| This paper discusses the inertia tensors of tennis rackets and
their influence on the elbow swing torques in a forehand motion, the
loadings transmitted to the elbow from central and eccentric impacts,
and the racket acceleration responses from central and eccentric impacts.
Inertia tensors of various rackets with similar mass and mass center
location were determined by an inertia pendulum and were found to
vary considerably in all three orthogonal directions. Tennis swing
mechanics and impact analyses were performed using a computer model
comprised of a full-body model of a human, a parametric model of the
racket, and an impact function. The swing mechanics analysis of a
forehand motion determined that inertia values had a moderate linear
effect on the pronation-supination elbow torques required to twist
the racket, and a minor effect on the flexion-extension and valgus-varus
torques. The impact analysis found that mass center inertia values
had a considerable effect on the transmitted torques for both longitudinal
and latitudinal eccentric impacts and significantly affected all elbow
torque components. Racket acceleration responses to central and eccentric
impacts were measured experimentally and found to be notably sensitive
to impact location and mass center inertia values.
KEY
WORDS: Biomechanical models, tennis swing, forehand, elbow loads,
impact behavior.
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