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Updated: Aug 5, 2026
07:59
Intermediate Strain Rate Material Characterization with Digital Image Correlation
Published on: March 1, 2019
Elastodynamic mechanical analyzer for high strain-rate mechanical characterization
Yue Luna Zheng1,2, Meredith M Taghon2, Gregory R Freeburn3
1Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, 3141 Chestnut St, PA 19104, USA.
Soft Matter
|August 4, 2026
Summary
We developed the elastodynamic mechanical analyzer (EMA) to study fast-acting latch-mediated spring actuation (LaMSA) systems. EMA measures material properties at high speeds, revealing energy losses and complex behaviors in elastic materials during rapid unloading.
Area of Science:
- Materials Science
- Mechanical Engineering
- Biomimetics
Background:
- Latch-mediated spring actuation (LaMSA) is prevalent in nature and synthetic systems.
- Studying LaMSA requires high-speed experimental tools with high temporal resolution.
- Existing methods are insufficient for characterizing LaMSA component dynamics at relevant speeds.
Purpose of the Study:
- Introduce and validate the elastodynamic mechanical analyzer (EMA).
- Characterize mechanical properties of elastic materials under LaMSA-relevant conditions.
- Investigate energy loss mechanisms during high-rate unloading.
Main Methods:
- Designed and constructed the EMA instrument.
- Performed asymmetric loading and unloading tests on elastic materials.
- Measured force and displacement at high strain rates.
- Calculated instantaneous modulus and analyzed hysteresis.
Main Results:
- EMA successfully characterized elastic spring materials at relevant speeds.
- Coiled metal spring showed rate-independent behavior with dominant external energy losses.
- Latex fabric and polyurethane rubber exhibited strain and strain rate-dependent recoil with significant hysteresis.
- Complex relationships between stress, strain, and strain rate were observed.
Conclusions:
- EMA provides a novel tool for studying material behavior at high strain rates and large deformations.
- Insights into material performance during dynamic strain energy release were gained.
- The study offers valuable data for designing and optimizing LaMSA systems.
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