JP5957906B2 - Detection apparatus, detection program, and detection method - Google Patents

Description

  The present invention relates to a detection device, a detection program, and a detection method.

  In recent years, there is an increasing demand for systems that measure pedestrian location information. As a method for measuring pedestrian location information, a method is generally used in which a portable positioning device held by a pedestrian is equipped with a satellite positioning device typified by GPS (Global Positioning System) to measure the location. Has been.

  However, the satellite positioning device cannot be used in an environment where radio waves from a GPS satellite such as indoors are obstructed. Therefore, it is considered that various sensors such as an acceleration sensor and a gyro sensor are mounted on a portable portable terminal, and the current position is identified by autonomous navigation from the acceleration detected by the acceleration sensor and the angular velocity detected by the gyro sensor. ing.

  In this autonomous navigation, the traveling direction is calculated by integrating the change in angular velocity detected by the gyro sensor. However, in the gyro sensor, an offset error may occur in the detected angular velocity, and when the gyro sensor is integrated including the offset error, a drift in which the traveling direction changes with time occurs, and the positioning accuracy deteriorates. Various techniques for suppressing such drift in the traveling direction have been proposed. For example, a technique has been proposed in which the angular velocity from the gyro sensor is smoothed, and the offset level of the gyro sensor is adaptively estimated and corrected using the smoothed average angular velocity. Also, for example, after turning on the power, the angular velocity of the angular velocity sensor is read once or a plurality of times to obtain an average value, and the average value is subtracted from the angular velocity sequentially output from the angular velocity sensor to correct the offset error. Technology has been proposed.

Japanese Patent Laid-Open No. 7-324941 JP-A-10-160506 JP-A-9-166438 JP 2004-340644 A

  However, the above prior art has a problem that the detection accuracy of the traveling direction may be lowered.

  When a pedestrian turns slowly, the turning angle per unit time is small. For this reason, in the prior art that corrects the offset level of the gyro sensor using the smoothed average angular velocity, the angular velocity output from the gyro sensor is small, so that the turning motion cannot be detected, and the detection accuracy of the traveling direction may be lowered. is there.

  Further, in the conventional technique for obtaining the average value of the angular velocity sensor and subtracting the average value from the angular velocity sequentially output from the angular velocity sensor, it is necessary to create a state where the attitude of the mobile terminal is stationary when obtaining the average value. However, the mobile terminal held by the pedestrian may not be stationary due to the walking motion of the pedestrian when calculating the average value, and the average value includes an angular velocity component due to the walking motion and generates an error. The detection accuracy of the traveling direction may be reduced.

  The disclosed technology has been made in view of the above, and an object thereof is to provide a detection device, a detection program, and a detection method capable of detecting a traveling direction while suppressing a decrease in detection accuracy.

  The detection device disclosed in the present application includes an angular velocity detection unit, a calculation unit, a determination unit, and an update unit. The angular velocity detection unit periodically detects the angular velocity of the moving body. The calculation unit calculates an integral value obtained by integrating the angular velocity detected by the angular velocity detection unit for each predetermined period required for the change in the traveling direction of the moving body. The determination unit determines whether the integral value calculated by the calculation unit is greater than a threshold value corresponding to an integral value of the offset error of the angular velocity in the predetermined period. An update part updates the advancing direction of the said mobile body based on the said integral value, when the said integral value determines with the said determination part being larger than the said threshold value.

  According to one aspect of the detection device disclosed in the present application, it is possible to detect a traveling direction while suppressing a decrease in detection accuracy.

FIG. 1 is a diagram illustrating the configuration of the detection apparatus according to the first embodiment. FIG. 2 is a diagram illustrating an example of a relationship between detected acceleration and angular velocity. FIG. 3 is a graph showing an example of the angular velocity detected by the gyro sensor when the pedestrian walks linearly. FIG. 4 is a graph showing an example of an ideal integrated value of angular velocity when a pedestrian walks linearly. FIG. 5 is a graph showing an example of the result of integrating the angular velocity detected by the gyro sensor when the pedestrian walks linearly. FIG. 6 is a diagram schematically showing matching between the shape of the path of the map and the shape of the link. FIG. 7 is a diagram illustrating an example of a result of autonomous navigation performed by the detection device according to the present embodiment. FIG. 8 is a diagram illustrating an example of a result of autonomous navigation performed by updating the traveling direction by the turning angle determined from the integral value. FIG. 9 is a flowchart illustrating the procedure of the traveling direction change detection process according to the first embodiment. FIG. 10 is a flowchart illustrating the procedure of link generation processing according to the first embodiment. FIG. 11 is a flowchart illustrating the procedure of the change process according to the first embodiment. FIG. 12 is a diagram illustrating the configuration of the detection device according to the second embodiment. FIG. 13 is a diagram illustrating an example of a result of integrating the horizontal component of the angular velocity during a period in which a person walks an even number of steps. FIG. 14 is a flowchart illustrating the procedure of the change process according to the second embodiment. FIG. 15 is a diagram illustrating the configuration of the detection device according to the third embodiment. FIG. 16 is a diagram illustrating an example of a passage. FIG. 17 is a flowchart illustrating the procedure of the change process according to the third embodiment. FIG. 18 is a diagram for describing an example of a computer that executes a detection program.

  Hereinafter, embodiments of a detection apparatus, a detection program, and a detection method disclosed in the present application will be described in detail with reference to the drawings. Note that this embodiment does not limit the disclosed technology. Each embodiment can be appropriately combined within a range in which processing contents are not contradictory.

[Configuration of detection device]
First, the configuration of the detection apparatus according to the present embodiment will be described. FIG. 1 is a diagram illustrating the configuration of the detection apparatus according to the first embodiment. A detection device 10 shown in FIG. 1 is a device that is equipped with various sensors and detects a position from detection results of the various sensors. For example, a portable device such as a computer, a mobile phone, a smartphone, or a PDA (Personal Digital Assistants). Terminal. The detection apparatus 10 is carried by a moving body and moves together, and the current position is specified by autonomous navigation from the detected position. An example of the moving body is a pedestrian.

  As illustrated in FIG. 1, the detection device 10 includes a gyro sensor 11, an acceleration sensor 12, and a pedometer 13 as various sensors. Moreover, the detection apparatus 10 has the memory | storage part 20 which memorize | stores various information, and the control part 30 which calculates a position from the detection result by various sensors. In the example of FIG. 1, the case where the detection device 10 includes three sensors is illustrated. However, if at least the gyro sensor 11 is mounted, a change in the traveling direction of the moving body is detected as described later. be able to. The detection device 10 may further include a sensor other than these, for example, a geomagnetic sensor.

  The gyro sensor 11 is a sensor that detects angular velocity. As one aspect, the gyro sensor 11 outputs a signal indicating the detected angular velocity to the control unit 30 every time it detects the angular velocity. As a method for measuring the angular velocity, any method such as an oscillation method, an optical method, a rotation method, and a fluid method can be adopted. In the following description, it is assumed that a vibration type gyro sensor formed into a chip using MEMS (Micro Electro Mechanical Systems) technology is used, but a gyro sensor having another configuration may be used.

  The acceleration sensor 12 is a sensor that detects acceleration. As one aspect, the acceleration sensor 12 outputs a signal indicating the detected acceleration to the control unit 30 every time it detects the acceleration. As an acceleration measuring method, any method such as a semiconductor method, a mechanical method, an optical method, or the like can be adopted.

  The pedometer 13 is a sensor that measures the number of steps of a pedestrian. As one aspect, the pedometer 13 counts up the number of steps each time a pedestrian's walk is detected, and outputs step number information indicating the measured number of steps to the control unit 30. As a method for measuring the number of steps, an arbitrary method such as a pendulum method or an acceleration sensor method can be adopted. Note that the number of steps may be measured using the acceleration sensor 12.

  The storage unit 20 is a storage device that stores various data. As an aspect of the storage unit 20, a storage device such as a hard disk or an optical disk can be employed in addition to a semiconductor memory that can rewrite data such as a flash memory and a non-volatile static random access memory (NVSRAM).

  For example, the memory | storage part 20 memorize | stores the map information 21 of the movement range to which a moving body moves. Such map information 21 may be registered in the storage unit 20 in advance. Further, the map information 21 may be appropriately acquired from a server of a trader that provides a service that provides map information.

  The control unit 30 has an internal memory for storing programs defining various processing procedures and control data, and executes various processes using these. As shown in FIG. 1, the control unit 30 includes a calculation unit 31, a change unit 32, a determination unit 33, an update unit 34, a distance derivation unit 35, a link generation unit 36, a matching unit 37, An information detection unit 38 and a position deriving unit 39 are included.

  The calculation unit 31 is a processing unit that calculates an integral value obtained by integrating the angular velocities detected by the gyro sensor 11. As one aspect, the calculation unit 31 calculates an integral value obtained by integrating the horizontal component of the angular velocity detected by the gyro sensor 11 for each predetermined period. This predetermined period is a period required for a change in the traveling direction of the moving body. The predetermined period may be a fixed value or may be changed according to the speed of the moving object carrying the detection device 10. In the present embodiment, a case where the predetermined period is changed by the changing unit 32 described later will be described. When the predetermined period is a fixed value, for example, in order to change the traveling direction of the majority of people by measuring the period required for changing the traveling direction when the person is moving, for example, Set to include the required period.

  For example, the acceleration sensor 12 is a three-axis acceleration sensor that detects acceleration in the x-axis direction, y-axis direction, and z-axis direction, and the gyro sensor 11 is a three-axis angular velocity sensor that detects angular velocities in the x-axis, y-axis, and z-axis. A case will be described. FIG. 2 is a diagram illustrating an example of a relationship between detected acceleration and angular velocity. In this case, the calculation unit 31 calculates the time integral value (Δθx, Δθy, Δθz) of each axis obtained by integrating the angular velocity (ω = (ωx, ωy, ωz)) from the time t for a predetermined period (Δt), using the following formula (1 ).

  Further, the calculation unit 31 uses the acceleration (a = (ax, ay, az)) detected by the acceleration sensor 12 to calculate the attitude (θy, θz) of the terminal from the following equation (2).

  The calculation unit 31 uses the time integral value (Δθx, Δθy, Δθz) of each axis of the gyro sensor obtained by the above equation (1) and the terminal posture (θy, θz) obtained by the above equation (2). The horizontal component (Δθ) of the azimuth change amount is calculated from the following equation (3).

  Here, Rx (θ), Ry (θ), and Rz (θ) are rotation matrices that represent θ rotation around the x, y, and z axes, respectively, and u is an arbitrary unit vector that represents a terminal. .

  The changing unit 32 is a processing unit that changes a predetermined period (Δt) in which the calculating unit 31 integrates the angular velocity. As one aspect, the changing unit 32 obtains the moving speed of the moving body based on the acceleration detected by the acceleration sensor 12. And the change part 32 changes a predetermined period according to the moving speed of a moving body.

  Here, when a person changes the direction of travel at a corner of a passage, etc., the time required to change the direction of travel from the beginning to the end of the turn at the corner is higher when the movement speed is faster than when the movement speed is slow. short. Therefore, the changing unit 32 shortens the predetermined period when the moving speed of the moving body is fast, and lengthens the predetermined period when the moving speed of the moving body is slow. That is, since the time required for bending changes depending on the walking speed, the changing unit 32 changes the predetermined period according to the walking speed. For example, the changing unit 32 changes the predetermined period in proportion to the moving speed of the moving body. As a result, an integral value of the angular velocity in the period in which the traveling direction is changed can be obtained. The moving speed may be estimated from the amplitude of the acceleration sensor 12 during walking, or may be estimated from pedestrian personal data (age, sex, past walking speed history).

  Here, the angular velocity detected by the gyro sensor 11 when a pedestrian carries the detection device 10 will be described. FIG. 3 is a graph showing an example of the angular velocity detected by the gyro sensor when the pedestrian walks linearly. As shown in FIG. 3, even when a pedestrian walks linearly, a change in angular velocity is detected. This is because when the person walks, the right foot and the left foot are alternately moved, and thus the body rotates left and right during walking even when walking linearly without changing the traveling direction. When a pedestrian walks linearly, the left and right rotation angles due to human walking are substantially the same. For this reason, the integrated value of the angular velocity detected by the gyro sensor 11 should be substantially constant when the pedestrian walks linearly. FIG. 4 is a graph showing an example of an ideal integrated value of angular velocity when a pedestrian walks linearly. In the example of FIG. 4, since the offset error does not occur in the angular velocity detected by the gyro sensor 11, the width of the change in the integrated value is small.

  However, the gyro sensor 11 may cause an offset error in the detected angular velocity. For this reason, the integrated value obtained by integrating the angular velocity by the calculation unit 31 includes an offset error. FIG. 5 is a graph showing an example of the result of integrating the angular velocity detected by the gyro sensor when the pedestrian walks linearly. As shown in FIG. 5, the integral value of the angular velocity increases with time in one direction due to the influence of the accumulated offset error. Due to this influence, a drift occurs in which the traveling direction changes with time.

  By the way, when a person walks in a passage or the like, the person turns at an intersection or a corner to change the traveling direction. In other words, the direction of travel of a person changes only during a turning operation, and the direction of travel is almost constant since the pedestrian is traveling straight at other times.

  Therefore, the determination unit 33 determines whether or not there has been a turning motion based on an integral value obtained by integrating the angular velocities calculated by the calculation unit 31. As one aspect, the determination unit 33 determines whether the calculated integral value is greater than a predetermined threshold value. This threshold value is set to a value corresponding to the integral value of the offset error of the angular velocity in a predetermined period. This threshold value may be a fixed value or may be changed according to a predetermined period, a moving speed, or the like. The threshold may be a fixed value when the predetermined period is a fixed value. In this embodiment, the threshold value is changed according to a change in a predetermined period. For example, when the changing unit 32 changes the predetermined period, the determination unit 33 performs the determination by changing the threshold in proportion to the predetermined period.

  The update unit 34 updates the traveling direction of the moving object. As one aspect, when the determining unit 33 determines that the integrated value is larger than the threshold value, the updating unit 34 updates the traveling direction of the moving body based on the integrated value. That is, when the integrated value is larger than the threshold value, the updating unit 34 updates the traveling direction by the turning angle determined from the integrated value, assuming that the turning operation has been performed. Further, when the integrated value is equal to or less than the threshold value, the updating unit 34 assumes that the operation is a straight traveling operation, and fixes the traveling direction without updating the traveling direction so far.

  The distance deriving unit 35 derives the moving distance of the moving body. As one aspect, the distance deriving unit 35 derives the moving distance by multiplying the step count indicated by the step count information input from the pedometer 13 as needed. The stride may be a fixed value, may be directly specified by the user, or may be estimated from pedestrian personal data (age, height, sex, past walking speed history). As an example, in the method of calculating the stride from the height, a value obtained by subtracting a predetermined value from the height may be used as the stride, or a value obtained by multiplying the height by a predetermined coefficient may be used as the stride. For example, “height −100 cm” may be used as the stride, and “height × 0.37” may be used as the stride. The distance deriving unit 35 may derive the moving distance from the acceleration detected by the acceleration sensor 12 instead of the number of steps. For example, the distance deriving unit 35 derives the movement distance by integrating the acceleration detected by the acceleration sensor 12 twice.

  The link generation unit 36 generates a link indicating a trajectory that the moving body has moved. As one aspect, at the timing when the traveling direction is updated by the updating unit 34, the link generation unit 36 changes the traveling direction at the moving distance derived by the distance deriving unit 35 by the turning angle and the moving body moves. A link indicating a trajectory is generated. For example, the link generation unit 36 updates the travel direction (θ) updated by the update unit 34, the travel distance (l) after updating the travel direction derived by the distance deriving unit 35, and the travel direction at the time of update. Coordinates (xp, yp) are calculated from the following equation (4) using the movement distance (lp).

  And the link production | generation part 36 adds the advancing direction to the coordinate of the terminal at the time of an update at the calculated coordinate (xp, yp), and makes it a new link.

  The matching unit 37 performs map matching with the map generated by the link generated by the link generation unit 36 and the map information 21. As an aspect, the matching unit 37 moves the position of the link generated by the link generation unit 36 with respect to the map, and rotates the link one turn at a predetermined angle at each position, so that the shape of the map passage and the link Are compared, and the position where the shape is most similar is specified. FIG. 6 is a diagram schematically showing matching between the shape of the path of the map and the shape of the link. For example, the matching unit 37 obtains the similarity by matching the shape of the map passage and the shape of the link, and specifies the position having the highest similarity. In order to make it easier to find a route having a similar shape, it is possible to roughly detect the current position based on mobile communication base station information such as a mobile phone and to limit the roads to be compared. In addition to map matching, the position may be detected by other positioning techniques such as providing position information using mobile communication base station information or wireless LAN, or the user may manually specify the position. .

  The initial information detection unit 38 detects an initial position and an initial direction at which the moving body starts moving. As an aspect, the initial information detection unit 38 detects an initial position and an initial direction at which the moving body starts moving based on the matching result by the matching unit 37. For example, the initial information detection unit 38 moves the coordinates of the starting point at which the moving body indicated by the link starts moving when the link is arranged at the position having the highest similarity to the map indicated by the map information 21. Is identified as the initial position where the operation is started. In addition, the initial information detection unit 38 specifies an initial azimuth in which the moving body starts moving from a rotation angle obtained by rotating the link in order to place the link at a position having the highest similarity to the map. The user may manually specify an initial position and an initial direction at which the moving body starts moving from an operation unit (not shown).

  The position deriving unit 39 identifies the current position of the moving body and outputs position information indicating the identified position. As one mode, the position deriving unit 39 assumes that the moving track indicated by the link generated by the link generating unit 36 has been moved from the initial position and initial orientation detected by the initial information detecting unit 38 and the current position of the moving object. A position is specified, and position information indicating the specified position is output.

  Note that various integrated circuits and electronic circuits can be employed for the control unit 30. For example, an ASIC (Application Specific Integrated Circuit) is an example of the integrated circuit. Examples of the electronic circuit include a central processing unit (CPU) and a micro processing unit (MPU).

  FIG. 7 is a diagram illustrating an example of a result of autonomous navigation performed by the detection device according to the present embodiment. As shown in FIG. 7, the detection apparatus 10 according to the present embodiment can accurately estimate the route on which the pedestrian walks by autonomous navigation.

  On the other hand, when the integral value is larger than the threshold value as in this embodiment, the turning operation is not performed, for example, when the navigation direction is updated by the turning angle determined from the integral value and autonomous navigation is performed. A drift occurs in which the traveling direction changes with time. FIG. 8 is a diagram illustrating an example of a result of autonomous navigation performed by updating the traveling direction by the turning angle determined from the integral value. As shown in FIG. 8, a drift in which the traveling direction changes occurs, and the route that the pedestrian walks cannot be estimated.

  Thus, according to the detection apparatus 10 according to the present embodiment, the horizontal component of the angular velocity detected by the gyro sensor 11 is integrated for each predetermined period, and when the integrated value is larger than the threshold value, the turning operation is performed. As a result, the current position can be estimated with high accuracy. Further, according to the detection device 10 according to the present embodiment, even when the pedestrian turns slowly and the angular velocity is small, the angular velocity corresponding to the turning motion is integrated by integrating for a predetermined period, so that the turning motion can be detected. In addition, according to the detection device 10 according to the present embodiment, the current position can be estimated with high accuracy without creating a state where the posture of the detection device 10 is stationary.

  Next, the flow of various processes executed when performing autonomous navigation by the detection apparatus 10 according to the present embodiment will be described. Initially, the flow of the advancing direction change detection process which detects the change of the advancing direction of a moving body by the detection apparatus 10 which concerns on a present Example is demonstrated. FIG. 9 is a flowchart illustrating the procedure of the traveling direction change detection process according to the first embodiment. This advancing direction change detection process is activated when a predetermined operation for instructing the detection device 10 to start autonomous navigation is performed.

  As shown in FIG. 9, the calculation unit 31 initializes a timer T to zero and starts measuring time (step S10). And the calculation part 31 determines whether the timer T passed the predetermined period (step S11). When the timer T has not passed the predetermined period (No at Step S11), the calculation unit 31 calculates the horizontal component of the angular velocity detected by the gyro sensor 11, and integrates the horizontal component of the angular velocity in the predetermined period ( Step S12), the process proceeds to step S11 again. When the timer T has passed the predetermined period (Yes at Step S11), the determination unit 33 determines whether or not the calculated integral value is greater than a predetermined threshold (Step S13). If the integral value is less than or equal to the threshold (No at Step S13), the process proceeds to Step S10.

  On the other hand, when the integral value is larger than the threshold value (Yes at Step S13), the updating unit 34 updates the traveling direction of the moving body based on the integral value (Step S14). The update unit 34 determines whether a predetermined operation for instructing the end of the process has been performed (step S15). If a predetermined operation for instructing the end of the process is performed (Yes at step S15), the process ends. On the other hand, when the predetermined operation for instructing the end of the process has not been performed (No at Step S15), the process proceeds to Step S10.

  Next, a flow of link generation processing for generating a link indicating a trajectory where the moving body has moved by the detection apparatus 10 according to the present embodiment will be described. FIG. 10 is a flowchart illustrating the procedure of link generation processing according to the first embodiment. This link generation process is activated when a predetermined operation for instructing the detection device 10 to start autonomous navigation is performed.

  As illustrated in FIG. 10, the link generation unit 36 determines whether the moving body has moved based on the change in the movement distance derived by the distance deriving unit 35 (step S20). When the moving body is not moving (No at Step S20), the process proceeds to Step S20 and waits for movement. When the moving body has moved (Yes at Step S20), the link generation unit 36 reads the moving direction of the moving body obtained by the update unit 34 (Step S21). The link generation unit 36 generates a link indicating a trajectory that the moving body has moved by the amount of change in the movement distance derived by the distance deriving unit 35 in the read movement direction (step S22). The link generator 36 determines whether or not a predetermined operation for instructing the end of the process has been performed (step S23). If a predetermined operation for instructing the end of the process is performed (Yes at step S23), the process ends. On the other hand, when the predetermined operation for instructing the end of the process is not performed (No at Step S23), the process proceeds to Step S20.

  Next, the flow of change processing for changing the predetermined period for integrating the angular velocity by the detection apparatus 10 according to the present embodiment will be described. FIG. 11 is a flowchart illustrating the procedure of the change process according to the first embodiment. This change process is started when a predetermined operation for instructing the detection device 10 to start autonomous navigation is performed.

  As shown in FIG. 11, the changing unit 32 obtains the moving speed of the moving body based on the acceleration detected by the acceleration sensor 12 (step S30). The changing unit 32 determines whether or not the moving speed has changed (step S31). If the moving speed has not changed (No at Step S31), the process proceeds to Step S30. When the moving speed changes (Yes at Step S31), the changing unit 32 changes the predetermined period according to the moving speed of the moving body (Step S32). Then, the changing unit 32 determines whether or not a predetermined operation for instructing the end of the process has been performed (step S33). If a predetermined operation for instructing the end of the process is performed (Yes at step S33), the process ends. On the other hand, when the predetermined operation for instructing the end of the process has not been performed (No at Step S33), the process proceeds to Step S30.

  As described above, the detection apparatus 10 according to the present embodiment periodically detects the angular velocity of the moving body. And the detection apparatus 10 which concerns on a present Example calculates the integral value which integrated the detected angular velocity for every predetermined period required for the change of the advancing direction of a moving body. The detection apparatus 10 according to the present embodiment determines whether or not the calculated integral value is larger than a threshold value corresponding to the integral value of the angular velocity offset error in a predetermined period. When it is determined that the integral value is larger than the threshold value, the detection apparatus 10 according to the present embodiment updates the traveling direction of the moving body based on the integral value. Thereby, according to the detection apparatus 10 which concerns on a present Example, the advancing direction can be detected suppressing the fall of detection accuracy.

  Moreover, the detection apparatus 10 according to the present embodiment detects the acceleration of the moving body. And the detection apparatus 10 which concerns on a present Example calculates | requires an attitude | position using the detected acceleration, and integrates the horizontal component of angular velocity. Thereby, according to the detection apparatus 10 which concerns on a present Example, the change of the advancing direction is accurately detectable.

  In addition, the detection apparatus 10 according to the present embodiment detects the moving speed of the moving body, and when the detected moving speed of the moving body is fast, the predetermined period is short, and when the moving speed of the moving body is slow, the predetermined period. Change the length longer. Thereby, according to the detection apparatus 10 according to the present embodiment, even when the moving speed of the moving body changes, an integral value obtained by integrating the angular velocity for the time required for changing the traveling direction can be obtained. Changes in the direction of travel can be detected with high accuracy.

  Next, Example 2 will be described. In the second embodiment, a case where the number of steps that a person walks as a moving body is measured and the predetermined period is changed to a period in which the measured number of steps is an even number will be described. FIG. 12 is a diagram illustrating the configuration of the detection device according to the second embodiment. In addition, the same code | symbol is attached | subjected about the part same as the detection apparatus which concerns on Example 1 shown in FIG. 1, and a different part is demonstrated.

  The change unit 32 receives step count information from the pedometer 13 as needed. The changing unit 32 is a processing unit that changes a predetermined period during which the calculating unit 31 integrates the angular velocity based on the step count information. As one aspect, the changing unit 32 changes the predetermined period in a period in which the measured number of steps is an even number. For example, the changing unit 32 counts the number of steps based on the number of steps information, and changes the predetermined period to a period in which the measured number of steps is a predetermined even number.

  Here, when a person walks, the right and left feet are alternately moved, so even if the person walks linearly without changing the direction of travel, the body rotates left and right during walking. The angles are substantially the same. For this reason, the predetermined period is changed to the period in which the number of steps is an even number, and the horizontal component of the angular velocity detected by the gyro sensor 11 is calculated for the period in which the number of steps is an even number. It is possible to cancel the angular velocity component that rotates in a straight line. Thereby, the angular velocity resulting from changing the traveling direction can be integrated.

  FIG. 13 is a diagram illustrating an example of a result of integrating the horizontal component of the angular velocity during a period in which a person walks an even number of steps. The example of FIG. 13 is the result of integrating the horizontal component of the angular velocity during the period of walking for 14 steps. P1 to P4 portions change the traveling direction. The other parts walk linearly. As shown in FIG. 13, the integral value obtained by integrating the horizontal component of the angular velocity is a large value in the P1 to P4 portions, and is a small value in other linearly walking portions. Therefore, by integrating the horizontal component of the angular velocity during a period in which the number of steps is an even number, it is possible to accurately detect a change in the traveling direction.

  FIG. 14 is a flowchart illustrating the procedure of the change process according to the second embodiment. In addition, about the part same as the change process which concerns on Example 1 shown in FIG. 11, the same code | symbol is attached | subjected and a different part is demonstrated.

  As shown in FIG. 14, when the moving speed changes (Yes at Step S31), the changing unit 32 obtains a walking period in which a predetermined number of steps are evenly walked based on the number of steps information (Step S34). And the change part 32 changes a predetermined period to a walk period (step S35), and transfers to step S33.

  As described above, the detection apparatus 10 according to the present embodiment measures the number of steps that a person walks as a moving body, and changes the predetermined period to a period in which the measured number of steps is an even number. Thereby, according to the detection apparatus 10 according to the present embodiment, the angular velocity is integrated only during a period in which the number of steps is an even number, and the angular velocity component in which the body rotates to the left and right during walking is canceled. Can be detected with high accuracy.

  Next, Example 3 will be described. In the third embodiment, a case will be described in which the passage width at the corner of the passage through which the mobile body passes next is specified, and the predetermined period is changed longer according to the passage width. FIG. 15 is a diagram illustrating the configuration of the detection device according to the third embodiment. In addition, the same code | symbol is attached | subjected about the part same as the detection apparatus which concerns on Example 1 shown in FIG. 1, and a different part is demonstrated.

  As illustrated in FIG. 15, the control unit 30 further includes a specifying unit 40. Based on the position specified by the position deriving unit 39 and the map information 21 stored in the storage unit 20, the specifying unit 40 specifies the passage width at the corner of the passage through which the mobile body passes next.

  The changing unit 32 changes the predetermined period longer according to the passage width specified by the specifying unit 40.

  Here, when a person changes the traveling direction based on the corner of the passage, the time required to change the traveling direction from the beginning to the end of the corner is longer when the passage width is wider than when the passage width is narrow. Therefore, as one aspect, the changing unit 32 shortens the predetermined period when the passage width is narrow, and lengthens the predetermined period when the passage width is wide. For example, the changing unit 32 obtains the required turning distance necessary for turning from the shape of the passage. As an example, the changing unit 32 obtains the required turning distance from the elliptic integral using the road width and the turn angle at the next turn. FIG. 16 is a diagram illustrating an example of a passage. Assuming a bend where the passages of widths w1 and w2 intersect at an angle θc as shown in FIG. 16, the length r ′ of the major axis is obtained from the following equation (5).

  Then, the changing unit 32 obtains a quarter circumference Ic of the ellipse whose major axis is r 'and whose minor axis is w1 as the required turning distance. Then, the changing unit 32 calculates the required turn time by dividing the circumference Ic by the moving speed, and sets the required turn time as a predetermined period. In this way, by predicting the required turn time at the corner of the path through which the mobile body passes next and integrating the horizontal component of the angular velocity for the required turn time, it is possible to accurately detect the change in the traveling direction.

  FIG. 17 is a flowchart illustrating the procedure of the change process according to the third embodiment.

  As shown in FIG. 17, the changing unit 32 obtains the moving speed of the moving body based on the acceleration detected by the acceleration sensor 12 (step S50). The specifying unit 40 specifies the passage width at the corner of the passage that passes next (step S51). The changing unit 32 obtains the required turning distance at the corner of the passage that passes next, and obtains the required turning time by dividing the required turning distance by the moving speed (step S52). Then, the changing unit 32 changes the predetermined period to the required turn time (step S53). The changing unit 32 determines whether or not a predetermined operation for instructing the end of the process has been performed (step S54). If a predetermined operation for instructing the end of the process is performed (Yes at step S54), the process ends. On the other hand, when the predetermined operation for instructing the end of the process has not been performed (No at Step S54), the process proceeds to Step S50.

  As described above, the detection device 10 according to the present embodiment specifies the path width of the corner of the path through which the moving body passes next, and shortens the predetermined period when the specified path width is narrow, If the passage width is wide, the predetermined period is changed longer. Thereby, according to the detection apparatus 10 according to the present embodiment, an integral value obtained by integrating the angular velocity for the time required for changing the traveling direction at the corner of the path through which the moving body passes next can be obtained. It is possible to accurately detect a change in the direction of travel.

  Although the embodiments related to the disclosed apparatus have been described above, the present invention may be implemented in various different forms other than the above-described embodiments. Therefore, another embodiment included in the present invention will be described below.

  For example, in the first to third embodiments, the case where the predetermined period for integrating the angular velocity is changed according to the moving speed, the period of even steps, and the path width of the corner of the path that passes next is disclosed. However, the apparatus is not limited to this. The predetermined period may be determined by combining them. For example, the faster the moving speed is, the shorter the predetermined period is. However, the predetermined period may be changed to a longer period when the predetermined period is an even number of steps or when the passage width at the corner of the next passage is large.

  Further, each component of each illustrated apparatus is functionally conceptual, and does not necessarily need to be physically configured as illustrated. In other words, the specific state of distribution / integration of each device is not limited to the one shown in the figure, and all or a part thereof may be functionally or physically distributed or arbitrarily distributed in arbitrary units according to various loads or usage conditions. Can be integrated and configured. For example, the calculation unit 31, the change unit 32, the determination unit 33, the update unit 34, the distance derivation unit 35, the link generation unit 36, the matching unit 37, the initial information detection unit 38, the position derivation unit 39, and the identification unit 40 of the control unit 30. These processing units may be integrated as appropriate. Further, the processing of each processing unit may be appropriately separated into a plurality of processing units. Further, all or any part of each processing function performed in each processing unit can be realized by a CPU and a program analyzed and executed by the CPU, or can be realized as hardware by wired logic. .

[Detection program]
The various processes described in the above embodiments can be realized by executing a prepared program on a computer such as a personal computer or a workstation. Therefore, in the following, an example of a computer that executes a detection program having the same function as in the above embodiment and detects the current position by autonomous navigation will be described with reference to FIG.

  FIG. 18 is a diagram for describing an example of a computer that executes a detection program. As illustrated in FIG. 18, the computer 100 includes an operation unit 110a, a gyro sensor 110b, an acceleration sensor 110c, a pedometer 110d, a display 120, and a communication unit 130. Further, the computer 100 includes a CPU 150, a ROM 160, an HDD 170, and a RAM 180. These units 110 to 180 are connected via a bus 140.

  The HDD 170 stores in advance a detection program 170a that performs the same function as each processing unit of the control unit 30. The detection program 170a may be appropriately integrated or separated as in the case of each component shown in the first embodiment. In other words, all data stored in the HDD 170 need not always be stored in the HDD 170, and only data necessary for processing may be stored in the HDD 170.

  Then, the CPU 150 reads the detection program 170 a from the HDD 170 and expands it in the RAM 180. Thereby, as shown in FIG. 18, the detection program 170a functions as a detection process 180a. The detection process 180a expands various data read from the HDD 170 in an area allocated to itself on the RAM 180 as appropriate, and executes various processes based on the expanded data. Note that the detection process 180a includes processing executed by each processing unit of the control unit 30, for example, processing shown in FIGS. 9 to 11, FIG. 14, and FIG. In addition, each processing unit virtually realized on the CPU 150 does not always require that all processing units operate on the CPU 150, and only a processing unit necessary for the processing needs to be virtually realized.

  Note that the above-described detection program 170a is not necessarily stored in the HDD 170 or the ROM 160 from the beginning. For example, each program is stored in a “portable physical medium” such as a flexible disk inserted into the computer 100, so-called FD, CD-ROM, DVD disk, magneto-optical disk, or IC card. Then, the computer 100 may acquire and execute each program from these portable physical media. Each program is stored in another computer or server device connected to the computer 100 via a public line, the Internet, a LAN, a WAN, etc., and the computer 100 acquires and executes each program from these. It may be.

DESCRIPTION OF SYMBOLS 10 Detection apparatus 11 Gyro sensor 12 Acceleration sensor 13 Pedometer 30 Control part 31 Calculation part 32 Change part 33 Determination part 34 Update part 35 Distance derivation part 36 Link generation part 37 Matching part 38 Initial information detection part 39 Position derivation part 40 Identification part

Claims (6)

An angular velocity detector that periodically detects the angular velocity of the pedestrian,
A speed detector for detecting the moving speed of the pedestrian;
A change in which a predetermined period corresponding to a plurality of steps of the pedestrian is changed when the moving speed of the pedestrian detected by the speed detection unit is fast and long when the moving speed of the pedestrian is slow. And
A calculation unit for calculating an integral value obtained by integrating the angular velocity detected by the angular velocity detection unit with the predetermined period changed by the changing unit ;
A determination unit that determines whether an integral value calculated by the calculation unit is greater than a threshold corresponding to an integral value of the offset error of the angular velocity in the predetermined period;
When the determination unit determines that the integrated value is greater than the threshold, an update unit that updates the pedestrian's traveling direction based on the integrated value;
A detection apparatus comprising: An acceleration detection unit for detecting the acceleration of the pedestrian;
The detection device according to claim 1, wherein the calculation unit obtains an attitude using the acceleration detected by the acceleration detection unit, and integrates a horizontal component of the angular velocity detected by the angular velocity detection unit. . And further comprising a specifying part for specifying a passage width at a corner of a passage through which the pedestrian passes next,
The changing unit, when the passage width specified by the specifying unit is narrow short predetermined period, if the channel width is wide claim 1 or 2, characterized in that changing longer the predetermined period Detection device. A measuring unit that measures the number of steps the pedestrian walks;
The detection device according to any one of claims 1 to 3 , wherein the changing unit changes the predetermined period during a period in which the number of steps measured by the measuring unit is an even number. On the computer,
During a predetermined period corresponding to the pedestrian moving a plurality of steps, when the moving speed of the pedestrian detected by the speed detecting unit that detects the moving speed of the pedestrian is high, the moving speed of the pedestrian is short. If slow, change it longer,
The angular velocity detected by the angular velocity detection unit for detecting an angular velocity of the pedestrian periodically calculates a modified said predetermined period integrating the integral value,
Determining whether the calculated integral value is greater than a threshold value corresponding to the integral value of the offset error of the angular velocity in the predetermined period;
When it determines with the said integrated value being larger than the said threshold value, the detection program characterized by performing each process which updates the advancing direction of the said pedestrian based on the said integrated value. Computer
During a predetermined period corresponding to the pedestrian moving a plurality of steps, when the moving speed of the pedestrian detected by the speed detecting unit that detects the moving speed of the pedestrian is high, the moving speed of the pedestrian is short. If slow, change it longer,
The angular velocity detected by the angular velocity detection unit for detecting an angular velocity of the pedestrian periodically calculates a modified said predetermined period integrating the integral value,
Determining whether the calculated integral value is greater than a threshold value corresponding to the integral value of the offset error of the angular velocity in the predetermined period;
When it determines with the said integrated value being larger than the said threshold value, each process which updates the advancing direction of the said pedestrian based on the said integrated value is performed, The detection method characterized by the above-mentioned.

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