The purpose of this study is to investigate the impact effect of varied structure of golf ball. The researcher applied finite element analysis software LS-DYNA to do nonlinear impact analysis of different golf ball models. It was hoped that this study could design a better golf ball for golfer. The researcher had developed ten stress versus strain curves of two-piece golf balls (including a core and a cover) and three-piece golf balls (including a core, an inner cover and a cover) and four different thicknesses of inner cover of three-piece golf balls. The simulation also adjust the density of inner cover to analyze the impact procedure under the definite weight. With the special design of two-piece balls and three-piece balls, the impact models extract the ball velocities, and angular velocities for the calculation of the ball flight. Finally, the researcher made suggestions for some combination of material property and thickness of the core and the inner cover of the golf ball for the designer to develop a suitable golf ball.

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Abstract Introduction: Ball trajectory in the golf swing is an important outcome variable for golf performance, however, no direct investigation of ball flight trajectory variability for pre-elite players has been conducted. Purpose: The purpose of this study was to examine correlations between average score and ball trajectory variability (for carry and lateral displacement) on pre-elite golfers both at and between two different clubs.  Methods: Sixteen pre-elite/elite golfers were included in the study, 11 men and 5 women with a mean age of 22 ±2 (SD). An actual average (mean) score was calculated for each player’s first ten competition rounds. Subjects were then instructed to hit 5 balls, with focus on consistency, with their seven iron and then hit 5 balls approximately 70 metres with their preferred wedge. Ball trajectory variables were recorded using a Flightscope® Kudo Doppler radar launch monitor system (EDH South Africa (PTY) Ltd). Statistical calculation of averages, standard deviation (SD), normalised root-mean, coefficient of variance, performance error index (PEI= and Pearson’s correlation. Results: The results from the present study showed there was no significant correlation between average score (76.2 ±1.9) and variability of ball trajectory, for the seven iron or wedge. Results also showed average seven iron CV for carry and lateral PEIdisplacement was 5% and 3% respectively, whilst average wedge carry CV for carry and lateral PEIdisplacement was 9% and 2% respectively.  Carry CV and Lateral CV PEI were moderately correlated (r=0.61, p=0.012) with each other for the wedge. Conclusion: : Our findings show no correlation between shot variability and golf score, however we found weak correlation between carry and lateral variability for the wedge. In order for effective coaching more understanding into the importance of biomechanical variability and golf performance is required, further research is needed to better understand the implication of our findings

abstract: The flow around a golf ball is studied using direct numerical simulation (DNS). An immersed boundary approach is adopted in which the incompressible Navier-Stokes equations are solved using a fractional step method on a structured, staggered grid in cylindrical coordinates. The boundary conditions on the surface are imposed using momentum forcing in the vicinity of the boundary. The flow solver is parallelized using a domain decomposition strategy and message passing interface (MPI), and exhibits linear scaling on as many as 500 processors. A laminar flow case is presented to verify the formal accuracy of the method. The immersed boundary approach is validated by comparison with computations of the flow over a smooth sphere. Simulations are performed at Reynolds numbers of 2.5 × 104 and 1.1 × 105 based on the diameter of the ball and the freestream speed and using grids comprised of more than 1.14 × 109 points. Flow visualizations reveal the location of separation, as well as the delay of complete detachment. Predictions of the aerodynamic forces at both Reynolds numbers are in reasonable agreement with measurements. Energy spectra of the velocity quantify the dominant frequencies of the flow near separation and in the wake. Time-averaged statistics reveal characteristic physical patterns in the flow as well as local trends within dimples. A mechanism of drag reduction due to the dimples is confirmed, and metrics for dimple optimization are proposed. / Dissertation/Thesis / Ph.D. Mechanical Engineering 2011

This work deals with the golf ball flight simulation based on video recordings. The way how to determine the trajectory of a golf ball using several initial points is described here. For the ball recognition there are used computer vision techniques, particulary pattern recognition. The work covers physics of the golf ball, it deals with physical influences that occurs during the ball flight and it tries to describe the trajectory approximation.

The main aim of this master's thesis is create golf ball picker with charging station. These two components create the system, which automates process of golf ball collection on driving range. The robot replaces human manual activity in this branch and it eliminates injury. On the other hand, robot respects functional, psychological, ecological and aesthetic demands. It demarcates standard principles of these days and new way how to collect balls on driving range.

This thesis deals with reconstruction of golf ball position using multiple cameras. Reconstruction will be used for golf simulator project. System is using fotogrametric calibration and triangulation algorithm for obtaing point coordinates. Work also discuss options for camera selection. The result is making of prototype of the simulator.