If you’ve ever mushed around or ran across a concoction of cornstarch and water, you will have discovered the joys of non-Newtonian fluids, AKA dilatant or shear-thickening fluids. Unlike water and other boring ol’ Newtonian fluids with a constant viscosity dependent only on temperature & pressure, dilatant materials have flow properties that vary based on applied stress. They are squishy when little force is applied and elastomeric with more force.

The disadvantages of conventional forms of human body protection, which involve a combination of hard-shell plastics and compressible foams, are immediately apparent. Plastics are too heavy and rigid, whereas foams are too bulky and cumbersome–together, they inhibit sensory feedback and greatly restrict freedom of movement. Unfortunately, the latter two are essential to sports (especially winter & motor sports), leaving athletes to choose between total safety or an unimpaired performance.

Richard Palmer has invented an advanced polymer called D3O that has the potential to replace traditional protective gear. It is made with “intelligent molecules” that flow with you as you move but on shock lock together within milliseconds to absorb the impact.


Part microcellular foam and part dilatant fluid, D3O is soft and flexible until it encounters blunt trauma. Sporting good industries, as well as the military, have been clamoring for this light, malleable, orange material which can be seamlessly integrated into anything from sportswear to beanies to tactical body armor (and even iPhone cases).

As Palmer puts it, “It’s the difference between Robocop and Spiderman. Robocop is built with protection around him like a shield; d3o is more like Spiderman, where the protection and the athlete are integrated together. It’s a discrete, small and totally unrestricted layer of protection in the areas where you need it that wouldn’t previously have been possible.” [via CNN]

I’d like to try out one of those beanies with an embedded layer of d30, although having someone hit me on the head with a shovel seems unwise…that Youtube video certainly makes it look safe enough.