JP6603844B2 - Sensor device - Google Patents

Description

  The present invention relates to a sensor device for measuring a pitcher's pitching motion in baseball or the like.

  In recent years, IoT (Internet of Things) has been developed and spread in Japan and the world market. A high-performance one-chip microcomputer reduced in size and weight and a sensor connected to the microcomputer are embedded in various articles to acquire various environmental information. The acquired environmental information is output to various computer resources, and the computer resources analyze the information. Such IoT development extends to the sports world.

US Pat. No. 5,941,779

In the sports world, an attempt has been made to measure the movement of a ball by embedding a microcomputer and a sensor in the ball.
Since the present invention to be described later is a technique for embedding a microcomputer in a hard baseball, a conventional baseball will be described below as an example of a hard baseball.
The technical idea of embedding a microcomputer and a sensor in a ball such as a baseball or golf ball has been proposed for a long time. However, there is still no definitive technology on how to supply power to the microcomputer embedded in the ball and how to turn it on / off. .

  If the ball is thrown straight, it must go straight. That is, the center of gravity of the ball should not be off center. For this reason, the technique of providing a power switch on the surface of the ball cannot be naturally adopted. Moreover, the manufacturing process of a hard baseball includes a process of winding a wool around a central core. For this reason, it is extremely difficult to provide something that exposes the surface of the ball from the central core. For the same reason, an optical sensor such as a phototransistor or a photodiode must be provided on the surface of the ball as in the case of the mechanical switch.

Since the ball is thick, it is not realistic to supply power using the magnetic force from the outside of the ball. Therefore, the primary battery is encapsulated and used in a disposable form that is used until the primary battery is completely consumed. Although it is not impossible to instruct power-on from the outside in a non-contact manner using magnetic force, it is not simple because a device dedicated to power-on instruction is required.
In addition, it is conceivable to use a radio wave to contact the power supply on / off in a non-contact manner, but since the power must be supplied to the communication module inside the ball even in the power save mode, battery consumption is reduced. Intense and impractical.
As described above, it has been very difficult to solve the technical problem of instructing power-on in a hard baseball.

  The present invention has been made in view of such a situation, and an object thereof is to provide a sensor device that can easily instruct power-on without using any external device.

  In order to solve the above-described problems, a sensor device according to the present invention includes an electronic switch that controls the supply of power to a load, an activation acceleration sensor that detects acceleration in three axes and transmits acceleration data, and an activation acceleration sensor An absolute value summing unit that converts the X-axis acceleration data, Y-axis acceleration data, and Z-axis acceleration data obtained from the above data into absolute values and adds them together, and outputs a combined acceleration absolute value. Furthermore, a comparator that compares the absolute value of the total acceleration with a free fall detection threshold value that is below the gravitational acceleration of the earth, and that the comparator indicates that the total acceleration absolute value is less than the free fall detection threshold value for a predetermined time interval or more. In response to the detection, a power supply control unit for turning on the electronic switch is provided.

According to the present invention, it is possible to provide a sensor device that can easily instruct power-on without using any external device.
Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

It is the schematic which shows a mode that the pitcher of a baseball throws the pitching movement measuring device which concerns on embodiment of this invention. It is the outline figure which shows the external view of a pitching movement measuring device, the sectional view which shows the state which cut the pitching movement measuring device, and the core. It is a block diagram which shows the hardware constitutions of a pitching movement measuring device, and a circuit diagram which shows the relationship between a power supply and load. It is a block diagram which shows the software function regarding power-on operation | movement of a pitching operation measurement apparatus. It is a flowchart which shows the flow of operation | movement of the software regarding a power-on operation | movement of a pitching operation | movement measuring device. It is a graph which shows the change of the total acceleration absolute value obtained from the acceleration sensor for starting when the program for measurement is written in the pitching movement measuring device and the pitching movement measuring device is actually thrown up right above.

  In order to realize the throwing motion measurement device according to the embodiment of the present invention, the inventor “throws the ball straight up” as a method for instructing the throwing motion measurement device to turn on the power without using light, magnetism, or radio waves. It has been conceived that a power-on instruction is given by detecting the motion ", that is, giving a free fall state. If the state of free fall is detected, it is possible to give an instruction to turn on the power to the pitching movement measuring device without using a special instrument.

[Appearance and Internal Structure of Throwing Motion Measuring Device 101]
FIG. 1A is a schematic diagram illustrating a setup motion state for the pitcher 102 to throw the pitching motion measuring device 101 as a usage mode of the pitching motion measuring device 101 according to the embodiment of the present invention.
FIG. 1B is a schematic diagram illustrating a state in which the pitcher 102 has thrown the pitching motion measuring device 101.
As can be seen from FIGS. 1A and 1B, the pitching motion measuring apparatus 101 according to the embodiment of the present invention has a function of measuring the motion of the pitcher 102 throwing a hard baseball.

FIG. 2A is an external view of the pitching movement measuring apparatus 101. FIG.
FIG. 2B is a cross-sectional view showing a state in which the pitching motion measuring device 101 is cut into a circle.
FIG. 2C is a schematic diagram showing the core portion 204 of the pitching movement measuring apparatus 101.
The outer skin 201 of the pitching movement measuring device 101 is the same cowhide as the hard baseball. A cotton yarn layer 202 and a yarn layer 203 are present directly under the outer skin 201. The cotton yarn layer 202 and the wool yarn layer 203 have exactly the same specifications as the hard baseball. A core portion 204 in which an electronic circuit such as a microcomputer that realizes the function of the pitching movement measuring device 101 is enclosed is further inside the yarn layer 203.
That is, the pitching movement measuring apparatus 101 according to the embodiment of the present invention has the same appearance as the hard baseball, and is manufactured by the same manufacturing process as the hard baseball except for the core portion 204.
The core portion 204 encloses a printed circuit board 205 on which a button type battery such as CR2032, a one-chip microcomputer, and a sensor are mounted.
Since the core portion 204 is located at the center portion of the ball, even if the center of gravity is slightly shifted, the pitching operation of the pitcher 102 is hardly adversely affected and can be thrown almost straight.

[Hardware Configuration of Throwing Movement Measuring Device 101]
FIG. 3A is a block diagram illustrating a hardware configuration of the pitching movement measuring apparatus 101.
In the one-chip microcomputer 301, a CPU 303, a ROM 304, a RAM 305, and a nonvolatile storage 306 that are arithmetic devices are connected to a bus 302. In addition to this, the bus 302 includes a short-range wireless communication unit 307 for performing wireless communication with an external personal computer in accordance with the Bluetooth (registered trademark) Low Energy standard, a serial interface 308 such as I2C, a system clock 309, and a counter 310. The driver 311 is connected.
The serial interface 308 is connected to a starting acceleration sensor 312, a six-axis sensor 313, and a geomagnetic sensor 314.
The driver 311 is connected to the gate of an N-channel MOSFET 315 that is an electronic switch.

The system clock 309 generates an operation clock necessary for the one-chip microcomputer 301 including the CPU 303 to operate. At this time, control is performed so that the frequency of the operation clock to be output is changed between when the one-chip microcomputer 301 is in the power save mode and in the normal operation mode.
In other words, the system clock 309 in the power save mode generates a low-frequency operation clock that realizes a minimum calculation capability necessary for calculating data of a starting acceleration sensor 312 described later.
In addition, the system clock 309 in the normal operation mode has a high frequency that realizes the computing power necessary for operating the short-range wireless communication unit 307, the six-axis sensor 313, and the geomagnetic sensor 314 and communicating with an external personal computer. Generate an operation clock.

The startup acceleration sensor 312 is a sensor that detects triaxial acceleration and sends digital acceleration data. This starting acceleration sensor 312 has lower power consumption than a 6-axis sensor 313 described later, and therefore, the resolution of data output from the 6-axis sensor 313 is lower.
The 6-axis sensor 313 is a sensor that detects 6-axis acceleration and sends digital acceleration data and angular acceleration data. This outputs data of acceleration and angular acceleration resulting from the pitching motion of the pitcher 102.

The geomagnetic sensor 314 is a sensor that detects changes in triaxial geomagnetism and transmits digital data. This outputs data indicating the direction of geomagnetism that changes due to the pitching operation of the pitcher 102 (the attitude of the geomagnetic sensor 314 itself).
The MOSFET 315 is a low-side switch for controlling the supply of power to the load Z316. The load Z316 corresponds to a 6-axis sensor 313 and a geomagnetic sensor 314 as shown in FIG. 3B. Note that a high-side switch may be configured using a P-channel MOSFET instead of the N-channel MOSFET 315.

FIG. 3B is a circuit diagram showing the relationship between the power supply and the load Z316 of the pitching movement measuring apparatus 101.
The starting acceleration sensor 312 and the one-chip microcomputer 301 are connected to the battery 317 and are always supplied with electric power. On the other hand, the 6-axis sensor 313 and the geomagnetic sensor 314 are ON / OFF controlled by the MOSFET 315. Therefore, power is supplied to the six-axis sensor 313 and the geomagnetic sensor 314 only when the MOSFET 315 is turned on.

[Software Function of Throwing Movement Measuring Device 101]
FIG. 4 is a block diagram showing software functions related to the power-on operation of the pitching movement measuring apparatus 101. Note that the block diagram shown in FIG. 4 includes a part of software functions equivalently described by hardware symbols. Therefore, the hardware is not necessarily used.
In the sleep mode, the one-chip microcomputer 301 operates as the activation operation detection unit 401.

The startup acceleration sensor 312 outputs X-axis acceleration data, Y-axis acceleration data, and Z-axis acceleration data, which are digital acceleration data, for the three axes of the X axis, the Y axis, and the Z axis.
The X-axis acceleration data, the Y-axis acceleration data, and the Z-axis acceleration data are input to the absolute value summation unit 402. The absolute value summation unit 402 converts each of the X-axis acceleration data, Y-axis acceleration data, and Z-axis acceleration data into absolute values and sums the data, and outputs a summed acceleration absolute value.
This total acceleration absolute value is supplied to the negative terminal of the comparator 403. A free fall detection threshold 404 below 1.0 G corresponding to the gravitational acceleration of the earth is supplied to the positive terminal of the comparator 403. For example, 0.3G. Therefore, the comparator 403 outputs a logical true when the combined acceleration absolute value becomes a value less than the free fall detection threshold 404.

The output logic value of the comparator 403 is input to the reset terminal of the counter 310. The counter 310 counts clock pulses output from the sample clock 405 during a period when the logical value of the reset terminal is false. In FIG. 4, since the reset terminal of the counter 310 is negative logic, the reset becomes invalid and the counting function of the counter 310 is validated when the output logic value of the comparator 403 is at a high potential.
When the value obtained by counting the clock pulses output from the sample clock 405 reaches a predetermined count value set in advance, the counter 310 outputs logic true. The predetermined count value is “15”, for example.

The sample clock 405 outputs a clock pulse to the counter 310 and the command issuing unit 406. The frequency of the clock pulse is, for example, 25 Hz.
The command issuing unit 406 issues a command for instructing acceleration measurement to the activation acceleration sensor 312. This command is issued at a time interval that realizes the lowest resolution that can detect that the free fall state has continued for a predetermined time or more. Therefore, this time interval is determined by the sample clock 405.

When the counter 310 outputs logic true, the power supply control unit 407 connected to the output terminal of the counter 310 is turned on.
The power supply control unit 407 changes the frequency of the clock output by the system clock 309 from a low frequency to a high frequency in response to the counter 310 outputting logic true. At the same time, the power supply control unit 407 turns on the short-range wireless communication unit 307. Further, the power supply control unit 407 controls the MOSFET 315 to be on. Thus, the pitching movement measuring apparatus 101 shifts to the normal operation mode.

[Flow of start-up process of pitching motion measuring apparatus 101]
FIG. 5 is a flowchart showing the flow of software operations related to the power-on operation of the pitching motion measurement apparatus 101.
When the process is started (S501), the activation operation detection unit 401 first sets the operation mode to the power save mode (S502).
Next, the activation operation detection unit 401 checks the throwing operation (S503). The throwing operation check is a logical output of the counter 310 in FIG.
When the counter 310 outputs a logic false, that is, when the activation operation detection unit 401 cannot detect the throwing operation (NO in S504), the activation operation detection unit 401 looks at the logic output of the counter 310 again, The check of the throwing operation is repeated (S503).

In step S504, when the counter 310 outputs logic true, that is, when the activation operation detection unit 401 can detect the throwing operation (YES in S504), the activation operation detection unit 401 sets the operation mode to the normal operation mode. (S505). Next, the MOSFET 315 and the short-range wireless communication unit 307 are turned on through the power supply control unit 407, and the clock frequency of the system clock 309 is changed to a frequency for normal operation (S506).

Next, the activation operation detection unit 401 checks power save conditions (S507). The power save condition is a condition for determining that the throwing motion measuring apparatus 101 should be left stationary and that the power save mode should be entered. This condition is, for example, maintaining a state where the combined acceleration absolute value of the activation acceleration sensor 312 is less than 1.2 G (1.2 times the gravitational acceleration of the earth) for 60 seconds. That is, it is a condition for automatically shifting to the power-off state (strictly, in the power save mode) when it is not used.
When the power saving condition is not satisfied (NO in S508), the activation operation detection unit 401 repeats the power saving condition check again (S507).

In step S508, when the power save condition is satisfied (YES in S508), the activation operation detection unit 401 sets the operation mode to the power save mode (S502).
The activation operation detection unit 401 repeats the operations from step S502 to step S508 in FIG. 5 until the battery 317 is exhausted.

[Check throwing action]
FIG. 6 is a graph showing a change in the total acceleration absolute value obtained from the starting acceleration sensor 312 when a measurement program is written in the pitching motion measuring device 101 and the pitching motion measuring device 101 is actually thrown up right above. It is. The horizontal axis is time, and the vertical axis is the combined acceleration absolute value.
In the stationary state, the combined acceleration absolute value obtained from the starting acceleration sensor 312 of the pitching motion measuring apparatus 101 is 1.0 G, which is the gravitational acceleration of the earth.
At time T601, the pitching movement measuring device 101 is thrown up right above. From the time T601 to the time T602, the combined acceleration absolute value increases from 1.0 G until the pitching movement measuring device 101 leaves the tester's hand at time T602.

  At time T602, the pitching motion measuring device 101 leaves the tester's hand, and therefore the acceleration applied to the pitching motion measuring device 101 tends to decrease. The speed of the pitching movement measuring device 101 that rises decreases. Eventually, the combined acceleration absolute value obtained from the starting acceleration sensor 312 of the pitching motion measuring apparatus 101 decreases to 1.0 G again. This time point T603 is a time point when the pitching motion measuring apparatus 101 reaches the apex where the pitching motion measuring apparatus 101 is thrown up and stops for a moment. Then, the pitching movement measuring device 101 starts to drop immediately. Then, at time T604, the combined acceleration absolute value decreases to a value close to 0G. That is, the state is almost close to zero gravity.

The activation operation detection unit 401 captures a weightless state that occurs after time T604, which is caused by the operation of throwing it right above. Therefore, the comparator 403 is used to detect that the total acceleration absolute value is less than the free fall detection threshold G605. Strictly speaking, at the time T606, the counter 310 starts counting the clock pulses output by the sample clock 405 from the time when the total acceleration absolute value becomes less than the free fall detection threshold G605. Then, at time T607 when the count value of the counter 310 reaches a predetermined value, the counter 310 outputs logic true.
As described above, the pitching motion measuring device 101 is thrown up right when the counter 310 detects that the pitching motion measuring device 101 maintains the free fall state for a predetermined time interval (between time points T606 and T607). It becomes possible to detect this.

In this embodiment, the pitching movement measuring device 101 is disclosed.
The pitching motion measuring device 101 in the form of a hard baseball detects a free fall state caused by throwing up the pitching motion measuring device 101 using the functions of the acceleration sensor 312 for activation, the comparator 403, and the counter 310. Thus, the power save mode can be shifted to the normal operation mode. That is, it is possible to easily shift to the power-on state without using a special device or the like.
Moreover, it is possible to manufacture the pitching movement measuring device 101 according to the embodiment of the present invention with the conventional hard baseball ball manufacturing equipment without using a special manufacturing process.

  The pitching movement measuring device 101 described in the present embodiment can be applied to a golf ball by further downsizing the core portion 204. In the case of a golf ball, it is shot measurement, not pitching movement measurement. That is, the present invention can be widely applied as a sensor device having a sensor enclosed in the center portion of a ball regardless of the type of game.

  The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and other modifications and application examples are provided without departing from the gist of the present invention described in the claims. including.

  DESCRIPTION OF SYMBOLS 101 ... Throwing motion measuring apparatus, 102 ... Pitcher, 201 ... Outer skin, 202 ... Cotton yarn layer, 203 ... Yarn layer, 204 ... Core part, 205 ... Printed circuit board, 301 ... One-chip microcomputer, 302 ... Bus, 303 ... CPU, 304 ... ROM, 305 ... RAM, 306 ... Non-volatile storage, 307 ... Near field communication unit, 308 ... Serial interface, 309 ... System clock, 310 ... Counter, 311 ... Driver, 312 ... Startup acceleration sensor, 313 ... 6 axes Sensors, 314 ... Geomagnetic sensors, 315 ... MOSFETs, 317 ... batteries, 401 ... start-up operation detection unit, 402 ... absolute value summation unit, 403 ... comparator, 404 ... free fall detection threshold, 405 ... sample clock, 406 ... command issue unit 407: Power control unit

Claims (3)

An electronic switch that controls the supply of power to the load;
An activation acceleration sensor that detects acceleration of three axes and sends acceleration data;
An absolute value summing unit that converts the X-axis acceleration data, Y-axis acceleration data, and Z-axis acceleration data obtained from the start-up acceleration sensor into absolute values, adds them together, and outputs a combined acceleration absolute value When,
A comparator that compares the combined acceleration absolute value with a free fall detection threshold that is below the gravitational acceleration of the earth;
The comparator includes a power supply control unit that turns on the electronic switch in response to detecting that the total acceleration absolute value is less than the free fall detection threshold for a predetermined time interval or more. A sensor device. In addition,
A system clock for supplying an operation clock to the arithmetic unit;
A short-range wireless communication unit for performing wireless communication with an external device;
The power control unit further includes
Controlling the frequency of the operation clock with respect to the system clock and the supply of power to the short-range wireless communication unit;
The sensor device according to claim 1. The load includes a six-axis sensor and a geomagnetic sensor.
The sensor device according to claim 1 or 2.

Images