JP5445266B2 - Positioning device, locus information storage method, program - Google Patents

Description

  The present invention relates to a technique for storing trajectory data indicating its own movement trajectory in a positioning device.

  Conventionally, in a positioning device such as a navigation device that acquires position information (latitude, longitude, altitude) indicating its current position by receiving radio waves transmitted from a positioning satellite such as a GPS (Global Positioning System) satellite. Many of them have a function of storing the acquired position information as trajectory data indicating the movement trajectory of the positioning device.

  By the way, when storing the trajectory information including a series of trajectory data, if all the acquired position information is stored as trajectory data, the memory capacity required for storing the trajectory information increases. In this regard, for example, Patent Document 1 below discloses a technique for acquiring own movement direction in a predetermined cycle and storing trajectory data only when the integrated value of the obtained change amounts in the movement direction becomes larger than a threshold value. Have been described. That is, a technique for reducing the memory capacity necessary for storing the trajectory information by compressing the trajectory information by appropriately thinning out the trajectory data is described.

JP 2004-125542 A

  However, in the technique of Patent Document 1, each piece of trajectory data constituting the movement trajectory information is position information (latitude and longitude) indicating its current position on the map. Therefore, there is a problem that the trajectory information indicating the movement trajectory during a period in which the trajectory data cannot be thinned cannot be compressed.

  The present invention has been made in view of such conventional problems, and an object thereof is to efficiently compress and record trajectory information indicating a movement trajectory without thinning out trajectory data indicating the movement trajectory.

In order to solve the above-described problem, in the positioning device according to the first aspect of the present invention, positioning means for receiving a radio wave transmitted from a positioning satellite and measuring its current position, and its own movement trajectory Storage means for storing the indicated trajectory information, first storage control means for storing the position information measured by the positioning means as trajectory information in the storage means at a first time interval, and the first storage control. While the means stores the position information as trajectory information in the storage means at the first time interval, the position fluctuation indicating the amount of change in the current position during the second time interval at the second time interval. A second storage control unit that stores information as trajectory information in the storage unit; and a plurality of position fluctuations that the second storage control unit should continuously store in the storage unit as trajectory information at a second time interval. By information Addition means for adding the change amount shown on the condition that the change amount indicated by the position change information on the subsequent side satisfies a predetermined criterion, the second storage control means, The position variation information indicating the amount of variation after the addition by the adding unit is stored as trajectory information in the storage unit, instead of a plurality of pieces of position variation information to which the variation amount is added. To do.

In the positioning device according to the second aspect of the present invention, the adding means is configured such that the angle formed by the variation amount indicated by the positional variation information on the subsequent side is a threshold or less is a threshold value. Each of the fluctuation amounts indicated by the plurality of position fluctuation information is added on condition that a certain movement direction is expressed, and the reference movement direction is the position fluctuation stored immediately before as trajectory information in the storage means. The moving direction is represented by the fluctuation amount indicated by the information and the fluctuation amount not added by the adding means.

In the locus information storage method according to the third aspect of the present invention, positioning means for receiving a radio wave transmitted from a positioning satellite and measuring its current position, and locus information indicating its own movement locus And a storage device that stores the position information measured by the positioning device in the storage device as trajectory information at a first time interval, and the position at the first time interval. While the information is stored in the storage means as the trajectory information, the position fluctuation information indicating the fluctuation amount of the current position during the second time interval is stored as the trajectory information in the storage means at the second time interval. It shows a step of, the variation amount indicated by the plurality of positional variation information should continuously be stored as the locus information in the storage unit at a second time interval, the position change information of the subsequent side Adding the position fluctuation information indicating the fluctuation amount after the addition to a plurality of position fluctuation information to which the fluctuation amount is added. Instead, the information is stored in the storage means as trajectory information .

In the program according to the fourth aspect of the invention, positioning means for receiving a radio wave transmitted from a positioning satellite and measuring its own current position, and trajectory information indicating its own movement trajectory are stored. A first storage control means for storing position information measured by the positioning means in the storage means as trajectory information at a first time interval; While the storage control unit stores the position information as trajectory information in the storage unit at the first time interval, the amount of change in the current position during the second time interval is calculated at the second time interval. a second storage control means for storing the positional fluctuation information indicating the trajectory information in the storage means, the second storage control unit to be continuously stored as locus information in the storage unit at a second time interval Functioning as addition means for adding the fluctuation amount indicated by the positional fluctuation information of a number on condition that the fluctuation quantity indicated by the positional fluctuation information on the subsequent side satisfies a predetermined criterion, The storage control means stores the position fluctuation information indicating the fluctuation amount after addition by the addition means in the storage means as trajectory information instead of the plurality of position fluctuation information to which the fluctuation amount is added. Features.

  According to the present invention, it is possible to efficiently compress and record trajectory information indicating a movement trajectory without thinning out trajectory data indicating the movement trajectory.

It is a block diagram which shows the positioning apparatus which concerns on this invention. It is a conceptual diagram which shows the memory area ensured in RAM. It is a conceptual diagram which shows the data format of absolute coordinate data. It is a conceptual diagram which shows the data format of relative coordinate data. It is a flowchart which shows the processing content of CPU in a position measurement period. It is a flowchart which shows a locus | trajectory data preservation | save process.

  Hereinafter, an embodiment of the present invention will be described. The present embodiment relates to a portable positioning device that has a function of performing position measurement (positioning) using a GPS satellite and recording a movement trajectory.

  FIG. 1 is a block diagram showing an outline of the electrical configuration of the positioning device 1 of the present embodiment. As shown in FIG. 1, the positioning device 1 includes a control unit 2, a GPS module 3 connected to the control unit 2, a magnetic sensor 4, an acceleration sensor 5, a display 6, a key input unit 7, and a memory controller 8. It is configured.

  The GPS module 3 measures the current position by receiving radio waves transmitted from a plurality of GPS satellites (positioning satellites) by the GPS antenna 3a, and calculates position information indicating its current position, that is, latitude, longitude, and altitude. It is the positioning means in this embodiment which acquires the absolute coordinate position which becomes.

  The GPS module 3 includes a control circuit that demodulates and decodes the L1 band C / A code superimposed mainly on radio waves transmitted from positioning satellites and calculates the current position, and satellite information necessary for capturing the GPS satellites. And a memory for storing data related to the geodetic system indispensable for the calculation of the current position, and a clock circuit for counting the local time in the area where the positioning device 1 is used with high accuracy in order to obtain the capture timing of the GPS satellite. The

  The GPS module 3 supplies GPS data including the acquired absolute coordinate position to the control unit 2. Note that the GPS data includes a positioning time consisting of a date and hour and minute, and information indicating positioning accuracy. The information indicating the positioning accuracy is the current position measured this time is a three-dimensional position measurement result when four or more satellites can be captured when measuring the current position, or 2 when only three satellites can be captured. This is information indicating whether the result is a dimension position measurement result.

  The magnetic sensor 4 detects the geomagnetic component in the triaxial direction, and supplies the detection result to the control unit 2 as movement direction information indicating a movement direction (specifically, an azimuth angle) while the positioning device 1 is moving. . Although not shown, the output signal of the magnetic sensor 4 is amplified by an amplifier, converted into a digital detection signal by an A / D converter, and then supplied to the controller 2.

  The acceleration sensor 5 detects the acceleration in the triaxial direction in the positioning device 1 and supplies the detection result to the control unit 2 as movement amount information indicating the movement amount when the positioning device 1 moves. Although not shown, the output signal of the acceleration sensor 5 is also amplified by an amplifier, converted into a digital detection signal by an A / D converter, and then supplied to the control unit 2.

  The control unit 2 mainly includes a CPU (Central Processing Unit) 21, a ROM (Read Only Memory) 22, and a working RAM (Random Access Memory) 23. The control unit 2 controls the positioning device 1 according to various programs stored in the ROM 22. The ROM 22 causes the control unit 2 to perform processing to be described later, thereby causing the CPU 21 to function as a first storage control unit, a second storage control unit, an addition unit, and a determination unit in this embodiment. Is remembered.

  FIG. 2 is a conceptual diagram showing a storage area secured in the RAM 23 while the positioning device 1 records the movement trajectory. During the recording of the movement locus, the RAM 23 is secured with the magnetic sensor output data storage area 23a, the acceleration sensor output data storage area 23b, the GPS data storage area 23c, and the locus data storage area 23d. In the present embodiment, the RAM 23 functions as a storage unit by securing the locus data storage area 23d during recording of the movement locus.

  The detected value data supplied from the magnetic sensor 4 to the control unit 2 is stored in the magnetic sensor output data storage area 23a, and the acceleration sensor output data storage area 23b is supplied from the acceleration sensor 5 to the control unit 2. The detected value data is saved. GPS data such as latitude, longitude, altitude and positioning accuracy supplied from the GPS module 3 to the control unit 2 is stored in the GPS data storage area 23c.

  In the locus data storage area 23d, a series of locus data indicating the movement locus of the positioning device 1 is temporarily saved. There are two types of trajectory data temporarily stored in the trajectory data storage area 23d: absolute coordinate data and relative coordinate data.

  The absolute coordinate data is trajectory data indicating the absolute coordinate position on a map at a certain point, and is mainly data of GPS data acquired by the GPS module 3.

  FIG. 3 is a conceptual diagram showing a data format of the absolute coordinate data 101. As shown in FIG. 3, the absolute coordinate data 101 is 19-byte data including a data structure management area, an operation type management area, a time information area, and a position information area.

  3 bits are allocated to the data structure management area. In the data structure management area, data indicating the type of the trajectory data, the trajectory data being the absolute coordinate data 101, and identification data indicating the accuracy of the absolute coordinate data 101 (the positioning accuracy described above) are described. Is done.

  5 bits are allocated to the operation type management area. In the operation type management area, data indicating the type of operation of the positioning device 1, that is, the type of operation when the user of the positioning device 1 is in the moving state, in the stopped state, or in the moving state. Described. In this embodiment, the type of operation in the moving state is a state according to the moving speed, and the user of the positioning device 1 is walking, running, or riding a vehicle. One of them.

  6 bytes are allocated to the time information area. In the time information area, each year, month, day, hour, minute, and second data indicating the time when the position measurement is performed is described in 8 bits.

  12 bytes are allocated to the position information area. In the position information area, each data of the longitude area (X1 to X4), the latitude area (Y1 to Y4), and the altitude area (Z1 to Z4) is described in 32 bits. Data described in the position information area is data corresponding to the position information of the present invention.

  The relative coordinate data is trajectory data indicating the relative position of another point with respect to a certain point, and is mainly data calculated by the CPU 21 and the amount of change in the position within a certain time. . FIG. 4 is a conceptual diagram showing the data format of the relative coordinate data 102. As shown in FIG. 4, the relative coordinate data 102 is 6-byte data including a data structure management area, an operation type management area, a compression time management area, a unit management area, and a movement amount storage area. is there.

  Similar to the absolute coordinate data, 3 bits are assigned to the data structure management area, and identification data indicating that the trajectory data is the relative coordinate data 102 is described in the data structure management area. Similarly to the absolute coordinate data, 5 bits are allocated to the operation type management area, and data indicating the movement mode (user state) of the positioning device 1 described above is described in the operation type management area.

  10 bits are allocated to the compression time management area. The compression time management area is an area in which data representing the compression time of trajectory data, which will be described later, is described. The compression time is a time from 0 seconds to 1,023 seconds that can be expressed by 10 bits.

  3 bytes are allocated to the movement amount storage area, and the movement amount storage area has a relative movement amount (hereinafter referred to as a relative movement amount) in the X, Y, and Z directions with respect to a certain point as a reference. Each) is described. That is, the movement amount storage area is composed of three movement amount storage areas (movement amount storage area: X, movement amount storage area: Y, movement amount storage area: Z) in which the relative movement amounts in the three axis directions are individually described. Has been. In each area of the movement amount storage area, signed data that can be expressed in 1 byte, that is, a three-digit numerical value of −127 to 217 is described.

  6 bits are allocated to the unit management area, and data indicating the unit of the relative movement amount described in the movement amount storage area is described in the unit management area. That is, the unit management area is composed of three unit management areas (unit management area: X, unit management area: Y, unit management area: Z) in which units of relative movement amounts in the three-axis directions are individually described. . The unit described in each area of the unit management area is one of four types of units of 10 cm, 1 m, 10 m, and 100 m. Data described in the movement amount storage area and the unit management area is data corresponding to the position variation information of the present invention.

  On the other hand, the memory controller 8 is an input / output interface that controls data input / output between the data recording medium 9 that is various memory cards mounted on the positioning device 1 and the control unit 2 (CPU 21). On the data recording medium 9, a series of trajectory data once accumulated in the trajectory data storage area 23d of the RAM 23 is recorded at a predetermined timing.

  The display 6 includes, for example, a liquid crystal display panel and a drive circuit that drives the liquid crystal display panel according to display data supplied from the control unit 2 and displays various information on the liquid crystal display panel. The information displayed on the display 6 includes image information indicating a movement locus based on a series of locus data recorded on the data recording medium 9.

  The key input unit 7 includes a power switch and a plurality of operation switches. The operation state of the operation switch in the key input unit 7 is regularly scanned by the control unit 2 (CPU 21).

  Next, the operation | movement which concerns on this invention of the positioning apparatus 1 which consists of the above structure is demonstrated. First, an outline of position measurement (positioning) operation in the positioning device 1 will be described.

  The positioning device 1 stores the trajectory data composed of the absolute coordinate data or the relative coordinate data described above in the trajectory data storage area 23d of the RAM 23 while measuring the position at regular time intervals and sequentially measuring the self-position. In the present embodiment, the position measurement interval (positioning interval) is 1 second.

  In addition, the positioning device 1 repeats new trajectory data by transferring a series of trajectory data stored in the RAM 23 to the data recording medium 9 at any time when there is no more space in the trajectory data storage area 23d. Save to the data storage area 23d.

  In addition, during the position measurement, the positioning device 1 stores the absolute coordinate data as the trajectory data at a fixed time interval (first time interval) including the initial trajectory data. Relative coordinate data is repeatedly stored as trajectory data at a certain one second interval (second time interval).

  Further, the positioning device 1 performs linear compression to thin out the relative coordinate data according to a predetermined condition while repeatedly storing the relative coordinate data as the trajectory data. A specific method of linear compression will be described later.

  Hereinafter, specific operations in the positioning device 1 will be described with reference to FIGS. 5 and 6. 5 and 6 are flowcharts showing the processing contents executed by the CPU 21 in accordance with the trajectory data recording program 22a stored in the ROM 22 while the position measurement is being performed in the positioning device 1. FIG.

  As shown in FIG. 5, for example, the CPU 21 checks whether or not it is the storage timing of the absolute coordinate data after starting the position measurement by operating a predetermined operation switch by the user (step S <b> 1). The storage timing of the absolute coordinate data is a timing that comes immediately after the start of processing and at a predetermined time interval determined in advance during position measurement.

  Therefore, the CPU 21 immediately sets “1” to the absolute coordinate request flag F at the beginning of the processing (step S2), and then counts the fixed time T toward the next storage timing by RTC (Real-Time Clock). Start (step S3). The fixed time T is a time of about several minutes to 30 minutes.

  Subsequently, the CPU 21 performs movement measurement (step S4). The movement measurement is a process of detecting the movement direction and the movement amount of the positioning device 1 by the magnetic sensor 4 and the acceleration sensor 5. In the movement measurement, the CPU 21 acquires the detection value data of the magnetic sensor 4 and the detection value data of the acceleration sensor 5 a plurality of times within a fixed time of the positioning interval (1 second) or less, and the acquired detection value data is stored in the RAM 23. Are stored (accumulated) in the magnetic sensor output data storage area 23a and the acceleration sensor output data storage area 23b.

  The number of detection value data acquired at the time of movement measurement is the judgment of the type of operation of the positioning device 1 described above (stop state, state in which the user is walking, state in which the user is running, or state in which the vehicle is riding) The acquisition period and the number of acquisitions are sufficient for calculating the movement direction and the movement distance during movement of the positioning device 1 to be described later. For example, the number of detected value data acquired is 40 samples per second.

  After that, the CPU 21 determines the type of the current operation in the positioning device 1 based on the stored detection value data when the movement measurement (storage of the detection value data) ends (step S5: YES) (step S6). ). That is, the CPU 21 determines whether the user of the positioning device 1 is in a stopped state, a walking state, a running state, or a riding state. Note that the CPU 21 temporarily stores the determination result in the internal memory.

  Subsequently, the CPU 21 acquires GPS data (step S7). That is, the CPU 21 causes the GPS module 3 to perform a positioning operation, and stores the GPS data supplied from the GPS module 3 in the GPS data storage area 23 c of the RAM 23.

  Next, the CPU 21 performs locus data storage processing (step S8). In the trajectory data storage process, the absolute coordinate data 101 (see FIG. 3) or the relative coordinate data 102 (see FIG. 4) is stored in the trajectory data storage area 23d of the RAM 23 as trajectory data indicating the movement trajectory of the positioning device 1. It is processing. Details of the trajectory data storage process will be described later.

  Thereafter, the CPU 21 is in a state in which the trajectory data can be stored in the trajectory data storage area 23d (step S9: YES), and there is no instruction to end position measurement by a predetermined switch operation from the user (step S11: NO), the process of steps S1-S8 is repeated. The state in which the trajectory data can be stored in the trajectory data storage area 23d is a state in which a free area necessary for storing new trajectory data exists in the trajectory data storage area 23d.

  In addition, while repeating the processing of steps S1 to S8, the CPU 21 sets “1” to the absolute coordinate request flag F every time the storage timing of the absolute coordinate data comes (step S1: YES), and the next absolute The counting of the fixed time T toward the storage timing of the coordinate data is started again (step S3).

  Further, when the CPU 21 repeats the processes of steps S1 to S8, if there is no more space in the trajectory data storage area 23d to store new trajectory data (step S9: NO), the trajectory data storage area 23d at that time. A series of trajectory data stored in is transferred to the data recording medium 9 and recorded (step S10). The transfer (recording) of the series of trajectory data to the data recording medium 9 may be performed at regular intervals.

  Thereafter, the CPU 21 returns the processing of steps S1 to S8 again, and repeatedly stores new trajectory data in the trajectory data storage area 23d. And CPU21 complete | finishes a position measurement, when the completion | finish instruction | indication of the position measurement by predetermined switch operation is received from the user (step S11: YES).

  Next, details of the trajectory data storage process (step S8) will be described with reference to the flowchart of FIG.

  In the trajectory data saving process, when the GPS data has been successfully acquired in the process of step S7 (step S101: YES), first, the CPU 21 checks whether or not “1” is set in the absolute coordinate request flag F. (Step S102). That is, the CPU 21 confirms whether or not the data to be stored as the trajectory data is absolute coordinate data at the current processing timing (positioning timing).

  Immediately after the start of position measurement, “1” is set in the absolute coordinate request flag F (step S101: YES), so the CPU 21 uses the absolute coordinate data including the GPS data acquired in the process of step S7 as the first. As trajectory data, it is newly stored in the trajectory data storage area 23d of the RAM 23 (step S103).

  At this time, the CPU 21 describes the following data in each area shown in FIG. 3 of the absolute coordinate data. That is, the CPU 21 describes that the trajectory data is absolute coordinate data in the data structure management area and the identification data indicating the positioning accuracy, and the action type management area contains the action determined in step S6. Describe the data indicating the type (stopped, walking, running, or riding). Further, the CPU 21 describes the time data included in the GPS data acquired in step S7 in the time information area, and the position data included in the GPS data acquired in step S7 in the position information area. Describe.

  Thereafter, the CPU 21 resets the absolute coordinate request flag F to “0” (step S105). Thus, the CPU 21 completes the trajectory data storage process and returns to the main flow process of FIG.

  If the GPS module 3 has not succeeded in acquiring GPS data in the first trajectory data storage process immediately after the start of position measurement (step S101: NO), the trajectory data is not yet stored (step S106). : NO), the CPU 21 immediately stops the trajectory data storage process and proceeds to the process of step S3 in FIG. That is, in order to save the absolute coordinate data as the first trajectory data, the position measurement by the GPS module 3 is repeatedly executed.

  In addition, after saving the first trajectory data, the CPU 21 performs the following processing at a processing timing that is not the absolute coordinate data storage timing.

  First, when the GPS data has been successfully acquired (step S101: YES), the absolute coordinate request flag F has been reset to “0” (step S102: NO), so the CPU 21 is based on the GPS data. A relative movement amount is calculated for storage of the absolute coordinate data (step S105).

  The relative movement amount calculated by the CPU 21 in the process of step S105 is a relative movement amount in the X-axis direction, the Y-axis direction, and the Z-axis direction from the previous measurement position to the current measurement position. Therefore, for example, when the trajectory data stored as trajectory data at the previous processing timing is absolute coordinate data, the CPU 21 determines the measurement position indicated by the immediately previous absolute coordinate data stored in the trajectory data storage area 23d. The relative movement amount is calculated as a reference.

  In calculating the relative movement amount, the CPU 21 associates the change amount of longitude with the X axis, the change amount of latitude with the Y axis, and the change amount of altitude with the Z axis, and the X axis moves from south to north. Is assumed to be positive, Y-axis is positive from west to east, and Z-axis is positive from the sea level.

  Further, in the process of step S105, the CPU 21 uses the GPS data acquired this time at the next process timing in the process of step S105 or the process of step S7 described later, and the calculation position data indicating the previous measurement position. Is temporarily stored in the internal memory.

  On the other hand, if GPS data acquisition has failed at a processing timing that is not the absolute coordinate data storage timing (step S101: NO), the first trajectory data (absolute coordinate data) has already been saved, and the trajectory data has been saved. Since it is in the middle (step S106: YES), the CPU 21 performs the following processing.

  That is, the CPU 21 calculates the relative movement amount based on the plurality of detection value data of the magnetic sensor 4 and the plurality of detection value data of the acceleration sensor 5 stored in the RAM 23 in the movement measurement process (step S4) of FIG. (Step S107).

  The relative movement amount calculated by the CPU 21 in the process of step S107 is the relative movement amount in the X axis direction, the Y axis direction, and the Z axis direction between the self position at the previous process timing and the self position at the current process timing. It is.

  Here, the self position at the previous processing timing is the absolute coordinate data immediately before stored in the trajectory data storage area 23d at the previous processing timing, or temporarily stored in the internal memory in the processing of step S105 at the previous processing timing. This is the position indicated by the position data for calculation. Even in the process of step S107, the CPU 21 sets the amount of movement in the X-axis direction as the amount of change in longitude, the amount of movement in the Y-axis direction as the amount of change in latitude, and the amount of movement in the Z-axis direction as the amount of change in altitude. Correspondingly, the relative movement amount is calculated with the X axis as positive from south to north, the Y axis as positive from west to east, and the Z axis as positive from the sea level.

  In the process of step S107, the CPU 21 updates the above-described calculation position data temporarily stored in the internal memory at that time to data (absolute coordinate position) indicating the self position at the current process timing. Specifically, assuming that the calculation position data temporarily stored in the internal memory is (x, y, z) and the relative movement amounts are x (t), y (t), z (t), the CPU 21 The position data for calculation is updated to (x + x (t), y + y (t), z + z (t)). Here, the updated calculation position data is obtained by calculating the relative movement amount at the above-described step S105 when the GPS data acquisition is successful at the next processing timing, or the GPS data acquisition succeeding at the next processing timing. It is used when calculating the relative movement amount by the process of step S107 when not.

  Then, as described above, after calculating the relative movement amount by the processing of step S105 or step S107, the CPU 21 determines whether or not to perform linear compression (step S108). The linear compression is a process for thinning out the trajectory data as described above, that is, for reducing the number of recorded trajectory data. Specific contents of the linear compression and criteria for determining whether or not to perform the linear compression will be described later. However, in the second trajectory data storage process after the start of position measurement, the CPU 21 determines that linear compression should not be performed regardless of the above-described determination criteria (step S108: NO), and performs the following processing. .

  First, the CPU 21 uses the relative coordinate vector used when determining whether or not to perform linear compression in the subsequent trajectory data storage processing based on the relative movement amount in the three-axis direction calculated in the processing in step S105 or step S107. (Hereinafter referred to as reference vector data) is temporarily stored in the internal memory (step S109).

  Next, the CPU 21 newly stores the relative coordinate data indicating the relative movement amount calculated in the process of step S105 or step S107 as the trajectory data in the trajectory data storage area 23d of the RAM 23 (step S110). At this time, the CPU 21 describes the following data in each area shown in FIG. 4 of the relative coordinate data.

  That is, the CPU 21 describes identification data indicating that the trajectory data is relative coordinate data in the data structure management area, and the action type (stop state) determined in step S6 in the action type management area. , A state of walking, a state of running, or a state of riding a vehicle). Further, the CPU 21 describes “0 second” as the compression time in the compression time management area, and describes the relative movement amount calculated in the process of step S105 or step S107 in the movement amount area. In the management area, data indicating a unit of the relative movement amount is described.

  Thus, the CPU 21 completes the trajectory data storage process and returns to the main flow process of FIG.

  On the other hand, in the trajectory data storing process after the third time after the position measurement is started, the CPU 21 calculates the relative movement amount by the process of step S105 or step S107, and then performs the first and second compression described below. It is determined whether linear compression should be performed based on whether or not both conditions are satisfied (step S108).

  That is, the CPU 21 determines that linear compression should be performed when both the first and second compression conditions are satisfied, and when not satisfying at least one of the first and second compression conditions, Judge that linear compression should not be performed.

  The first compression condition is indicated by a movement vector (movement direction) represented by the relative movement amount calculated by the processing in step S105 or step S107, and reference vector data temporarily stored in the internal memory at that time. The angle formed with the reference vector (movement direction) is equal to or smaller than a threshold value and is smaller than a predetermined angle. The threshold is a small angle such that the movement directions can be determined to be substantially equal, for example. The reference vector data is a movement vector indicated by the relative movement amount in the three-axis directions stored in the process of step S109 performed immediately before as described above.

  Further, the second compression condition is that the type of operation at the current processing timing (during the previous trajectory data storage process) is the same as the type of operation at the previous processing timing. The type of operation at the current processing timing is the type of operation temporarily stored in the internal memory, and the type of operation at the previous processing timing is relative coordinate data stored as trajectory data at the previous processing timing. Is the type of action described in.

  If the CPU 21 determines that linear compression should not be performed in accordance with the above-described determination criteria (step S108: NO), the CPU 21 performs the above-described steps S109 and S110. That is, the CPU 21 temporarily stores the relative movement amount acquired at the current processing timing as reference vector data in the internal memory (step S109), and then directly stores the relative coordinate data indicating the relative movement amount acquired at the current processing timing as a locus. Newly saved as data (step S110). Thereafter, the CPU 21 completes the trajectory data storage process and returns to the main flow process of FIG.

  On the other hand, when the CPU 21 determines that linear compression should be performed in accordance with the above-described determination criteria (step S108: YES), the compression time of the trajectory data up to the present is the compression time management of the relative coordinate data. It is determined whether or not the maximum compression time that can be described in the work area has been reached (step S111).

  That is, in the processing of step S111, the CPU 21 determines whether “1,023 seconds” is described in the compression time management area of the relative coordinate data immediately before stored in the trajectory data storage area 23d of the RAM 23 at the previous processing timing, for example. Determine whether.

  If the compression time of the trajectory data up to the present has not reached the maximum compression time (step S111: NO), the CPU 21 first compares the relative coordinates immediately before being stored in the trajectory data storage area 23d of the RAM 23 at the previous processing timing. Calculation is performed to add the relative movement amount in the triaxial direction actually acquired at the current processing timing to the relative movement amount in the triaxial direction indicated by the data (step S112).

  That is, the CPU 21 sets x (t−1), y (t−1), and z (t−1) as the relative movement amounts in the three-axis directions indicated by the relative coordinate data stored at the previous processing timing, and this time. X (t-1) + x (t), y (t-1) + y () where x (t), y (t), and z (t) represent the actual relative movement amounts acquired at the processing timing in the three axes. t), z (t-1) + z (t) are acquired.

  Thereafter, the CPU 21 overwrites the previous relative coordinate data with the relative coordinate data indicating the amount of relative movement in the three-axis direction after the addition, and stores it in the trajectory data storage area 23d of the RAM 23 (step S113). In the process of step S113, the CPU 21 sets the compression time described in the compression time management area of the previous relative coordinate data in the compression time management area of the relative coordinate data to be overwritten on the previous relative coordinate data. Describes the compression time obtained by adding 1 second, which is the positioning interval. As a result, the trajectory data for one time is thinned out. That is, linear compression is performed by the processing of step S112 and step S113. Thereafter, the CPU 21 completes the trajectory data storage process and returns to the main flow process of FIG.

  On the other hand, even when the CPU 21 determines that linear compression should be performed after calculating the relative movement amount in the three-axis directions in the processing of step S105 or step S107 (step S108: YES), When the compression time of the trajectory data has already reached the maximum compression time at the processing timing (step S111: YES), the processing of step S109 and step S110 described above is performed.

  That is, as described above, the CPU 21 temporarily stores the relative coordinate data indicating the relative movement amount in the three-axis directions calculated at the current processing timing as reference vector data in the internal memory (step S109), and then the current processing timing. Relative coordinate data indicating the relative movement amount acquired in step 1 is newly stored as trajectory data as it is (step S110).

  Thereafter, the CPU 21 repeatedly executes a series of processes including the trajectory data storage process (FIG. 6) described above.

  As described above, a series of trajectory data recorded on the data recording medium 9 during the position measurement is displayed in the recording order (storage order) by the CPU 21 when the positioning device 1 displays an image showing the movement trajectory on the display 6. Read out. At that time, the CPU 21 displays, for example, a plurality of positions indicated by the respective locus data by dots on a map displayed on the display 6 or a plurality of positions indicated by the respective locus data by lines in the recording order. By connecting them, the movement trajectory is displayed on the display 6.

  Further, when displaying the movement locus, when the locus data is the relative coordinate data described above, the CPU 21 sets the coordinate position corresponding to each relative coordinate data to the absolute coordinate data stored immediately before each relative coordinate data. It calculates | requires by the calculation on the basis of the coordinate position shown by these. That is, the CPU 21 sequentially adds the movement amounts in the three axis directions indicated by the series of relative coordinate data following the absolute coordinate data to the coordinate positions in the three axis directions indicated by the absolute coordinate data, thereby obtaining a series of relative coordinate data. The coordinate positions corresponding to are sequentially calculated.

  Here, as described above, in the positioning device 1 according to the present embodiment, when the trajectory data is recorded during the position measurement, the absolute coordinates are used as the trajectory data at the positioning timing every certain time T (several minutes to about 30 minutes). Data is stored, and relative coordinate data having a data amount smaller than that of absolute coordinate data is stored as trajectory data at other positioning timings.

  Therefore, by reducing the amount of individual trajectory data that is periodically saved within a certain period of time, excluding the trajectory data that is saved at regular intervals, the trajectory indicating the trajectory can be moved without thinning out the trajectory data. It is possible to efficiently compress and record the trajectory information indicating.

  In this embodiment, when the relative coordinate data is stored as the trajectory data, the angle formed by the CPU 21 with the reference vector (movement direction) indicated by the reference vector data temporarily stored in the internal memory is a threshold value. Linear compression was performed on the following relative coordinate data, and trajectory data was thinned out. Therefore, the trajectory information indicating the movement trajectory can be recorded with higher compression efficiency by reducing the number of trajectory data to be recorded.

  In the present embodiment, the case where the reference vector is a three-dimensional movement direction vector represented by the relative movement amount in the three-axis directions indicated by the relative coordinate data has been described. However, the reference vector may be a two-dimensional movement direction vector represented by a relative movement amount in the X-axis direction and the Y-axis direction indicated by the relative coordinate data.

  Furthermore, when the trajectory data is thinned out in the implementation of the present invention, the trajectory data may be thinned out by a method different from the present embodiment, for example, the method described as the background art. Even in this case, the trajectory information indicating the movement trajectory can be recorded with higher compression efficiency.

  On the other hand, in the present embodiment, when the relative coordinate data is stored as the trajectory data, linear compression is performed on condition that the type of operation at the current processing timing and the previous processing timing is the same. For this reason, the position immediately after the type of operation changes, for example, the locus data indicating the position immediately after the user of the positioning device 1 changes from the stopped state to the starting state, that is, the position immediately after the movement distance has largely changed. The trajectory data shown can be recorded reliably.

  Furthermore, in the present embodiment, when the relative coordinate data is stored as the trajectory data, linear compression is performed on the condition that the compression time of the trajectory data up to the present has not reached the maximum compression time. That is, the number of relative coordinate data to be subjected to linear compression (the number of additions of the relative movement amount) is limited. Thereby, the precision of the coordinate position shown by the relative coordinate data recorded as locus data can be improved.

  In the present embodiment, when GPS data can be acquired at the processing timing (positioning timing) for storing relative coordinate data as trajectory data, the relative movement amount acquired based on the GPS data unconditionally is included. Coordinate data was saved. However, in carrying out the present invention, the CPU 21 may perform the following processing.

  For example, when the GPS data can be acquired at the processing timing for storing the relative coordinate data, the CPU 21 determines whether the accuracy (positioning accuracy) of the GPS data is high, that is, whether the GPS data is a three-dimensional position measurement result. Confirm further. And when the accuracy of GPS data is high, CPU21 performs the process which preserve | saves the relative coordinate data containing the amount of relative movement acquired based on GPS data. Conversely, when the accuracy of the GPS data is low, that is, when the GPS data is a two-dimensional position measurement result, the CPU 21 performs a plurality of detection value data of the magnetic sensor 4 and a plurality of detection value data of the acceleration sensor 5. A process of storing relative coordinate data including the relative movement amount acquired based on the above may be performed.

  Also, when the type of relative coordinate data is changed according to the accuracy of GPS data as described above, the accuracy of GPS data is not the type of position measurement result determined by the number of satellites captured during position measurement, but the rate of decrease in positioning accuracy. DOP (Dilution of Precision) which is a numerical value indicating

  In the present embodiment, the case where the present invention is applied to the portable positioning device 1 has been described. However, the present invention is also applied to a positioning device built in an electronic device such as a digital camera, a mobile phone terminal, or a wristwatch. Can be applied.

DESCRIPTION OF SYMBOLS 1 Positioning device 2 Control part 3 GPS module 3a GPS antenna 4 Magnetic sensor 5 Acceleration sensor 21 CPU
22 ROM
22a Trajectory data recording program 23 RAM
23a Magnetic sensor output data storage area 23b Acceleration sensor output data storage area 23d Trajectory data storage area 101 Absolute coordinate data 102 Relative coordinate data

Claims (4)

Positioning means for receiving radio waves sent from positioning satellites and measuring their current position;
Storage means for storing trajectory information indicating its own movement trajectory;
First storage control means for storing position information measured by the positioning means in the storage means as trajectory information at a first time interval;
While the first storage control means stores the position information in the storage means as trajectory information at the first time interval, the current position of the current position during the second time interval at the second time interval. Second storage control means for storing position fluctuation information indicating a fluctuation amount in the storage means as trajectory information ;
The amount of variation indicated by a plurality of position variation information that the second storage control unit should continuously store as trajectory information in the storage unit at a second time interval is indicated by position variation information on the subsequent side. Adding means for adding on the condition that the variation amount satisfies a predetermined criterion,
The second storage control unit stores position variation information indicating the variation amount after addition by the addition unit as trajectory information in the storage unit, instead of a plurality of position variation information to which the variation amount is added. positioning apparatus comprising the letting. The adding means is based on the plurality of position variation information on the condition that the variation amount indicated by the position variation information on the subsequent side represents a movement direction in which an angle with a reference movement direction is equal to or less than a threshold value. Add each said amount of variation shown,
The reference moving direction is represented by the fluctuation amount indicated by the position fluctuation information stored immediately before as the trajectory information in the storage means and not added by the addition means. It is a moving direction. The positioning apparatus of Claim 1 characterized by the above-mentioned. In a positioning device comprising a positioning means for receiving a radio wave sent from a positioning satellite and measuring its current position, and a storage means for storing trajectory information indicating its own movement trajectory,
Storing the position information measured by the positioning means as trajectory information in the storage means at a first time interval;
While the position information is stored as trajectory information in the storage means at the first time interval, position variation information indicating the amount of variation of the current position at the second time interval while the second time elapses. Storing in the storage means as trajectory information ;
The fluctuation amount indicated by a plurality of position fluctuation information to be continuously stored as trajectory information in the storage means at the second time interval is determined in advance as the fluctuation quantity indicated by the position fluctuation information on the subsequent side. And a step of adding on condition that the above-mentioned criteria are satisfied,
A trajectory information storage method characterized in that position variation information indicating the amount of variation after addition is stored as trajectory information in the storage means instead of a plurality of pieces of position variation information to which variation amounts are to be added . A computer having a positioning device that includes a positioning unit that receives radio waves transmitted from a positioning satellite and measures its current position and a storage unit that stores trajectory information indicating its own trajectory.
First storage control means for storing position information measured by the positioning means in the storage means as trajectory information at a first time interval;
While the first storage control means stores the position information in the storage means as trajectory information at the first time interval, the current position of the current position during the second time interval at the second time interval. Second storage control means for storing position fluctuation information indicating a fluctuation amount in the storage means as trajectory information;
The amount of variation indicated by a plurality of position variation information that the second storage control unit should continuously store as trajectory information in the storage unit at a second time interval is indicated by position variation information on the subsequent side. Function as an adding means for adding on the condition that the variation amount satisfies a predetermined criterion;
The second storage control unit stores position variation information indicating the variation amount after addition by the addition unit as trajectory information in the storage unit, instead of a plurality of position variation information to which the variation amount is added. A program characterized by letting

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