High-G Accelerometer for Earth-Penetrator Weapons Applications Ldrd Final Report

By Davies, Brady R.

Book Id: WPLBN0000134186
Format Type: PDF eBook
File Size: 2.3 MB
Reproduction Date: 2008

Title:	High-G Accelerometer for Earth-Penetrator Weapons Applications Ldrd Final Report
Author:	Davies, Brady R.
Volume:
Language:	English
Subject:	Government publications, Legislation., Government Printing Office (U.S.)
Collections:	Government Library Collection
Historic Publication Date:
Publisher:	Government Printing Office


Citation APA MLA Chicago Davies, B. R. (n.d.). High-G Accelerometer for Earth-Penetrator Weapons Applications Ldrd Final Report. Retrieved from http://gutenberg.cc/

Excerpt
Excerpt: The acceleration environment experienced by the sensors and electronics in an earth-penetrator weapon is extreme, with average accelerations in the 20,000-G range and peak transient accelerations up to several hundred thousand G’s. Earth penetrators often contact earth, concrete, rocks, or other hard materials while traveling at thousands of feet per second. Sensors must be able to survive both penetrator launch as well as contact and penetration while in some cases distinguishing between each. Commercially available accelerometers used in shock testing of earth-penetrator weapons components are both expensive ($1800 each) and prone to failure.

Table of Contents
Contents 2.0 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 3.0 Integrated Suspended Mass High-G Accelerometer Design . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3.1 High-G Accelerometer Specification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3.2 High-G Accelerometer Mechanical Design (1st Prototype). . . . . . . . . . . . . . . . . . .. . . 7 3.3 High-G Accererometer Electronic Design (1st Prototype) . . . . . . . . . . . . . . . . . . . . . 9 3.4 High-G Accelerometer Test Results (1st Prototype) . . . . . . . . . . . . . . . . . . . . . . . . . . 9 4.0 Revised High-G Accelerometer Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4.1 Finite Element Analysis of Revised High-G Design. . . . . . . . . . . . . . . . . . . . . . . . . . . 11 4.2 Revised High-G Sensor Electronic Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12 4.3 Testing Methods for the Revised Accelerometer Design . . . . . . . . . . . . . . . . . . . . . . 12 4.3.1 Revised Accelerometer Testing Overview. . . . . . . . . . . . . . . . . . . . . . . .. . 13 4.3.2 Revised Design Test Procedures – Laboratory Testing. . . . . . . . . . . . . . . . . 15 4.3.3 Revised Design Test Procedures – Shock Lab Testing. . . . . . . . . . . . . . . . . 16 4.4 Revised Accelerometer Design Test Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 5.0 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 6.0 Future Development. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 6.1 Microelectronics and Testing Electronics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 6.2 Mechanical Electrostatic Damping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 6.3 Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . 19 6.4 Earth-Penetrator System Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . 19 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19 Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 Figures Figure 1: First Prototype Suspended Mass Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . 7 Figure 2: Schematic Mechanical Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Figure 3: Filtered Accelerometer vs. Time Plot for Shock Test at 10 kG . . . . . . . . . . . . . . . . . .. . 10 Figure 4: Bent Beam Design for High-G Accelerometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Figure 5: Deflection Analysis of Revised High-G Accelerometer at 50 kG. . . . . . . . . . . . . . . . . . 12 Figure 6: Block Diagram of Test Setup (1st Prototype) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Figure 7: Block Diagram of Revised Design Electronics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Figure 8: Block Diagram of Test Setup (Revised Design) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Figure 9: SEM Photograph of Fabricated Revised Accelerometer Design . . . . . . . . . . . . . . . . . . .17 Figure 10: Filtered Acceleration vs. Time Plot for Shock Test at 25 kG . . . . . . . . . . . . . . . . . . .. 17 Appendix Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 25 T