Department of Physics

Moulton Hall 311

Campus Box 4560

Normal,
Il
61790-4560

309-438-8756

Computer Golf Putting Championship

For a given landscape, the participant should determine, using a computer program, the initial direction and speed of the ball. The ideal putting condition will enable the golf ball to "roll" toward the flag and stop at a spot closest to the "hole" mark. The golf ball will be assumed to slide on the surface of the green under the influence of gravity, and a velocity independent kinetic frictional force proportional to the normal support. The ball is restricted to the surface (therefore no chipping). Only one putt will be allowed per hole. Nine different greens (see below) will be played. The person with the smallest sum of distances from the hole wins the competition.

### The Challenge

Write a Fortran subroutine CHOICE (X, Y, ANGLE, SPEED), which takes the given center location of five hills, [X(1), Y(1)], [X(2), Y(2)], ..., [X(5), Y(5)], as input to produce as output the initial putting direction (in degrees) and speed (in m/s). Each golf green will be defined via a landscape function z (x, y) = Sum {j=1 to 5} exp{ -[ (x-xj)2 + (y-yj)2 ] / 2 }. Here x and y are the horizontal coordinates (in meters) and z the height (in meters). The ball placement will be at (x = 0 m, y = 0 m) on the green and the hole mark will be at (x = 15 m, y = 15 m). Five hills will be present on each green, all with maximum height of 1 m. The centers of five hills will be determined by a random number generator during the competition. Use g = 10 m/s2 for the acceleration due to gravity and m = 0.1 for the coefficient of kinetic friction.

The Prize committee will load your control subroutine CHOICE into its master code which simulates the motion of the golf ball. The distance between the ball's final position and the hole will be measured after each putt. When this total distance is the same for two competitors the one with the least amount of computing time wins. The total computing time for the nine holes is limited to 5 minutes for each player (on entropy).

### Prize

$300 ( $ 200 for the winning team, $100 for the second best team ).

### Who can participate

Any Physics major in the Department of Physics at ISU.

### Deadline

Day before the last colloquium in the fall semester. The winners will be announced at the last departmental colloquium of the fall 1999 semester.

### Questions

A copy of the Fortran code that simulates the motion of the golf ball for a given green can be obtained from any member of the Skadron Prize committee: Drs. R. Grobe, R.F. Martin, and Q. Su.