Golf Club Dynamics Studied with the MPV-800 Multipoint Vibrometer
Golf clubs come in a variety of different types. Drivers are designed to generate distance, wedges to lift the ball out of difficult situations, and putters to gently place the ball in the hole. Golf club manufacturers are constantly pushing the technology in all of their clubs to achieve an edge over their competition with new designs that need to be experimentally analyzed and verified. One critical feature of a golf club is how it responds when the club impacts the ball. This response will affect the movement of the ball and the feel in the hands of the golfer. Polytec’s Multipoint Vibrometer (MPV-800) is an instrument that captures dynamic response data simultaneously at up to 48 points using lasers. Vibration can be captured at 48 discrete locations in 1D mode, or up to 16 points for resolving the complete 3D motion. The MPV-800 will measure the response to a single transient event, such as a golf ball impacting the head of a golf club. Some clubs are more forgiving than others, so that exact point of impact can affect its response and a small deviation may change how that club responds; therefore, it is important to strike the club only once and to capture data simultaneously. In our example we measured on the shaft, but this measurement can also be performed easily on the club head. We tested a 9-iron and a putter with the MPV-800 system.
Golf Club Dynamics Studied with the MPV-800 Multipoint Vibrometer
- 1. · www.polytec.com · © Polytec Anthony Brock • Applications Engineer info@polytec.com 949-943-3033 Multipoint Vibrometer: Golf Club Dynamics
- 2. · www.polytec.com · © Polytec Multipoint Vibrometer (MPV-800) October 2017 2 Polytec’s Multipoint Vibrometer (MPV-800) captures dynamic response data simultaneously at up to 48 points. The system used in these experiments is configured for 1D measurements at up to 24 points or full 3D motion response at up to 8 points.
- 3. · www.polytec.com · © Polytec Golf Clubs Golf clubs come in a variety of different types. There are drivers to hit the ball far, wedges to lift the ball out of difficult situations, and putters to gently place the ball in the hole. Golf club manufacturers are constantly pushing the technology in all of their clubs to achieve an edge over their competition with new designs that need to be experimentally analyzed and verified. One critical feature of a golf club is how it responds when the club impacts the ball. This response will affect the movement of the ball and the feel in the hands of the golfer. October 2017 3 9-iron putter
- 4. · www.polytec.com · © Polytec MPV Setup The 9-iron and the putter in the previous slide are suspended from a stand and the response due to an impact on the club is measured with the Polytec MPV-800. Each club is excited with a single impact to its face. The putter setup is shown to the left. October 2017 4
- 5. · www.polytec.com · © Polytec MPV Data (9-iron) 24 measurement points are aligned onto the rear side of the 9-iron golf club. The impact response is measured simultaneously for all points. Measurement locations are the laser dots seen in the image below. October 2017 5
- 6. · www.polytec.com · © Polytec MPV Data (9-iron) The frequency response of the measured data shows the fundamental bending mode as well as higher order modes of the shaft of the golf club. October 2017 6 50 Hz 5.4 Hz 160 Hz 316 Hz 539 Hz 813 Hz
- 7. · www.polytec.com · © Polytec MPV Data (9-iron) This video shows an animation of the impact response in the time domain lasting approximately 1.5 seconds. The head of the golf club is seen rotating at approximately 5.4Hz and higher frequency waves are seen traveling through the shaft. October 2017 7
- 8. · www.polytec.com · © Polytec MPV Data (9-iron) This video animates the first 25 ms of the time domain response. By slowing down the playback and looking at a small section of time, a wave is seen propagating down the shaft after the impact. This wave is at approximately 300-400Hz. October 2017 8
- 9. · www.polytec.com · © Polytec MPV Data (putter) 24 measurement points are aligned onto the rear surface of the putter golf club. The impact response is measured simultaneously for all points. Measurement locations are the laser dots seen in the image below. October 2017 9
- 10. · www.polytec.com · © Polytec MPV Data (putter) The frequency response of the measured data shows the fundamental bending mode as well as higher order modes of the shaft of the golf club. October 2017 10 2.4 Hz 163 Hz 308 Hz 542 Hz
- 11. · www.polytec.com · © Polytec MPV Data (putter) This video shows an animation of the impact response in the time domain lasting approximately 1.5 seconds. The head of the golf club is seen rotating at approximately 2.4Hz and higher frequency waves are seen traveling through the shaft. October 2017 11 Note: Download the presentation to view the video.
- 12. · www.polytec.com · © Polytec MPV Data (putter) By slowing down the playback and looking at a small section of time, a wave is seen propagating down the shaft after the impact. This wave is at approximately 400-600Hz. October 2017 12 Note: Download the presentation to view the video.