WO2015042180A1 - Club hold analysis tool - Google Patents

A club hold analysis tool is used to evaluate a club hold used in a precision club and ball sport. The club hold analysis tool senses an amount of rotation on a shaft of the club while the shaft is under a pull force, mimicking centripetal forces produced during the stroke or swing. To use the club hold analysis tool, the shaft is engaged with an arm of the club hold analysis tool; the arm is adapted to pivotally engage a substantially stationary base. The engaged shaft is then pulled to mimic the centripetal force during a stroke. A rotation sensor determines an amount of stroke rotation caused by the pull, which is visually displayed. The stroke rotation is compared to a predetermined standard to find a match. If a match is not found, a determination is made that the club hold should be modified.

CLUB HOLD ANALYSIS TOOL

Inventors: Theodore Townsend Purdy; and

Steve White

CLUB HOLD ANALYSIS TOOL

FIELD

Implementations are generally directed to a club hold analysis tool and methods using the club hold analysis tool, particularly a club hold analysis tool for precision club and ball sports.

BACKGROUND

Precision club and ball sports such as golf, polo, baseball, and hockey involve complex motions. As used herein, a ball is an object the player wishes to hit with the club, such as a golf ball, a hockey puck, a softball, baseball, polo ball, or a cricket ball.

There are many parameters that affect a player's success at the game. The

environmental parameters include the strength and direction of the wind, the temperature, humidity, and the level of friction on the ground (e.g., the type of grass on the fairway). The stroke parameters include the type of club used, placement of the player's legs on the ground and placement of one or more of the player's hands on the club (e.g., club hold), for example. The shifting of weight and speed of movement during the swing determines the amount of force by which the club hits the ball. Often times, the stroke parameter that determines the outcome of the game is the positioning of the club head relative to the ball at the time of impact because this positioning determines the trajectory of the ball. Players control the positioning of the club head at impact through their club hold during the swing. An error in the club hold dwarfs the player's skills in managing the other parameters of the game.

Amateurs and athletes alike often find it challenging to develop the skill of having a proper club hold that is effective at the end of a swing, at the time of impact with the ball. Accordingly, it would be an advantage to provide a club hold analysis tool to help players develop their skills in having a proper club hold.

SUMMARY

In certain embodiments, a club hold analysis apparatus includes an arm and a rotation sensor coupled to the arm. The arm includes a first end and an opposite, second end. The first end is adapted to removably couple with a portion of a shaft of a club; and the second end is adapted to rotatably couple to a base. The rotation sensor is configured to provide information about a rotation of the arm relative to the base when the arm is pulled away from the base.

In certain embodiments, club hold analysis tool includes a base, an arm, and an indicator coupled to the arm. The base is adapted to anchor to a ground. The arm includes a first end and an opposite, second end. The first end is adapted to couple with a portion of a shaft of a golf club; and the second end is adapted to rotatably couple to the base. The indicator is configured to provide information about a rotation of the arm relative to the base when the arm is pulled away from the base.

In certain embodiments, a method for analyzing a club hold of a player includes receiving, from a rotation sensor of a club hold analysis tool, information about a stroke rotation of a shaft of a club that is coupled to the club hold analysis tool. The method further includes comparing the information about the stroke rotation to a predetermined standard to find a match and, when the stroke rotation and the predetermined standard are unmatched, determining that a club hold of the player is to be modified. The club hold analysis tool includes an arm and a rotation sensor coupled to the arm. The arm includes a first end and an opposite, second end, wherein: the first end is adapted to couple with a portion of the shaft; and the second end is adapted to rotatably couple to a base. The rotation sensor is configured to provide information about the stroke rotation when the arm is pulled away from the base.

BRIEF DESCRIPTION OF THE DRAWINGS

Implementations will become more apparent from the detailed description set forth below when taken in conjunction with the drawings, in which like elements bear like reference numerals.

FIG. 1 A is a side view of a golf club;

FIG. IB is a close up side view of the golf head of the golf club of FIG. 1A;

FIGs. 2A-2B are each a schematic illustrating the impact of a rotated club head on a trajectory of a ball;

FIGs. 3A-3B and 4 are each a schematic illustrating the impact of a club head on a ball;

FIG. 5 A is a schematic illustrating the centrifugal and centripetal forces that act on a mass as it rotates in a plane about an axis;

FIG. 5B is a schematic illustrating the centrifugal and centripetal forces that act on a club head;

FIG. 6 is a perspective view of a club hold analysis tool;

FIG. 7 A is a side view of a club hold analysis tool;

FIG. 7B is a front view of a club hold analysis tool;

FIG. 7C is a perspective view of a club hold analysis tool;

FIG. 7D is a top view of a club hold analysis tool;

FIG. 8 is a schematic of a player using a club hold analysis tool;

FIG. 9 is a flow chart of a method for analyzing a club hold of a player; and FIGs. 1 OA- IOC are each a perspective of an exemplary trust bearing.

DETAILED DESCRIPTION

Reference throughout this specification to "one embodiment," "an embodiment," "an implementation," or similar language means that a particular feature, structure, or

characteristic described in connection with the embodiment is included in at least one embodiment of the present technology. Thus, appearances of the phrases "in one

embodiment," "in an embodiment," "in some embodiments," "in certain embodiments," and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

The described features, structures, or characteristics of the technology may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are recited to provide a thorough understanding of various embodiments. One skilled in the relevant art will recognize, however, that the technology may be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the technology.

Referring to FIGs. 1A and IB, a club, shown as golf club 100, includes a grip 104, a shaft 106, and a club head 108. Although FIGs. 1A and IB illustrate a golf club, any club used in a precision club and ball sport is applicable; for example, a club with a planar clubface such as a hockey club, or flat hitting surface such as a polo mallet, is applicable and, likewise, a club with a curved clubface, such as a baseball bat, is applicable.

The shaft 106 is illustrated with a shaft coordinate system 112 having a shaft origin at 110, a shaft x-axis 114, a shaft y-axis 116, and a shaft z-axis 118. As in the exemplary illustration, the shaft coordinate system 112 is rotated relative to a ball coordinate system 122, which has its own ball origin 120, ball x-axis 124, ball y-axis 126, and ball z-axis 128. The translational and rotational relationship between the shaft coordinate system 112 and ball coordinate system 122 is mathematically determinable through coordinate transformation equations.

In the golf example illustrated in FIG. IB, when the bottom surface 107 of the club head 108 lies substantially flat on the ground and the clubface 109 hits the center of the ball at a substantially perpendicular angle, the trajectory 130 of the ball is directed towards the target 132. However, lack of a proper relationship between the shaft 106 (and thus the clubface) and the ball, and thus their respective coordinate systems (herein referred to as "mis-positioning"), results in an error in the trajectory 130 of the ball. Referring to FIGs. 2A- 2B, schematics illustrate examples of mis-positioning of the shaft coordinate system 112 relative to the ball coordinate system 122, resulting in a missed target 132. In FIG. 2A, the shaft 106 (and consequently the clubface 109) is rotated clockwise about the shaft z-axis 118, resulting in the trajectory 202 that is right of the target 132. In FIG. 2B, the shaft 106 (and consequently the clubface 109) is rotated counterclockwise about the shaft z-axis 118, resulting in the trajectory 204 that is left of the target 132. Alternatively, or in combination, similar mis-positioning of the shaft coordinate system 112 relative to the ball coordinate system 122 can occur due to rotations about the shaft x-axis 114 and/or the shaft y-axis 116, resulting in missing the target 132 (not shown).

A spin is produced on a ball when the clubface hits the ball off center. Such a spin can result in a missed target if it is unintentional. Referring to FIG. 3A, a schematic illustrates a first positioning of the club head 108 relative to the ball 302, and consequently between the shaft coordinate system 112 and the ball coordinate system 122. Here, the club head 108 produces a force 306 that is directed perpendicularly towards the center 304 of the ball 302 such that the ball 302 takes flight without a spin. Conversely, in FIGs. 3B and 4, a rotation of the shaft 106 about the shaft y-axis 116 produces a spin on the ball 302 upon impact. In FIG. 3B a clockwise rotation 312 about the shaft y-axis 116 produces a clockwise spin 310 on the ball 302 because the direction of force 308 is to the left of the center 304 of the ball 302. In FIG. 4 a counterclockwise rotation 404 about the shaft y-axis 116 produces a counterclockwise spin 406 on the ball 302 because the direction of force 402 is to the right of the center 304 of the ball 302.

Players control the positioning of the club head 108 relative to the ball through their club hold. For example, in golf, the right and left hands of the player are stacked on top of one another on the grip 104 of the club 100 in FIG. 1A. However, even though a proper grip is implemented when holding the club 100 statically, it is difficult to maintain a proper club hold while the club 100 moves relative to the ball due in part to the centrifugal and centripetal forces acting on the club head 108 during a stroke or swing.

The effects of centrifugal and centripetal forces on a moving mass are illustrated in FIG. 5 A. Here a schematic illustrates a string 516 connected to a mass 502 at one end and attached to a center 500 at the other end. As the mass 502 rotates 514 about the center 500, a centrifugal force 508 draws the rotating mass 502 away from the center 500 of rotation. The inertia of the mass 502 produces the centrifugal force 508 as it is continually redirected. The mass 502, however, does not fly off the orbit because the string 516 is connected to the center 500. Here, the tension in the string 516 produces a centripetal force 510 that is a reactive force corresponding to the centrifugal force 508. Consequently, the centripetal force 510 keeps the mass 502 moving with a uniform speed along the circular path and it is directed along the radius of the path towards the center 500. Mathematically, the centripetal force is represented as: F = (mv²)/r, where F = centripetal force 510, m = mass 502 of the object rotating; v = tangential speed 512, and r = radius of curvature 520.

Referring to FIG. 5B, a centrifugal force 522 is produced during a stroke due to the rotation of the mass of the club, such as the mass of the club head 108, about the spine of the player. The amount of centrifugal force 522 is a function of the mass of the club head 108. The club, however, does not fly off the orbit because the player has a club hold on the club. The player's muscular and skeletal systems produce a centripetal force 520 to resist the centrifugal force 522. During a golf game, for example, the centripetal force 520 reaches significant amounts, the tangential velocity measuring to about 100 miles per hour to 120 miles per hour, for example.

However, as the player's muscular and skeletal systems produce a centripetal force 520 during the swing, the club hold of the player on a previously static club may be altered such that the positioning of the club head 108 relative to the ball is mis-positioned as previously described, for example.

Referring to FIGs. 6 and 7A-7D, schematics illustrate exemplary club hold analysis tool 600 (also referred to as a club hold analysis apparatus). The club hold analysis tool 600 includes an arm 602, a base (shown as plate 610), and a rotation sensor, such as an indicator 640 (shown in FIG. 6 as first indicator rode 640A and second indicator rod 640B). In certain embodiments, one or more of the arm 602 and the base is made of natural and/or synthetic material, such as metal (e.g., steel, aluminum ...etc.), plastic, or a combination thereof.

In some embodiments, the arm 602 has a first end 604, a body 606, and a second end 608. The orientation of the arm 602 in space is represented by an arm coordinate system 620 having an arm x-axis 622, an arm y-axis 624, and an arm z-axis 626. In FIG. 6, the body 606 of the arm 602 is illustrated as having a crescent shape. In some embodiments, the crescent shape has the following dimensions, about: 7 inches in length from the first end 604 to the second end 608; other configurations of the arm 602 are also contemplated. In some embodiments, the linear distance between the first end 604 and the second end 608 is about 5.54 inches.

The first end 604 of the arm 602 is adapted to temporarily or removably couple with a portion of a shaft of a club, such as shaft 106 of golf club 100 in FIG. 1. In certain embodiments, the first end 604 couples with one or more adaptors that each couple with a one or more preset type of club (not shown). For example, a first adaptor is configured to couple with a golf club; a second adaptor is configured to couple with a hockey club; and a third adaptor is configured to couple with a baseball club.

When the first end 604 of the arm 602 engages the portion of the shaft 106, the shaft coordinate system 1 12 (FIG. 1) remains substantially stationary relative to the arm coordinate system 620. The second end 608 of the arm 602 is adapted to rotatably (e.g., pivotally) engage the base, such as plate 610. For example, the arm 602 is adapted to couple with the base in a manner that allows rotational motion of the arm 602, about one or more of the arm x-axis 622, the arm y-axis 624, and the arm z-axis 626, relative to the base but not translate relative to the base.

For example, the second end 608 of the arm 602 includes a damper 612 that is coupled to the plate 610 via a trust bearing 614 having ball bearings within it (see also FIGs lOA-lOC). In some embodiments, the damper 612 is made of natural and/or synthetic rubber or the trust bearing 614 is made of steel.

In some embodiments, the base is ground. Alternatively, or in combination the base is the plate 610. In FIG. 6, the base is the plate 610, which has a plurality of sections (e.g., sections 616, 617, 618, and 619), each of which is substantially planar. To illustrate, the dimensions of each section is about:

In some embodiments, the sections 616, 617, 618, and 619 are affixed together in a successive series, such as by welding. Alternatively, the sections are parts of one piece of material that is bent or molded into place during the manufacturing process. Other configurations for the base are also contemplated, such as the plate 610 having a single planar section or the base being a circular disk, for example. The orientation of the base in a space is represented by a base coordinate system. In FIG. 6, the base coordinate system 630 has a base x-axis 632, a base y-axis 634, and a base z-axis 636. In FIG. 6, the base coordinate system 630 is not aligned with the ground coordinate system 660. Other configurations are also contemplated. In some embodiments the base coordinate system 630 is aligned with a ground coordinate system 660 of the ground (such as the ball coordinate system 122 of FIG. IB).

The base is adapted to become substantially stationary when in use such that the base is adapted to not rotate or translate relative to the ground. To illustrate, when substantially stationary, the base coordinate system 630 does not substantially rotate or translate relative to the ground coordinate system 660. In some embodiments, the base is stationary when anchored to the ground. In FIG. 6, the plate 610 has a plurality of apertures 642, 644, 646, and 648 that are adapted to couple with corresponding respective anchors 652, 654, 656, and 658. When the distal ends of the anchors 652, 654, 656, and 658 are each threaded through their respective apertures 642, 644, 646, and 648 and driven into the ground, the plate 610 becomes substantially stationary relative to the ground. In certain embodiments, the semi- major axis of the apertures 642, 644, 646, and 648 are each about 5/8^th of an inch and the semi-minor axis are each about l/4^th of an inch. In certain embodiments, the dimensions of the anchors 652, 654, 656, and 658 are about : 7 inches in length from a distal end to the top of its respective head; 1/2 inch in width; l/8th inch in thickness and the respective hook dimensions of the anchors are about 1 ½ inches. Alternatively, or in combination, the base uses a heavy weight to keep the base substantially stationary. For example, in some embodiments, the base is a thick iron disk that lays flat on the ground is stationary without anchors.

In certain embodiments, club hold analysis tool 600 does not include a base. Rather the arm 602 is adapted to directly anchors into the ground as the stationary base to immobilize translational motion by preventing the arm 602 from translational movement relative to the ground. However, the arm 602 is adapted to rotatably couple to the stationary base such that it can rotate about the arm coordinate system's 620 one or more axes.

The indicator 640, shown as indicator rods 640A and 640B, visually displays an orientation of the arm 602 relative to the plate 610. In FIG. 6, the indicator rod 640A is coupled (e.g., affixed) to the arm 602 at its second end 608. Here, the long axis of the indicator rod 640 A is aligned with the arm x-axis 622. The indicator rod 640B is affixed to the plate 610, remains stationary relative to the plate 610, and its long axis is aligned with the base x-axis 632. When the arm 602 is rotated at the trust bearing 614 about one or more of the arm x-axis 622, arm y-axis 624, and arm z-axis 626, the orientation of the arm 602 is visually displayed relative to the stationary indicator rod 640B. Other forms of rotation sensors which measure and/or display the orientation of the arm 602 relative to the base are also contemplated, such as a dial gauge, a digital indicator, and the like. In some embodiments, the club hold analysis tool 600 includes a calibration system. For example, referring to FIG. 7 A, a first magnet 702 is affixed to a back of the body 606 of the arm 602. A second magnet 704 is affixed to a surface of section 616 of the plate 610. The first magnet 702 and second magnet 704 are aligned in order to keep the first indicator rode 640A and second indicator rod 640B aligned when no rotational force is applied to the arm 602.

As stated previously, the pull force applied to the arm 602, such as a pull force away from the plate 610, represents the centripetal force produced during a stroke of the club. The centripetal force during a stroke is a function of the mass, such as the mass of the club head. In certain embodiments, various pull forces represent various centripetal forces produced by corresponding clubs, such as a first pull force represents a centripetal force produced when a Wood golf club is swung during a stroke and a second pull force represents a centripetal force produced when an iron golf club is swung during a stroke.

In some embodiments, the rotation sensor displays the rotation of the arm 602 relative to the plate 610 when a force directed away from the base, such as a pull force (e.g., upward force along the arm y-axis 624) is applied at the first end 604 of the arm 602. Here, the upward force simulates the centripetal force produced by a player when opposing the centrifugal force during a swing. A resistive force, such as the resistive force due to friction, of the plate 610 prevents translation of the plate 610 along a surface. At least a portion of the resistive force represents the centrifugal force produced by a rotating club.

In some embodiments, the club hold analysis tool 600 includes a force measuring sensor and/or display. For example, a strain gauge or a piezoelectric sensor is coupled to one or more of the first end 604 and second end 608 of the arm 602, such that the force measuring sensor at least one of measures and displays an amount of pull force applied to the arm 602.

Referring to FIGs. 6, 8 and 9, schematics and a flow chart illustrates a method for analyzing a club hold. At step 902, a club hold analysis tool 600 is anchored to the ground to make it substantially stationary with respect to translation along the ground. At step 904, a player 800 couples a portion of the shaft 802 of golf club 100 to the first end 604 of the arm 602, such as by engaging the shaft 802 to the first end 604 via an opening at the first end 604. In some embodiments, the entire club need not be used, rather a stick representing the shaft 802 is used. When coupled, the shaft 802 becomes substantially stationary relative to the arm 602 such that the shaft coordinate system (e.g., shaft coordinate system 1 12 in FIG. IB) is aligned, and remains stationary, relative to the arm coordinate system 620. The coupled shaft 802, however, is not stationary relative to the base or the ground because the arm 602 is adapted to allow rotation of the arm, and thus the shaft 802, about one or more arm

coordinate system 620 axes.

At step 906, the player 800 pulls on the shaft 802 to produce a pull force 806 away from the base. Here, the pull force 806 is directed along the long axis of the shaft 802, which is the shaft y-axis 116 in FIG. IB and, thus, the arm y-axis 624 of FIG. 6. This pull force 806 mimics the centripetal force produced by the player 800 when resisting the centrifugal force produced by a rotating club. In FIG. 8, the pull force 806, is opposed by a resistive force 804 produced by the force that prevents translation of the anchored club hold analysis tool 600 along the ground.

At step 908, data is received from a force measuring sensor indicating an amount of pull force 806. At step 910 the measured pull force 806 is compared to a predetermined force for a preset club head and swing to find a match. To illustrate, at step 908 the force measuring sensor indicates that the pull force 806 produced in step 906 is 40 Newtons. The 40 Newtons is compared to ranges of predetermined centripetal forces that are known to occur for various club head masses and swing speeds. For example, the pull force of 40 Newtons is matched to known centripetal forces for a 5-iron golf club swing. At step 910, a determination is made whether the 5-iron golf club swing is the swing the player 800 wishes to practice. If yes, the method 900 moves to step 912. If not, the method 900 moves from step 910 to step 914 where the player modifies the pull force based on the evaluation in step 910 and repeats steps 906 - 910 using the modified pull force.

In certain embodiments, when the player 800 pulls on the shaft 802 in step 906, the player 800 also twists the shaft 802. For example, the pull force 806 on the shaft 802 causes a counterclockwise rotation of the shaft 802 about the shaft y-axis 116 as in FIG. 4. In FIG. 8, a counterclockwise rotation of the shaft 802 causes a counterclockwise rotation of the arm 802. Consequently, the indicator rod 640A rotates counterclockwise 812 relative to indicator rod 640B, giving a visual representation of the amount of rotation of the shaft 802.

At step 912, information is received from a rotation sensor of the club hold analysis tool 600. For example, the indicator rods 640 A and 640B visually indicate an amount of stroke rotation that occurred when the pull force 806 was applied to the shaft 802. In certain embodiments, the information is electronically detected and displayed. At step 916, output of the rotation sensor, such as indicator rods 640A and 640B, is analyzed to determine if the pull force 806 caused a rotation on the arm 602 of the club hold analysis tool 600, and thus the shaft 802 and corresponding clubface. For example, the player 800, a trainer, an expert, a salesperson, or a combination thereof views the indicator rods 81 OA and 810B to determine an amount of stroke rotation of the shaft 802 along the long axis of the shaft 802. At step 918, the stroke rotation of step 916 is compared to a predetermined standard to find a match. If a match is found at step 918, then the method 900 moves from step 918 to step 922 and the club hold is determined to be accurate. If a match is not found, then method 900 moves from step 918 to step 920. At step 920, the club hold is modified in order to reduce the

discrepancy between the stroke rotation and the predetermined standard and steps 906 to 918 are repeated.

To illustrate, the player 800 uses a club hold to pull on the shaft 802 at step 906. At step 912, the indicator rods 640A and 640B indicate that the player 800 produced a first stroke rotation of 10 degrees counterclockwise relative to the base (thus relative to the ball). At step 918 the first stroke rotation of 10 degrees is compared to a predetermined standard. For example, the player 800 wishes to hit the ball without a spin, then the predetermined standard is zero degrees of rotation about the long axis of the shaft. At step 918 the 10 degrees first stroke rotation is compared to the predetermined standard of 0 degrees to find that there is no match. The player's 800 club hold is modified at step 920 to produce a second stroke rotation closer to zero degrees and steps 906 - 918 are repeated. Alternatively, if a spin is desired, the predefined standard is more than zero degrees, such as 5 degrees. Here, the club hold is modified in step 920 to produce a second stroke rotation closer to 5 degrees and steps 906 - 918 are repeated.

In certain embodiments, an electronic memory device that is electronically coupled to one or more of the rotation sensor and the force measuring sensor stores the respective stroke rotations and pull force that occur during successive repetitions of method 900. At least one of the stored stroke rotations and pull forces are visually displayed by a display electronically coupled to the electronic memory device. The visual display of the logged stroke rotations and/or pull forces is then evaluated to determine a progression or retrogression of the player 800 over a period of time.

The various steps or acts in a method or process may be performed in the order shown, or may be performed in another order. Additionally, one or more process or method steps may be omitted or one or more process or method steps may be added to the methods and processes. An additional step, block, or action may be added in the beginning, end, or intervening existing elements of the methods and processes. Based on the disclosure and teachings provided herein, a person of ordinary skill in the art will appreciate other ways and/or methods for various implements. Moreover, it is understood that a functional step of described methods or processes, and combinations thereof can be implemented by computer program instructions that, when executed by a processor, create means for implementing the one or more functional steps. For example, in certain embodiments, one or more steps of method 900 are performed by a computing device, such as a processor, that executes the program instructions. In certain embodiments, the instructions are included in computer readable medium that can be loaded onto a general purpose computer, a special purpose computer, or other programmable apparatus.

It is understood that the examples and implementations described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application.

Claims We Claim:

1. A club hold analysis apparatus comprising:

an arm including a first end and an opposite, second end, wherein:

the first end is adapted to removably couple with a portion of a shaft of a club; and the second end is adapted to rotatably couple to a base;

and

a rotation sensor coupled to the arm, wherein the rotation sensor is configured to provide information about a rotation of the arm relative to the base when the arm is pulled away from the base.

2. The club hold analysis apparatus of claim 1, further comprising an adaptor removably coupled to the first end, wherein the adaptor is configured to couple with a shaft of a preselected type of club.

3. The club hold analysis apparatus of claim 2, wherein the rotation sensor comprises:

a first rod that extends, from the second end;

and

a second rod that extends from the stationary base and is parallel to the first rod when there is no rotation of the arm relative to the base.

4. The club hold analysis apparatus of claim 1, further comprising a force measuring sensor coupled to the arm and configured to determine an amount of force applied to the arm when the arm is pulled away from the base.

5. The club hold analysis apparatus of claim 1, wherein the base is selected from the group consisting of: a ground; a planar plate; and a combination thereof.

6. The club hold analysis apparatus of claim 1, wherein the club is selected from the group consisting of: a golf club, a hockey club, a baseball club, a polo mallet, and a cricket club.

7. The club hold analysis apparatus of claim 1, further comprising an electronic memory device that logs one or more rotations of the arm relative to the base.

8. The club hold analysis apparatus of claim 7, further comprising a display that visually displays the one or more rotations.

9. The club hold analysis apparatus of claim 1, further comprising one or more anchors adapted to couple to at least one of the arm and the base for immobilizing a translational motion of the arm.

10. A club hold analysis tool comprising:

a base adapted to anchor to a ground;

an arm including a first end and an opposite, second end, wherein:

the first end is adapted to couple with a portion of a shaft of a golf club; and the second end is adapted to rotatably couple to the base;

and

an indicator coupled to the arm and configured to provide information about a rotation of the arm relative to the base when the arm is pulled away from the base.

11. The club hold analysis tool of Claim 10, wherein the arm has a crescent shape between the first end and the second end.

12. The club hold analysis tool of Claim 10, wherein at least one of the arm and the base is made of material that includes metal.

13. The club hold analysis tool of Claim 10, further comprising a force measuring sensor coupled to the arm and configured to determine an amount of force applied to the arm when the arm is pulled away from the base.

14. The club hold analysis tool of Claim 10, further comprising an electronic memory device that stores one or more rotations of the arm relative to the base.

15. The club hold analysis tool of Claim 14, further comprising a display electronically coupled to the electronic memory device, wherein the display visually displays the one or more rotations.

16. A method for analyzing a club hold of a player, the method comprising: receiving, from a rotation sensor of a club hold analysis tool, information about a stroke rotation of a shaft of a club coupled to the club hold analysis tool, wherein the club hold analysis tool comprises:

an arm including a first end and an opposite, second end, wherein:

the first end is adapted to couple with a portion of the shaft; and the second end is adapted to rotatably couple to a base;

and

a rotation sensor coupled to the arm, wherein the rotation sensor is configured to provide information about the stroke rotation when the arm is pulled away from the base;

comparing the information about the stroke rotation to a predetermined standard to find a match; and when the stroke rotation and the predetermined standard are unmatched, determining that a club hold of the player is to be modified.

17. The method of claim 16, further comprising storing, at a computing device, one or more stroke rotations.

18. The method of claim 16, further comprising receiving, from a force measuring sensor of the club hold analysis tool, data about an amount of force applied to the arm when the arm is pulled away from the base.

19. The method of claim 18, further comprising:

comparing the amount of force to a predetermined force for a preset club head to find a

match; and

displaying when a match is found.

20. The method of claim 16, wherein at least one of the receiving, comparing, and the determining steps is performed by a computing device.