Force measurements near a natural frequency of a measurement system using inverse filters

Abstract

Accurate time-resolved force measurements for complex experimental systems are important for minimizing erroneous and misleading data. These measurements become difficult when a natural frequency of the system is in or near the expected frequency domain of the time-varying force being applied. In the cases where it is not possible to avoid this occurrence, the experimenter typically abandons the setup. This work presents an inverse filter method to compensate for the dynamic response of the measurement system. A two degree-of-freedom measurement system is used to obtain force measurements with dominant forcing frequencies above and below the first natural frequency of the system. The results show that inverse filtering can be used along with digital low pass filters to correct amplification and phase shift due to the dynamic response of the measurement system to within ±4.0 % of total forcing amplitude and ±5.0∘. A simple cam follower mechanism is proposed as a method of low-frequency dynamic testing.

Document Details

Document Type
Pub Defense Publication
Publication Date
Dec 02, 2021
Source ID
10.1088/1361-6501/ac3943

Entities

People

  • James D. Brooks
  • Melissa A. Green
  • Seth A Brooks

Organizations

  • Office of Naval Research Global

Tags

Fields of Study

  • Engineering

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Radar Systems Engineering.
  • Theoretical Analysis.