Is golf swing planar or not?

Young-Hoo Kwon, Ph.D.Biomechanics LaboratoryTexas Woman’s University, Denton, TX

6th World Scientific Congress of Golf, Phoenix, AZ

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Golf Performance Factors

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

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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MD

Functional Swing Plane

TB

ED

MF

All phases include BI.

New Approach:• Clubhead motion-centric• Portion of the downswing

(Kwon et al., 2012)

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TB-MF ED-MF MD-MF

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Direction Angle

Slope

Actual Trajectory

ProjectedTrajectory

RotationArm

InstantaneousRotationCenter

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FSP & Swing Styles

Planar SpiralSemi-Planar

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Shoulder-Ball Plane

(Hogan & Wind, 1957; Cochran & Stobbs, 1968)

BackswingPlane

Double-Pendulum Triple-Pendulum

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L shoulder Plane

L hand Plane

Motion Planes of the Arm/Shoulder Points

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LeftShoulder

LeftHand

RightElbow

RightShoulder

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One-PlaneSwing

Two-PlaneSwing

(Hardy & Andrisani, 2005)

One-Plane vs. Two-Plane

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14(Haney & Huggan, 1999)

On-Plane

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TA LB TB

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ED MD BI

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Rotation Center & Arm

Shape of Trajectory at BT

Smooth

Sharp

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ImpactImpact

Sharp Transition near BI

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A Bogey Player

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Is Golf Swing Planar?

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 off-plane motions of the major players of the multi-pendulum model.

• Validity of the double- & triple-pendulum models is questionable.

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Thank you for

your attention!