SAND SAMPLING APPARATUS Eglin Air Force Base Gina Teofilak Richard Klimas Dan Mortensen Ruben De Sousa

William “Bill” Cooper, MSgt Wes Schuler, LT Brad Breaux, Lalit Chhabildas AFRL/RW Munitions Directorate Air Force Research Laboratory Phil Metzger Granular Mechanics & Surface Systems Lab NASA, Kennedy Space Center Victor Giurgiutiu Air Force Office of Scientific Research Sand Fracture Mechanisms During High-Speed Sand Impacts 2

Overview- The Experiment 3  Target filled with 3000 lbs. sand  Projectile shot through the target  Documentation of virgin & impacted sand grain morphology

Introduction INTRODUCTION 4 Fractured sand Projectile Target shot line

Current Design 5  Driven by a chain  Steel rod with supports (x-axis)  Actuators with threaded rods (y & z axes)  3 motors automated  Control system Z X Y

E GLIN V ISIT 10/31/2008 Current Design Cont’d. 6

7 Fabrication - CNC to fabricate end plates and bearing holders - Mill to construct side plates and lead screw nut - Lathe to turn down lead screws and support rods

8 Actuators - Y and Z actuators same concept, but different sizes - Same spacing between stabilizer rods and lead screw - Y actuator is 24in x 8in - Z actuator is 17in x 8in -Z actuator mounted vertically onto the horizontally mounted y actuator - Bearing holders and lead screw nut were precisely fabricated to prevent binding and torque forces

9 Remaining Fabrication  Two 8ft rails with supports every 1ft (x axis)  Various parts that attach the y actuator to x axis:  clamp for the chain  end supports that will house the pulleys for the chain  Group will be going down to Clearwater this weekend to fabricate these parts, and create a base to mount the apparatus for experimentation

Required Torque Needed (oz*in) X movement20 Y movement40 Z movement20 10  Using encoders and servo controllers to do motion control  Became expensive - >$200 per motor Wall SocketPower SupplyMicroprocessor Encoder Motor Motor Controller – Servo Controller Motor X Direction Movement Z Direction Movement Y Direction Movement Electronics- Old Method Motor Controller – Servo Controller

11 Electronics- New Method  Using switches and hard coding to get motion control desired.  Cheaper but more time consuming. Wall SocketPower SupplyMicroprocessor Switches Motor ControllerMotor Motor Controller Motor X Direction Movement Z Direction Movement Y Direction Movement Cabling ran close to the mechanism in twisted pairs and attached away from moving parts. Electronics are being enclosed in a plastic enclosure for protection from the environments.

REFERENCES 1.Cooper, William “Bill”, MSgt Wes Schuler, AFRL/RW Munitions Directorate Air Force Research Laboratory 2.Mortensen, Charles, Owner, Dynatech Associates 3.Dr. Chiang Shih, FAMU-FSU College of Engineering, Mechanical 4.Dr. Daudi Waryoba, FAMU-FSU College of Engineering, Mechanical 12