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Modeling, Simulation And Control Of Microrobots For The Microfactory., Zhong Yang
Modeling, Simulation And Control Of Microrobots For The Microfactory., Zhong Yang
Electronic Theses and Dissertations
Future assembly technologies will involve higher levels of automation in order to satisfy increased microscale or nanoscale precision requirements. Traditionally, assembly using a top-down robotic approach has been well-studied and applied to the microelectronics and MEMS industries, but less so in nanotechnology. With the boom of nanotechnology since the 1990s, newly designed products with new materials, coatings, and nanoparticles are gradually entering everyone’s lives, while the industry has grown into a billion-dollar volume worldwide. Traditionally, nanotechnology products are assembled using bottom-up methods, such as self-assembly, rather than top-down robotic assembly. This is due to considerations of volume handling of large …
Research On Dual-Antenna Gnss-Assisted Mins Navigation Method, Hailu Wang, Su Zhong, Liu Ning, Liu Hong, Guodong Fu
Research On Dual-Antenna Gnss-Assisted Mins Navigation Method, Hailu Wang, Su Zhong, Liu Ning, Liu Hong, Guodong Fu
Journal of System Simulation
Abstract: For the integrated navigation system of the single-antenna GNSS-assisted MEMS strap-down inertial navigation system (MINS), the heading angle divergence is invalid when the vehicle is stationary and linear motion, and the error is large. The method of the dual-antenna GNSS-assisted MINS integrated navigation based on EKF is proposed. The error state model is established, and the extended Kalman filter combined filter (EKF) algorithm is designsed for simulation verification. The driving test is carried out by comparing the high-precision SPAN-CPT. The results show that the yaw angle and pitch angle accuracy are 0.2 RMS, 0.3 RMS, which can be used …
Thermal Management Using Mems Bimorph Cantilever Beams, Ronald A. Coutu Jr., R. S. Lafleur, J. P.K. Walton, Lavern A. Starman
Thermal Management Using Mems Bimorph Cantilever Beams, Ronald A. Coutu Jr., R. S. Lafleur, J. P.K. Walton, Lavern A. Starman
Electrical and Computer Engineering Faculty Research and Publications
This paper examines a passive cooling technique using microelectromechanical systems (MEMS) for localized thermal management of electronic devices. The prototype was designed using analytic equations, simulated using finite element methods (FEM), and fabricated using the commercial PolyMUMPs™ process. The system consisted of an electronic device simulator (EDS) and MEMS bimorph cantilever beams (MBCB) array with beams lengths of 200, 250, and 300 μm that were tested to characterize deflection and thermal behavior. The specific beam lengths were chosen to actuate in response to heating associated with the EDS (i.e. the longest beams actuated first corresponding to the hottest portion of …
Mems-Based Terahertz Photoacoustic Chemical Sensing System, Nathan Glauvitz, Ronald A. Coutu Jr., Ivan R. Medvedev, Douglas T. Petkie
Mems-Based Terahertz Photoacoustic Chemical Sensing System, Nathan Glauvitz, Ronald A. Coutu Jr., Ivan R. Medvedev, Douglas T. Petkie
Electrical and Computer Engineering Faculty Research and Publications
Advancements in microelectromechanical system (MEMS) technology over the last several decades has been a driving force behind miniaturizing and improving sensor designs. In this work, a specialized cantilever pressure sensor was designed, modeled, and fabricated to investigate the photoacoustic (PA) response of gases to terahertz (THz) radiation under low-vacuum conditions associated with high-resolution spectroscopy. Microfabricated cantilever devices made using silicon-on-insulator (SOI) wafers were tested in a custom-built test chamber in this first ever demonstration of a cantilever-based PA chemical sensor and spectroscopy system in the THz frequency regime. The THz radiation source was amplitude modulated to excite acoustic waves in …
Improved Sensitivity Mems Cantilever Sensor For Terahertz Photoacoustic Spectroscopy, Ronald A. Coutu Jr., Ivan R. Medvedev, Douglas T. Petkie
Improved Sensitivity Mems Cantilever Sensor For Terahertz Photoacoustic Spectroscopy, Ronald A. Coutu Jr., Ivan R. Medvedev, Douglas T. Petkie
Electrical and Computer Engineering Faculty Research and Publications
In this paper, a microelectromechanical system (MEMS) cantilever sensor was designed, modeled and fabricated to measure the terahertz (THz) radiation induced photoacoustic (PA) response of gases under low vacuum conditions. This work vastly improves cantilever sensitivity over previous efforts, by reducing internal beam stresses, minimizing out of plane beam curvature and optimizing beam damping. In addition, fabrication yield was improved by approximately 50% by filleting the cantilever’s anchor and free end to help reduce high stress areas that occurred during device fabrication and processing. All of the cantilever sensors were fabricated using silicon-on-insulator (SOI) wafers and tested in a custom …
Thermal Tuning Of Mems Buckled Membrane Actuator Stiffness, Robert A. Lake, Kyle K. Ziegler, Ronald A. Coutu Jr.
Thermal Tuning Of Mems Buckled Membrane Actuator Stiffness, Robert A. Lake, Kyle K. Ziegler, Ronald A. Coutu Jr.
Electrical and Computer Engineering Faculty Research and Publications
The thermal tuning characteristics of a microelectromechanical systems (MEMS) buckled membrane exhibiting regions of both positive and negative stiffness is examined and analyzed using finite element method (FEM) simulation and through experimentation. The membranes are fabricated by releasing a silicon/silicon dioxide (Si/SiO2) laminated membrane from a silicon on insulator (SOI) wafer. The difference in thermal expansion coefficients between Si and SiO2 induces a compressive stress in the SiO2 layer causing out-of-plane buckling of the membrane. This structure is found to have positive and negative stiffness regions when actuated with a transverse force. It is demonstrated that the …
Using Micro-Raman Spectroscopy To Assess Mems Si/Sio2 Membranes Exhibiting Negative Spring Constant Behavior, Lavern A. Starman, Ronald A. Coutu Jr.
Using Micro-Raman Spectroscopy To Assess Mems Si/Sio2 Membranes Exhibiting Negative Spring Constant Behavior, Lavern A. Starman, Ronald A. Coutu Jr.
Electrical and Computer Engineering Faculty Research and Publications
We introduce a novel micro-mechanical structure that exhibits two regions of stable linear positive and negative stiffness. Springs, cantilevers, beams and any other geometry that display an increasing return force that is proportional to the displacement can be considered to have a “Hookean” positive spring constant, or stiffness. Less well known is the opposite characteristic of a reducing return force for a given deflection, or negative stiffness. Unfortunately many simple negative stiffness structures exhibit unstable buckling and require additional moving components during deflection to avoid deforming out of its useful shape. In Micro-Electro-Mechanical Systems (MEMS) devices, buckling caused by stress …
Effect Of Hydrodynamic Force On Microcantilever Vibrations: Applications To Liquid-Phase Chemical Sensing, I. Dufour, E. Lemaire, B. Caillard, H. Debeda, C. Lucat, Stephen M. Heinrich, Fabien Josse, O. Brand
Effect Of Hydrodynamic Force On Microcantilever Vibrations: Applications To Liquid-Phase Chemical Sensing, I. Dufour, E. Lemaire, B. Caillard, H. Debeda, C. Lucat, Stephen M. Heinrich, Fabien Josse, O. Brand
Electrical and Computer Engineering Faculty Research and Publications
At the microscale, cantilever vibrations depend not only on the microstructure’s properties and geometry but also on the properties of the surrounding medium. In fact, when a microcantilever vibrates in a fluid, the fluid offers resistance to the motion of the beam. The study of the influence of the hydrodynamic force on the microcantilever’s vibrational spectrum can be used to either (1) optimize the use of microcantilevers for chemical detection in liquid media or (2) extract the mechanical properties of the fluid. The classical method for application (1) in gas is to operate the microcantilever in the dynamic transverse bending …
Stress Monitoring Of Post-Processed Mems Silicon Microbridge Structures Using Raman Spectroscopy, Lavern A. Starman, Ronald A. Coutu Jr.
Stress Monitoring Of Post-Processed Mems Silicon Microbridge Structures Using Raman Spectroscopy, Lavern A. Starman, Ronald A. Coutu Jr.
Electrical and Computer Engineering Faculty Research and Publications
Inherent residual stresses during material deposition can have profound effects on the functionality and reliability of fabricated Micro-Electro-Mechanical Systems (MEMS) devices. Residual stress often causes device failure due to curling, buckling, or fracture. Typically, the material properties of thin films used in surface micromachining are not well controlled during deposition. The residual stress; for example, tends to vary significantly for different deposition methods. Currently, few nondestructive techniques are available to measure residual stress in MEMS devices prior to the final release etch. In this research, micro-Raman spectroscopy is used to measure the residual stresses in polysilicon MEMS microbridge devices. This …
Srrs Embedded With Mems Cantilevers To Enable Electrostatic Tuning Of The Resonant Frequency, E. A. Moore, Derrick Langley, Matthew E. Jussaume, L. A. Rederis, C. A. Lundell, Ronald A. Coutu Jr., Peter J. Collins, Lavern A. Starman
Srrs Embedded With Mems Cantilevers To Enable Electrostatic Tuning Of The Resonant Frequency, E. A. Moore, Derrick Langley, Matthew E. Jussaume, L. A. Rederis, C. A. Lundell, Ronald A. Coutu Jr., Peter J. Collins, Lavern A. Starman
Electrical and Computer Engineering Faculty Research and Publications
A microelectromechanical systems (MEMS) cantilever array was monolithically fabricated in the gap region of a split ring resonator (SRR) to enable electrostatic tuning of the resonant frequency. The design consisted of two concentric SRRs each with a set of cantilevers extending across the split region. The cantilever array consisted of five beams that varied in length from 300 to 400 μm, with each beam adding about 2 pF to the capacitance as it actuated. The entire structure was fabricated monolithically to reduce its size and minimize losses from externally wire bonded components. The beams actuate one at a time, longest …
A Mems Photoacoustic Detector Of Terahertz Radiation For Chemical Sensing, Nathan Glauvitz, S. Blazevic, Ronald A. Coutu Jr., Michael Kistler, Ivan R. Medvedev, Douglas T. Petkie
A Mems Photoacoustic Detector Of Terahertz Radiation For Chemical Sensing, Nathan Glauvitz, S. Blazevic, Ronald A. Coutu Jr., Michael Kistler, Ivan R. Medvedev, Douglas T. Petkie
Electrical and Computer Engineering Faculty Research and Publications
A piezoelectric Microelectromechanical system (MEMS) cantilever pressure sensor was designed, modeled, fabricated, and tested for sensing the photoacoustic response of gases to terahertz (THz) radiation. The sensing layers were comprised of three thin films; a lead zirconate titanate (PZT) piezoelectric layer sandwiched between two metal contact layers. The sensor materials were deposited on the silicon device layer of a silicon-on-insulator (SOI) wafer, which formed the physical structure of the cantilever. To release the cantilever, a hole was etched through the backside of the wafer and the buried oxide was removed with hydrofluoric acid. Devices were then tested in a custom …
Effects Of Su-8 Cross-Linking On Flip-Chip Bond Strength When Assembling And Packaging Mems, Nathan E. Glavitz, Lavern A. Starman, Ronald A. Coutu Jr., Richard L. Johnson
Effects Of Su-8 Cross-Linking On Flip-Chip Bond Strength When Assembling And Packaging Mems, Nathan E. Glavitz, Lavern A. Starman, Ronald A. Coutu Jr., Richard L. Johnson
Electrical and Computer Engineering Faculty Research and Publications
New methods to assemble, integrate, and package micro devices are always needed in attempts to simplify and expedite fabrication methods to maximize throughput. Our paper focuses on assessing SU-8 as a viable material for packaging and flip chip bonding processes for MEMS and micro devices. In this paper, we vary the level of cross- linking through post exposure bake (PEB) times and assess rectangular ring test structures bonding strength following flip chip bonding through applied tensile loads. In addition, we performed initial assessments on the etching resiliency of varied cross-linking of SU-8. From initial results, the bonding strength is maximized …
A Web And Mobile System For Environmental Decision Support, James Carswell, Keith Gardiner, Michela Bertolotto, Andrea Rizzine
A Web And Mobile System For Environmental Decision Support, James Carswell, Keith Gardiner, Michela Bertolotto, Andrea Rizzine
Books/Book chapters
Current field data collection methods for many of today’s scientific and other observer/monitor type applications are still entrenched in the “clipboard age”, requiring manual data transcription to a database management system at some (often much) later date, and only allows for visualisation and analysis of recently captured field data “back in the lab”. This chapter is targeted at progressing today’s pen & paper methodology into the spatially enabled mobile computing age of realtime multi-media data input, integration, visualisation, and analysis simultaneously both in the field and the lab. The system described is customized to the specific needs of the Canadian …
A Comparison Of Micro-Switch Analytic, Finite Element, And Experimental Results, Ronald A. Coutu Jr., P. E. Kladitis, Lavern A. Starman, J. R. Reid
A Comparison Of Micro-Switch Analytic, Finite Element, And Experimental Results, Ronald A. Coutu Jr., P. E. Kladitis, Lavern A. Starman, J. R. Reid
Electrical and Computer Engineering Faculty Research and Publications
Electrostatically actuated, metal contact, micro-switches depend on having adequate contact force to achieve desired, low contact resistance. In this study, higher contact forces resulted from overdriving cantilever beam style switches, after pull-in or initial contact, until the beam collapsed onto the drive or actuation electrode. The difference between initial contact and beam collapse was defined as the useful contact force range. Micro-switch pull-in voltage, collapse voltage, and contact force predictions, modeled analytically and with the CoventorWare finite element software package, were compared to experimental results. Contact resistance was modeled analytically using Maxwellian spreading resistance theory. Contact resistance and contact …