Velocity calculation device, velocity calculation method, and velocity calculation program

Abstract

To provide a speed calculation device that can accurately calculate speed corresponding to the movement of an electronic device.SOLUTION: A speed calculation device 100 according to the present disclosure comprises a sensor information acquisition unit 111, a speed estimation unit 112, an average speed calculation unit 113, a relationship information calculation unit 114, and a speed-determining unit 115. The sensor information acquisition unit 111 acquires, from an acceleration sensor, sensor information relating to acceleration regarding an electronic device. The speed estimation unit 112 calculates, on the basis of the sensor information, an estimated speed estimated with respect to the movement of the electronic device. The average speed calculation unit 113 performs filtering and integration on the sensor information and calculates an average speed corresponding to the movement of the electronic device. The relationship information calculation unit 114 calculates relationship information indicating the correspondence relationship between the estimated speed and the average speed. The speed-determining unit 115 determines the speed corresponding to the current movement of the electronic device on the basis of the relationship information and the current estimated speed calculated by the speed estimation unit.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a velocity calculation device, a velocity calculation method, and a velocity calculation program. [Background technology]

[0002] A technology has been proposed that calculates values ​​such as acceleration related to the user's hand movements for an electronic device held and used by the user, determines whether the electronic device is being used appropriately based on the calculated results, and provides feedback to the user. Patent Document 1 discloses a toothbrush management and guidance system that provides guidance on tooth brushing activities when using an electric toothbrush. The management and guidance system disclosed in Patent Document 1 determines whether the user is brushing their teeth appropriately based on information obtained from an acceleration sensor attached to the toothbrush. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2020-534879 Summary of the Invention [Problem to be solved by the invention]

[0004] The management guidance system disclosed in Patent Document 1 removes the gravity component from the acceleration to improve the accuracy of the calculated acceleration. However, electronic devices may contain noise other than gravity, such as the driving vibration of the electronic device itself or reaction force from the user. In other words, when calculating information corresponding to the movement of an electronic device, a more accurate calculation method that removes noise and other factors from the electronic device is desired.

[0005] The present disclosure has been made in consideration of the problems associated with the conventional techniques, and an object of the present disclosure is to provide a velocity calculation device that can accurately calculate the velocity corresponding to the movement of an electronic device. [Means for solving the problem]

[0006] A speed calculation device according to an aspect of the present disclosure is a speed calculation device that is provided in an electronic device and calculates a speed corresponding to the movement of the electronic device, and includes: a sensor information acquisition unit that acquires sensor information related to acceleration applied to the electronic device from an acceleration sensor; a speed estimation unit that calculates an estimated speed estimated for the movement of the electronic device based on the sensor information; an average speed calculation unit that performs filtering and integration processing on the sensor information to calculate an average speed corresponding to the movement of the electronic device; a relationship information calculation unit that calculates relationship information indicating the correspondence between the estimated speed and the average speed; and a speed determination unit that determines a speed corresponding to the current movement of the electronic device based on the relationship information and the current estimated speed calculated by the speed estimation unit.

[0007] A speed calculation method according to another aspect of the present disclosure is a speed calculation method executed by a computer, which acquires sensor information relating to acceleration acting on an electronic device from an acceleration sensor, calculates an estimated speed for the movement of the electronic device based on the sensor information, performs filtering and integration processing on the sensor information to calculate an average speed corresponding to the movement of the electronic device, calculates relationship information indicating the correspondence between the estimated speed and the average speed, and determines a speed corresponding to the current movement of the electronic device based on the relationship information and the current estimated speed.

[0008] A speed calculation program according to another aspect of the present disclosure causes a computer to perform the following processes: acquire sensor information regarding acceleration acting on an electronic device from an acceleration sensor; calculate an estimated speed for the movement of the electronic device based on the sensor information; perform filtering and integration processing on the sensor information; calculate an average speed corresponding to the movement of the electronic device; calculate relationship information indicating the correspondence between the estimated speed and the average speed; and determine the speed corresponding to the current movement of the electronic device based on the relationship information and the current estimated speed. [Effects of the Invention]

[0009] According to the present disclosure, it is possible to provide a velocity calculation device that can accurately calculate the velocity corresponding to the movement of an electronic device. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic diagram of an electric toothbrush equipped with a speed calculation device according to an embodiment of the present invention. [Figure 2] 1 is a block diagram showing a schematic configuration of a velocity calculation device according to an embodiment of the present invention; [Figure 3] 1 is a block diagram showing a functional configuration of a velocity calculation device according to an embodiment of the present invention; [Figure 4] 5 is a diagram showing an example of a waveform of acceleration acquired by a sensor information acquisition unit according to the embodiment; FIG. [Figure 5] FIG. 2 is a block diagram showing the functional configuration of a speed estimation unit according to the present embodiment. [Figure 6A] FIG. 10 is a diagram showing an example of a waveform of acceleration converted into absolute values ​​by an absolute value processing unit according to the present embodiment. [Figure 6B] 10 is a diagram showing an example of a waveform of acceleration subjected to moving average processing by a first moving average processing unit according to the present embodiment. FIG. [Figure 7] FIG. 2 is a block diagram showing the functional configuration of an average velocity calculation unit according to the present embodiment. [Figure 8A] FIG. 4 is a diagram showing an example of a waveform of acceleration that has been subjected to low-pass filtering by a first low-pass filter according to the present embodiment. [Figure 8B] FIG. 10 is a diagram showing an example of a waveform of acceleration that has been subjected to high-pass processing by the high-pass processing unit according to the embodiment. [Figure 8C] FIG. 4 is a diagram showing an example of a waveform of a velocity calculated by a velocity calculation unit according to the present embodiment. [Figure 8D] FIG. 10 is a diagram showing an example of a waveform of velocity after low-pass processing by the second low-pass processor according to the embodiment. [Figure 8E] FIG. 10 is a diagram showing an example of a waveform of a velocity after moving average processing by a second moving average processing unit according to the present embodiment. [Figure 8F]10A and 10B are diagrams for explaining the process of determining an average speed in an average speed determination processing unit according to the present embodiment. [Figure 9] 4 is a flowchart illustrating an example of processing performed by the velocity calculation device according to the present embodiment. [Figure 10] 10 is a flowchart illustrating an example of a speed estimation process according to the present embodiment. [Figure 11] 10 is a flowchart illustrating an example of an average speed calculation process according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments will be described in detail with reference to the drawings. However, unnecessary detailed description may be omitted. For example, detailed description of already well-known matters or redundant description of substantially the same configuration may be omitted. Note that the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

[0012] (Schematic configuration of velocity calculation device 100) A velocity calculation device 100 according to this embodiment is provided in an electronic device and calculates a velocity corresponding to the movement of the electronic device. Hereinafter, an embodiment in which an electric toothbrush 1 is applied as the electronic device will be described.

[0013] Fig. 1 is a diagram showing the appearance of an electric toothbrush 1 equipped with a speed calculation device 100 according to this embodiment. As shown in Fig. 1, the electric toothbrush 1 includes an activation switch 10 and a speed calculation device 100. In the example shown in Fig. 1, the longitudinal direction of the electric toothbrush 1 (the vertical direction in Fig. 1) is defined as the Y-axis direction. The left-right direction in Fig. 1 is defined as the X-axis direction, and the depth direction in Fig. 1 is defined as the Z-axis direction.

[0014] The electric toothbrush 1 is activated and stopped by the user turning on and off the activation switch 10. The speed calculation device 100 calculates the speed of the movement of the user's hand holding the electric toothbrush 1.

[0015] Fig. 2 is a block diagram showing the configuration of the electric toothbrush 1. As shown in Fig. 2, the electric toothbrush 1 includes a speed calculation device 100, an activation switch 10, and a sensor unit 11. In this embodiment, the sensor unit 11 is configured by an acceleration sensor.

[0016] The speed calculation device 100 includes a control unit 110, a storage unit 120, and an input / output IF 140 (interface). The speed calculation device 100 may also include a communication IF 130. The speed calculation device 100 may be configured as a general-purpose microcomputer including a CPU (control unit 110), a memory (storage unit 120), and the input / output IF 140. In this case, a computer program for causing the microcomputer to function as the speed calculation device 100 may be installed in the microcomputer. By executing the computer program, the microcomputer functions as multiple information processing circuits included in the speed calculation device 100. Note that in this embodiment, an example is shown in which the multiple information processing circuits included in the speed calculation device 100 are realized by software. However, it is also possible to configure the information processing circuits by providing dedicated hardware for executing each of the information processes described below. Alternatively, the multiple information processing circuits may be configured as separate hardware.

[0017] The control unit 110 operates based on a program (not shown) stored in the storage unit 120, and executes the functions shown in Fig. 3. The program is not limited to being stored in the storage unit 120, and may be stored in, for example, a ROM (not shown) or the like within the velocity calculation device 100.

[0018] The storage unit 120 acquires and stores the sensor information acquired by the sensor unit 11 via the input / output IF 140. As described above, the storage unit 120 may also store programs for the functions executed by the control unit 110. The sensor information and programs stored in the storage unit 120 may be configured as physically or logically separated areas in a single storage device. Alternatively, the storage units 120 for each data may be configured in multiple physically different storage devices.

[0019] The communication IF 130 is an interface for communicating between the speed calculation device 100 and various external devices via a wired and / or wireless network. A user may update the control program of the speed calculation device 100 via the communication IF 130. A user may also obtain sensor information stored in the storage unit 120 via the communication IF 130.

[0020] The input / output IF 140 is an interface for transmitting and receiving data, control signals, etc. between the speed calculation device 100 and the activation switch 10 and sensor unit 11 of the electric toothbrush 1. The input / output IF 140 may also function as a component (interface) for the user to exchange data with the speed calculation device 100.

[0021] (Functional configuration of the velocity calculation device 100) FIG. 3 is a block diagram showing the functional configuration of the velocity calculation device 100 according to this embodiment.

[0022] As shown in FIG. 3, the control unit 110 of the speed calculation device 100 has, as its functions, a sensor information acquisition unit 111, a speed estimation unit 112, an average speed calculation unit 113, a relationship information calculation unit 114, a speed determination unit 115, and an output unit 116.

[0023] The sensor information acquisition unit 111 acquires the sensor information of the electric toothbrush 1 acquired by the sensor unit 11 as acceleration information. That is, the sensor information acquisition unit 111 acquires sensor information related to the acceleration acting on the electric toothbrush 1 from the sensor unit 11, which is an acceleration sensor. The sensor information acquisition unit 111 also stores the acquired sensor information in the sensor information DB 121.

[0024] In this embodiment, the sensor information of the acceleration sensor acquired by the sensor information acquisition unit 111 is acceleration information in a predetermined direction. The predetermined direction is, for example, the Y-axis direction shown in Fig. 1, and the acceleration is acquired when the user holds (grabs) the electric toothbrush 1 and brushes the electric toothbrush 1 while moving it in the Y-axis direction, which is the longitudinal direction of the electric toothbrush 1. Note that the predetermined direction of acceleration in the sensor information does not limit the configuration of this embodiment, and may be, for example, acceleration information with respect to acceleration in the X-axis or Z-axis direction shown in Fig. 1.

[0025] FIG. 4 is a diagram showing the waveform of the acceleration of the electric toothbrush 1 acquired by the sensor unit 11. In the diagram shown in FIG. 4, the horizontal axis represents time, and the vertical axis represents the acceleration acquired by the sensor unit 11. As shown in FIG. 4, the acceleration has a certain periodicity in which positive and negative values ​​are repeated in a predetermined direction. For example, in the example shown in FIG. 4, the acceleration waveform is repeated at a cycle of approximately 1.2 seconds. That is, FIG. 4 shows an example in which a user holding the electric toothbrush 1 moves the electric toothbrush 1 back and forth in a predetermined direction at intervals of approximately 1.2 seconds.

[0026] The speed estimation unit 112 estimates the speed of the electric toothbrush 1 based on the acceleration information of the electric toothbrush 1 acquired by the sensor information acquisition unit 111. That is, the speed estimation unit 112 calculates an estimated speed estimated for the movement of the electric toothbrush 1 based on the acceleration information corresponding to the sensor information. The speed estimation unit 112 also stores the calculated estimated speed in the sensor information DB 121 in association with the sensor information corresponding to the calculated estimated speed. Note that the storage location of the estimated speed is not limited to the sensor information DB 121, and the estimated speed may be stored in association with the corresponding sensor information in a memory location different from the sensor information DB 121.

[0027] As shown in FIG. 5, the speed estimation unit 112 further includes, as functions, a first unit conversion processing unit 112a, an absolute value processing unit 112b, a first moving average processing unit 112c, and an estimated cycle average speed determination unit 112d.

[0028] The first unit conversion processing unit 112a converts the acceleration value acquired by the sensor information acquisition unit 111 into the SI unit system (International System of Units). The conversion of the unit system in the first unit conversion processing unit 112a is performed based on the following equation (1): s [n] indicates the acceleration at the nth sample in the acceleration information acquired by the sensor information acquisition unit 111. a[n] indicates the acceleration at the nth sample after unit conversion.

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[0029] The absolute value processing unit 112b performs a process of converting the acceleration (a) converted into the SI unit system by the first unit conversion processing unit 112a into an absolute value. The absolute value processing by the absolute value processing unit 112b is performed in order to obtain the magnitude of the average acceleration per cycle by the first moving average processing unit 112c, which will be described later. FIG. 6A shows the acceleration (a) converted into an absolute value by the absolute value processing unit 112b. a6A, the absolute value processing unit 112b displays the acceleration (a) converted into the SI unit system by the first unit conversion processing unit 112a in a form where the negative part of the acceleration (a) is folded back to the positive side.

[0030] The first moving average processing unit 112c calculates the absolute value of the acceleration (a a ) is calculated over a predicted period of one cycle. That is, the first moving average processing unit 112c calculates the average acceleration per cycle over a predetermined period. The first moving average processing unit 112c performs the process shown in the following equation (2). The overlined a[n] is the acceleration (a m )

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[0031] FIG. 6B is a diagram showing an example of acceleration after the moving average process. In FIG. 6B, the acceleration (a m ) are indicated by dotted lines. In the example shown in Fig. 6B, one section is set to 1.2 seconds, which is the length of one cycle, and 120 samples are used in one cycle. That is, in the example shown in Fig. 6B, the number of samples T per cycle is calculated as 120 in the above formula (2).

[0032] The estimated cycle average speed determination unit 112d calculates the moving average of the acceleration calculated by the first moving average processing unit 112c as the estimated cycle average speed (V e In this embodiment, the estimated cycle average speed determining unit 112d determines the acceleration (a m ) is determined as the estimated cycle average speed. This is based on the characteristic that, for example, when the electric toothbrush 1 is reciprocated in a predetermined direction, the acceleration is approximated by a trigonometric function, and "acceleration ≒ speed." The estimated cycle average speed corresponds to the estimated speed.

[0033] For example, in the example shown in FIG. 6B, the estimated cycle average speed determiner 112d determines the moving average acceleration (a m ) is 2.8 m / s 2 In the case of , the estimated cycle average speed (V e ) is determined as 2.8 m / s. That is, in the example shown in FIG. 6B, the estimated speed is estimated as 2.8 m / s.

[0034] Next, a description will be given of the average speed calculation unit 113. The average speed calculation unit 113 performs filtering and integration on the sensor information to calculate the average speed corresponding to the movement of the electric toothbrush 1.

[0035] 7, average speed calculation unit 113 has, as its functions, second unit conversion processing unit 113a, first low-pass processing unit 113b, high-pass processing unit 113c, and speed calculation unit 113d. Furthermore, average speed calculation unit 113 further has, as its functions, second low-pass processing unit 113e, second moving average processing unit 113f, and average speed determination processing unit 113g.

[0036] The second unit conversion processing unit 113a converts the acceleration acquired by the sensor unit 11 into SI units (International System of Units). The unit conversion processing performed by the second unit conversion processing unit 113a is performed based on the above formula (1), similar to the first unit conversion processing unit 112a described above.

[0037] The first low-pass processing unit 113b converts the acceleration (a s ) is subjected to low-pass processing (low-pass filter processing) as a filter process. In the first low-pass processing unit 113b, general low-pass processing is performed as shown in the following equation (3). Here, k1 is a predetermined coefficient, which can be set according to the characteristics of the electronic device to which the velocity calculation device 100 is applied. lindicates the acceleration performed in the first low-pass processing unit 113b. The first low-pass processing unit 113b performs low-pass processing as a filter process to pass low-frequency components of the acceleration, i.e., removes high-frequency components, thereby making it possible to remove high-frequency noise such as drive noise and reaction force noise of the electric toothbrush 1.

number

[0038] FIG. 8A is a graph showing an example of the results of low-pass filtering performed by first low-pass filtering section 113b.

[0039] The high-pass processing unit 113c processes the acceleration (a l ) is subjected to high-pass processing (high-pass filter processing) as a filter process. In the high-pass processing unit 113c, general high-pass processing is performed as shown in the following equation (4). Here, k2 is a predetermined coefficient, which can be set according to the characteristics of the electronic device to which the velocity calculation device 100 is applied. h indicates the acceleration performed in the high-pass processing unit 113c. The high-pass processing unit 113c performs high-pass processing as a filter process to pass high-frequency components of the acceleration, i.e., removes low-frequency components, thereby making it possible to remove the component of gravity acting on the electric toothbrush 1.

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[0040] FIG. 8B is a graph showing an example of the results of high-pass processing performed by high-pass processor 113c.

[0041] The velocity calculation unit 113d calculates the velocity by integrating the result of the high-pass processing performed by the high-pass processing unit 113c. The velocity calculation unit 113d performs the integration process as shown in the following equation (5). Here, s in equation (5) is the sampling time of the acceleration sensor. For example, if one interval is 1.2 seconds and there are 120 samples, the sampling time s is 10 ms. V i indicates the velocity calculated by the velocity calculation unit 113d.

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[0042] FIG. 8C shows the velocity (V i ) is a graph showing an example of

[0043] The second low-pass filter 113e calculates the velocity (V i ) is subjected to low-pass processing (low-pass filter processing) as a filter process. In the second low-pass processing unit 113e, general low-pass processing is performed as shown in the following equation (6). Here, k3 is a predetermined coefficient, which can be set according to the characteristics of the electronic device to which the velocity calculation device 100 is applied. V l indicates the velocity performed in second low-pass processing section 113e. Second low-pass processing section 113e performs preprocessing of data for average velocity determination processing section 113g, which will be described later.

number

[0044] 8D is a graph showing an example of the result of low-pass filtering performed by the second low-pass filter 113e. In FIG. 8D, the velocity (V l ) has a waveform shown by a dotted line. In order to clearly show the result of the low-pass processing in the second low-pass processor 113e, the velocity (V i ) waveform shown in Figure 8Ci ) in different cases i ) is shown as an example.

[0045] The second moving average processor 113f calculates the velocity (V l ) is subjected to moving average processing within a predicted one cycle period. Specifically, the processing shown in the following equation (7) is performed.

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[0046] 8E is a diagram showing an example of the speed at which the moving average process is performed by the second moving average processor 113f. In FIG. 8E, the speed at which the moving average process is performed (V m ) are shown with dashed lines.

[0047] The average speed determination processing unit 113g determines the moving average (V m ), the average speed between the maximum speed and the minimum speed is calculated. That is, the average speed determination processing unit 113g calculates the average speed between the maximum speed and the minimum speed of the previous cycle. Specifically, the average speed is calculated by the following equation (8). The overlined V[n] indicates the average speed in the cycle at the nth sample time. n max indicates the nth sample of the maximum speed immediately before the extreme value (upper or lower limit) of the speed (moving average). min indicates the nth sample of the minimum speed immediately before the extreme value (upper or lower limit) of the speed (moving average).

number

[0048] 8F is a diagram for explaining the calculation process of the average speed in the average speed determination processing unit 113g. At the timing (1) in FIG. 8F, the average speed determination processing unit 113g calculates the maximum speed at the sample point n max and the minimum value, sample point nmin The average speed A is measured. This average speed A is recognized as the speed of the previous cycle at the lower limit of the moving average shown in FIG. 8F (2).

[0049] Similarly, at timing (3) in FIG. 8F, the average speed determination processing unit 113g determines the minimum speed at the sample point n min and the maximum value of sample point n max The average speed B is measured. This average speed B is recognized as the speed of the previous cycle at the upper limit of the moving average shown in FIG. 8F (4).

[0050] In this way, by performing the moving average process in the second moving average processor 113f, the result of the moving average process appears with a time delay relative to the time corresponding to the actual speed, which makes it easier to associate the average speed in a predetermined section with the speed obtained by the moving average process, and the average speed determination processor 113g can calculate the average speed with higher accuracy.

[0051] The relationship information calculation unit 114 calculates the estimated average cycle speed (V) of the past cycle. e ) and the average speed (overlined V) calculated by the average speed determination processing unit 113g, the relationship information calculation unit 114 calculates relationship information indicating the correspondence between the estimated speed (overlined Ve) and the average speed (overlined V). The relationship information calculation unit 114 calculates the estimated cycle average speed (estimated speed, overlined V) of the past cycle by the least squares method. e ) and the cycle average speed (overlined V) calculated by the average speed determination processing unit 113g. This enables the speed calculation device 100 to calculate a relational expression (relationship information) that more accurately indicates the correspondence relationship between the estimated speed and the average speed. In this embodiment, the relational expression corresponds to the relationship information.

[0052] The relational expression calculated by the relational information calculation unit 114 is determined by equation (9), where α and β are coefficients in the relational expression.

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[0053] α and β in the above formula (9) are determined by the following formulas (10) and (11).

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[0054] The speed determination unit 115 determines the cycle average speed based on α, β and the relational expression calculated by the relational information calculation unit 114. Specifically, the speed determination unit 115 determines the speed corresponding to the current movement of the electric toothbrush 1 based on the relational expression, which is the relational information, and the current estimated speed calculated by the speed estimation unit 112. That is, the current estimated cycle average speed (overlined V) estimated by the speed estimation unit 112 is e [n now ]) into the above equation (9), a more accurate velocity (overlined V[n now ]) can be determined.

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[0055] The output unit 116 outputs the speed (overlined V[n now ]) and outputs a predetermined judgment result. Here, the predetermined judgment result is the determined velocity (overlined V[n now ]) may be the result of determining whether there is any problem in using the electric toothbrush 1. For example, the output unit 116 may be configured to output the determination result using a predetermined application (not shown).

[0056] (Processing flow of the velocity calculation device 100) Next, the velocity calculation process (velocity calculation method) in the velocity calculation device 100 will be described with reference to the flowcharts of Figs. 9 to 11. The series of operations of the velocity calculation device 100 shown in the flowcharts of Figs. 9 to 11 starts when the activation switch 10 is turned on to start up the electric toothbrush 1, and ends when the activation switch 10 is turned off. The flowcharts shown in Figs. 9 to 11 also end when the power switch (not shown) is turned off or an interrupt occurs to end the process. In the following description of the flowcharts, the same content as that described in the above description of the velocity calculation device 100 will be omitted or simplified.

[0057] In step S901, the control unit 110 determines whether the activation switch 10 is on. If the control unit 110 determines in step S901 that the activation switch 10 is on (step S901: YES), the process proceeds to step S902. On the other hand, if the control unit 110 determines in step S901 that the activation switch 10 is not on (step S901: NO), the process returns to step S901. That is, the control unit 110 repeatedly performs the process of step S901 until the activation switch 10 is on.

[0058] In step S902, the sensor information acquisition unit 111 acquires the sensor information of the electric toothbrush 1 acquired by the sensor unit 11 as acceleration information. In this embodiment, the sensor information of the acceleration sensor acquired by the sensor information acquisition unit 111 is acceleration information in a predetermined direction. Next, the process proceeds to step S903.

[0059] In step S903, the speed estimation unit 112 estimates the speed of the electric toothbrush 1 based on the acceleration information of the electric toothbrush 1 acquired by the sensor information acquisition unit 111. That is, the speed estimation unit 112 calculates an estimated speed of the movement of the electric toothbrush 1 based on the acceleration information corresponding to the sensor information. Specifically, the speed estimation unit 112 estimates the speed through the processing shown in the flowchart of Fig. 10. Details of the processing of the flowchart shown in Fig. 10 will be described later. Next, the processing proceeds to step S904.

[0060] In step S904, the average speed calculation unit 113 performs filtering and integration on the sensor information to calculate the average speed corresponding to the movement of the electric toothbrush 1. Specifically, by the processing shown in the flowchart of Fig. 11, the average speed calculation unit 113 performs filtering and integration on the sensor information to calculate the average speed corresponding to the movement of the electric toothbrush 1. Details of the processing in the flowchart shown in Fig. 11 will be described later. Next, the processing proceeds to step S905.

[0061] In step S905, the relationship information calculation unit 114 calculates the estimated average cycle speed (V e ) and the average speed (overlined V) calculated by the average speed determination processing unit 113g, the relationship information calculation unit 114 calculates relationship information indicating the correspondence between the estimated speed (overlined Ve) and the average speed (overlined V). The relationship information calculation unit 114 calculates the estimated cycle average speed (estimated speed, overlined V) of the past cycle by the least squares method. e ) and the cycle average speed (overlined V) calculated by the average speed determination processing unit 113g. This enables the speed calculation device 100 to calculate a relational expression (relationship information) that more accurately indicates the correspondence relationship between the estimated speed and the average speed. In this embodiment, the relational expression corresponds to the relationship information. Next, the process proceeds to step S906.

[0062] In step S906, the speed determination unit 115 determines the cycle average speed based on α, β and the relational expression calculated by the relationship information calculation unit 114. Specifically, the speed determination unit 115 determines the speed corresponding to the current movement of the electric toothbrush 1 based on the relational expression, which is the relationship information, and the current estimated speed calculated by the speed estimation unit 112. That is, the current estimated cycle average speed (overlined V) estimated by the speed estimation unit 112 is used as the speed determination unit 115. e [n now ]) into the above equation (9), a more accurate velocity (overlined V[n now ]) can be confirmed. Next, the process proceeds to step S907.

[0063] In step S907, the control unit 110 determines whether the activation switch 10 is off. If the control unit 110 determines in step S907 that the activation switch 10 is off (step S907: YES), the process ends. On the other hand, if the control unit 110 determines in step S907 that the activation switch 10 is not off (step S907: NO), the process returns to step S902, and the process from step S902 is repeated.

[0064] (Speed ​​estimation processing) Next, the speed estimation process in step S903 in FIG. 9 will be described with reference to the flowchart in FIG.

[0065] In step S1001, first unit conversion processing unit 112a converts the acceleration value acquired by sensor information acquisition unit 111 into SI units (International System of Units). The unit conversion in first unit conversion processing unit 112a is performed based on the above-mentioned formula (1). Next, the process proceeds to step S1002.

[0066] In step S1002, the absolute value processing unit 112b converts the acceleration (a) converted to SI units in the first unit conversion processing unit 112a into an absolute value. The absolute value processing in the absolute value processing unit 112b is performed so that the magnitude of the average acceleration per cycle can be calculated in the first moving average processing unit 112c. Next, the process proceeds to step S1003.

[0067] In step S1003, the first moving average processing unit 112c calculates the absolute value of the acceleration (a a ) and calculates a moving average over a predicted one cycle interval. That is, the first moving average processing unit 112c calculates the average acceleration per cycle over a predetermined interval. The first moving average processing unit 112c performs the process shown in the above-mentioned equation (2). Next, the process proceeds to step S1004.

[0068] In step S1004, the estimated cycle average speed determination unit 112d calculates the moving average of the acceleration calculated by the first moving average processing unit 112c as the estimated cycle average speed (estimated speed, overlined V e In this embodiment, the estimated cycle average speed determining unit 112d determines the acceleration (a m ) is determined as the estimated cycle average speed (estimated speed). This is based on the characteristic that, for example, when the electric toothbrush 1 is reciprocated in a predetermined direction, the acceleration is approximated by a trigonometric function, and "acceleration ≒ speed." Then, the process returns to step S903 in the flowchart shown in FIG. 9.

[0069] (Average speed calculation process) Next, the average speed calculation process in step S904 in FIG. 9 will be described with reference to the flowchart in FIG.

[0070] In step S1101, the second unit conversion processing unit 113a converts the acceleration acquired by the sensor unit 11 into SI units (International System of Units). The unit conversion processing performed by the second unit conversion processing unit 113a is performed based on the above formula (1), similar to the first unit conversion processing unit 112a. Next, the processing proceeds to step S1102.

[0071] In step S1102, the first low-pass filter 113b converts the acceleration (a s ) is subjected to low-pass processing. In first low-pass processing section 113b, general low-pass processing is performed as shown in the above-mentioned equation (3). In step S1102, first low-pass processing section 113b passes the low-frequency components of the acceleration, i.e., removes the high-frequency components, thereby making it possible to remove high-frequency noise such as that due to the driving force and reaction force of electric toothbrush 1. Next, the process proceeds to step S1103.

[0072] In step S1103, the high-pass processing unit 113c calculates the acceleration (a l ) is subjected to high-pass processing. In the high-pass processing unit 113c, general high-pass processing is performed as shown in the above-mentioned equation (4). In step S1103, the high-pass processing unit 113c passes the high-frequency components of the acceleration, i.e., removes the low-frequency components, thereby making it possible to remove the components of gravity acting on the electric toothbrush 1. Next, the process proceeds to step S1104.

[0073] In step S1104, velocity calculation unit 113d calculates velocity by integrating the result of high-pass filtering performed by high-pass filtering unit 113c. Velocity calculation unit 113d performs integration as shown in equation (5) above. Next, the process proceeds to step S1105.

[0074] In step S1105, the second low-pass processing unit 113e calculates the velocity (V i) is subjected to low-pass filtering. In second low-pass filtering section 113e, general low-pass filtering is performed as shown in equation (6) above. Next, the process proceeds to step S1106.

[0075] In step S1106, the second moving average processor 113f calculates the velocity (V l ) is subjected to moving average processing within a predicted one cycle period. Specifically, the processing shown in the above-mentioned equation (7) is performed. Next, the processing proceeds to step S1107.

[0076] In step S1107, the average speed determination processing unit 113g determines the moving average (V m ), the average speed between the maximum speed and the minimum speed is calculated. Specifically, the average speed is calculated using the above-mentioned equation (8). Thereafter, the process returns to step S904 in the flowchart shown in FIG.

[0077] As described above, the speed calculation device 100 includes a sensor information acquisition unit 111, a speed estimation unit 112, an average speed calculation unit 113, a relationship information calculation unit 114, and a speed determination unit 115. The sensor information acquisition unit 111 acquires sensor information related to the acceleration acting on the electronic device from an acceleration sensor. The speed estimation unit 112 calculates an estimated speed that is estimated for the movement of the electronic device based on the sensor information. The average speed calculation unit 113 performs filtering and integration processes on the sensor information to calculate an average speed corresponding to the movement of the electronic device. The relationship information calculation unit 114 calculates relationship information that indicates the correspondence between the estimated speed and the average speed. The speed determination unit 115 determines a speed corresponding to the current movement of the electronic device based on the relationship information and the current estimated speed calculated by the speed estimation unit 112.

[0078] That is, the velocity calculation device 100 calculates the velocity corresponding to the movement of the electronic device using relationship information indicating the correspondence relationship between the estimated velocity estimated for the movement of the electronic device and the average velocity corresponding to the movement of the electronic device. This allows the velocity calculation device 100 to calculate the velocity corresponding to the movement of the electronic device more accurately than simply calculating the estimated velocity estimated for the movement of the electronic device as the velocity corresponding to the movement of the electronic device.

[0079] Furthermore, the filtering process of the average velocity calculation unit 113 of the velocity calculation device 100 may include low-pass filtering to remove high-frequency components. This enables the velocity calculation device 100 to remove high-frequency noise such as that due to the driving force or reaction force of the electronic device when calculating the velocity corresponding to the movement of the electronic device.

[0080] Furthermore, the filtering process of the average velocity calculation unit 113 of the velocity calculation device 100 may further include high-pass filtering to remove low-frequency components. This allows the velocity calculation device 100 to remove the component of gravity acting on the electronic device by removing low-frequency components in calculating the velocity corresponding to the movement of the electronic device.

[0081] Furthermore, the relationship information calculation unit 114 of the velocity calculation device 100 may calculate relationship information indicating the correspondence relationship between the estimated velocity estimated for the movement of the electronic device and the average velocity corresponding to the movement of the electronic device by the least squares method. This enables the velocity calculation device 100 to calculate relationship information indicating the correspondence relationship between the estimated velocity and the average velocity more accurately.

[0082] Furthermore, the average speed calculation unit 113 of the speed calculation device 100 may calculate the average speed by further performing a moving average process. This causes the result of the moving average process to appear with a delay from the time corresponding to the actual speed, making it easier to associate the average speed in a predetermined section with the speed obtained by the moving average process. This allows the speed calculation device 100 to further improve the accuracy in calculating the average speed.

[0083] (Other embodiments) Although the present embodiment has been described above, the embodiment is not limited to these, and various modifications are possible within the scope of the gist of the embodiment. It is also possible to combine some or all of the various embodiments to create a new embodiment. In other words, the above-described embodiment is intended to illustrate the technology of the present disclosure, and various modifications, substitutions, additions, omissions, etc. may be made within the scope of the claims or their equivalents.

[0084] In the above-described embodiment, the electronic device is an electric toothbrush 1. The velocity calculation device 100 according to this embodiment may be applied to, for example, an iron or an electric shaver as a device for determining the hand movement of a user using the electronic device. In this case, the interval of one cycle, which was set to 1.2 seconds in the case of the electric toothbrush 1 described above, may be set to a time shorter or longer than 1.2 seconds to suit the electronic device. Furthermore, application of the velocity calculation device 100 is not limited to electronic devices held by the user's hand. For example, an electronic device to which the velocity calculation device 100 can be applied may be one worn on the user's body. This makes it possible to realize a velocity calculation device 100 that can determine whether the user's body movement is appropriate for a specific purpose.

[0085] Furthermore, a computer program (speed calculation program) that causes a computer to execute the above-described speed calculation method and a computer-readable recording medium on which the program is recorded are included within the scope of this embodiment. Any type of computer-readable recording medium may be used. Furthermore, the above-described computer program is not limited to being recorded on the above-described recording medium, and may be transmitted via a telecommunications line, a wireless or wired communication line, a network such as the Internet, or the like.

[0086] The following describes the features of the velocity calculation device 100, velocity calculation method, and velocity calculation program according to this embodiment.

[0087] (1) A velocity calculation device 100 that is provided in an electronic device and calculates a velocity corresponding to the movement of the electronic device has the following configuration. (i) The electronic device includes a sensor information acquisition unit 111 that acquires sensor information relating to acceleration applied to the electronic device from an acceleration sensor. (ii) A speed estimation unit 112 is included that calculates an estimated speed of the movement of the electronic device based on sensor information. (iii) An average speed calculation unit 113 is included which performs filtering and integration processing on the sensor information and calculates an average speed corresponding to the movement of the electronic device. (iv) A relationship information calculation unit 114 is included that calculates relationship information indicating the correspondence between the estimated speed and the average speed. (v) The device includes a speed determination unit 115 that determines a speed corresponding to the current movement of the electronic device based on the relationship information and the current estimated speed calculated by the speed estimation unit 112.

[0088] According to the present disclosure, the velocity calculation device 100 calculates the velocity corresponding to the movement of the electronic device using relationship information indicating the correspondence relationship between the estimated velocity estimated for the movement of the electronic device and the average velocity corresponding to the movement of the electronic device. This enables the velocity calculation device 100 to calculate the velocity corresponding to the movement of the electronic device more accurately than simply calculating the estimated velocity estimated for the movement of the electronic device as the velocity corresponding to the movement of the electronic device.

[0089] (2) The filtering process may include low-pass filtering to remove high-frequency components.

[0090] According to the present disclosure, the velocity calculation device 100 can remove high-frequency noise such as that due to the driving force or reaction force of the electronic device when calculating the velocity corresponding to the movement of the electronic device.

[0091] (3) The filtering process may further include high-pass filtering to remove low-frequency components.

[0092] According to the present disclosure, the velocity calculation device 100 can remove the component of gravity acting on the electronic device by removing low-frequency components when calculating the velocity corresponding to the movement of the electronic device.

[0093] (4) The relationship information calculation unit 114 may calculate the relationship information by the least squares method.

[0094] According to the present disclosure, the speed calculation device 100 can calculate relationship information that more accurately indicates the correspondence relationship between the estimated speed and the average speed.

[0095] (5) The average speed calculation unit 113 may further calculate the average speed by performing a moving average process.

[0096] According to the present disclosure, the speed calculation device 100 makes it easy to associate the average speed in a predetermined section with the speed obtained by the moving average process, since the result of the moving average process appears with a time delay relative to the actual speed. As a result, the speed calculation device 100 can calculate the average speed with higher accuracy.

[0097] (6) A speed calculation method executed by a computer includes the following steps. (i) The process includes acquiring sensor information relating to the acceleration applied to the electronic device from an acceleration sensor. (ii) The process includes a process of calculating an estimated speed of the movement of the electronic device based on the sensor information. (iii) The processing includes filtering and integrating the sensor information to calculate an average speed corresponding to the movement of the electronic device. (iv) The process includes a process of calculating relationship information indicating the correspondence between the estimated speed and the average speed. (v) determining a speed corresponding to the current movement of the electronic device based on the relationship information and the current estimated speed;

[0098] According to the present disclosure, the velocity calculation method calculates the velocity corresponding to the movement of the electronic device using relationship information indicating the correspondence relationship between an estimated velocity estimated for the movement of the electronic device and an average velocity corresponding to the movement of the electronic device. This makes it possible to calculate the velocity corresponding to the movement of the electronic device more accurately than simply calculating the estimated velocity estimated for the movement of the electronic device as the velocity corresponding to the movement of the electronic device.

[0099] (7) A speed calculation program to be executed by a computer has the following processes. (i) The process includes acquiring sensor information relating to the acceleration applied to the electronic device from an acceleration sensor. (ii) The process includes a process of calculating an estimated speed of the movement of the electronic device based on the sensor information. (iii) The processing includes filtering and integrating the sensor information to calculate an average speed corresponding to the movement of the electronic device. (iv) The process includes a process of calculating relationship information indicating the correspondence between the estimated speed and the average speed. (v) determining a speed corresponding to the current movement of the electronic device based on the relationship information and the current estimated speed;

[0100] According to the present disclosure, a speed calculation program calculates a speed corresponding to the movement of an electronic device using relationship information indicating a correspondence relationship between an estimated speed estimated for the movement of the electronic device and an average speed corresponding to the movement of the electronic device. This enables the speed calculation program to calculate a speed corresponding to the movement of the electronic device more accurately than simply calculating an estimated speed estimated for the movement of the electronic device as the speed corresponding to the movement of the electronic device. [Industrial Applicability]

[0101] The present disclosure is applicable to electronic devices that a user holds and moves in a predetermined direction, such as electric toothbrushes, electric shavers, and irons. [Explanation of symbols]

[0102] 1 electric toothbrush 10. Operation switch 11 Sensor section 100 Speed ​​calculation device 111 Sensor information acquisition unit 112 Speed ​​estimation part 113 Average speed calculation section 114 Relationship Information Calculation Unit 115 Speed ​​determination section 116 Output section 121 Sensor Information DB

Claims

1. A velocity calculation device provided in an electronic device and calculating a velocity corresponding to a movement of the electronic device, a sensor information acquisition unit that acquires sensor information relating to acceleration applied to the electronic device from an acceleration sensor; a speed estimation unit that calculates an estimated speed of the movement of the electronic device based on the sensor information; an average speed calculation unit that performs filtering and integration on the sensor information to calculate an average speed corresponding to the movement of the electronic device; a relationship information calculation unit that calculates relationship information indicating a correspondence relationship between the estimated speed and the average speed based on the past estimated speed and the past average speed; a speed determination unit that determines the speed corresponding to the current movement of the electronic device based on the relationship information and the current estimated speed calculated by the speed estimation unit.

2. The velocity calculation device according to claim 1 , wherein the filtering process includes low-pass filtering that removes high-frequency components.

3. The velocity calculation device according to claim 2 , wherein the filtering process further includes high-pass filtering that removes low-frequency components.

4. The velocity calculation device according to claim 1 , wherein the relationship information calculation unit calculates the relationship information by a least squares method.

5. The velocity calculation device according to claim 1 , wherein the average velocity calculation unit calculates the average velocity by further performing a moving average process.

6. 1. A computer-implemented method for calculating velocity, comprising: Acquires sensor information relating to acceleration applied to the electronic device from an acceleration sensor; calculating an estimated speed of the movement of the electronic device based on the sensor information; filtering and integrating the sensor information to calculate an average velocity corresponding to the movement of the electronic device; calculating relationship information indicating a correspondence relationship between the estimated speed and the average speed based on the past estimated speed and the past average speed; A speed calculation method for determining a speed corresponding to a current movement of the electronic device based on the relationship information and the current estimated speed.

7. Acquires sensor information relating to acceleration applied to the electronic device from an acceleration sensor; calculating an estimated speed of the movement of the electronic device based on the sensor information; filtering and integrating the sensor information to calculate an average velocity corresponding to the movement of the electronic device; calculating relationship information indicating a correspondence relationship between the estimated speed and the average speed based on the past estimated speed and the past average speed; A speed calculation program that causes a computer to execute a process of determining a speed corresponding to the current movement of the electronic device based on the relationship information and the current estimated speed.

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