JP5811558B2 - Mobile terminal and travel route calculation program - Google Patents

Description

  This case relates to a mobile terminal and a travel route calculation program.

  In recent years, navigation systems combining GPS (Global Positioning System) and autonomous navigation have become widespread. Recently, mobile terminals such as mobile phones equipped with the system have also appeared.

  Patent Document 1 discloses an azimuth specifying device that measures a position in time series and specifies an azimuth of a moving direction on a map. In this azimuth specifying device, the position on the map is estimated based on positioning data (GPS, geomagnetic sensor, etc.) obtained by positioning, and the own position on the map is determined based on the estimated position and map information. The road is specified, and the road direction at the specified position is specified as the direction of the own movement direction.

JP 2009-150724 A

  In one aspect, an object of the present invention is to provide a mobile terminal and a travel route calculation program that can accurately calculate a travel route.

The mobile terminal described in the present specification includes an absolute position detection unit that detects an absolute position of the mobile terminal, an acceleration detection unit that detects an acceleration of the mobile terminal, and a case where the mobile terminal moves in a predetermined direction from a certain point. In addition, a line segment length calculation unit that calculates a length of a line segment connecting the point from the certain point to a point where the moving direction is changed from the predetermined direction based on the detected change in acceleration, and the movement Based on the absolute position detected by the absolute position detector while the terminal is moving in the predetermined direction, the predetermined direction is calculated, and from the calculated direction and the length of the line segment, A travel route calculation unit that calculates a travel route of the mobile terminal from the certain point as a starting point, while the mobile terminal is moving in the predetermined direction from the certain point, the absolute position detection unit Absolute position The when a plurality of detection, the movement route calculating unit, as the absolute position close to the point where the present, so that the influence of the error of the absolute position has on the calculation of the predetermined direction is reduced, which is detected The mobile terminal calculates the travel route by reflecting the absolute position farther from the certain point among the plurality of absolute locations in the direction of the travel route.

  The mobile terminal and the travel route calculation program described in this specification have an effect that the travel route can be calculated with high accuracy.

It is a figure which shows schematically the structure of the mobile terminal which concerns on one Embodiment. It is a hardware block diagram of a mobile terminal. It is a functional block diagram of the control part of FIG. It is a flowchart which shows the whole flow of the process performed with a mobile terminal. It is a figure which shows the subroutine of the link acquisition process of step S12. It is a figure which shows a link database. It is a figure which shows a GPS database. It is a figure which shows the subroutine of step S20 of FIG. FIG. 9A is a diagram for explaining the processing in step S72 in FIG. 8, and FIG. 9B is a diagram for explaining the processing in step S74 in FIG. It is a figure for demonstrating the reason for performing weighting. FIG. 11A is a diagram illustrating an example of a link angle calculated when a weighting coefficient is not used, and FIG. 11B is a diagram illustrating an example of a link angle calculated when a weighting coefficient is used. is there. It is a figure which shows the example of the condition where an effect is exhibited regarding the case where a link angle is calculated using a weighting coefficient.

  Hereinafter, an embodiment of a mobile terminal will be described in detail with reference to FIGS. FIG. 1 shows a mobile terminal 100 in a block diagram. In this embodiment, as the mobile terminal 100, for example, a portable terminal such as a mobile phone, a PHS (Personal Handy-phone System), a smartphone, or a PDA (Personal Digital Assistant) is adopted. The mobile terminal 100 is not limited to this, and a portable navigation system, a GPS logger, or the like can also be employed.

  As shown in FIG. 1, the mobile terminal 100 includes an absolute position detection unit 30, a geomagnetic information detection unit 40, an acceleration information detection unit 50, a display screen 60, an input interface 62, and a control unit 20. . The mobile terminal 100 may have various functions such as a call function, a communication function such as mail and the Internet, and a photographing function. However, in FIG. 1, a configuration for realizing these functions is not illustrated. doing.

  In this embodiment, the absolute position detection unit 30 is a GPS receiver, and receives information from a plurality of GPS satellites existing in the sky and obtains information on the absolute position (position indicated by latitude and longitude). It is.

  The geomagnetic information detector 40 is also called an orientation sensor, and is a geomagnetic sensor capable of detecting geomagnetism on a three-axis coordinate system, that is, a magnetic orientation sensor. In place of the geomagnetic sensor, a gyro sensor (angular velocity sensor) may be used. The acceleration information detection unit 50 is, for example, a sensor that detects acceleration in three axis directions.

  The display screen 60 displays various types of information under the instruction of the control unit 20. For example, the display screen 60 displays information on the route traveled by the user holding the mobile terminal 100. The input interface 62 includes a keyboard and a touch panel.

  FIG. 2 shows a hardware configuration of the control unit 20. As shown in FIG. 2, the control unit 20 includes a CPU (Central Processing Unit) 90, a ROM (Read Only Memory) 91, a RAM (Random Access Memory) 92, and a storage unit (here, HDD (Hard Disk Drive)). 93, an input / output unit 94, and the like, and each component of the control unit 20 is connected through a bus 95. In the control unit 20, the CPU 90 executes a program (movement path calculation program) stored in the RAM 92 or the HDD 93, thereby realizing the functions of the processing units shown in FIG. The HDD 94 stores data obtained in the control unit 20 and functions as the information storage unit 23 in FIG. The input / output unit 94 is an input / output port that communicates with the display screen 60 and the input interface 62.

  FIG. 3 is a functional block diagram showing functions relating to the movement route calculation realized by the CPU 90 of the control unit 20 of FIG. As illustrated in FIG. 3, the control unit 20 functions as a detection control unit 21, a link information generation unit 22 as an acquisition unit, an information storage unit 23, a movement route calculation unit 24, a display control unit 25, and the like.

  The detection control unit 21 determines the activation timing of the absolute position detection unit 30 and the detection timing of the absolute position detection unit 30 based on the information from the link information generation unit 22, and sends the absolute position detection unit 30 to the absolute position detection unit 30 at the detection timing. Execute absolute position measurement. In the present embodiment, the detection timing is a timing at which the user holding the mobile terminal 100 has moved a predetermined distance (for example, 30 m).

  The link information generation unit 22 is based on the detection results of the geomagnetic information detection unit 40 and the acceleration information detection unit 50 while the mobile terminal 100 is moving linearly (between a turn (bend corner) and a turn (bend angle)). The line segment information including the distance information is generated. That is, when the mobile terminal 100 moves from a certain point to a predetermined direction, the link information generation unit 22 generates line segment information that connects a certain point to a point where the moving direction is changed from the predetermined direction. get. Hereinafter, this line segment information is referred to as link information. Note that the link information generation unit 22 starts generating link information when the user holding the mobile terminal 100 starts walking, and receives a walking end command input from the user via the input interface 62. Then, the generation of link information is terminated. Further, the link information generation unit 22 instructs the detection control unit 21 to stop detection by the absolute position detection unit 30 when receiving a command to end the GPS application input from the input interface 62. Put out.

  The information storage unit 23 stores the link information generated by the link information generation unit 22 and the GPS measurement result detected by the absolute position detection unit 30 in a database. The movement route calculation unit 24 calculates a predetermined direction of movement based on the GPS measurement result detected by the absolute position detection unit 30 while the mobile terminal 100 is moving straight ahead, and uses the movement direction and link information. The travel route of the mobile terminal 100 is calculated from the included straight distance. The movement route calculation unit 24 reads link information and GPS measurement results from the information storage unit 23. The detailed contents of the database stored in the information storage unit 23 will be described later.

  The display control unit 25 acquires the movement route acquired by the movement route calculation unit 24 and displays it on the display screen 60.

  Next, processing in the mobile terminal 100 configured as described above will be described in detail based on FIGS. FIG. 4 is a flowchart showing a series of processes executed by the mobile terminal 100 in the movement route calculation process. As a premise of the processing in FIG. 4, it is assumed that an application for calculating a movement route has already been started under a user instruction.

  In the process of FIG. 4, first, the link information generation unit 22 determines whether or not the acceleration information detection unit 50 is activated in step S <b> 10. When the determination in step S10 is affirmed, the process proceeds to steps S11 and S12 and steps S14 to S28. The processes in steps S11 and S12 and the processes in steps S14 to S28 are performed in parallel. Each process will be specifically described below.

(About processing of steps S11 and S12)
In step S11, the link information generation unit 22 determines whether or not a bend has been detected. Here, the bending means that the user holding the mobile terminal 100 changes the traveling direction. For example, the link information generation unit 22 detects that there is a bend when the amount of change in geomagnetism detected by the geomagnetic information detection unit 40 exceeds a predetermined value.
Next, in step S12, a subroutine for link information acquisition processing is executed. The subroutine of the link acquisition process in step S12 is performed according to the flowchart of FIG. Specifically, first, in step S32 of FIG. 5, the link information generation unit 22 calculates the distance (link length) moved linearly based on the following equation (1).
Link length = (total number of steps when bending was detected
-The total number of steps when a previous turn was detected) x stride (1)

Here, the number of steps is a value acquired from a change in acceleration detected by the acceleration information detection unit 50, and the stride is a value set by the user. The user may input height instead of the stride. In this case, the link information generation unit 22 calculates an approximate stride from the input height. When the first turn is detected after starting to walk, the link information generation unit 22 calculates the distance (link length) of the linear movement based on the following equation (1) ′.
Link length = (total number of steps when bending is detected) x step length (1) '

  Next, in step S34, the link information generation unit 22 stores the link length calculated based on the above formula (1) or (1) ′ as the data for calculating the travel route in the information storage unit 23. Register in the database (see FIG. 6). Here, as shown in FIG. 6, the link database includes a “link No.” that is the serial number of the link, a “step number at the time of bending” that is the total number of steps of the user when the bending is detected, and a predetermined direction (for example, “Link angle”, which is an angle (counterclockwise angle) based on “north”, “link start point (x)”, “link start point (y)”, and link end point coordinates. Some items of “link end point (x)” and “link end point (y)” are included. In the stage immediately before step S20 is performed (the stage where the link No. 2 is acquired), the link No. 2 items of “link angle”, “link end point (x)”, and “link end point (y)” are left blank. In addition, link No. 2 "link start point (x)" and "link start point (y)" 1 is the same value as “link end point (x)” and “link end point (y)”.

  When the process of step S12 is completed as described above, the process returns to step S11 of FIG. 4, and link information is acquired each time the link information generation unit 22 detects a bend. Then, the processes in steps S11 and S12 are continued until the determination in step S28 is affirmed (until the end of walking).

(About processing of steps S14 to S28)
Next, the processes of steps S14 to S28 performed in parallel with the processes of steps S11 and S12 will be described. In step S14, the detection control unit 21 determines whether or not the user has walked a predetermined distance (here, 30 m). Here, the detection control unit 21 determines whether or not the user has walked for 30 m based on a value calculated from the product of the number of steps detected by the acceleration information detection unit 50 and the step length. However, not limited to this, the detection control unit 21 generally determines whether or not the user has walked for 30 m based on whether or not the time required for the user to walk for 30 m (for example, 23 seconds) has elapsed. It is good to do. The time required for walking 30 meters may be set in advance, or may be automatically set by the detection control unit 21 based on data relating to the number of steps acquired in the past. If the determination in step S14 is affirmative, the process proceeds to step S15.

  In step S <b> 15, the detection control unit 21 acquires an absolute position (referred to as an anchor point) via the absolute position detection unit 30. In the following, the anchor point is represented as “G (n)”, and the point on the link when the anchor point is acquired is represented as “P (n)” (for example, FIG. 9 (a), (See FIG. 9B).

  Next, in step S16, whether or not the detection control unit 21 has performed the process of step S12 of the link information generation unit 22 at least once before step S15 is performed, and whether or not information has been acquired for at least one link. Determine whether. If the determination is negative, the process returns to step S14, and thereafter, every time the user walks a predetermined distance, an anchor point is acquired. On the other hand, if the determination in step S16 is affirmative, the process proceeds to step S20. The anchor point data is stored in a GPS database as shown in FIG. The GPS database in FIG. 7 includes “link No.” that is the serial number of the link that was being acquired when the anchor point was measured, “latitude” and “longitude” that indicate the GPS positioning result, and the GPS acquisition time. The item “number of steps at the time of GPS acquisition” indicating the number of steps the user has walked from the beginning of walking is included. Note that in FIG. The state where the acquisition of the anchor point for the link “2” is completed is shown.

  Returning to FIG. 4, in step S <b> 20, the movement route calculation unit 24 uses the one piece of link information acquired in step S <b> 12 (link acquisition process) and the anchor point information acquired in step S <b> 15 (GPS acquisition process). Then, a link angle calculation process is performed. Hereinafter, the link angle calculation process of step S20 will be described along the flowchart of FIG.

(Link angle calculation process (step S20))
FIG. 8 is a flowchart showing the flow of processing in step S20. In the process of FIG. 8, first, in step S70, the movement path calculation unit 24 has a plurality of anchor points while the link information generation unit 22 acquires one link information in step S12. Is determined, that is, whether step S15 has been performed a plurality of times before step S12 is performed once. If the determination is negative, the process proceeds to step S72. If the determination is positive, the process proceeds to step S74.

  When the process proceeds to step S72, the movement path calculation unit 24 determines an angle at which the link passes the anchor point acquired from the end of the previous link as the link angle. Specifically, as shown in FIG. 9A, the angle at which the link passes through the anchor point G (1) starting from the end point F of the previous link is the link angle (for example, the angle with respect to the north). ) Determine as α.

  On the other hand, when the process proceeds to step S74, the movement route calculation unit 24 determines the link angle α ′ by weighting each anchor point. Hereinafter, as shown in FIG. 9B, a method of determining the link angle α ′ when three anchor points are acquired will be described.

  In the case of FIG. 9B, anchor points G (1), G (2), G (3) are acquired starting from the end F of the previous link, and each anchor point G (1), G ( 2) Assume that the positions (P (1), P (2), P (3)) on the link when G (3) is acquired are also acquired. In this case, P (1), P (2), and P (3) are calculated so that the value ε expressed by the following equation (2) is minimized.

Here, the above equation (2) assumes that there is a spring (spring constant k _j ) connecting each point between the point G (j) and the point P (j). This is an equation based on a theory (Kamada and Kawai model) that estimates a stable state, that is, a state where energy is minimum, as an optimal state. In the present embodiment, since the spring constant k _j is changed according to the weight of the anchor point, k _j is hereinafter referred to as a “weighting coefficient”.

In the above equation (2), in the present embodiment, the weighting factor k _j is set such that the anchor point is farther from the end F of the previous link (the start point of the current link) (that is, the anchor point is later in detection timing), Use a large value. For example, the weight coefficient k _j is set to a value proportional to the distance from the end F (the start point of the current link) of the previous link. In this way, the weight coefficient k _j is set to a larger value as the anchor point is farther away, as shown in FIG. 10, as the distance from the link start point to the anchor point is shorter, the error between the link start point and the GPS is larger. This is because the angle range a of the link passing through the range becomes large. That is, the closer the anchor point is from the link start point, the greater the influence on the link angle (see the left figure in FIG. 10), which widens the possible range of the link angle and has an effect on the error of the link angle. This is because it is necessary to reduce the influence as much as possible. Therefore, as in the present embodiment, the weighting factor k _j is increased for an anchor point that is farther from the end F (the starting point of the current link) of the previous link so that the influence on the calculation of the link angle is increased. Thus, an appropriate angle is calculated as the link angle.

FIG. 11A shows an example of the correct link angle and the link angle calculated by the movement route calculation unit 24 when the weighting factor is not used (or the weighting factor k _j is a fixed value). Has been. FIG. 11B shows an example of the correct link angle when the weighting factor is used (that is, when the weighting factor k _j is variable) and the link angle calculated by the movement route calculation unit 24. ing. Note that FIGS. 11A and 11B show a case where the anchor point is detected by being deviated from the actual position in a certain direction due to the influence of surrounding buildings (such as reinforcing bars).

  As can be seen by comparing FIG. 11 (a) and FIG. 11 (b), the link angle calculated by the movement route calculation unit 24 is more correct when the variable weighting coefficient is used as shown in FIG. 11 (b). Can be close to the link angle. Further, the end point of the link determined from the link angle and the link length can be brought close to the actual end point of the link.

  In the present embodiment, for example, as shown in FIG. 12, even when the start point of the link is deviated from the actual start point, by increasing the weighting factor according to the distance from the start point of the link, The calculated link angle can be brought close to the correct link angle. Further, the end point of the link determined from the link angle and the link length can be brought close to the actual end point of the link.

  When the link angle α or α ′ is determined as described above, the item “link angle” in the link database of FIG. 6 can be registered. Further, by determining the link angle α or α ′, it is possible to register the items in the link end points (x) and (y).

  After the process of step S72 or step S74 is performed as described above, the process proceeds to step S22 in FIG.

  Returning to FIG. 4, in step S <b> 22, the movement route calculation unit 24 calculates a movement route. Specifically, the movement route calculation unit 24 calculates, as a new movement route, a link obtained by connecting the link having the link angle obtained in step S20 to the movement route obtained so far.

  In step S <b> 26, the display control unit 25 outputs the movement route on the display screen 60. Thereby, on the display screen 60, the route on which the user has walked so far is displayed in almost real time.

  Next, in step S28, the link information generation unit 22 determines whether or not the walking has ended. If the determination is negative, the process returns to step S11 and step S14. Note that the case where the end of walking is determined in step S <b> 28 is, for example, a case where the acceleration information detection unit 50 has not detected the user's walk for a predetermined time, or a case where the user issues a walk end command from the input interface 62. This is the case when it is entered. On the other hand, if the determination in step S28 is affirmative, all the processes in FIG. 4 are terminated.

As described above in detail, according to the present embodiment, the absolute position detection unit 30 detects the anchor point (absolute position) of the mobile terminal 100 and the link information generation unit 22 waits for the mobile terminal 100 to bend. An anchor detected by the absolute position detection unit 30 while the mobile terminal 100 is moving on the link acquired by the link information generation unit 22. Based on the point, the link angle (direction) is calculated, and the movement route of the mobile terminal 100 is calculated from the link angle and the straight travel distance of the link. In this case, when a plurality of anchor points are detected by the absolute position detection unit 30 while the mobile terminal 100 is moving on one link, the movement route calculation unit 24 is detected at a later timing. For the calculation of the link angle, the weight coefficient k _{j of} each of the plurality of anchor points is increased for the anchor point. Thereby, in this embodiment, the link angle is increased by increasing the weight of the anchor point (anchor point detected at a later timing) that is less affected by the error when determining the link angle and is farther from the start point of the link. Can be brought closer to the correct angle. Therefore, it is possible to accurately calculate the movement route without using map information or the like. Further, according to the present embodiment, since it is not necessary to continue to acquire the absolute position frequently, the power consumption of the apparatus can be reduced. Moreover, in this embodiment, since a movement path | route is changed whenever the user who owns the mobile terminal 100 turns a corner, etc., a movement path | route is updated substantially in real time, and it is convenient.

  Further, in the present embodiment, the movement route calculation unit 24 uses the weight of each of the plurality of anchor points (absolute positions) as the distance that the mobile terminal 100 has moved on the link when each anchor point is acquired (that is, And a value proportional to the distance from the link start point). As a result, when the anchor point acquisition timing is determined by the distance (number of steps × step length) as in the present embodiment, the distance can be used to determine the weighting factor. This makes it possible to easily determine the weighting factor.

  In the above embodiment, each anchor point is weighted with a value proportional to the distance from the link start point when the anchor point is acquired. However, the present invention is not limited to this. Weighting may be performed with a value proportional to the order detected by the absolute position detection unit 30 while 100 is moving (the order of obtaining the absolute position corresponding to each link). In this case as well, weighting can be performed simply as in the case of weighting using distance as in the above embodiment.

  In the above embodiment, the case where the anchor point acquisition timing is determined by the distance (number of steps × step length) has been described, but the present invention is not limited to this. For example, it is good also as acquiring an anchor point for every predetermined time measured using a timer.

  In the above-described embodiment and the above-described modification, the case where the movement route is calculated using the sum of squares of the distance between the anchor point G (i) and the corresponding P (i) has been described. It is not limited to. For example, the link angle at which the sum of squares of the distance (shortest distance) between the anchor point G (i) and the link becomes the minimum value may be set as the optimum value.

  In the above embodiment, the case where the position in the GPS database is represented by latitude and longitude has been described. However, the latitude and longitude may be represented by other values (for example, a distance with the starting point as the origin). In this case, the positive direction of the x coordinate can be the east direction, and the positive direction of the y coordinate can be the north direction.

  In the above embodiment, the case where the movement route is calculated in the mobile terminal 100 has been described. However, the present invention is not limited to this. For example, in the mobile terminal 100, the detection results of the absolute position detection unit 30, the geomagnetic information detection unit 40, and the acceleration information detection unit 50 may be transmitted to an external server or the like. By giving the server the same function as that of the control unit 20 in FIG. 3, it is possible to calculate a movement route and a movement route in the server. In addition, the server may transmit the calculated travel route or travel route to the mobile terminal 100.

  In the above-described embodiment, a case where a GPS sensor is used as the absolute position detection unit 30 has been described. However, the present invention is not limited to this, and other devices may be used. As the absolute position detecting means, for example, an RFID system can be adopted. Moreover, in the said embodiment, it may replace with a geomagnetic sensor as the geomagnetic information detection part 40, and it is good also as using another direction sensor, for example, a gyro sensor.

  Note that the processing function of the control unit 20 in the present embodiment can be realized by a computer. In that case, a program describing the processing contents of the functions that the control unit 20 should have is provided. By executing the program on a computer, the above processing functions are realized on the computer. The program describing the processing contents can be recorded on a computer-readable recording medium.

  When the program is distributed, for example, it is sold in the form of a portable recording medium such as a DVD (Digital Versatile Disc) or a CD-ROM (Compact Disc Read Only Memory) on which the program is recorded. It is also possible to store the program in a storage device of a server computer and transfer the program from the server computer to another computer via a network.

  The computer that executes the program stores, for example, the program recorded on the portable recording medium or the program transferred from the server computer in its own storage device. Then, the computer reads the program from its own storage device and executes processing according to the program. The computer can also read the program directly from the portable recording medium and execute processing according to the program. Further, each time the program is transferred from the server computer, the computer can sequentially execute processing according to the received program.

  The above-described embodiment is an example of a preferred embodiment of the present invention. However, the present invention is not limited to this, and various modifications can be made without departing from the scope of the present invention.

In addition, the following additional notes are disclosed regarding the above description.
(Supplementary Note 1) Between the absolute position detection unit that detects the absolute position of the mobile terminal and the point where the moving direction is changed from the predetermined direction when the mobile terminal moves in a predetermined direction from the certain point. And calculating the predetermined direction based on the absolute position detected by the absolute position detection unit while the mobile terminal is moving in the predetermined direction; A travel route calculation unit that calculates a travel route of the mobile terminal from the calculated direction and the straight travel distance included in the line segment information, and the mobile terminal moves from the certain point in the predetermined direction. If the absolute position detection unit detects a plurality of the absolute positions while the absolute position detection unit detects the plurality of absolute positions in the calculation of the predetermined direction as the absolute position detected at a later timing. A mobile terminal characterized by increasing the weight of each paired position.
(Supplementary Note 2) The movement route calculation unit sets the weight of each of the plurality of absolute positions to a value proportional to the order detected by the absolute position detection unit while the mobile terminal is moving in the predetermined direction. The mobile terminal according to Supplementary Note 1, wherein
(Supplementary Note 3) The movement route calculation unit sets the weight of each of the plurality of absolute positions to a value proportional to the distance that the mobile terminal has moved from the certain point when the absolute positions are acquired. The mobile terminal according to Supplementary Note 1, wherein
(Supplementary Note 4) When the absolute position of the mobile terminal is acquired from an absolute position detection unit that detects the absolute position of the mobile terminal, and the mobile terminal moves in a predetermined direction from a certain point, the moving direction is determined from the certain point. The line segment information connecting between the direction and the point to be changed is acquired, and the predetermined position is determined based on the absolute position detected by the absolute position detection unit while the mobile terminal is moving in the predetermined direction. The computer calculates a direction and causes the computer to execute a process of calculating a movement route of the mobile terminal from the calculated direction and the straight-ahead distance included in the line segment information, and the mobile terminal starts the predetermined point from the certain point. If a plurality of the absolute positions are detected in the acquisition process while moving in the direction, the absolute position detected at a later timing is earlier in the process of calculating the movement path. A moving route calculation program for increasing the weight of each of the plurality of absolute positions in calculating the predetermined direction.
(Supplementary Note 5) In the process of calculating the movement route, the absolute position detection unit detects the weight of each of the plurality of absolute positions while the mobile terminal is moving in the predetermined direction. The moving path calculation program according to appendix 4, characterized in that the value is proportional to.
(Additional remark 6) In the process which calculates the said movement path | route, the distance which the said mobile terminal moved from the said certain point when each said absolute position was acquired to the said computer with the weight of each of these absolute positions. The travel route calculation program according to appendix 1, characterized in that the value is proportional to.

10 mobile terminal 22 link information generation unit (link acquisition unit)
24 travel route calculation unit 30 absolute position detection unit

Claims (7)

An absolute position detector for detecting the absolute position of the mobile terminal;
An acceleration detector for detecting an acceleration of the mobile terminal;
When the mobile terminal moves in a predetermined direction from a certain point, the length of a line segment connecting from the certain point to the point where the moving direction is changed from the predetermined direction is set to the detected change in acceleration. A line segment length calculation unit to calculate based on
While calculating the predetermined direction based on the absolute position detected by the absolute position detection unit while the mobile terminal is moving in the predetermined direction, the calculated direction and the length of the line segment From the above, the movement route calculation unit for calculating the movement route of the mobile terminal starting from the certain point,
With
When a plurality of absolute positions are detected by the absolute position detection unit while the mobile terminal is moving in the predetermined direction from the certain point,
The movement path calculation unit is configured to reduce the influence of the error of the absolute position on the calculation of the predetermined direction as the absolute position closer to the certain point. A mobile terminal characterized in that the travel route is calculated by reflecting the absolute position farther from a certain point in the direction of the travel route.   The movement path calculation unit calculates a sum of products of the absolute position, a square of a distance between the point on the line segment when the absolute position is detected or the line segment, and a weighting factor according to the absolute position. The mobile terminal according to claim 1, wherein the predetermined direction is calculated by obtaining an angle of the line segment to be minimized, and the weighting factor is increased as the absolute position is detected at a later timing.   The movement path calculation unit sets the weighting coefficient of each of the plurality of absolute positions to a value proportional to the order detected by the absolute position detection unit while the mobile terminal is moving in the predetermined direction. The mobile terminal according to claim 2, characterized in that:   The movement route calculation unit sets the weighting factor of each of the plurality of absolute positions to a value proportional to the distance that the mobile terminal has moved from the certain point when each of the plurality of absolute positions is acquired. The mobile terminal according to claim 2, wherein:   The line segment length calculation unit calculates the length of the line segment by calculating a product of the number of steps obtained from the detection result of the acceleration change and a predetermined step length. A mobile terminal according to any one of the above. An angular velocity detector that detects a change in angular velocity of the mobile terminal;
The mobile terminal according to claim 1, wherein the line segment length calculation unit determines that the moving direction has been changed based on a detected change in angular velocity. Obtaining the absolute position of the mobile terminal from an absolute position detection unit for detecting the absolute position of the mobile terminal;
Detecting the acceleration of the mobile terminal;
When the mobile terminal moves in a predetermined direction from a certain point, the length of a line segment connecting from the certain point to the point where the moving direction is changed from the predetermined direction is set to the detected change in acceleration. Based on
While calculating the predetermined direction based on the absolute position detected by the absolute position detection unit while the mobile terminal is moving in the predetermined direction, the calculated direction and the length of the line segment From the above, let the computer execute the process of calculating the movement route of the mobile terminal starting from the certain point,
When a plurality of absolute positions are detected by the absolute position detection unit while the mobile terminal is moving in the predetermined direction from the certain point,
In the process of calculating the movement route, the absolute position closer to the certain point is reduced among the detected absolute positions so that the influence of the error of the absolute position on the calculation of the predetermined direction is reduced. A moving route calculation program for calculating the moving route by reflecting the absolute position farther from the certain point in the direction of the moving route.

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