Reusable Stacked Design V. 4

1. Reusable Stacked Design V. 4 Key Exceeds Requirement Tom Amundson, Drew Hanken, Laura Limon & Jacob Pinello Partially Meets Requirement Problem Does Not Meet Requirement Background Solution A gas gun fires a projectile contained within a sabot down the barrel of the gun. The sabot is then stripped from around the projectile using some form of a stripping mechanism. ITT Exelis ‘ current design utilizes a stripping mechanism consisting of two steel plates mounted on four arms within a catch tank. ITT Exelisrequested the design and implementation of a stripping mechanism to reduce cost while maintaining safety with the velocity of the sabot at 2710 ft/s, allowing for multiple projectiles and projectile sizes. The cost was not to exceed $500 per shot. Customer Requirements Upon consideration of the customer requirements and FEA analysis, the Reusable Stacked Design V.4 was chosen. By interrupting the pressure wave experienced on the back plate that occurs at impact, the load was reduced. Modeling and Simulation Research Testing Design • The original design was modeled and compared to previous test data • Maximum displacement was .1181 inches at the sabot impact location • Stress and deformation were reduced on the arms according to simulation results • The final design employed the original arm supports • The 6x1x6” steel plate with the stripping rod was located at the front of the layers • Using a laser, the stripping rod was aligned with the barrel of the gun • Prior to actual firing of the gun, the RSDV.4 had to be aligned within the tank Testing Results • 16 layers of alternating steel, plastic, rubber, and aluminum were placed in front of the 12x1x12” steel back plate • Each layer was machined with four holes for four 6” rods to be inserted through • The stack was bolted using the rods to the steel back plate • The total thickness of the stack was 3.5” • Misalignment of the barrel and the stripping rod would result in: • Projectile becoming lodged in design • Damage to the catch tank • Failure of the stripping device • Pre-test predictions: • Non-reusable layers of aluminum, rubber, and plastic • Non-reusable front 6x1x6” steel plate • Reusability of .25” thick steel layers • Reusability of back 12x1x12” steel plate Future Work • Other opportunities exist for improvement of the gas gun and its performance • Areas include • Arm modification • Sabot redesign • Debris reduction Customer Requirements Review • Following the test shot, the requirements of the customer were evaluated based on performance • Upon survival of four test shots, cost would fall within the green zone for the design excluding the arms • Since some components are not reusable, the design partially meets the multiple use requirement • Post test results: • Non-reusable layers of plastic and rubber • Reusable layers of aluminum and steel • Reusable back 12x1x12” steel plate Acknowledgments We would like to thank the team from ITT Exelis for providing this project to UCCS as well as the use of their facility and their guidance along the way with a special thank you to Josh Majors and Russell Adelgren. We would also like to thank the team in the UCCS machine shop for the use of their machines and the guidance they provided. We would like to give a special thank you to the team at Spire Manufacturing Solutions for their generous donation of time, equipment, and skills. Finally we would like to thank Dr. Gorder and Dr. Sooklal as well as the entire staff at UCCS for their guidance and support.