As part of their city’s beach restoration project, Instructables users Kousheek Chalraborty and Satya Schiavvina, who go by the team name Technovation, needed to construct a small and cheap boat that could assist in mapping the depth of the sea floor at various locations. The design they were able to come up with achieved this goal and even went beyond it by incorporating an autonomous navigation system into their watercraft. 

The hull of the boat was made from a leftover Tupperware container and discarded water bottles, therefore reducing the cost significantly and integrating recycled materials. After the pontoons were attached to the bottom, a pair of brushless DC motors were screwed into place at the top, along with an 11.1v LiPo battery and dual 30-amp ESC modules.

At the core of the robot is a single Arduino Uno that has a custom shield mounted to its top pin headers. This board consists of an nRF24L01 transceiver module for sending/receiving telemetry, a GPS module for tracking position, and a compass module that determines the boat’s orientation. With the firmware loaded onto the Uno, Kousheek and Satya created their own dashboard in Python that allows them to view information in real-time as well as send commands from across the water.

You can read more about this project here on Instructables.