Design, Development, and Testing of a Modular Bench-Top Hybrid Rocket Engine Testbed

Hybrid rocket motors offer a compromise between solid and liquid propulsion systems, combining the simplicity and inherent safety of solid motors with the controllability of liquid engines. This paper presents the design and development of a modular, laboratory-scale hybrid rocket motor and benchtop test stand intended for both research and instructional use. The system architecture enables independent design and interchangeability of key subsystems while maintaining conservative operating limits appropriate for a university laboratory environment. The test bench is designed to support systematic investigation of hybrid rocket motor components and to provide hands-on training in fundamental propulsion concepts, including fuel grain design, injector configuration, and regression-rate modeling. Initial testing efforts focus on solid-fuel grains fabricated from polymethyl methacrylate (PMMA) and acrylonitrile butadiene styrene (ABS) and operated with gaseous nitrous oxide.