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Design, Fabrication, Modeling And Characterization Of Electrostatically-Actuated Silicon Membranes, Brian C. Stahl
Design, Fabrication, Modeling And Characterization Of Electrostatically-Actuated Silicon Membranes, Brian C. Stahl
Master's Theses
This thesis covers the design, fabrication, modeling and characterization of electrostatically actuated silicon membranes, with applications to microelectromechanical systems (MEMS). A microfabrication process was designed to realize thin membranes etched into a silicon wafer using a wet anisotropic etching process. These flexible membranes were bonded to a rigid counterelectrode using a photo-patterned gap layer. The membranes were actuated electrostatically by applying a voltage bias across the electrode gap formed by the membrane and the counterelectrode, causing the membrane to deflect towards the counterelectrode. This deflection was characterized for a range of actuating voltages and these results were compared to the …
Computational Analysis Of Input-Shaping Control Of Microelectromechanical Mirrors, Thomas Starling
Computational Analysis Of Input-Shaping Control Of Microelectromechanical Mirrors, Thomas Starling
All Theses
Advances in micromachining technology have enabled the design and development of high performance microelectromechanical systems (MEMS). There is a pressing need for control techniques that can be used to improve the dynamic behavior of MEMS such as the response speed and precision. In MEMS applications, open-loop control is attractive as it computes a priori the required system input to achieve desired dynamic behavior without using feedback, thus eliminating the problems associated with closed-loop MEMS control. While the input-shaping control is attractive due to its simplicity, the effectiveness of this control approach depends on the accuracy of the model that is …
Design And Testing Of A Pumpless Microelectromechanical System Nanoinjector, Quentin Theodore Aten
Design And Testing Of A Pumpless Microelectromechanical System Nanoinjector, Quentin Theodore Aten
Theses and Dissertations
A deeper understanding of human development and disease is made possible partly through the study of genetically modified model organisms, such as the common mouse (Mus musculus). By genetically modifying such model organisms, scientists can activate, deactivate, or highlight particular characteristics. A genetically modified animal is generated by adding exogenous (foreign) genetic material to one or more embryonic cells at their earliest stages of development. Frequently, this exogenous genetic material consists of specially engineered DNA, which is introduced into a fertilized egg cell (zygote). When successfully introduced into the zygote, the exogenous DNA will be incorporated into the …
Microgripper Force Feedback Integration Using Piezoresistive Cantilever Structure, Todd R. Simon
Microgripper Force Feedback Integration Using Piezoresistive Cantilever Structure, Todd R. Simon
Theses
Force feedback is an important feature in most microgripper applications, but it is commonly overlooked. To successfully implement this feature, a cantilever structure has been designed and fabricated to integrate force feedback into a microhand gripper. The piezoresistive properties of doped polysilicon are used to transduce the mechanical stress of an object pressing against the cantilever sensor, resulting in a change in resistance or voltage capable of being monitored with external hardware. The force sensing structure was designed to have a fabrication process compatible with that of the microhand, allowing for their eventual integration. This fabrication process uses both bulk …
Analysis Of The Nonlinear Vibrations Of Electrostatically Actuated Micro-Cantilevers In Harmonic Detection Of Resonance (Hdr), Jonathan Taylor
Analysis Of The Nonlinear Vibrations Of Electrostatically Actuated Micro-Cantilevers In Harmonic Detection Of Resonance (Hdr), Jonathan Taylor
All Theses
Micro- and nano-cantilevers have the potential to revolutionize physical, chemical, and biological sensing; however, an accurate and scalable detection method is required. In this work, a fully electrical actuation and detection method is presented, known as the Harmonic Detection of Resonance (HDR). In HDR, harmonic components of the current are measured to determine the cantilever's resonance frequency. These harmonics exist as a result of nonlinearities in the system, principally in the electrostatic actuation force. In order to better understand this rich harmonic structure, a theoretical investigation of the micro-cantilever is undertaken. Both a lumped parameter model and a more accurate …
Multi-Physics Modeling And Calibration For Self-Sensing Of Thermomechanical In-Plane Microactuators, Kendall B. Teichert
Multi-Physics Modeling And Calibration For Self-Sensing Of Thermomechanical In-Plane Microactuators, Kendall B. Teichert
Theses and Dissertations
As technology advances and engineering capabilities improve, more research has focused on microscopic possibilities. Microelectromechanical systems (MEMS) is one area that has received much attention recently. Within MEMS much research has focused on sensing and actuation. This thesis presents work on a particular actuator of interest, the thermomechanical in-plane microactuator (TIM). Recent work has shown the possibility of a novel approach of sensing mechanical outputs of the TIM without ancillary sensors. This sensing approach exploits the piezoresistive property of silicon. However, to implement this approach a full model of the TIM would need to be obtained to describe the physics …
Characterizing The Three-Dimensional Behavior Of Bistable Micromechanisms, Brian B. Cherry
Characterizing The Three-Dimensional Behavior Of Bistable Micromechanisms, Brian B. Cherry
Theses and Dissertations
Compliant bistable micromechanisms have been proposed for use in applications such as switches, relays, shutters, and sensing arrays. Unpublished laboratory testing suggests that off-axis forces may affect the bistable nature of fully compliant bistable micromechanisms (FCBMs). The actuation forces required to snap the FCBM from one stable equilibrium position to another can be altered if the off-axis forces are applied to the mechanism during transition between stable positions. Understanding the three-dimensional characteristics of these mechanisms and the effect of eccentric loading conditions would be helpful in design and analysis of FCBMs. Two 3-D FEA models were developed for analysis and …
The Development Of An In Vivo Spinal Fusion Monitor Using Microelectromechanical (Mems) Technology To Create Implantable Microsensors, Lisa Anne Ferrara
The Development Of An In Vivo Spinal Fusion Monitor Using Microelectromechanical (Mems) Technology To Create Implantable Microsensors, Lisa Anne Ferrara
ETD Archive
Surgical fusion of the spine is a conventional approach, and often last alternative, to the correction of a degenerative painful spinal segment. The procedure involves the surgical removal of the intervertebral disc at the problematic site, and the placement of a bone graft that is commonly harvested from the patients iliac crest and placed within the discectomized space. The surrounding bone is expected to incorporate and remodel into the bone graft to eventually provide an immobilized site. Spinal instrumentation often accompanies the bone graft to provide further immobility to the targeted site, thus augmenting the fusion process. However, the status …
Mems (Micro-Electro-Mechanical-Systems) Based Microfluidic Platforms For Magnetic Cell Separation, Pulak Nath
Mems (Micro-Electro-Mechanical-Systems) Based Microfluidic Platforms For Magnetic Cell Separation, Pulak Nath
ETD Archive
Microfluidic platforms for magnetic cell separation were developed and investigated for isolation of magnetic particles and magnetically tagged cells from a fluidic sample. Two types of magnetic separation platforms were considered: an Isodynamic Open Gradient Magnetic Sorter (OGMS) and a multistage bio-ferrograph. Miniaturized magnets were designed using magnetostatic simulation software, microfluidic channels were fabricated using microfabrication technology and magnetic separation was investigated using video microscopy and digital image processing. The isodynamic OGMS consisted of an external magnetic circuit and a microfabricated channel (biochip) with embedded magnetic elements. The biochip is placed inside the magnetic field of the external circuit to …
Mems Transducer For Hearing Aid Device, Houwen Tang
Mems Transducer For Hearing Aid Device, Houwen Tang
Electronic Theses and Dissertations
A study of implantable middle ear MEMS piezoelectric transducer for hearing aids was developed. The physical vibration deflection at the tip of the transducer is simulated using finite element method. Further, a study of thermoelastic damping effect of four designed MEMS mirrors used as resonators is presented. An optical measurement system based on Mach-Zehnder interferometer is
Integrated Blood Separation And Blood Tests On A Microfluidics-Based Lab-On-Cd Device, Jinlong Zhang
Integrated Blood Separation And Blood Tests On A Microfluidics-Based Lab-On-Cd Device, Jinlong Zhang
Digitized Theses
As the development of microfabrication technology, Micro Electro-Mechanical System (MEMS) devices have been extensively explored for practical biological and chemical applications. One fast growing research area of MEMS is the development of portable, all-in-one, point-of-care Lab-On-a-Chip devices. Lab-On-CD device is one of the most important branches of Lab-On-a-Chip technology through implementing experiments on a rotating disk. In this thesis, a microfluidics-based Lab-On-CD device has been developed where the whole process of blood separation and blood tests can be performed automatically and sequentially in one experiment. This Lab-On-CD device was fabricated using microfabrication techniques. The centrifugal force is adopted as the …