Electronic device, pressure acquisition method, and program

Abstract

To reduce power consumption while ensuring the accuracy of the pressure value detected by a pressure sensor.SOLUTION: An electronic device 100 comprises a body movement detection unit 160 that detects the body movement of the user, a pressure detection unit 150 that detects pressure, and a control unit 110 that acquires body movement data indicating the magnitude of the body movement from the body movement detection unit 160 and acquires pressure data indicating the pressure value from the pressure detection unit 150 at a timing based on a period determined from changes over time in the acquired body movement data.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an electronic device, a pressure acquisition method, and a program. [Background technology]

[0002] In recent years, electronic devices that are worn on the wrist and measure and display the user's number of steps, amount of activity, etc., such as wearable devices such as smart watches and activity meters, have been developed. As a technology used in such electronic devices, for example, Patent Document 1 discloses a technology for acquiring altitude using a barometric pressure sensor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-8806 A Summary of the Invention [Problem to be solved by the invention]

[0004] The technology disclosed in Patent Document 1 acquires altitude based on the detection result of the air pressure sensor. At that time, the period in which the air pressure sensor detects the air pressure is changed based on the type of the determined moving state. Specifically, the period in which the air pressure is detected is made shorter when it is determined that the user is running than when it is determined that the user is walking, and the period in which the air pressure is detected is made even shorter when it is determined that the user is riding a bicycle than when it is determined that the user is running. Increasing the frequency with which the air pressure sensor detects the air pressure also increases power consumption, but by controlling the period in which the air pressure is detected in this way, the detection period becomes longer when the moving speed is slow, and power consumption by the air pressure sensor can be reduced. However, if there is body movement, the air pressure value detected by the air pressure sensor becomes unstable due to the influence of vibrations, wind pressure, etc. For example, in a waterproof air pressure sensor, the element that detects pressure is covered with gel for waterproofing, and when this gel is influenced by acceleration, it presses or pulls the element that detects the pressure, causing the detected air pressure value to be larger or smaller than the original air pressure. For this reason, if the period is simply changed based on the type of moving state, the error contained in the air pressure value detected by the air pressure sensor becomes large.

[0005] The present invention has been made in consideration of the above-mentioned situation, and aims to provide an electronic device, a pressure acquisition method, and a program that make it possible to reduce power consumption while ensuring the accuracy of the pressure value detected by the pressure sensor. [Means for solving the problem]

[0006] In order to achieve the above object, one aspect of the electronic device according to the present invention is to A body movement detection unit that detects a body movement of a user; A pressure detection unit that detects pressure; acquiring body movement data indicating a magnitude of the body movement from the body movement detection unit; acquiring pressure data indicating a value of the pressure from the pressure detection unit at a timing based on a period determined from a change over time in the acquired body movement data; A control unit; Equipped with. Effect of the Invention

[0007] According to the present invention, it is possible to reduce power consumption while ensuring the accuracy of the pressure value detected by the pressure sensor. [Brief description of the drawings]

[0008] [Figure 1] 1 is a block diagram showing an example of a functional configuration of the electronic device according to a first embodiment. [Diagram 2] FIG. 2 is a diagram showing a state in which the electronic device according to the first embodiment is worn on the left wrist of a user. [Diagram 3] 5 is a diagram showing an example of acceleration detected by the electronic device according to the first embodiment. FIG. [Figure 4] 4 is a diagram illustrating an example of air pressure values ​​detected by the electronic device of the first embodiment and altitude values ​​calculated in comparison on the same time axis. FIG. [Diagram 5] 4 is an example of a flowchart of a main process according to the first embodiment. [Figure 6] 4 is an example of a flowchart of an air pressure measurement process according to the first embodiment. [Figure 7] 13 is a flowchart illustrating an example of a main process according to the second embodiment. [Figure 8] 13 is an example of a flowchart of a step counting process according to the second embodiment. [Figure 9] 11 is a diagram showing an example of acceleration and air pressure values ​​detected by the electronic device according to the second embodiment and calculated altitude values ​​compared on the same time axis. FIG. [Figure 10] 13 is an example of a flowchart of an air pressure measurement process according to the second embodiment. [Figure 11] FIG. 11 is a block diagram showing an example of a functional configuration of an electronic device according to a third embodiment. [Figure 12] 13 is a first portion of an example of a flowchart of an air pressure measurement process according to a third embodiment. [Figure 13] 13 is a second part of an example of a flowchart of an air pressure measurement process according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Electronic devices and the like according to embodiments will be described with reference to the drawings. Note that the same or corresponding parts in the drawings are given the same reference numerals.

[0010] (Embodiment 1) The electronic device of embodiment 1 is an information processing device that is worn on the user's wrist and can measure the current altitude (elevation) using a barometric pressure sensor and the user's activity level using a motion sensor, such as a smart watch or an electronic watch.

[0011] As shown in FIG. 1, the electronic device 100 includes a control unit 110, a storage unit 120, an input unit 130, an output unit 140, a pressure detection unit 150, a body movement detection unit 160, and a communication unit 170.

[0012] The control unit 110 is composed of a processor such as a CPU (Central Processing Unit). The control unit 110 executes processes for implementing various functions of the electronic device 100 and main processing (described later) by using programs stored in the storage unit 120. The control unit 110 also has a timer function and can measure time and clock the clock. The control unit 110 also supports multi-threading and can execute multiple processes in parallel.

[0013] The storage unit 120 stores programs executed by the control unit 110 and necessary data. The storage unit 120 may include, but is not limited to, a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, etc. Note that the storage unit 120 may be provided inside the control unit 110.

[0014] The input unit 130 is a user interface such as a push button switch, a touch panel, etc., and receives operational input from a user. When the input unit 130 includes a touch panel, the touch panel may be integrated with the display of the output unit 140.

[0015] The output unit 140 includes a display such as a liquid crystal display or an organic EL (Electro-Luminescence) display, and displays a display screen that provides the functions of the electronic device 100, an operation screen, and the like.

[0016] The pressure detection unit 150 is a pressure sensor that detects pressure, and outputs the pressure value detected by the pressure sensor to the control unit 110 as pressure data. In this embodiment, the pressure detection unit 150 is an air pressure sensor that detects the pressure of the surrounding atmosphere. In this embodiment, the pressure detection unit 150 includes a pressure receiving element whose resistance value changes when pressure is applied, and calculates air pressure based on the change in resistance value detected by the pressure receiving element. The control unit 110 can acquire the air pressure value detected by the air pressure sensor included in the pressure detection unit 150 as air pressure data at any timing. In this embodiment, the timing at which the control unit 110 acquires air pressure data changes depending on the user's body movement detected by the body movement detection unit 160, and acquires the air pressure value at every air pressure sampling period of 1 / 25 seconds (0.04 seconds) (i.e., at an air pressure sampling frequency of 25 Hz), for example.

[0017] If electronic device 100 is likened to a wristwatch, the air pressure sensor is often located on the 3 o'clock or 9 o'clock side of the watch, but the following explanation assumes that the air pressure sensor is located on the 9 o'clock side.

[0018] The body movement detection unit 160 is a motion sensor that detects the body movement of the user. In this embodiment, the body movement detection unit 160 includes an acceleration sensor that detects acceleration in each of three mutually orthogonal axes (x-axis, y-axis, and z-axis). The control unit 110 can acquire the acceleration value detected by the acceleration sensor included in the body movement detection unit 160 at any timing. In this embodiment, the control unit 110 acquires the acceleration at every acceleration sampling period of 0.01 seconds (i.e., at an acceleration sampling frequency of 100 Hz).

[0019] The communication unit 170 is a network interface compatible with, for example, a wireless LAN (Local Area Network), LTE (Long Term Evolution), etc. The electronic device 100 can communicate with the Internet and other devices via the communication unit 170.

[0020] The electronic device 100 is worn on the user's wrist with a band 190 as shown in Fig. 2. The arm on which the electronic device 100 is worn may be either the right arm or the left arm, but Fig. 2 shows the case where the electronic device is worn on the back of the left hand.

[0021] 2, the direction from the hand to the elbow is the x-axis, the direction from the thumb to the little finger is the y-axis, and the direction from the side of the wrist where the palmaris longus muscle is located (palm side) to the back side (back of the hand) is the z-axis. However, in this embodiment, the individual values ​​of the acceleration axes are not important, and the overall acceleration value is important, so the absolute value obtained by combining the values ​​of the three axes using the L2 norm is used as the acceleration value.

[0022] When a user wears electronic device 100 and walks as shown in FIG. 2, control unit 110 acquires acceleration from body movement detection unit 160 as a discrete signal sampled at an acceleration sampling frequency, and acquires air pressure values ​​from pressure detection unit 150 as a discrete signal sampled at an air pressure sampling frequency.

[0023] For example, Fig. 3 shows an example of a graph of acceleration values ​​when a user wears electronic device 100 and walks on flat ground, and Fig. 4 shows an example of graphs of atmospheric pressure values ​​and altitude values. Fig. 3 is a graph plotting the change over time of the L2 norm value of acceleration acquired by body movement detection unit 160 at a sampling frequency of 100 Hz. Fig. 4 is a graph of atmospheric pressure values ​​plotting the change over time of atmospheric pressure values ​​acquired by pressure detection unit 150 at a sampling frequency of 25 Hz, and a graph of altitude values ​​plotting the change over time of altitude values ​​calculated from the atmospheric pressure values.

[0024] From FIG. 3, it can be seen that the acceleration value reaches a peak (maximum value) approximately every 0.5 seconds. In other words, it takes a periodic value with a cycle of approximately 0.5 seconds (a frequency of approximately 2 Hz). This is synchronized with the cycle of the user's body movement (specifically, hand waving). Also, in this example, since the user is wearing electronic device 100 on his left arm, a greater impact of landing (= greater acceleration) is detected when the left foot lands on the ground than when the right foot lands on the ground. Therefore, as shown in FIG. 3, a large maximum value of acceleration is detected when the left foot lands on the ground.

[0025] Also, since the user is walking on flat ground, there is no change in the actual air pressure value. However, referring to the air pressure value graph in Figure 4, it can be seen that the acquired air pressure value changes in a range of about 0.4 hPa. This is because the pressure receiving element of the air pressure sensor is subjected to wind pressure and acceleration due to the user's body movements, which changes the resistance value of the pressure receiving element, causing the detected air pressure value to change.

[0026] For example, when the left foot lands (the timing when acceleration reaches a large maximum value in Figure 3), this corresponds to when the left arm is extended forward in the air pressure graph in Figure 4. When switching from landing on the left foot to landing on the right foot, the left arm is gradually pulled back, and the detected air pressure value gradually increases due to the influence of wind pressure and the pressure from the gel covering the pressure receiving element, and the maximum value is detected when the left arm is pulled all the way back. After that, as the left arm is extended forward, the detected air pressure value gradually decreases, and the minimum value is detected when the left arm is extended all the way forward. Comparing the acceleration graph in Figure 3 with the air pressure graph in the upper part of Figure 4, it can be seen that the air pressure value reaches a minimum value at the timing when acceleration reaches a large maximum value, and that the period of change in body movement and the period of change in air pressure value are almost synchronized (both are about 0.5 seconds).

[0027] It is also well known that the air pressure decreases as the altitude increases, but more precisely, the relationship between air pressure P and altitude h can be expressed by the following formula (1), where P0 is the sea level air pressure and T is the temperature. h=((P0 / P) 1 / 5.257 -1) × (T + 273.15) / 0.0065 … (1)

[0028] From formula (1), it can be seen that even if P0 or T changes slightly, it does not affect the value of h very much. Therefore, for example, if P0 is set to 1013.25 hPa and T is set to 20 degrees Celsius, the control unit 110 can calculate an approximate numerical value of the altitude value from the value of the atmospheric pressure obtained from the pressure detection unit 150 using formula (1). Note that, for T, if the electronic device 100 is equipped with a temperature sensor, the air temperature obtained from the temperature sensor may be used. Also, if the electronic device 100 can obtain the current sea level pressure from the Internet or the like, the obtained sea level pressure may be used as P0. Also, the user may be able to input the values ​​of T and P0.

[0029] For example, when altitude values ​​are calculated from the respective atmospheric pressure values ​​in the atmospheric pressure graph shown by solid line 203 in the upper part of Fig. 4, an altitude graph as shown by solid line 200 in the lower part of Fig. 4 is obtained. In this example, since the user is walking on flat ground, the actual altitude value does not change, but the atmospheric pressure value obtained from pressure detection unit 150 changes by a width of about 0.4 hPa in response to body movement as shown in the upper part of Fig. 4 (graph of atmospheric pressure values), and as a result, the calculated altitude value also changes by a width equivalent to about 4 m as shown in the lower part of Fig. 4 (graph of altitude values).

[0030] However, if the timing of acquiring the atmospheric pressure value used in calculating the altitude value is synchronized with the period of body movement, the range of change in the calculated altitude value can be significantly reduced. If the altitude value is calculated using the atmospheric pressure value (values ​​shown by circles or squares in the graph in the upper part of FIG. 4) acquired at a sampling period of about 0.5 seconds (i.e., a sampling frequency of about 2 Hz), a graph such as that shown by the dashed line 201 or dotted line 202 in the lower part of FIG. 4 is obtained, and it can be seen that the range of change in the altitude value is suppressed to less than 1 m in both cases. In FIG. 4, the circles which are the sampling points (points where the atmospheric pressure value was acquired) in the graph in the upper part of FIG. 4 and the altitude values ​​corresponding to each of these sampling points (values ​​shown by circles in the lower part of FIG. 4) are connected by dashed lines. Since the sampling period in FIG. 4 is about 0.5 seconds, the dashed lines are also drawn every about 0.5 seconds, and it can be seen that the atmospheric pressure value is acquired and the corresponding altitude value is calculated every about 0.5 seconds.

[0031] In many cases, a user would normally like to know how much the altitude value has changed, rather than the altitude value itself. In that case, if an altitude value such as that shown by the solid line 200 in the lower part of Fig. 4 is acquired, there is a problem that the altitude value appears to have changed even though it has not actually changed. In contrast, if the altitude value is such as that shown by the dashed line 201 or dotted line 202, the altitude value does not appear to have changed that much, so it can be said that the user can easily grasp the change in the actual altitude value.

[0032] Thus, even when the air pressure value detected by the air pressure sensor fluctuates due to body movement or the like, the air pressure measurement process that allows the control unit 110 to obtain a stable air pressure value will be described with reference to the drawings. The air pressure measurement process is periodically called and executed from the main process of the electronic device 100, so the main process will first be described with reference to Fig. 5. The main process is executed when the power of the electronic device 100 is turned on.

[0033] First, the control unit 110 performs an initial setting process for the electronic device 100 (step S101). In the initial setting process, the timer is initialized (cancelled), interrupt settings (setting of timing interrupt, input interrupt, etc.) are performed, etc. A timing interrupt is an interrupt that occurs to advance the clock, and occurs, for example, every time one second elapses. An input interrupt is generated when the input unit 130 receives some kind of operational input, such as a key input.

[0034] In step S101, processing for detecting periodic movements of the user (periodic movement detection processing) is also started in a thread separate from the main processing. The periodic movement detection processing can be realized in any way. For example, as shown in Fig. 3, the acquired acceleration time series data is Fourier transformed to acquire a graph of frequency components, and if a clear peak is present in the graph, the reciprocal of the frequency corresponding to the part corresponding to the peak (the part where the frequency component is maximum) is taken as the period of the body movement to detect periodic movements.

[0035] The method of detecting the periodic motion of the user is not limited to the method using the Fourier transform, and may be, for example, a period of the body motion obtained by finding the interval of the timing at which the acceleration reaches a maximum value. Specifically, the control unit 110 first counts the number of maximum values ​​equal to or greater than a predetermined threshold value per unit time (e.g., 1 second) from the acceleration data within a past predetermined time (e.g., 10 seconds) (in the example shown in FIG. 3, there are four maximum values ​​(two right foot landings and two left foot landings) between 0.5 seconds and 1.5 seconds). Then, if the variance of the number of maximum values ​​per unit time within the past predetermined time is equal to or less than a predetermined threshold value, it is determined that the acceleration is changing periodically. Note that, although the variance is used here as an index showing the variation in the number of maximum values, a standard deviation or the like may be used instead of the variance.

[0036] The sampling period is calculated by dividing the number of seconds in a given time in the past (e.g., 10 seconds) by the total number of maximum values ​​within that time, and then multiplying the result by 2. For example, if there were 40 maximum values ​​in the past 10 seconds, then 10 seconds ÷ 40 × 2 = 0.5 seconds, so the sampling period is calculated to be 0.5 seconds. Note that the reason for multiplying by 2 at the end is that we want to define the period from when the left foot (right foot) lands until the next time the left foot (right foot) lands again (the period for two maximum values) as one period.

[0037] Also, if the electronic device 100 has a pedometer function (a pedometer that counts one step each time the right foot lands and the left foot lands), the number of steps (STEP steps) on both the left and right sides in a predetermined period (DT seconds) may be counted and the cycle calculated as DT / (STEP÷2). STEP is divided by 2 here because, for example, the time from when the right foot lands to when the right foot lands again (during which the left foot lands once) should be considered as one cycle.

[0038] 5, next, the control unit 110 waits until some interrupt occurs (step S102). When some interrupt occurs (time count interrupt, input interrupt, etc.), the process proceeds to step S103.

[0039] Then, the control unit 110 performs processing such as timing (step S103). This processing is processing performed in the first half of the main processing, such as processing for advancing the clock by one second when a timing interrupt occurs in step S102.

[0040] Next, the control unit 110 performs an air pressure measurement process (step S104). The air pressure measurement process will be described in detail later.

[0041] Then, the control unit 110 performs processing such as display (step S105). This processing is performed in the latter half of the main processing, such as, for example, calculating an altitude value from the atmospheric pressure value acquired in step S104 and displaying the altitude value on the output unit 140, or displaying the current time on the output unit 140. Note that when the control unit 110 displays the altitude value on the output unit 140, it may display the current sampling period (or an index indicating a value equivalent to the sampling period, such as a sampling rate) together with the altitude value. By displaying the current sampling period together with the altitude value in this way, the user can determine whether the sampling period is the default sampling period or the sampling period adjusted to the user's body movement data.

[0042] Then, the control unit 110 determines whether or not to turn off the power (step S106). Specifically, it determines whether or not the user has issued an instruction to turn off the power of the electronic device 100 via the input unit 130 or the like.

[0043] If the power is not to be turned off (step S106; No), the process returns to step S102. If the power is to be turned off (step S106; Yes), the control unit 110 ends the main process.

[0044] This main process executes the air pressure measurement process every time an interrupt occurs. Next, this air pressure measurement process will be described with reference to Fig. 6. This air pressure measurement process is a process that sets a timer 1 with an appropriate period according to the body movement detected by the body movement detection unit 160, and acquires the air pressure value according to the period set in the timer 1 (for example, every period of "timer 1 period x N"). This allows the control unit 110 to acquire the air pressure value sampled at an air pressure sampling period appropriate for each occasion.

[0045] First, the control unit 110 determines whether or not there is a request for an air pressure value (step S121). For example, when a user is running, he or she may want to periodically check the altitude value, and the control unit 110 determines whether or not there is a request to obtain an air pressure value from a user operation, an altitude display application, or the like.

[0046] If there is no request for an atmospheric pressure value (step S121; No), the control unit 110 cancels (stops) the timer 1 (step S122) and ends the atmospheric pressure measurement process.

[0047] If there is a request for an air pressure value (step S121; Yes), the control unit 110 determines whether or not the timer 1 is operating (step S123).

[0048] If timer 1 is not running (step S123; No), control unit 110 determines whether or not body movement detection unit 160 has detected a periodic movement (step S130). For example, if body movement detection unit 160 detects a periodic change in acceleration as shown in Fig. 3, then body movement detection unit 160 has detected a periodic movement. Note that the process for determining whether or not there is a periodic change in the acceleration detected by body movement detection unit 160 (periodic movement detection process) is started in step S101 of the main process as described above, and is executed in parallel with other processes.

[0049] When body movement detection unit 160 detects periodic movement (step S130; Yes), control unit 110 sets timer 1 so that an interrupt occurs at the same cycle as the detected periodic movement (e.g., 0.5 seconds), starts timer 1 operation, and assigns 4 to variable N (step S131). Note that variable N is a variable that sets how many times the cycle of timer 1 (cycle of the detected periodic movement) the air pressure value is sampled at.

[0050] If 1 is assigned to N, the air pressure value will be sampled in sync with the cycle of Timer 1, so the accuracy of the acquired air pressure will be higher, but the more frequent sampling will result in higher power consumption. Here, 4 is assigned as the value of N that can maintain accuracy while suppressing power consumption. This means that the air pressure value will be sampled at a cycle four times the cycle of the detected cyclical movement. Note that the cycle represented by cycle x N set in Timer 1 here is the cycle at which the air pressure value is sampled when a cycle is detected from the user's body movement, and is also called the second sampling cycle.

[0051] Then, the control unit 110 assigns the value of the variable N to the variable CT (step S129), and ends the air pressure measurement process.

[0052] On the other hand, if it is not determined in step S130 that body movement detection unit 160 has detected periodic movement (step S130; No), control unit 110 sets timer 1 so that an interrupt occurs at a sufficiently short period (for example, 1 / 25 seconds), starts timer 1 operation, and assigns 1 to variable N (step S132). Then, control unit 110 assigns the value of variable N to variable CT (step S129), and ends the air pressure measurement process.

[0053] The sufficiently short period set in the timer 1 in step S132 is a period for sampling the air pressure value when the period cannot be detected from the user's body movement, and is also called the first sampling period. In this case, the user may be moving quite randomly or may be almost stationary. When the user is almost stationary, not only when the user is stationary on flat ground, but also when the user is riding on an elevator, escalator, vehicle, etc., in which case the altitude changes considerably in a short period of time. Therefore, the first sampling period must be at least shorter than the second sampling period, and it is desirable to set the sufficiently short period to, for example, 1 / 20 seconds or less. By setting the first sampling period to such a sufficiently short period, it is possible to follow altitude changes caused by elevators, etc.

[0054] On the other hand, if it is determined in step S123 that timer 1 is operating (step S123; Yes), the control unit 110 determines whether or not a timer 1 interrupt has occurred in the above-mentioned step S102 (step S124). If a timer 1 interrupt has not occurred (step S124; No), it is not time to obtain an atmospheric pressure value, so the control unit 110 ends the atmospheric pressure measurement process.

[0055] If a timer 1 interrupt has occurred (step S124; Yes), control unit 110 subtracts 1 from variable CT (step S125), and determines whether the value of variable CT is 0 (step S126).

[0056] If the value of the variable CT is not 0 (step S126; No), it is not yet time to obtain atmospheric pressure, and the control unit 110 ends the atmospheric pressure measurement process.

[0057] If the value of the variable CT is 0 (step S126; Yes), the control unit 110 drives the air pressure sensor of the pressure detection unit 150 to sample and acquire the air pressure value (step S127). Then, the control unit 110 stores the acquired air pressure value in the storage unit 120 (step S128).

[0058] However, in step S128, the process branches out into two options: either store the air pressure value acquired based on the period set in timer 1 as is, or store the average value of a predetermined number of air pressure values ​​accumulated as the air pressure value. For example, if the period set in timer 1 is shorter (e.g., 1 / 25 second) than a threshold value (e.g., 1 / 4 second), control unit 110 accumulates a predetermined number of air pressure values ​​acquired in step S127 (e.g., the reciprocal of the period set in timer 1 (e.g., 25)) and stores the average value of the accumulated air pressure values ​​as the air pressure value. If the period set in timer 1 is equal to or greater than a threshold value (e.g., 1 / 4 second) (e.g., 0.5 seconds), control unit 110 stores the air pressure value acquired in step S127 as is as the air pressure value.

[0059] Then, the control unit 110 assigns the value of the variable N to the variable CT (step S129), and ends the air pressure measurement process.

[0060] Through the above air pressure measurement process, when periodic body movement is detected, the control unit 110 acquires air pressure at a timing based on the period of the body movement (a period synchronized with the period of the body movement), and when no such body movement is detected, the control unit 110 acquires air pressure at a sufficiently short period. This allows the electronic device 100 to reduce power consumption while ensuring the accuracy of the air pressure value detected by the air pressure sensor. Note that when there is body movement, such as when the user is walking, the acquired air pressure value is affected by the body movement, making it difficult to acquire an accurate air pressure value (and altitude). However, even in such a case, by acquiring the air pressure value in accordance with the period of the body movement, fluctuations in the acquired air pressure value can be suppressed, so that the user's request to "know how much the altitude has changed" can be satisfied.

[0061] (Embodiment 2) Since the electronic device 100 according to the first embodiment needs to determine whether or not periodic body movements are detected by the body movement detection unit 160, it is necessary to execute a periodic movement detection process in parallel with other processes. However, if the electronic device has a pedometer function, a process for counting the number of steps can be used instead of the periodic movement detection process. Here, as the second embodiment, an electronic device 101 having a function for counting the number of steps will be described.

[0062] The functional configuration of the electronic device 101 according to the second embodiment is similar to that of the electronic device 100 according to the first embodiment, as shown in Fig. 1. Moreover, the way in which the electronic device 101 according to the second embodiment is worn by a user is similar to that of the electronic device 100 according to the first embodiment, as shown in Fig. 2.

[0063] The air pressure value measured by the electronic device 101 according to the second embodiment is also affected by the user's body movements, as is the electronic device 100 according to the first embodiment. However, since the electronic device 101 has a function of counting the number of steps, a step counting process is also called in the main process. Therefore, first, the main process according to the second embodiment will be described with reference to Fig. 7. This main process is executed when the electronic device 101 is powered on.

[0064] The process from step S201 to step S203 is similar to the process from step S101 to step S103 in the main process (FIG. 5) according to embodiment 1, and therefore the description will be omitted. However, in step S201, a process is also performed in which an initial value (e.g., 1) is substituted for a variable N used in a step counting algorithm described later, and the value of the variable N is substituted for a variable CT.

[0065] Then, the control unit 110 executes a step counting process in step S204. The step counting process will be described in detail later. The processes from step S205 to step S207 are similar to the processes from step S104 to step S106 in the main process (FIG. 5) according to the first embodiment, and therefore the description thereof will be omitted.

[0066] Next, the step counting process executed in step S204 of the above-mentioned main process (FIG. 7) will be described with reference to FIG.

[0067] First, the control unit 110 acquires acceleration using the acceleration sensor of the body movement detection unit 160 (step S221), and judges whether or not the user is walking (step S222). There is no limit to the method for judging whether or not the user is walking, but for example, if the acceleration periodically alternates between large maximum values ​​(maximum values ​​indicated by circles) and small maximum values ​​(maximum values ​​indicated by squares) as shown in the upper part of Fig. 9, the control unit 110 judges that the user is walking.

[0068] As described above, a greater impact (=greater acceleration) is detected when the user lands on the ground with his / her left foot than when the user lands on the ground with his / her right foot, so in the acceleration graph in the upper part of Fig. 9, the maximum values ​​indicated by circles are the acceleration when the left foot lands, and the maximum values ​​indicated by squares are the acceleration when the right foot lands. In other words, there are two types of maximum values: a maximum value (circle) when the user lands on the left foot, and a maximum value (square) when the user lands on the right foot.

[0069] As described above, when the left foot lands (the timing of the maximum value indicated by the circle) corresponds to when the left arm is extended forward in the graph of air pressure values ​​in the middle of Figure 9, and the air pressure value detected when switching from landing on the left foot to landing on the right foot gradually increases, and the maximum air pressure value is detected when the left arm is pulled all the way back. After that, as the left arm is extended forward, the air pressure value detected gradually decreases, and the minimum air pressure value is detected when the left arm is extended all the way forward.

[0070] As can be seen from the above formula (1), as the atmospheric pressure P increases, the altitude h decreases, and as the atmospheric pressure P decreases, the altitude h increases. Therefore, as shown in the graphs in the middle and bottom of Fig. 9, a minimum value of the atmospheric pressure value corresponds to a maximum value of the altitude value, and a maximum value of the atmospheric pressure value corresponds to a minimum value of the altitude value. Referring to the bottom of Fig. 9, the altitude value graph shown by the solid line 200 repeatedly moves up and down in a range of about 4 m in response to the user's body movement, but at the timing corresponding to the maximum value indicated by the circle in the acceleration, the altitude value also becomes close to the maximum value, and by connecting these values, a relatively stable altitude value is obtained, as shown by the dashed line 204.

[0071] Returning to FIG. 8, if the user is not walking (step S222; No), the control unit 110 sets the variable CT to 0 (step S223) and ends the step counting process.

[0072] On the other hand, if the user is walking (step S222; Yes), the control unit 110 judges whether or not the number of steps has been detected (step S224). There is no limit to the method for judging whether or not the number of steps has been detected, but for example, when it is confirmed that the acceleration has reached the maximum value (two types of maximum values ​​indicated by circles and squares) shown in the upper part of Fig. 9, the control unit 110 judges that the number of steps has been detected. In other words, the control unit 110 counts the number of steps at the timing when either of these two types of maximum values ​​is detected.

[0073] If the number of steps has not been detected (step S224; No), the control unit 110 ends the number of steps measurement process.

[0074] On the other hand, if the number of steps is detected (step S224; Yes), the control unit 110 counts the number of steps (step S225). Specifically, the control unit 110 adds 1 to the variable stored in the storage unit 120 as the current number of steps.

[0075] Then, the control unit 110 determines whether or not there is a request for an atmospheric pressure value (step S226). This determination is the same as the determination in step S121 of the atmospheric pressure measurement process (FIG. 6) according to embodiment 1. If there is no request for an atmospheric pressure value (step S226; No), the control unit 110 sets the variable CT to 0 (step S223) and ends the step count measurement process.

[0076] If there is a request for an air pressure value (step S226; Yes), the control unit 110 determines whether or not the value of the variable CT is 0 (step S227). If the value of the variable CT is not 0 (step S227; No), the control unit 110 subtracts 1 from the variable CT (step S228) and ends the step counting process.

[0077] If the variable CT is 0 (step S227; Yes), the control unit 110 turns on the air pressure measurement flag (step S229), assigns the value of the variable N to the variable CT (step S230), and ends the step count measurement process.

[0078] This step counting process not only counts the number of steps, but also turns on the air pressure measurement flag when a step is detected.

[0079] Next, the air pressure measurement process executed in step S205 of the above-mentioned main process (FIG. 7) will be described with reference to FIG.

[0080] First, the control unit 110 determines whether or not the atmospheric pressure measurement flag is ON (step S251). If the atmospheric pressure measurement flag is not ON (step S251; No), the control unit 110 ends the atmospheric pressure measurement process.

[0081] If the air pressure measurement flag is ON (step S251; Yes), the control unit 110 drives the air pressure sensor of the pressure detection unit 150 to sample and acquire the air pressure value (step S252). Then, the control unit 110 stores the acquired air pressure value as is in the storage unit 120 (step S253). Then, the control unit 110 turns the air pressure measurement flag OFF (step S254) and ends the air pressure measurement process.

[0082] Through the above-described atmospheric pressure measurement process, the control unit 110 acquires the atmospheric pressure at the timing when the number of steps is detected. This enables the electronic device 101 to reduce power consumption while ensuring the accuracy of the atmospheric pressure value detected by the atmospheric pressure sensor.

[0083] The variable N set in step S201 of the main process (Fig. 7) is a variable that sets how many steps to skip while walking to acquire air pressure, and if N=1, air pressure is acquired every other step, that is, every even number of steps. As can be seen by referring to the acceleration graph shown in the upper part of Fig. 9, the timing of maximum acceleration values ​​(timings at which the number of steps is counted) alternate between large maximum values ​​(circles) and small maximum values ​​(squares).

[0084] As can be seen by comparing the acceleration graph shown in the top row of FIG. 9 with the atmospheric pressure graph shown in the middle row, the atmospheric pressure value detected by the atmospheric pressure sensor when the acceleration reaches a large maximum value (circle) is significantly different from the atmospheric pressure value detected by the atmospheric pressure sensor when the acceleration reaches a small maximum value (square). Therefore, in order to obtain a stable atmospheric pressure value (i.e., to calculate a stable altitude value), it is necessary to determine at which maximum value the atmospheric pressure value will be obtained. To do this, the value of the variable N is set to an odd number. For example, if N is set to 3, the atmospheric pressure can be obtained every multiple of 4 steps (i.e., only the large maximum value or only the small maximum value).

[0085] By acquiring the air pressure in this manner, the control unit 110 can calculate a stable altitude. For example, referring to Fig. 9, by the control unit 110 acquiring the air pressure value at the timing when the acceleration reaches a large maximum value (circle), a relatively stable altitude value can be calculated as shown by the dashed line 204 in the altitude value graph at the bottom.

[0086] (Embodiment 3) In the above-described embodiments, electronic devices 100, 101 include body movement detection unit 160, which detects the period of body movement. However, if periodic body movement is present, the value detected by the air pressure sensor will also change periodically, so it is possible to detect the period of body movement using pressure detection unit 150 even if body movement detection unit 160 is not included. Here, as a third embodiment, an electronic device 102 that detects the period of body movement using pressure detection unit 150 will be described.

[0087] The functional configuration of the electronic device 102 according to the third embodiment is a configuration in which the body movement detection unit 160 is removed from the electronic device 100 according to the first embodiment, as shown in Fig. 11. The electronic device 102 according to the third embodiment is worn by a user in the same manner as the electronic device 100 according to the first embodiment, as shown in Fig. 2.

[0088] The air pressure value measured by the electronic device 102 of embodiment 3 is also affected by the user's body movements, as is the case with the electronic device 100 of embodiment 1. However, since the electronic device 102 does not have a body movement detection unit 160, it is necessary to detect the period of body movements using the pressure detection unit 150.

[0089] The main processing according to the third embodiment is similar to the main processing according to the first embodiment (FIG. 5), and therefore a description thereof will be omitted. However, the periodic motion detection processing started in step S101 of the main processing detects the periodic motion of the user using the air pressure value obtained by the pressure detection unit 150, without using the body motion detection unit 160. That is, for example, as shown in FIG. 4, the time series data of the acquired air pressure value is Fourier transformed to obtain a graph of frequency components, and if a clear peak is present in the graph, the reciprocal of the frequency corresponding to the part corresponding to the peak (the part where the frequency component is maximum) is taken as the period of the body motion to detect the periodic motion. Also, for example, the interval between the timings at which the air pressure value takes a maximum value (or a minimum value) may be found and taken as the period of the body motion.

[0090] Next, an air pressure measurement process for detecting a body movement period and acquiring an air pressure value without the body movement detection unit 160 will be described with reference to Figures 12 and 13. This process is executed in step S104 of the main process (Figure 5).

[0091] In FIG. 12, the processes in step S321 and steps S323 to S329 are similar to the processes in step S121 and steps S123 to S129 in the air pressure measurement process (FIG. 6) according to the first embodiment, and therefore will not be described.

[0092] In the air pressure measurement process according to the third embodiment, not only timer 1 but also timers 2 and 3 are used as timers, so in step S322, the control unit 110 cancels (stops) timer 1, timer 2, and timer 3, and terminates the air pressure measurement process.

[0093] If the determination in step S324 is No, or if the determination in step S326 is No, the process proceeds from step S329 to step S330, where control unit 110 determines whether or not timer 3 is operating.

[0094] If timer 3 is running (step S330; Yes), the control unit 110 determines whether or not a timer 3 interrupt has occurred in the above-mentioned step S102 (step S331). If a timer 3 interrupt has not occurred (step S331; No), the control unit 110 ends the air pressure measurement process. If a timer 3 interrupt has occurred (step S331; Yes), the control unit 110 proceeds to step S351 shown in FIG. 13.

[0095] On the other hand, if timer 3 is not operating (step S330; No), the control unit 110 determines whether or not a timer 2 interrupt has occurred in the above-mentioned step S102 (step S332). If a timer 2 interrupt has not occurred (step S332; No), the control unit 110 ends the air pressure measurement process. If a timer 2 interrupt has occurred (step S332; Yes), the process proceeds to step S351 shown in FIG.

[0096] Also, if the determination in step S323 is No, the process proceeds to step S351 shown in FIG.

[0097] In step S351, the control unit 110 determines whether or not the atmospheric pressure sensor has detected a periodic operation. For example, if the atmospheric pressure sensor can detect a periodic change in the atmospheric pressure value as shown in Fig. 4, the atmospheric pressure sensor detects a periodic operation. Note that the process for determining whether or not there is a periodic change in the atmospheric pressure value detected by the atmospheric pressure sensor (periodic operation detection process) is started in step S101 of the main process as described above, and is executed in parallel with other processes.

[0098] When the atmospheric pressure sensor detects a periodic operation (step S351; Yes), the control unit 110 sets the timer 1 so that an interrupt occurs at the same period (e.g., 0.5 seconds) as the period of the detected periodic operation, starts the timer 1 operation, and assigns 4 to the variable N (step S352). The process of step S352 is the same as the process of step S131 of the atmospheric pressure measurement process (FIG. 6) of the first embodiment.

[0099] Next, control unit 110 assigns the value of variable N to variable CT (step S353). Then, control unit 110 sets timer 2 so that an interrupt occurs after a predetermined time (e.g., 30 seconds) has elapsed, and starts the operation of timer 2 (step S354). The predetermined time set in timer 2 in step S354 is the time for which the time currently set in timer 1 is maintained. As described above, when an interrupt occurs in timer 2, control unit 110 proceeds from step S332 to step S351, determines whether or not a periodic operation has been detected by the air pressure sensor, and resets timer 1.

[0100] Then, the control unit 110 cancels (stops) the timer 3 (step S355), and ends the air pressure measurement process.

[0101] On the other hand, if it is not determined in step S351 that the atmospheric pressure sensor has detected a periodic operation (step S351; No), the control unit 110 sets timer 1 so that an interrupt occurs at a sufficiently short period (for example, 1 / 25 seconds), starts the operation of timer 1, and assigns 1 to variable N (step S356). The process of step S356 is similar to the process of step S132 in the atmospheric pressure measurement process (FIG. 6) of the first embodiment.

[0102] Next, control unit 110 assigns the value of variable N to variable CT, and turns on the frequency fixation flag (step S357). Then, control unit 110 cancels (stops) timer 2 (step S358).

[0103] Then, control unit 110 sets timer 3 so that an interrupt occurs after a predetermined time (e.g., 10 seconds), starts operation of timer 3 (step S359), and ends the air pressure measurement process. The predetermined time set in timer 3 in step S359 is a time sufficient for detecting periodic operations in the periodic operation detection process. As described above, when an interrupt occurs in timer 3, control unit 110 proceeds from step S331 to step S351, determines whether or not a periodic operation has been detected by the air pressure sensor, and resets timer 1.

[0104] By the air pressure measurement process described above, the electronic device 102 can acquire air pressure in synchronization with the periodic movements of the user, even without the body movement detection unit 160. This allows the electronic device 102 to reduce power consumption while ensuring the accuracy of the air pressure value detected by the air pressure sensor.

[0105] (Modification) In the above-described first and second embodiments, acceleration is used as body movement data indicating the magnitude of the user's body movement, but the body movement data is not limited to acceleration, and for example, angular velocity may be used. When angular velocity is used as the body movement data, the body movement detection unit 160 is provided with a gyro sensor. Then, the control unit 110 detects the periodic movement of the user based on, for example, the angular velocity of the arm detected by the gyro sensor.

[0106] Moreover, the body movement detection unit 160 may include a geomagnetic sensor that detects geomagnetism, and the geomagnetic value may be used as the body movement data. Moreover, the body movement detection unit 160 may include at least one sensor that detects body movement, such as an acceleration sensor, a gyro sensor, a geomagnetic sensor, etc., as a body movement sensor (motion sensor), and data obtained by combining values ​​acquired from these sensors may be used as the body movement data. Then, the control unit 110 may detect the periodic movement of the user based on the body movement data acquired from the body movement sensor.

[0107] In the above embodiment, the pressure detection unit 150 is an air pressure sensor that detects the pressure of the surrounding atmosphere. However, the pressure detection unit 150 is not limited to an air pressure sensor. For example, the pressure detection unit 150 may be a water pressure sensor that detects water pressure underwater. When the user moves his / her body underwater, the water pressure sensor receives resistance from the surrounding water, and the detected water pressure fluctuates. However, if the user's body movement shows periodicity, the control unit 110 can obtain the water pressure value detected by the water pressure sensor as water pressure data at a timing based on the period, thereby obtaining a stable water pressure value, as in the case of an air pressure sensor.

[0108] Furthermore, the electronic devices 100, 101, 102 are not limited to smart watches or electronic watches, but may also be realized by computers such as smartphones equipped with the pressure detection unit 150, portable tablets, and PCs (Personal Computers). Specifically, in the above embodiment, the program for the air pressure measurement process and the like executed by the control unit 110 has been described as being stored in advance in the storage unit 120. However, the program may be stored in a non-transitory computer-readable recording medium such as a flexible disk, a CD-ROM (Compact Disc Read Only Memory), a DVD (Digital Versatile Disc), an MO (Magneto-Optical disc), a memory card, a USB memory, or the like, and distributed, and the program may be read and installed in a computer to configure a computer capable of executing each of the above-mentioned processes.

[0109] Furthermore, the program may be superimposed on a carrier wave and applied via a communication medium such as the Internet. For example, the program may be distributed by posting it on a bulletin board system (BBS) on a communication network. The program may then be started and executed under the control of an OS (Operating System) in the same manner as other application programs, thereby enabling the above-mentioned processes to be performed.

[0110] In addition, the control unit 110 may be configured by any processor alone, such as a single processor, a multiprocessor, or a multi-core processor, or may be configured by combining any of these processors with a processing circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array).

[0111] Although the above describes a preferred embodiment of the present invention, the present invention is not limited to the specific embodiment, and the present invention includes the invention described in the claims and its equivalents. [Explanation of symbols]

[0112] 100, 101, 102...electronic device, 110...control section, 120...storage section, 130...input section, 140...output section, 150...pressure detection section, 160...body movement detection section, 170...communication section, 190...band, 200, 203...solid lines, 201, 204...dashed lines, 202...dotted line

Claims

1. A body movement detection unit that detects a body movement of a user; A pressure detection unit that detects pressure; acquiring body movement data indicating a magnitude of the body movement from the body movement detection unit; acquiring pressure data indicating a value of the pressure from the pressure detection unit at a timing based on a period determined from a change over time in the acquired body movement data; A control unit; An electronic device comprising:

2. The control unit is Counting the number of steps based on the change over time in the acquired body movement data; the pressure data is acquired from the pressure detection unit at a timing for each predetermined number of steps in the counted number of steps, as the timing based on the cycle; 2. The electronic device according to claim 1.

3. The control unit is counting the number of steps at a timing when a maximum value in the change over time of the body movement data is detected; 3. The electronic device according to claim 2.

4. There are two types of maximum values, a maximum value when the user lands on the ground with his / her left foot and a maximum value when the user lands on the ground with his / her right foot, The control unit is The number of steps is counted at the timing when either of the two types of maximum values ​​is detected.

4. The electronic device according to claim 3.

5. The control unit is acquiring pressure data from the pressure detection unit at a timing corresponding to every even number of steps; 3. The electronic device according to claim 2.

6. The control unit is determining whether a period is detected in the change over time of the acquired body movement data; If the period is not detected, pressure data is acquired from the pressure detection unit in a first sampling period; When the period is detected, pressure data is acquired from the pressure detection unit at a second sampling period based on the period.

2. The electronic device according to claim 1.

7. The control unit is if the variance of the number of maximum values ​​per unit time within a predetermined time period of the acquired body movement data is equal to or less than a predetermined threshold, it is determined that the change is periodic, and pressure data is acquired from the pressure detection unit at a timing based on the period.

2. The electronic device according to claim 1.

8. The control unit is determining the period based on a value obtained by dividing the number of seconds of the predetermined time by the total number of the maximum values ​​within the predetermined time; 8. The electronic device according to claim 7.

9. A pressure detection unit that detects pressure; A control unit, The control unit is determining whether a period is detected in a time-dependent change in the air pressure data acquired from the pressure detection unit during a first sampling period; If the period is not detected, pressure data is acquired from the pressure detection unit at the first sampling period for a predetermined time. When the period is detected, pressure data is acquired from the pressure detection unit at a second sampling period based on the period for a predetermined time. After the predetermined time has elapsed, it is determined again whether or not a period is detected in the change over time of the pressure data acquired from the pressure detection unit in the first sampling period, and the acquisition of the pressure data from the pressure detection unit is repeated for the predetermined time in a period based on a result of the determination. electronic equipment.

10. The first sampling period is a sampling period that is shorter than the second sampling period.

10. The electronic device according to claim 9.

11. The second sampling period is an integer multiple of the detected period. The electronic device according to claim 10.

12. The second sampling period is four times the detected period. The electronic device according to claim 11.

13. The pressure detection unit detects atmospheric pressure, The control unit is obtaining air pressure data indicating the value of the air pressure from the pressure detection unit; The electronic device according to claim 1 .

14. The control unit is Calculating altitude based on the acquired air pressure data; 14. The electronic device according to claim 13.

15. The control unit: acquiring body movement data indicating a magnitude of the user's body movement from a body movement detection unit; acquiring pressure data indicating a pressure value from a pressure detection unit at a timing based on a period determined from a change over time in the acquired body movement data; Pressure acquisition method.

16. In the control section, acquiring body movement data indicating a magnitude of the user's body movement from the body movement detection unit; acquiring pressure data indicating a pressure value from a pressure detection unit at a timing based on a period determined from a change over time in the acquired body movement data; A program that executes a process.

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