Multipurpose Underwater Exploration Robot (Build18)

@ CMU — Build18 Robotics Hackathon

Introduction

Designing electronics for underwater operation means every decision — frame geometry, cable routing, seal design, thruster placement — interacts with waterproofing. Get one wrong and the whole system fails. This hackathon project built a compact underwater drone with three-thruster omnidirectional propulsion, sealed electronics, and real-time video streaming, designed and assembled within the Build18 timeframe.

Methods

1. Mechanical Design & Waterproofing

Frame built around a sealed electronics bay using acrylic panels, O-ring interfaces, and cable-gland feedthroughs. Thruster positions optimized for surge, sway, and yaw authority while minimizing drag profile.

2. Propulsion & Control Architecture

Three-thruster layout for omnidirectional planar motion. Raspberry Pi coordinated ESC-driven thrusters, handled sensor I/O, and streamed live video to a surface operator. Tuned for stable thrust allocation and responsive teleoperation.

3. Onboard Sensing

Forward-facing camera for real-time video. Pressure and IMU sensors for depth estimation and vehicle stabilization. All computation onboard the Pi for low-latency control.

Results

Achieved stable surge, sway, and yaw control in test-tank trials with no water ingress or electrical faults across multiple sessions. Live video streaming supported operator-guided navigation and visual inspection. All subsystems functioned consistently through full test validation.

Discussion

Underwater environments make integration harder in one specific way: constraints compound. Waterproofing affects thermal management. Thruster placement affects both maneuverability and seal geometry. Cable routing constrains sensor placement. Every subsystem decision affects at least one other. Building this platform under hackathon time pressure forced fast, deliberate prioritization of which constraints to solve first — and which to accept as fixed.

My Contributions

​Designed frame layout, thruster placement, and waterproofed electronics enclosure.

  • Integrated full control architecture: Raspberry Pi, ESC-driven thrusters, and real-time video streaming.

  • Implemented sensing and telemetry for live navigation and vehicle stabilization.

  • Led full-system assembly, waterproofing validation, and hardware-software testing.