Method and apparatus for sport swing analysis system

Abstract

A sports swing analysis system employs triangulation techniques to determine the height of a swung golf club.

1 . A method of determining the height of a swung golf club head having retroreflective material coupled to it, comprising the steps of: 
 (A) emitting a light toward as location in a path of the swung golf club;    (B) receiving light reflected from the retroreflective material; and    (C) generating at least one signal in response to the reception of light reflected from the club head,    (D) employing light reflected from a light source that is substantially perpendicular to the flight path of a golf club head and light reflected from a light source that is at an angle between perpendicular and parallel to that of the flight path of a golf club head to determine the height of the swinging golf club head.    
   
   
       2 . The method of  claim 1  wherein the steps of determining the golf club head height comprises the steps of: 
 (E) determining the time between light level transitions corresponding to the points of intersection of the retroreflective material and light beamed from a transmitter that is oriented substantially perpendicular to the flight path of a golf club head and light level transitions reflected from a light source beamed at a known angle between perpendicular and parallel to that of the flight path of a golf club head;    (F) employing the club head speed and the time between light level transitions to determine the distance between the points of intersection with perpendicular and angled beams; and    (G) employing the angle and distance between points of intersection to determine the club head height.    
   
   
       3 . The method of  claim 2  wherein the step of activating non-trigger transmitters and receivers further comprises the step of: 
 (H) activating the transmitters at a high power level.    
   
   
       4 . A golf swing analysis system comprising: 
 a photoemitter configured to emit light toward a location in a path of the swung golf club;    a photoreceiver configured to receive light from the reflective material;    a processor configured to generate at least one signal in response to the reception of light reflected from the club head, and to employ light reflected from a light source that is substantially perpendicular to the flight path of a golf club head and light reflected from a light source that is at an angle between perpendicular parallel to that of the flight path of a golf club head to determine the height of the swinging golf club head.    
   
   
       5 . The system of  claim 4  wherein the processor is further configured to: 
 determine the time between light level transitions corresponding to the points of intersection of the reflective material and light beamed from a transmitter that is oriented substantially perpendicular to the flight path of a golf club head and light level transitions reflected from a light source beamed at a known angle between perpendicular and parallel to that of the flight path of a golf club head;    employ the club head speed and the time between light level transitions to determine the distance between points of intersection with perpendicular and angled beams; and    employ the angle and distance between points of intersection to determine the club head height.    
   
   
       6 . The system of  claim 5  further comprising: 
 a retroreflective strip coupled to the golf club head;    a light source configured to emit light toward a location in a path of the swung golf club;    a light receiver configured to receive light reflected from the reflective materials; and    the controller further configured to generate at least one signal for each transition in light level reflected from the reflective material attached to the club.    
   
   
       7 . The system of  claim 6  wherein the processor is further configured to: 
 differentiate a signal generated by light reflected from the attached reflective material; and    correlate the differentiated signal to transitions in light levels reflected from the reflective material.    
   
   
       8 . The system of  claim 7  wherein the processor is further configured to: 
 divide the width of the attached reflective material by the time between two transitions in light reflected from the reflective material to obtain the club head speed.    
   
   
       9 . The system of  claim 7  wherein the processor is further configured to: 
 compare the club head speed to a threshold club head speed to determine whether the transitions in light level are associated with an undesirable artifact.    
   
   
       10 . The system of  claim 9  wherein the processor is further configured to: 
 receive reflected light at a plurality of locations; and    divide the distance between two receiving locations by the time between two light transition events to obtain the club head speed.    
   
   
       11 . The system of  claim 10  wherein the processor is further configured to: 
 correlate reflected light signals for a plurality of locations to determine whether the light level transitions are associated with an undesirable artifact.    
   
   
       12 . A method of determining the height of a swung golf club head having retroreflective material coupled to it, comprising the steps of: 
 (A) emitting a light toward as location in a path of the swung golf club;    (H) receiving light reflected from the retroreflective material; and    (I) generating at least one signal in response to the reception of light reflected from the club head,    (J) employing light reflected from a light source that is substantially perpendicular to the flight path of a golf club head and light reflected from a light source that is at an angle between perpendicular and parallel to that of the flight path of a golf club head to determine the height of the swinging golf club head.    (K) determining the time between light level transitions corresponding to the points of intersection of the retroreflective material and light beamed from a transmitter that is oriented substantially perpendicular to the flight path of a golf club head and light level transitions reflected from a light source beamed at a known angle between perpendicular and parallel to that of the flight path of a golf club head;    (L) employing the club head speed and the time between light level transitions to determine the distance between the points of intersection with perpendicular and angled beams; and    (M) employing the angle and distance between points of intersection to determine the club head height;    (N) activating the transmitters at a high power level; and    
   
   
       13 . The method of  claim 12  further comprising the steps of: 
 (O) differentiating a signal generated by light reflected from retroreflective material coupled to the golf club; and    (P) correlating the differential signal to transitions in light levels reflected from the retroreflective material.    
   
   
       14 . The method of  claim 13  wherein the width of the retroreflective material is predetermined and the method further comprises the step of: 
 (Q) dividing the width of the retroreflective material by the time between two transitions in light reflected from the reflected material to obtain the club head speed.    
   
   
       15 . The method of  claim 14  further comprising the step of: 
 (R) comparing the club head speed to a threshold club head speed to determine whether the transitions in light level are associated with club head movement of interest or the transitions are associated with an undesirable artifact.    
   
   
       16 . The method of  claim 15  further comprising the steps of: 
 (S) receiving reflected light at a plurality of locations; and    (T) dividing the distance between two receiving locations by the time between two light transition events to obtain the club head speed.    
   
   
       17 . The method of  claim 16  further comprising the step of: 
 (U) correlating reflected light signals for a plurality of locations to determine whether the light level transitions are associated with club head movement of interest or the transitions are associated with an undesirable artifact.    
   
   
       18 . The method of  claim 17  further comprising the steps of: 
 (V) employing a plurality of transmitters and receivers along the expected golf club head flight path; and    (W) using one or more of the receivers as a trigger for other transmitters and receivers, whereby the activation of a trigger receiver by reflected light activates non-trigger transmitters and receivers.    
   
   
       19 . The method of  claim 17  further comprising the step of: 
 (X) computing a club swing path angle.    
   
   
       20 . The method of  claim 17  further comprising the step of: 
 (Y) computing a club head angle.    
   
   
       21 . The method of  claim 17  further comprising the step of: 
 (Z) computing a club head lateral alignment.    
   
   
       22 . The method of  claim 17  further comprising the step of: 
 (AA) computing an effective club head speed.