George Murphy Baseball Bat Engineering Personal Bat Design
George Murphy Baseball Bat Engineering
Personal Bat • Design Objective – Create a composite baseball bat that will meet certain MOIs (rotational inertia) TARGET SHELL MOI 2200 TARGET FINAL MOI 4200
Design Parameters/Limitations • • Mass Center of Mass 30. 5, 29. 5, or 28. 5 inches long. Only 5 total ounces of resin Photo from: http: //www. ketterin g. edu/~drussell/ba ts-new/batmoi. html
Introduction to Model • Based on braid angle of composite fibers. • Linear density • Thickness model Assumptions and Givens • 8 fluid ounces of resin is spread equally. • Densities • Resin. 63 oz/in 3 • Fibers 1. 1 oz/in 3
Results and Analysis My model was successful at predicting the range of results r rr o 4 . 3 % e SHELL MOI 2208 Final MOI 4017 SPECIFICATIONS Final Weight: 18. 15 oz Cap Weight: 2. 25 oz Knob weight: 2. 75 oz CM: 16. 5 in from Barrel Length: 29. 5 4. 3 5% err o r
Group Project Introduction • Project #2 – Develop a method for determining density at any point based on certain variables. PROGRESSION OF VARIABLES Simplest Translational Velocity Rotational Velocity Radius of Mandrill Braid Angle Packing Distance Amount of Fibers Present Final Target rresin+rfiber=rbat
Angle of the Fiber • Angle determines the amount of fiber present, resin seepage, and fiber movement. • Directly related to density
Data Analysis • Note: 32 is in the denominator because at any there are 32 fibers braiding in each direction
Closing Comments • The final project has a working density model, using the same principles as the previous model. • Incorporates velocities and radii, allowing for more accurate packing distance calculations, thickness modeling… the core of density analysis. • The braid angles/speeds are what we most control, effective to model.
Q&A
- Slides: 10