Claims
- 1. A method for predicting the coefficient of restitution of a golf club, the method comprising:
attaching a vibration sensor to a face of the golf club; impacting the attached vibration sensor with an excitation device to generate vibrations in the face; transmitting the force of excitation from the excitation device and the vibrations measured by the vibration sensor to an analyzer to generate frequency domain data for the golf club; transforming the frequency domain data for the golf club into a transfer function for the golf club; and inputting a golf ball model for a specific golf ball into the transfer function and an impact speed in order to generate a predicted COR for the golf club at the impact speed with the specific golf ball.
- 2. The method according to claim 1 wherein the impact speed is the club speed.
- 3. The method according to claim 1 wherein the impact speed is the ball speed.
- 4. The method according to claim 1 wherein the vibration sensor is an accelerometer with the capability of transmitting data to the analyzer.
- 5. The method according to claim 1 wherein the excitation device is an impact device with the capability of measuring the force of impact and transmitting the impact force to the analyzer.
- 6. The method according to claim 1 wherein transforming the frequency domain data comprises:
generating a graph of the frequency; analyzing the phase of the motion of the face of the golf club; selecting a frequency band to minimize noise; and calculating the transfer function.
- 7. The method according to claim 6 wherein the frequency band is from 0 Hertz to 10,000 Hertz.
- 8. The method according to claim 6 further comprising inputting an effective mass of the golf club, the effective mass calculated from the graph of the frequency at 0 Hertz.
- 9. The method according to claim 1 wherein a system identification is used to generate the transfer function.
- 10. A system for measuring the coefficient of restitution of a golf club during impact with a golf ball, the system comprising:
a vibration sensor attached to a point on the face of the golf club, the vibration sensor having means for measuring the vibration of the face; means for exciting the face of the golf club in order to vibrate the face, the excitation means having means for measuring the force of excitation with the face; and means for calculating the coefficient of restitution of the golf club from the vibration of the face, the force of excitation with the face from the excitation means, an effective mass of the golf club and a mass of a golf ball.
- 11. The system according to claim 10 wherein the vibration sensor is an accelerometer with the capability of transmitting data to the analyzer.
- 12. The system according to claim 10 wherein the excitation means is a hammer with the capability of measuring the force of impact and transmitting the impact force to the analyzer.
- 13. The system according to claim 10 wherein the calculating means comprises:
means for generating frequency domain data from the vibrations of the face of the golf club; means for generating a graph of the frequency from the frequency domain data; means for analyzing the phase of the motion of the face of the golf club; means for selecting a frequency band to minimize noise; and means for calculating a transfer function.
- 14. The system according to claim 13 further comprising means for calculating the effective mass of the golf club at zero Hertz on the graph of the frequency.
- 15. A method for predicting the coefficient of restitution of a golf club head, the method comprising:
attaching a vibration sensor to a face of the golf club head; impacting the attached vibration sensor with an impact device to generate vibrations in the face; transmitting the force of impact from the impact device and the vibrations measured by the vibration sensor to an analyzer to generate frequency domain data for the golf club head; transforming the frequency domain data for the golf club head into a transfer function for the golf club head; and inputting a golf ball model for a specific golf ball into the transfer function and an impact speed in order to generate a predicted COR for the golf club head at the impact speed with the specific golf ball.
- 16. The method according to claim 15 wherein transforming the frequency domain data comprises:
generating a graph of the frequency; analyzing the phase of the motion of the face of the golf club head; selecting a frequency band to minimize noise; and calculating the transfer function.
- 17. The method according to claim 16 wherein the frequency band is from 0 Hertz to 10,000 Hertz.
- 18. The method according to claim 16 further comprising inputting an effective mass of the golf club head, the effective mass calculated from the graph of the frequency at 0 Hertz.
- 19. A method for predicting the coefficient of restitution of a golf club, the method comprising:
attaching a vibration sensor to a face of the golf club; exciting the attached vibration sensor with an excitation device to generate vibrations in the face; transmitting the force of excitation from the excitation device and the vibrations measured by the vibration sensor to an analyzer to generate time domain data for the golf club; transforming the time domain data for the golf club into a state-space representation of the golf club; and inputting a golf ball model for a specific golf ball into the transfer function and an impact speed in order to generate a predicted COR for the golf club at the specified impact speed with the specific golf ball.
- 20. The method according to claim 19 wherein the golf club is unshafted.
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] The present application is a continuation-in-part application of co-pending patent application No. 09/826544, which was filed on Apr. 4, 2001.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
09826544 |
Apr 2001 |
US |
Child |
09844160 |
Apr 2001 |
US |