Distributed shape optimization of compliant mechanisms using intrinsic functions
Journal Volume
8 PART A
Start Page
3
End Page
11
ISBN (of the container)
0791848035
9780791848098
0791848027
9780791848067
9780791848043
9780791848036
9780791848074
0791848094
0791848043
9780791848029
Date Issued
2008
Author(s)
Cheng, Yungjen
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.
Event(s)
31st Mechanisms and Robotics Conference, presented at - 2007 ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, IDETC/CIE2007
Subjects
Compliant Mechanisms
Distributed Compliance
Shape Optimization
Shooting Method
Design
Mechanisms
Numerical Methods
Shape Optimization
Stress Concentration
Distributed Compliances
Intrinsic Functions
Load Condition
Lubrication /
Moving Parts
Output Motion
Rigid Body
Shape-optimization
Shooting Methods
Systematic Design Methods
Compliant Mechanisms
Publisher
American Society of Mechanical Engineers (ASME)
Description
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. conference code:72173
Type
conference paper