Golf club head fitting apparatus, fitting method, and fitting program

Abstract

To provide a golf club head fitting apparatus and the like capable of easily identifying indices relating to specifications of a golf club head suitable for a swing motion of each player.SOLUTION: A golf club head fitting apparatus 200 includes: an acquisition unit 201 that acquires measurement data obtained by measuring a swing motion of a golf club by a player by a measuring instrument; a calculation unit 202 that calculates a swing index on the basis of the measurement data; and a selection unit 203 that selects at least one club head index relating to specifications of a golf club head suitable for the player on the basis of the swing index.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a fitting device, a fitting method, and a fitting program for a golf club head.

Background Art

[0002] In recent years, various fitting devices have been proposed for measuring a player's swing motion and proposing a golf club shaft suitable for the player's swing motion (see Patent Documents 1 and 2 below).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] Golf club manufacturers are selling various golf club heads with different specifications in order to fit various players with different physiques and skills. Here, examples of the specifications of the golf club head include parameters related to head volume, moment of inertia, and center of gravity position.

[0005] However, since each player's swing motion is different, it is not easy to fit a golf club head suitable for each swing motion. In addition, if an index regarding the specifications of a golf club head suitable for a player's swing motion can be provided to the player, the player will have a wider range of options for selecting a golf club head to use, which is convenient.

[0006] The present invention has been devised in view of the above problems, and a main object thereof is to provide a golf club head fitting device, a fitting method, and a fitting program that can easily identify an index related to specifications of a golf club head suitable for each swing motion of a player.

Means for Solving the Problems

[0007] The present invention is a golf club head fitting device, including: an acquisition unit that acquires measurement data obtained by measuring a swing motion of a golf club by a player with a measuring instrument; a calculation unit that calculates a swing index based on the measurement data; and a selection unit that selects at least one club head index related to specifications of a golf club head suitable for the player based on the swing index.

Effects of the Invention

[0008] By adopting the above configuration, the golf club head fitting device of the present invention can easily identify at least one club head index related to specifications of a golf club head suitable for each swing motion of a player.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

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Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Best Mode for Carrying Out the Invention

[0010] Hereinafter, an embodiment of the present invention will be described based on the drawings. The following embodiments and the specific configurations shown in the drawings are for understanding the content of the present invention, and the present invention is not limited to the specific configurations shown. Also, for a plurality of embodiments, throughout the specification, the same or common elements are denoted by the same reference numerals, and duplicate explanations are omitted.

[0011] FIG. 1 shows an overall configuration diagram of a fitting system 1 including a fitting device 200 for a golf club head according to the present embodiment. Further, FIG. 2 shows a block configuration diagram of the fitting system 1 according to the present embodiment. In the present embodiment, for the fitting of a golf club head, first, the swing motion of a player 3 who wishes to fit a golf club head is measured. Next, swing indices are calculated from the swing motion. Then, based on this swing index, at least one club head index regarding the specifications of a golf club head suitable for the player 3 is selected. Therefore, the fitting system 1 of the present invention can easily identify at least one club head index regarding the specifications of a golf club head suitable for the individual swing motion of a player.

[0012] As shown in FIGS. 1 and 2, the fitting system 1 according to the present embodiment includes, for example, a swing sensor 100 that can be attached to a golf club 2 as a measuring device for measuring the swing motion of the golf club 2, a fitting device 200, and a display unit 300.

[0013] [Golf Club] The golf club 2 has, for example, a grip 21, a shaft 22, and a golf club head 23. In the present embodiment, a wood-type golf club is shown as the golf club 2. In other embodiments, the golf club 2 may be an iron-type or a hybrid-type having an intermediate shape between a wood-type and an iron-type.

[0014] The golf club 2 in FIG. 1 is a test golf club for measuring a swinging motion. Regarding the specifications of the test golf club, there are no particular restrictions, but it is desirable to have a shaft 22 (weight, hardness, torque, kick point, etc.) suitable for the swinging motion of the player 3. For example, prior to this measurement, the hardness of the shaft suitable for the swinging motion of the player 3 is determined in advance by a fitting device such as the above-mentioned Patent Document 1 or 2. Then, it is desirable that the test golf club be prepared to include the determined shaft. Thereby, the original swinging motion of the player 3 can be measured more accurately.

[0015] [Swing Sensor] In the present embodiment, the swinging motion is measured by the above-described swing sensor 100. The swing sensor 100 is configured to be attachable to the golf club 2, for example, as shown in FIG. 1. The swing sensor 100 of the present embodiment is detachable from the grip 21 or the shaft 22 of the golf club 2. The swing sensor 100 is preferably configured to be small and lightweight so as not to interfere with the swinging motion of the player 3.

[0016] The swing sensor 100 of the present embodiment can measure a predetermined physical quantity from the golf club 2 during the swinging motion. The swing sensor 100 of the present embodiment includes an angular velocity measurement unit 101 (FIG. 2) and can measure the angular velocity of the golf club 2 during the swinging motion. As shown in FIG. 1, the swing sensor 100 of the present embodiment can measure the angular velocities ωx, ωy, and ωz around the respective axes of the local coordinate system xyz with the attachment position to the golf club 2 as the origin at a predetermined sampling period (for example, 1 millisecond). Here, the x-axis is the toe-heel direction of the golf club head 23, the y-axis is the direction of the target flight line of the hit ball (the normal direction of the face of the golf club head 23), and the z-axis is the axial direction of the shaft 22.

[0017] Therefore, when a player 3 who desires fitting performs a swing in which a ball 4 is struck one or more times with a test golf club 2 to which a swing sensor 100 is attached, measurement data (the angular velocities ωx, ωy, and ωz) can be measured by the swing sensor 100.

[0018] As shown in FIG. 2, the swing sensor 100 of the present embodiment further includes a communication unit 102 for providing the measured measurement data to a fitting device 200. The communication unit 102 preferably uses a wireless method so as not to interfere with the swing operation. In other embodiments, the communication unit 102 may be a wired method. Further, the swing sensor 100 may include a removable storage medium (not shown) instead of the communication unit 102 or together with the communication unit 102. In this case, the measurement data may be temporarily stored in the storage medium and then imported into the fitting device 200 via this storage medium.

[0019] [Fitting Device] The fitting device 200 of the present embodiment acquires the measurement data of the swing sensor 100 and executes a predetermined process. The fitting device 200 may be realized, for example, as various general-purpose computers, tablet computers, smartphones, or even dedicated terminals.

[0020] As shown in FIG. 2, the fitting device 200 includes an acquisition unit 201 that acquires measurement data from the swing sensor 100, a calculation unit 202 that calculates a swing index based on the measurement data, and a selection unit 203 that selects a first club head index and a second club head index related to the specifications of a golf club head suitable for the player 3 based on the swing index. The fitting device 200 of the present embodiment also further includes a hierarchical data unit 204 in which the swing indexes are hierarchically classified and the first club head index and the second club head index are assigned to each layer.

[0021] The fitting device 200 of this embodiment further includes an input unit 205, a storage unit 206, and a control unit 207. The input unit 205 is composed of, for example, a keyboard, a mouse, a virtual keyboard of a tablet, etc. The storage unit 206 includes a non-volatile storage unit such as a hard disk in which a fitting program and various master data are stored, and a volatile storage unit which is a working memory. The control unit 207 operates each of the above units according to the program, and is composed of, for example, a central processor (CPU).

[0022] [Acquisition unit] The acquisition unit 201 of the fitting device 200 is configured to be communicable with the communication unit 102 of the swing sensor 100 by, for example, a wireless method. Therefore, the measurement data measured by the swing sensor 100 is acquired by the acquisition unit 201 via the communication unit 102. The measurement data acquired by the acquisition unit 201 is stored in the storage unit 206.

[0023] [Calculation unit] The calculation unit 202 calculates a swing index based on the measurement data acquired by the acquisition unit 201. The swing index is a feature quantity that quantitatively characterizes a certain swing motion. The swing index can adopt various feature quantities without particular limitation as long as it is such a feature quantity. In this embodiment, as the swing index, for example, a first swing index which is an index related to the cocking motion of the swing motion, and / or a second swing index which is an index related to the rotation around the shaft axis of the swing motion are adopted.

[0024] [First swing index (index related to cocking motion)] FIG. 3 shows a part of the player's hand and the shaft 22 from the top to the impact during the swing motion. Generally, the player's swing goes through the processes of address, backswing, top, downswing, and impact. Address means the stationary state (see FIG. 1) just before the player 3 starts the swing. The backswing is the motion of lifting the golf club 2 from the address. Thereafter, the motion of swinging down the golf club 2 is called the downswing. The timing of switching from the backswing to the downswing is the top. In these series of swing motions, the cocking motion is the motion of bending the joints of the player's wrist and elbow. The cocking motion is one of the important motions for transmitting speed and power to the golf club head 23 and hitting the ball far. This embodiment focuses on this cocking motion as the first swing index for quantitatively specifying the swing motion. The cocking motion is mainly detected by the swing sensor 100 as a rotational motion around the y-axis of the golf club 2 in the local coordinate system.

[0025] FIG. 4 shows, as measurement data, the relationship between the angular velocity in the cocking direction (i.e., the angular velocity ωy around the y-axis) and time in a player's swing motion. Time 0 indicates the moment when the ball is impacted. In this embodiment, the first swing index is obtained as a value obtained by integrating the angular velocity ωy in the cocking direction within a certain range over time. The first swing index of this embodiment is obtained, for example, as the integral value of the range (the hatched part in FIG. 4) from the top position (top) of the swing motion to the state where the cocking is released, i.e., the maximum position P1 of the angular velocity ωy. This integration range can be arbitrarily changed. The first swing index can specify the angular change in the cocking direction during the player's swing motion.

[0026] [Second Swing Index (Index Regarding Rotation)] The second swing index is an index related to the rotation around the shaft axis of the swing motion. Generally, the rotation around the shaft axis in the swing motion is called rotation. Rotation is mainly an operation accompanying the rotational motion of the player's body, and it plays a role in imparting speed and power to the golf club head 23 and enhancing the accuracy of the shot. In the present embodiment, attention is paid to this rotation as the second swing index for quantitatively specifying the swing motion. Rotation is mainly detected by the swing sensor 100 as the rotational motion around the z-axis of the golf club 2 in the local coordinate system.

[0027] FIG. 5 shows, as measurement data, the relationship between the angular velocity around the shaft axis (i.e., the angular velocity ωz around the z-axis) and time in the swing motion of a certain player. Time 0 indicates the moment when the ball is impacted. In the present embodiment, the second swing index is obtained as a value obtained by integrating the angular velocity ωz around the shaft axis within a certain range with respect to time. The second swing index of the present embodiment is, for example, the integral value in the range from the top position to the impact in the swing motion (the hatched portion in FIG. 5). This integration range can be arbitrarily changed. The second swing index can identify the angular change of rotation during the player's swing motion.

[0028] [Selection section] The selection section 203 of the fitting device 200 can select at least one club head index regarding the specifications of the golf club head suitable for the player 3 based on the above-described swing indices (the first swing index and / or the second swing index).

[0029] In this specification, examples of the specifications of the golf club head include head weight, head volume, lie angle, parameters related to the center of gravity position (e.g., center of gravity distance), moment of inertia, and the like.

[0030] The center of gravity position of the golf club head, for example, in the front view of the golf club head 23 placed in the reference state on the horizontal plane HP as shown in FIG. 6, is the toe-heel direction distance of the straight line drawn perpendicularly from the head center of gravity G toward the shaft axis CL (hereinafter, the center of gravity distance LB), and as shown in FIG. 7, in the side view of the golf club head 23 placed in the reference state on the horizontal plane HP, the face-back direction distance from the shaft axis CL to the head center of gravity G (hereinafter, the center of gravity distance LC), etc. are included.

[0031] As the moment of inertia of the golf club head, for example, the moment of inertia around the vertical axis passing through the head center of gravity in the reference state where the golf club head is placed on the horizontal plane with the specified lie angle and loft angle (hereinafter, the left-right MOI), the moment of inertia around the horizontal axis in the toe-heel direction passing through the head center of gravity (hereinafter, the up-down MOI), and at least one, preferably all, of the moment of inertia around the shaft axis (hereinafter, the around-axis MOI) are included.

[0032] In this specification, as the club head index, a variable obtained by combining a plurality of the above specifications with weights is used. In a preferred embodiment, the club head index includes a first club head index that is the first principal component obtained by performing principal component analysis on the specifications of a plurality of golf club heads. The first principal component is represented by a linear combination of the plurality of the above specifications (variables), and is determined so as to bring about the largest variation in the combination coefficients. Further, in a more preferred embodiment, the club head index further includes a second club head index that is the second principal component obtained by performing principal component analysis on the specifications of a plurality of golf club heads. The second principal component is determined in a direction orthogonal to the first principal component and so as to bring about the second largest variation. By using these first club head index and second club head index, a club head index considering a plurality of specifications of a golf club head can be provided. Further, if the first club head index and the second club head index suitable for the swing motion of player 3 are specified, one or a plurality of specific golf club heads satisfying the above indices can be easily specified from among various golf club heads being sold. That is, the first club head index and the second club head index are used as indices for narrowing down a specific golf club head from among various golf club heads.

[0033] [Stratified data section] In the fitting device 200 of the present embodiment, the selection unit 203 selects a first club head index and a second club head index suitable for player 3 based on the swing index of player 3 and the stratified data section 204. FIG. 8 visually shows an example of such a stratified data section 204. The stratified data section 204 is data prepared in advance, in which the swing indices are stratified into a plurality (classified into four layers K1 to K4 in this example), and a first club head index and a second club head index are assigned to each layer. Therefore, the selection unit 203 can easily select a first club head index and a second club head index suitable for the swing index by fitting the swing index of the player to be fitted to any layer of the stratified data section 204.

[0034] The stratified data section 204 of this embodiment is generated by associating, for example, a swing index stratified data section 204A as shown in FIG. 9 and a head feature map data section 204B as shown in FIG. 11. Each data section will be described below.

[0035] [Swing Index Stratified Data Section] As shown in FIG. 9, the swing index stratified data section 204A is data that generally associates the swing motions (swing indices) of a plurality of players with specific golf club heads suitable for each swing motion. The swing index stratified data section 204A can be created, for example, by the procedure shown in FIG. 10. That is, in this embodiment, the swing index stratified data section includes a step S1 of measuring the swing motions of a plurality of players, a step S2 of calculating respective swing indices from the swing motions of the plurality of players, a step S3 of performing a hitting test using a plurality of golf club heads by the plurality of players, a step S4 of evaluating the quality of the hit balls in the hitting test (for example, the flight distance, height, and / or the quality of left - right deviation), a step S5 of determining a golf club head suitable for each of the plurality of players based on the results of the evaluation, and a step S6 of stratifying the swing indices based on the results of step S5 and assigning at least one golf club head suitable for each layer.

[0036] In step S5, as shown in Table 1, for each player, one optimal golf club head is determined. In this example, any one of three golf club heads A to C with different specifications prepared in advance is determined as the one optimal golf club head.

[0037]

Table 1

[0038] FIG. 9 is a graph showing a visualization of the relationship between a first swing index, a second swing index, and a golf club head suitable for a swing motion as an example of the swing index stratified data section 204A. In FIG. 9, the value of the first swing index of the swing motion is set on the horizontal axis, and the value of the second swing index of the swing motion is set on the vertical axis. Also, in FIG. 9, swing motions specified by the first swing index and the second swing index of 29 players are plotted as representative ones. Also, there are three types of plot identification marks, each having the following meaning. White circle: The swing motion for which golf club head A was most suitable Black circle: The swing motion for which golf club head B was most suitable Square: The swing motion for which golf club head C was most suitable

[0039] Also, in the present embodiment, the specifications of golf club heads A to C are as shown in the following table.

[0040]

Table 2

[0041] Features of golf club head A: Golf club head A has a relatively large head volume among the pre-prepared golf club heads. Also, golf club head A has a relatively large moment of inertia (left-right MOI, up-down MOI, and around-axis MOI) among golf club heads A to C, and in particular, the left-right MOI is 5000 g·cm 2 as described above. Furthermore, golf club head A has the largest center of gravity distances LB and LC among golf club heads A to C. Such a golf club head A has a sense of security when addressing the ball, and has a high "forgiveness" because the movement (left-right wobbling) of the head at the time of a mishit is restricted.

[0042] Features of golf club head B: Among the golf club heads A to C, the golf club head B has a relatively small head volume. Also, the golf club head B has its moment of inertia (lateral MOI, vertical MOI, and MOI around the axis) positioned between that of the golf club head A and the golf club head C. Further, the golf club head B has the smallest center of gravity distance LB among the candidate golf club heads. Therefore, the golf club head B is excellent in terms of operability, such as being easy to adjust the orientation of the golf club head around the shaft axis during the swing operation.

[0043] Features of the golf club head C: The golf club head C also has a relatively large head volume among the golf club heads A to C. Also, the golf club head C has the smallest moment of inertia (lateral MOI, vertical MOI, and MOI around the axis) among the golf club heads A to C. Further, the golf club head C has the smallest center of gravity distance LC among the golf club heads A to C. Such a golf club head C has a low center of gravity height on the face (also referred to as the sweet spot height), and tends to reduce the amount of backspin of the hit ball. Also, due to the small MOI around the axis, the operability is also good.

[0044] In FIG. 9, further, based on the plotted data, the swing indices are stratified into six levels L1 to L6. And for each of the levels L1 to L6, one or two of the golf club heads A to C suitable for the respective swing operations are assigned. In the example of FIG. 9, for each of the levels L1 to L6, the following recommended golf club heads are assigned from the golf club heads A to C, respectively. Level L1: Golf club head B Level L2: Golf club heads B, C Level L3: Golf club head C Level L4: Golf club heads A, B Level L5: Golf club heads A, C Level L6: Golf club head A

[0045] Layer L1 is a group of swing motions where both the first swing index and the second swing index are relatively large. In other words, the swing motions belonging to layer L1 have a large cocking motion and rotation, so the face opening and closing motion from the top to the impact is relatively large. In the embodiment of FIG. 9, based on the impact test, golf club head B is assigned as the optimal one for the swing motion of layer L1. As described above, since golf club head B has a small moment of inertia or a small center of gravity distance LB, it is presumed to be suitable for the swing motion of layer L1 with a large face opening and closing motion because it has relatively good operability.

[0046] In contrast to layer L1, layer L6 is a group of swing motions where both the first swing index and the second swing index are relatively small. In other words, the swing motions belonging to layer L6 have a small cocking motion and rotation, so the face opening and closing motion from the top to the impact is relatively small. In the embodiment of FIG. 9, based on the impact test, golf club head A is assigned as the optimal one for the swing motion of layer L6. As described above, since golf club head A has a large moment of inertia or a large center of gravity distance LC, it is presumed to be suitable for the swing motion of layer L6 with a small face opening and closing motion.

[0047] Layer L3 is a group of swing motions where the first swing index is relatively large and the second swing index is relatively small. In other words, the swing motions belonging to layer L3 are unbalanced swings with a large cocking motion but a small rotation. Therefore, it is necessary to assist the rotation. In the embodiment of FIG. 9, golf club head C is assigned as the optimal golf club head for layer L3. As described above, since golf club head C has a small center of gravity distance LC and the smallest moment of inertia, it is a head that is easy to rotate, so it is presumed to be suitable for the swing motion of layer L3.

[0048] In the swing index stratification data section 204A, layer L2 is a boundary layer located between layer L1 and layer L3. Even in the impact test, for the swing motions belonging to layer L2, the two golf club heads B and C suitable for layer L1 and layer L3 result in optimal outcomes, and these are assigned to them.

[0049] Also, in the swing index stratification data section 204A, layer L4 is a boundary layer located between layer L1 and layer L6. Even in the impact test, for the swing motions belonging to layer L4, the two golf club heads A and B suitable for layer L6 and layer L1 result in optimal outcomes, and these are assigned to them.

[0050] Furthermore, in the swing index stratification data section 204A, layer L5 is a boundary layer located between layer L3 and layer L6. Even in the impact test, for the swing motions belonging to layer L5, the two golf club heads A and C suitable for layer L6 and layer L3 result in optimal outcomes, and these are assigned to them.

[0051] [Head characteristic map data section] Next, based on FIG. 11, the head characteristic map data section will be described. As shown in FIG. 11, the head characteristic map data section 204B is generally data obtained by performing principal component analysis on the specifications of a plurality of golf club heads and organizing them into the first principal component and the second principal component. The plurality of golf club heads include at least the golf club heads A to C used in the generation of the previous swing index stratification data section 204A, in addition to a number of golf club heads sold by various golf club manufacturers. Also, since the specifications include the various items described above, in this embodiment, some of the specifications of the golf club heads are selected, principal component analysis is performed on them, and the items that change in the same way are organized. In this embodiment, principal component analysis was performed using eight items: head weight, head volume, lie angle, center of gravity distance LB, center of gravity distance LC, left - right MOI, up - down MOI, and around - axis MOI from the specifications of the plurality of golf club heads. Table 3 shows the principal component coefficients as the analysis results of the first principal component and the second principal component at that time.

[0052]

Table 3

[0053] As is clear from Table 3, when the eight specifications of various golf club heads are expanded into orthogonal modes by principal component analysis, it can be seen that the contribution of the moment of inertia (left - right MOI, up - down MOI, and MOI around the axis) and the center - of - gravity distance LC is large for the first principal component. Such a first principal component includes at least the left - right MOI, up - down MOI, MOI around the axis, and the center - of - gravity distance LC, and is a variable obtained by combining them with weights assigned respectively. Also, it can be seen that the contribution of the head weight, head volume, lie angle, and center - of - gravity distance LB is large for the second principal component. Such a second principal component is a variable obtained by combining at least the head weight, head volume, lie angle, and center - of - gravity distance LB with weights assigned respectively. By principal component analysis, for a number of golf club heads, the eight specifications can be reduced and classified into two variables.

[0054] Next, in the present embodiment, the head feature map data section 204B is generated by arranging a plurality of golf club heads for which principal component analysis has been performed on a two - dimensional map with the first principal component and the second principal component as coordinate axes respectively. In FIG. 11, the horizontal axis is the first principal component, with the left side being positive and the right side being negative. Also, the vertical axis is the second principal component, with the upper side being positive and the lower side being negative. Further, the previous golf club heads A, B, and C are also plotted in this head feature map data section 204B.

[0055] Here, in the head feature map data section 204B of FIG. 11, it can be seen that the distribution arrangements of the golf club heads A, B, and C are almost the same as the distribution arrangements of the layers L6, L1, and L3 in the swing index stratification data section 204A of FIG. 9. Therefore, the layers L1 to L6 obtained in FIG. 9 can be applied to the regions where the golf club heads A, B, and C are located in FIG. 11. Also, the first principal component which is the horizontal axis of the head feature map data section 204B in FIG. 11 can be made to correspond to the first swing index which is the horizontal axis of the swing index stratification data section 204A in FIG. 9, and the second principal component which is the vertical axis of the head feature map data section 204B can be made to correspond to the second swing index which is the vertical axis of the swing index stratification data section 204A. From the above, in the head feature map data section 204B of FIG. 11, it can be estimated that the golf club heads plotted on the right side of the horizontal axis are suitable for swing motions with a large first swing index. Similarly, it can be estimated that the golf club heads plotted on the upper side of the vertical axis are suitable for swing motions with a large second swing index.

[0056] In this embodiment, based on the above considerations, the vertical axis and the horizontal axis of the head feature map data section 204B in FIG. 11 are replaced with the first swing index and the second swing index respectively so as to link with the results of the swing index stratification data section 204A in FIG. 9, thereby obtaining the stratified data section 204 in FIG. 8. Also, in the stratified data section 204, it is stratified into four layers K1 to K4 by two orthogonal dividing lines a and b, and for the swing motions of each of the layers K1 to K4, a first club head index and a second club head index suitable therefor are respectively assigned. In FIG. 8, the vertical dividing line a is set to pass through, for example, the middle of the golf club heads A and C, and the horizontal dividing line b is set to pass through the golf club head B.

[0057] In FIG. 8, the layers K1 and K2 are groups of swing motions where the first swing index is larger than a predetermined first threshold value X. It can be seen that for the swing motions belonging to these layers K1 and K2, golf club heads with a relatively small first club head index (first principal component) are suitable.

[0058] Layer K1 is a group of swing motions in which the first swing index is greater than a predetermined first threshold value X and the second swing index is greater than a predetermined second threshold value Y. It can be seen that for the swing motions belonging to this layer K1, a club head with a relatively small first club head index (first principal component) and a relatively large second club head index (second principal component) is suitable.

[0059] Focusing on the contribution rates of various elements in the first principal component and the second principal component, for the swing motions of layer K1, golf club heads with a small moment of inertia and a large head weight tend to be suitable. When analyzed in more detail, as the golf club head belonging to layer K1, the left - right MOI is desirably less than, for example, 4800 g·cm 2 Preferably, it is less than 4800 g·cm. Also, the up - down MOI is desirably less than, for example, 3200 g·cm 2 Preferably, it is less than 3200 g·cm. Further, the around - axis MOI is desirably less than, for example, 8600 g·cm 2 Preferably, it is less than 8600 g·cm. Specific numerical values of these specifications may also be stored in association with layer K1 of the layer - specific data section 204.

[0060] Layer K2 is a group of swing motions in which the first swing index is greater than a predetermined first threshold value X and the second swing index is less than a predetermined second threshold value Y. It can be seen that for the swing motions belonging to this layer K2, a club head with a relatively small first club head index (first principal component) and a relatively small second club head index (second principal component) is suitable.

[0061] Focusing on the contribution rates of various elements in the first principal component and the second principal component, for the swing motions of layer K2, golf club heads with a small moment of inertia and a small head weight tend to be suitable. As the golf club head belonging to layer K2, it is desirable that the left - right MOI, the up - down MOI, and the around - axis MOI are all in the same range as the golf club head belonging to layer K1. Specific numerical values of these specifications may also be stored in association with layer K2 of the layer - specific data section 204.

[0062] In FIG. 8, layers K3 and K4 are groups of swing operations with a swing motion where the first swing index is smaller than a predetermined first threshold value X. It can be seen that a golf club head with a relatively large first club head index (first principal component) is suitable for the swing operations belonging to these layers K3 and K4.

[0063] Layer K3 is a group of swing operations where the first swing index is smaller than a predetermined first threshold value X and the second swing index is larger than a predetermined second threshold value Y. It can be seen that a club head with a relatively large first club head index (first principal component) and a relatively large second club head index (second principal component) is suitable for the swing operations belonging to this layer K3.

[0064] Focusing on the contribution rates of the various elements in the first principal component and the second principal component, there is a tendency for swing operations of layer K3 to be suitable for a golf club head with a large moment of inertia and a large head weight. When analyzed in more detail, as a golf club head belonging to layer K3, the left - right MOI is, for example, 4800 g·cm 2 or more is desirable. Also, the up - down MOI is, for example, 3200 g·cm 2 or more is desirable. The specific numerical values of these various elements are also stored in association with layer K3 of the layer - specific data section 204.

[0065] Layer K4 is a group of swing operations where the first swing index is smaller than a predetermined first threshold value X and the second swing index is smaller than a predetermined second threshold value Y. It can be seen that a club head with a relatively large first club head index (first principal component) and a relatively small second club head index (second principal component) is suitable for the swing operations belonging to this layer K4.

[0066] Focusing on the contribution rates of various specifications in the first principal component and the second principal component, for the swing motion of layer K4, a golf club head with a large moment of inertia and a small head weight is likely to be suitable. As the golf club head belonging to layer K4, it is desirable that the left - right MOI, the up - down MOI, and the MOI around the axis are all in the same range as the golf club head belonging to layer K3. These numerical values are also stored in association with layer K4 in the layer - specific data section 204.

[0067] Table 4 shows the specifications of the representative models of the golf club heads belonging to each of the layers K1 - K4 in this embodiment.

Table 4

[0068] By referring to the layer - specific data section 204, the selection unit 203 determines which of the layers K1 - K4 the first swing index and the second swing index of the player to be fitted belong to, and can select (specify) the first club head index and / or the second club head index of the golf club head assigned to the corresponding layer.

[0069] The first club head index and the second club head index selected by the selection unit 203 are displayed on the display unit 300. Specifically, the value of the first principal component can be displayed as the first club head index, and the value of the second principal component can be displayed as the second club head index. The display unit 300 is configured as, for example, a display or a printer.

[0070] The user of the fitting device 200 can grasp the first club head index and / or the second club head index suitable for the swing motion of the object to be fitted through the display unit 300. Therefore, the user who has received the fitting can identify a golf club head having specifications close to the value of the first principal component from among various golf club heads. Also, with reference to the values of the first principal component and the second principal component, a golf club head having specifications close to them can be identified. The above-mentioned users include not only players but also all those who need the analysis results of golf swings, such as instructors and developers of golf equipment.

[0071] Furthermore, as a more specific fitting, pay attention to the moment of inertia (MOI) around the axis, the left-right MOI, the up-down MOI, and the center of gravity distance LC of the golf club head that contribute greatly among the first club head indices (the first principal component), and these specific ranges may be displayed in combination with the first club head index. Similarly, pay attention to the head weight, head volume, lie angle, and center of gravity distance LB that contribute greatly among the second club head indices (the second principal component), and these specific ranges may also be displayed in combination with the second club head index. Furthermore, in addition to the first club head index and the second club head index, one or more golf club heads corresponding to the layer to which the swing motion belongs (plotted in FIG. 8) may be selected and displayed.

[0072] FIG. 12 shows the results of a hitting test with a golf club using a golf club head that satisfies the first and second club head indices selected by the fitting device 200 of the present embodiment for a certain player (Example). On the other hand, FIG. 13 shows the results of a hitting test with a golf club using a golf club head that does not satisfy the selected first and second club head indices for the player (Comparative Example). For each, as the trajectory of the hit ball, the flight distance, height, and left-right deviation were measured. Note that the same shaft is employed for the golf clubs in both the example and the comparative example. As is clear from the comparison between FIGS. 12 and 13, it can be seen that in the comparative example, the variation in the flight distance and height of the hit ball is large. On the other hand, when hitting with a golf club head suitable for the swing motion, the flight distance and directionality of the hit ball are greatly improved, and the usefulness of the fitting of the present embodiment was confirmed.

[0073] [Other Embodiments: Shaft Fitting] In other embodiments, following the fitting of the golf club head, fitting of the shaft of the golf club (more specifically, the shaft length) can be performed. As a result of various experiments by the inventors, when the rotation (second swing index) is small, the torsional motion during the swing motion is small, the motion of opening and closing the face of the golf club head is small, but the motion of returning the golf club (the motion of swinging the golf club) tends to be large. Therefore, for such a swing motion, using a long shaft and making it difficult to return the golf club tends to improve the directionality of the hit ball and the like.

[0074] On the other hand, when the rotation (second swing index) is large, the torsional motion during the swing motion is large, the motion of opening and closing the face of the golf club head is large, but the motion of returning the golf club tends to be small. Therefore, for such a swing motion, using a short shaft and making it easy to return the golf club tends to improve the directionality of the hit ball and the like.

[0075] The fitting device 200 of the present embodiment can also perform fitting of a shaft suitable for the swing operation by paying attention to the magnitude of the second swing index related to rotation among the swing indexes measured during fitting of the golf club head according to the above-described judgment criteria. This process is mainly executed by the shaft length selection unit 208 (FIG. 2) of the fitting device 200.

[0076] FIG. 14 is a flowchart showing an example of the process of the shaft fitting method. As shown in FIG. 14, in this process, the shaft length selection unit 208 performs step S10 of comparing the already calculated second swing index with a predetermined first threshold value. When the second swing index is equal to or greater than the first threshold value (Y in step S10), the shaft length selection unit 208 proposes a short shaft (step S11). Specifically, the shaft length selection unit 208 causes the display unit 300 to display a list of the shaft length (in inches) or specific shaft product names that satisfy it.

[0077] Also, when N in step S10, step S12 of comparing the second swing index with a predetermined second threshold value (<first threshold value) is performed by the shaft length selection unit 208. When the second swing index is equal to or less than the second threshold value (Y in step S12), the shaft length selection unit 208 proposes a long shaft (step S13). Specifically, the shaft length selection unit 208 causes the display unit 300 to display a list of the shaft length (in inches) or specific shaft product names that satisfy it.

[0078] Furthermore, when N in step S12, the shaft length selection unit 208 proposes a shaft of a standard length (step S14). Specifically, the shaft length selection unit 208 causes the display unit 300 to display a list of the shaft length (in inches) or specific shaft product names that satisfy it.

[0079] As an example, a shaft of standard length is preferably greater than, for example, 44.75 inches and less than 45.25 inches. As a short shaft, for example, 44.75 inches or less is preferable. As a long shaft, for example, 45.25 inches or more is preferable.

[0080] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above specific disclosure, and various modifications can be made and implemented within the scope of the technical idea described in the claims.

[0081] [Appendix] The present invention includes the following aspects.

[0082] [Invention 1] A fitting device for a golf club head, comprising: an acquisition unit that acquires measurement data obtained by measuring the swing motion of a golf club by a player using a measuring device; a calculation unit that calculates a swing index based on the measurement data; a selection unit that selects at least one club head index related to the specifications of a golf club head suitable for the player based on the swing index; A fitting device for a golf club head including the above. [Invention 2] The fitting device for a golf club head according to Invention 1, wherein the swing index includes a first swing index that is an index related to the cocking motion of the swing motion and a second swing index that is an index related to the rotation around the shaft axis of the swing motion. [Invention 3] The fitting device for a golf club head according to Invention 2, further including a layer separation data part in which the swing index is layer-separated and at least one club head index is assigned to each layer, wherein the selection unit selects the club head index suitable for the player based on the swing index of the player and the layer separation data part. [Invention 4] The at least one club head index includes a first club head index that is the first principal component obtained by performing principal component analysis on the specifications of a plurality of golf club heads, and a second club head index that is the second principal component obtained by performing principal component analysis on the specifications of the plurality of golf club heads. The golf club head fitting device according to Invention 3 of the present invention. [Invention 5 of the present invention] The selection unit selects the relatively small first club head index when the first swing index is greater than a predetermined first threshold value. The golf club head fitting device according to Invention 4 of the present invention. [Invention 6 of the present invention] The selection unit selects the relatively large second club head index when the second swing index is greater than a predetermined second threshold value. The golf club head fitting device according to Invention 4 or 5 of the present invention. [Invention 7 of the present invention] The selection unit selects the relatively small second club head index when the second swing index is smaller than a predetermined second threshold value. The golf club head fitting device according to any one of Claims 4 to 6 of the present invention. [Invention 8 of the present invention] (Layers K3 & K4 in FIG. 8) The selection unit selects the relatively large first club head index when the first swing index is smaller than a predetermined first threshold value. The golf club head fitting device according to any one of Claims 4 to 7 of the present invention. [Invention 9 of the present invention] The selection unit selects the relatively large second club head index when the second swing index is greater than a predetermined second threshold value. The golf club head fitting device according to any one of Claims 4 to 8 of the present invention. [Invention 10 of the present invention] The selection unit selects the relatively small second club head index when the second swing index is smaller than a predetermined second threshold value. The golf club head fitting device according to any one of Claims 4 to 9 of the present invention. [Invention 11 of the present invention] The fitting device for a golf club head according to the second aspect of the present invention, further comprising a shaft length selection unit that selects the length of the shaft based on the second swing index. [The twelfth aspect of the present invention] The fitting device for a golf club head according to any one of the fourth to eleventh aspects of the present invention, wherein the first principal component is a variable obtained by combining, with weights, at least the moment of inertia about the vertical axis passing through the head center of gravity, the moment of inertia about the horizontal axis in the toe-heel direction passing through the head center of gravity, the moment of inertia about the shaft axis, and the center of gravity distance LC which is the distance in the face-back direction from the shaft axis to the head center of gravity, as the specifications. [The thirteenth aspect of the present invention] The fitting device for a golf club head according to any one of the fourth to eleventh aspects of the present invention, wherein the second principal component is a variable obtained by combining, with weights, at least the head weight, the head volume, the lie angle, and the center of gravity distance LB which is the distance in the toe-heel direction of the straight line drawn perpendicularly from the head center of gravity to the shaft axis, as the specifications. [The fourteenth aspect of the present invention] The layer data unit is generated by associating a swing index stratification data unit that stratifies the swing index and assigns an optimal golf club head to each layer, and a head feature map data unit that classifies a plurality of golf club heads including the optimal golf club head by the first principal component and the second principal component. The fitting device for a golf club head according to any one of the fourth to twelfth aspects of the present invention. The fitting device for a golf club head according to any one of the fourth to twelfth aspects of the present invention, wherein the layer data unit [The fifteenth aspect of the present invention] A fitting method for a golf club head, comprising: a step of acquiring measurement data obtained by measuring a swing operation of a golf club by a player with a measuring device; a step of calculating a swing index based on the measurement data; a step of stratifying a plurality of golf club heads based on a plurality of specifications with at least one club head index, and creating a layer data unit in which the swing index is assigned to each layer; Selecting the club head index of the golf club head suitable for the player based on the swing index and the stratified data section; A fitting method for a golf club head including . [Invention 16] A golf club head fitting program, comprising: Obtaining measurement data obtained by measuring the swing motion of a golf club by a player using a measuring device; Calculating a swing index based on the measurement data; Stratifying at least one club head index based on a plurality of specifications for a plurality of golf club heads, and creating a stratified data section in which the swing index is assigned to each layer; Selecting the club head index of the golf club head suitable for the player based on the swing index and the stratified data section; A golf club head fitting program for causing a computer to execute. [Invention 17] A golf club head fitting system including a measuring device for measuring the swing motion of a golf club by a player and the fitting device according to any one of Claims 1 to 14 of the present invention.

Explanation of Signs

[0083] 1 Fitting system 2 Golf club 3 Player 23 Golf club head 24 Stratified data section 200 Fitting device 201 Acquisition unit 202 Calculation unit 203 Selection unit 204 Stratified data section 204A Swing index stratified data section 204B Head feature map data section

Claims

Claim 1 A fitting device for a golf club head, comprising: an acquisition unit that acquires measurement data obtained by measuring the swing motion of a golf club by a player using a measuring instrument; a calculation unit that calculates a swing index based on the measurement data; a selection unit that selects at least one club head index related to the specifications of a golf club head suitable for the player based on the swing index; A fitting device for a golf club head including the above. Claim 2 The fitting device for a golf club head according to claim 1, wherein the swing index includes a first swing index which is an index related to the cocking motion of the swing motion, and a second swing index which is an index related to the rotation around the shaft axis of the swing motion. Claim 3 The swing index is stratified, and the fitting device for a golf club head further includes a layer-specific data part in which at least one club head index is assigned to each layer, The selection unit selects the club head index suitable for the player based on the swing index of the player and the layer-specific data part. The fitting device for a golf club head according to claim 2. Claim 4 The at least one club head index includes a first club head index which is a first principal component obtained by performing principal component analysis on the specifications of a plurality of golf club heads, and a second club head index which is a second principal component obtained by performing principal component analysis on the specifications of the plurality of golf club heads. The fitting device for a golf club head according to claim 3. Claim 5 The selection unit selects the relatively small first club head index when the first swing index is greater than a predetermined first threshold value. The fitting device for a golf club head according to claim 4. Claim 6 The selection unit selects the relatively large second club head index when the second swing index is greater than a predetermined second threshold value. The fitting device for a golf club head according to claim 5. Claim 7 The selection unit selects the relatively small second club head index when the second swing index is smaller than a predetermined second threshold value. The fitting device for a golf club head according to claim 5. Claim 8 The fitting device for a golf club head according to claim 4, wherein the selection unit selects the relatively large first club head index when the first swing index is smaller than a predetermined first threshold value.

9. The fitting device for a golf club head according to claim 8, wherein the selection unit selects the relatively large second club head index when the second swing index is larger than a predetermined second threshold value.

10. The fitting device for a golf club head according to claim 8, wherein the selection unit selects the relatively small second club head index when the second swing index is smaller than a predetermined second threshold value.

11. The fitting device for a golf club head according to claim 2, further comprising a shaft length selection unit that selects the length of the shaft based on the second swing index.

12. The fitting device for a golf club head according to any one of claims 4 to 11, wherein the first principal component is a variable obtained by weighting and combining, as the specifications, at least the moment of inertia about the vertical axis passing through the head center of gravity, the moment of inertia about the horizontal axis in the toe - heel direction passing through the head center of gravity, the moment of inertia about the shaft axis, and the center - of - gravity distance LC which is the distance in the face - back direction from the shaft axis to the head center of gravity.

13. The fitting device for a golf club head according to any one of claims 4 to 11, wherein the second principal component is a variable obtained by weighting and combining, as the specifications, at least the head weight, the head volume, the lie angle, and the center - of - gravity distance LB which is the distance in the toe - heel direction of the straight line drawn perpendicularly from the head center of gravity to the shaft axis.

14. The layer - specific data unit is generated by associating a swing - index layer - specific data unit that classifies the swing index and assigns an optimal golf club head to each layer, and a head - feature map data unit that classifies a plurality of golf club heads including the optimal golf club head by the first principal component and the second principal component. The fitting device for a golf club head according to claim 4.

15. A fitting method for a golf club head, comprising: a step of acquiring measurement data obtained by measuring a swing operation of a golf club by a player with a measuring device; A step of calculating a swing index based on the measurement data; A step of stratifying a plurality of golf club heads based on a plurality of specifications with at least one club head index, and creating a stratified data section in which the swing index is assigned to each layer; A step of selecting the club head index of the golf club head suitable for the player based on the swing index and the stratified data section; A fitting method for a golf club head including the above.

16. A fitting program for a golf club head, A step of acquiring measurement data obtained by measuring the swing motion of a golf club by a player with a measuring device; A step of calculating a swing index based on the measurement data; A step of stratifying a plurality of golf club heads based on a plurality of specifications with at least one club head index, and creating a stratified data section in which the swing index is assigned to each layer; A step of selecting the club head index of the golf club head suitable for the player based on the swing index and the stratified data section; A fitting program for a golf club head that causes a computer to execute the above.

17. A fitting system for a golf club head, including a measuring device for measuring the swing motion of a golf club by a player and the fitting device according to any one of claims 1 to 11.

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