Vertical Profiler 2026

Overview

This vertical profiler was designed for the 2026 MATE ROV International Competition at the Fisheries and Marine Institute of Memorial University in Newfoundland and Labrador. The product demonstration took place in an ice tank rated to −25 °C, making low-temperature material behavior a primary design constraint.

The final design is rated for depths up to 5 m and temperatures down to −30 °C, with a material cost below USD 200 per profiler.

I led the project from requirements and task planning through integration and competition. The work confirmed that engineering project management—organizing technical decisions without losing sight of the hardware—is a direction I want to pursue further.

Goals and Design Requirements

The baseline combined the MATE ROV safety rules, the competition environment, internal product goals, and a total project budget of USD 500.

Requirements:

• Rated for at least 3 m depth

• Rated for operation down to −25 °C

• Chemically resistant to glycol-based antifreeze

• Transparent housing

• Professional appearance

• Compliant with MATE ROV safety guidelines

  • Pressure relief valve
  • Battery and power regulations

• Capable of completing the scored vertical-profiling mission

• Built within the USD 500 project budget

Design Philosophy

For this project, we separated requirements from solutions. The competition task defined the need; our requirements stated the performance, safety, environment, and budget the profiler had to satisfy. We did not specify a syringe, servo, enclosure material, or controller until we had compared the options.

That separation kept the design open long enough to make evidence-based decisions. Minimum requirements protected the core mission, while a second set of stretch goals gave the team room to improve the product without putting the schedule at risk.

I translated the requirements into a Work Breakdown Structure, subsystem owners, deadlines, and an initial cost allocation. The schedule and budget were managed together: a subsystem was not fully defined until someone owned both its technical result and its share of the project cost.

An Interface Control Document established the mechanical, electrical, and software boundaries between those subsystems. Connector choices, mounting geometry, voltage levels, message formats, and ownership were agreed on before final integration. That work was less visible than machining or coding, but it prevented many late-stage fit and communication problems.

Major decisions required a weighted trade study or a calculation that answered why one option was better for this application. We returned to the main requirement whenever a feature added cost or schedule pressure. If it did not improve the mission result, reliability, safety, or usability, it did not belong in the baseline design.

The first buoyancy-engine failure tested that process. We had rushed the actuator choice without a complete trade study, and the prototype underperformed. Going back through the comparison led to the simpler rack-and-pinion syringe system now used in both profilers. The revision reinforced the value of slowing down at the decision point rather than paying for a weak assumption during integration.

Mechanical Design

The enclosure is machined from transparent PVC. We selected the material after reviewing its low-temperature behavior and chemical resistance to glycol-based antifreeze near the −30 °C design limit.

Thermal contraction across the operating range was a central mechanical concern. Using PVC throughout the enclosure reduced material mismatch, while O-ring shrinkage and squeeze calculations checked the seal at both room temperature and the −30 °C rated condition.

A team machinist produced two prototypes from the released drawings. Resolving tolerances, tool access, and machining sequence together improved both the design and the quality of the final documentation.

Buoyancy Engine

The buoyancy engine uses a 100 mL syringe driven by a 9 g hobby servo through a rack-and-pinion gear system. The low-cost configuration exceeded the required displacement, supported the 5 m depth rating, and drew approximately 500 mA at stall.

Electronics

A circular integration PCB at the top of the internal structure consolidates the power, control, timing, and status electronics.

We selected the ESP32-C3 for its processing capability, Wi-Fi support, and availability on SparkFun’s compact Pro Micro-style board. That form factor fit within the limited PCB area without requiring a separate communications module.

The design does not use an external antenna, so RF transparency became an enclosure requirement. The 65 mm circular PCB also carries a logic-level shifter, real-time clock, LED array, and buck converter.

Software and Controls

The ESP32-C3 runs as a Wi-Fi access point, allowing a phone or computer to connect directly to the profiler without separate base-station hardware.

The interface includes options for starting and stopping the profile, telemetry output, a depth-over-time graph required by the competition, PID controls, profile and mission controls, and a manual control mode.

Mission settings and controller gains can be changed without reflashing the firmware or opening the enclosure. This shortens the test cycle and reduces unnecessary disturbance of the pressure seal.

Software repository:

View the Vertical Profiler 2026 GitHub repo

Problems and Revisions

Prototype testing exposed two important weaknesses. The first was the buoyancy engine.

The original Actuonix actuator bound under load and did not achieve the predicted displacement. We had selected it before completing a full comparison of the available concepts, so the failure required us to reopen the decision rather than tune around a weak mechanism.

The completed trade study led to the rack-and-pinion syringe design used in both competition-ready profilers.

The second weakness was depth control. A ballast error as small as 0.2 g could shift the neutral point and cause the profiler to oscillate around the wrong depth. We used the vertical profiler simulator to compare control strategies before returning to pool testing.

View the Vertical Profiler Simulator page

Final Result

We completed two competition-ready prototypes on schedule and within the project budget.

At competition, we set the final ballast, completed the product demonstration without a major issue, and earned all 85 points available for the profiler task.

The strongest result was not a single component. It was the connection between requirements, assigned work, documented interfaces, trade studies, and testing. When an early choice failed, that process gave us a clear way to recover.

Supporting Documents

The full Google Drive project folder includes additional documentation, CAD files, PCB schematics, reports, and project files.

View the full VP 2026 Google Drive folder