Mechanical Engineering Commons^™

Changes In The Mechanical Performance Of An Ortho-Planar Spring After Aging Tests, Lucas F. L. Santos, Larry L. Howell, Jose J. R. D’Almeida

Faculty Publications

This paper analyzed an ortho-planar spring (OPS) compliant mechanism and evaluated its mechanical performance after hygrothermal and ultraviolet radiation aging tests. The aging analysis performed here addresses the performance of compliant mechanisms after aging processes which can help inform the design of future compliant mechanisms. ASTM D638 tensile test type I samples were also submitted to aging to serve as a comparison for OPS samples. The samples were submitted to three different kinds of aging conditions, namely water immersion, oil immersion, and ultraviolet radiation. In conclusion, tensile samples showed significant statistical changes in Young's modulus and elongation at break, whereas …

Symmetric Equations For Evaluating Maximum Torsion Stress Of Rectangular Beams In Compliant Mechanisms, Guimin Chen, Larry L. Howell

Faculty Publications

There are several design equations available for calculating the torsional compliance and the maximum torsion stress of a rectangular cross-section beam, but most depend on the relative magnitude of the two dimensions of the cross-section (i.e.,the thickness and the width). After reviewing the available equations, two thickness-to-width ratio independent equations that are symmetric with respect to the two dimensions are obtained for evaluating the maximum torsion stress

of rectangular cross-section beams. Based on the resulting equations, outside lamina emergent torsional joints are analyzed and some useful design insights are obtained. These equations, together with the previous work on symmetric equations …

Symmetric Equations For Evaluating Maximum Torsion Stress Of Rectangular Beams In Compliant Mechanisms, Guimin Chen, Larry L. Howell

Faculty Publications

There are several design equations available for calculating the torsional compliance and the maximum torsion stress of a rectangular cross-section beam, but most depend on the relative magnitude of the two dimensions of the cross-section (i.e., the thickness and the width). After reviewing the available equations, two thickness-to-width ratio independent equations that are symmetric with respect to the two dimensions are obtained for evaluating the maximum torsion stress of rectangular cross-section beams. Based on the resulting equations, outside lamina emergent torsional joints are analyzed and some useful design insights are obtained. These equations, together with the previous work on symmetric …

Flex-16: A Large-Displacement Monolithic Compliant Rotational Hinge, Robert Mcintyre Fowler, Alex Maselli, Peter Pluimers, Spencer P. Magleby, Larry L. Howell

Faculty Publications

This paper describes the design, analysis, and testing of a large-displacement monolithic compliant rotational hinge, called the Flex-16. The Flex-16 achieves 90 of rotation from monolithic construction and is aimed for application as a compliant satellite deployment hinge. Five prototypes were fabricated from three different materials (polypropylene, titanium, and a carbon nanotube framework) on two different size scales (macro and micro). A parametric finite element model was created to rapidly analyze a variety of design identified during a configuration study. Prototypes were tested for their ability to reach 90 of rotation without failure or self collision, and for their nonlinear …

On-Chip Actuation Of An In-Plane Compliant Bistable Micromechanism, Michael S. Baker, Larry L. Howell

Faculty Publications

A compliant bistable micromechanism has been developed which can be switched in either direction using on-chip thermal actuation. The energy storage and bistable behavior of the mechanism is achieved through the elastic deflection of compliant segments. The Pseudo-Rigid-Body Model was used for the compliant mechanism design, and for analysis of the large deflection flexible segments. To achieve on-chip actuation, the mechanism design was optimized to allow it to be switched using linear motion thermal actuators. The modeling theory and analysis are presented for three design iterations, with two iterations fabricated in the MUMP's process and the third in the SUMMiT …