Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Institution
Articles 31 - 34 of 34
Full-Text Articles in Mechanical Engineering
The Pseudo-Rigid-Body Model For Dynamic Predictions Of Macro And Micro Compliant Mechanisms, Scott Marvin Lyon
The Pseudo-Rigid-Body Model For Dynamic Predictions Of Macro And Micro Compliant Mechanisms, Scott Marvin Lyon
Theses and Dissertations
This work discusses the dynamic predictions of compliant mechanisms using the Pseudo-Rigid-Body model (PRBM). In order to improve the number of mechanisms that can be modeled, this research develops and identifies several key concepts in the behavior of beam segments where both ends are fixed to a rigid body (fixed-fixed flexible segments). A model is presented, and several examples are discussed. The dynamic behavior of several compliant segments is predicted using the PRBM and the results are compared to finite element analysis and experimental results. Details are presented as to the transient behavior of a typical uniform rectangular cross section …
Thermal Microactuators For Microelectromechanical Systems (Mems), Rebecca Cragun
Thermal Microactuators For Microelectromechanical Systems (Mems), Rebecca Cragun
Theses and Dissertations
Microactuators are needed to convert energy into mechanical work at the microscale. Thermal microactuators can be used to produce this needed mechanical work. The purpose of this research was to design, fabricate, and test thermal microactuators for use at the microscale in microelectromechanical systems (MEMS). The microactuators developed were tested to determine the magnitude of their deflection and estimate their force. Five groups of thermal microactuators were designed and tested. All of the groups used the geometrically constrained expansion of various segments to produce their deflection. The first group, Thermal Expansion Devices (TEDs), produced a rotational displacement and had deflections …
On-Chip Actuation Of Compliant Bistable Micro-Mechanisms, Michael S. Baker
On-Chip Actuation Of Compliant Bistable Micro-Mechanisms, Michael S. Baker
Theses and Dissertations
Two compliant bistable micro-mechanisms have been developed which can be switched in either direction using on-chip thermal actuation. The energy storage and bistable behavior of the mechanisms are 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 designs were optimized to reduce their required rotation, allow them to be switched using linear-motion thermal actuators. The modeling theory and analysis are presented for several design iterations. Each iteration was successfully fabricated and tested using either the MUMPs or …
Predicting The Effects Of Dimensional And Material Property Variations In Micro Compliant Mechanisms, Jonathan W. Wittwer
Predicting The Effects Of Dimensional And Material Property Variations In Micro Compliant Mechanisms, Jonathan W. Wittwer
Theses and Dissertations
Surface micromachining of micro-electro-mechanical systems (MEMS), like all other fabrication processes, has inherent variation that leads to uncertain material and dimensional parameters. To obtain accurate and reliable predictions of mechanism behavior, the effects of these variations need to be analyzed. This thesis expands already existing tolerance and uncertainty analysis methods to apply to micro compliant mechanisms. For simple compliant members, explicit equations can be used in uncertainty analysis. However, for a nonlinear implicit system of equations, the direct linearization method may be used to obtain sensitivities of output parameters to small changes in known variables. This is done by including …