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This thesis presents the design and prototyping of a torsion spring-driven mechanical starter for potential use in vehicle engines. Torsion springs are considered for this application for three primary reasons. First, a charged spring can deliver the brief but powerful burst of energy required during starting. Second, once the starting energy is stored in a mechanical state, as in a spring, conversion losses are eliminated like those present with the traditional battery to electric motor to engine arrangement. Third, these springs can be inexpensively charged by a motor and battery significantly smaller than those currently in use, thereby reducing the negative environmental impact associated with the disposal of those components. The realized design combines fundamental machine components into a new starter concept, a bench top prototype of which was assembled for validation. Experiments and an accompanying analysis of the starter proved useful for sizing the device for commercial implementation, as well as identifying additional design concerns for a more roadworthy prototype. This work is part of a larger effort on developing mechanisms that use elastic elements to harvest, store, and power devices useful in automotive applications.

Publication Date


Project Designation

Honors Thesis

Primary Advisor

Andrew P. Murray

Primary Advisor's Department

Engineering Technology


Stander Symposium poster

Design, Prototyping and Evaluation of an Elastically-Based Mechanical Starter for Automotive Engines