Of all the interesting cases of equipment brought onto the ship, the box containing ornament-like sensor bots was one of the most exciting to explore. Housed in a clear polycarbonate sphere sealed together with a vacuum pressure process, each sensor contained only one battery to power a remarkable suite of oxygen, pH, and temperature sensors. Unique sensing films on the surfaces of the balls (visible in the picture as translucent thumbnail-sized circles) changed the way they interacted with light in reaction to environmental water quality. Intense flashes of blue light appeared regularly near Dr. Cody Youngbull's work station, where he tested each sphere before we mounted them in protective containers for deployment. The bots communicate scientific data through these patterns of flashes. A high-speed camera records the sequences for analysis onboard the ship. It is amazing that these tiny spheres are sealed with a single O-ring, and that they can withstand the pressure at a couple thousand meters of depth! Since they are positively buoyant and easily attachable, the spheres can be mounted in a variety of ways…at the end of a string, suspended vertically throughout the water column, deployed as an array of sensors throughout the OOI network…the possibilities for the use of these instruments in remote sensing are fairly impressive (and we haven't even explored the option of biodegradable instruments yet!).
It takes the work of a few students, Cody, and James to put the sensor bots together, test them, and place them on the stand that they'll be deployed on. The Captain of the ship even stops by to offer suggestions. It's interesting to see how much work goes into the design of the spheres, in additional to pre-deployment planning. The stand is made with large bungee cord loops so that ROPOS can work easily to uncover the spheres once the stand is in the water, and the weight of the whole structure ensures that it will stay upright even on uneven slopes (i.e. basalt in its many forms). It will be interesting to see how the system works once it is at the bottom of the ocean.