Studies on the ocean and all its biology is something that still needs to be constantly optimized. In order to facilitate the work of acquiring images, engineers at MIT (Massachusetts Institute of Technology) built a wireless and battery-free camera. The object consumes little power underwater while taking pictures that can be reconstructed later.
The information was disclosed in a document on the Nature Communications. The device can take color pictures of remote underwater objects and transmit the data for real-time monitoring of underwater environments. All this in different situations, even in dark environments.
The objectives are many, but include the discovery of rare species, monitoring of ocean currents and pollution, as well as monitoring commercial and military operations.
According to the authors of the invention, this creation is more than necessary:
Despite advances in underwater imaging, most marine organisms and oceans remain unknown and unobserved. Existing methods for underwater photos and videos are unsuitable for scalable, long-term observations because they require wires and the like for power and communication.
With that, MIT engineers worked to develop a design that would use as few parts as possible, but would be self-sufficient. The team created a prototype to perform different tests in order to prove the functionality of the object. It worked out.
Cheap parts and unconventional technology
Keeping with the plan to produce a wireless camera, without a battery, but that would take quality photos, the team made a simple and functional design.
The first solution was to use LEDs in blue, red and green. Thus, the equipment uses the red LED for lighting and captures the image with its sensors. The process occurs again with the other two colors. With the blend, it is possible to reconstruct the photo in full color in a post-processing.
In terms of energy, instead of a conventional battery, the project uses a backscatter technology that allows underwater communication. It is known as a “piezo-acoustic backscatter”, modulating reflections of incident underwater sounds to transmit data, one bit at a time.

In the estimates of the authors of the project, the equipment is about 100 thousand times more energy efficient than similar devices or with the same purpose. Plus, MIT’s wireless camera could work for weeks underwater.
With information: ARS Technica.
https://tecnoblog.net/noticias/2022/09/30/para-estudar-o-oceano-mit-criou-camera-sem-fio-e-sem-bateria/