Method and apparatus to determine golf ball trajectory and flight

• US 6,488,591 B1
• Filed: 05/08/2000
• Issued: 12/03/2002
• Est. Priority Date: 09/18/1998
• Status: Expired due to Term

• Current Assignee: Acushnet Company (FILA Holdings Corp.)
• Original Assignee: Acushnet Company (FILA Holdings Corp.)
• Inventors: Aoyama, Steven, Hebert, Edmund A., Winfield, Douglas C., Gobush, William, Days, Charles, Silveira, James Alan, Pelletier, Diane
• Primary Examiner(s): SAGER, MARK ALAN
• Application Number:
  US09/566,803
• Time in Patent Office: 939 Days
• Field of Search: 473/131, 473/140-141, 473/198-200, 473/219-226, 473/351, 473/353, 473/409, 382/106, 382/107, 382/162, 382/164-165, 358/538, 358/537, 700/91, 434/247-249, 434/251, 434/252, 348/552, 348/61, 348/143, 348/169, 348/207.99, 348/207.1, 348/207.11, 348/208.14
• US Class Current: 473/199
• CPC Class Codes: A63B 2024/0028 Tracking the path of an object, e.g. a ball inside a soccer pitch
• CPC Class Codes: A63B 2024/0031 at the starting point
• CPC Class Codes: A63B 2024/0034 during flight
• CPC Class Codes: A63B 2102/32 Golf
• CPC Class Codes: A63B 2220/05 Image processing for measuring physical parameters
• CPC Class Codes: A63B 2220/16 Angular positions
• CPC Class Codes: A63B 2220/20 Distances or displacements
• CPC Class Codes: A63B 2220/30 Speed
• CPC Class Codes: A63B 2220/35 Spin
• CPC Class Codes: A63B 2220/70 Measuring or simulating ambient conditions, e.g. weather, terrain or surface conditions
• CPC Class Codes: A63B 2220/805 Optical or opto-electronic sensors
• CPC Class Codes: A63B 2220/806 Video cameras
• CPC Class Codes: A63B 2220/807 Photo cameras
• CPC Class Codes: A63B 2220/808 Microphones
• CPC Class Codes: A63B 2220/89 Field sensors, e.g. radar systems
• CPC Class Codes: A63B 2225/02 Testing, calibrating or measuring of equipment
• CPC Class Codes: A63B 2225/74 with powered illuminating means, e.g. lights
• CPC Class Codes: A63B 24/0003 Analysing the course of a movement or motion sequences during an exercise or trainings sequence, e.g. swing for golf or tennis
• CPC Class Codes: A63B 24/0021 Tracking a path or terminating locations
• CPC Class Codes: A63B 43/008 with means for improving visibility, e.g. special markings or colours illuminating or reflecting means A63B43/06
• CPC Class Codes: A63B 43/06 : with illuminating devices ; with reflective surfaces
• CPC Class Codes: A63B 69/3614 : using electro-magnetic, magnetic or ultrasonic radiation emitted, reflected or interrupted by the golf club
• CPC Class Codes: A63B 69/3658 : Means associated with the ball for indicating or measuring, e.g. speed, direction
• CPC Class Codes: A63B 71/06 : Indicating or scoring devices for games or players , or for other sports activities
• CPC Class Codes: G01S 11/12 : using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 17/18 : wherein range gates are used
• CPC Class Codes: G01S 17/50 : Systems of measurement based on relative movement of target
• CPC Class Codes: G01S 17/66 : Tracking systems using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 17/89 : for mapping or imaging

Abstract

A launch monitor system including a support structure, a first light-reflecting element disposed on this support structure, a lighting unit and an camera unit. A computer receives signals generated by light patterns received by the camera unit and computes a variety of flight characteristics for the object. The system may be moved back and forth to vary the field-of-view of the camera unit. The system also computes and displays object trajectories from the computed flight characteristics which account for the characteristics of the object and the atmospheric conditions.

Claims

1. A method of reducing extraneous areas of brightness in an image of a spinning sphere having contrasting elements, comprising the steps of:

segmenting the image into a respective number of areas of brightness;

calculating the center of each of the areas of brightness;

determining the principle axes of the areas of brightness;

calculating a ratio of the principle axes of each area of brightness;

eliminating the area of brightness if the ratio of the principle axes exceeds a predetermined value.

2. The method of claim 1, wherein the step of calculating the center of each of the areas of brightness includes performing a plurality of summations for the areas of brightness and calculating net moments about two axes.

3. The method of claim 1, wherein the segmenting step is preceded by setting a brightness threshold level in the image to a predetermined level.

4. The method of claim 1, wherein the center calculating step is preceded by eliminating areas of brightness in the image that have an area different from a predetermined area.

5. The method of claim 4, wherein the predetermined area is about 105 pixels.

6. A method of filtering an image of a moving object having reflective markers comprising the steps of:

displaying portions of the image which have a brightness above a predetermined threshold level in a first color;

displaying portions of the image which have a brightness below the threshold level in a second color;

segmenting the first color portions into areas of brightness;

eliminating areas of brightness in the image that have an area outside a predetermined range; and

eliminating areas of brightness in the image that have an aspect ratio greater than a predetermined value.

7. The method of claim 6, wherein the predetermined value is 4.

8. The method of claim 6, wherein the predetermined value is 5.

9. A method of processing images of a moving object having reflective markers comprising the steps of:

capturing at least one bright image of the object;

dividing the image into a plurality of pixels;

assigning a color to each pixel, the assigned color being either a first color if the pixel has a brightness above a predetermined threshold level or another color if the pixel has a brightness below the predetermined threshold level;

connecting adjacent pixels of the first color to form bright areas;

corresponding the bright areas to the markers on the object; and

calculating the location of the markers from the at least one image.

10. The method of claim 9, wherein the capturing step further comprises the steps of:

capturing a first pair of images on a first image frame of a first camera; and

capturing a second pair of images on a second image frame of a second camera.

11. The method of claim 9, wherein the calculating step further comprises the step of mathematically comparing the first pair of images with the second pair of images.

12. The method of claim 9, wherein the corresponding step further comprises the step of eliminating extraneous areas of brightness from the image.

13. The method of claim 9, further comprising determining at least one of the transverse velocity and spin rate of the object.

14. The method of claim 9, wherein the dividing includes dividing the image into rows and columns of pixels.

15. The method of claim 14, wherein the dividing further includes dividing the image into 753 pixels by 244 pixels.

16. The method of claim 9, further comprising:

determining if any of the bright areas are aberrant bright areas that do not correspond to one of the markers; and

ignoring the aberrant bright areas.

17. The method of claim 16, wherein the determining includes determining whether any of the bright areas have an area outside a predetermined range of areas.