position of the moving object to the outside, and by thinning out the transmission timing for each basic time interval based on the speed. 2. The position information notification device according to claim 1, wherein the transmission time interval is changed. The communication interval changing unit determines, at the transmission timing arriving for each of the basic time intervals, whether to stop transmitting the position information by the communication unit based on the speed detected by the speed detection unit. 5. The position information notification device according to claim 4, further comprising means. 6. The position information notification device according to claim 5, wherein the determination unit determines that transmission of the position information for a predetermined number of times is forgotten when the detected speed is less than a predetermined speed. The determining means sets a plurality of speed ranges to be used as references when determining whether or not to send the position information, and for each of the plurality of set speed regions, the higher the speed, the smaller the number of the position information. 6. The position information notification device according to claim 5, wherein the number of times of sending off is set.

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