I’m currently a post-doc research fellow at the Institute of Making, UCL. My research is focused on 4D printing – using 3D printing to make smart materials which move in response to changes in their environment. These environmental stimuli could be heat, light, moisture, pressure or magnetism. Common examples of smart materials include pinecones which open and close with changing moisture levels, and bi-metallic strips which bend when heated. Mechanical metamaterials are structures which change shape in often unusual ways, for example if you squash them from above, they get less wide sideways, as opposed to squelching out like most materials would. My research combines 4D printing and mechanical metamaterials to create materials and structures with useful mechanical properties for exoskeletal biomedical devices. It is hoped that these wearable devices will be able to lend support to patients with mobility difficulties.
My EngD project was focused on solid state hydrogen storage materials for portable applications and was sponsored by industrial partner Cella Energy. The central material studied was a composite made from ammonia borane and polyethylene oxide. This energy storage solution offers significant weight advantages over battery storage, which is particularly attractive in the fields of aerospace and portable electronics. A working power system using this material has been demonstrated in a prototype UAV (see above). The challenge was to understand both the science of how this unique material works and to streamline the engineering required for workable systems powered by it.
Freeze-dried ammonia borane-polyethylene oxide composites: Phase behaviour and hydrogen release: A.R Ploszajski, M. Billing, A.S. Nathanson, M. Vickers and S.M. Bennington, International Journal of Hydrogen Energy, 2018, 43, 5645-5656