Measurement Problems in High Velocity Impact Experiments

Abstract

Reverse-ballistic experiments have been performed at the Ballistic Research Laboratory using a light-gas gun to launch targets against stationary long-rod projectiles instrumented with foil type resistance strain gages. Signals from the strain gages are recorded, measured and analyzed to obtain information about the dynamic behavior of the projectile as it penetrates the target. Signals from the strain gages are commonly divided so that part of the signal may be displayed at higher amplification for better resolution of detail at low strains. Data recorded at different deflection sensitivities and data from gages at diametrically opposed locations on the projectiles are combined for the analysis. Error in the data reduction, especially error in time, is apparent from the poor agreement of the combined data. Different sources of error have been identified but the primary source is optical distortion in the oscilloscope cameras and in the copying camera. This report briefly reviews the instrumented rod experiment and the analytical procedure but primarily considers sources of error. A modified calibration procedure is introduced to minimize the error in the data reduction.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1981
Accession Number
ADA105550

Entities

People

  • William Lawrence

Organizations

  • Ballistic Research Laboratory

Tags

Communities of Interest

  • Advanced Electronics
  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Accuracy
  • Cameras
  • Data Reduction
  • Engineering
  • Gas Guns
  • Light Gas Guns
  • Materials
  • Materials Engineering
  • Measurement
  • Measuring Instruments
  • Mechanical Engineering
  • Mechanics
  • Military Research
  • Recording Systems
  • Square Waves
  • Strain Gages
  • Time Intervals

Readers

  • Geodesy
  • Mechanical Engineering/Mechanics of Materials.
  • ballistics.