Systematic type synthesis of variable -constraint mechanisms

Jun Ma, University of Rhode Island


Methodologies for computer-aided type synthesis of variable-constraint mechanisms (VCMs) are discussed in this dissertation. Two kinds of VCMs are discussed, one-way mechanisms and Geneva mechanisms. ^ In the first chapter of this dissertation, systematic type synthesis algorithms are proposed and discussed. Dual-graph methods are proposed to represent a one-way mechanism that uses only one overrunning clutch, or a Geneva mechanism (rotary or translational), that includes only a pair of Geneva crank/wheel (or crank/slider for translational Geneva mechanism). A dual-graph set of a VCM consists of a 1-DOF graph and a 2-DOF graph. The combination of the 2 graphs reflects the constraint-varying nature of a VCM. ^ The 1-DOF graph of a VCM is, or can be obtained from, a constant-constraint mechanism (CCM) graph. The two graphs of a VCM are related such that the 2-DOF graph can be derived from the 1-DOF graph following specific rules. The graph-deriving process reflects the process of modification of a CCM to obtain a VCM. The dual-graph also includes all necessary information for sketching a VCM. ^ In the second chapter of this dissertation, the proposed methodologies are applied to the type synthesis of a one-way mechanism that is used as the index mechanism of a leaf sampler. The leaf sampler is used to collect a precise amount of leaf material for genetic research purposes. ^ Although this investigation is mainly aimed for the design of one-way mechanisms and Geneva mechanisms, the general idea is applicable to the design of all VCMs. ^

Subject Area

Engineering, Mechanical|Computer Science

Recommended Citation

Jun Ma, "Systematic type synthesis of variable -constraint mechanisms" (1999). Dissertations and Master's Theses (Campus Access). Paper AAI9960030.