A Three-Dimensional Forward Dynamic Model of the Golf Swing

Abstract

A three-dimensional (3D) predictive golfer model can be a valuable tool for investigating the golf swing and designing new clubs. A forward dynamic model for simulating golfer drives is presented, which includes: (1) a four degree of freedom golfer model, (2) a flexible shaft model based on Rayleigh beam theory, (3) an impulse-momentum impact model, (4) and a spin rate controlled ball trajectory model. The input torques for the golfer model are provided by parameterized joint torque generators that have been designed to mimic muscular inputs. These joint torques are optimized to produce the longest ball carry distance for a given set of golf club design parameters. The flexible shaft model allows for continuous bending in the transverse directions, axial twisting of the club and variable shaft stiffness along its length. The completed four-part model is used for examining the following parameters of interest in club design by performing simulation experiments: clubhead mass, clubhead centre of mass location, clubhead moment of inertia, shaft flexibility, and clubhead and shaft aerodynamics.

Analysis of the experiments led to the following recommendations for golf club design: 1. The clubhead mass should continue to be around 200g. 2. The centre of mass of the clubhead should be as close to the face as possible. 3. Shaft flexibility should be tuned for an individual golfer, depending on their particular swing. 4. Clubhead and shaft aerodynamic drag have a significant effect on the ball carry and clubhead orientation, and should be minimized during the club design process.

Finally, suggestions are made for future research which can be performed in this area.