Transcript Is golf swing planar or not?

Young-Hoo Kwon, Ph.D.
Biomechanics Laboratory
Texas Woman’s University, Denton, TX
6th World Scientific Congress of Golf, Phoenix, AZ
Accuracy & consistency:
• Distance
• Direction
Planar Motion?
• Planar motion = the simplest shape of motion
• Simple motion  more accurate & consistent
swing
Impact Conditions:
• Motion of the clubhead (velocity)
• Orientation of the clubface
• Location of impact on the clubface
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Swing Plane:
• A frequently used but misleading concept
Controversies:
• Different definitions
• Single vs. multi-plane
• Swing planarity
Mechanical Meaningfulness:
• Plane of motion of the club
• Directly related to the impact conditions
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All phases include BI.
TB
MF
ED
New Approach:
MD
(Kwon et al., 2012)
• Clubhead motion-centric
• Portion of the downswing
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TB-MF
ED-MF
MD-MF
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Actual Trajectory
Projected
Trajectory
Instantaneous
Rotation
Center
Rotation
Arm
Slope
Direction Angle
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Planar
Semi-Planar
Spiral
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Double-Pendulum
Triple-Pendulum
Backswing
Plane
(Hogan & Wind, 1957; Cochran & Stobbs, 1968)
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Motion Planes of the Arm/Shoulder Points
L shoulder Plane
L hand Plane
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Right
Shoulder
Left
Shoulder
Right
Elbow
Left
Hand
10
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One-Plane
Swing
(Hardy & Andrisani, 2005)
Two-Plane
Swing
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(Haney & Huggan, 1999)
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TA
LB
TB
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ED
MD
BI
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Shape of Trajectory at BT
Smooth
Sharp
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Sharp Transition near BI
Impact
Impact
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A Bogey Player
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Yes:
• A well-defined FSP could be determined
regardless of the overall shape of the swing.
• FSP can be used in characetrizing a golfer’s
swing.
No:
• Motion planes of the arm points show large offplane motions of the major players of the multipendulum model.
• Validity of the double- & triple-pendulum
models is questionable.
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