JP5098919B2 - Moving direction calculating device, moving direction calculating program, and moving direction calculating method - Google Patents

Description

  The present invention relates to a movement direction calculation device, a movement direction calculation program, and a movement direction calculation method that are attached to a walking body and calculate the movement direction of the walking body.

  Conventionally, many techniques for autonomously calculating the moving direction of a walking body without using a measurement signal from the outside such as a GPS signal have been provided. In order to detect the direction of movement, usually using a magnetic sensor and a gyro sensor, the direction of the body is detected using information obtained from each sensor, and the direction of the body is advanced, or The direction in which a person moves is calculated as proceeding in a preset direction.

  Specifically, for example, a combined value of the acceleration of the X axis and the Y axis between the positive value peak and the negative value peak of the Z axis acceleration using the X axis, Y axis and Z axis acceleration sensors. And a technique for obtaining a movement angle and a movement direction from the X-axis and Y-axis acceleration when the composite value is a positive peak is disclosed (for example, see Patent Documents 1 and 2 below).

JP 2003-302419 A JP 2007-325722 A

  However, in the conventional technology for determining the moving direction as described above, it is difficult to detect a peak when a pedestrian (walking body) walks with very little acceleration change like a sneaky foot. As a result, there is a problem that the accuracy of determining the moving direction is degraded. Similarly, when the pedestrian moves in a lateral direction, that is, a so-called crab walk, there is a problem that the accuracy of determining the moving direction is deteriorated for the same reason.

  In addition, the above-described special walking is assumed to be performed, for example, in a building where a criminal is standing up and when a suppression person heads for the arrangement position. However, in the case described above, there is a high possibility that the location cannot be confirmed by GPS, such as in a building, and it is difficult to grasp the position, and the configuration of the device is complicated and the size of the device is not suitable for the form. There was a problem that it would.

  In order to solve the above-described problems caused by the prior art, the present invention provides a moving direction calculation device and a moving direction capable of calculating the moving direction of the walking body with high accuracy even when the walking body has a special way of walking. It is an object to provide a calculation program and a moving direction calculation method.

  In order to solve the above-described problems and achieve the object, the movement direction calculation device, the movement direction calculation program, and the movement direction calculation method include a computer that receives an output from an acceleration sensor attached to an acceleration sensor attached to a walking body. Is a three-axis direction of an X axis that is the front direction of the walking body, a Y axis that is a right and left direction of the walking body that intersects at right angles to the front direction, and a Z axis that is a vertical direction of the walking body The correlation between the detected X-axis acceleration, the detected X-axis acceleration and the Z-axis acceleration, and the correlation between the Y-axis acceleration and the Z-axis acceleration. When the calculated XZ cross spectrum or the maximum value of the calculated YZ cross spectrum exceeds a threshold value, the XZ cross spectrum is calculated. Including a process of determining a moving direction of the moving direction of the walking body according to a comparison result of the maximum value of the spectrum and the maximum value of the YZ cross spectrum, and a process of outputting the determined direction. As a requirement.

  According to this movement direction calculation device, movement direction calculation program, and movement direction calculation method, acceleration in the Z axis direction (up and down movement) is detected by detecting triaxial acceleration and calculating an XZ cross spectrum and a YZ cross spectrum. And a correlation between an acceleration change in the X-axis direction (backward movement) and a change in an acceleration in the Z-axis direction (vertical movement) and an acceleration in the Y-axis direction (left-right movement) can be obtained. Therefore, it is used as information representing the movement of the walking body only when the vertical movement and the front-back movement or the left-right movement are linked.

  According to the movement direction calculation device, the movement direction calculation program, and the movement direction calculation method, it is possible to realize the movement direction calculation of the walking body with high accuracy even when the walking body has a special way of walking. There is an effect.

  Exemplary embodiments of a moving direction calculating device, a moving direction calculating program, and a moving direction calculating method will be described below in detail with reference to the accompanying drawings. In this movement direction calculation device, movement direction calculation program, and movement direction calculation method, in order to detect a back-and-forth movement or a right-and-left movement that correlates with the vertical direction peculiar to walking of a walking body that performs biped walking including humans Since the cross spectrum with the Z-axis direction is calculated from the accelerations in the three-axis directions of X, Y, and Z, and the direction in which the cross spectrum is maximum is determined as the movement direction, highly accurate movement direction determination without erroneous determination is performed. Can be realized.

(Overview of moving direction calculation process)
First, an outline of the movement direction calculation process according to the present embodiment will be described. FIG. 1-1 is an explanatory diagram illustrating an outline of a moving direction calculation process. As illustrated in FIG. 1A, in this embodiment, the walking direction calculation device 110 is attached to the walking body 100. The moving direction calculation device 110 includes a detection unit 111, a cross spectrum calculation unit 112, a determination unit 113, and an output unit 114.

  As illustrated in FIG. 1A, the detection unit 111 includes an X-axis that is the front direction of the walking body 100, a Y-axis that is the left-right direction of the walking body 100 that intersects at right angles to the front direction, and the walking body 100. The acceleration in the three-axis direction with respect to the Z-axis, which is the vertical direction, is detected. In the present embodiment, the names X, Y, and Z are given in the directions shown in FIG. 1-1 for convenience, but the names are not particularly limited as long as the accelerations in these three directions can be detected.

  The cross spectrum calculation unit 112 calculates an XZ cross spectrum representing the correlation between the acceleration in the X axis direction detected by the detection unit 111 and the acceleration in the Z axis direction. At the same time, the cross spectrum calculation unit 112 also calculates a YZ cross spectrum representing the correlation between the acceleration in the Y axis direction detected by the detection unit 111 and the acceleration in the Z axis direction. The XZ cross spectrum and YZ cross spectrum calculated by the cross spectrum calculation unit 112 are output to the determination unit 113.

  When the maximum value of the XZ cross spectrum or the YZ cross spectrum calculated by the cross spectrum calculation unit 112 is equal to or greater than a preset threshold value (either one needs to be equal to or greater than the threshold value) In addition, it is determined that the walking body 100 is walking, and processing for determining the moving direction is started. When the maximum value of any cross spectrum is less than the threshold value, it is determined that the user is not walking, and a stop state is output and a standby state is entered.

  The discriminating unit 113 discriminates the moving direction of the walking body 100 according to the comparison result between the maximum value of the XZ cross spectrum and the maximum value of the YZ cross spectrum. Therefore, the determination unit 113 first determines whether the moving body 100 is moving in the front-rear direction or the left-right direction. Specifically, the determination unit 113 compares the maximum value of the XZ cross spectrum with the maximum value of the YZ cross spectrum. When it is determined by this comparison that the maximum value of the XZ cross spectrum is large, it is determined that the walking body 100 is moving in the front-rear direction, and when it is determined that the maximum value of the YZ cross spectrum is large, the walking body 100 is determined. Is determined to be moving in the left-right direction.

  When it is determined whether the determination unit 113 is moving in the front-rear direction or the left-right direction, the determination unit 113 further proceeds to a process of determining whether it is moving in the front-rear direction or the left-right direction. When it is determined that the walking body 100 is moving in the front-rear direction, the determination unit 113 determines that the phase difference calculated from the real part and the imaginary part of the maximum value of the XZ cross spectrum falls within −90 ° to 90 °. It is determined that the walking body 100 is moving in the forward direction, and if it does not fit, it is determined that the walking body 100 is moving in the backward direction.

  On the other hand, when it is determined that the walking body 100 is moving in the left-right direction, the determination unit 113 causes the phase difference calculated from the real part and the imaginary part of the maximum value of the YZ cross spectrum to be −90 ° to 90 °. If it is within the range, it is determined that the walking body 130 is moving in the right direction. If it is not within the range, it is determined that the walking body 100 is moving in the left direction.

  Here, FIG. 1-2 is an explanatory diagram illustrating the relationship between the phase difference of the cross spectrum and the movement direction. A unit circle 120 in FIG. 1-2 represents the relationship between the phase difference calculated from the real part and the imaginary part of the XZ cross spectrum and the moving direction. Therefore, as shown in the unit circle 120, if the phase difference has a value of −90 ° to 90 °, it is determined that the phase is moving in the forward direction, and a value of 91 ° to 180 ° or a value of −91 ° to −179 °. If it becomes, it will be discriminate | determined moving to back direction. Similarly, the unit circle 130 shows the relationship between the phase difference calculated from the real part and the imaginary part of the YZ cross spectrum and the moving direction. Therefore, as shown in the unit circle 130, if the phase difference has a value of −90 ° to 90 °, it is determined that the movement is in the right direction, and a value of 91 ° to 180 ° or −91 ° to −179 °. If it becomes, it will be discriminate | determined moving to the left direction. Note that it is possible to adjust how the values near 90 ° and 270 ° are determined. For example, in accordance with the detection tendency of the detection unit 111, it may be set so that it is determined that the vehicle travels forward from -89 ° to 89 ° and the vehicle travels backward when the value is other than that.

  In addition, the determination unit 113 includes a rush determination function unit. The running foot discriminating function unit discriminates whether or not the walking body 100 is moving on a running foot. When it is determined that the walking body 100 is moving with a running foot by the running foot discrimination function unit, the body of the moving body 100 jumps up, so that the acceleration in the moving direction detected by the detection unit 111 is reversed. It is in. Therefore, the determination unit 113 is provided with a correction function unit that corrects the direction determined as the moving direction in the opposite direction when it is determined that the running is determined by the running determination unit.

  In addition, as a run-up discrimination | determination function part, you may mount a well-known run-up discrimination apparatus, and you may discriminate | determine using the triaxial acceleration detected by the detection part 111. FIG. For example, in a predetermined cycle, the maximum value of the acceleration in the X axis direction or the acceleration in the Y axis direction detected by the detection unit 111 is equal to or greater than a threshold value, and the frequency component of the maximum value is equal to or greater than the threshold value. When there exists, the structure which discriminate | determines that the walking body 100 is moving with a rush is mentioned.

  The output unit 114 outputs the moving direction of the walking body 100 determined by the determination unit 113 to the outside. If the determination unit 113 determines that the vehicle is running, the direction corrected by the correction function unit in the opposite direction is output. The output destination by the output unit 114 can be arbitrarily set. For example, a display unit (not shown) may be attached to the movement direction calculation device 110 to display the calculation result on the walking body 100 itself, or may be transmitted to other devices via a communication I / F (interface). Good.

  As described above, in the present embodiment, it is possible to determine the back-and-forth movement or the right-and-left movement linked to the vertical movement by detecting the acceleration in the triaxial direction for the moving body 100 and calculating the cross spectrum from the acceleration. it can. Therefore, since the direction determination is performed only when the walking body 100 is driven and moved, a movement caused by other than walking or a change in acceleration is erroneously detected as walking by the walking body 100. The situation can be prevented and the moving direction can be detected with high accuracy. In addition, since the acceleration value in the Z-axis direction is small, special walking such as sneak foot and crab walking, which has been difficult to detect in the past, can be performed in the X-axis direction or the Y-axis direction even if the acceleration in the Z-axis direction is small. If the correlation with the movement is high, it is detected as walking, so that the moving direction can be determined without overlooking.

  Hereinafter, specific configuration examples and processing procedures for realizing the movement direction calculation processing according to the present embodiment will be described in order.

(Hardware configuration of moving direction calculation device)
First, the hardware configuration of the moving direction calculation apparatus according to this embodiment will be described. FIG. 2 is a block diagram illustrating a hardware configuration of the moving direction calculation apparatus. As shown in FIG. 1-1, the moving direction calculation device 110 is a small device of a cigarette box size. Further, the moving direction calculation device 110 may be an existing terminal such as a PDA (Personal Digital Assistant) or a PC (Personal Computer) added with a hardware configuration described below, or includes a dedicated housing. It may be a device.

  Further, the movement direction calculation device 110 includes a CPU 201, a ROM 202, a RAM 203, an HDD (hard disk drive) 204, an HD (hard disk) 205, a memory drive 206, a removable memory 207 as a removable recording medium, A display 208, an input I / F (interface) 209, various sensors 210, and a network I / F 211 are provided. Each component is connected by a bus 220.

  Here, the CPU 201 governs overall control of the movement direction calculation device 110. The ROM 202 stores a program such as a boot program. The RAM 203 is used as a work area for the CPU 201. The HDD 204 controls data read / write with respect to the HD 205 according to the control of the CPU 201. The HD 205 stores data written under the control of the HDD 204.

  The memory drive 206 controls reading / writing of data with respect to the removable memory 207 according to the control of the CPU 201. The removable memory 207 stores data written under the control of the memory drive 206 or causes the memory drive 206 to read data stored in the removable memory 207 under the control of the CPU 201.

  The display 208 displays data related to the movement direction calculation result using a document, an image, as well as a cursor, icon, or tool box. As the display 208, for example, a CRT, a TFT liquid crystal display, a plasma display, or the like can be adopted.

  The input I / F 209 includes keys for inputting characters, numbers, various instructions, and the like, and inputs data. Moreover, a touch panel type input pad or a numeric keypad may be used. The input unit of the input I / F 209 may be a pointing device such as a touch panel or a trackball.

  The various sensors 210 are composed of sensors having different functions for measuring information for calculating the moving direction. Specifically, an acceleration sensor for detecting the walking interval of the walking body 100, and a magnetic sensor and a gyro sensor for calculating the moving direction of the walking body 100 are mounted. In the case of the moving direction calculation device 110 according to the present embodiment, the acceleration sensor is an essential configuration, but other sensors are optional.

  The network I / F 211 connects to the network 230 such as the Internet through the communication line 212 regardless of wired wireless, and connects the movement direction calculation device 110 to other devices via the network 230. The network I / F 211 controls an internal interface with the network 230 and controls data input / output from an external device. As the network I / F 211, for example, a modem or a LAN adapter can be employed.

(Functional configuration of moving direction calculation device)
Next, a functional configuration of the moving direction calculation apparatus according to the present embodiment will be described. FIG. 3 is a block diagram illustrating a functional configuration of the moving direction calculation apparatus. As illustrated in FIG. 3, the moving direction calculation device 110 includes a sensor unit 310, an arithmetic processing unit 320, a storage unit 330, a display unit 340, and a communication unit 350.

  The sensor unit 310 includes three types of sensors: an acceleration sensor 311, a magnetic sensor 312, and a gyro sensor 313. From these sensors, the operation content accompanying the movement of the walking body 100 is continuously detected at predetermined intervals. The sensor unit 310 is realized by, for example, the various sensors 210 described with reference to FIG. Further, as described above, it is arbitrary whether a sensor other than the acceleration sensor 311 is mounted.

  The arithmetic processing unit 320 is a functional unit that calculates the moving direction of the walking body 100 using the detection value acquired from the sensor unit 310. The arithmetic processing unit 320 is realized by, for example, the CPU 201, the ROM 202, and the RAM 203 described with reference to FIG.

  The storage unit 330 is a storage area that stores predetermined information according to the control of the CPU 201. Information stored in the storage unit 330 includes input information 331, output information 332, setting parameters 333 necessary for calculation processing, a determination table 334 in which determination processing contents and determination criteria are set, and a calculation algorithm used for the calculation processing. There are 335. The storage unit 330 is implemented by, for example, the HDD 204, HD 205, memory drive 206, and removable memory 207 described with reference to FIG.

  The display unit 340 and the communication unit 350 function as an output unit that outputs the movement direction calculation result of the walking body 100 calculated by the calculation processing unit 320. The display unit 340 can notify the walking body 100 itself of the movement direction calculation result using a display device such as a liquid crystal display. Moreover, since the communication part 350 can transmit a moving direction calculation result to another apparatus and a predetermined address, it can alert | report the moving direction of the walking body 100 with respect to others.

  In addition to the movement direction calculation result, the communication unit 350 can acquire the setting parameter 333, the determination table 334, and the calculation algorithm 335 necessary for calculation in the calculation processing unit 320 from the outside through communication with an external device. it can. The display unit 340 is realized by, for example, the display 208 in FIG. Moreover, the communication part 350 is implement | achieved by network I / F211 of FIG. 2, for example.

(Movement direction calculation procedure)
Next, a procedure of movement direction calculation processing in the movement direction calculation apparatus 110 will be described. FIGS. 4A and 4B are flowcharts illustrating the procedure of the movement direction calculation process. Each process illustrated in FIG. 4A is a process for calculating movement calculation information from the accelerations in the three-axis directions detected by the detection unit 111, which is a preparation process for determining the movement direction.

  In the flowchart of FIG. 4A, first, X-, Y-, and Z-axis accelerations are acquired from the acceleration sensor 311 at predetermined intervals (step S401). As the predetermined cycle, the walking interval for each step of the walking body 100 may be set as one cycle. Therefore, the walking interval of the walking body 100 on which the moving direction calculation device 110 is mounted may be measured in advance and set as a cycle, or an average walking interval (for example, every 2 seconds) is set as an initial value. You may keep it.

  Next, the frequency component of the acquired acceleration of each axis is calculated by the arithmetic processing unit 320 (step S402). In step S402, in order to calculate the frequency component, the detected acceleration may be converted by, for example, FFT (Finite Fourier transform). As a specific example, the acceleration in the X, Y, and Z axis directions can be subjected to Fourier transformation as shown in the following formulas (1) to (3), and can be expressed using an imaginary unit j.

After that, the arithmetic processing unit 320 further calculates an XZ cross spectrum representing the correlation between the accelerations from the frequency components of the X-axis and Z-axis accelerations calculated in step S402 (step S403). When the above equations (1) and (3) are used as an example of calculating the frequency component, the cross spectrum (XZ cross spectrum) = S _XZ (kΔf) between the acceleration in the X-axis direction and the acceleration in the Z-axis direction is 4) It becomes like a formula. Further, the complex conjugate function F ^* _X (kΔf) of S _XZ (kΔf) is expressed by the following equation (5). Therefore, the real part S _XZR (kΔf) of the XZ cross spectrum is expressed by the following formula (6), and the imaginary part S _XZJ (kΔf) of the XZ cross spectrum is expressed by the following formula (7).

Once the XZ cross spectrum is calculated, the maximum value XZmax of the XZ cross spectrum is then calculated (step S404). The maximum value XZmax of the XZ cross spectrum is the amplitude A _XZ when the cross spectrum S _XZ (kΔf) is maximum. Therefore, the amplitude A _XZ when the cross spectrum S _XZ (kΔf) is maximum may be calculated by the following equation (8).

In the arithmetic processing unit 320, processing for the cross spectrum YZ is also executed in parallel with the processing of steps S403 and S404 described above. A YZ cross spectrum representing the correlation between the accelerations is further calculated from the frequency components of the Y-axis and Z-axis accelerations calculated in step S402 (step S405). When the above formulas (2) and (3) are used as an example of calculating the frequency component, the cross spectrum (YZ cross spectrum) = S _YZ (kΔf) between the acceleration in the Y-axis direction and the acceleration in the Z-axis direction is 9) It becomes like a formula. The complex conjugate function F ^* _Y (kΔf) of S _YZ (kΔf) is expressed by the following equation (10). Therefore, the real part S _YZR (kΔf) of the YZ cross spectrum is expressed by the following formula (11), and the imaginary part S _YZJ (kΔf) of the XZ cross spectrum is expressed by the following formula (12).

Once the YZ cross spectrum is calculated, the maximum value YZmax of the YZ cross spectrum is then calculated (step S406). Here, similarly to the calculation in step S404, the amplitude A _YZ when the cross spectrum S _YZ (kΔf) is maximum may be calculated. Therefore, the value calculated as the amplitude A _YZ when the cross spectrum S _YZ (kΔf) is maximum according to the following equation (13) is the maximum value YZmax of the YZ cross spectrum.

  Then, the maximum value XZmax of the XZ cross spectrum is calculated in step S404, and it is determined whether the maximum value YZmax of the YZ cross spectrum is calculated in step S406 (step S407). Here, the process waits until both calculations are completed (step S407: No loop). When the calculation is completed (step S407: Yes), a process for specifically determining the moving direction (FIG. 4-2, step S408). To).

  Next, each process in FIG. 4B will be described. Each process illustrated in FIG. 4B is a process of determining in which direction the walking body 100 is specifically moving. First, it is determined whether either the maximum value XZmax of the XZ cross spectrum or the maximum value YZmax of the YZ cross spectrum is larger than the threshold value (step S408). The threshold value used as the determination criterion in step S408 may be set to a minimum value that occurs when the walking body 100 moves regardless of how to walk.

  Here, FIG. 5 is a chart showing a calculation example of the XZ cross spectrum maximum value during walking. As shown in the chart 500, there is a large difference in the maximum XZ cross spectrum value when the walking body 100 is stopped and when walking. Therefore, as shown in the chart 500, the average of the maximum value at the time of stop + the error may be set as the threshold value.

  Returning to FIG. 4B, when it is determined that either the maximum value XZmax of the XZ cross spectrum or the maximum value YZmax of the YZ cross spectrum is larger than the threshold value (step S408: Yes), then, the XZ cross It is determined whether or not the maximum value XZmax of the spectrum is larger than the maximum value YZmax of the YZ cross spectrum (step S409). Based on this determination, it is selected whether to use the cross spectrum considering the X-axis direction or the Y-axis direction to determine the moving direction.

  Here, FIG. 6 is a chart showing a calculation example of the maximum values of the XZ cross spectrum and the YZ cross spectrum at the time of the previous progress. From the calculated maximum values of the two cross spectra, the acceleration in the direction of actual movement (front and rear or left and right) is detected to be larger. Therefore, as shown in the chart 600, the maximum value XZmax of the XZ cross spectrum increases during advance.

  Therefore, when it is determined that the maximum value XZmax of the XZ cross spectrum is larger than the maximum value YZmax of the YZ cross spectrum (step S409: Yes), it is determined that the XZ cross spectrum is moving in the front-rear direction, and the maximum value XZmax of the XZ cross spectrum is determined. Is determined not to be larger than the maximum value YZmax of the YZ cross spectrum (step S409: No), it is determined that the movement is in the left-right direction, and the process proceeds to the process according to the determination result.

Returning to FIG. 4B, first, a process when it is determined that the robot has moved in the front-rear direction will be described. First, the phase difference XZpha between the real part and the imaginary part of the frequency component in the maximum value XZmax of the XZ cross spectrum is calculated (step S410). In order to calculate the phase difference XZpha, the phase difference Θ _XZ when the cross spectrum S _XZ (kΔf) is maximum may be calculated using the following equation (14).

  FIG. 7 is a chart showing a calculation example of the phase difference at the time of forward movement. FIG. 8 is a chart showing an example of calculating the phase difference during reverse travel. As shown in the charts 700 and 800, the phase difference during walking converges to a specific value according to the moving direction. Specifically, as described with reference to FIG. 1B, when the angle is within −90 ° to 90 °, the vehicle moves forward, and when it does not, the vehicle moves backward. Therefore, returning to FIG. 4B, it is next determined whether or not the phase difference XZpha calculated in step S410 is an angle that falls between −90 ° and 90 ° (step S411).

  When the phase difference XZpha is an angle that falls between −90 ° and 90 ° (step S411: Yes), it is determined that the walking body 100 is moving forward (step S412). If the phase difference XZpha is an angle that does not fall between −90 ° and 90 ° (step S411: No), it is determined that the walking body 100 is moving backward (step S413).

Next, a process when it is determined that the object has moved in the left-right direction will be described. FIG. 9 is a chart showing a calculation example of the maximum values of the XZ cross spectrum and the YZ cross spectrum during right walking. From the calculated maximum values of the two cross spectra, the acceleration in the direction of actual movement (front and rear or left and right) is detected to be larger. Therefore, as shown in the chart 900, the maximum value XZmax of the cross spectrum increases when moving left and right. Therefore, next, the phase difference YZpha between the real part and the imaginary part of the frequency component in the maximum value YZmax of the YZ cross spectrum is calculated (step S414). In order to calculate the phase difference YZpha, the phase difference Θ _YZ when the cross spectrum S _YZ (kΔf) is maximum may be calculated using the following equation (15).

  FIG. 10 is a chart showing an example of calculating the phase difference during right walking. FIG. 11 is a chart showing an example of calculating the phase difference during left walking. As in the charts 1000 and 1100, the phase difference during walking converges to a specific value according to the moving direction. Specifically, as described with reference to FIG. 1-2, a right walk is indicated when the angle is within −90 ° to 90 °, and a left walk is indicated when the angle is not within the range. Accordingly, returning to FIG. 4B, it is determined whether or not the phase difference YZpha calculated in step S414 is within an angle between −90 ° and 90 ° (step S415).

  When the phase difference YZpha is an angle that falls between −90 ° and 90 ° (step S415: Yes), the walking body 100 is determined to be walking right (step S416). If the phase difference YZpha is an angle that does not fall between −90 ° and 90 ° (step S415: No), it is determined that the walking body 100 is walking left (step S417).

  Next, it is determined whether or not the walking body 100 is walking on foot (step S418). Here, FIG. 12 is a chart showing a calculation example of the phase difference at the time of running. The chart 1200 shows the XZ phase difference calculated at the time of forward movement, but since it was a rush, the value at the time of backward movement has been calculated. Therefore, when running, it is necessary to correct the calculation value. Returning to FIG. 4-2, when it is determined in step S418 that the walking body 100 is not running and is walking normally (step S418: No), the determination results in steps S412, S413, S416, and S417 are displayed. It outputs as the moving direction of the walking body 100 (step S419), and a series of processes are complete | finished as it is.

  On the other hand, if it is determined in step S418 that the walking body 100 is walking on the ground (step S418: Yes), the acceleration acquired in step S401 is a value obtained by inverting the actual movement direction. The discrimination results in steps S412, S413, S416, and S417 are reversed, and the reverse direction is output as the moving direction of the walking body 100 (step S420), and the series of processing ends.

  If it is determined in step S408 that either the maximum value XZmax of the XZ cross spectrum or the maximum value YZmax of the YZ cross spectrum is less than the threshold value (step S408: No), the walking object 100 is Since it is not a walking state, it is determined that the vehicle is in a stopped state (step S421).

  Note that the threshold value setting and the phase difference determination criteria in FIG. 4-2 described above are appropriately set according to the characteristics of the acceleration sensor 311 (see FIG. 3) for detecting acceleration and the walking motion of the walking body 100. You may adjust. Further, when the maximum value XZmax of the XZ cross spectrum is equal to the maximum value YZmax of the YZ cross spectrum, it is determined that the movement is performed in the forward / backward or left / right direction by feeding back to the operation result or the like. Set it to.

  As described above, in the moving direction calculation device 110 of the present embodiment, the acceleration sensor 311 only needs to detect the acceleration of the three axes from the outside, and even after the detection, the value related to the cross spectrum is calculated and compared. Thus, the moving direction can be determined. Therefore, the hardware configuration essential for the moving direction calculation apparatus 110 is small, and the required processing capability is not high. As a result, the processing load on the movement direction calculation device 110 can be reduced. In addition, since direction determination is executed only when the walking body 100 is driven and moved, a movement caused by other than walking or a change in acceleration is erroneously detected as walking by the walking body 100. A situation can be prevented and highly accurate movement direction detection can be realized.

  In addition, when the position information of the moving body is specified using the other sensors (magnetic sensor 312 and gyro sensor 313) described with reference to FIG. 3, it is associated with the determination result of the moving direction, It is also possible to determine which is moving.

  The moving direction calculation method described in this embodiment can be realized by executing a program prepared in advance on a computer such as a personal computer or a workstation. This program is recorded on a computer-readable recording medium such as a hard disk, a flexible disk, a CD-ROM, an MO, and a DVD, and is executed by being read from the recording medium by the computer. The program may be a medium that can be distributed via a network such as the Internet.

  Further, the moving direction calculation device 110 described in the present embodiment is a PLD (hereinafter simply referred to as “ASIC”) such as a standard cell or a structured specific integrated circuit (ASIC) (hereinafter simply referred to as “ASIC”) or a PLD (such as an FPGA). It can also be realized by Programmable Logic Device). Specifically, for example, the function (111 to 114) of the moving direction calculation device 110 described above is defined by HDL description, and the HDL description is logically synthesized and given to the ASIC or PLD, thereby moving direction calculation device 110. Can be manufactured.

  The following additional notes are disclosed with respect to the embodiment described above.

(Supplementary Note 1) Three axes: an X-axis that is the front direction of the walking body, a Y-axis that is the left-right direction of the walking body that intersects at right angles to the front direction, and a Z-axis that is the vertical direction of the walking body Detecting means for detecting the acceleration in the direction;
An XZ cross spectrum representing the correlation between the acceleration in the X-axis direction and the acceleration in the Z-axis direction detected by the detection means, and a YZ cross-spectrum representing the correlation between the acceleration in the Y-axis direction and the acceleration in the Z-axis direction. Cross spectrum calculation means for calculating
Comparison between the maximum value of the XZ cross spectrum and the maximum value of the YZ cross spectrum when the maximum value of the XZ cross spectrum or YZ cross spectrum calculated by the cross spectrum calculating means is equal to or greater than a threshold value. Direction discriminating means for discriminating the moving direction of the walking body according to the result;
Output means for outputting the direction determined by the direction determination means;
A moving direction calculation device comprising:

(Supplementary Note 2) When the direction discriminating means compares the maximum value of the XZ cross spectrum and the maximum value of the YZ cross spectrum and determines that the maximum value of the XZ cross spectrum is large, It is determined that is moving in the front-rear direction, and when it is determined that the maximum value of the YZ cross spectrum is large, it is determined that the walking body is moving in the left-right direction. Moving direction calculation device.

(Supplementary Note 3) When it is determined that the walking body is moving in the front-rear direction, the direction determination unit has a phase difference calculated from the real part and the imaginary part of the maximum value of the XZ cross spectrum of −90 °. The supplementary note 2 is characterized in that it is determined that the walking body is moving in the forward direction if it is within ~ 90 °, and that the walking body is moving in the backward direction if it is not within the range. Moving direction calculation device.

(Additional remark 4) When it is discriminate | determined that the said walking body is moving in the left-right direction, the said direction discrimination | determination means has a phase difference calculated from the real part and imaginary part of the maximum value of the said YZ cross spectrum -90 degrees. The supplementary note 2 is characterized in that it is determined that the walking body is moving in the forward direction if it is within ~ 90 °, and that the walking body is moving in the backward direction if it is not within the range. Moving direction calculation device.

(Additional remark 5) The run-up discrimination means which discriminate | determines whether the said walking body is moving by run-up,
Correction means for correcting the direction determined as the moving direction by the direction determining means in the opposite direction when the walking body is determined to be moving by the running distance determining means;
The movement direction calculation apparatus according to any one of Supplementary notes 1 to 4, wherein the output unit outputs the direction corrected by the correction unit.

(Supplementary note 6) The running speed determination means is configured such that, in a predetermined cycle, the maximum value of the XZ cross spectrum or YZ cross spectrum detected by the detection means is not less than a threshold value and the frequency of the maximum value is not less than the threshold value. If there is, the moving direction calculating device according to appendix 5, wherein it is determined that the walking body is moving on a rush.

(Additional remark 7) The said direction discrimination means discriminate | determines that the said walking body is a stop state, when the maximum value of the XZ cross spectrum or YZ cross spectrum calculated by the said cross spectrum calculation means becomes less than a threshold value. The moving direction calculation device according to any one of appendices 1 to 6, characterized in that:

(Appendix 8) A computer for receiving an output from an acceleration sensor attached to an acceleration sensor attached to a walking body,
Acceleration in the three-axis direction of the X axis that is the front direction of the walking body, the Y axis that is the left-right direction of the walking body that intersects at right angles to the front direction, and the Z axis that is the vertical direction of the walking body Detecting means for detecting
An XZ cross spectrum representing the correlation between the acceleration in the X-axis direction and the acceleration in the Z-axis direction detected by the detection means, and a YZ cross-spectrum representing the correlation between the acceleration in the Y-axis direction and the acceleration in the Z-axis direction. Cross spectrum calculation means for calculating
Comparison between the maximum value of the XZ cross spectrum and the maximum value of the YZ cross spectrum when the maximum value of the XZ cross spectrum or YZ cross spectrum calculated by the cross spectrum calculating means is equal to or greater than a threshold value. Direction discriminating means for discriminating the moving direction of the walking body according to the result,
Output means for outputting the direction determined by the direction determination means;
It is made to function as a moving direction calculation program characterized by the above-mentioned.

(Supplementary note 9) A device that receives an output from an acceleration sensor attached to an acceleration sensor attached to a walking body,
Acceleration in the three-axis direction of the X axis that is the front direction of the walking body, the Y axis that is the left-right direction of the walking body that intersects at right angles to the front direction, and the Z axis that is the vertical direction of the walking body A detection step for detecting
An XZ cross spectrum representing the correlation between the acceleration in the X-axis direction and the acceleration in the Z-axis direction detected by the detection step, and a YZ cross spectrum representing the correlation between the acceleration in the Y-axis direction and the acceleration in the Z-axis direction. A cross spectrum calculation step for calculating
Comparison between the maximum value of the XZ cross spectrum and the maximum value of the YZ cross spectrum when the maximum value of the XZ cross spectrum or the YZ cross spectrum calculated by the cross spectrum calculation step exceeds a threshold value A direction discriminating step for discriminating the moving direction of the walking body according to the result;
An output step for outputting the direction determined by the direction determination step;
The moving direction calculation method characterized by performing.

It is explanatory drawing which shows the outline | summary of a moving direction calculation process. It is explanatory drawing which shows the relationship between the phase difference of a cross spectrum, and a moving direction. It is a block diagram which shows the hardware constitutions of a moving direction calculation apparatus. It is a block diagram which shows the functional structure of a moving direction calculation apparatus. It is a flowchart (the 1) which shows the procedure of a moving direction calculation process. It is a flowchart (the 2) which shows the procedure of a moving direction calculation process. It is a chart which shows the example of calculation of the XZ cross spectrum maximum value at the time of walking. It is a graph which shows the example of calculation of the maximum value of the XZ cross spectrum at the time of advancing, and a YZ cross spectrum. It is a graph which shows the example of calculation of the phase difference at the time of advance. It is a chart which shows the example of calculation of the phase difference at the time of reverse. It is a graph which shows the example of calculation of the maximum value of the XZ cross spectrum at the time of right walk, and a YZ cross spectrum. It is a graph which shows the example of calculation of the phase difference at the time of right walk. It is a graph which shows the example of calculation of the phase difference at the time of left walking. It is a chart which shows the example of calculation of the phase difference at the time of running.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Walking body 110 Moving direction calculation apparatus 111 Detection part 112 Cross spectrum calculation part 113 Discriminating part 114 Output part 201 CPU
202 ROM
203 RAM
204 HDD
205 HD
206 Memory Drive 207 Removable Memory 208 Display 209 Input I / F
210 Various sensors 211 Network I / F
220 Bus 230 Network (NET)
310 sensor unit 311 acceleration sensor 312 magnetic sensor 313 gyro sensor 320 arithmetic processing unit 330 storage unit 331 input information 332 output information 333 setting parameter 334 determination table 335 calculation algorithm 340 display unit 350 communication unit

Claims (7)

The acceleration in the three-axis direction of the X-axis that is the front direction of the walking body, the Y-axis that is the left-right direction of the walking body that intersects at right angles to the front direction, and the Z-axis that is the vertical direction of the walking body Detecting means for detecting;
An XZ cross spectrum representing the correlation between the acceleration in the X-axis direction and the acceleration in the Z-axis direction detected by the detection means, and a YZ cross-spectrum representing the correlation between the acceleration in the Y-axis direction and the acceleration in the Z-axis direction. Cross spectrum calculation means for calculating
Comparison between the maximum value of the XZ cross spectrum and the maximum value of the YZ cross spectrum when the maximum value of the XZ cross spectrum or YZ cross spectrum calculated by the cross spectrum calculating means is equal to or greater than a threshold value. Direction discriminating means for discriminating the moving direction of the walking body according to the result;
Output means for outputting the direction determined by the direction determination means;
A moving direction calculation device comprising:   When the direction discriminating unit compares the maximum value of the XZ cross spectrum with the maximum value of the YZ cross spectrum and determines that the maximum value of the XZ cross spectrum is large, the walking body moves in the front-rear direction. 2. The moving direction according to claim 1, wherein it is determined that the walker is moving in the left-right direction when it is determined that the walker is moving and the maximum value of the YZ cross spectrum is determined to be large. Calculation device.   When it is determined that the walking body is moving in the front-rear direction, the direction determination unit has a phase difference calculated from the real part and the imaginary part of the maximum value of the XZ cross spectrum between −90 ° and 90 °. 3. The moving direction calculation according to claim 2, wherein if it is settled, it is determined that the walking body is moving in the forward direction, and if it is not settled, it is determined that the walking body is moving in the backward direction. apparatus.   When it is determined that the walking body is moving in the left-right direction, the direction determining means has a phase difference calculated from the real part and the imaginary part of the maximum value of the YZ cross spectrum between −90 ° and 90 °. 3. The moving direction calculation according to claim 2, wherein if it is settled, it is determined that the walking body is moving in the forward direction, and if it is not settled, it is determined that the walking body is moving in the backward direction. apparatus. Rushing determining means for determining whether or not the walking body is moving with rushing;
Correction means for correcting the direction determined as the moving direction by the direction determining means in the opposite direction when the walking body is determined to be moving by the running distance determining means;
The movement direction calculation apparatus according to claim 1, wherein the output unit outputs the direction corrected by the correction unit. A computer that receives the output from the acceleration sensor attached to the acceleration sensor attached to the walking body,
Acceleration in the three-axis direction of the X axis that is the front direction of the walking body, the Y axis that is the left-right direction of the walking body that intersects at right angles to the front direction, and the Z axis that is the vertical direction of the walking body Detecting means for detecting
An XZ cross spectrum representing the correlation between the acceleration in the X-axis direction and the acceleration in the Z-axis direction detected by the detection means, and a YZ cross-spectrum representing the correlation between the acceleration in the Y-axis direction and the acceleration in the Z-axis direction. Cross spectrum calculation means for calculating
Comparison between the maximum value of the XZ cross spectrum and the maximum value of the YZ cross spectrum when the maximum value of the XZ cross spectrum or YZ cross spectrum calculated by the cross spectrum calculating means is equal to or greater than a threshold value. Direction discriminating means for discriminating the moving direction of the walking body according to the result,
Output means for outputting the direction determined by the direction determination means;
It is made to function as a moving direction calculation program characterized by the above-mentioned. A device that receives an output from an acceleration sensor attached to an acceleration sensor attached to a walking body,
Acceleration in the three-axis direction of the X axis that is the front direction of the walking body, the Y axis that is the left-right direction of the walking body that intersects at right angles to the front direction, and the Z axis that is the vertical direction of the walking body A detection step for detecting
An XZ cross spectrum representing the correlation between the acceleration in the X-axis direction and the acceleration in the Z-axis direction detected by the detection step, and a YZ cross spectrum representing the correlation between the acceleration in the Y-axis direction and the acceleration in the Z-axis direction. A cross spectrum calculation step for calculating
Comparison between the maximum value of the XZ cross spectrum and the maximum value of the YZ cross spectrum when the maximum value of the XZ cross spectrum or the YZ cross spectrum calculated by the cross spectrum calculation step exceeds a threshold value A direction discriminating step for discriminating the moving direction of the walking body according to the result;
An output step for outputting the direction determined by the direction determination step;
The moving direction calculation method characterized by performing.

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