Distributed shape optimization of compliant mechanisms using intrinsic functions

Chao-Chieh Lan, Yung Jen Cheng

Research output: Chapter in Book/Report/Conference proceedingConference contribution

6 Citations (Scopus)

Abstract

A compliant mechanism transmits motion and force by deformation of its flexible members. It has no relative moving parts and thus involves no wear, lubrication, noise, and backlash. Compliant mechanisms aims to maximize flexibility while maintaining sufficient stiffness so that satisfactory output motion can be achieved. When designing compliant mechanisms, the resulting shapes sometimes lead to rigid-body type linkages where compliance and rotation is lumped at a few flexural pivots. These flexural pivots are prone to stress concentration and thus limit compliant mechanisms to applications that only require small-deflected motion. To overcome this problem, a systematic design method is presented to synthesize the shape of a compliant mechanism so that compliance is distributed more uniformly over the mechanism. With a selected topology and load conditions, this method characterizes the free geometric shape of a compliant segment by its rotation and thickness functions. These two are referred as intrinsic functions and they describe the shape continuously within the segment so there is no abrupt change in geometry. Optimization problems can be conveniently formulated with cusps and intersecting loops naturally circumvented. To facilitate the optimization process, a numerical algorithm based on the generalized shooting method will be presented to solve for the deflected shape. Illustrative examples will demonstrate that through the proposed design method, compliant mechanisms with distributed compliance will lessen stress concentration so they can be more robust and have larger deflected range. It is expected that the method can be applied to design compliant mechanisms that have a wide variety of applications from precision instruments to biomedical devices.

Original languageEnglish
Title of host publication2007 Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, DETC2007
Pages3-11
Number of pages9
DOIs
Publication statusPublished - 2008 Jun 17
Event31st Mechanisms and Robotics Conference, presented at - 2007 ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, IDETC/CIE2007 - Las Vegas, NV, United States
Duration: 2007 Sep 42007 Sep 7

Publication series

Name2007 Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, DETC2007
Volume8 PART A

Other

Other31st Mechanisms and Robotics Conference, presented at - 2007 ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, IDETC/CIE2007
CountryUnited States
CityLas Vegas, NV
Period07-09-0407-09-07

Fingerprint

Compliant mechanisms
Distributed Optimization
Compliant Mechanism
Shape Optimization
Shape optimization
Compliance
Stress Concentration
Pivot
Design Method
Motion
Stress concentration
Shooting Method
Lubrication
Cusp
Process Optimization
Rigid Body
Numerical Algorithms
Linkage
Stiffness
Maximise

All Science Journal Classification (ASJC) codes

  • Computer Graphics and Computer-Aided Design
  • Computer Science Applications
  • Mechanical Engineering
  • Modelling and Simulation

Cite this

Lan, C-C., & Cheng, Y. J. (2008). Distributed shape optimization of compliant mechanisms using intrinsic functions. In 2007 Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, DETC2007 (pp. 3-11). (2007 Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, DETC2007; Vol. 8 PART A). https://doi.org/10.1115/DETC2007-34191
Lan, Chao-Chieh ; Cheng, Yung Jen. / Distributed shape optimization of compliant mechanisms using intrinsic functions. 2007 Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, DETC2007. 2008. pp. 3-11 (2007 Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, DETC2007).
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Lan, C-C & Cheng, YJ 2008, Distributed shape optimization of compliant mechanisms using intrinsic functions. in 2007 Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, DETC2007. 2007 Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, DETC2007, vol. 8 PART A, pp. 3-11, 31st Mechanisms and Robotics Conference, presented at - 2007 ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, IDETC/CIE2007, Las Vegas, NV, United States, 07-09-04. https://doi.org/10.1115/DETC2007-34191

Distributed shape optimization of compliant mechanisms using intrinsic functions. / Lan, Chao-Chieh; Cheng, Yung Jen.

2007 Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, DETC2007. 2008. p. 3-11 (2007 Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, DETC2007; Vol. 8 PART A).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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Lan C-C, Cheng YJ. Distributed shape optimization of compliant mechanisms using intrinsic functions. In 2007 Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, DETC2007. 2008. p. 3-11. (2007 Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, DETC2007). https://doi.org/10.1115/DETC2007-34191