Abstract:
The invention is a motion training method. The motion of golf swing will be emphasized. In order to guide a golfer through a proper swing, his/her swing must be analyzed first. To analyze the swing, a set of frame photos will be needed. 
     From those frame photos, the invented method will provide a rule based method to calculate the body mechanics/forces of the golfer. Once the body mechanics/forces are known, the system will then determine the swing is correct or incorrect. If the swing is incorrect, the system will then make suggestions to the golfer about how to correct his/her swing.

Description:
RELATED APPLICATIONS 
       [0001]    This application is a divisional of co-pending U.S. patent application Ser. No. 11/472,891, entitled “Rule Based Body Mechanics Calculation,” filed Jun. 22, 2006 by the same inventor (now U.S. Pat. No. 7,404,774), which is incorporated by reference herein in its entirety. 
     
    
     BACKGROUND 
     1. Background Art 
       [0002]    1. U.S. Pat. No. 5,333,061, Nakashima, et al. Method and apparatus for producing an instructional video analyzing a golf swing. 
         [0003]    2. U.S. Pat. No. 5,823,878, Welch, Golf swing analysis apparatus and method. 
         [0004]    3. U.S. Pat. No. 6,793,585, Miyamoto, et al. Swing measurement method, golf swing analysis method, and computer program product. 
         [0005]    4. United States Patent Application, 20040147330, DiMare, Mark, Swing fault-correction matrix. 
       2. Other References 
       [0006]    [1]. The Everything Golf Instruction Book by Rob Blumer and Dr. Rex Chaney, Adams, 2003. 
         [0007]    [2]. The Golf Doctor by Edward Craig, Hamlyn, 2004. 
       SUMMARY 
       [0008]    This invention is related to a motion training/reforming method. Using a video camera to record an action and later reviewing each frame to analyze the movement, is a common practice in many sports. For instance video a golfer&#39;s swing and analyze it later. This has already been done for many years. In fact many patents have already been issued for methods which analyze golf swing by using video photos (see Background Art (1), (2) and (3) above). 
         [0009]    U.S. Pat. No. 5,823,878 discloses a certain method of analyzing a golf swing by using video photos. The foundation of this method is completely based on motion capturing technology. A set of 3D -points on the golfer&#39;s body and club is captured. The (x, y, z)-coordinates of those 3D -points are calculated from at least two sets of photos taking at different angles. Then the body mechanics of the golfer are calculated by processing those captured 3D points with certain general processors. 
         [0010]    Any motion, in general, is dominated by certain physical laws/rules. For example, a golf swing is dominated by the following two physical rules (see Other Reference [1] above), i.e. during the swing, 
         [0011]    (1) the golfer&#39;s upper body rotates around his/her backbone and 
         [0012]    (2) the backbone is almost constantly pointing at a fixed direction. 
         [0013]    However, these physical rules are completely ignored by U.S. Pat. No. 5,823,878. If those rules can be used in the calculation of the body mechanics, all the complicated system and processes such as motion capturing mentioned in U.S. Pat. No. 5,823,878 will become unnecessary. 
         [0014]    Starting with a set of frame photos, this invented method will use a set of physical rules (including those mentioned above) and a set of 2D lines to calculate the body mechanics/forces of the golfer. Once the body mechanics/forces are known, we will have the essential information of the golfer&#39;s swing. This essential information will then provide the golfer with a clue of how to correct his/her movement. 
         [0015]    Although the motion of golf swing is emphasized, the application of this invented method will not be limited to the golf swing. 
         [0016]    Although this invented method can be applied to different kinds of motions, in order to make things clear we will concentrate our motion just on golf swing. A good golf swing is composed of correct body, hip, arm and club movements. The object of this invented training method is to help train a golfer to move his/her body, hip, arm and club correctly. 
         [0017]    Using photos to help train a golfer is nothing new. However, this inventive method will take a new approach. A set of consecutive photos will be used as the input. A set of 2D lines on the player&#39;s body will be selected from the photos. The selected lines can either be the backbones (see  FIG. 1 ), shoulder lines (see  FIG. 2 ), waist lines or any other meaningful lines. The player&#39;s body mechanics will then be calculated from the motion of these selected lines. To make the calculation simple, a set of physical rules which dominates the motion of the swing, will be used. The advantages of adapting physical rules are: 
         [0018]    (1) The 3D technology such as motion capturing used in calculating body mechanics (see background patent (2)) becomes unnecessary. 
         [0019]    (2) The 3D -points construction which is needed in the classic method (see background patent (2)) will be either unnecessary or greatly reduced. 
         [0020]    Once the body mechanics/forces are known, the system will then be able to determine whether the swing is correct or incorrect. If the swing is incorrect, the system will then make suggestions to the golfer about how to correct his/her swing. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0021]      FIG. 1  contains a set of frame photos of a golf swing; 
           [0022]      FIG. 2  is an illustration of how to obtain the (x, y, z)-coordinates of a golfer&#39;s backbone; 
           [0023]      FIG. 3  shows how to calculate the rotating angle of the upper body; 
           [0024]      FIG. 4  displays the acceleration diagrams of the upper body; 
           [0025]      FIG. 5  is an illustration of how to construct the waist lines; 
           [0026]      FIG. 6  is an illustration of how to obtain the (x, y, z)-coordinates of the plane normal of a swing plane; 
           [0027]      FIG. 7  shows how to calculate the rotating angle of the club; 
           [0028]      FIG. 8  displays the acceleration diagrams of the club; 
           [0029]      FIG. 9  is an illustration of how to construct the hand and arm lines; and 
           [0030]      FIG. 10  is a data flow diagram of the system. 
       
    
    
     DETAILED DESCRIPTION  
     (RULES-A) 
       [0031]    During a golf swing, the golfer&#39;s body will: 
         [0032]    (1) rotate around his/her backbone and 
         [0033]    (2) the backbone is almost constantly pointing at a fixed direction (see [1]). 
         [0000]    The above physical rules dictate the motion of the golfer&#39;s upper body. Deduced from these rules, to obtain a golfer&#39;s upper body mechanics, we only need to calculate: 
         [0034]    (1) the backbone positions of the golfer and 
         [0035]    (2) the rotation angles of the body around the backbone. 
         [0036]    How to calculate the backbone positions of the player  100  is shown in  FIG. 1  and  FIG. 2 .  FIG. 1  contains a sequence of golf swing frame pictures 
         [0037]    (F 1 , F 2 , F 3 , F 4 , F 5 ). 
         [0000]    Two fixed locations M 1  and M 2  are marked on the golfer&#39;s backbone and are connected with a line (see  FIG. 1 ). The same process is repeated for all the frames. We will then have a set of lines 
         [0038]    (B 1 , B 2 , B 3 , . . . ). 
         [0000]    Note that for the reason of simplicity M 1  and M 2  are not drawn on all the frames. 
         [0039]    Once we have the geometry of (B 1 , B 2  . . . B 5 ), the next step is to get the (x, y, z)-coordinates of (B 1 , B 2  . . . B 5 ). To get the (x, y, z)-coordinates we need both the front and side views.  201  and  203  of  FIG. 2  shows the (x, y) components of B  1 .  202  and  204  of  FIG. 2  shows the (y, z) components of B 1 . Add the z-component of (y, z) to (x, y) and we will have the (x, y, z)-coordinates of B 1 . Repeat the same process for all the frames and we will have all the (x, y, z)-coordinates of B 1 , B 2  . . . B 5 . 
         [0040]    With the backbone positions defined, we can now calculate the upper body rotation angles around the backbone. In  301  of  FIG. 3  for each frame photo we select two fixed locations M 3  and M 4  on the shoulder. Connect M 3  and M 4  with a line. Repeat the same process for all the frames. We will then have a set of lines: 
         [0041]    (S 1 , S 2  . . . S 5 ). 
         [0000]    Let A 1  be the upper body rotating angle of the first frame. Note that to calculate A 1 , is equivalent to calculate the rotating angle which rotates line S 1  to S 2  around the backbone B 1  (see  302  of  FIG. 3 ). Also note that the calculation of A 1  is straight forward. There is no need to calculate the z-component of S 1  and S 2 . We only need to treat the z-component of S 1  as zero and ignore the z-component of S 2 . Repeat the same process for all the frames. We will then have all the angles 
         [0042]    (A 1 , A 2  . . . A 5 ). 
         [0043]    In  FIG. 4 , we redraw all the backbones Bi (i= 1 ,  2  . . .  5 ) by giving ( 1 ) equal distance on x-direction and ( 2 ) the length of Bi equals Ai. The diagram we obtained is called the body acceleration diagram DIAG-BODY  402  ( FIG. 4 ) and it represents the upper body mechanics of the golfer. The upper body acceleration diagram can be used to determine if the golfer moves his/her upper body correctly. The determination is done by comparing the diagram generated by the golfer with a correct one stored in database. See DIAG-BODYD  401  ( FIG. 4 ). 
         [0044]    The diagram stored in database is either known as the expert knowledge or predefined conditions. 
         [0045]      401  of  FIG. 4  is a correct acceleration diagram stored in database and  402  is an incorrect acceleration diagram generated by the golfer. From the comparison of these two diagrams, the system can obviously make a suggestion to the player that he/she needs to rotate his/her upper body more during the down swing. 
         [0046]    Same as the upper body, the hip mechanics of a golf swing (i.e. the angle that the hip rotates around the backbone) can also be calculated in the same way. The only difference is that to calculate the angles we use the waist lines 
         [0047]    (W 1 , W 2  . . . W 5 ) 
         [0000]    Instead of the shoulder lines (S 1 , S 2  . . . S 5 ). 
         [0048]      FIG. 5  shows how to construct the waist lines. Select two fixed locations M 1  and M 2  on the waist, and then connect M 1  and M 2  with a line W 1 . Note that only W 1  is drawn in  FIG. 5 . For the simplicity of drawing, W 2 , W 3  . . . W 5  are not shown. (RULES-B) 
         [0049]    (a) During a golf swing, the club head stays in a plane and this plane is known as the swing plane ([ 1 ]). 
         [0050]    (b) The golfer&#39;s hand (or arm) will also stay in a slightly different plane. 
         [0000]    In  601  of  FIG. 6  PL is the swing plane of the club head and PN is the plane normal of PL. The (x, y z)-coordinates of PN are shown in  601  and  602  of  FIG. 6 . In  701  of  FIG. 7 , two fixed points M 1  and M 2  are selected on the club. Connect M 1  and M 2  we will have a line. Repeat the same process and we will have a set of lines 
         [0051]    (C 1 , C 2  . . . C 5 ). 
         [0000]    Note that for simplicity only C 1  and C 2  are drawn. 
         [0052]    In  702  of  FIG. 7 , we define the angle AN 1  as the rotating angle from C 1  to C 2  around the plane normal PN. Similar to the calculation of the said body angle A 1 , the calculation of AN 1  is also straight forward. Repeat the same calculation and we will have all the club angles 
         [0053]    (AN 1 , AN 2  . . . AN 5 ). 
         [0054]    In  FIG. 8  we construct a diagram by giving the y-values at xi equals ANi, where i= 1 ,  2  . . .  5 . The diagram we obtained here is called the club acceleration diagram DIAG-CHA  802 , shown in  FIG. 8 . 
         [0055]    Similar to body acceleration, the club acceleration diagram can also be used to determine if the golfer moves his/her club correctly. The determination is done by comparing the diagram generated by the golfer with a correct one stored in database. See diagram DIAG-CHAD  801  ( FIG. 8 ). 
         [0056]    The diagram stored in database is either known as the expert knowledge or predefined conditions. 
         [0057]      FIG. 8  shows a correct acceleration diagram DIAG-CHAD  801  stored in database and an incorrect acceleration diagram DIAG-CHA  802  generated by the golfer. From the comparison of these two diagrams, once again the system can obviously make suggestion to the player that he/she needs to accelerate the club more during the down swing. 
         [0058]    The hand (or arm) mechanics can also be calculated in the same way as the club rotation. The only differences are: 
         [0059]    (a) hand (or arm) rotates around a slightly different plane PL′. The plane normal PN′ of PL′ is very close to PN. The (x, y, z)-coordinates of PN′ can also be obtained in the same way as PN. 
         [0060]    (b) we use hand lines 
         [0061]    (H 1 , H 2  . . . H 5 ) or arm lines 
         [0062]    (AM 1 , AM 2  . . . AM 5 ) 
         [0063]    Instead of club lines (C 1 , C 2  . . . C 5 ). 
         [0064]      FIG. 9  shows how to construct lines (H 1 , H 2  . . . H 5 ) and (AM 1 , AM 2  . . . AM 5 ). Three fixed locations M 1 , M 2  and M 3  are selected. Line H 1  is constructed by connecting M 1  and M 2  and the line AM 1  is constructed by connecting M 1  and M 3 . Note that only H 1  and AM 1  are drawn in  FIG. 9 . For simplicity, the rest of lines are not drawn. 
         [0065]    Similarly, once the hand (or arm) mechanics are calculated, we can also construct the hand (or arm) acceleration diagram DIAG-CHA  802  ( FIG. 8 ). Furthermore the system can then make suggestion to the player by comparing the diagram generated by the golfer with the one stored in database. See DIAG-CHAD  801  ( FIG. 8 ). 
         [0066]    Once again the diagram stored in database is either known as the expert knowledge or predefined conditions. 
         [0067]      FIG. 10  shows the data flow of the system. Video photos  1001  are the input to the system. Physical rules  1002  are used for calculation. The body mechanics are calculated in  1003 . The results of  1003  are passed to  1004  for swing analysis. The results of  1004  are used by  1005  to give advices to the golfer. 
         [0068]    Note that in calculating the body mechanics of a golf swing, rules RULES-A and RULES-B are used as the foundation of the calculation. For other sports such as baseball or tennis the player&#39;s body mechanics will satisfy a different set of physical rules. To calculate the body mechanics, these different rules should be used.