Patent Publication Number: US-2009221388-A1

Title: Feedback-providing sporting goods item

Description:
BACKGROUND 
     When using a sporting goods item, such as a ball bat, hockey stick, or golf club, it is often beneficial for a player to obtain feedback regarding his or her performance. When a player swings a ball bat and strikes a pitched ball, for example, it is generally beneficial for the player to know where on the bat the ball impact occurred. This is often difficult for a player to determine, however, due to the speed of the swing and the player&#39;s focus on the moving ball. 
     A player may be unaware, for example, that he or she consistently strikes a pitched ball with a portion of the ball bat located between the handle and the “sweet spot” of the bat barrel. While striking a ball with this portion of the bat may provide adequate performance in some circumstances, peak performance is not achieved. The player may not realize, however, that he or she is not making optimal contact. As a result, the player may never make the swing adjustments necessary to consistently strike a ball at or near the sweet spot of the bat barrel. 
     Players often use swing coaches or swing instructors who provide feedback regarding the quality and location of an impact with a ball bat or other sporting goods item. The use of such an instructor can be expensive, however, and requires that the instructor be present for the player to obtain meaningful feedback. Furthermore, a professional swing coach or instructor often focuses more on a player&#39;s swing mechanics than on the location of impact against a bat or other impact object (which, regardless, is difficult to determine with the naked eye). 
     Sophisticated computer programs and equipment have also been developed to provide feedback to a player regarding swing performance. This equipment is typically expensive, however, and the player typically has to go to a designated location to use the equipment. Thus, it is often difficult, time-consuming, and/or expensive for a player to obtain meaningful feedback regarding his or her swing quality. 
     SUMMARY 
     A sporting goods item, such as a ball bat, includes a sensor located on or in a body of the item. The sensor detects vibrations produced by an object&#39;s impact against the item. The detected vibrations are used to determine the quality or location of the impact, or other information about the impact. An optical and/or audible feedback element located on or in the item visually and/or audibly provides information about the impact. 
     Other features and advantages will appear hereinafter. The features described above can be used separately or together, or in various combinations of one or more of them. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings, wherein the same reference number indicates the same element throughout the views: 
         FIG. 1  is a perspective view of a ball bat including an optical display system, according to one embodiment. 
         FIG. 2  is a perspective view of the tapered section of the ball bat shown in  FIG. 1  with a portion cutaway to expose components of the optical display system. 
         FIG. 3  is a schematic side view of a ball bat indicating the approximate locations of the nodes and the anti-node of the second mode of vibration in the ball bat. 
     
    
    
     DETAILED DESCRIPTION 
     Various embodiments of the invention will now be described. The following description provides specific details for a thorough understanding and enabling description of these embodiments. One skilled in the art will understand, however, that the invention may be practiced without many of these details. Additionally, some well-known structures or functions may not be shown or described in detail so as to avoid unnecessarily obscuring the relevant description of the various embodiments. 
     The terminology used in the description presented below is intended to be interpreted in its broadest reasonable manner, even though it is being used in conjunction with a detailed description of certain specific embodiments of the invention. Certain terms may even be emphasized below; however, any terminology intended to be interpreted in any restricted manner will be overtly and specifically defined as such in this detailed description section. 
     Where the context permits, singular or plural terms may also include the plural or singular term, respectively. Moreover, unless the word “or” is expressly limited to mean only a single item exclusive from the other items in a list of two or more items, then the use of “or” in such a list is to be interpreted as including (a) any single item in the list, (b) all of the items in the list, or (c) any combination of items in the list. 
     The feedback systems described herein may be used in any suitable sporting good or impact object. For example, an optical or audible feedback system may be included in a ball bat, golf club, hockey stick, tennis racquet, archery bow, or other suitable item. For ease of illustration, a ball bat will be used as the primary example throughout this detailed description section. It is understood, however, that the feedback systems described herein may be incorporated in any suitable sporting good or impact object. 
     Turning now in detail to the drawings, as shown in  FIG. 1 , a baseball or softball bat  10 , hereinafter collectively referred to as a “ball bat” or “bat,” includes a handle  12 , a barrel  14 , and a tapered section  16  joining the handle  12  to the barrel  14 . The free end of the handle  12  includes a knob  18  or similar structure. The barrel  14  is preferably closed off by a suitable cap  20  or plug. The interior of the bat  10  is preferably hollow, allowing the bat  10  to be relatively lightweight so that ball players may generate substantial bat speed when swinging the bat  10 . 
     The ball bat  10  may be a training bat, a bat constructed for use in sanctioned league play, or a toy bat or otherwise unofficial bat. The ball bat  10  may be made of one or more fibrous composite, metal, wood, plastic, or other suitable materials. The ball bat  10  may be a one-piece construction or may include two or more separate attached pieces (e.g., a separate handle and barrel), as described, for example, in U.S. Pat. No. 5,593,158, which is incorporated herein by reference. 
     In one embodiment, the ball bat  10  includes an optical display system  21 . The optical display system  21  may be encapsulated, embedded, or otherwise contained in a housing  23  positioned around and secured to the ball bat  10 . The housing  23  may be a molded plastic, rubber, or other suitable material. The housing  23  may be positioned on the tapered section  16 , handle  12 , or any other suitable region of the ball bat  10 . In an alternative embodiment, one or more components of the optical display system  21  may be encapsulated in the bat material itself, such as in one or more fibrous composite layers of the ball bat. The optical display system  21  may alternatively be attached to the ball bat  10  in any other suitable manner. 
     In one embodiment, the ball bat  10  includes an indented region into which the housing  23  may be positioned or inserted after the body of the bat  10  is constructed. Thus, the optical display system  21  may optionally be manufactured separately from the ball bat  10 , and may be applied to the bat  10  during the final stages of bat manufacturing (or after manufacturing is completed). After insertion, the radially outer surface of the housing  23  is preferably flush, or substantially flush, with the radially outer surfaces of longitudinally neighboring regions in the ball bat  10 , such that a relatively smooth transition is provided between the housing  23  and the longitudinally neighboring regions. In one embodiment, the indented region has a depth, and the housing  23  has a corresponding thickness, of approximately 0.20 to 0.25 inches. The indented region and the housing  23  may, of course, have any other suitable dimensions. 
     In one embodiment, the housing  23  is a rubber or otherwise elastic sleeve that can be pulled or slid up from the handle end of the ball bat  10  into the indented region of the ball bat  10 . Alternatively, the housing  23  may be made of a plastic or similar material and may include an opening in the circumferential direction such that it includes two facing free ends. The free ends may be pulled away from each other such that the housing  23  can be snapped or forced into place over the indented region. The free ends may optionally include complementary mating tabs or other mating elements for providing a firm engagement between the free ends after insertion of the housing  23  into the indented region. The housing  23  may optionally include a living hinge or similar mechanism for allowing the free ends to be separated into an open position. After the housing  23  is positioned over the indented region of the ball bat  10 , the free ends may be brought together into a closed position. 
     The optical display system  21  includes one or more sensors  22 . For ease of description, a single sensor  22  will be described herein. The sensor  22  may be an accelerometer or similar device that detects acceleration or velocity in the ball bat, a mode sensor trigger that detects vibrations in the ball bat, or any other suitable sensing device. Additionally or alternatively, an impact, inertia, or displacement sensing element may be used. The sensor  22  preferably includes, or is electrically connected to, a processor. The sensor  22  may, for example, be incorporated in a MEMS (micro electromechanical system) processor device or chip. 
     The sensor  22  detects vibrations in the ball bat  10 , such as those produced when the bat  10  impacts a ball. The use of one or more sophisticated sensors  22 , such as a MEMS sensor, for example, may allow for additional or alternative measurements. Hit frequency, maximum hit energy, swing velocity, and other suitable parameters, for example, may be measured using one or more appropriate sensing devices. For ease of description, vibration detection will primarily be described herein. 
     Based on the intensity of the vibrations, the sensor  22  determines approximately where against the ball bat  10  the impact occurred. Displacement or vibrations are generally minimal at the primary nodes of vibration in the ball bat  10 , for example, at the “sweet spot” of the barrel  14 , which is typically at or near the center of percussion of the ball bat  10 . Conversely, displacement or vibrations are generally greatest at the anti-nodes of vibration in the ball bat  10 . When a ball impacts the ball bat  10  away from the primary nodes of vibration, a portion of the incident ball energy establishes the vibration modes of the ball bat. The second mode of vibration is of particular interest, since the second mode of vibration exhibits a range of fundamental frequencies coincident with those directly felt by a batter (e.g., approximately 600 Hz). 
     It is generally preferable, therefore, to position the sensor  22  at or near the anti-node of the second mode of vibration, which typically occurs at or near the tapered section  16  of the ball bat  10 .  FIG. 3  illustrates the deformation profile of a typical ball bat in its second mode of vibration. The points where the dotted lines cross indicate the locations of the primary vibration nodes of the second mode of vibration in the ball bat  10 . The peaks, or farthest spaced apart points, of the dotted lines indicate the approximate longitudinal location of the anti-node of the second mode of vibration in the ball bat  10 . In a preferred embodiment, the sensor  22  is positioned at or near this location. 
     The sensor  22  is preferably electrically connected, via one or more wires or metal strips  25 , to a light assembly  26 , a liquid crystal display (“LCD”), or other visual display on or in (or separate from) the housing  23 . The sensor  22  may alternatively be wirelessly connected to the light assembly  26  via any suitable wireless connection technology. The light assembly  26  may include one or more LEDs  27  (“light emitting diodes”), lamps, light bulbs, or other suitable lighting devices that are electrically connected to the sensor  22 . The light assembly  26  is preferably covered by a transparent (or translucent) strip  29 , or enclosed within a transparent (or translucent) casing, through which the LEDs  27  may be viewed by an observer. In one embodiment, the entire housing  23  may be transparent or translucent. 
     In one embodiment, multiple LEDs  27  or other lights are positioned around the circumference of the tapered section  16 , handle  12 , or barrel  14  (preferably away from the sweet spot) of the ball bat  10 . Additionally or alternatively, LEDs  27  may be located in a transparent or translucent cap  20  or knob  18  on the ball bat  10 . In one embodiment, LEDs  27  may be positioned in the tapered section  16 , the cap  20 , and the knob  20  (or the handle  12 ), and may be triggered simultaneously or in a predetermined sequence to provide feedback about an impact against the ball bat  10 , as further described below. 
     Each of the LEDs  27  is preferably capable of illuminating in a variety of colors or intensities. Alternatively, certain LEDs  27  may illuminate in one or more colors or intensities, while other LEDs  27  may illuminate in one or more different colors or intensities. In this manner, different colors or intensities of light, or different flashing sequences, may be used to indicate different qualities or properties of impacts against the ball bat  10 . 
     The sensor  22  is preferably electrically connected to a power source, such as one or more batteries  24 . The power source may alternatively be a piezoelectric strip, which is energized via deformation in the ball bat  10 , or may be any other suitable source of power. The batteries  24  may be standard AAA batteries, disc batteries, or any other suitably sized batteries. The batteries  24  provide power to the sensor  22 , which in turn activates the light assembly  26 , as further described below. The batteries are preferably removable, via an access door or panel  28 , so they may be replaced after they expire. The access panel  28  may be secured in place on or in the housing  23  via a screw  30 , pin, latch, or other suitable mechanism. The panel  28  may be hinged or may be completely removable. 
     In one embodiment, if the sensor  22  detects little or no vibration in the ball bat  10  after impact with a ball, for example, the sensor  22  signals one or more LEDs  27  to illuminate in a color (e.g., green) indicating that “good contact” or a high quality impact has occurred. If, conversely, the sensor  22  detects significant vibration after impact with a ball, the sensor  22  signals one or more LEDs  27  to illuminate in a color (e.g., red) indicating that “poor contact” or a low quality impact has occurred. 
     As used herein, impact “quality” refers to the amount of vibration produced by the impact (with lower vibration corresponding to higher quality), or to the location of the impact relative to, or the distance of the impact from, the sweet spot (with greater distance corresponding to lower quality), or to any other useful feedback about the impact. In one embodiment, the magnitude of the displacement, velocity, or acceleration of vibrations caused by impacts at a variety of non-node locations may be calibrated against a node impact. This information may then be used to determine the approximate distance from the sweet spot (or other node) that future impacts occur against the ball bat  10 . 
     In one embodiment, a variety of colors or flashing sequences may be used to indicate varying degrees of impact quality. For example, green light may be used to indicate a sweet spot impact that produces little or no vibration; yellow light may be used to indicate an impact relatively close to the sweet spot that produces more vibration than a “green light hit;” orange light may be used to indicate an impact farther from the sweet spot that produces more vibration than a “yellow light hit;” and red light may be used to indicate an impact even farther from the sweet spot (for example, at or close to the anti-node of the second mode of vibration) that produces more vibration than an “orange light hit.” Differing colors or flashing sequences may additionally or alternatively be used to indicate whether an impact occurred between the sweet spot and the free end of the barrel, or between the sweet spot and the tapered section of the ball bat. Any desired combination of light indicators or flashing sequences may be used. 
     In another embodiment, one or more pressure contact switches or sensors may additionally or alternatively be located on or in the ball bat  10  for determining where impact occurs against the ball bat  10 . The pressure contact switches are preferably electrically or wirelessly connected to the light assembly  26 . In one embodiment, each pressure contact switch is configured to send, upon impact at or near the pressure contact switch&#39;s location, a signal to the light assembly  26  that causes one or more of the LEDs  27  to illuminate in a color corresponding to the location of the pressure contact switch. In this manner, different colors or intensities of light may be used to indicate impacts that occur at or near pressure contact switches positioned in a variety of locations. 
     For example, if impact occurs at or near a first pressure contact switch located at the sweet spot of the barrel  14 , the first pressure contact switch may send a signal to the light assembly  26  causing one or more LEDs  27  to illuminate in a green color. If impact occurs at or near a second pressure contact switch located distally from the sweet spot, conversely, the second pressure contact switch may send a signal to the light assembly  26  causing one or more LEDs  27  to illuminate in a red color. Similarly, pressure contact switches located at varying bat locations could be configured to send signals causing one or more of the LEDs  27  to illuminate in a variety of colors or flashing sequences indicative of the quality of an impact. 
     The pressure contact switches may be encapsulated in the bat material, such as in the composite layers of a fibrous composite ball bat. Alternatively, the pressure contact switches may be embodied in a separate cover or over-wrap, which may be secured to the outside of any ball bat. For example, the pressure contact switches may be housed in a thin nylon or plastic cover including ends that mate via hook and loop material, or via any other suitable connector. In this manner, the cover may be readily removed from and attached to a ball bat, and may be used on multiple ball bats. 
     In another embodiment, an audible response element, electrically connected to the sensor  22 , may be used in addition to, or as an alternative to, the light assembly  26 . The audible response element may optionally be included in the housing  23 . The audio response element may be a piezoelectric speaker or any other suitable audio device. The audible response element may produce a first sound when impact occurs at or near the sweet spot, and a second, different sound when impact occurs distally from the sweet spot. Any desired number of different sounds may be used to indicate different impact locations. Additionally or alternatively, the audible response element may produce varying numbers of “beeps” or other sounds to indicate different impact locations. Any other suitable audible sounds or patterns of sounds may be used to indicate different impact locations. 
     In another embodiment, the optical display system  21  illuminates a display of words or other visual elements that indicate the quality of an impact against the ball bat  10 . The optical display system  21  may, for example, illuminate the words “nice hit” or “poor hit,” depending on the location of the impact relative to the sweet spot of the bat barrel  14 . This may be achieved by positioning LEDs  27  or other lights behind a transparent sheet including opaque outlines of the desired letters or words, or in any other suitable manner. Any desired words or other visual indicators may be included in the optical display. 
     An optical feedback system, operating substantially in the manner described above, may be included in other impact objects, as well. For example, an optical feedback system may be included in a golf club, hockey stick, archery bow, or other suitable object. 
     In a golf club, a sensor may be embedded or otherwise secured in the club head or shaft for detecting vibrations in the club head produced by an impact against the club head. Other swing or impact parameters may additionally or alternatively be measured, as described above. The power source may be embedded or otherwise secured in the club head or shaft, while a light system or other visual display may be included on a top surface of the club head or in any other suitable location. 
     In a hockey stick, a sensor may be embedded or otherwise secured in the blade or stick shaft for detecting vibrations in the blade produced by an impact against the blade. Other swing or impact parameters may additionally or alternatively be measured, as described above. The power source may be embedded or otherwise secured in the blade or the stick shaft, while a light system or other visual display may be included on a top surface of the blade or in any other suitable location. 
     In an archery bow, a sensor may be embedded or otherwise secured in the bow to detect the displacement energy produced by an arrow release. The power source may be embedded or otherwise secured in any suitable location of the bow. The light system or other visual display may be located in the riser of the bow between the sites and the limb, or in a transparent arrow guide, or in any other suitable location. 
     Any of the above-described embodiments may be used alone or in combination with one another. While several embodiments have been shown and described, various changes and substitutions may of course be made, without departing from the spirit and scope of the invention. The invention, therefore, should not be limited, except by the following claims and their equivalents.