Optimization and application of a low-density epoxy composite coating for autonomous air-to-deep sea vehicles

Abstract: Unmanned, autonomous air-to-sea vehicles, fully capable of transitioning between the two mediums, have only recently become technologically possible and have attracted great interest due to their numerous applications. However, current vehicles are unable to withstand the environmental conditions of the deep sea, especially with regards to their electronics. Previous methods for protecting electronics in the deep sea are not optimized for transitions to air. Here, a novel, lightweight, thermally-conductive, easily processed, mechanically robust, epoxy-based nanocomposite coating is presented. This material was developed with the intention of bringing the multi-domain air-water drone, known as the Naviator, to the deep ocean. In this work, the coating is thoroughly characterized and demonstrated to protect electronics submerged in water at high-pressure benchtop conditions as well as in an actual deep sea mission. The coating is also contrasted against unmodified epoxy, as well as commercial syntactic foam, and deemed superior for this application. Graphical Abstract: [Figure not available: see fulltext.]