Transducing and analyzing forces for instrumented sporting devices and the like

• US 5,209,483 A
• Filed: 04/19/1991
• Issued: 05/11/1993
• Est. Priority Date: 04/19/1991
• Status: Expired due to Term

• Current Assignee: G & A Associates
• Original Assignee: GH Associates Incorporated
• Inventors: Abbot, Philip A., Gedney, Charles J.
• Primary Examiner(s): HARRISON, JESSICA
• Application Number:
  US07/687,830
• Time in Patent Office: 753 Days
• Field of Search: 273/183 R, 273/183 D, 273/184 R, 273/185 R, 273/186 R, 273/186 A, 273/193 R, 73/862.04, 73/862.66, 73/488, 73/489, 73/490, 73/763, 73/767, 73/768, 73/770, 73/774
• US Class Current: 473/223
• CPC Class Codes: A63B 2220/53 Force of an impact, e.g. blow or punch
• CPC Class Codes: A63B 69/0026 for ice-hockey
• CPC Class Codes: A63B 69/362 electrical or electronic
• CPC Class Codes: A63B 69/3632 Clubs or attachments on clubs, e.g. for measuring, aligning A63B69/3614 takes precedence; clubs for swinging exercises in general A63B15/00
• CPC Class Codes: G01L 5/0052 measuring forces due to impact G01L5/0061, G01L5/14 take precedence; impact testing of structures G01M7/08; impact testing of material G01N3/00
• CPC Class Codes: G01L 5/16 for measuring several components of force

Abstract

A device that characterizes the trajectory followed by a movable object after a piece of sporting equipment comes into contact with the movable object, e.g., by identifying velocity, the distance that the object would travel if unobstructed in standard ideal conditions, the curvature of the path travelled by the object, the direction of travel of the object, or the direction or magnitude of spin of the object. The device includes at least one force sensor element arranged to be located on the piece of sporting equipment, which is held or worn by a user. The sensor element detects at least a component of the force of contact between the piece of sporting equipment and the movable object. The sensor element provides a signal representing the intensity of the component of the force of contact when the contact occurs. An electrical processing circuit is arranged to receive the signal from the sensor element and to process the signal to produce an output characterizing the trajectory of the movable object. A user notification device is arranged to receive the output from the electrical processing circuit and to present to the user information characterizing the trajectory.

Claims

1. A device, designed for use in conjunction with a piece of sporting equipment held or worn by a user, for characterizing a trajectory followed by a movable object after an object-striking face of said piece of sporting equipment comes into contact with said movable object, comprising

an impact sensor comprising a plurality of impact force sensing elements, said impact sensor being incorporated into said object-striking face of said piece of sporting equipment in a manner such that each of said impact force sensing elements can experience compressional or tensile force upon impact between said piece of sporting equipment and said movable object, each of said impact force sensing elements providing a respective signal representing the intensity of said compressional or tensile force when said contact between said movable object and said piece of sporting equipment occurs, said plurality of impact force sensing elements being arranged to be positioned at differing locations on said piece of sporting equipment at which said impact force sensing elements receive differing compressional or tensile forces due to impact between said piece of sporting equipment and said movable object,

an electrical processing circuit arranged to receive said signals from said impact force sensing elements and to process said signals to produce an output characterizing said trajectory of said movable object, and

a user notification device arranged to receive said output from said electrical processing circuit and to present to said user information characterizing said trajectory, said information characterizing said trajectory comprising the direction of travel of said movable object relative to said piece of sporting equipment.

2. A device in accordance with claim 1 wherein said information characterizing said trajectory further comprises the distance that said movable object would travel, relative to the point of said contact with said piece of sporting equipment, if said trajectory were unobstructed.

3. A device in accordance with claim 2, wherein said electrical processing circuit comprises

a peak detector that receives said signal from one of said impact force sensing elements and produces an output representing the maximum amplitude of said signal, and

a level converter that receives said output of said peak detector and produces an output that represents said distance that said movable object would travel assuming that said movable object has a given mass and a given drag curve, said level converter comprising a memory that associates distances with possible values of said output of said peak detector.

4. A device in accordance with claim 1, wherein said information characterizing said trajectory further comprises velocity.

5. A device in accordance with claim 4, wherein said velocity comprises the initial velocity of said movable object after contact between said piece of sporting equipment and said movable object.

6. A device in accordance with claim 4, wherein said velocity comprises the velocity of said piece of sporting equipment immediately prior to contact between said piece of sporting equipment and said movable object, the initial velocity of said movable object after contact being a function of said velocity of said piece of sporting equipment before contact.

7. A device in accordance with claim 4, wherein said electrical processing circuit comprises

a peak detector that receives said signal from one of said impact force sensing elements and produces an output representing the maximum amplitude of said signal, and

a level converter that receives said output of said peak detector and produces an output that represents said velocity of said movable object assuming that said movable object has a given mass.

8. A device in accordance with claim 1 wherein said electrical processing circuit comprises a comparator that receives signals from at least two of said plurality of impact force sensing elements and produces an output that represents the sign or magnitude of the difference between said signals, the sign and magnitude of the difference between said signals identifying the direction of travel of said movable object.

9. A device in accordance with claim 8, wherein said at least two of said plurality of impact force sensing elements are arranged to be located on opposing sides of a location on said piece of sporting equipment at which said movable object is most likely to come into contact with said piece of sporting equipment.

10. A device in accordance with claim 8, further comprising

at least one plate arranged and configured to be positioned on said piece of sporting equipment in a manner such that said plate transmits a shear component of impact force between said movable object and said piece of sporting equipment, as a compressional force to at least a first of said plurality of impact force sensing elements only if said shear component of impact force is in a first direction, and as a compressional force to at least a second of said plurality of impact force sensing elements only if said shear component of impact force is in a second direction,

said comparator receiving signals from said at least a first of said plurality of impact force sensing elements and said at least a second of said plurality of impact force sensing elements, and producing an output that represents the sign or magnitude of the difference between said signals.

11. A device in accordance with claim 1 wherein

said piece of sporting equipment comprises a golf club,

said movable object comprises a golf ball, and

said impact force sensing elements are arranged to be positioned at differing locations on the face of the head of said golf club.

12. A device, designed for use in conjunction with a piece of sporting equipment, for characterizing the spin of a movable object with which an object-striking force sensing elements, said impact sensor being incorporated into said object-striking face of said piece of sporting equipment in a manner such that said impact force sensing elements can experience compressional or tensile force upon impact between said piece of sporting equipment and said movable object, said impact force elements providing a plurality of respective signals representing the intensity of said compressional or tensile force when said contact between said movable object and said piece of sporting equipment occurs, said plurality of impact force sensing elements being arranged to be positioned at differing locations on said piece of sporting equipment at which said impact force sensing elements receive differing compressional or tensile forces due to impact between said piece of sporting equipment and said movable object,

an electrical processing circuit arranged to receive said signals from said impact force sensing elements and to process said signals to produce an output characterizing said spin of said movable object, and

a user notification device arranged to receive said output from said electrical processing circuit and to present to said user information characterizing said spin.

13. A device in accordance with claim 12 wherein said information characterizing said spin comprises the direction of said spin of said movable object.

14. A device in accordance with claim 12 wherein said information characterizing said spin comprises the magnitude of said spin of said movable object.

15. A device in accordance with claim 12 wherein said information characterizing said spin characterizes curvature of a path travelled by said movable object after said piece of sporting equipment comes into contact with said movable object.

16. A device in accordance with claim 12, wherein

said electrical processing circuit comprises a comparator that receives signals from at least two of said plurality of impact force sensing elements and produces an output that represents the sign or magnitude of the difference between said signals, the sign of the difference between said signals identifying the direction of spin of said movable object and the magnitude of the difference between said signals identifying the magnitude of spin of said movable object, and

said at least two of said plurality of impact force sensing elements are arranged to be located on opposing sides of a location on said piece of sporting equipment at which said movable object is most likely to come into contact with said piece of sporting equipment.

17. A device in accordance with claim 12, wherein

said electrical processing circuit comprises a comparator that receives signals from at least two of said plurality of impact force sensing elements and produces an output that represents the sign or magnitude of the difference between said signals, the sign of the difference between said signals identifying the direction of spin of said movable object and the magnitude of the difference between said signals identifying the magnitude of spin of said movable object,

said device further comprises at least one plate arranged and configured to be positioned on said piece of sporting equipment in a manner such that said plate transmits a shear component of impact force between said movable object and said piece of sporting equipment, as a compressional force to at least a first of said plurality of impact force sensing elements only if said shear component of impact force is in a first direction, and as a compressional force to at least a second of said plurality of impact force sensing elements only if said shear component of impact force is in a second direction, and

said comparator receives signals from said at least a first of said plurality of impact force sensing elements and said at least a second of said plurality of impact force sensing elements, and produces an output that represents the sign or magnitude of the difference between said signals.

18. A device in accordance with claim 12 wherein

said piece of sporting equipment comprises a golf club,

said movable object comprises a golf ball, and

said impact force sensing elements are arranged to be positioned at differing locations on the face of the head of said golf club.

19. Sporting apparatus, comprising

a piece of equipment held or worn by a user, and

a device for characterizing a trajectory followed by a movable object after an object-striking face of said piece of equipment comes into contact with said movable object, said device comprising

an impact sensor comprising a plurality of impact force sensing element, said impact sensor being incorporated into said object-striking face of said piece of equipment in a manner such that each of said impact force sensing elements can experience compressional or tensile force upon impact between said piece of equipment and said movable object, each of said impact force sensing elements providing a respective signal representing the intensity of said compressional or tensile force when said contact between said movable object and said piece of equipment occurs, said plurality of impact force sensing elements being arranged to be positioned at differing locations on said piece of sporting equipment at which said impact force sensing elements receive differing compressional or tensile forces due to impact between said piece of sporting equipment and said movable object,

an electrical processing circuit arranged to receive said signals from said impact force sensing elements and to process said signals to produce an output characterizing said trajectory of said movable object, and

a user notification device arranged to receive said output from said electrical processing circuit and to present to said user information characterizing said trajectory, said information characterizing said trajectory comprising the direction of travel of said movable object relative to said piece of equipment.

20. Sporting apparatus, comprising

a piece of equipment designed for sporting purposes, and

a device for characterizing the spin of a movable object with which an object-striking face of said piece of equipment comes into contact, comprising

an impact sensor comprising a plurality of impact force sensing elements, said impact sensor being incorporated into said object striking face of said piece of equipment in a manner such that said impact force sensing elements can experience compressional or tensile force upon impact between said piece of equipment and said movable object, said impact force sensing elements providing a plurality of respective signals representing the intensity of said compressional or tensile force when said contact between said movable object and said piece of equipment occurs, said plurality of impact force sensing elements being arranged to be positioned at differing locations on said piece of sporting equipment at which said impact force sensing elements receive differing compressional or tensile forces due to impact between said piece of sporting equipment and said movable object,

an electrical processing circuit arranged to receive said signals from said impact force sensing elements and to process said signals to produce an output characterizing said spin of said movable object, and

a user notification device arranged to receive said output from said electrical processing circuit and to present to said user information characterizing said spin.

21. A shear force transducer comprising

a first plate having a plurality of protrusions extending from one side thereof,

a second plate positioned substantially parallel to said first plate and having a plurality of protrusions extending from one side thereof, said protrusions extending from said second plate being interspaced with respect to said protrusions extending from said first plate,

a plurality of sensor elements, each of said sensor elements being located between a protrusion extending from said first plate and a protrusion extending from said second plate, each of said sensor elements providing a signal representing the intensity of force between said element and said protrusions when a shear force is applied to one of said plates, said shear force applied to said one of said plates being in a direction parallel to said one of said plates and said force between each of said sensor elements and said protrusions being in a direction parallel to said one of said plates, and

a processing circuit arranged to receive said signal from at least a first of said sensor elements and said signal from at least a second of said sensor elements, said at least a first of said sensor elements experiencing a compressional force only when a shear force is applied to one of said plates in a first direction, said at least a second of said sensor elements experiencing compressional force only when a shear force is applied to said one of said plates in an opposite direction, said processing circuit producing an output identifying the sign or magnitude of said shear force.

22. A device, designed for use in conjunction with a piece of sporting equipment held or worn by a user, for characterizing a trajectory followed by a movable object after an object-striking face of said piece of sporting equipment comes into contact with said movable object, comprising

an impact sensor comprising at least one impact force sensing element, said impact sensor being incorporated into said object-striking face of said piece of sporting equipment in a manner such that said impact force sensing element can experience compressional or tensile force upon impact between said piece of sporting equipment and said movable object, said impact force sensing element providing a signal representing the intensity of said compressional or tensile force when said contact between said movable object and said piece of sporting equipment occurs,

an electrical processing circuit arranged to receive said signal from said impact force sensing element and to process said signal to produce an output characterizing said trajectory of said movable object, said electrical processing circuit comprising a peak detector arranged to detect a peak value of said signal from said impact force sensing element, said electrical processing circuit further comprising a memory arranged to receive said peak value as an input and preprogrammed with experimentally determined values that relate each of a plurality of possible peak values of said signal with a respective output value characterizing said trajectory,

a user notification device arranged to receive said output from said electrical processing circuit and to present to said user information characterizing said trajectory.