Do Static Weights Really Matter? Bowl Expo Monday, June 27, 2011

From Ball Motion Study Skid y = -mx + b Hook y = ax 2 + bx + c Roll y = mx + b

Full Factorial Designs # of runs = 2 k 6 Factor Full Factorial 2 6 = 64 runs Fractional Factorial Designs # of runs = 2 k – n 6 Factor Half Fractional 2 6 – 1 = 32 Runs

Sparsity of effects principle Higher order interactions are very rare Resolution 6 Main Effects confounded with 5-way 2-way confounded with 4-way, 3-way 3-way confounded with other 3-way Resolution and Confounding

6 Factor – Half Fraction DOE A center point was also ran.

6 Factor – Half Fraction DOE

From Ball Motion Study Skid y = -mx + b Hook y = ax 2 + bx + c Roll y = mx + b

6 Factor, Half Fraction DOE

Our Understanding of Ball Motion Side Top/Bottom Finger/Thumb

Phase II – Response Surface Design Factorial Design Factorial Design Center point Center point Axial Points Axial Points

3 Factor Central Composite Design

Test Ball Data

3 Factor Central Composite DOE

Influence to Overall Ball Motion - Central Composite

Skid y = -mx + b Hook y = ax 2 + bx + c Roll y = mx + b Terms A B C AA BB CC AB AC BC Intended Path at 49’ X X X Intended Path at 60’ X X X X Average Path at 49’ X X X X

Skid y = -mx + b Hook y = ax 2 + bx + c Roll y = mx + b Terms A B C AA BB CC AB AC BC Vel Dec at 49’ X X Δ in Angle to HP at 49’ X X 1st Transition X X X

Skid y = -mx + b Hook y = ax 2 + bx + c Roll y = mx + b Terms A B C AA BB CC AB AC BC 2nd Transition Skid Slope X X Roll Slope X X

Skid y = -mx + b Hook y = ax 2 + bx + c Roll y = mx + b Terms A B C AA BB CC AB AC BC Total Angular Displacement X X X X Hook Length A Score X X X

Skid y = -mx + b Hook y = ax 2 + bx + c Roll y = mx + b Terms A B C AA BB CC AB AC BC Breakpoint X X 1st Transition to BP X X X 2nd Transition to BP

“Center Point” Analysis Within the -1 oz to +1 oz box

“Center Point” Analysis Average at 49’ Average at 60’ Intended at 60’ 4.06 Roll Slope boards8.536 boards4.548 boards Coefficient Influence From -1 oz to 1 oz of Side Weight

“Center Point” Analysis (60, 22.88) (60, 14.94)

Influence to Overall Ball Motion - Central Composite