One camera stereo system

• US 8,872,914 B2
• Filed: 02/04/2004
• Issued: 10/28/2014
• Est. Priority Date: 02/04/2004
• Status: Active Grant

• Current Assignee: Acushnet Company (FILA Holdings Corp.)
• Original Assignee: Acushnet Company (FILA Holdings Corp.)
• Inventors: Gobush, William
• Primary Examiner(s): WONG, ALLEN C
• Application Number:
  US10/770,457
• Publication Number:
  US 20050168578A1
• Time in Patent Office: 3,919 Days
• Field of Search: 348/42, 348/135, 349/11, 382/284, 396/351, 250/206.1, 700/91, 356/601
• US Class Current: 348/135
• CPC Class Codes: A63B 2024/0034 during flight
• CPC Class Codes: A63B 2243/007 American football
• CPC Class Codes: A63B 24/0021 Tracking a path or terminating locations
• CPC Class Codes: A63B 69/0002 for baseball
• 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 69/38 for tennis A63B61/006, A63B69/0073 and A63B69/0097 take precedence
• CPC Class Codes: H04N 13/218 using spatial multiplexing

Abstract

A one camera system that measures golf club and golf ball kinematics is disclosed. Preferably, a plurality of retroreflective or fluorescent markers are placed on the surface of a golf ball. Using a single strobe lamps, images of a golf ball at two points in motion are acquired. The output of each of the strobe lamps is preferably filtered to pass predetermined colors of light. The input to each of the cameras is also preferably filtered. The output from the strobe lamp passes through at least one of a beam splitting mirror and reflective front surface mirror. Based on the filtered light outputs generated by the strobe lamp and the filtered camera input, at least two images of the golf ball, taken from two different angles, may be acquired. The acquired images may be used to analyze the kinematics of the golf ball.

Claims

1. A camera system for monitoring the movement of golf equipment through a field of view, comprising:

a single camera comprising an imaging sensor operable to simultaneously acquire two perspective views of an object at a first location along a trajectory within the field of view of the camera and simultaneously acquire two perspective views of the object at a second location along a trajectory within the field of view;

wherein the two perspective views of a single field of view are based on at least two surfaces, wherein one of the surfaces is semi-transmissive and the other surface is substantially reflective.

2. The camera system according to claim 1, wherein one of the surfaces is a front surface mirror.

3. The camera system according to claim 1, wherein the camera is positioned such that the camera forms an angle of 5 degrees or less with respect to the field of view.

4. The camera system according to claim 1, wherein the camera is positioned such that the camera forms an angle of 90 degrees or less with respect to the field of view.

5. The camera system according to claim 1, wherein the camera is positioned such that the camera forms an angle of 180 degrees or less with respect to the field of view.

6. The camera system according to claim 1, wherein an angle between the two different perspectives from an optical axis to the scene of interest is preferably about 2 degrees or less.

7. The camera system according to claim 1, wherein an angle between the two different perspectives from an optical axis to the scene of interest is preferably about 5 degrees or less.

8. The camera system according to claim 1, wherein an angle between the two different perspectives from an optical axis to the scene of interest is preferably about 10 degrees or less.

9. The camera system according to claim 1, wherein the two perspectives overlap by about 50% or less.

10. The camera system according to claim 1, wherein the two perspectives overlap by about 70% or less.

11. The camera system according to claim 1, wherein the two perspectives overlap by about 90% or less.

12. The camera system according to claim 1, wherein the ratio of transmission to reflection is 5:

5.

13. The camera system according to claim 1, wherein the ratio of transmission to reflection is 6:

4.

14. The camera system according to claim 1, wherein the ratio of transmission to reflection is 7:

3.

15. The camera system according to claim 1, wherein the ratio of transmission to reflection is 3:

7.

16. The camera system according to claim 1, wherein the ratio of transmission to reflection is 4:

6.

17. The camera system according to claim 1, wherein the resolution of said camera is about 100 or greater pixels/inch.

18. The camera system according to claim 1, wherein the size of the single field of view is about 12 square inches or greater.

19. The camera system according to claim 1, wherein the size of the single field of view is about 36 square inches or greater.

20. The camera system according to claim 1, wherein the size of the single field of view is about 100 square inches or greater.

21. The camera system according to claim 1, wherein one or more objects are selectively positioned within the single field of view, and wherein said objects comprise at least one of a golf club and a golf ball.

22. The camera system according to claim 1, wherein the camera is a multishutter camera.

23. The camera system according to claim 1, wherein the camera is operable to acquire multiple frames.

24. The camera system according to claim 1, wherein the camera is operable to acquire multiple images on a single frame.

25. A camera system, comprising:

a single camera having an imaging sensor;

a mirror; and

a beamsplitter comprising a mirror configured and dimensioned for transmission and reflection;

wherein said mirror and said beamsplitter are configured to provide two perspective views of an object at a first location along a trajectory within a field of view of the camera and two perspective views of the object at a second location along a trajectory within the field of view of the camera.

26. The camera system according to claim 25, wherein the camera does not face the field of view.

27. The camera system according to claim 25, wherein the resolution of said camera is about 200 or greater pixels/inch.

28. The camera system according to claim 25, wherein the ratio of transmission to reflection of the beamsplitter is about 5:

5.

29. The camera system according to claim 25, wherein the size of the field of view is about 36 square inches or greater.

30. The system of claim 25, further comprising a moving object, wherein the minor and the beamsplitter are configured and dimensioned to obtain a first and second image of the moving object at a first position within the field of view and a third and fourth image of the moving object at a second position within the field of view.

31. An apparatus for analyzing the kinematics of an object, comprising:

a camera positioned to permit the camera to capture two different perspective views of an object at a first location along a trajectory within a field of view of the camera simultaneously and two different perspective views of the object at a second location along a trajectory within the field of view of the camera;

at least one golf ball or club having a plurality of markers; and

a beam splitting mirror and a front surface mirror, each of said mirrors positioned to direct light from a strobe lamp onto the field of view;

wherein the beam splitting minor transmits about 50% of light that strikes the beam splitting mirror'"'"'s surface.

32. The apparatus according to claim 31, wherein said markers include retroreflective markers responsive to on-axis lighting.

33. The apparatus according to claim 31, wherein said markers include fluorescent markers responsive to light within a predetermined wavelength.

34. The apparatus according to claim 31, wherein said camera includes a CCD.

35. A method for analyzing the kinematics of an object, comprising:

acquiring two perspective views of an object at a first location along a trajectory within a field of view and two perspective views of an object at a second location along a trajectory within the field of view based on a single camera having an imaging sensor, wherein the acquiring comprises using a beamsplitter comprising a mirror configured and dimensioned for transmission and reflection.

36. The method according to claim 35, wherein said acquiring comprises using two reflective surfaces to direct light towards the field of view.

37. The method according to claim 35, wherein said acquiring further comprises using two reflective surfaces to direct light from the field of view towards the single camera.