On a Generalized Approach for Design of Compliant Mechanisms Using the Pseudo-Rigid-Body Model Concept


This paper provides a generalized approach for the design of compliant mechanisms. The paper discusses the implicit uncoupling, between the kinematic and energy/torque equations, enabled by the pseudo-rigid-body model concept, and utilizes it for designing a variety of compliant mechanism types for a wide-range of user specifications. Pseudo-rigid-body four-bar mechanisms, with one to four torsional springs located at the revolute joints, are considered to demonstrate the design methodology. Mechanisms are designed for conventional tasks, such as function, path and motion generation, and path generation with prescribed timing, with energy/torque specified at the precision-positions. State-of-the-art rigid-body synthesis techniques are applied to the pseudo-rigid-body model to satisfy the kinematic requirements. Energy/torque equations are then used to account for the necessary compliance according to the user specifications. The approach utilizes a conventional, simple yet efficient optimization formulation to solve energy/torque equations that allow a designer to i) achieve realistic solutions, ii) specify appropriate energy/torque values, and iii) reduce the sensitivities associated with the 'synthesis with compliance' approach. A variety of examples are presented to demonstrate the applicability and effectiveness of the approach. All of the examples are verified with the finite element software ANSYS®.

Meeting Name

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


Mechanical and Aerospace Engineering

Keywords and Phrases

Design; Finite element method; Kinematics; Mechanisms; Rigid structures; Specifications; Systems analysis; Finite element software; Four-bar mechanisms; Optimization formulations; Path and motion generation; Pseudo rigid bodies; Pseudo-rigid body models; Synthesis techniques; Synthesis with compliance; 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