Recoverable Liquid Nanofoam Energy Absorbers

Executive Summary

Energy absorption and dissipation systems such as shock absorbers, springs, foams and padding are used in a wide variety of applications where protection is required. In the protective equipment segment, users continue to search for new technologies to increase impact resistance with reduced weight. Sports and military helmets in particular, require high direct energy absorption but also complex rotation performance as well, with stringent weight and volume limitations. MSU researchers have recently developed a new technology coined “liquid nanofoam” that offers high energy absorption at low thickness to weight ratios.


Description of Technology

This invention is a novel energy absorption system comprised of a non hazardous liquid, proprietary nanoporous particles and selected levels of additional gas. The entire contents are contained within a suitable enclosed package such as a piston, pouch or pod. Upon application of force, the system remains firm until a designed (and adjustable) threshold force level is achieved. After that, the system absorbs high levels of energy rapidly. The design of the system is such that it can withstand repeated compression cycles and yet retains it’s energy absorption capability after multiple uses.



  • High energy absorption. Excellent for direct impact and rotational energy absorption
  • Stable energy absorption performance in wide operational temperature range
  • Repeatable, systems tested on multiple cycles with identical performance
  • Low volume requirements at similar weights as conventional foam
  • Better performance than commercial TPU football helmet liner
    • 67% reduction in volume at same weight
    • 27% reduction in peak linear acceleration and 46% reduction in transmitted energy under severe impact
    • 66% reduction in peak acceleration and 88% reduction in transmitted rotational energy


  • Sports and military helmets
  • Protective gear (pads, liners, body protection)
  • Military blast protection


Patent Status

Published US application US20220117345A1



Liquid nanofoam description

Technology for helmets

Langmuir article


Licensing Rights

Full licensing rights available



Dr. Weiyi Lu




Patent Information:

For Information, Contact:

Jon Debling
Technology Manager
Michigan State University
Weiyi Lu