OpenThruster: An open-source, mostly 3D-printed thruster for marine vehicles.

Area of Science:

• Robotics
• Marine Engineering
• Additive Manufacturing

Background:

• High costs of marine robotic vehicle thrusters limit accessibility for hobbyists and researchers.
• Existing do-it-yourself (DIY) thruster designs often lack detailed performance data and source information.
• Advancements in 3D printing enable the creation of accessible, low-cost marine thrusters.

Purpose of the Study:

• To present an updated and expanded evaluation of the open-source OpenThruster project.
• To focus on performance variability, fabrication methods, and dynamic modeling of DIY marine thrusters.
• To assess the consistency and performance of an accessible, low-cost 3D-printed thruster.

Main Methods:

• Designed and simulated the OpenThruster using open-source software.
• Conducted performance evaluations with off-the-shelf components, including drone motors and a VESC6 driver board.
• Performed bollard thrust measurements in pool water and evaluated propellers from three different 3D printing techniques.

Main Results:

• OpenThruster achieved an average peak thrust of 18 N at 310 W with fabrication costs under $6.
• Tested drone motors from various vendors showed up to 11% thrust variation, but no statistically significant difference.
• Propellers fabricated using different 3D printing methods exhibited significant differences in thrust output.

Conclusions:

• The OpenThruster project provides a viable, low-cost solution for marine robotic vehicle propulsion.
• Performance consistency is achievable with careful component selection, but 3D printing methods significantly impact propeller performance.
• Further research into optimized 3D printing techniques for propellers could enhance thruster efficiency.