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

Abstract

[Problem] To provide a golf club head fitting device and the like that can easily specify an index related to a specification for a golf club head that is suited to the swing of each player.　[Solution] A golf club head fitting device 200 includes an acquisition unit 201 that acquires measurement data obtained as a result of a measurement apparatus measuring the swing of a golf club by a player, 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 related to a specification for a golf club head that is suited to the player on the basis of the swing index.

Description

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

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

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

[0003] JP 2023-103070 A Patent No. 6087132 A

[0004] Golf club manufacturers sell a variety of golf club heads with different specifications to suit players of different physiques and skill levels. Examples of the specifications of a golf club head include parameters related to the head volume, moment of inertia, and center of gravity.

[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. Furthermore, if it were possible to provide a player with guidelines regarding the specifications of a golf club head suitable for their swing motion, the player would have a wider range of options for the golf club head to use, which would be convenient.

[0006] The present invention was devised in consideration of the above-mentioned problems, and its main objective is to provide a golf club head fitting device, fitting method, and fitting program that can easily identify indicators related to the specifications of a golf club head that are suitable for each player's swing motion.

[0007] The present invention is a golf club head fitting device that includes an acquisition unit that acquires measurement data obtained by measuring a player's golf club swing motion using a measuring device, 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 a parameter of a golf club head that is suitable for the player based on the swing index.

[0008] By adopting the above-described configuration, the golf club head fitting device of the present invention makes it possible to easily identify at least one club head index relating to the specifications of a golf club head that is suitable for each player's swing motion.

[0009] 1 is a diagram illustrating an overall configuration of a golf club head fitting system according to an embodiment of the present invention; FIG. 2 is a block diagram of the fitting system according to an embodiment of the present invention; FIG. 3 is a diagram illustrating a swing motion; FIG. 4 is a graph illustrating the relationship between time in a swing motion and angular velocity in the cocking direction; FIG. 5 is a graph illustrating the relationship between time in a swing motion and angular velocity around the shaft axis; FIG. 6 is a front view of a golf club head placed in a reference state for explaining center of gravity distance LB; FIG. 7 is a side view of a golf club head placed in a reference state for explaining center of gravity distance LC, viewed from the toe side; FIG. 8 is a graph illustrating the relationship between a first swing index, a second swing index, a first club head index, and a second club head index, using the stratified data section as an example; FIG. 9 is a graph illustrating the relationship between a first swing index, a second swing index, and candidate golf club heads, using the swing index stratified data section as an example; 1 is a flowchart showing an example of a processing procedure for fitting a shaft length, showing the results of a hit by a player using a golf club head other than the golf club head selected by the fitting device as a comparative example, the results of the hit by a player using a golf club head other than the golf club head selected by the fitting device, showing the flight distance, lateral deviation, and height of the hit ball.

[0010] An embodiment of the present invention will be described below with reference to the drawings. The specific configurations shown in the following embodiments and drawings are intended to aid in understanding the contents of the present invention, and the present invention is not limited to the specific configurations shown. Furthermore, in multiple embodiments, the same or common elements are designated by the same reference numerals throughout the specification, and redundant explanations will be omitted.

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

[0012] As shown in Figures 1 and 2, the fitting system 1 of this embodiment includes, for example, a swing sensor 100 that can be attached to a golf club 2 as measuring equipment 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 this 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 club, a hybrid club having a shape intermediate between the wood-type and iron-type clubs, or the like.

[0014] The golf club 2 in FIG. 1 is a test golf club for measuring a swing motion. There are no particular restrictions on the specifications of the test golf club, but it is desirable that it has a shaft 22 (weight, hardness, torque, kick point, etc.) that is suitable for the swing motion of the player 3. For example, prior to the actual measurement, the shaft hardness, etc. that is suitable for the swing motion of the player 3 is determined in advance using a fitting device such as that described in Patent Document 1 or 2 above. Then, it is desirable that the test golf club is prepared so as to have the determined shaft. This allows the original swing motion of the player 3 to be measured more accurately.

[0015] [Swing Sensor] In this embodiment, the swing 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 this embodiment is detachable from the grip 21 or shaft 22 of the golf club 2. It is desirable that the swing sensor 100 be configured to be small and lightweight so as not to interfere with the swing motion of the player 3.

[0016] The swing sensor 100 of this embodiment can measure a predetermined physical quantity from the golf club 2 during a swing motion. The swing sensor 100 of this embodiment includes an angular velocity measurement unit 101 ( FIG. 2 ) and can measure the angular velocity of the golf club 2 during a swing motion. As shown in FIG. 1 , the swing sensor 100 of this embodiment can measure angular velocities ωx, ωy, and ωz about each axis of a local coordinate system x, y, and z, which has its origin at the attachment position to the golf club 2, at a predetermined sampling period (e.g., 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 to 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 wishing to be fitted swings the test golf club 2 equipped with the swing sensor 100 to hit the ball 4 one or more times, the 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 this embodiment further includes a communication unit 102 for providing the measured measurement data to the fitting device 200. The communication unit 102 is preferably wireless so as not to interfere with the swing motion. In another aspect, the communication unit 102 may be wired. Furthermore, the swing sensor 100 may include a removable storage medium (not shown) instead of or in addition to 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 this embodiment acquires measurement data from the swing sensor 100 and executes predetermined processing. The fitting device 200 may be realized, for example, as various general-purpose computers, tablet computers, smartphones, or even dedicated terminals.

[0020] 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, based on the swing index, a first club head index and a second club head index related to the specifications of a golf club head that are suitable for the player 3. The fitting device 200 of this embodiment also includes a stratified data unit 204 in which the swing indexes are stratified and a first club head index and a second club head index are assigned to each stratification.

[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 on a tablet, etc. The storage unit 206 includes a non-volatile storage unit such as a hard disk in which the fitting program and various master data are stored, and a volatile storage unit that serves as working memory. The control unit 207 operates the above-mentioned units in accordance with the program, and is composed of, for example, a central processor (CPU). The fitting program may be stored on a recording medium and provided in the distribution process, or may be downloaded and used via an internet connection.

[0022] [Acquisition Unit] The acquisition unit 201 of the fitting device 200 is configured to be able to communicate with the communication unit 102 of the swing sensor 100, for example, wirelessly. 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 memory 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 amount that quantitatively characterizes a certain swing motion. As long as the swing index is such a feature amount, various feature amounts can be adopted without any particular limitation. In this embodiment, for example, a first swing index that is an index related to the cocking motion of the swing motion and / or a second swing index that is an index related to the rotation of the swing motion around the shaft axis is adopted as the swing index.

[0024] [First Swing Indicator (Indicator Related to Cocking)] FIG. 3 shows a portion of the player's hands and shaft 22 during a swing from the top to impact. A player's swing generally involves the steps of address, backswing, top, downswing, and impact. The address refers to the stationary state immediately before the player 3 starts swinging (see FIG. 1 ). The backswing is the movement of lifting the golf club 2 from the address. The subsequent movement of swinging the golf club 2 down is called the downswing. The timing of switching from the backswing to the downswing is the top. In this series of swing movements, the cocking is the movement of bending the player's wrist and elbow joints. The cocking is one of the important movements for imparting speed and power to the golf club head 23 and hitting the ball farther. This embodiment focuses on the cocking as a first swing indicator for quantitatively identifying a swing. The cocking is primarily detected by the swing sensor 100 as a rotational movement of the golf club 2 around the y-axis 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 during a player's swing. Time 0 indicates the moment of impact with the ball. In this embodiment, the first swing indicator is obtained as a value obtained by integrating the angular velocity ωy in the cocking direction over a certain range. The first swing indicator in this embodiment is obtained, for example, as an integral value from the top position (top) of the swing to the open cocked state, i.e., the maximum position P1 of the angular velocity ωy (the hatched portion in FIG. 4). This integral range can be changed as desired. The first swing indicator makes it possible to identify the angular change in the cocking direction during the player's swing.

[0026] [Second Swing Indicator (Indicator Related to Rotation)] The second swing indicator is an indicator related to the rotation of the swing motion around the shaft axis. Generally, the rotation of the swing motion around the shaft axis is called rotation. Rotation is a motion that mainly accompanies the rotational motion of the player's body, and serves to impart speed and power to the golf club head 23 and improve the accuracy of shots. This embodiment focuses on this rotation as a second swing indicator for quantitatively identifying the swing motion. Rotation is detected by the swing sensor 100 mainly as the rotational motion of the golf club 2 around the z-axis in the local coordinate system.

[0027] FIG. 5 shows, as measurement data, the relationship between the angular velocity about the shaft axis (i.e., the angular velocity ωz about the z-axis) and time during a player's swing. Time 0 indicates the moment of impact with the ball. In this embodiment, the second swing indicator is obtained as a value obtained by integrating the angular velocity ωz about the shaft axis over time within a certain range. The second swing indicator in this embodiment is, for example, the integral value over the range from the top position (top) of the swing to impact (the hatched portion in FIG. 5). This integral range can be changed as desired. The second swing indicator makes it possible to identify changes in the angle of rotation during the player's swing.

[0028] [Selection Unit] The selection unit 203 of the fitting device 200 can select at least one club head index relating to the specifications of a golf club head suitable for the player 3 based on the above-mentioned swing indexes (first swing index and / or second swing index).

[0029] In this specification, the specifications of a golf club head include head weight, head volume, lie angle, parameters relating to the center of gravity position (for example, center of gravity distance), moment of inertia, and the like.

[0030] Parameters relating to the position of the center of gravity of the golf club head include, for example, the distance in the toe-heel direction of a line drawn perpendicularly from the head center of gravity G to the shaft axis CL in a front view of the golf club head 23 placed in a reference state on a horizontal plane HP as shown in Figure 6 (hereinafter referred to as the center of gravity distance LB), and the distance in the face-back direction from the shaft axis CL to the head center of gravity G in a side view of the golf club head 23 placed in a reference state on a horizontal plane HP as shown in Figure 7 (hereinafter referred to as the center of gravity distance LC).

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

[0032] In this specification, the club head index uses a variable that is a weighted combination of multiple parameters described above. In a preferred embodiment, the club head index includes a first club head index, which is a first principal component obtained by performing principal component analysis on multiple parameters of the golf club head. The first principal component is expressed as a linear combination of the multiple parameters (variables) described above, and is determined so that the combination coefficient brings about the largest variation. In a more preferred embodiment, the club head index further includes a second club head index, which is a second principal component obtained by performing principal component analysis on multiple parameters of the golf club head. The second principal component is determined so that it brings about the second largest variation in a direction perpendicular to the first principal component. By using these first club head index and second club head index, it is possible to provide a club head index that takes multiple parameters of the golf club head into consideration. Furthermore, once the first club head index and second club head index suitable for the swing motion of the player 3 are identified, it is possible to easily identify one or more specific golf club heads that satisfy the above index from among various golf club heads on the market. That is, the first club head index and the second club head index are used as indexes for narrowing down a specific golf club head from among various golf club heads.

[0033] [Stratified Data Section] In the fitting device 200 of this embodiment, the selection section 203 selects a first club head index and a second club head index that are suitable for the player 3 based on the swing index of the player 3 and the stratified data section 204. FIG. 8 shows a visualized example of such a stratified data section 204. The stratified data section 204 is data prepared in advance, in which the swing indexes are stratified into a plurality of categories (in this example, classified into four categories K1 to K4), and a first club head index and a second club head index are assigned to each category. Therefore, the selection section 203 can easily select a first club head index and a second club head index that are suitable for the swing index of the player to be fitted by assigning the swing index to one of the categories in the stratified data section 204.

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

[0035] [Swing Indicator Stratification Data Section] As shown in Fig. 9, the swing indicator stratification data section 204A is generally data associating the swing movements (swing indices) of multiple players with specific golf club heads suitable for each swing movement. The swing indicator stratification data section 204A can be created, for example, by the procedure shown in Fig. 10. That is, in this embodiment, the swing indicator stratification data section is created including step S1 of measuring the swing movements of multiple players, step S2 of calculating each swing indicator from the swing movements of the multiple players, step S3 of conducting hitting tests using multiple golf club heads by the multiple players, step S4 of evaluating the quality of hit balls in the hitting tests (e.g., the quality of flight distance, height, and / or lateral deviation), step S5 of determining golf club heads suitable for each of the multiple players based on the results of the evaluation, and step S6 of stratifying the swing indices and assigning at least one golf club head suitable for each stratification based on the results of step S5.

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

[0037]

[0038] Fig. 9 is a graph showing a visualized relationship between the first swing index, the second swing index, and the golf club head suitable for the swing motion, as an example of the swing index stratification data section 204A. In Fig. 9, the horizontal axis is set to the value of the first swing index of the swing motion, and the vertical axis is set to the value of the second swing index of the swing motion. Fig. 9 also plots the swing motions identified by the first swing index and the second swing index of 29 representative players. There are three types of identification marks for the plots, each having the following meaning. White circle: Swing motion best suited to golf club head A Black circle: Swing motion best suited to golf club head B Square: Swing motion best suited to golf club head C

[0039] In this embodiment, the specifications of the golf club heads A to C are as shown in the table below.

[0040]

[0041] Characteristics of golf club head A: Among the golf club heads prepared in advance, golf club head A has a relatively large head volume. In addition, among golf club heads A to C, golf club head A has a relatively large moment of inertia (left-right MOI, up-down MOI, and axial MOI), with the left-right MOI being 5000 g cm 2 Furthermore, golf club head A has the longest center of gravity distance LC among golf club heads A to C. This golf club head A provides a sense of security when addressing the club, and has high "forgiveness" because head movement (left and right deviation) is limited on mishits.

[0042] Characteristics of golf club head B: Among golf club heads A to C, golf club head B has a relatively small head volume. Also, the moment of inertia (left-right MOI, up-down MOI, and axial MOI) of golf club head B is located between golf club head A and golf club head C. Furthermore, golf club head B has the smallest center of gravity distance LB among the candidate golf club heads. Therefore, golf club head B has excellent operability, such as making it easy to adjust the orientation of the golf club head around the shaft axis during the swing motion.

[0043] Characteristics of golf club head C: Golf club head C also has a relatively large head volume among golf club heads A to C. Furthermore, golf club head C has the smallest moment of inertia (left-right MOI, up-down MOI, and axial MOI) among golf club heads A to C. Furthermore, golf club head C has the smallest center of gravity distance LC among golf club heads A to C. Such golf club head C has a low center of gravity height on the face (also called sweet spot height), which tends to reduce the amount of backspin on the ball. Furthermore, since the axial MOI is small, it has good maneuverability.

[0044] In Fig. 9, the swing index is further stratified into six levels, L1 to L6, based on the plotted data. Each level L1 to L6 is assigned one or two golf club heads A to C that are suitable for the respective swing motion. In the example of Fig. 9, each level L1 to L6 is assigned a recommended golf club head from golf club heads A to C, as follows: Level L1: Golf club head B Level L2: Golf club heads B and C Level L3: Golf club head C Level L4: Golf club heads A and B Level L5: Golf club heads A and C Level L6: Golf club head A

[0045] Layer L1 is a group of swing motions in which both the first swing indicator and the second swing indicator are relatively large. In other words, swing motions belonging to layer L1 have large cocking motions and rotations, and therefore have relatively large opening and closing motions of the face from the top to impact. In the embodiment of Figure 9, golf club head B is assigned as being optimal for swing motions in layer L1 based on hitting tests. As described above, golf club head B has a small moment of inertia or a small center-of-gravity distance LB, and therefore has relatively good operability, and is therefore presumed to be suitable for swing motions in layer L1 in which the opening and closing motions of the face are large.

[0046] In contrast to layer L1, layer L6 is a group of swing movements in which both the first swing indicator and the second swing indicator are relatively small. In other words, the swing movements belonging to layer L6 have small cocking movements and rotations, and therefore relatively small opening and closing movements of the face from the top to impact. In the embodiment of FIG. 9 , golf club head A is assigned as optimal for the swing movements of layer L6 based on the impact test. As described above, golf club head A has a large moment of inertia or a large center-of-gravity distance LC, and therefore is presumed to be suitable for the swing movements of layer L6 in which the opening and closing movements of the face are small.

[0047] Layer L3 is a group of swing movements in which the first swing indicator is relatively large and the second swing indicator is relatively small. In other words, the swing movements belonging to layer L3 are unbalanced swings with large cocking movements but small rotations. Therefore, rotation assistance is required. In the embodiment of FIG. 9, golf club head C is assigned to layer L3 as the optimal golf club head. As described above, golf club head C has a short center-of-gravity distance LC and the smallest moment of inertia, making it a head that rotates easily, and therefore is presumed to be suitable for swing movements in layer L3.

[0048] In the swing indicator stratified data portion 204A, layer L2 is a boundary layer located between layers L1 and L3. In the hitting test, the two golf club heads B and C, which are suitable for layers L1 and L3, showed optimal results for the swing motion belonging to layer L2, and these were assigned.

[0049] In the swing indicator stratified data section 204A, layer L4 is a boundary layer located between layers L1 and L6. In the impact test, the two golf club heads A and B, which are suitable for layers L6 and L1, showed optimal results for the swing motion belonging to layer L4, and these were assigned.

[0050] Furthermore, in the swing indicator stratified data section 204A, layer L5 is a boundary layer located between layers L3 and L6. In the hitting test, the two golf club heads A and C, which are suitable for layers L6 and L3, showed optimal results for the swing motion belonging to layer L5, and these were assigned.

[0051] [Head Feature Map Data Section] Next, the head feature map data section will be described with reference to FIG. 11 . As shown in FIG. 11 , the head feature map data section 204B is roughly data obtained by performing a principal component analysis on the specifications of a plurality of golf club heads and organizing the data using the first and second principal components. The plurality of golf club heads includes at least the golf club heads A to C used to generate the swing indicator stratification data section 204A, as well as numerous golf club heads sold by various golf club manufacturers. Furthermore, since the specifications include the various items described above, in this embodiment, several of the golf club head specifications were selected, and principal component analysis was performed on them to organize items that vary similarly. In this embodiment, principal component analysis was performed using eight items from the specifications of the plurality of golf club heads: head weight, head volume, lie angle, center of gravity distance LB, center of gravity distance LC, left-right MOI, up-down MOI, and axial MOI. Table 3 shows principal component coefficients as the analysis results of the first and second principal components.

[0052]

[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, the first principal component is significantly influenced by the moment of inertia (lateral MOI, vertical MOI, and axial MOI) and the center of gravity distance LC. This first principal component is a variable that includes at least the longitudinal MOI, vertical MOI, axial MOI, and center of gravity distance LC, each of which is weighted and combined. Furthermore, the second principal component is significantly influenced by the head weight, head volume, lie angle, and center of gravity distance LB. This second principal component is a variable that includes at least the head weight, head volume, lie angle, and center of gravity distance LB, each of which is weighted and combined. Principal component analysis allows the eight specifications of many golf club heads to be condensed and classified using two variables.

[0054] Next, in this embodiment, the plurality of golf club heads that have undergone principal component analysis are organized on a two-dimensional map using the first principal component and the second principal component as their respective coordinate axes, thereby generating a head feature map data section 204B. In Fig. 11, the horizontal axis represents the first principal component, with the left side being positive and the right side being negative. The vertical axis represents the second principal component, with the upper side being positive and the lower side being negative. Furthermore, the aforementioned golf club heads A, B, and C are also plotted in this head feature map data section 204B.

[0055] Here, it can be seen that the distribution arrangement of golf club heads A, B, and C in the head feature map data section 204B of FIG. 11 is substantially consistent with the distribution arrangement of layers L6, L1, and L3 in the swing indicator stratification data section 204A of FIG. 9. Therefore, layers L1 to L6 obtained in FIG. 9 can be applied to the region in FIG. 11 in which golf club heads A, B, and C are located. Furthermore, the first principal component, which is the horizontal axis of the head feature map data section 204B of FIG. 11, can be made to correspond to the first swing index, which is the horizontal axis of the swing indicator stratification data section 204A of 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 indicator stratification data section 204A. From the above, it can be estimated that golf club heads plotted on the right side of the horizontal axis in the head feature map data section 204B of FIG. 11 are suited to swing motions in which the first swing index is large. Similarly, it can be estimated that golf club heads plotted on the upper side of the vertical axis are suited to swing movements with large second swing indicators.

[0056] In this embodiment, based on the above considerations, the vertical and horizontal axes of the head feature map data section 204B in FIG. 11 were linked to the results of the swing indicator stratification data section 204A in FIG. 9 to obtain the stratified data section 204 in FIG. 8. Therefore, once the first and second swing indicators 8 are identified, the first swing indicator and the second swing indicator can be identified from the stratified data section 204 in FIG. 8. Furthermore, the stratified data section 204 is stratified into four layers K1 to K4 by two orthogonal division lines a and b, and the swing motions of each layer K1 to K4 are assigned respective first club head indicators and second club head indicators appropriate for that layer. In FIG. 8, the vertical division line a is set, for example, so as to pass through the horizontal center of the plots of golf club heads A and C, and the horizontal division line b is set so as to pass through the plot of golf club head B.

[0057] 8, layers K1 and K2 are groups of swing movements in which the first swing index is greater than a predetermined first threshold value X. It can be seen that golf club heads with relatively small first club head indexes (first principal components) are suitable for swing movements belonging to layers K1 and K2.

[0058] Layer K1 is a group of swing movements in which the first swing index is greater than a predetermined first threshold X and the second swing index is greater than a predetermined second threshold Y. It can be seen that 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 for swing movements belonging to layer K1.

[0059] When the contribution rate of each parameter in the first and second principal components is considered, golf club heads with a small moment of inertia and a large head weight tend to be suitable for the swing motion of layer K1. Further detailed analysis revealed that golf club heads belonging to layer K1 have a left-right MOI of, for example, 4800 g cm 2 The upper and lower MOIs are preferably less than 3200 g cm. 2 Furthermore, the MOI around the axis is preferably less than 8600 g cm 2 The specific values ​​of these parameters may also be stored in association with the layer K1 in the layer-specific data section 204.

[0060] Layer K2 is a group of swing movements in which the first swing index is greater than a predetermined first threshold X and the second swing index is less than a predetermined second threshold Y. It can be seen that 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 for swing movements belonging to layer K2.

[0061] When focusing on the contribution rate of each parameter in the first and second principal components, golf club heads with a small moment of inertia and a small head weight tend to be suitable for the swing motion of layer K2. For golf club heads belonging to layer K2, it is desirable that the left-right MOI, up-down MOI, and axial MOI all fall within the same ranges as golf club heads belonging to layer K1. Specific numerical values ​​of these parameters may also be stored in association with layer K2 in the stratified data section 204.

[0062] 8, layers K3 and K4 are groups of swing movements in which the first swing index is smaller than a predetermined first threshold value X. It can be seen that golf club heads with relatively large first club head indexes (first principal components) are suitable for swing movements belonging to layers K3 and K4.

[0063] Layer K3 is a group of swing movements in which the first swing index is smaller than a predetermined first threshold X and the second swing index is larger than a predetermined second threshold 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 swing movements belonging to layer K3.

[0064] When focusing on the contribution rate of each parameter in the first and second principal components, golf club heads with a large moment of inertia and a large head weight tend to be suitable for the swing motion of layer K3. Further detailed analysis revealed that golf club heads belonging to layer K3 have a left-right MOI of, for example, 4800 g cm 2 The upper and lower MOIs are preferably 3200 g cm or more. 2 The specific values ​​of these parameters are also stored in association with the layer K3 in the layer-specific data section 204.

[0065] Layer K4 is a group of swing movements in which the first swing index is smaller than a predetermined first threshold X and the second swing index is smaller than a predetermined second threshold 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 swing movements belonging to layer K4.

[0066] When focusing on the contribution rate of each parameter in the first and second principal components, golf club heads with a large moment of inertia and a small head weight tend to be suitable for the swing motion of layer K4. For golf club heads belonging to layer K4, it is desirable that the left-right MOI, up-down MOI, and axial MOI all fall within the same ranges as golf club heads belonging to layer K3. These values ​​are also stored in association with layer K4 in the stratified data section 204.

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

[0068] The selection unit 203 refers to the stratified data unit 204 to determine which of the strata K1 to K4 the first swing index and second swing index of the player to be fitted belong to, and can select (identify) the first club head index and / or the second club head index of the golf club head assigned to the corresponding strata.

[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 may be displayed as the first club head index, and the value of the second principal component may be displayed as the second club head index. The display unit 300 may be configured as, for example, a display or a printer.

[0070] A user of the fitting device 200 can ascertain, through the display unit 300, the first club head index and / or the second club head index that are suitable for the swing motion of the person being fitted. Therefore, the user who has been fitted can, from among various golf club heads, identify a golf club head having similar specifications by referring to the value of the first principal component. Furthermore, by referring to the values ​​of the first and second principal components, they can identify a golf club head having similar specifications. The users include players, instructors, golf equipment developers, and anyone else who requires the results of a golf swing analysis.

[0071] Furthermore, as a more specific fitting, attention may be paid to the golf club head's axial MOI, left-right MOI, up-down MOI, and center-of-gravity distance LC, which have large contributions among the first club head index (first principal component), and specific ranges of these may be displayed together with the first club head index. Similarly, attention may be paid to the head weight, head volume, lie angle, and center-of-gravity distance LB, which have large contributions among the second club head index (second principal component), and specific ranges of these may be displayed together 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 (plotted in FIG. 8 ) corresponding to the layer to which the swing motion belongs may be selected and displayed.

[0072] FIG. 12 shows the results of a hitting test for a certain player using a golf club head that satisfies the first and second club head indicators selected by the fitting device 200 of this embodiment (Example). Meanwhile, FIG. 13 shows the results of a hitting test for the same player using a golf club head that does not satisfy the first and second club head indicators selected (Comparative Example). The trajectory of the ball was measured, including the distance, height, and lateral deviation. The golf clubs of the Example and Comparative Example all used the same shaft. As is clear from a comparison of FIGS. 12 and 13 , the Comparative Example showed a large variation in the distance and height of the ball. On the other hand, when hitting with a golf club head suited to a swing motion, the distance and directionality of the ball were significantly improved, confirming the usefulness of the fitting of this embodiment.

[0073] [Another embodiment: Shaft fitting] In another embodiment, following the fitting of the golf club head, the fitting of the golf club shaft (more specifically, shaft length) can be performed. As a result of various experiments conducted by the inventors, it has been found that when the rotation (second swing indicator) is small, there is little twisting during the swing motion, and the motion of opening and closing the face of the golf club head is small, but the motion of turning the golf club (the motion of swinging the golf club) tends to be large. Therefore, using a long shaft for such a swing motion, making it difficult to turn the golf club, tends to improve the directionality of the hit ball.

[0074] On the other hand, it has been found that when the rotation (second swing indicator) is large, the twisting motion during the swing motion is large, the motion of opening and closing the direction of the golf club head face is large, but the motion of returning the golf club tends to be small. Therefore, for such a swing motion, using a short shaft to make it easier to return the golf club tends to improve the directionality of the hit ball.

[0075] The fitting device 200 of this embodiment can also fit a shaft suitable for the swing motion by focusing on the magnitude of the second swing indicator related to rotation among the swing indicators measured during fitting of the golf club head in accordance with the judgment criteria described above. This process is mainly executed by the shaft length selection unit 208 ( FIG. 2 ) of the fitting device 200.

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

[0077] If the answer is N in step S10, shaft length selection unit 208 compares the second swing indicator with a predetermined second threshold value (<first threshold value) in step S12. If the second swing indicator is equal to or less than the second threshold value (Y in step S12), shaft length selection unit 208 suggests a longer shaft (step S13). Specifically, shaft length selection unit 208 causes display unit 300 to display a list of shaft lengths (in inches) or specific shaft product names that satisfy the length.

[0078] Furthermore, if the answer is 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 shaft lengths (in inches) or specific shaft product names that satisfy the length.

[0079] For example, a standard length shaft is preferably greater than 44.75 inches and less than 45.25 inches. A short shaft is preferably less than 44.75 inches. A long shaft is preferably greater than 45.25 inches.

[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 can be implemented in various modified forms within the scope of the technical idea described in the claims.

[0081] [Additional Notes] The present invention includes the following aspects.

[0082] [Present Invention 1] A golf club head fitting device comprising: an acquisition unit that acquires measurement data obtained by measuring a player's golf club swing motion using a measuring device; a calculation unit that calculates swing indicators based on the measurement data; and a selection unit that selects at least one club head indicator related to a golf club head specification suitable for the player based on the swing indicators. [Present Invention 2] The golf club head fitting device according to Present Invention 1, wherein the swing indicators include a first swing indicator that is an indicator related to a cocking motion of the swing motion, and a second swing indicator that is an indicator related to a rotation of the swing motion about the shaft axis. [Present Invention 3] The golf club head fitting device according to Present Invention 2, further comprising a stratified data unit in which the swing indicators are stratified and the at least one club head indicator is assigned to each stratification, and the selection unit selects the club head indicator suitable for the player based on the swing indicator of the player and the stratified data unit. [Aspect 4] The golf club head fitting device according to Aspect 3, wherein the at least one club head index includes a first club head index which is a first principal component obtained by principal component analysis of specifications of a plurality of golf club heads, and a second club head index which is a second principal component obtained by principal component analysis of specifications of the plurality of golf club heads. [Aspect 5] The golf club head fitting device according to Aspect 4, wherein the selection unit selects the first club head index which is relatively small when the first swing index is greater than a predetermined first threshold. [Aspect 6] The golf club head fitting device according to Aspect 4 or 5, wherein the selection unit selects the second club head index which is relatively large when the second swing index is greater than a predetermined second threshold. [Aspect 7] The golf club head fitting device according to any one of Aspects 4 to 6, wherein the selection unit selects the second club head index which is relatively small when the second swing index is smaller than a predetermined second threshold.[Invention 8] The golf club head fitting device according to any one of Inventions 4 to 7, wherein the selection unit selects the first club head index that is relatively large when the first swing index is smaller than a predetermined first threshold. [Invention 9] The golf club head fitting device according to any one of Inventions 4 to 8, wherein the selection unit selects the second club head index that is relatively large when the second swing index is larger than a predetermined second threshold. [Invention 10] The golf club head fitting device according to any one of Inventions 4 to 9, wherein the selection unit selects the second club head index that is relatively small when the second swing index is smaller than a predetermined second threshold. [Invention 11] The golf club head fitting device according to Invention 2, further comprising a shaft length selection unit that selects a shaft length based on the second swing index. [Invention 12] A golf club head fitting device according to any one of Inventions 4 to 11, wherein the first principal component is a variable obtained by weighting and combining, as the specifications, at least a moment of inertia about a vertical axis passing through the center of gravity of the head, a moment of inertia about a horizontal axis passing through the center of gravity of the head in the toe-heel direction, a moment of inertia about the shaft axis, and a center of gravity distance LC which is the distance from the shaft axis to the center of gravity of the head in the face-back direction. [Invention 13] A golf club head fitting device according to any one of Inventions 4 to 11, wherein the second principal component is a variable obtained by weighting and combining, as the specifications, at least a head weight, a head volume, a lie angle, and a center of gravity distance LB which is the distance in the toe-heel direction of a line drawn perpendicularly from the center of gravity of the head to the shaft axis. [Invention 14] The golf club head fitting device according to any one of Inventions 4 to 12, wherein the stratified data section is generated by linking a swing index stratification data section in which the swing index is stratified and an optimum golf club head is assigned to each layer, and a head feature map data section in which a plurality of golf club heads including the optimum golf club head are classified by the first principal component and the second principal component.[Invention 15] A golf club head fitting method, comprising: a step of obtaining measurement data obtained by measuring a golf club swing motion by a player using 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 with at least one club head index based on a plurality of specifications, and creating a stratified data section in which a swing index is assigned to each stratification; and a step of selecting the club head index of a golf club head suitable for the player based on the swing index and the stratification data section. [Invention 16] A golf club head fitting program that causes a computer to execute the following steps: acquiring measurement data obtained by measuring a player's swing of a golf club with a measuring device, calculating a swing index based on the measurement data, stratifying a plurality of golf club heads with at least one club head index based on a plurality of specifications and creating a stratification data section in which a swing index is assigned to each stratification, and selecting the club head index of a golf club head suitable for the player based on the swing index and the stratification data section. [Invention 17] A golf club head fitting system comprising a measuring device for measuring a player's swing of a golf club, and the fitting device described in any one of Inventions 1 to 14.

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

Claims

1. A golf club head fitting device comprising: an acquisition unit that acquires measurement data obtained by measuring a player's golf club swing motion using a measuring device; 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 a parameter of a golf club head suitable for the player based on the swing index.

2. A golf club head fitting device as described in claim 1, wherein the swing indicators include a first swing indicator which is an indicator related to the cocking motion of the swing motion, and a second swing indicator which is an indicator related to the rotation of the swing motion about the shaft axis.

3. The golf club head fitting device according to claim 2, further comprising a stratification data section in which the swing indexes are stratified and the at least one club head index is assigned to each stratification, and the selection section selects the club head index suitable for the player based on the swing index of the player and the stratification data section.

4. A golf club head fitting device as described in claim 3, wherein the at least one club head index includes a first club head index which is a first principal component obtained by principal component analysis of the characteristics of a plurality of golf club heads, and a second club head index which is a second principal component obtained by principal component analysis of the characteristics of the plurality of golf club heads.

5. The golf club head fitting device according to claim 4, wherein the selection section selects the first club head index that is relatively small when the first swing index is larger than a first predetermined threshold value.

6. The golf club head fitting device according to claim 5, wherein the selection section selects the second club head index that is relatively large when the second swing index is larger than a second predetermined threshold value.

7. The golf club head fitting device according to claim 5, wherein the selection section selects the second club head index that is relatively smaller when the second swing index is smaller than a second predetermined threshold value.

8. The golf club head fitting device according to claim 4, wherein the selection section selects the first club head index that is relatively large when the first swing index is smaller than a first predetermined threshold value.

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

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

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

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

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

14. A golf club head fitting device as described in claim 4, wherein the stratified data section is generated by linking a swing index stratification data section in which the swing index is stratified and an optimum golf club head is assigned to each layer, and a head feature map data section in which a plurality of golf club heads including the optimum golf club head are classified by the first principal component and the second principal component.

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

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

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

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