The Effect of Deflection of a Golf club shaft During Down swing

摘要

In this paper, dynamic behavior of golf club shafts before impact is analyzed. Firstly, we have established the measuring system of bending stiffness distribution of the shafts. Then we measure bending strain of the shafts on swinging. We model the shaft as a cantilever beam and we calculate deflection of the shaft before impact with data of bending stiffness distribution and data of bending strain. Additionally, we estimate “Kick Point” of golf shafts. We calculate changing curvature of shafts before impact, so that we make clear which part of shafts are bended and changed curvature exceedingly on swinging. We have proposed the share of this changing ratio in each a third of overall shaft and we call it “Dynamic Flexible Ratio”. The results are summarized as follows f (1) It is possible to classify the type of golfers by comparing deflections of the shaft before impact, and to calculate velocity of golf club head and angle at the tip of shaft by deflection. (2) “Dynamic Flexible Ratio” is closely related to angle at the tip of shaft by deflection.