WO2006103893A1

WO2006103893A1 - Current position calculation device, current position calculation method, current position calculation program, and computer-readable recording medium

Info

Publication number: WO2006103893A1
Application number: PCT/JP2006/304579
Authority: WO
Inventors: Kazuaki Tanaka; Toshiki Fujiwara
Original assignee: Pioneer Corporation
Priority date: 2005-03-25
Filing date: 2006-03-09
Publication date: 2006-10-05
Also published as: JP4612675B2; JPWO2006103893A1

Abstract

In a current position calculation device, an acquisition unit (101) acquires signal information as information on a vehicle speed sensor from an in-vehicle information communication network. Next, a judgment unit (102) judges whether signal information has been acquired at a predetermined moment. Next, if it is judged that the signal information could not be acquired, an interpolation unit (103) interpolates the signal information to be acquired at the moment by predetermined signal information. When the signal is interpolated, a correction unit (104) acquires a correction value based on the interpolated signal information for signal information to be acquired at the moment next to the predetermined moment. By using the acquired correction value, it is possible to obtain and display an appropriate current position.

Description

Specification

Current position calculation device, current position calculation method, current position calculation program, and computer-readable recording medium

Technical field

The present invention relates to a current position calculation device, a current position calculation method, a current position calculation program, and a computer-readable recording medium that process signal information related to speeds that are continuously input. However, the use of the present invention is not limited to the above-described current position calculation device, current position calculation method, current position calculation program, and computer-readable recording medium.

Background art

[0002] In some recent vehicle models, the number of VSS signals (Vehicle Speed Sensors) detected by an ABS sensor or the like is broadcast as data (VSS signal information) on the in-vehicle LAN. For car navigation systems, etc., the travel distance and vehicle speed are calculated using this VSS signal.

Disclosure of the invention

Problems to be solved by the invention

[0003] In this case, since the acquisition of the VSS signal information is performed via communication, the VSS signal information may be delayed or lost depending on the load condition of the communication line. As an example, in a system that wakes up a task at a fixed period and calculates the travel distance and vehicle speed, a delay or loss of VSS signal information will result in an error in the calculated value. It is done.

[0004] The VSS signal information is an integrated value. On the other hand, even if the information is interpolated when the VSS signal information is delayed or missing, there is no VSS signal information at the previous timing when the VSS signal information power obtained at the next time is also obtained. Therefore, the problem that the number of VSS signals including an error is obtained is an example. In addition, there is a case where there is an error in the VSS signal information to be interpolated. For example, the problem of obtaining the VSS signal information including the error is given as an example. Means for solving the problem

[0005] The present position calculation device according to the invention of claim 1 is characterized in that an information communication network power in a vehicle acquires signal information that is information of a vehicle speed sensor, and at a predetermined time, the acquisition means Determining means for determining whether or not the signal information has been acquired; and when the determining means determines that the signal information has not been acquired, the signal information to be acquired by the acquiring means at the predetermined time point is determined as a predetermined signal. Interpolating means for interpolating with information, and when signal information is interpolated by the interpolating means, signal information acquired at a time point subsequent to the predetermined time point is used as signal information interpolated by the interpolating means. Correction means for obtaining a correction value based on the correction means.

[0006] In addition, the present position calculation method according to the invention of claim 5 includes an acquisition step of acquiring signal information that is also information on the vehicle speed sensor and information communication network power in the vehicle, and at a predetermined time point, A determination step for determining whether or not the signal information has been acquired by the acquisition step; and a signal to be acquired by the acquisition step at the predetermined time when it is determined that the signal information has not been acquired by the determination step An interpolation process for interpolating information with predetermined signal information, and when the signal information is interpolated by the interpolation process, the signal information acquired at a time point subsequent to the predetermined time point is determined by the interpolation process. And a correction step of obtaining a correction value based on the signal information interpolated by the above.

[0007] Further, a current position calculation program according to claim 6 causes a computer to execute the current position calculation method according to claim 5.

[0008] A computer-readable recording medium according to the invention of claim 7 is characterized in that the current position calculation program according to claim 6 is recorded.

Brief Description of Drawings

FIG. 1 is a block diagram showing a functional configuration of a current position calculation apparatus according to an embodiment of the present invention.

[FIG. 2] FIG. 2 is a flow chart showing processing of a current position calculation method that works on the embodiment of the present invention.

[FIG. 3] FIG. 3 is a block diagram showing a hardware configuration of a current position calculation apparatus that is useful in an embodiment of the present invention. [FIG. 4] FIG. 4 is a flowchart 1 to explain the processing of the present position calculation method which is effective in the embodiment of the present invention.

1—

FIG. 5 is an explanatory diagram for explaining a case where VSS signal information is acquired normally. [6] FIG. 6 is an explanatory diagram for explaining a case where a loss occurs in the acquisition of the VSS signal information. [7] FIG. 7 is an explanatory diagram for explaining a case where a delay occurs in the acquisition of the VSS signal information. Explanation of symbols

Acquisition department

102 Judgment part

103 Interpolator

104 Correction section

105 Position calculator

106 Display

301 LAN in the car

302 In-vehicle LAN controller

303 ABS sensor

304 ECU

305 Angular velocity sensor

306 Tilt sensor

307 GPS receiver

310 Navigation control unit

311 Operation unit

312 Display

313 point search part

314 Route search unit

315 Route guide

BEST MODE FOR CARRYING OUT THE INVENTION

With reference to the accompanying drawings, preferred embodiments of a current position calculation device, a current position calculation method, a current position calculation program, and a computer-readable recording medium according to the present invention will be described below. A suitable embodiment will be described in detail.

FIG. 1 is a block diagram showing a functional configuration of a current position calculation device according to an embodiment of the present invention. The current position calculation device of this embodiment includes an acquisition unit 101, a determination unit 102, an interpolation unit 103, a correction unit 104, a position calculation unit 105, and a display unit 106.

[0013] Acquisition unit 101 acquires signal information, which is information on a vehicle speed sensor, from an information communication network in the vehicle. The signal information can be given as an integrated value, for example. In this case, for example, the signal information can be a value obtained by adding all the input values (for example, the number of VSS signals) of the running start force. Or it can be set as the input value per unit time.

[0014] The determination unit 102 determines whether or not the signal information has been acquired by the acquisition unit 101 at a predetermined time point. For example, when signal information is input via the in-vehicle LAN, the signal information may not be acquired depending on the communication status. In this case, it is determined that the signal information could not be acquired.

Interpolation section 103 interpolates signal information to be acquired by acquisition section 101 at a predetermined time point with predetermined signal information when determination section 102 determines that the signal information has not been acquired. . By interpolating signal information, loss of signal information can be prevented. Further, the interpolation unit 103 can also supplement the signal to be acquired by the acquisition unit 101 at this predetermined time point using the signal information acquired before the predetermined time point. Since the previously used signal information is used, the processing load for obtaining the interpolation value can be minimized.

[0016] When the signal is interpolated by the interpolating unit 103, the correcting unit 104 calculates a correction value based on the signal information interpolated by the interpolating unit 103 with respect to signal information acquired at a time point subsequent to a predetermined time point. Ask.

[0017] Specifically, when it is determined that the signal information cannot be acquired at the time point N, the correcting unit 104 obtains the value indicated by the signal information at the time point N + 1 and the signal information at the time point N−1. The number of signals between time N-1 and time N + 1 is obtained by taking the difference between the values indicated, and the value indicated by the signal information at time N interpolated by the interpolation means and the value indicated by the signal information at time N-1 The number of signals at time N is obtained by taking the difference of By subtracting the number of signals at the time point N from the time point N−1 to the time point N + 1, the value including the correction value for the signal number at the time point N + 1 and the signal number at the time point N is obtained.

[0018] The correction value can be a value obtained by correcting the signal information acquired at the next time point (for example, time point N + 1). Alternatively, a value indicating the speed at the next time point can be obtained from the signal information acquired at the next time point, and the value indicating the speed can be corrected.

[0019] The position calculation unit 105 obtains the moving distance of the vehicle based on the signal information, and obtains the current position of the vehicle from the moving distance. The display unit 106 displays the current position obtained by the position calculation unit 105.

FIG. 2 is a flowchart showing the processing of the current position calculation method that works on the embodiment of the present invention. First, signal information is acquired (step S201). This signal information is information of the vehicle speed sensor from which the information communication network power in the vehicle is also acquired.

[0021] Next, it is determined whether or not signal information has been acquired at a predetermined time (step S202). If it is determined that the signal information could not be acquired (step S202: No), the signal information to be acquired at this predetermined time is interpolated with the predetermined signal information (step S203), and the process goes to step S206. move on.

If it is determined that the signal information has been acquired (step S202: Yes), it is determined whether or not the force has been subjected to the previous interpolation processing (step S204). If the previous interpolation process has not been successful (step S204: No), the process proceeds to step S206. When the previous interpolation processing was performed (step S204: Yes), the signal information acquired at the next time (that is, this time) after this predetermined time (that is, the time when interpolation processing was performed) is changed to the interpolated signal information. Based on this, find the correction value (Step S205)

Next, the travel distance of the vehicle is obtained based on the signal information, and the current position of the vehicle is obtained from the travel distance (step S206). Then, the obtained current position is displayed (step S207).

[0024] According to the embodiment described above, when signal information cannot be acquired due to delay or omission, for example, data blanks are filled with predetermined signal information, so that it is possible to prevent the processing from being deteriorated. Even when the signal information cannot be acquired, it is processed. Can continue.

[0025] On the other hand, the signal information acquired next is input as a value including the input value that has not been acquired previously, and an error remains as it is. Therefore, by correcting the signal information acquired next, it is possible to correct the deviation caused by the temporarily buried signal information and perform processing based on an accurate input value. In other words, the occurrence of errors due to signal information processing loss can be reduced by interpolation Z correction processing.

Example

[0026] (Hardware configuration)

FIG. 3 is a block diagram showing an example of the hardware configuration of the current position calculation device that is useful in the embodiment of the present invention. The current position calculation device includes in-vehicle LAN 301, in-vehicle LAN control unit 302, ABS sensor 303, ECU 304, angular velocity sensor 305, tilt sensor 306, GPS ratio 307, navigation control unit 310, operation unit 311, display unit 312, A point search unit 313, a route search unit 314, and a route guidance unit 315 are included.

The in-vehicle LAN 301 is an example of a current position calculation device, and is controlled by the in-vehicle LAN control unit 302. The in-vehicle LAN 301 is connected to an ABS sensor 303, an ECU 304, and a navigation control unit 310. Data output from each functional unit connected to the in-vehicle LAN 301 is shared via the in-vehicle LAN 301, and a functional unit that requires data acquires the data through the in-vehicle LAN 301.

[0028] Further, the navigation control unit 310 is connected with an angular velocity sensor 305, an inclination sensor 306, a GPS receiver 307, an operation unit 311, a display unit 312, a point search unit 313, a route search unit 314, and a route guide unit 315. ing. The in-vehicle LAN control unit 302 and each of these functional units include, for example, a CPU (Central Processing Unit) that executes predetermined arithmetic processing, a ROM (Read Only Memory) that stores various control programs, and a RAM ( Random Access Memory) can be used.

[0029] In-vehicle LAN 301 is a communication network in the vehicle, and is a CAN (Controller Area

Network), LIN, FlexRay, MOST and other communication protocols. Information used in each part of the vehicle is broadcast via this in-vehicle LAN 301. The in-vehicle LAN control unit 302 controls the in-vehicle LAN 301 so that each functional unit connected to the in-vehicle LAN 301 can acquire the VSS signal information. The acquisition unit 101 is realized by the in-vehicle LAN 301 and the in-vehicle LAN control unit 302. Further, the determination unit 102, the interpolation unit 103, and the correction unit 104 are realized by the in-vehicle LAN control unit 302.

[0031] The ABS sensor 303 is a sensor that detects the wheel speed. For example, a sensor that electromagnetically detects the unevenness of a rotor that rotates in conjunction with a wheel and outputs a signal can be given. The signal output at this time is called a VSS signal. The VSS (Vehicle Speed Sensor) signal is a signal generated when the vehicle travels. The ABS sensor 303 calculates the number of times this VSS signal is detected, that is, the number of VSS signals, and outputs it to the in-vehicle LAN 301 as VSS signal information.

Note that this VSS signal information is an integrated value of the number of VSS signals, and is not the number of detected VSS signals per unit time but the total number of detected signals. Then, the travel distance and the vehicle speed are obtained based on the number of VSS signals obtained based on the VSS signal information.

[0033] The number of VSS signals per unit time is obtained as the number of rising edge detections per unit time. Alternatively, there are a method of obtaining the number of detections of the falling edge and a method of obtaining the number of detections of both the rising edge and the falling edge. When the speed changes, the number of pulses obtained in a given time is different. Each different value is given as the number of VSS signals.

[0034] Then, for example, the VSS signal information is output as an integrated value that is the total force when the vehicle starts to run. Therefore, even if the VSS signal information does not arrive once, the VSS signal information obtained at the next timing includes the number of VSS signals that have been delivered and the number of VSS signals in the next section. Since the VSS signal information is obtained as an integrated value, the number of VSS signals can be obtained by taking the difference.

An ECU (Electronic Control Unit) 304 is a computer unit that controls the engine based on information from various sensors sent from the engine. The ECU 304 mainly controls engine fuel adjustment and ignition timing. For example, the fuel injection amount and ignition timing are determined based on information such as the air intake amount and throttle opening. Calculate the information from the sensor that measures the intake air amount and the oxygen amount contained in the exhaust gas. An instruction to output an appropriate amount of fuel is output. These control information is input to the in-vehicle LAN 301 in the same manner as the VSS signal information.

[0036] The angular velocity sensor 305 detects the angular velocity at the time of rotation of the own vehicle, and outputs the angular velocity data and the relative bearing data of the own vehicle. The inclination sensor 306 detects the inclination angle of the road surface and outputs inclination angle data.

[0037] The GPS receiver 307 receives a radio wave from a GPS satellite and obtains the current position of the apparatus body. The GPS receiver 307 receives radio waves from a GPS satellite and obtains a geometric position with respect to the GPS satellite, and can be measured anywhere on the earth. As radio waves: 1. It is carried out using L1 radio waves with CZA (Coarse and Access) codes and navigation messages on 57542 GHz carrier waves. This detects the current vehicle position (latitude and longitude). Furthermore, information collected by various sensors such as a vehicle speed sensor and a gyro sensor may be taken into consideration.

[0038] The navigation control unit 310 controls the entire navigation device. Further, the moving distance is obtained from the obtained number of VSS signals, and the current position is obtained from the moving distance. Also, an arbitrary point is searched, and an optimum route to the point is calculated based on the obtained point information. Also, real-time route guidance information is generated based on this route and the vehicle location information. The position calculation unit 105 is realized by the navigation control unit 310.

[0039] The operation unit 311 includes an operation button, a remote control, a touch panel, and the like. The display unit 312 includes a liquid crystal display, an organic EL display, and the like. The display unit 106 is realized by the display unit 312.

The point search unit 313 searches for an arbitrary point based on the information input from the operation unit 311 and outputs it to the display unit 312. Further, the route search unit 314 calculates an optimum route to the point based on the point information obtained by the point search unit 313. Further, the route guidance unit 315 generates real-time route guidance information based on the information obtained by the route search unit 314 and the vehicle position information.

FIG. 4 is a flow chart for explaining the processing of the current position calculation method that works on the embodiment of the present invention. First, the ABS sensor 303 is activated (step S401). By starting the ABS sensor 303, VSS signal information is sequentially input to the in-vehicle LAN 301. Next, it is determined whether or not the VSS signal information can be acquired (step S402). In other words, it is determined whether or not VSS signal information has been acquired due to a communication loss.

If the VSS signal information can be acquired (step S402: No), the VSS signal information interpolation processing is executed (step S403), and the series of processing ends. That is, the VSS signal information is acquired as an estimated value in order to prevent the VSS signal information from being acquired. For example, by using the previously used value as the VSS signal, the processing can be continued even when the VSS signal information cannot be obtained.

[0044] If the VSS signal can be acquired (step S402: Yes), it is determined whether the previous interpolation processing has been performed (step S404). If the previous interpolation processing was performed (step S404: Yes), correction processing is executed for the VSS signal acquired this time (step S405), and the process proceeds to step S407.

[0045] The previous VSS signal information obtained as an estimated value by the interpolation process is not an accurate input value. In addition, since the VSS signal information acquired next is input as a value including the input value that was previously acquired, it was input as an estimated value when calculating the number of VSS signals to be acquired next. It is necessary to subtract the number of VSS signals. This correction process corrects the deviation caused by the estimation result and obtains the number of VSS signals reflecting the correct input value.

[0046] If the previous interpolation processing has not been performed (step S404: No), the number of VSS signals is calculated (step S406). If there is no missing VSS signal and no previous interpolation processing is performed, the moving distance can be obtained by multiplying the number of VSS signals by the distance coefficient. This distance coefficient is a coefficient indicating the moving distance with respect to the amount of change in the number of VSS signals. The vehicle speed can be obtained by dividing the distance traveled by time.

[0047] Next, VSS signal information is recorded (step S407), and a series of processing ends. When the next VSS signal is acquired, data loss may occur due to delay or omission, so it is necessary to prepare data for interpolation at that time. Therefore, by recording the obtained VSS signal information, it is possible to prepare the data to be interpolated for the next missing VSS signal information. FIG. 5 is an explanatory diagram for explaining a case where the VSS signal information is normally acquired. The VSS signal information is processed continuously every N seconds. This time interval of N seconds is very short, for example every second. The VSS signal information processing timing will be described as 0 seconds to N5 seconds. By sequentially receiving the VSS signal information, the VSS signal information is acquired.

[0049] First, VSS signal information is received in 0 seconds, and VSS signal information is received in N seconds after section A. Then, after section B, VSS signal information is received in N2 seconds. Similarly, VSS signal information is received in N3 seconds after section C, VSS signal information is received in N4 seconds via section D, and VSS signal information is received in N5 seconds after section E. The At each time point from N seconds to N5 seconds, the number of VSS signals in sections A to E is determined based on the received VSS signal information.

FIG. 6 is an explanatory diagram for explaining a case where a loss occurs in the acquisition of VSS signal information. As in the normal case described in Fig. 5, VSS signal information is normally received at 0 and N seconds. Here, it is assumed that a loss occurs in the reception of the signal from the ABS sensor 303. At this time, VSS signal information is not normally received in N2 seconds.

[0051] Since the ABS sensor 303 outputs the VSS signal information as an integrated value, in the conventional case, the vehicle moves as long as it moves in N2 seconds. Therefore, the signal that should be received in N2 seconds is interpolated using the VSS signal information received in N seconds! The interpolation value is not necessarily the same value as the VSS signal information that should be received in N2 seconds. However, by considering the situation that the vehicle is traveling by interpolation, it is more appropriate to treat it as traveling at the same speed as in N seconds rather than not moving. The process can be executed based on any value.

[0052] Next, when the VSS signal information is normally received in N3 seconds, the interpolation process is performed in N2 seconds, and if it is processed as it is using the received VSS signal information for N3 seconds, Deviation occurs when calculating the number of VSS signals in section B. Therefore, in N3 seconds, the number of VSS signals in section C is corrected based on the interpolated value in N2 seconds. By correcting, it is possible to prevent an error in N3 seconds from being generated by the interpolation value in N2 seconds. [0053] In N4 seconds, the VSS signal information is normally received. Since the VSS signal information is processed normally in the previous N3 seconds, the VSS signal information is processed as it is in the next N4 seconds. In N5 seconds, the VSS signal information is normally received, and the VSS signal information is processed as it is.

FIG. 7 is an explanatory diagram for explaining a case where a delay occurs in the acquisition of the VSS signal information. As in the normal case described in Fig. 5, VSS signal information is normally received at 0 and N seconds. Here, it is assumed that there is a delay in receiving a signal from the ABS sensor 303. At this time, as in the case of FIG. 6, VSS signal information is not normally received in N2 seconds.

[0055] Similar to the case of signal loss, in the conventional case, the vehicle is treated as not moving in N2 seconds. Therefore, the number of VSS signals obtained in N seconds is used to interpolate signals that should be received in N2 seconds. Interpolation makes it possible to execute processing based on a more appropriate value by treating it as traveling at the same speed as in N seconds rather than not moving.

Next, in N3 seconds, both VSS signal information that should be received in N2 seconds and VSS signal information that is received in N3 seconds are received. Similarly to the case of signal loss, the interpolation processing is performed in N2 seconds, and if processing is performed using the VSS signal information received in N3 seconds, a deviation occurs.

First, VSS signal information that should be received after N2 seconds is canceled, and VSS signal information corresponding to N3 seconds is received. Also, the number of VSS signals obtained at N3 seconds is corrected based on the interpolation value at N2 seconds. By correcting, it is possible to prevent an error in N3 seconds from being caused by the interpolation value in N2 seconds.

Next, correction processing and interpolation processing will be described. Errors caused by information delay or omission in the in-vehicle LAN301 are reduced by interpolation 'correction processing. On the other hand, the VSS signal information broadcast to the in-vehicle lan 301 is an integrated value. Then, based on the number of VSS signals, which is the integrated value, the travel distance and the vehicle speed are obtained at regular intervals.

However, when communication loss or delay occurs, an accurate calculated value cannot be obtained. On the other hand, interpolation processing is executed using the previous value. This reduces instantaneous errors. On the other hand, since the vehicle is moving, calculate the correct value to interpolate with the previous value Since this is not possible, an integration error occurs.

[0060] When the VSS signal information is acquired from the in-vehicle LAN 301, as shown in FIG. 5, when the VSS signal information can be acquired at regular intervals in the normal case, the VSS signal information is displayed as shown in FIG. When missing, as shown in Fig. 7, there are three possible patterns of delay, although VSS signal information is not missing.

[0061] As described with reference to FIG. 5, since the VSS signal information is acquired at regular intervals in the normal case, the movement distance and the vehicle speed can be normally calculated without the need for interpolation processing and correction processing. it can. On the other hand, as described with reference to FIGS. 6 and 7, when the VSS signal is lost or delayed, the travel distance between B and the vehicle speed cannot be calculated.

Here, at the time point of N2 seconds, B is interpolated with the value calculated between A. This can reduce instantaneous errors. Although the previous value is used as it is as an interpolated value, the previous value can be corrected using a value estimated in consideration of acceleration or the like. However, since this is an interpolation process, a slight error occurs between the actual travel distance between B and the vehicle speed. Here, the calculated value between the interpolation processes is the interpolation value X, and the interpolation value is stored in order to remove this error.

[0063] Then, when the VSS signal information is acquired after the next time, the difference from the VSS signal information at the previous reception is calculated. Let the difference Y be the value obtained here. In other words, when the VSS signal is received at the time point of N3 seconds, the number of VSS signals including the section that has not been received is calculated from the difference between the acquired VSS signal information and the previously acquired VSS signal. Specifically, the number of VSS signals between C is obtained from the total number of VSS signals between B and C.

[0064] By subtracting the interpolation value X from the difference Y, a calculation result obtained by subtracting the integration error can be obtained. In other words, by subtracting the retained compensation value from the total number of VSS signals in these two sections, it is possible to calculate the travel distance that offsets the error. Specifically, the number of VSS signals between C can be calculated by subtracting the interpolation value, which is the estimated number of VSS signals used in the interpolation process, from the total number of VSS signals between B'C. As a result, the integration error can be eliminated, and a total correct calculation value can be obtained.

A method for calculating the number of VSS signals (number of VSS signals per unit time) will be described. First, the VSS signal information broadcast on the vehicle LAN 301 is acquired. Next, calculate the number of VSS signals. The The number of VSS signals can be obtained by the following equation: “VSS signal number = currently acquired VSS signal information—previously acquired signal information” t.

[0066] The travel distance / vehicle speed can be calculated based on the number of VSS signals. First, the travel distance is obtained by multiplying the distance coefficient by the number of VSS signals. The distance coefficient is the moving distance per VSS signal. The vehicle speed can be obtained by dividing the travel distance by time.

[0067] According to the embodiment described above, the occurrence of an error when information is delayed or lost in the in-vehicle LAN can be reduced by the interpolation Z correction process. For example, by acquiring VSS signal information using the previously used value as an estimated value, it is possible to prevent a situation where VSS signal information cannot be acquired. The processing can be continued even at a powerful timing when the VSS signal information cannot be acquired.

On the other hand, since the VSS signal information acquired next is input as a value including the input value that was not acquired last time, an incorrect number of VSS signals is obtained as it is. Therefore, by correcting the VSS signal information acquired next, it is possible to correct the deviation due to the estimation result and acquire the number of VSS signals reflecting the accurate input value.

Note that the current position calculation method described in the present embodiment can be realized by executing a program prepared in advance on a computer such as a personal computer or a workstation. This program is recorded on a computer-readable recording medium such as a hard disk, a flexible disk, a CD-ROM, an MO, and a DVD, and is executed by reading the recording medium force by the computer. The program may be a transmission medium that can be distributed through a network such as the Internet.

Claims

The scope of the claims

[1] Information communication network power in the vehicle Acquisition means for acquiring signal information that is information of the vehicle speed sensor;

A determination means for determining whether or not the signal information has been acquired by the acquisition means at a predetermined time;

An interpolation means for interpolating the signal information to be acquired by the acquisition means at the predetermined time point with predetermined signal information when the determination means determines that the signal information could not be acquired;

When signal information is interpolated by the interpolating means, correction means for obtaining a correction value based on the signal information interpolated by the interpolating means for signal information acquired at a time point subsequent to the predetermined time point When,

A current position calculation device comprising:

[2] The interpolating means interpolates signal information to be acquired by the acquiring means at the predetermined time point using signal information acquired at a time point before the predetermined time point. 1. The current position calculation device according to 1.

[3] The signal information is given as an integrated value,

When it is determined at time N that the correction means has been unable to acquire signal information,

By calculating the difference between the value indicated by the signal information at the time N + 1 and the value indicated by the signal information at the time N−1, the number of signals between the time N−1 and the time N + 1 is obtained and interpolated by the interpolation means. The number of signals at time N is obtained by taking the difference between the value indicated by the signal information at time N and the value indicated by the signal information at time N−1, and the number of signals between time N−1 and time N + 1 is determined. 2. The current position calculating apparatus according to claim 1, wherein a value including a correction value for the number of signals at time N + 1 and the number of signals at time N is obtained by subtracting the number of N signals.

[4] A position calculating means for determining a moving distance of the vehicle based on the signal information, and determining a current position of the vehicle from the moving distance;

Display means for displaying the current position obtained by the position calculation means; The present position calculation apparatus according to any one of claims 1 to 3.

[5] Information communication network power in the vehicle An acquisition step of acquiring signal information that is information of the vehicle speed sensor;

At a predetermined point in time, a determination step for determining whether or not the signal information has been acquired by the acquisition step;

An interpolation step of interpolating signal information to be acquired by the acquisition step at the predetermined time point with predetermined signal information when it is determined that the signal information could not be acquired by the determination step;

When the signal information is interpolated by the interpolation step, the correction value is obtained based on the signal information acquired at the next time after the predetermined time point and based on the signal information interpolated by the interpolation step. A correction process for obtaining

The present position calculation method characterized by including.

[6] A current position calculation program causing a computer to execute the current position calculation method according to claim 5.

[7] A computer-readable recording medium on which the current position calculation program according to claim 6 is recorded.