JPH03251276A - Golf swing analyzing device - Google Patents

Abstract

PURPOSE:To more exactly grasp the state of a golf swing by measuring a load distribution applied to the soles of both feet, and detecting a moving state of the centroid from the obtained load distribution of the sole. CONSTITUTION:In a load distribution sensor 12, when pressure is applied to each piezoelectric element 16 from the upper part, a piezoelectric effect is generated in the piezoelectric element 16 corresponding to its pressure, and by switching successively control lines C1, C2, to Cm, pressure in each piezoelectric sensor 14 can be detected. Accordingly, a distribution of a load applied to the sole of a golfer which comes into contact on the piezoelectric sensors 14 placed like a matrix can be known. When the distribution of the load applied to the soles of both feet is measured, a personal computer 100 operates as a centroid detecting means, and from its distribution state of the load, the centroid of the body is derived. The centroid of the body can be desired simply by a calculation from the load distribution of both feet, and from a timewise motion of the load distribution, a moving state of the centroid of the body can be grasped.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a golf swing analysis device, and more particularly to a golf swing analysis device for analyzing the state of a golf swing from the load applied to both feet.

(Prior Art) FIG. 8 is an illustrative diagram showing an example of a conventional golf swing analysis device. This golf swing analysis device 1 includes a metal plate 2, and load cells 3 are installed at four ends of the lower surface of the metal plate 2, for example.

A golfer rides on the metal plate 2 and performs a golf swing. At this time, the loads applied to the four load meters 3 are different, and the center of gravity of the body is detected from the difference in these loads. Furthermore, the loads applied to the four load meters 3 change over time due to the golf swing, and by detecting changes in the loads, the state of movement of the center of gravity of the body is detected.

The golf swing can be analyzed based on the state of movement of the body's center of gravity, which can be used to correct the golf swing.

(Problems to be Solved by the Invention) However, simply knowing the state of movement of the center of gravity of the body is not sufficient to accurately grasp the state of the golf swing.

Therefore, a main object of the present invention is to provide a golf swing analysis device that can more accurately grasp the state of a golf swing.

(Means for Solving the Problems) This invention provides a load distribution measuring means for measuring the load distribution applied to the soles of both feet, and a shift state of the center of gravity based on the load distribution of the soles obtained by the load distribution measuring means. This is a golf swing analysis device including a center of gravity detection means for detecting.

(Function) The load distribution measuring means measures the distribution of the load applied to the sole of the foot, and the center of gravity detecting means measures the movement of the center of gravity of the body. Furthermore, since the state of movement of the body's center of gravity is determined from the distribution of the load applied to the sole of the foot, the relationship between the load distribution of the sole of the foot and the state of movement of the center of gravity can be seen in chronological order.

(Effects of the Invention) According to the present invention, since the relationship between the load distribution state applied to the sole of the foot and the movement state of the body's center of gravity can be understood in a time-series manner, compared to the case of using a conventional golf swing analysis device, It is possible to grasp the state of the golf swing more accurately. Therefore, if this golf swing analysis device is used, it can be effectively used to correct the golf swing.

The above objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

(Embodiment) FIG. 1 is an illustrative diagram showing an embodiment of the present invention. The golf swing analysis device 10 includes a load distribution sensor 12 that constitutes a part of load distribution measuring means.

This load distribution sensor 12 is for measuring the state of load distribution applied to the sole of the foot when a golfer rides on it.

The load distribution sensor 12 includes piezoelectric sensors 14 arranged in a matrix, as shown in FIG.

Each piezoelectric sensor 14 includes a piezoelectric element 16, a field effect transistor 1B, and a capacitor 20, and control lines C, . cz,...
C1 is arranged, and reading WR,, R1 is arranged in each column direction.
,...R,, are arranged. Furthermore, in each column direction, there are two wires 24 and 26 connected to the ground 22.
is installed.

FIG. 3 is an equivalent circuit diagram of one piezoelectric sensor 14.

The gate electrode of field effect transistor 18 is connected to control line C. Also, one of the source or drain electrodes of transistor 18 is connected to read vAR. The other of the source or drain electrodes is connected to an electrode 28 formed on the lower end surface of the piezoelectric element 16. An electrode 30 formed on the upper end surface of the piezoelectric element I6 is connected to a wiring 26 continuous to the ground 22. Further, a capacitor 20 is connected between an electrode 28 on the lower end surface of the piezoelectric element 16 and a wiring 24 continuous to the ground 22. That is, this capacitor 20 is connected in parallel to the piezoelectric element 16. Note that as the piezoelectric element 16, an element made of a highly rigid piezoelectric material such as piezoelectric ceramics or piezoelectric single crystal is used.

For example, as shown in FIG. 4, the piezoelectric sensors 14 arranged in a matrix form a controller 50 including a reading means.
connected to.

Control lines C, C2, . . . C1 of the piezoelectric sensor 14 are connected to a gate drive circuit 52. Furthermore, the gate drive circuit 52 is connected to a decoder circuit 54 for selecting one of the control fII lines of the piezoelectric sensor 14. Further, the reading lines R, , R, . . . R1 are connected to an integrating circuit 56 . This integrating circuit 56 has a plurality of read lines R+
, R2, . . . R, is connected to a multiplexer 58 for selecting signals from.

The output of multiplexer 58 is input to A/D converter 60 where it is converted into a digital signal and then stored in memory 64 via data bus 62. memory 6
4 is sent to a personal computer 100 as a calculation means via a data bus 62 and a data bus interface 66.

The controller 50 also includes a program controller 68 for controlling switching of the piezoelectric sensor 14, processing of read signals, and the like. Program controller 68
information is transferred to memory 6 via address/data bus 70.
4 can be conveyed. Further, the address/data bus 70 is
It is connected to personal computer 100 via address/data bus interface 72 .

Further, the controller 50 includes a control signal interface 74, and exchanges control signals with the personal computer 100 through this control signal interface 74.

Data bus interface 66, address/data bus interface 72, and control signal interface 74 are connected to an I10 interface 102 attached to personal computer 100. This I10 interface 102 allows the controller 5
0 and a personal computer 100 are connected. Furthermore, the personal computer 100 includes a CRTIO
4. Keyboard 106. Printer 108. A video printer 110, a floppy disk device ff1112, and the like are connected.

Next, the operation of the piezoelectric sensor 14 connected to the controller 50 will be explained.

The decoder circuit 54 first connects the transistor 1 to the control line C through the gate drive circuit 52.
8 becomes conductive. At this time, other control lines Cz,
C2, . . . C1 are in a non-conductive state. As a result, the information on the piezoelectric elements 16 in the row corresponding to the control line CI becomes readable through the read lines R1r, R2+, . . . , R7.

In this state, the piezoelectric sensor 14 connected to the reading line R is connected to the integrating circuit 56, and the corresponding piezoelectric element 16
The charges accumulated by applying pressure are discharged to the integrating circuit 56 side. At this time, the remaining reading lines R1, Rs,...
Since R7 is in an open circuit state, the information in the corresponding piezoelectric element is retained.

The charge discharged into the integrating circuit 56 is converted into a voltage output proportional to the charge. These values are sequentially selected by multiplexer 58, converted into 12-bit data by A/D converter 60, and all stored in memory 64. By performing this procedure for all control lines C, C1, . . . C1, all data proportional to the pressure at a certain moment is stored in the memory 64.

That is, in the load distribution sensor 12 described above, when pressure is applied to each piezoelectric element 16 from above, a piezoelectric effect is produced in the piezoelectric element 16 corresponding to the pressure, and the control lines CI, Cz
, . . . By sequentially switching C1, the pressure in each piezoelectric sensor 14 can be detected. Therefore, it is possible to know the distribution of the load applied to the soles of the golfers' feet that are in contact with the piezoelectric sensors 14 arranged in a matrix.

Pressure detection by each piezoelectric sensor 14 is performed continuously. That is, when the pressure in all the piezoelectric sensors 14 is detected, the first piezoelectric sensor 14 is selected again to detect the pressure, and thereafter piezoelectric elements are sequentially selected as described above to detect the pressure. This operation is repeated until the measurement is completed.

Charges corresponding to pressure changes are accumulated in the capacitor 2o of the piezoelectric sensor 14. If the voltage corresponding to the charge read from the piezoelectric sensor 14, that is, the voltage at the output terminal of the A/D converter 60 is represented by ■, then P=kV holds true. Note that P is a proportionality constant for pressure.

Here, if the charged charge is continuously read from the piezoelectric sensor 14 for each time Δ, the piezoelectric sensor 14 will be
is reset, so a charge corresponding to the subsequent pressure change will be accumulated. Therefore, when t=Δt-n, for the pressure P (t) one hour after the measurement, ΣV (i) −I holds true for P (t) =. Note that V (i) is the i-th measured voltage.

As described above, pressure can be measured continuously by accumulating the measured voltage for each measurement.

As shown in FIG. 5, at the start of measurement, the load value F of each piezoelectric sensor 14 is reset to zero.

Subsequently, the output from the piezoelectric sensor 14, that is, the output voltage of the A/D converter 60 is read. If this reading is the first time, a voltage value corresponding to the pressure change from the time of reset is read, and if this is the second or subsequent reading, a voltage value corresponding to the pressure change from the previous reading time is read. is loaded.

Next, the load change amount ΔF is determined from the read voltage. For example, if the amount of charge increases, the pressure value increases, and conversely, if the amount of charge decreases, the pressure value decreases. That is, ΔF has a positive or negative sign. Next, the obtained ΔF
Compute cumulatively. In this way, each step from reading the electric charge of the piezoelectric sensor 14 to cumulative calculation is performed for a certain period of time Δ
By repeating every T, the current load value is obtained.

Further, when the distribution of the load applied to the soles of both feet is measured, the personal computer 100 acts as a center of gravity detection means, and the center of gravity of the body is determined from the distribution of the load.

The center of gravity of the body can be easily calculated from the load distribution of both feet, and the state of movement of the center of gravity of the body can be understood from the temporal movement of the load distribution.

These changes in load distribution and movement of the center of gravity are as follows:
It is displayed on the CRT 104 or the like.

Further, the golf swing analysis device 10 includes a swing detection device 130. The swing detection device 130 has a ball holder 132. Ball retainer 132 includes a rotatably formed arm 134 that is configured to return to a home position, such as by a spring. An impact detection sensor 136 serving as impact detection means is attached to the lower part of the arm 134. As the impact detection sensor 136, a reflective photoelectric sensor or the like is used, for example, and detects rotation of the arm 134 to detect impact of the golf club on the ball.

A backswing detection sensor 13B serving as backswing detection means is installed near the impact detection sensor 136. As the bank swing detection sensor 138, for example, a reflective photoelectric sensor is used, and it detects that the addressed golf club has moved and has entered a backswing. As these impact detection sensors 136 and backswing detection sensors 13B, other sensors such as ultrasonic sensors can be used in addition to photoelectric sensors.

A follow swing detection sensor 140 serving as follow swing detection means is installed in the direction in which the golf club is backswinged. Follow swing detection sensor 1
As 40, for example, a sensor including an ultrasonic transmitter and receiver is used. Therefore, it is possible to detect that the golf club has passed between the transmitter and the receiver, thereby detecting that the golf club has moved from a backswing to a follow swing.

Further, after the golf club impacts the ball, the golf club moves to follow-through, and a follow-through detection sensor 142 as follow-through detection means is installed near the end of follow-through. As the follow-through detection sensor 142, for example, an ultrasonic sensor like the bank swing detection sensor 138 is used. Then, it is detected that the golf club has passed between the transmitter and the receiver of the follow-through detection sensor 142, and it is detected that the follow-through has ended. Note that as the follow-swing detection sensor 140 and the follow-through detection sensor 142, other sensors other than the ultrasonic type can be used, such as an optical type sensor.

These sensors are connected to the personal computer 100, and the golf swing is grasped in chronological order.

FIG. 6 and FIG. 7 show the results of analyzing the golf swings of two golfers. In these drawings, the load distribution applied to the sole of the foot is shown by equal pressure lines, and the greater the number of equal pressure lines, the greater the load on that part. Furthermore, we showed the movement of the center of gravity determined from the load distribution. The movement status of the center of gravity was expressed by indicating the position of the center of gravity as a dot every 0.025 seconds and connecting these points. In addition, in Figures 6 and 7, the moment of impact is set to 0 seconds,
The value before the impact is shown as a minus, and the value after the impact is shown as a plus.

The golfer shown in FIG. 6 and the golfer shown in FIG.
It can be seen that the direction in which the center of gravity moves is opposite. In other words,
The center of gravity of the golfer shown in FIG. 6 is moving counterclockwise, whereas the center of gravity of the golfer shown in FIG. 7 is moving clockwise.

Furthermore, this golf swing analysis device 10 can measure how the load is distributed on the soles of both feet. That is, in the golfer shown in FIG. 6, the weight largely shifts to the heel of the right foot during the backswing, and shifts largely to the outside of the left foot during the follow swing.

On the other hand, the golfer shown in Figure 7 enters the backswing with his weight near the big toes of both feet, shifts his weight evenly to his left foot at the moment of impact, and then shifts his weight back to the big toes of his left foot during the follow-through. Move. As a result, the athlete's body will be deflected backwards at the time of impact, resulting in more of the so-called ``top''. Incidentally, the golfer shown in FIG. 6 has a handicap of 10, and the golfer shown in FIG. 7 is a beginner.

Furthermore, by installing the swing detection device 130, the relationship between the actual golf swing, the change in the load distribution on the sole of the foot, and the movement of the center of gravity becomes clearer. That is, when the golfer addresses the golf club, the bank swing detection sensor 138 detects the golf club. Next, when the golfer starts a bank swing, it is detected that the golf club is missing from in front of the backswing detection sensor 138, and it is detected that the golfer has entered a bank swing.

When the backswing reaches the upper limit, the follow swing detection sensor 140 detects that the golf club has reached the upper limit and has shifted to the follow swing. When the golf club impacts the ball, the arm 134 of the ball holder 132 moves, and the impact detection sensor 136 detects this, thereby detecting that the golf club has impacted the ball.

Further, when the golf club reaches near the upper limit due to the follow-through, the follow-through detection sensor 142 detects that the follow-through has ended. In this way, the swing detection device 130 grasps the swing motion in chronological order.

Therefore, by superimposing the load distribution of the sole of the swing motion and the movement status of the center of gravity, the state of the golf swing can be accurately grasped in chronological order, which can be used to correct the golf swing.

[Brief explanation of drawings]

FIG. 1 is an illustrative view showing an embodiment of the present invention. FIG. 2 is an illustrative view showing a load distribution sensor used in the golf swing analysis device shown in FIG. 1. FIG. 3 is an equivalent circuit diagram of a piezoelectric sensor used in the load distribution sensor shown in FIG. 2. FIG. 4 is a block diagram of the golf swing analysis device shown in FIG. 1. FIG. 5 is a flow diagram when measuring load distribution. 6 and 7 are measurement result diagrams showing the results of golf swing analysis using the golf swing analysis device shown in FIG. 1. FIG. 8 is an illustrative view showing an example of a conventional golf swing analysis device that is the background of the present invention. In the figure, 10 is a golf swing analysis device, 12 is a load distribution sensor, 50 is a controller, 52 is a gate drive circuit, 54 is a decoder circuit, 56 is an integration circuit, 58
60 is a multiplexer, 60 is an A/D converter, 64 is a memory, 68 is a program controller, 100 is a personal computer, 130 is a swing detection device, 132
is a ball holder, 136 is an impact detection sensor, 13
Reference numeral 8 indicates a backswing detection sensor, 140 indicates a follow-swing detection sensor, and 142 indicates a follow-through detection sensor. Figure 5 Figure 1 00 gauze - 0.75 seconds 10. 50 seconds 1025 bamboo tshi + 0 25 trunk 0 ON Figure 7 - 1,00 cavities 10 5 ft 50 oak 1025 0 seconds 0 25# now 0 50 seconds Figure

Claims (1)

[Scope of Claims] 1. A load distribution measuring means for measuring the load distribution applied to the soles of both feet, and a means for detecting the movement state of the center of gravity from the load distribution on the soles obtained by the load distribution measuring means. A golf swing analysis device including a center of gravity detection means. 2. The load distribution measuring means includes a plurality of piezoelectric sensors arranged in a matrix and outputting voltage according to pressure changes, and a reading means for continuously reading voltage data from each of the plurality of piezoelectric sensors. 2. The golf swing analysis device according to claim 1, further comprising calculation means for cumulatively calculating the voltage data read by the reading means for each piezoelectric sensor. 3 Furthermore, a backswing detection means for detecting a transition from address to a backswing, a follow swing detection means for detecting a transition from a backswing to a follow swing, and a detection means for detecting that the golf club has made an impact on the ball. The golf swing analysis device according to claim 1 or 2, comprising an impact detection means for detecting the end of the follow-through after the impact, and a follow-through completion detection means for detecting the completion of the follow-through after the impact.