Design and Construction of an ROV for Underwater Exploration

TLDR

The study presents a compact 18.41 cm × 29.50 cm × 33.50 cm, 15.64 kg ROV designed to capture real‑time underwater video via Ethernet. The ROV uses six brushless motors controlled by a smart PID controller with 1 µs pulse‑width modulation, runs on a Raspberry Pi 3 with multithreading for simultaneous motion, temperature sensing, and 800 × 640 video capture, and is operated through a cross‑platform Python GUI. Experiments show the ROV can capture 42 fps video, reach 100 m depth, and is suitable for surveillance, maintenance, and measurement tasks.

Abstract

The design of a remotely operated vehicle (ROV) with a size of 18.41 cm × 29.50 cm × 33.50 cm, and a weight of 15.64 kg, is introduced herein. The main goal is to capture underwater video by remote control communication in real time via Ethernet protocol. The ROV moves under the six brushless motors governed through a smart PID controller (Proportional + Integral + Derivative) and by using pulse-wide modulation with short pulses of 1 μs to improve the stability of the position in relation to the translational, ascent or descent, and rotational movements on three axes to capture images of 800 × 640 pixels on a video graphic array standard. The motion control, 3D position, temperature sensing, and video capture are performed at the same time, exploiting the four cores of the Raspberry Pi 3, using the threading library for parallel computing. In such a way, experimental results show that the video capture stage can process up to 42 frames per second on a Raspberry Pi 3. The remote control of the ROV is executed under a graphical user interface developed in Python, which is suitable for different operating systems, such as GNU/Linux, Windows, Android, and OS X. The proposed ROV can reach up to 100 m underwater, thus solving the issue of divers who can only reach 30 m depth. In addition, the proposed ROV can be useful in underwater applications such as surveillance, operations, maintenance, and measurement.