Design analysis of folding bicycle hinge mechanisms : kinematics, failure modes, user needs, and engineering trade-offs

Abstract

The folding bicycle hinge embodies a critical engineering compromise: it must provide a rigid, safe ride while enabling a compact fold. This thesis establishes an integrated framework to resolve this conflict by bridging engineering analysis with user experience. Through a comparative study, Failure Mode and Effects Analysis (FMEA), and a user survey (N=107), the research identifies and prioritizes hinge design criteria.

Findings reveal that cam mechanism fracture and wear are the highest-risk failure modes. This is reflected in user data, where 21.8% of respondents have experienced hinge locking issues, and 62% distrust non-redundant locks. The study concludes that user priorities mandate a fundamental shift in design trade-offs: stiffness must be prioritized overweight, fail-safe redundancy is essential for user trust, and cost must be concentrated on high-wear components. This work provides an evidence-based blueprint for designing safer, more reliable, and user-centric folding bicycle hinges to promote sustainable urban mobility.