Instrumentation and automation have the ability to push the boundaries of current measurement capabilities in marine science and thereby pose unimagined questions. We believe approaches like LaPRAS, a Laboratory Pontoon Remote Aquatic Surveyor, will help researchers do just that. With it, we seek to demonstrate the applicability of a surface based remote controlled seacraft capable of performing vertically profiled measurements and providing underwater imaging to marine research outfits. Our customer, Dr. Brian Silliman of the Duke University Marine Lab, communicated his need for high quality video of fish behavior in marine environments. To meet his needs, the engineering team carefully designed four distinct aspects of a research vessel: a seaworthy body, a dual propeller underwater propulsion system, a waterproof camera housing and sensor module, and a user friendly electronic control system. Each of these components has been designed to be fully modular, in the sense that end-user modification, servicing, and troubleshooting require simple disassembly and reassembly. The UNIX-based control system connects the user to the thrusters, camera, and other sensors through a gamepad controller to create a fully functioning research vessel that can reach a top speed of 2 knots, control the vertical position of a top-down 720p video camera, record video to a local SD card, and stream video to the user. This project gave us an appreciation for the challenges and rewards of marine engineering. We hope that LaPRAS will encourage more collaboration between the engineering and marine science students and faculty at Duke University.
See below for our capstone project final presentation, with more details on the design, control systems, waterproofing of motors and camera, and buoyancy and self-righting ability of our final craft.