JP7035440B2 - Position measurement method, electronic equipment and positioning system - Google Patents

Description

The present invention relates to a position measuring method and the like for measuring position information using a measurement signal of an inertial measurement unit.

Portable electronic devices, so-called runner's watches, that are worn on the wrists of users who perform exercises such as running and marathons are becoming widespread. Such electronic devices have built-in inertial measurement units such as acceleration sensors and gyro sensors, and information on the user's motion such as the user's position, speed, and distance traveled by inertial navigation calculations using the measured values of the inertial measurement unit. Some have a function of displaying the image in real time (see, for example, Patent Document 1).

U.S. Patent Application Publication No. 2003/0216865

By the way, the measured value output by the inertial measurement unit includes a bias (error), and this bias may cause a large error in the inertial navigation calculation result. In order to deal with this, for example, in Patent Document 1 described above, GPS (Global Positioning System) positioning is performed in parallel, and the bias included in the measured value of the inertial measurement unit is estimated by the Kalman filter using this positioning result. -By removing it, the inertial navigation calculation result is corrected.

However, in the Kalman filter processing, the bias of the measured values of the accelerometer and the gyro sensor and the state values of the position, speed and attitude which are the results of the inertial navigation calculation are required, but the accelerometer and the gyro sensor have three axes. Since the position, speed, and attitude, which are the sensor and the result of the inertial navigation calculation, are given as triaxial component values, many values such as a total of 15 state values are required, and the processing load is large. In addition, in order to suppress the drift of the inertial navigation calculation result due to the drift of the measured value of the inertial sensor due to environmental changes and changes over time, GPS positioning is performed in parallel and the inertial navigation calculation is performed based on the GPS positioning result. Results need to be corrected frequently. The power consumption required for GPS positioning is larger than that of the inertial navigation calculation, and the processing load is also large.

An increase in processing load leads to an increase in processing time and power consumption. Since portable electronic devices are required to be smaller, lighter, and consume less power as a whole, it is required to suppress the increase in processing load as much as possible or reduce the processing load. ..

The present invention has been made in view of the above circumstances, and an object of the present invention is to achieve high accuracy while suppressing power consumption in an electronic device that measures position information using a measurement signal of an inertial measurement unit. It is to be able to measure various position information.

The first invention for solving the above-mentioned problems is a position measurement method in which an arithmetic processing unit measures position information using a measurement signal of an inertial measurement unit, and the inertial measurement unit is used for movement or movement of a user. Attached to a predetermined part of the user who moves periodically with the user, the arithmetic processing unit executes a real-time measurement process for measuring the position information, and the real-time measurement process appears periodically by the movement or movement. Estimating the speed of the user based on the signal characteristics of the measurement signal, calculating the yaw angle based on the measurement signal, and measuring the position information using the speed and the yaw angle. It is a position measurement method including.

According to the first invention, the position of the user is based on the measurement signal of the inertial measurement unit attached to the predetermined part of the user who moves periodically with the movement or movement of the user, by a method different from the conventional inertial navigation calculation. Information can be measured. Further, according to the position measurement method of the present invention, it is possible to reduce the processing load required for measuring the position information and reduce the power consumption as compared with the conventional inertial navigation calculation.

That is, if the arm is a predetermined part that moves periodically with the movement or movement of the user, the speed of the user can be estimated from the signal characteristics of the measurement signal that appears periodically by the movement of the arm periodically. Further, by calculating the yaw angle based on the measurement signal, the user's position information can be measured by using this speed and the yaw angle. Here, the speed means a speed, for example, a distance traveled per unit time, and does not include a direction of movement.

The second invention is the position measurement method of the first invention, in which the real-time measurement process obtains the acceleration of the measurement acceleration signal included in the measurement signal, and based on the change in the acceleration, the measurement acceleration signal of the measurement acceleration signal is obtained. A position measuring method comprising determining a period and calculating the amplitude of the measured acceleration signal based on the period, the estimation comprising estimating the speed based on the amplitude. Is.

According to the second invention, the estimation of the user's speed based on the measurement signal can be performed based on the amplitude of the measurement acceleration signal included in the measurement signal.

A third aspect of the invention is the position measuring method of the first or second invention, in which the arithmetic processing unit determines whether the user is performing or stopping the locomotion based on the measurement signal. It is a position measurement method that determines the behavior type of the user including at least the above, and executes the real-time measurement process when it is determined that the locomotion is being performed.

According to the third invention, the real-time measurement process for measuring the user's position information can be executed when it is determined that the user is performing a locomotion based on the measurement signal. That is, since it is possible to determine whether or not the user is performing an arm swinging motion based on the measurement signal, it is possible to determine an action type such as whether or not the user is performing a locomotion or stopping. Then, the user's position information can be measured only when the user is moving, and the position information measurement can be stopped when the user is stopped, so that unnecessary power consumption can be suppressed. can.

The fourth invention is the position measuring method of any one of the first to third inventions, and the real-time measurement processing includes calculating a moving distance, measuring the elapsed time of the moving motion, and measuring the elapsed time of the moving motion. It is a position measurement method including calculating the time required for movement of a predetermined unit distance based on the movement distance and the elapsed time.

According to the fourth invention, it is possible to calculate the travel distance and the elapsed time of the locomotion, and to calculate information about running or marathon such as lap time and pace.

A fifth aspect of the invention is the position measurement method according to any one of the first to fourth aspects, wherein the user has a satellite positioning device attached to the predetermined portion or another portion, and the real-time measurement process is performed. , Control to acquire reference navigation information by causing the satellite positioning device to perform measurement operation at a given timing, and correct the estimated speed based on the reference speed included in the reference navigation information. It is a position measurement method including to do.

According to the fifth invention, a satellite positioning device mounted on a predetermined part of the user or another part is made to perform a measurement operation to acquire reference navigation information, and an estimation is made based on the reference speed information included in the reference navigation information. By correcting the speed, the accuracy of position information measurement can be improved.

The sixth invention is the position measurement method of any one of the first to fourth inventions, wherein the user has a satellite positioning device attached to the predetermined portion or another portion, and the real-time measurement process is performed. By having the satellite positioning device perform a measurement operation at a given timing, control for acquiring reference navigation information is performed, and the measurement result of the real-time measurement process is recorded in association with the measurement time. The arithmetic processing apparatus executes a correction process of correcting the measurement result of the real-time measurement process by using the reference navigation information, including recording the reference navigation information in association with the acquisition time. It is a position measurement method.

According to the sixth invention, it is possible to correct the measurement result of the real-time measurement process by using the reference navigation information acquired by performing the measurement operation on the satellite positioning device attached to the predetermined part of the user or another part. .. This makes it possible to improve the accuracy of the measured position information.

A seventh aspect of the invention is the position measuring method of the sixth invention, in which the user has terminated the locomotion of the arithmetic processing unit based on a predetermined termination operation of the user or the measurement signal. It is a position measurement method that executes the correction process when it is determined that the invention is completed.

According to the seventh invention, when it is determined that the user has finished the locomotion, the measurement result of the real-time measurement process can be modified.

An eighth aspect of the invention is the position measuring method of the sixth invention, wherein the arithmetic processing unit determines that the user has stopped based on the measurement signal, and when the user determines that the user has stopped, the modification is made. It is a position measurement method that executes processing.

According to the eighth invention, when it is determined that the user has stopped, the measurement result of the real-time measurement process can be corrected.

A ninth aspect of the invention is the position measurement method of the sixth aspect, wherein the arithmetic processing unit executes the correction process based on the recorded data amount or the number of times of recording of the measurement result and the reference navigation information. It is a position measurement method.

According to the ninth invention, the correction process can be executed based on the measurement result of the real-time measurement process and the recorded data amount or the number of times of recording of the reference navigation information. As a result, for example, when the amount of recorded data exceeds a predetermined amount, or when the number of recordings exceeds a predetermined number, the correction process is executed, so that the data to be corrected is accumulated to some extent. Since the correction process can be executed with, the measurement result of the real-time measurement process can be corrected efficiently.

A tenth aspect of the present invention is the position measurement method of any one of the first to fourth aspects, wherein the user has a satellite positioning device attached to the predetermined portion or another portion, and the real-time measurement process is performed. By having the satellite positioning device perform a measurement operation at a given timing, control for acquiring reference navigation information is performed, and the measurement result of the real-time measurement process is recorded in association with the measurement time. A second arithmetic processing apparatus, which is separate from the arithmetic processing apparatus, includes recording the reference navigation information in association with the acquisition time, and the second arithmetic processing apparatus separates the arithmetic processing apparatus from the measurement result of the real-time measurement processing and the reference navigation information. It is a position measurement method that executes a correction process that corrects by using.

According to the tenth invention, the processing can be distributed such that the arithmetic processing unit executes the real-time measurement processing and the second arithmetic processing unit separate from the arithmetic processing unit executes the correction processing. .. In addition, the accuracy of the measured position information can be improved by the correction process.

The eleventh invention is the position measurement method of any one of the sixth to tenth inventions, and the real-time measurement process includes controlling a time interval for causing the satellite positioning device to perform a measurement operation. It is a position measurement method.

According to the eleventh invention, it is possible to control the time interval for causing the satellite positioning device to perform the measurement operation. As a result, it is possible to suppress the power consumption related to the positioning operation of the satellite positioning device.

A twelfth invention is the position measuring method of the eleventh invention, and controlling the time interval includes lengthening the time interval when the elapsed time from the start of measurement satisfies a predetermined condition. , Position measurement method.

According to the twelfth invention, the time interval for causing the satellite positioning device to perform the measurement operation can be lengthened when the elapsed time from the start of measurement satisfies a predetermined condition. For example, by setting the elapsed time to reach a predetermined time as a predetermined condition, it is possible to perform the positioning operation at a short time interval immediately after the start of positioning and to perform the positioning operation at a long time interval thereafter. .. Further, by setting the predetermined time as the predetermined condition stepwise, it is possible to gradually lengthen the time interval for performing the measurement operation with the passage of time.

The thirteenth invention is the position measurement method of the eleventh or twelfth invention, and controlling the time interval is a case where the satellite positioning device cannot determine the positioning position, or a predetermined time for determination. It is a position measurement method including shortening the time interval when the above time is taken.

According to the thirteenth invention, when the satellite positioning device fails in the positioning operation and the positioning position cannot be determined, or when the determination takes more than a predetermined time, the time interval for causing the satellite positioning device to perform the positioning operation is set. By shortening it, it is possible to prevent the acquisition time interval of reference navigation information from becoming long.

The fourteenth invention is the position measuring method of any one of the eleventh to thirteenth inventions, and controlling the time interval shortens the time interval when the yaw angle changes by a predetermined angle or more. It is a position measurement method including to do.

According to the fourteenth invention, the time interval for causing the satellite positioning device to perform the positioning operation can be shortened when the yaw angle based on the measurement signal of the inertial measurement unit changes by a predetermined angle or more. As a result, when the user's movement direction changes significantly, it becomes possible to acquire reference navigation information by performing positioning operations at short time intervals, and the measurement results of real-time measurement processing when the movement direction changes. Can be corrected more accurately.

The fifteenth invention is the position measurement method of any one of the sixth to fourteenth inventions, wherein the measurement result includes the position information and the yaw angle, and the reference navigation information includes reference. The position information and the reference yaw angle are included, and the correction process corrects the yaw angle included in the measurement result based on the reference yaw angle and corrects the position information included in the measurement result. , The position measurement method including the correction based on the corrected yaw angle.

According to the fifteenth invention, as a correction of the measurement result of the real-time measurement process, the yaw angle included in the measurement result is corrected based on the reference yaw angle included in the reference navigation information, and the measurement is performed based on the corrected yaw angle. The position information included in the result can be corrected.

The sixteenth invention is the position measurement method of the fifteenth invention, and the correction of the yaw angle is included in the measurement result based on the difference between the yaw angle included in the measurement result and the reference yaw angle. It is a position measurement method including correction of the yaw angle.

According to the sixteenth invention, in the correction of the measurement result of the real-time measurement process, the yaw angle included in the measurement result can be corrected based on the difference between the yaw angle included in the measurement result and the reference yaw angle. ..

The seventeenth invention is the position measurement method of the fifteenth or sixteenth invention, and the yaw angle correction is performed stepwise for each of a plurality of ranges in which the recording time range of the data included in the measurement result is different. It is a position measurement method to be performed.

According to the seventeenth invention, the yaw angle can be corrected efficiently by performing stepwise for each of a plurality of ranges having different recording time ranges, and the amount of calculation related to the yaw angle correction can be reduced, and eventually, the yaw angle can be corrected. This leads to a reduction in power consumption.

The eighteenth invention is the position measurement method of any one of the sixth to seventeenth inventions, and in the correction process, the position information is such that the locus connecting the position information passes through the reference position information. It is a position measurement method including correction.

According to the eighteenth invention, in the correction of the measurement result of the real-time measurement process, the position information is corrected so that the locus connecting the position information included in the measurement result passes through the reference position information included in the reference navigation information. can do.

A nineteenth invention is a position measurement method executed by an electronic device including an arithmetic processing unit, an inertial measurement unit, and a satellite positioning device, and the electronic device periodically moves with the movement or movement of a user. Attached to a predetermined portion of the user, the satellite positioning device acquires reference navigation information including reference position information in the first cycle while the user is moving or moving, and the arithmetic processing unit is used by the user. Real-time measurement processing that measures position information using the measurement signal of the inertial measurement unit in a second cycle shorter than the first cycle during movement or exercise, and the user during movement or exercise of the user. When it is determined that the user has interrupted or terminated the movement or movement based on the predetermined operation or the measurement signal, the reference navigation information is used to correct the measurement result of the real-time measurement process. It is a position measurement method characterized by performing correction processing and execution.

According to the nineteenth invention, the position information of the user is measured with high accuracy while suppressing the power consumption by the electronic device attached to the predetermined part of the user which moves periodically with the movement or movement of the user. Can be done. That is, the arithmetic processing unit provided in the electronic device executes real-time measurement processing for measuring the position information using the measurement signal of the inertial measurement unit provided in the electronic device, and the electronic device is provided when it is determined that the user has stopped. Using the reference navigation information acquired by the satellite positioning device, the correction process for correcting the measurement result of the real-time measurement process is executed. In addition, the reference navigation information is acquired by the satellite positioning device, which has a larger arithmetic processing load than the measurement of position information, in the first cycle, which is longer than the second cycle in which position information is measured, so that the entire electronic device can acquire the reference navigation information. Power consumption can be suppressed.

A twentieth invention is the position measurement method of the nineteenth invention, wherein the real-time measurement process estimates the speed of the user based on the signal characteristics of the measurement signal periodically appearing due to the locomotion. The position measurement method comprises calculating the yaw angle based on the measurement signal, and measuring the position information using the speed and the yaw angle.

According to the twentieth invention, in the real-time measurement process, the speed of the user can be estimated from the signal characteristics of the measurement signal that appears periodically by the periodic movement of the predetermined part of the user, and the speed of the user can be estimated based on the measurement signal. By calculating the yaw angle, the user's position information can be measured using this speed and the yaw angle.

The 21st invention is the position measurement method of the 19th or 20th invention, and the real-time measurement process records the measurement result of the real-time measurement process in association with the measurement time, and the reference navigation information. Is recorded in association with the acquisition time, and the correction process includes the recorded measurement result based on the reference navigation information at the acquisition time corresponding to the measurement time of the measurement result. It is a position measurement method characterized by including correction.

According to the twenty-first invention, in the correction process, the measurement result of the real-time measurement process can be corrected based on the reference navigation information acquired at the measurement time.

The 22nd invention is the position measuring method according to any one of 19th to 21st, wherein the satellite positioning device includes gradually lengthening the first cycle with the passage of time. The method.

According to the 22nd invention, it is possible to gradually lengthen the first cycle of causing the satellite positioning device to perform the positioning operation with the passage of time. As a result, power consumption can be reduced.

The 23rd invention is the position measurement method of the 22nd invention, in which the satellite positioning device cannot determine the positioning position, or when it takes a predetermined time or more to determine the positioning position. It is a position measurement method including shortening the first cycle.

According to the 23rd invention, when the satellite positioning device fails in the positioning operation and the positioning position cannot be determined, or when the determination takes more than a predetermined time, the satellite positioning device is made to perform the positioning operation. By shortening the cycle, it is possible to prevent the acquisition time interval of reference navigation information from becoming long.

A twelfth invention is an electronic device including an arithmetic processing device, an inertial measurement unit, and a satellite positioning device, wherein the electronic device is located at a predetermined portion of the user who periodically moves with the movement or movement of the user. The arithmetic processing unit is mounted, and the arithmetic processing unit executes real-time measurement processing for measuring position information using the measurement signal of the inertial measurement unit and correction processing for correcting the measurement result of the real-time measurement processing, and the real-time measurement is performed. The processing involves estimating the speed of the user based on the signal characteristics of the measurement signal periodically appearing due to the movement or movement, calculating the yaw angle based on the measurement signal, and the speed and the yaw. The position information is measured using the angle, the satellite positioning device is made to perform the measurement operation at a given timing, the control for acquiring the reference navigation information is performed, and the measurement result of the real-time measurement process is performed. Is recorded in association with the measurement time, and the reference navigation information is recorded in association with the acquisition time, and the correction process includes the recorded measurement using the reference navigation information. Electronic devices, including modifying the results.

According to the twenty-fourth invention, an electronic device is realized which is attached to a predetermined part of a user who periodically moves with the movement or movement of the user and measures the user's position information with high accuracy while suppressing power consumption. can do. That is, the arithmetic processing unit provided in the electronic device executes real-time measurement processing for measuring the position information using the measurement signal of the inertial measurement unit provided in the electronic device, and the electronic device is provided when it is determined that the user has stopped. Using the reference navigation information acquired by the satellite positioning device, the correction process for correcting the measurement result of the real-time measurement process is executed.

A twenty-fifth invention is a positioning system in which an electronic device including an arithmetic processing unit, an inertial measurement unit, and a satellite positioning device is connected by communication with a computer, and the electronic device is a movement of a user or a user. It is attached to a predetermined part of the user who moves periodically with movement, and the arithmetic processing unit executes a real-time measurement process of measuring position information using the measurement signal of the inertial measurement unit, and performs the real-time measurement process. Estimates the user's speed based on the signal characteristics of the measurement signal that periodically appears due to the movement or movement, calculates the yaw angle based on the measurement signal, and the speed and the yaw angle. By measuring the position information using the above, controlling the satellite positioning device to perform the measurement operation at a given timing, and controlling the acquisition of reference navigation information, and the measurement result of the real-time measurement process. The computer includes recording the reference navigation information in association with the measurement time and recording the reference navigation information in association with the acquisition time, and the computer records the recorded measurement result in the recorded reference navigation. It is a positioning system that executes correction processing that corrects using information.

According to the 25th invention, an electronic device attached to a predetermined part of a user who moves periodically with the movement or movement of the user and a computer are communicated and connected to measure the user's position information and suppress power consumption. However, it is possible to realize a positioning system that performs with high accuracy. That is, the arithmetic processing device of the electronic device executes real-time measurement processing for measuring the position information using the measurement signal of the inertial measurement unit of the electronic device, and the computer is the reference acquired by the satellite positioning device of the electronic device. Using the navigation information, execute the correction process to correct the measurement result of the real-time measurement process. As a result, the processing load can be distributed.

In the real-time measurement process, the user's speed can be estimated from the signal characteristics of the measurement signal that appears periodically by the periodic movement of the user's predetermined part, and the yaw angle is calculated based on the measurement signal. Therefore, the user's position information can be measured by using this speed and the yaw angle. In addition, the accuracy of the measured position information can be improved by the correction process of correcting the measurement result of the real-time measurement process.

A configuration example of an electronic device according to the first embodiment. Explanatory diagram of calculation of speed based on acceleration signal. Explanatory diagram of calculation of speed based on acceleration signal. Explanatory drawing of correction of INS yaw angle based on GPS yaw angle. Explanatory drawing of correction of INS yaw angle based on GPS yaw angle. Explanatory drawing of correction of INS yaw angle based on GPS yaw angle. Explanatory drawing of correction of INS yaw angle based on GPS yaw angle. Explanatory drawing of correction of INS yaw angle based on GPS yaw angle. Explanatory drawing of correction of INS yaw angle based on GPS yaw angle. Explanatory drawing of correction of INS position based on GPS position. Explanatory drawing of correction of INS position based on GPS position. The functional block diagram of the electronic device in 1st Embodiment. Flowchart of position information measurement processing. Flowchart of real-time measurement processing. Flow chart of correction process. A configuration example of the positioning system according to the second embodiment. The functional block diagram of the positioning system in 2nd Embodiment.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. It should be noted that the embodiments described below do not limit the present invention, and the embodiments to which the present invention can be applied are not limited to the following embodiments. Further, in the description of the drawings, the same elements are designated by the same reference numerals.

[First Embodiment]
First, a first embodiment to which the present invention is applied will be described.

<System configuration>
FIG. 1 is a configuration example of the electronic device 1 according to the first embodiment. The present embodiment will be described assuming that the electronic device 1 is a wristwatch-type electronic device called a so-called runner's watch that can be worn on the wrist or arm of the user 3. The mounting portion of the electronic device 1 is not limited to the wrist or arm, and may be a portion that periodically moves with the movement or movement of the user 3, and may be, for example, an ankle.

A display 12 for displaying the time, mileage, speed, etc. is provided on the upper surface of the housing 10 of the electronic device 1, and an operation switch for the user 3 to perform various operation inputs is provided on the side surface of the housing 10. A band 16 for attaching the electronic device 1 to the wrist or arm of the user 3 is provided. The housing 10 forms an airtight chamber, and contains a control board 18 electrically connected to a display 12, an operation switch 14 and the like, and a rechargeable battery 20 that supplies power to the control board 18 and the like.

The control board 18 includes a processor such as a CPU (Central Processing Unit) and an FPGA (Field Programmable Gate Array) as an arithmetic circuit, a main memory, a memory for measurement data, and an IMU (Inertial Measurement Unit) which is an inertial measurement unit. It is equipped with a GPS (Global Positioning System) module, which is a satellite positioning device, and a short-range wireless module. The electronic device 1 can also be called a computer in that it is equipped with a processor and can operate based on software.

The main memory is a storage medium for storing programs, initial setting data, processor calculation results, etc., and is composed of a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, and the like. The measurement data memory is a storage medium for storing measurement data by the IMU or GPS module, and is composed of data rewritable non-volatile memory such as flash memory, ferroelectric memory (FeRAM), and magnetoresistive memory (MRAM). To.

The IMU is a sensor unit having an acceleration sensor and a gyro sensor, and is an example of an inertial measurement unit. The accelerometer measures the acceleration (α _x , α _y , α _z ) in the three-dimensional Cartesian coordinate system (sensor coordinate system) associated with the accelerometer, and the gyro sensor is associated with the gyro sensor. Measure the angular velocity (ω _x , ω _y , ω _z ) in the three-dimensional Cartesian coordinate system (sensor coordinate system).

The GPS module receives GPS satellite signals transmitted from GPS satellites 5, and based on the received GPS satellite signals, positioning information which is reference navigation information including date and time, position coordinates expressed in latitude and longitude, speed, and attitude. This is an example of a satellite positioning system that measures. It should be noted that a satellite positioning device using other satellite positioning systems such as GLONASS (GLObal NAvigation Satellite System), GALIEO, and Beidou (BeiDou Navigation Satellite System) may be used instead of GPS.

The processor measures the position information of the user 3 by using the measurement data by the IMU and the GPS module. Specifically, while the user is moving, real-time measurement processing is performed to measure the position information of the user 3 using the measurement data by the IMU, and after the user 3 is stopped, the measurement data by the GPS module is used for real-time measurement. Perform correction processing to correct the position information measured by processing. In the present embodiment, it is assumed that the movement of the user 3 is the earth surface coordinates determined by the latitude and longitude, that is, the ground plane direction, and the position information does not include the altitude in order to make the explanation easy to understand. Of course, the altitude is included in the position information by calculating the altitude and including it in the position information, or by deriving the altitude from the earth surface coordinates by referring to the global geographic information defined by the three-dimensional coordinates and including it in the position information. Of course, it's okay.

<Principle>
The measurement of position information using the measurement data by the IMU and the GPS module will be described in detail.

(A) Real-time measurement processing In the real-time measurement processing, the position, speed, and moving distance of the user 3 are included every predetermined time Δt (for example, 1 second) using the input measurement signal of the IMU acceleration sensor. Measure position information. That is, the "real-time measurement process" is a process in which a user measures a predetermined parameter while using the arithmetic processing unit, and in the present embodiment, the user 3 wearing the electronic device 1 which is the arithmetic processing unit moves or moves. It is a process that periodically and continuously measures the position information during the exercise.

Specifically, as shown in FIGS. 2 and 3, the cycle of the arm swing motion of the user 3 is determined based on the measurement signal of the acceleration sensor. 2 and 3 show an example of the waveform of the measurement signal of the accelerometer with the horizontal axis as the time. However, the accelerometer outputs a measurement signal indicating the value of each axis component (α _x , α _y , α _z ) of the three axes (X, Y, Z axes), but in FIGS. 2 and 3, each axis component is output. The size of the combined vector, that is, the size of the acceleration, is used as the measured value on the vertical axis. In the present embodiment, since the part where the electronic device 1 is attached is the arm, as shown in FIG. 2, the acceleration changes periodically due to the movement of the user 3 or the arm swinging motion accompanying the movement, and the cycle of the acceleration. Changes in the target value appear as measured values.

The low-pass filter processing is performed on this acceleration signal to obtain the post-filter acceleration signal from which the high-frequency component which is a noise component is removed, and further, the first-order differential processing is performed on the post-filter acceleration signal to obtain the time of the post-filter acceleration signal. Find the acceleration signal that represents the change. Next, for the signal waveform of this acceleration signal, a zero cross point (point where the value becomes zero) 30 that changes from a negative value to a positive value before and after that is detected, and a period between two consecutive zero cross points 30 is set. , It is one cycle of the arm swinging motion of the user 3. Then, the point on the signal waveform of the post-filtered acceleration signal at the time of each zero cross point 30 is set as the reference point 32 of the cycle of the arm swing operation.

Subsequently, as shown in FIG. 3, in the signal waveform of the post-filter acceleration signal, the difference from the value of the reference point 32 of each cycle to the peak value immediately after that is obtained and used as the amplitude _Amp of the post-filter acceleration signal. .. Then, the speed V is obtained according to the estimation formula shown in the following formula (1).

式（１）において、ａ_１は係数であり、例えば、０．１～０．２程度の値に定められる。

In the formula (1), a ₁ is a coefficient, and is set to a value of, for example, about 0.1 to 0.2.

In the real-time measurement process, the position information is measured every predetermined time Δt, and the speed V at a certain measurement time t is the speed V obtained by using the amplitude _Amp for one cycle immediately before the measurement time t. ..

The coefficient a1 of the estimation formula ( ₁ ) of the speed V is corrected by the measurement data obtained by the GPS module. Specifically, the coefficient a ₁ is updated to the "coefficient a _1n " calculated by the following equation (2) using the speed V _g (reference speed) included in the measurement data by the GPS module.

式（２）において、Ｂは定数であり、例えば、Ｂ＝０．７、に設定することができる。勿論、０．７ではなく、Ｂの値は、０．６や０．８等とすることもできるが、０より大きく、１未満の数である必要がある。好適には、０．５以上１．０未満である。

In the equation (2), B is a constant and can be set to, for example, B = 0.7. Of course, the value of B instead of 0.7 can be 0.6, 0.8, or the like, but it must be a number greater than 0 and less than 1. Preferably, it is 0.5 or more and less than 1.0.

Further, the correction of the coefficient a1 is performed _every time the GPS module measures the positioning information (positioning operation) and new positioning information is obtained. The time interval Δt _g in which the GPS module performs the positioning operation is determined to be longer than the time interval Δt in which the position information is measured in the real-time measurement process. Therefore, the coefficient a1 is corrected _once for each measurement of the position information a plurality of times in the real-time measurement process.

Subsequently, using the speed V thus obtained and the yaw angle ψ calculated from the angular velocity (ω _x , ω _y , ω _z ) measured by the IMU gyro sensor, the following equation (3) The velocity components V _x , V _y , the position components P _x , P _y , and the moving distance D are calculated according to the calculation formula shown in 1. The velocity components V _x , V _y , and the position components P _x , P _y are the X and Y axis direction components of the velocity and the position in the ground plane, respectively. Here, "velocity" has a meaning including both direction and speed, and can also be called a velocity vector. "Speed" is the distance traveled per unit time and is the speed. The X and Y axes can be determined, for example, as a direction along the north-south direction in the X-axis direction and the east-west direction in the Y-axis direction. Therefore, the "velocity component V _x " means the speed in the X-axis direction, and the "velocity component V _y " means the speed in the Y-axis direction. Therefore, it can be said that "speed V" means the magnitude of "speed".

式（３）において、“Ｆ_ｃ，Ｆ_ｓ”は、それぞれ、ヨー角ψの、Ｘ軸方向成分（＝ｓｉｎψ）、及び、Ｙ軸方向成分（＝ｃｏｓψ）に対して、ローパスフィルター処理を行った値である。“ｄｔ”は、リアルタイム計測処理において位置情報の計測を行う時間間隔Δｔに相当する時間である。“Ｐ_ｘ０，Ｐ_ｙ０，Ｄ_０”は、それぞれ、直前（つまり、時間Δｔだけ過去の計測時刻）に計測した位置情報に含まれる、位置成分Ｐ_ｘ，Ｐ_ｙ、移動距離Ｄ、である。

In the formula (3), “F _c , F _s ” is subjected to low-pass filter processing on the X-axis direction component (= sin ψ) and the Y-axis direction component (= cos ψ) of the yaw angle ψ, respectively. Value. “Dt” is a time corresponding to the time interval Δt for measuring the position information in the real-time measurement process. “P _x 0, P _y 0, D ₀ ” are the position components P _x , P _y , and the moving distance D, which are included in the position information measured immediately before (that is, the past measurement time by the time Δt), respectively.

In this way, in the real-time measurement process, the velocity components V _x , V _y , and the position component P _x , at each measurement time t for each predetermined time Δt, calculated using the measurement data (acceleration and angular velocity) of the IMU. _Py , yaw angle, and travel distance D are collectively referred to as INS (Inertial Navigation System) log data.

(B) Correction processing The "correction processing" is performed using the parameters measured by the real-time measurement processing after the real-time measurement processing using the arithmetic processing unit is completed or when the real-time measurement processing is not executed. It is a process, and in the present embodiment, it is a process of correcting the INS log data which is the measurement result of the real-time measurement process by using the measurement data by the GPS module.

The GPS module performs positioning operation every Δt _g for a predetermined time to acquire positioning information which is reference navigation information, and the position, speed, and position included in the positioning information acquired at each positioning time for each predetermined time Δt _g . , Yaw angle ψ is collectively referred to as GPS log data.

Specifically, in the correction process, first, the "yaw angle" (hereinafter referred to as "INS yaw angle") obtained from the angular velocity measured by the gyro sensor is included in the GPS log data as the yaw angle (reference yaw angle). (Hereinafter referred to as "GPS yaw angle"), the initial correction (Initial correction), the overall correction (Global correction), and the local correction (Local correction) are performed three times. Then, the position, speed, and moving distance are calculated again using the corrected yaw angle. Then, the calculated position is used as reference position information using the position information included in the GPS log data (hereinafter referred to as "GPS position"), and the final correction (hereinafter also referred to as "position correction") is performed using this GPS position. conduct. Hereinafter, each procedure of this correction process will be described in detail.

As shown in FIGS. 4 to 6, the initial correction targets a part of the measurement period in which the real-time measurement process is performed (for example, the period of about the first few minutes), and the INS yaw angle and GPS yaw in this target period. A correction formula based on the difference from the angle is calculated, and this correction formula is used to correct all INS yaw angles in the measurement period.

I will explain in detail step by step. FIG. 4 shows a line graph in which the waveform of the INS yaw angle at each measurement time t of the real-time measurement process and the GPS yaw angle at each positioning time t _g by the GPS module are connected in chronological order with the horizontal axis as the time, and the GPS module. A line graph in which the INS yaw angles at each positioning time t _g are connected in chronological order is shown. In FIG. 4, the target period is set to about 350 seconds (a little less than 6 minutes), and the interval of each measurement time t in the real-time measurement process is set to 1 second. Further, the case where the interval of each positioning time t _g by the GPS module is set to 10 seconds or more, the interval is gradually increased, and 1 minute (60 seconds) is set after 120 seconds have elapsed is illustrated.

In FIG. 4, as shown by the fine solid line of the double-headed arrow in the vertical direction, the difference W11 between the INS yaw angle and the GPS yaw angle at each positioning time _tg is obtained. The polygonal line connecting the yaw angle difference W11 is shown in FIG. 5 as a plot diagram of the yaw angle difference _W11 obtained at each positioning time tg. At this time, for the positioning time _tg in which the magnitude relationship between the INS yaw angle and the GPS yaw angle is reversed, the sign inversion (roll) is performed by subtracting or adding 360 degrees from the value of the difference W11. Out) sign normalization is performed. Then, the first-order polynomial is fitted to the yaw angle difference W12 of each positioning time after sign normalization, and the initial correction formula C1 which is an approximate formula of the first-order polynomial representing the relationship between the time and the difference is calculated.

Subsequently, this initial correction formula C1 is used to correct all INS yaw angles during the measurement period. That is, the INS yaw angle after the initial correction is obtained by adding the difference of the measurement time t obtained from the initial correction formula C1 to the INS yaw angle of each measurement time t as a correction value.

FIG. 6 shows the time-series changes of the INS yaw angle, the GPS yaw angle, and the yaw angle after the initial correction. It can be seen that the INS yaw angle is corrected so as to approach the GPS yaw angle by the initial correction, and the yaw angle after the initial correction is obtained.

Next to the initial correction is the overall correction. In the overall correction, a correction formula based on the difference between the initial corrected INS yaw angle and the GPS yaw angle in the entire measurement period of the real-time measurement process is calculated, and the correction formula is used to further increase the initial corrected INS yaw angle. to correct.

I will explain in detail step by step. 7 and 8 are diagrams showing an example of total correction. First, as shown in FIG. 7, the difference _W21 between the initial corrected INS yaw angle and the GPS yaw angle at each positioning time tg by the GPS module is obtained. At this time, for the time when the magnitude relationship between the initial corrected INS yaw angle and the GPS yaw angle is reversed, the sign inversion (roll) is performed by subtracting or adding 360 degrees from the difference value. Out) sign normalization is performed. The difference between the yaw angles at each positioning time after code normalization is the difference W22.

Next, the fitting process of the quadratic polynomial is performed on the value of the difference _W22 at each of these positioning times tg to obtain the overall correction formula C3 which is an approximate expression of the quadratic polynomial representing the relationship between the time and the difference. FIG. 8 is a diagram showing the calculation of the overall correction formula C3. In FIG. 8, the difference W23 is the same as the difference W22 in FIG. 7, but different values are taken because the yaw angle data that is the basis of the calculation is different. As shown in FIG. 8, the total correction formula 3 can be calculated by performing the fitting process of the quadratic polynomial for each value of the difference W23 (difference W22 in FIG. 7). Using this total correction formula C3, the INS yaw angle after all initial corrections in the measurement period is corrected (total correction). That is, as in the initial correction, the difference corresponding to the measurement time t obtained from the total correction formula C3 is added as a correction value to the INS yaw angle after the initial correction at each measurement time t, so that the total correction is performed. Find the INS yaw angle.

Next to the overall correction is the local correction. In the local correction, the yaw angle after the whole correction is corrected so that the yaw angle at each positioning time _tg in the yaw angle after the whole correction matches the GPS yaw angle. FIG. 9 is a diagram showing an example of local correction, in which the horizontal axis is the time, the overall corrected INS yaw angle at each measurement time t of the measurement period, the GPS yaw angle at each positioning time _tg , and the local area. The INS yaw angle after the local correction after the correction is shown. In the local correction, first, among the total corrected INS yaw angles, a correction value for making the total corrected INS yaw angle corresponding to each positioning time _tg a GPS yaw angle is obtained. Then, the correction value at each measurement time t is obtained by complementing and obtaining the correction value between the consecutive positioning times t _g before and after. By adding the obtained correction value to the INS yaw angle after the total correction for each of the corresponding measurement times t, the INS yaw angle after the total correction is corrected (local correction), and the INS yaw angle after the local correction is obtained.

In this way, when the INS yaw angle is corrected (initial correction, overall correction, and local correction) at each measurement time t, the calculation shown in the equation (3) is performed using the INS yaw angle after the local correction. According to the equation, the velocity components V _x , V _y , the position components P _x , P _y , and the travel distance D are recalculated. Then, as shown in FIG. 10, the recalculated position components P _x and P _y are corrected (position correction) using the position included in the GPS log data (hereinafter referred to as “GPS position”). This position correction is the final correction of the correction process.

In FIG. 10, the horizontal axis is the position component P _x , the vertical axis is the position component P _y , and the position determined by the position components P _x , P _y at each measurement time recalculated using the locally corrected INS yaw angle ( Hereinafter, this position is referred to as "INS position"), and the movement locus is shown by connecting them in chronological order. In the position correction, the INS position corresponding to each positioning time t _g is matched with the GPS position, and the INS position at each measurement time t is corrected so that the time-series change of the INS position at each measurement time t becomes smooth. do. That is, the movement locus connecting the INS position after the position correction in chronological order is corrected so as to pass through the GPS position, and is corrected so as to change along with the time-series change of the INS position before the original correction. It becomes the trajectory that was done. Here, "correction to pass the GPS position" means not only passing the GPS position but also passing in the vicinity of the GPS position. For example, when a method of correcting a movement trajectory by using a GPS position like a control point such as a B-spline curve or a Bezier curve is adopted, it does not necessarily pass through the GPS position but may pass near the GPS position. Is. In the present embodiment, the INS position (position component P _x , _Py ) corresponding to each positioning time t _g is changed so as to match the GPS position of the positioning time t _g , and the positioning time t _g is changed. According to the changed INS position, the INS position at each measurement time t other than the positioning time t _g is corrected by changing so as to interpolate according to the relationship between the INS positions at the previous and next measurement times t.

Specifically, for example, when correcting the INS position at each measurement time between certain continuous positioning times t _m and t _n , first, from the GPS position P _gm at the positioning time t _m , the GPS at the positioning time t _n When the start point of the vector (GPS position vector) toward the position P _gn is matched with the start point of the vector (INS position vector) from the INS position P _m at the positioning time _{tm to the INS position P n at} the positioning time t _n . The difference dθ between the angles of both vectors and the difference dR of the magnitudes are obtained. Next, the correction speed dV applied between the positioning times _tm and tun is calculated according to the calculation formula shown in the formula (4).

Subsequently, the correction speed dV is added to the speed V at each measurement time t between the positioning times t _m and t _n to correct the speed V, and further, the speed V at each corrected measurement time t is used to obtain the equation (3). The position components P _x and P _y at each measurement time t are calculated again according to the calculation formula shown in 1. The speed V at the measurement time t is a value obtained from the measurement signal (acceleration signal) of the acceleration sensor 202 according to the equation (1) in the real-time measurement process (see FIG. 2).

Then, the INS positions P _m and P _n at the measurement times t _m and t _n are changed to the GPS positions P _g m and P _g n at the measurement times t _m and t _n , respectively. After that, for each measurement time t between the positioning times t _m and t _n , from the changed INS position P _m to the INS position P _t defined by the recalculated position components P _x and P _y at the measurement time t. Find the vector to go to. The position of the end point obtained by rotating this vector so as to approach the GPS position vector by the angle difference dθ is changed as the position components P _x and P _y at the measurement time t.

FIG. 11 shows the locus of the INS position after the position correction with respect to the INS position at each measurement time between the positioning times t _m and t _n shown in FIG.

<Functional configuration>
FIG. 12 is a block diagram showing a functional configuration of the electronic device 1. As shown in FIG. 12, the electronic device 1 includes a GPS module 100 which is a satellite positioning device, an IMU 200 which is an inertial measurement device, and an arithmetic processing unit 400.

The GPS module 100 is a satellite positioning device that receives GPS satellite signals, and is based on navigation messages such as orbit information (Ephemeris and Armanac) of GPS satellites that are carried by superimposing on GPS satellite signals received by GPS antennas. Then, the positioning information which is the reference navigation information including the position, speed, and attitude of the GPS module 100 is measured.

The IMU 200 is a sensor unit having an acceleration sensor 202 and a gyro sensor 204. The acceleration sensor 202 measures the acceleration (α _x , α _y , α _z ) of each axis of the three-dimensional Cartesian coordinate system (local coordinate system) associated with the acceleration sensor 202. The gyro sensor 204 measures the angular velocities (ω _x , ω _y , ω _z ) of each axis of the three-dimensional Cartesian coordinate system (local coordinate system) associated with the gyro sensor 204.

The arithmetic processing unit 400 has an operation unit 402, a display unit 404, a sound output unit 406, a communication unit 408, a clock unit 410, a processing unit 500, and a storage unit 600 as functional units.

The operation unit 402 is an input device composed of a touch panel, a button switch, or the like, and outputs an operation signal corresponding to the user's operation to the processing unit 500. The operation switch 14 in FIG. 1 corresponds to this.

The display unit 404 is a display device composed of a touch panel, an LCD (Liquid Crystal Display), or the like, and performs various displays based on the display signal from the processing unit 500. The display 12 of FIG. 1 corresponds to this.

The sound output unit 406 is a sound output device composed of a speaker or the like, and outputs various sounds based on the sound signal from the processing unit 500.

The communication unit 408 is a wireless communication device for realizing wireless communication such as a wireless LAN (Local Area Network) and Bluetooth (registered trademark), and performs wireless communication with an external device. The wireless communication module mounted on the control board 18 of FIG. 1 corresponds to this.

The clock unit 410 is an internal clock, which is composed of an oscillation circuit having a crystal oscillator or the like, and measures the current time, the elapsed time from the designated timing, and the like.

The processing unit 500 includes a processor such as a CPU, a GPU (Graphics Processing Unit), an FPGA (Field Programmable Gate Array), an ASIC (Application Specific Integrated Circuit), an IC (Integrated Circuit), and other electronic components such as a memory. Each unit of the arithmetic processing unit 400 is collectively controlled according to various programs such as a system program stored in the storage unit 600. The CPU mounted on the control board 18 of FIG. 1 corresponds to this. Further, the processing unit 500 executes the position information measurement program 602 stored in the storage unit 600 to form an action type determination unit 502, a real-time measurement processing unit 504, a correction processing unit 506, and a positioning control unit 508. , It will function as a speed estimation type correction unit 510. It should be noted that each unit constituting the processing unit 500 may be realized by hardware such as a dedicated module circuit.

The action type determination unit 502 determines the action type of the user 3 based on the measurement signal of the IMU 200. Specifically, if the period can be detected for the acceleration signal of the acceleration sensor 202 and the amplitude _Amp is equal to or higher than a predetermined value, it is determined that the user 3 is moving (moving). If not, the user 3 is determined to be stopped. Further, when the transition from the stop to the movement is performed, it is determined that the movement movement has started, and when the transition from the movement to the stop is performed, it is determined that the movement movement has been completed. Alternatively, the action type such as the start, stop, and end of the movement of the user 3 may be determined by a predetermined operation input from the operation unit 402. Here, the movement of the user 3 may be walking or biking in addition to running. In the case of a bicycle, it is preferable to attach the electronic device 1 to the ankle, which is a part where periodic exercise is performed.

The real-time measurement processing unit 504 executes real-time measurement processing for measuring position information using the measurement signal of the IMU 200, which is an inertial measurement unit. That is, as a real-time measurement process, the speed V of the user 3 is calculated according to the estimation formula shown in the formula (1) based on the acceleration signal of the acceleration sensor 202 of the IMU 200 at a predetermined time interval Δt. Next, using this speed V and the yaw angle ψ calculated from the angular velocity (ωx, ωy, ωz) measured by the gyro sensor 204 of the IMU200, the velocity component is according to the calculation formula shown in the formula (3). V _x , V _y , the position component P _x , P _y , and the moving distance D are calculated (see FIGS. 2 and 3).

The speed estimation formula used for calculating the speed V is stored as the speed estimation formula information 604. _The speed estimation formula information 604 includes the value of the coefficient a1 in the speed estimation formula, and the coefficient _a1 is corrected by the speed estimation formula correction unit 510. Further, the calculation formulas used for calculating the velocity components V _x , V _y , the position components P _x , P _y , and the moving distance D are stored as INS calculation formula information 606.

Then, the real-time measurement processing unit 504 sets the calculated speed V, speed component V _x , V _y , position component P _x , P _y , and moving distance D as the measurement result of the real-time measurement processing, and associates them with the measurement time. Then, it is stored and stored as INS log data 612.

The correction processing unit 506 corrects the measurement result of the real-time measurement processing by the real-time measurement processing unit 504 by using the GPS log data 610 which is the reference navigation information acquired by the GPS module 100 which is the satellite positioning device by performing the positioning operation. Execute the correction process. The correction process is executed when the action type determination unit 502 determines that the user 3 has stopped or the locomotion has ended.

In the correction process, the yaw angle (INS yaw angle) obtained from the angular velocity measured by the gyro sensor 204 is initially corrected, totally corrected, and the yaw angle (GPS yaw angle) included in the GPS log data 610 is used. , Perform three corrections of local correction. After that, the position, speed, and moving distance are calculated again using the corrected yaw angle, and then the calculated position is corrected (position correction) using the position (GPS position) included in the GPS log data 610. )do.

In the initial correction, the initial correction formula C1 is calculated based on the differences W11 and W12 between the INS yaw angle ψ and the GPS yaw angle in a predetermined period from the start of movement of the user 3, and the measurement period is calculated using this initial correction formula C1. Corrects all INS yaw angles in. Next, in the overall correction, the overall correction formula C3 is calculated based on the difference W23 between the INS yaw angle and the GPS yaw angle after the initial correction in the measurement period, and all the initial corrections in the measurement period are used using this overall correction formula C3. After that, the INS yaw angle is corrected. Subsequently, in the local correction, all the corrected INS yaw angles in the measurement period are corrected so that the INS yaw angle after the total correction at each positioning time matches the GPS yaw angle. Then, in the position correction, the position components Px and Py, which are the INS positions, are calculated using the INS yaw angle after the local correction, and all the INS in the measurement period so that the INS position at each positioning time matches the GPS position. Correct the position.

The speed V, the speed components V _x , V _y , the position components P _x , P _y , and the moving distance D corrected by the correction processing unit 506 for each measurement time t are stored as the correction position information 614.

The positioning control unit 508 controls the positioning operation performed by the GPS module 100, which is a satellite positioning device. Specifically, when the action type determination unit 502 determines that the movement of the user 3 has started, the GPS module 100 is controlled to perform the positioning operation intermittently at predetermined time intervals to perform positioning. When it is started and it is determined that the locomotion is stopped, the positioning is terminated. The time interval (first cycle) for performing this positioning operation is set longer than the time interval Δt (second cycle) for measuring the position information in the real-time measurement process.

Further, the positioning control unit 508 can change the time interval for causing the GPS module 100 to perform the positioning operation. Specifically, when the elapsed time from the start of positioning by the GPS module 100 satisfies a predetermined condition, the time interval of the positioning operation is controlled to be long. For example, by setting the elapsed time to be a predetermined time or longer as a predetermined condition, the positioning operation is performed relatively frequently immediately after the start of positioning by the GPS module 100, but after a while, the positioning operation is performed frequently. Can be lowered and the time interval (first final stage) for performing the positioning operation can be lengthened. Further, by setting a predetermined time as a predetermined condition stepwise, it is possible to gradually lengthen the time interval (first cycle) of the positioning operation with the passage of time.

Further, when the GPS module 100 fails in positioning and the positioning position cannot be determined, or when it takes a predetermined time or more to determine the positioning position, a predetermined short time interval, an initial time interval, or the shortest time interval is required. The time interval of the positioning operation may be shortened, such as changing to the time interval. Alternatively, when the yaw angle ψ obtained from the angular velocity (ωx, ω _y , ω _z ) measured by the gyro sensor 204 changes by a predetermined angle or more, the time interval of the positioning operation may be shortened. As a situation where the yaw angle ψ changes significantly, for example, there is a situation where the user 3 turns a corner.

Then, the positioning control unit 508 stores and stores the position, speed, and attitude acquired by causing the GPS module 100 to perform the positioning operation as GPS log data 610 in association with the acquisition time as reference navigation information. ..

The speed estimation type correction unit 510 corrects the coefficient a1 in the estimation formula of the user's speed V shown in the formula ( ₁ ). This speed estimation type correction is performed when the GPS module 100 performs a positioning operation and new positioning information is obtained. Specifically, the coefficient a ₁ is updated to the "coefficient a _1n " calculated according to the equation (2) by using the speed V _g included in the obtained positioning information.

The storage unit 600 is a storage device composed of a ROM, a RAM, or the like, and the processing unit 500 stores programs and data for realizing various functions of the electronic device 1 and is used as a work area of the processing unit 500. , The calculation result of the processing unit 500 and the input data from the operation unit 402 and the communication unit 408 are temporarily stored. The main memory and the memory for measurement data mounted on the control board 18 of FIG. 1 correspond to this. Further, in the storage unit 600, the position information measurement program 602, the speed estimation type information 604, the INS calculation type information 606, the IMU log data 608, the GPS log data 610, the INS log data 612, and the correction position information 614 and is stored.

The position information measurement program 602 is a program for realizing a function of measuring the position information of the user 3 who wears the electronic device 1 by reading and executing the position information measurement program 602. When each functional unit in the processing unit 500 is realized by hardware such as an electronic circuit, a part of the program for realizing the functional unit can be omitted.

The IMU log data 608 is data that stores and stores the measured values of the acceleration sensor 202 and the gyro sensor 204 of the IMU 200, and is the acceleration that is the measured value of the acceleration sensor 202 at each measurement time t of the position information by the real-time measurement processing unit 504. It is the data associated with (α _x , α _y , α _z ) and the angular velocity (ω _x , ω _y , ω _z ) which is the measured value of the gyro sensor 204.

<Processing flow>
FIG. 13 is a flowchart illustrating a flow of position information measurement processing in the electronic device 1. Prior to the execution of this process, it is assumed that the electronic device 1 is attached to the wrist or arm of the user 3.

First, the action type determination unit 502 starts determining the action type such as whether the user 3 is moving or stopped, and the start and end of the movement movement of the user 3, based on the measurement signal of the IMU 200 (step S1). .. Then, if it is determined that the user 3 has started the locomotion (step S3: YES), the real-time measurement processing unit 504 starts executing the real-time measurement processing (see FIG. 14) (step S5).

After that, if it is determined that the user 3 has finished the locomotion (step S7: YES), the real-time measurement processing unit 504 ends the running real-time measurement processing (step S9). Subsequently, the correction processing unit 506 executes the correction processing (see FIG. 15) (step S11). When the above processing is performed, the position information measurement processing is completed.

FIG. 14 is a flowchart illustrating a flow of real-time measurement processing. In the real-time measurement processing, the real-time measurement processing unit 504 repeatedly executes the processing of the loop A every predetermined time Δt (for example, 1 second).

That is, the speed V of the user 3 is calculated using the speed estimation formula shown in the formula (1) based on the measurement signal (acceleration signal) of the acceleration sensor 202 (step S31). Further, the yaw angle ψ is calculated based on the angular velocity (ω _x , ω _y , ω _z ) which is the measured value of the gyro sensor 204 (step S33). Next, based on the calculated velocity V and the yaw angle ψ, the velocity components V _x , V _y , the position components P _x , P _y , and the moving distance D are calculated using the calculation formula shown in the equation (3). Calculate (step S35). Then, the calculated velocity components V _x , V _y , the position components P _x , P _y , and the moving distance D are used as measurement information, and the current time is used as the measurement time in association with this and added to the INS log data 612. And record (step S37). Further, the measurement result is displayed by displaying the calculated speed V, the moving distance D, and the like on the display unit 404 (step S39).

After that, if new positioning information is acquired by the positioning operation of the GPS module 100 (step S41: YES), the speed estimation type correction unit 510 uses the speed Vg (reference speed) included in the acquired positioning information. Then, the coefficient _a1 in the speed estimation formula is corrected (step S43). The processing of loop A is performed in this way.

FIG. 15 is a flowchart illustrating the flow of the correction process. In the correction process, the correction processing unit 506 first targets a predetermined period from the start of movement of the user 3, and the initial correction formula C1 is based on the difference W11 between the GPS yaw angle and the INS yaw angle of each positioning time in the target period. (Step S51), and using this initial correction formula C1, initial correction is performed to correct the INS yaw angle at each measurement time in the measurement period (step S53).

Next, the difference W21 between the GPS yaw angle of each positioning time in the target period and the INS yaw angle after the initial correction is obtained for the entire measurement period, and the overall correction formula C3 is calculated based on this difference W21. (Step S55). Then, using this total correction formula C3, total correction is performed to correct the INS yaw angle after the initial correction at each measurement time in the measurement period (step S57). Subsequently, local correction is performed to correct the overall corrected INS yaw angle at each measurement time of the measurement period so that the overall corrected INS yaw angle at each positioning time matches the GPS yaw angle (step S59). ).

Then, based on the locally corrected INS yaw angle, the velocity components V _x , V _y , the position components P _x , P _y , and the moving distance D are recalculated using the calculation formula shown in the formula (3). (Step S61). Then, position correction is performed to correct the recalculated INS position at each measurement time in the measurement period so that the INS position at each positioning time matches the GPS position (step S63).

Then, the speed V, the velocity components V _x , V _y , and the position components Px, Py at each measurement time t recalculated and corrected are recorded as the corrected position information 614 (step S65). When the above processing is performed, the correction processing is completed.

[Second Embodiment]
Next, a second embodiment to which the present invention is applied will be described. The second embodiment is different from the first embodiment in that the correction process executed by the electronic device in the first embodiment is executed by a separate computer capable of communicating with the electronic device. In the following second embodiment, the same elements as those of the above-mentioned first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted or simplified.

<System configuration>
FIG. 16 is a configuration diagram of the positioning system 7 according to the second embodiment. As shown in FIG. 16, the positioning system 7 is configured by connecting the electronic device 1B and the computer 9 by communication.

The electronic device 1B is a device similar to the electronic device 1 in the first embodiment, and is a wristwatch-type electronic device that can be worn on the wrist or arm of the user 3 and is a so-called runner's watch.

The computer 9 can be realized by, for example, a notebook computer, a tablet computer, or the like, in addition to the personal computer and smartphone shown in FIG. Further, the computer 9 may be realized as a computer system in which a plurality of computers are communicated and connected. When the computer 9 is realized as a portable device such as a smartphone, the electronic device 1B is attached to the lower arm (wrist) of the user 3, and the computer 9 is attached to the upper arm or stored in a mobile bag or the like for carrying. By doing so, it is possible to maintain a state in which the electronic device 1B and the computer 9 are always connected by wireless communication.

<Overview>
In the second embodiment, as in the first embodiment, the electronic device 1B is attached to a predetermined portion that periodically moves with the movement or movement of the user 3, such as the arm or wrist of the user 3. The electronic device 1B performs real-time measurement processing for measuring the position information of the user 3 while the user 3 is moving. Then, after the movement of the user 3 is completed, the electronic device 1B is removed from the user 3, and for example, by operating a predetermined operation switch 14 by the user 3, a short-range wireless communication with the computer 9 owned by the user 3 is performed. Is started, and data such as IMU log data 608, GPS log data 610, and INS log data 612 recorded in the main memory mounted on the control board 18 and the measurement data memory are transmitted to the computer 9. Then, the computer 9 performs a correction process based on these received data and displays the result of the correction process.

Although the computer 9 is shown in FIG. 16 as if it were owned by the user 3, a server system operated by a business operator that provides various data management services related to exercise using the electronic device 1B. The electronic device 1B and the computer 9 may be connected to each other via the Internet.

<Functional configuration>
FIG. 17 is a functional configuration diagram of the positioning system 7 according to the second embodiment. The electronic device 1B differs from the electronic device 1 (see FIG. 12) in the first embodiment in that the processing unit 500B of the arithmetic processing unit 400B does not include the correction processing unit 506 as a functional unit, and the storage unit 900 Does not store the correction position information 614 generated by the correction processing unit 506.

The computer 9 has an operation unit 702, a display unit 704, a sound main unit 706, a communication unit 708, a clock unit 710, a processing unit 800, and a storage unit 900. The processing unit 800 has a correction processing unit 506 as a functional unit. The storage unit 900 stores the correction processing program 902, the INS calculation formula information 606, the IMU log data 906, the GPS log data 908, the INS log data 910, and the correction position information 614.

The correction processing program 902 is a program for executing the correction processing (see FIG. 15) by the processing unit 800 reading and executing the correction processing program 902.

The IMU log data 906, GPS log data 908, and INS log data 910 are used in the IMU log data 608, GPS log data 610, and INS log data 612 received from the electronic device 1 by data communication via the communication unit 708. Corresponding data.

The processing flow executed by the positioning system 7 in the second embodiment is the same as the processing flow described with reference to FIGS. 13 to 15. In the first embodiment, the execution subject is only the electronic device 1, but in the second embodiment, the electronic device 1B and the computer 9 are used, and there is only a difference in the distributed processing in which the roles are divided according to the processing. ..

[Action effect]
Although the two embodiments have been described above, according to the present embodiment, the measurement of the position information using the measurement signal of the inertial measurement unit can be performed with high accuracy while suppressing the power consumption. That is, while the user 3 is moving, a real-time measurement process for measuring the position information of the user 3 is performed using the measurement signal of the IMU200, which is an inertial measurement unit, and after the user 3 is stopped, the measurement result of the real-time measurement process is transmitted to the satellite. It can be corrected by using the positioning information which is the reference navigation information acquired by the positioning operation by the GPS module 100 which is the positioning device.

GPS positioning is highly accurate but consumes relatively large power, so while the user 3 is moving, position information is measured using the measurement signal of the IMU 200, and the positioning operation by the GPS module 100 is the position information in the real-time measurement process. By performing the measurement in a cycle longer than the measurement cycle and correcting the measurement result of the real-time measurement process using the acquired positioning information, the position information is measured with high accuracy and the power consumption is reduced as a whole. ..

In addition, the measurement of position information in the real-time measurement process is realized by a method different from the conventional inertial navigation calculation by utilizing the relationship between the movement speed of the user 3 and the arm swing motion. , Further reduction of power consumption is realized. In particular, the measurement of the position where the user 3 moves is divided into the speed and the yaw angle, which is a peculiar process to reduce the power consumption.

[Modification example]
It should be noted that the applicable embodiment of the present invention is not limited to the above-described embodiment, and of course, it can be appropriately changed without departing from the spirit of the present invention.

(A) Calculation and display of lap time For example, a predetermined unit distance is determined based on the movement distance D at each measurement time calculated in the real-time measurement process while the user 3 is moving and the elapsed time from the start of the movement movement. The time required for the movement (so-called lap time) may be calculated, recorded and displayed.

(B) Execution timing of the correction process Further, the correction process may be executed not only during the stop of the user 3 or after the end of the locomotion, but also during the movement of the user 3. For example, the amount of recorded data or the number of recordings related to the recording of the position information which is the measurement result of the real-time measurement process in the INS log data 612 and the recording of the positioning information acquired by the positioning operation of the GPS module in the GPS log data 610. Based on this, it is possible to determine whether or not to execute the correction process and execute the correction process. Specifically, when the amount of recorded data or the number of times of recording reaches a predetermined amount of data or a predetermined number of times, the correction process can be executed. As a result, the correction process can be executed with the data to be corrected accumulated to some extent, so that the correction accuracy of the measurement result of the real-time measurement process can be improved.

1 ... electronic equipment, 3 ... user, 5 ... GPS satellite, 7 ... positioning system, 9 ... computer, 100 ... GPS module, 200 ... IMU, 202 ... acceleration sensor, 204 ... gyro sensor, 400 ... arithmetic processing unit, 500 ... Processing unit, 502 ... Action type determination unit, 504 ... Real-time measurement processing unit, 506 ... Correction processing unit, 508 ... Positioning control unit, 510 ... Speed estimation type correction unit, 600 ... Storage unit, 602 ... Position information measurement program, 604 ... Speed estimation formula information, 606 ... INS calculation formula information, 608 ... IMU log data, 610 ... GPS log data, 612 ... INS log data

Claims (16)

It is a position measurement method in which the arithmetic processing unit measures the position information using the measurement signal of the inertial measurement unit.
The inertial measurement unit is attached to a predetermined part of the user who moves periodically with the movement or movement of the user, and measures at each measurement time at a given measurement time interval.
The user is equipped with a satellite positioning device that performs positioning at each positioning time at a given positioning time interval longer than the measurement time interval at the predetermined portion or another portion.
The arithmetic processing unit is
Real-time measurement processing to measure the location information and
A correction process for correcting the measurement result of the real-time measurement process using reference navigation information based on the positioning information of the satellite positioning device, and a correction process.
And run
The real-time measurement process
To estimate the speed of the user based on the signal characteristics of the measurement signal that periodically appears due to the movement or movement.
To calculate the yaw angle based on the measurement signal,
Measuring the position information using the speed and the yaw angle,
Including
The reference navigation information is
Including the reference yaw angle
The correction process is
Performing yaw angle correction that corrects the yaw angle included in the measurement result based on the reference yaw angle,
Correcting the position information included in the measurement result based on the corrected yaw angle of the yaw angle correction, and
Including
The yaw angle correction is
Of the yaw angles of each measurement time included in the measurement result, the difference between the yaw angle corresponding to the positioning time and the reference yaw angle of the positioning time is subtracted or added by 360 degrees to align the codes. Even if the absolute value of the difference exceeds 360 degrees, it is rolled out so that it gradually increases with the passage of time of the positioning time .
To calculate the correction formula based on the change of the difference with respect to the passage of time of the positioning time ,
To make a correction that applies the correction formula to the yaw angle at each measurement time ,
including,
Position measurement method. The yaw angle correction is
Of the yaw angles of each measurement time included in a part of the period related to the measurement result, the difference between the yaw angle corresponding to the positioning time and the reference yaw angle of the positioning time is code-normalized. It is calculated by performing processing and rolling out, calculating a correction formula based on the change in the difference with respect to the passage of time of the positioning time, and applying the correction formula to the yaw angle for all the periods related to the measurement result. Applying and doing the first amendment,
Of the first corrected yaw angles, the difference between the yaw angle corresponding to the positioning time and the reference yaw angle of the positioning time is calculated by performing the code normalization process and rolling out. A second correction for calculating a correction formula based on a change in the difference with respect to the passage of time of the positioning time, and applying the correction formula to each of the first corrected yaw angles. ,
including,
The position measuring method according to claim 1. The yaw angle correction is
Of the second corrected yaw angles, the yaw angle corresponding to the positioning time is corrected by calculating a correction value for making the reference yaw angle of the positioning time, and the yaw angle not corresponding to the positioning time is corrected. The third correction, which corrects each of the yaw angles after the second correction, by correcting using the complement value based on the correction value.
including,
The position measuring method according to claim 2. The real-time measurement process
The acceleration of the measured acceleration signal included in the measured signal is obtained, and the period of the measured acceleration signal is determined based on the change in the acceleration.
To calculate the amplitude of the measured acceleration signal based on the period,
Including
The estimation includes estimating the speed based on the amplitude.
The position measuring method according to any one of claims 1 to 3. The arithmetic processing unit is
Based on the measurement signal, the action type of the user including at least whether the user is performing the locomotion or stopped is determined, and when it is determined that the user is performing the locomotion, the real-time measurement is performed. Execute the process,
The position measuring method according to any one of claims 1 to 4. The real-time measurement process
Calculating the distance traveled and
To measure the elapsed time of the locomotion and
To calculate the time required to move a predetermined unit distance based on the movement distance and the elapsed time, and
including,
The position measuring method according to any one of claims 1 to 5. The arithmetic processing unit is
Based on the user's predetermined end operation or the measurement signal, it is determined that the user has completed the locomotion, and when the end is determined, the correction process is executed.
The position measuring method according to any one of claims 1 to 6. The arithmetic processing unit is
Based on the measurement signal, it is determined that the user has stopped, and when the determination is made to stop, the correction process is executed.
The position measuring method according to any one of claims 1 to 6. The arithmetic processing unit is
The correction process is executed based on the recorded data amount or the number of recordings of the measurement result and the reference navigation information.
The position measuring method according to any one of claims 1 to 6. The arithmetic processing unit is
Controlling the positioning time interval of the satellite positioning device,
To execute,
The position measuring method according to any one of claims 1 to 9. Controlling the positioning time interval includes lengthening the positioning time interval when the elapsed time from the start of positioning satisfies a predetermined condition.
The position measuring method according to claim 10. Controlling the positioning time interval includes shortening the positioning time interval when the satellite positioning device cannot determine the positioning position or when it takes a predetermined time or more to determine the positioning position.
The position measuring method according to claim 10 or 11. Controlling the positioning time interval includes shortening the positioning time interval when the yaw angle changes by a predetermined angle or more.
The position measuring method according to any one of claims 10 to 12. The reference navigation information includes reference position information.
The correction process is
Correcting the position information so that the locus connecting the position information passes through the reference position information.
The position measuring method according to any one of claims 1 to 13. It is an electronic device equipped with an arithmetic processing unit, an inertial measurement unit, and a satellite positioning unit.
The electronic device is attached to a predetermined part of the user who moves periodically with the movement or movement of the user.
The inertial measurement unit makes measurements at each measurement time at a given measurement time interval.
The satellite positioning device performs positioning at each positioning time at a given positioning time interval longer than the measurement time interval.
The arithmetic processing unit is
Real-time measurement processing that measures position information using the measurement signal of the inertial measurement unit, and
A correction process for correcting the measurement result of the real-time measurement process using reference navigation information based on the positioning information of the satellite positioning device, and a correction process.
And run
The real-time measurement process
To estimate the speed of the user based on the signal characteristics of the measurement signal that periodically appears due to the movement or movement.
To calculate the yaw angle based on the measurement signal,
Measuring the position information using the speed and the yaw angle,
Including
The reference navigation information is
Including the reference yaw angle
The correction process is
Performing yaw angle correction that corrects the yaw angle included in the measurement result based on the reference yaw angle,
Correcting the position information included in the measurement result based on the corrected yaw angle of the yaw angle correction, and
Including
The yaw angle correction is
Of the yaw angles of each measurement time included in the measurement result, the difference between the yaw angle corresponding to the positioning time and the reference yaw angle of the positioning time is subtracted or added by 360 degrees to align the codes. It is calculated by rolling out so that the absolute value of the difference exceeds 360 degrees and gradually increases with the passage of time of the positioning time .
To calculate the correction formula based on the change of the difference with respect to the passage of time of the positioning time ,
To make a correction that applies the correction formula to the yaw angle at each measurement time ,
including,
Electronics. It is a positioning system configured by communication connection between an electronic device equipped with an arithmetic processing unit, an inertial measurement unit, and a satellite positioning device, and a computer.
The electronic device is attached to a predetermined part of the user who moves periodically with the movement or movement of the user.
The inertial measurement unit makes measurements at each measurement time at a given measurement time interval.
The satellite positioning device performs positioning at each positioning time at a given positioning time interval longer than the measurement time interval.
The arithmetic processing unit is
Real-time measurement processing that measures position information using the measurement signal of the inertial measurement unit,
And run
The real-time measurement process
To estimate the speed of the user based on the signal characteristics of the measurement signal that periodically appears due to the movement or movement.
To calculate the yaw angle based on the measurement signal,
Measuring the position information using the speed and the yaw angle,
Including
The computer is
Correction processing that corrects the measurement result of the real-time measurement processing using reference navigation information based on the positioning information of the satellite positioning device.
And run
The reference navigation information is
Including the reference yaw angle
The correction process is
Performing yaw angle correction that corrects the yaw angle included in the measurement result based on the reference yaw angle,
Correcting the position information included in the measurement result based on the corrected yaw angle of the yaw angle correction, and
Including
The yaw angle correction is
Of the yaw angles of each measurement time included in the measurement result, the difference between the yaw angle corresponding to the positioning time and the reference yaw angle of the positioning time is subtracted or added by 360 degrees to align the codes. It is calculated by performing processing and rolling out so that the absolute value of the difference gradually increases with the passage of time even when the absolute value of the difference exceeds 360 degrees .
To calculate the correction formula based on the change of the difference with respect to the passage of time of the positioning time ,
To make a correction that applies the correction formula to the yaw angle at each measurement time ,
including,
Positioning system.

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