Characteristic Deflection Domain for Various Compliant Segment Types, and Its Importance in Compliant Mechanism Synthesis and Analysis


Compliant mechanism design inherently requires certain specified displacement boundary conditions to be satisfied. Obtaining realistic solutions for such problem types often becomes a challenge as the number of displacement boundary condition specifications increases. Typically, related failures are attributed to the numerical nature of the solution process. Little attention has been given to the fundamental understanding of the deformation behavior of flexible continuum with respect to its limits of mobility or reach. This paper strives to provide an insight into this aspect of compliant mechanism design. To assist a designer with the specification of realistic and achievable requirements, the concept of characteristic deflection domain has been proposed in the past. This paper systematically develops the characteristic deflection domain for a variety of compliant segment types. The pseudo-rigid-body model (PRBM) representation is utilized for determining the lower and upper boundaries of the deflection domain. The paper further investigates the mobility characteristics of compliant mechanisms comprised of multiple segment types. Case studies are presented that help exemplify the use of the characteristic deflection domain plots. The results suggest that the number, type, and orientation of the compliant segments have a significant effect on the mobility of compliant mechanisms. Thus, care must be exercised by the designer when specifying freechoices/ boundary conditions in compliant mechanisms synthesis and analysis.

Meeting Name

ASME 2014 International Mechanical Engineering Congress and Exposition, IMECE2014 (2014: Nov. 14-20, Montreal, Canada)


Mechanical and Aerospace Engineering

Keywords and Phrases

Boundary conditions; Deflection (structures); Design; Machine design; Mechanisms; Specifications; Case-studies; Characteristic deflection; Deformation behavior; Displacement boundary conditions; Mobility characteristics; Pseudo-rigid-body models; Solution process; Upper boundary; Compliant mechanisms

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Document Type

Article - Conference proceedings

Document Version


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© 2014 American Society of Mechanical Engineers (ASME), All rights reserved.

Publication Date

01 Nov 2014