JP6541904B1 - Mobile terminal and present position correction system - Google Patents

Abstract

When the current position of the close proximity communication device can be trusted from the own terminal, the current position of the close communication device is used to correct the error of the current position of the own terminal to be smaller. The portable device 10 stores the current position information and the estimation error of the current position information, and the short distance communication which receives the current position information and the error information in the portable device 20 when the portable device 10 approaches the portable device 20. If the estimation error stored in the processing unit 14 and the present condition information storage unit 19 is larger than the estimation error obtained from the portable device 20, the present condition information storage unit 19 is corrected with the current position information and the estimation error obtained from the portable device 20 And a correction unit 15 that executes a correction process to be performed. However, the correction unit 15 does not execute the correction process when both the estimation error stored in the current state information storage unit 19 and the estimation error acquired from the mobile device 20 exceed the error threshold. [Selected figure] Figure 3

Description

  The present invention relates to mobile terminals and current position correction systems, and in particular to the positioning of the current position of mobile terminals.

  PDR (Pedestrian Dead Reckoning: Pedestrian Dead Reckoning: Pedestrian Dead Reckoning) is one of methods for positioning the current position indoors where it is difficult or impossible for GPS (Global Positioning System) radio waves to reach. The PDR estimates, for example, the position of the pedestrian from sensor values of a smartphone carried by the pedestrian. Specifically, by estimating the traveling distance from the value of the acceleration sensor and the traveling direction from the value of the magnetic sensor, the movement destination from the starting point is relatively estimated. As described above, PDR has an advantage that it is not necessary to install transmitting devices (beacons) in a mesh shape indoors as in position estimation technology using a beacon, and position estimation can be performed with a single smartphone.

JP 2013-201301 A JP, 2010-183262, A JP 2005-300415 A Japanese Patent Application Publication No. 2014-529947 JP, 2013-152097, A JP 2012-207996 Unexamined-Japanese-Patent No. 2010-12869 JP, 2002-152798, A JP, 2015-225455, A JP, 2016-29548, A

  On the other hand, since errors in sensor data can not be self-corrected with PDR alone, errors accumulate as estimations are repeated, and there is a disadvantage that correct positioning can not be performed eventually.

  Therefore, it is also conceivable to correct the current position of the own device using the current positions of other communication devices. That is, when approaching with another communication device, the current position is acquired from the other communication device, and the current position of the own device is updated with the current position to correct the current position of the own device.

  However, when another communication device is performing positioning using PDR, the error may be accumulated in the current position of the other communication device, and it may be assumed that positioning can not be performed correctly. Therefore, even if the current position of another communication device is acquired, it may not always be possible to correct the current position of the own device.

  An object of the present invention is to correct the error of the current position of the own terminal to be smaller by using the current position of the near-field communication device when the current position of the near-field communication device in proximity can be trusted more than the own terminal. I assume.

A mobile terminal according to the present invention estimates a current position based on storage means for storing current position information and error information, current position information stored in the storage means, and a measurement value by a mounted sensor. Current position estimation means for updating the current position information stored in the storage means with current position information indicating the estimated current position, and an error of the current position information stored in the storage means is estimated and estimated Error estimation means for updating the error information stored in the storage means with error information indicating an error, and current position information in the short distance communication device from the short distance communication device when the short distance communication device approaches Receiving means for receiving error information, at least one of the error information stored in the storage means and the error information received by the receiving means is equal to or less than a preset first threshold value In this case, as a result of comparing the error information stored in the storage means with the error information received by the receiving means, the error of the current position information of the own terminal is larger than the error of the current position information of the short distance communication device A correction unit that executes a correction process for correcting the current position information and the error information stored in the storage unit by updating the current position information and the error information acquired from the short distance communication device; have a, the correction means, in a case where more than a first threshold and the error information error information and the receiving means are stored in the storage unit has received are both set in advance, stored in the storage means The distance between the own terminal and the near-field communication device obtained from the current position information being received and the present position information received by the receiving means is closer to the near-field communication device. If the distance less regarded, the error information stored in the storage means is for updated at a predetermined value less than the first threshold value.

  Further, the predetermined value is zero or a predetermined value close to zero.

  Further, a value for determining whether or not the error of the current position information indicated by the error information can be trusted is set in the first threshold.

  Further, the storage unit further stores reception destination information, and the correction unit indicates a short distance communication device whose position is indicated by the current position information received by the reception unit when the correction process is performed. The receiver information stored in the storage unit is updated with the device information.

  In addition, the correction unit may perform the correction processing when the priority set corresponding to the reception destination information stored in the storage unit exceeds the priority set corresponding to the device information. Do not run.

  Further, the priority is set to be higher for the near-field communication device fixedly installed than for the near-field communication device not fixedly installed.

A present position correction system according to the present invention includes a mobile terminal carried by a user, and a short distance communication device performing short distance wireless communication with the mobile terminal, and the mobile terminal includes current position information. And storage means for storing error information, the current position is estimated based on the current position information stored in the storage means and the measurement value by the mounted sensor, and the current position information indicating the estimated current position At least one of the current position estimation means for updating the current position information stored in the storage means, the error information stored in the storage means, and the error information received by the receiving means is equal to or less than a preset first threshold In the above case, the error of the current position information stored in the storage means is estimated, and the error information stored in the storage means is updated with the error information indicating the estimated error. A difference estimation means, a receiving means for receiving current position information and error information in the short-distance communication device from the short-distance communication device when in proximity to the short-distance communication device, and the error information stored in the storage means And the error information received by the receiving means, when it is determined that the error of the current position information of the own terminal is larger than the error of the current position information of the short-distance communication device, it is acquired from the short-distance communication device and correcting means for performing a correction process for correcting by updating the current position information and error information stored in said storage means at the current position information and the error information, the possess, said correcting means, said storage means In the case where both the stored error information and the error information received by the receiving means exceed a preset first threshold, the current position stored in the storage means If the distance between the own terminal obtained from the information and the current position information received by the receiving unit and the near-field communication device is equal to or less than the distance for which the own terminal is considered to be close to the near-field communication device The stored error information is updated with a predetermined value less than the first threshold .

  According to the present invention, when the current position of the near-field communication device in proximity can be trusted more than the own terminal, the current position of the near-field communication device is used to correct the current position of the own terminal to be smaller. Can.

FIG. 1 is an overall configuration diagram showing an embodiment of a current position correction system according to the present invention. It is a hardware block diagram of the portable apparatus in this Embodiment. It is a figure which shows the block configuration of the portable apparatus in this Embodiment. It is a figure which shows an example of a data structure of the present condition information set to the present condition information storage part in this Embodiment. It is a figure which shows the data structural example of the priority information in this Embodiment. It is a flowchart which shows the update process of the present positional information in this Embodiment. It is a part of flowchart which shows the correction | amendment process of the present positional information in this Embodiment. It is a flowchart which shows the correction process following FIG. 7A.

  Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

  FIG. 1 is an entire configuration diagram showing an embodiment of a current position correction system according to the present invention. In FIG. 1, two mobile devices 10 and 20 are shown as mobile terminals. In the present embodiment, a case where a smartphone is used as the mobile devices 10 and 20 will be described as an example. Of course, as long as the communication terminal device has a short distance communication function and is portable, it may be another device such as a tablet terminal. The portable devices 10 and 20 are carried by users A and B moving in the facility. Although only two portable devices 10 and 20 necessary for explanation are illustrated in FIG. 1, the number of portable devices 10 and 20 may be three or more.

  FIG. 2 is a hardware configuration diagram of the portable devices 10 and 20 in the present embodiment. The portable devices 10 and 20 according to the present embodiment can be realized by a general-purpose hardware configuration that includes a computer and is conventionally present. That is, as shown in FIG. 2, the portable devices 10 and 20 have a CPU 1, a ROM 2, a RAM 3, a storage 4, a short distance wireless communication interface (IF) 5 for performing short distance wireless communication, and a liquid crystal panel 6 as a user interface. And various sensors 7 connected to the internal bus 8. The various sensors 7 include an acceleration sensor, an angular velocity sensor (gyro sensor), an air pressure sensor, a magnetic sensor, and the like.

  FIG. 3 is a block diagram showing the portable device 10 according to the present embodiment. Although only the block configuration of the portable device 10 is illustrated in FIG. 3 for the sake of convenience, the portable device 20 also has the same configuration. Here, the portable device 10 will be described as a representative.

  The portable device 10 includes a PDR calculation unit 11, a current position estimation unit 12, an error estimation unit 13, a short distance communication processing unit 14, a correction unit 15, a control unit 16, a PDR data storage unit 17, a device information storage unit 18, and current information A storage unit 19 is provided. The components not used in the description of the present embodiment are omitted from FIG.

  The PDR calculation unit 11 calculates the moving distance and the traveling direction from the starting point (the current position) by performing positioning according to pedestrian autonomous navigation (PDR) based on the measurement values by the various sensors 7, and calculates the calculated moving distance and The relative moving destination from the starting point (the current position) is estimated based on the traveling direction, and stored in the PDR data storage unit 17.

  The current position estimation unit 12 estimates the current position based on the current position information stored in the current condition information storage unit 19 and the movement distance and the traveling direction estimated by the PDR calculation unit 11 and indicates the current position indicated by the estimated current position. The current position information stored in the current state information storage unit 19 is updated with the information.

  The current position information is information indicating the current position of the mobile device 10. In addition, since the portable device 10 is carried and moved by the user A, the current positions of the portable device 10 and the user A are the same. That is, the “current position of the user A” and the “current position of the portable device 10” are synonymous. As described later, the current position is represented by the floor on which the user A is present and the position (coordinate data) on the floor. The current position information can be obtained by estimation by the current position estimation unit 12, but the error estimation unit 13 estimates an error of the current position information stored in the current status information storage unit 19, and is an error information indicating the estimated error. The estimation error stored in the current condition information storage unit 19 is updated.

  The near field communication processing unit 14 performs near field communication with the near field communication device when the near field communication device approaches. "Short-range communication device" refers to a device equipped with a function for performing short-distance wireless communication. In this embodiment, as the short-distance communication device, the portable device 20 which is moved by being carried by the user, the mobile terminal which moves autonomously, and the terminal are attached and installed at a known location, that is, fixedly installed. It is assumed that devices such as beacons using BLE (Bluetooth (registered trademark) Low Energy) technology are used. When the near-field communication processing unit 14 approaches the near-field communication device, specifically, when the near-field communication device approaches the near-field communication device, the near-field communication device 14 The current position information and the error information in the short distance communication device are received. In addition, since the position of the beacon is fixed, installation position information indicating the installation position of the beacon corresponds to the current position information. When the beacon itself has a function of transmitting the installation position information, the short distance communication processing unit 14 receives the installation position information transmitted by the beacon. If the beacon does not have the function of transmitting the installation position information by itself, the short distance communication processing unit 14 acquires the beacon installation position information from, for example, a known external database. In any case, the following description will be given assuming that the short distance communication processing unit 14 receives (acquires) the installation position information from the beacon for convenience. Furthermore, when the short distance communication processing unit 14 approaches the short distance communication device, the short distance communication processing unit 14 transmits the current position information and the error information stored in the current status information storage unit 19 to the short distance communication device. The close proximity state may occur when the portable device 10 moves by itself, when the near-field communication device to be communicated with is moved and approaches the portable device 10, or when both are moving.

  As a result of comparing the error information stored in the current state information storage unit 19 with the error information received by the short distance communication processing unit 14, the correction unit 15 compares the error of the current position information of the portable device 10 with that of the short distance communication device. If it is determined that the error is larger than the error of the current position information, the correction is performed by updating the current position information and error information stored in the current information information storage unit 19 with the current position information and error information acquired from the short distance communication device Execute the process However, the correction unit 15 executes the correction process when both the error information stored in the current state information storage unit 19 and the error information received by the short distance communication processing unit 14 exceed the first threshold set in advance. do not do.

  The control unit 16 controls the operation of each of the components 11 to 15 described above.

  The PDR data storage unit 17 stores the movement distance and the traveling direction obtained by the PDR calculation unit 11. The device information storage unit 18 stores information on various sensors 7 mounted on the mobile device 10. The information on the various sensors 7 includes the type and number of sensors mounted on the portable device 10, information on the performance of the various sensors 7, and the like. The device information storage unit 18 may store information related to the mobile device 10, specifically, information that can specify a model such as a model number of the mobile device 10. And the information regarding various sensors 7 may be acquired from the outside from this information.

  FIG. 4 is a view showing an example of the data configuration of the present condition information set in the present condition information storage unit 19 in the present embodiment. The current position information, the estimation error, and the correction information are set in the current state information as the information on the current position of the mobile device 10. The current position information is information indicating the current position of the portable device 10, and information (X coordinate and Y coordinate) representing the position in the facility in two dimensions (plane) and the floor number (floor) which can be specified by Z coordinate data And consists of. In the present embodiment, as illustrated in FIG. 4, the Z coordinate data is represented by the number of floors in which the user A is present. Although the current position of the user A is obtained by estimation, the estimation error is error information indicating an error of the current position estimated to be generated by this estimation.

  The correction information includes information related to the current position information and the correction when the estimation error is corrected. In the present embodiment, the correction time, the correction method, and the correction partner are included. The correction time is time information when current position information and an estimation error are corrected. In the present embodiment, only time is handled, but the format for representing time such as including date is not limited to this. The correction method is information indicating how the current position information has been corrected. In the present embodiment, the case where the current position information is corrected by the current position information acquired by passing communication with the short distance communication device (the portable device 20) and the case where the current position information is corrected by the current position information (installation position information) of the beacon are described. As assumed, "passing" or "beacon" is set as the correction method. In the present embodiment, “passing communication” refers to communication performed mutually when the users A and B carrying the portable devices 10 and 20 pass each other and the portable devices 10 and 20 enter a communicable range. Say The correction method is information that can identify the short distance communication device (the portable device 20 or the beacon) that is the reception destination of the current position information of the short distance communication processing unit 14. Therefore, the information set in the correction method (“passing” or “ "Beacon" corresponds to receiver information indicating a receiver, and also corresponds to device information indicating a device. The correction partner is information for specifying the short distance communication device which is the acquisition destination of the information to be updated. In the present embodiment, device identification information (device ID) is set.

  FIG. 5 is a diagram showing an example data configuration of priority information used in the present embodiment. The priority information is configured by setting the priority according to the correction method. The priority can also be said to be information indicating the reliability of the short distance communication device indicated by the correction method, as the reason will be described later. The priority information may be set in advance in the storage 4 or may be incorporated in an application that implements the correction unit 15 that uses the priority information.

  The components 11 to 16 in the mobile device 10 are realized by cooperative operation of a computer mounted on the mobile device 10 and a program operated by the CPU 1 mounted on the computer. Further, each of the storage units 17 to 19 is realized by the storage 4 mounted on the mobile device 10. Alternatively, the RAM 3 or an external storage means may be used via the network.

  Further, the program used in the present embodiment can be provided by communication means as well as provided by being stored in a computer readable recording medium such as a memory card. The programs provided from the communication means and the recording medium are installed in the computer, and various processes are realized by the CPU 1 of the computer sequentially executing the programs.

  Next, the operation in the present embodiment will be described. Since the portable devices 10 and 20 have the same configuration and perform the same operation, the portable device 10 will be described as a representative of the operation of the single portable device.

  First, regardless of whether or not the portable device 10 approaches another short distance communication device, a process of updating current position information is performed. This update processing will be described using the flowchart shown in FIG. Once started, this process is repeatedly executed until, for example, the user A moves one step until an end is instructed. In the present embodiment, it is assumed that the movement of one step of the user A is detected as the movement of the user A (mobile device 10). However, as described later, when using the elevator as the moving means, the portable device 10 moves without the user A moving, so assuming such a case, in the case of the user A moving Alternatively, steps 102 to 105 may be repeated periodically.

  The control unit 16 monitors the movement of the user A by constantly monitoring the measurement value from the acceleration sensor (N in step 101). Then, when the movement of the user A is detected (Y in step 101), the PDR calculation unit 11 detects the movement distance from the starting point (current position) based on the measurement value by the acceleration sensor according to the instruction from the control unit 16 The traveling direction from the starting point (the current position) is calculated based on the measured value by the sensor (step 102). Then, the PDR calculating unit 11 estimates a relative moving destination from the starting point (current position) based on the calculated moving distance and traveling direction (step 103), and stores it in the PDR data storage unit 17.

  Subsequently, the current position estimation unit 12 reads the current position information stored in the current condition information storage unit 19 and adds the relative moving destination estimated by the PDR calculation unit 11 with the current position information as the starting point. A new current position is estimated as A moves. Then, the current position estimation unit 12 updates the current position information stored in the current status information storage unit 19 with the current position information indicating the estimated current position (step 104).

  By the way, current position information obtained by estimation may include an error. That is, there is a possibility that the position of the user A may deviate from the actual position (current position). When the above-described process of estimating the current position is repeatedly performed, errors are accumulated in the estimated current position information. The error estimation unit 13 estimates an error of current position information obtained by this estimation. Specifically, the error of the current position information updated in step 103 is estimated, the error information (estimated error) stored in the current condition information storage unit 19 is read, and the estimated error is added to the read error information. Estimate a new error (accumulated error) associated with the movement of the user A. Then, the error estimation unit 13 updates the estimation error stored in the current information storage unit 19 with the estimated error (cumulative error) (step 105). A specific estimation method of the error of the current position information by the error estimation unit 13 will be described later. Here, the description will be continued on the assumption that numerical values can be obtained as illustrated in FIG. 4 as estimation errors.

  As described above, whenever the movement of the user A is detected, the estimation error of the current position information and the current position information of the portable device 10 (user A) held in the current state information storage unit 19 is updated. Become.

  Subsequently, correction of current position information will be described using the flowcharts shown in FIGS. 7A and 7B. Once started, the process is repeated until termination is instructed. As described above, as the short distance communication device, there are the mobile device 20 which moves and the beacon which does not move, but here, the mobile device 20 will be described as the short distance communication device unless otherwise specified. Of course, also in the portable device 20 as the short distance communication device, the processing described below with reference to FIGS. 7A and 7B as the mobile terminal is executed.

  The control unit 16 constantly monitors whether the portable device 20 is within the communication range of the short distance communication processing unit 14 (N in step 111). That the portable device 20 is within the communication range of the short-distance communication processing unit 14, that is, the control unit 16 can detect the portable device 20, the short-distance communication processing unit 14 performs short-distance wireless communication with the portable device 20. The portable device 10 and the portable device 20 are in close proximity to each other as much as possible. In the present embodiment, the proximity of the portable device 10 and the portable device 20 is assumed to be located at the same position, that is, the current position is the same. If the current positions are the same, the current positions indicated by the current position information of the portable devices 10 and 20 should be logically the same. However, as described above, in the present embodiment, the current position information includes an estimation error.

  When the portable device 20 is detected within the communication range of the short distance communication processing unit 14 (Y in step 111), the control unit 16 causes the short distance communication processing unit 14 to store the current information stored in the current status information storage unit 19. The position information and the estimation error are transmitted to the portable device 20 (step 112). At this time, the short distance communication processing unit 14 also transmits the device ID "Ta" of the own device as information for specifying the transmission source. Since the mobile device 20 operates in the same manner as the mobile device 10, the mobile device 20 transmits the current position information and the estimation error stored in the current information storage unit of the mobile device 20 to the mobile device 10. Thereby, the short distance communication processing unit 14 receives the current position information and the estimation error transmitted from the portable device 20 (step 113). The device ID “Tb” of the portable device 20 is added to the received information as information for specifying the transmission source. FIG. 1 schematically shows information exchange between the portable devices 10 and 20. In addition, transmission and reception of information may be implemented first.

  When the information exchange is completed, the correction unit 15 starts the operation in accordance with the instruction from the control unit 16. First, the correction unit 15 confirms the device ID of the transmission source of the information. Here, since the other party of communication is the mobile device 20, that is, the moving object (Y in step 114), the correction unit 15 reads the estimation error stored in the current information storage unit 19, and reads the estimation error and the error threshold (read Compare with the first threshold). The error threshold is a threshold for determining whether the value indicated by the estimation error is a credible value or not, and an appropriate value is preset according to the estimation method of the estimation error described later. As a result of comparison, if the read out estimation error exceeds the error threshold (N in step 115), the estimation error is estimated to be an unreliable value, and the process proceeds to step 118.

  On the other hand, if the read estimation error is less than the error threshold (N in step 115), the estimation error is estimated to be still a credible value. In this case, since the short distance communication processing unit 14 acquires the current position information by passing communication with the short distance communication device, here, the portable device 20 in step 113, the correction unit 15 has the priority shown in FIG. The priority information “0” corresponding to the correction method “passing” is acquired with reference to the degree information. Further, assuming that the present condition information shown in FIG. 4A is set in the present condition information storage unit 19, the correction unit 15 refers to the priority information and gives priority "1" corresponding to the correction method "beacon". It acquires (step 116).

  In this manner, the correction unit 15 corrects the priority (other party priority) corresponding to the correction method when the current position information is received from the short-distance communication device and the correction method currently set in the current state information storage unit 19 Is compared with the priority corresponding to (current priority), and when the other party's priority is equal to or higher than the current priority (Y in step 117), the process proceeds to step 118. On the other hand, if the other party's priority is lower than the current priority (N in step 117), the process returns to step 111.

  By the way, in the present embodiment, the priority corresponding to the correction method is also considered to be an index value indicating the reliability of the short distance communication device which is the acquisition destination of the current position information. As in the above example, it is assumed that the current position information of the beacon is more reliable and is the correct information between the current position information acquired by passing communication with the portable device 20 and the current position information of the fixedly installed beacon. Conceivable. Therefore, the priority of the “beacon” is set to “passing”, that is, higher than the portable device 20 as illustrated in FIG.

  The acquisition destination of the current position information when the current position information stored in the current state information storage unit 19 is corrected immediately before can be specified by the correction method set in the current state information storage unit 19. If the correction method indicates a beacon, the current position information currently set in the current state information storage unit 19 is considered to be more reliable information than the current position information acquired by passing communication with the portable device 20 at this time. Be Therefore, in step 113, the current position information from the portable device 20 having a lower reliability (priority) than the correction method (the current position information acquisition destination, in this example, "beacon" in this example) currently set in the current state information storage unit 19. It is not preferable to update the current status information storage unit 19 with the received current position information. Therefore, in the present embodiment, the process returns to step 111 without executing the correction process (step 120) of the current position information. Conversely, when current position information is received from a short distance communication device having a priority (reliability) corresponding to the correction method (current position information acquisition destination) currently set in the current state information storage unit 19, step Moving to 118, the present position information correction process can be performed by satisfying the other conditions.

  Even when the current position information currently set in the current state information storage unit 19 is corrected by the current position information acquired from the beacon, when a large amount of time has elapsed since the correction, the error of the current position is accumulated and estimated. The error may show a relatively large value. Therefore, when the elapsed time from the execution of the correction process based on the current position information obtained from the beacon becomes equal to or longer than the predetermined time and the estimation error becomes equal to or larger than the threshold, the processes shown in steps 116 and 117 are not performed. It is also good. This elapsed time can be obtained by calculating the difference between the correction time set in the current state information storage unit 19 and the current time.

  Further, in the present embodiment, mobile portable devices 10 and 20 and a fixedly installed beacon are described as an example of a short distance communication device. Therefore, FIG. 5 shows a setting example of priority information for two correction methods (acquisition destinations of current position information). However, it is not necessary to limit to this example. For example, among portable devices, there may be portable devices that move only a predetermined route in a facility by being carried by a security guard or the like. In this case, it is considered that the current position of the security officer's portable device can be estimated more correctly than the portable device of the user who moves in the facility indefinitely. As described above, even the short-distance communication devices of the same type may be classified into a plurality of correction methods and set in the priority information.

  Subsequently, the correction unit 15 compares the estimation error of the portable device 10 set in the current state information storage unit 19 and the estimation error of the portable device 20 received in step 113 with the above-described error threshold. Note that different error thresholds may be set for the own device and other devices. As described above, the error threshold is a threshold for determining whether or not the value indicated by the estimation error can be trusted, but when both estimation errors exceed the error threshold, that is, both estimation errors If it is determined that the value is an unreliable value (Y in step 118), the correction unit 15 subsequently determines the current position information of the portable device 10 set in the current information storage unit 19 and the portable device 20 received in step 113. The distance between the portable devices 10 and 20 is calculated based on the current position information of (step 122). Then, the correction unit 15 compares the calculated distance with the distance threshold.

  By the way, the portable device 10 and the portable device 20 should be in close proximity so as to exchange information (steps 111 to 113). Therefore, if the maximum distance that can be communicated between the portable devices 10 and 20 is set as the distance threshold, the distance calculated in step 122 should be equal to or less than the distance threshold. However, since the current position information includes the estimation error, there is a possibility that the distance calculated based on the current position information exceeds the distance threshold. This may occur when the current position indicated by the current position information of at least one of the mobile device 10 or the mobile device 20 is not correct. Therefore, there is a risk that the current position of the mobile device 10 (the current position information set in the current information storage unit 19) is updated with the current position of the mobile device 20 (the current position information received in step 113). In the present embodiment, when the calculated value of the distance exceeds the distance threshold (Y in step 123), the process returns to step 111 without executing the correction process of the current position information.

  On the other hand, if the calculated distance between the portable devices 10 and 20 is equal to or less than the distance threshold indicating the range in which the portable devices 10 and 20 can communicate, it proves that the portable device 10 and the portable device 20 approach each other. It will be done. By the way, the processing in step 123 is processing that is executed when the estimation errors of both the portable devices 10 and 20 exceed the error threshold in step 118. That is, it means that the current position of both the portable devices 10 and 20 may include an error as the error threshold is exceeded. Nevertheless, if the distance calculated based on the current position information in step 122 is equal to or less than the distance threshold value, it is considered that the current position information is correct and there is an error in the estimation error (accumulation error). Of course, the current positions of both the portable devices 10 and 20 are not correct and may not be coincident with each other by chance. However, since the estimation error is equal to or more than the error threshold, the possibility of coincidence is considered to be extremely small. That is, it is appropriate to infer that there is an error in the estimation error (accumulation error).

  Therefore, if the calculated distance is equal to or less than the distance threshold (N in step 123), the correction unit 15 resets the estimation error in the current information storage unit 19 to 0 (step 124). The processing described above is also performed in the mobile device 20, and the estimation error in the mobile device 20 is reset in the mobile device 20.

  Although the estimation error is described to be reset to 0 here, it is not necessary to set it to 0, and the estimation error may be corrected with a predetermined value close to 0 in consideration of the allowable range. Also, a predetermined value that is less than the error threshold and close to the error threshold may be set as the estimation error. Setting the estimation error to a value close to the error threshold means setting the current position of the own device (portable device 10) to an unreliable state. As a result, the current position information of the own device is easily updated by the current position information of the other device that can be trusted more than the own device (Y at step 115, N at step 118, Y at step 119, Y).

  On the other hand, when at least one of the estimation error of the own device set in the current state information storage unit 19 or the estimation error received in step 113 is less than the error threshold, that is, it is determined that at least one estimation error is a credible value. In the case (N in step 118), the correction unit 15 compares the estimation error of the portable device 10 read out from the current condition information storage unit 19 with the estimation error obtained from the portable device 20. Then, when the estimation error of the portable device 10 is larger than the estimation error obtained from the portable device 20 (Y in step 119), the correction unit 15 calculates the current position information and the estimation error stored in the current condition information storage unit 19 The current position information and the estimation error obtained from the portable device 20 are updated (step 120).

  If the estimation error of the portable device 10 is larger than the estimation error of the portable device 20, it is considered that the current position information in the portable device 20 indicates the current position relatively correctly. Although both may have estimation errors, it is considered that at least the current position of the portable device 20 on the communication partner side is correctly measured. Therefore, in the present embodiment, the information considered to be relatively correct is adopted, and the current position in the portable device 10 is corrected with the current position in the portable device 20 as described above.

  Here, since the information acquired from the portable device 20 is updated, the current position information and the estimation error after the correction shown in FIG. 4B are the same as those of the portable device 20. According to this numerical example, the estimation error in the portable device 10 is 30, which is larger than 15 of the estimation error in the portable device 20. Therefore, the correction unit 15 respectively corrects the current position information and the estimation error of the mobile device 10 with the current position information and the estimation error received from the mobile device 20. In addition, the correction unit 15 corrects the correction time by the passing communication by correcting the correction time with the corrected current time, and the correction method by “passing” by the passing communication; Update each one. As a result, the current position information and the estimation error in the portable device 10 are updated as shown in FIG. 4 (b). As described above, the current position information and the estimation error have the same values as those of the portable device 20.

  When the correction process in step 120 is completed, the process returns to step 111. Note that even if the portable device 20 is still in the communication range, the same update process may not be repeatedly performed since the above-described one correction may be performed for one detection. This can be determined by temporarily storing the device ID “Tb” received in step 113 until the portable device 20 is out of the communication range of the short distance communication processing unit 14.

  On the other hand, if the estimation error read out from the present condition information storage unit 19 is smaller than the estimation error obtained from the portable device 20 (N in step 119), the current position information stored in the present condition information storage unit 19 is the correct current position And returns to step 111 without updating the information. By the way, since the portable device 20 has the same function as the portable device 10, the portable device 20 receives the current position information and the estimation error transmitted by the portable device 10 in step 112, and uses the received information itself. The current position information and the estimation error stored in the current information storage unit in the device are updated.

  Furthermore, although the mobile device 20 is described as the communication partner here, even when the mobile device 10 approaches the beacon and the near-field wireless communication becomes possible with the beacon by the movement of the user A. is there. In this case (Y in step 111), unlike the mobile device 20, the beacon does not necessarily have the same function as the mobile devices 10 and 20. Thus, although the portable device 10 transmits the current position information and the estimation error (step 112), the beacon does not necessarily receive the transmitted information. Of course, there is no problem if you do not receive it.

  On the other hand, the short distance communication processing unit 14 receives the information transmitted from the beacon (step 113). The received information includes installation position information indicating the installation position of the beacon and a device ID of the beacon as information for specifying the transmission source.

  When it is determined that the communication partner is a beacon based on the device ID of the information transmission source (N in step 114), the correction unit 15 treats the received installation position information as current position information without comparing the estimation error described above, The current position information stored in the current state information storage unit 19 is updated, and the estimation error is initialized to 0 (step 121). Although it is considered that no estimation error is sent from the beacon, there is no need to compare the estimation errors since it is considered that there is no error in the installation position information received from the beacon (estimate error = 0) in the first place. In addition, since the correction unit 15 corrects the correction time with the corrected current time and the information acquired from the beacon, the correction unit 15 updates the correction method with the "beacon" and the correction partner with the device ID of the beacon of the information acquisition destination. .

  According to the present embodiment, even if the usage environment of the portable device 10 is an environment such as in a facility where it is difficult or impossible for GPS radio waves to reach, it is possible to correctly measure the current position as described above. .

  Here, a method of estimating the estimation error by the error estimation unit 13 will be described. In the present embodiment, an index such as a movement distance, an elapsed time, or the number of course changes is used.

  The movement distance is the movement distance of the user (mobile device), and can be measured based on the measurement value by the acceleration sensor. It is considered that the error of the current position information becomes relatively larger as the moving distance becomes longer. Basically, the movement distance indicates the movement distance after the estimation error stored in the current situation information storage unit 19 is initialized to zero. However, when corrected with the estimation error of the portable device 20, the estimation error obtained based on the moving distance is the movement of the user B after the estimation error stored in the current information storage unit of the portable device 20 is initialized. The estimation error accompanying the movement of the user A after correction is accumulated in the estimation error accompanying. Note that not the moving distance but an index of the number of steps of the user may be used. The number of steps can be measured by an acceleration sensor.

  The elapsed time is the elapsed time after the estimation error is initialized to 0, and can be measured by the clock means. Unless the user A moves at all, it is considered that the error of the current position information becomes relatively large as the time since being initialized passes. Basically, the elapsed time is an elapsed time after the estimation error stored in the current status information storage unit 19 is initialized to zero. However, when corrected with the estimation error of the portable device 20, the estimation error obtained based on the elapsed time is associated with the elapsed time since the estimation error stored in the current information storage unit of the portable device 20 is initialized. The estimation error associated with the elapsed time after the estimation error stored in the current condition information storage unit 19 of the portable device 10 is corrected is accumulated in the estimation error.

  The number of course changes is the number of times the user A changes the course by turning right or left in the facility, and can be measured by the acceleration sensor and the angular velocity sensor. As compared with the case where the user A keeps going straight, the error of the current position information is considered to be relatively large as the course change is repeated. Basically, the number of course changes is the number of course changes since the estimation error stored in the portable device 10 is initialized to zero. However, when corrected with the estimation error of the portable device 20, the estimation error obtained on the basis of the number of course changes is the user B after the estimation error stored in the current information storage unit of the portable device 20 is initialized. The estimation error accompanying the course change of the user A after correction is accumulated in the estimation error due to the course change. Instead of the number of course changes, an index may be used that is the sum (accumulated angle) of the angles (angles shifted from the straight ahead direction) when changing the course. The angle when the course is changed can be measured by the acceleration sensor and the gyro sensor.

  The moving distance, the elapsed time, and the number of course changes described above are numerical data, but in addition to this, for example, an index of moving means may be used to estimate the estimation error. The moving means is a moving means of the user, and walking, running, an elevator, stairs, a transport machine (vehicle, train, etc.), etc. can be considered. The moving means can be determined by analyzing measurement values of an acceleration sensor, an air pressure sensor, an angular velocity sensor, a three-axis magnetic sensor, and the like. For example, movement by walking is relatively slower than movement by traveling. In addition, the movement by the transport machine is relatively faster than the movement by traveling. It can be determined by setting a threshold in advance. The movement by the stairs is accompanied by the movement in the vertical direction in addition to the movement in the two-dimensional direction, and the movement by the elevator is only the movement in the vertical direction. Thus, the moving means can be estimated based on the measurement values of the various sensors 7.

  In addition, it is considered that walking is relatively less likely to cause an error associated with movement than traveling. Since the transport aircraft can be positioned using GPS instead of PDR, errors are considered to be relatively unlikely to occur. Under such a judgment, the estimation error is quantified for each estimated moving means so that it can be handled in the same manner as the moving distance and the like described above. In addition, the numerical value which shows an estimation difference | error is set to a small value as the movement means which an error does not produce easily.

  Furthermore, the error estimation unit 13 may use the information set in the device information storage unit 18 as an index for estimating the estimation error. For example, as the number of sensors used for positioning the current position increases, it is considered that the error of the current position information becomes relatively smaller. Further, when the model of the portable device 10 is new, the sensor mounted on the portable device 10 is also newer, and the newer the sensor is, the better the accuracy is, and it is considered that the error of the current position information becomes relatively small. As described above, by digitizing the number and accuracy of the sensors, they can be handled in the same manner as the moving distance and the like described above.

  As described above, the index described above can be used as information used to estimate the estimation error. These indices do not necessarily have to be used alone, and may be used in combination as appropriate. However, since the range and the magnitude of the numerical values that can be obtained differ depending on the index, and in order to give priority to each index, when calculating the estimation error by combining these index values, weighting is performed on each index to estimate the estimation error It is preferable to calculate In addition, when the other party of communication described above is a beacon, it is also necessary to calculate the estimation error to zero.

  As described above, the error estimating unit 13 calculates the estimation error of the current position information stored in the current condition information storage unit 19.

  As described above, in the present embodiment, the correction unit 15 is provided in the portable device 10, and the current position information and the estimation error stored in the current information storage unit 19 are corrected by itself. However, the pair of portable devices 10 and 20 that have conducted passing communication transmits the current position information and the estimation error to the management center (not shown) of the external portable device instead of the communication partner, and the current information storage unit The determination of necessity of correction of the stored current position information and the estimation error may be delegated to the management center.

1 CPU, 2 ROM, 3 RAM, 4 Storage, 5 Short Range Wireless Communication Interface (IF), 6 Liquid Crystal Panel, 7 Various Sensors, 8 Internal Bus, 10, 20 Mobile Device, 11 PDR Calculation Unit, 12 Current Position Estimation Unit , 13 error estimation unit, 14 short-range communication processing unit, 15 correction unit, 16 control unit, 17 PDR data storage unit, 18 device information storage unit, 19 current information storage unit.

Claims (7)

Storage means for storing current position information and error information;
The present position is estimated based on the present position information stored in the storage means and the measurement value by the mounted sensor, and the present position information stored in the storage means with the present position information indicating the estimated present position Current position estimation means for updating
Error estimation means for estimating an error of current position information stored in the storage means, and updating the error information stored in the storage means with error information indicating the estimated error;
A receiving unit that receives current position information and error information in the short-distance communication device from the short-distance communication device when the short-distance communication device approaches the device;
When at least one of the error information stored in the storage means and the error information received by the receiving means is less than or equal to a preset first threshold value, the error information stored in the storage means and the receiving means As a result of comparing with the received error information, when it is determined that the error of the current position information of the own terminal is larger than the error of the current position information of the short range communication device, the current position information and the error obtained from the short range communication device Correction means for executing a correction process for correcting the current position information and the error information stored in the storage means by updating the information;
I have a,
The correction means is a case where both the error information stored in the storage means and the error information received by the reception means exceed a preset first threshold, and the current stored in the storage means When the distance between the own terminal obtained from position information and the current position information received by the receiving unit and the near-field communication device is equal to or less than the distance for which the own terminal is considered to be close to the near-field communication device The mobile terminal , wherein the error information stored in is updated with a predetermined value less than the first threshold . The mobile terminal according to claim 1 , wherein the predetermined value is zero or a predetermined value close to zero.   The mobile terminal according to claim 1, wherein a value for determining whether or not the error of the current position information indicated by the error information can be trusted is set in the first threshold. The storage means further stores receiver information.
The correction means, when executing the correction process, updates the receiver information stored in the storage means with device information indicating a short distance communication device whose position is indicated by the current position information received by the reception means. The mobile terminal according to claim 1, characterized in that: The correction means executes the correction processing when the priority set corresponding to the receiver information stored in the storage means exceeds the priority set corresponding to the device information. The mobile terminal according to claim 4 , characterized in that: 6. The mobile terminal according to claim 5 , wherein the priority is set higher for the short distance communication device fixedly installed than the short distance communication device not fixedly installed. A mobile terminal carried by a user;
A near field communication device for performing near field communication with the mobile terminal;
Have
The mobile terminal is
Storage means for storing current position information and error information;
The present position is estimated based on the present position information stored in the storage means and the measurement value by the mounted sensor, and the present position information stored in the storage means with the present position information indicating the estimated present position Current position estimation means for updating
Error estimation means for estimating an error of current position information stored in the storage means, and updating the error information stored in the storage means with error information indicating the estimated error;
A receiving unit that receives current position information and error information in the short-distance communication device from the short-distance communication device when the short-distance communication device approaches the device;
When at least one of the error information stored in the storage means and the error information received by the receiving means is less than or equal to a preset first threshold value, the error information stored in the storage means and the receiving means As a result of comparing with the received error information, when it is determined that the error of the current position information of the own terminal is larger than the error of the current position information of the short range communication device, the current position information and the error obtained from the short range communication device Correction means for executing a correction process for correcting the current position information and the error information stored in the storage means by updating the information;
I have a,
The correction means is a case where both the error information stored in the storage means and the error information received by the reception means exceed a preset first threshold, and the current stored in the storage means When the distance between the own terminal obtained from position information and the current position information received by the receiving unit and the near-field communication device is equal to or less than the distance for which the own terminal is considered to be close to the near-field communication device The present position correction system is characterized in that the error information stored in is updated with a predetermined value less than the first threshold value .

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