Year

2025

Season

Fall

Paper Type

Master's Thesis

College

College of Computing, Engineering & Construction

Degree Name

Master of Science in Mechanical Engineering (MSME)

Department

Engineering

NACO controlled Corporate Body

University of North Florida. School of Engineering

Committee Chairperson

Dr. John Nuszkowski

Second Advisor

Dr. William Dally

Third Advisor

Dr. Brian Kopp

Department Chair

Alan Harris

College Dean

William Klostermeyer

Abstract

The beach and near shore are among the most economically and environmentally important regions on earth, yet they remain poorly understood due to the challenges of surveying the surf zone and obtaining other important data during high-energy events. Traditional methods such as wading surveys, small watercraft, and specialized vehicles like the coastal research amphibious buggy (CRAB) are limited by safety risks, high mobilization costs, and restricted operating windows. The work conducted in this effort addresses these limitations by continuing development of a remotely operated vehicle (ROV) intended to be operational in harsh surf conditions to collect high-resolution bathymetric and hydrodynamic data.

The proposed system integrates a diesel-hydraulic powertrain mounted on a foldable tripod chassis with three off-road track assemblies for enhanced traction and stability on sandy substrates. Wireless control eliminates the need for a tether, enabling safe remote operation from shore. The design process employed finite element analysis (FEA) for structural integrity and computational fluid dynamics (CFD) for hydrodynamic performance validation. Key design requirements include a maximum operating depth of 8.0 m, capability to withstand 2.0 m breaking waves, and a maximum speed of 2.2 m/s (5 mph).

Modeling and analysis focused on static stability, buoyancy, and drag forces under extreme conditions. Results indicate that snorkel drag poses the greatest overturning risk, with destabilization possible at current speeds exceeding 1.21 m/s. CFD simulations confirmed theoretical drag predictions and highlighted the effectiveness of streamlined fairings, reducing drag by up to sixfold. Wave load analysis demonstrated that while breaking waves exert forces on the vehicle nearly exceeding 10,000 N, structural reinforcements and buoyancy distribution mitigate overturning risks during these transient impacts.

Fabrication combines computer numerical controls (CNC) machining, waterjet sheet cutting, and tungsten inert gas (TIG) welding, using corrosion-resistant materials such as 6061 aluminum and stainless steel fasteners with isolation bushings. System integration utilizes the frame itself, fabricated from cylindrical members, for coolant circulation and fluid storage, thereby minimizing buoyancy and optimizing space. The control architecture, built on an Arduino Mega platform, manages propulsion and steering through proportional hydraulic control modules, implementing a custom designed steering algorithm that adjusts track velocities for precise maneuverability.

Initial laboratory tests validated the wireless control, hydraulic actuation, and cooling performance, though minor issues such as track resonance and uneven coolant distribution are observed, but eventually corrected. Dry land tests of the new vehicle confirmed propulsion capability near the design speed and demonstrated that the steering algorithm performed quite well. Observations suggest further improvements in cooling efficiency and structural damping may be required before the vehicle becomes full operational.

This work resulted in a robust, modular platform for surf zone surveying, bridging the gap between lightweight autonomous rovers and large-scale manned systems. Future efforts will focus on integrating system sensors, refining hydrodynamic fairings, and implementing closed-loop control for enhanced reliability. The successful development of this ROV would provide a significant advancement in the ability to conduct scientific research and engineering in the littoral zone, enabling safer, more efficient data collection during conditions too hazardous for conventional methods.

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