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Description
TolTEC is a three-band millimeter-wave, imaging polarimeter installed on the 50 m diameter Large Millimeter Telescope (LMT) in Mexico. This camera simultaneously images the focal plane at three wavebands centered at 1.1 mm (270 GHz), 1.4 mm (214 GHz), and 2.0 mm (150 GHz). TolTEC combines polarization-sensitive kinetic inductance detectors

TolTEC is a three-band millimeter-wave, imaging polarimeter installed on the 50 m diameter Large Millimeter Telescope (LMT) in Mexico. This camera simultaneously images the focal plane at three wavebands centered at 1.1 mm (270 GHz), 1.4 mm (214 GHz), and 2.0 mm (150 GHz). TolTEC combines polarization-sensitive kinetic inductance detectors (KIDs) with the LMT to produce high resolution images of the sky in both total intensity and polarization. I present an overview of the TolTEC camera’s optical system and my contributions to the optomechanical design and characterization of the instrument. As part of my work with TolTEC, I designed the mounting structures for the cold optics within the cryostat accounting for thermal contraction to ensure the silicon lenses do not fracture when cooled. I also designed the large warm optics that re-image the light from the telescope, requiring me to perform static and vibration analyses to ensure the mounts correctly supported the mirrors. I discuss the various methods used to align the optics and the cryostat in the telescope. I discuss the Zemax optical model of TolTEC and compare it with measurements of the instrument to help with characterization. Finally, I present the results of stacking galaxies on data from the Atacama Cosmology Telescope (ACT) to measure the Sunyaev-Zel’dovich (SZ) effect and estimate the thermal energy in the gas around high red-shift, quiescent galaxies as an example of science that could be done with TolTEC data. Since the camera combines high angular resolution with images at three wavelengths near distinct SZ features, TolTEC will provide precise measurements to learn more about these types of galaxies.
ContributorsLunde, Emily Louise (Author) / Mauskopf, Philip (Thesis advisor) / Groppi, Christopher (Committee member) / Scannapieco, Evan (Committee member) / Noble, Allison (Committee member) / Bryan, Sean (Committee member) / Arizona State University (Publisher)
Created2023
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Description
Walking and mobility are essential aspects of our daily lives, enabling us to engage in various activities. Gait disorders and impaired mobility are widespread challenges faced by older adults and people with neurological injuries, as these conditions can significantly impact their quality of life, leading to a loss of independence

Walking and mobility are essential aspects of our daily lives, enabling us to engage in various activities. Gait disorders and impaired mobility are widespread challenges faced by older adults and people with neurological injuries, as these conditions can significantly impact their quality of life, leading to a loss of independence and an increased risk of mortality. In response to these challenges, rehabilitation, and assistive robotics have emerged as promising alternatives to conventional gait therapy, offering potential solutions that are less labor-intensive and costly. Despite numerous advances in wearable lower-limb robotics, their current applicability remains confined to laboratory settings. To expand their utility to broader gait impairments and daily living conditions, there is a pressing need for more intelligent robot controllers. In this dissertation, these challenges are tackled from two perspectives: First, to improve the robot's understanding of human motion and intentions which is crucial for assistive robot control, a robust human locomotion estimation technique is presented, focusing on measuring trunk motion. Employing an invariant extended Kalman filtering method that takes sensor misplacement into account, improved convergence properties over the existing methods for different locomotion modes are shown. Secondly, to enhance safe and effective robot-aided gait training, this dissertation proposes to directly learn from physical therapists' demonstrations of manual gait assistance in post-stroke rehabilitation. Lower-limb kinematics of patients and assistive force applied by therapists to the patient's leg are measured using a wearable sensing system which includes a custom-made force sensing array. The collected data is then used to characterize a therapist's strategies. Preliminary analysis indicates that knee extension and weight-shifting play pivotal roles in shaping a therapist's assistance strategies, which are then incorporated into a virtual impedance model that effectively captures high-level therapist behaviors throughout a complete training session. Furthermore, to introduce safety constraints in the design of such controllers, a safety-critical learning framework is explored through theoretical analysis and simulations. A safety filter incorporating an online iterative learning component is introduced to bring robust safety guarantees for gait robotic assistance and training, addressing challenges such as stochasticity and the absence of a known prior dynamic model.
ContributorsRezayat Sorkhabadi, Seyed Mostafa (Author) / Zhang, Wenlong (Thesis advisor) / Berman, Spring (Committee member) / Lee, Hyunglae (Committee member) / Marvi, Hamid (Committee member) / Sugar, Thomas (Committee member) / Arizona State University (Publisher)
Created2023
ContributorsHodjati, Katayoon (Performer) / Chae, Eunkyoung (Performer) / Dunger, Rob (Performer) / Gordon, Matt (Performer) / Ryan-Kelzenberg, Matthew (Performer) / ASU Library. Music Library (Publisher)
Created2004-10-01
ContributorsHoover, Eric (Performer) / Spinosa, Frank, 1930- (Performer) / Magers, William (Performer) / Atsumi, Takayori (Performer) / Barroll, Rayna (Performer) / Meyer, Janice (Performer) / May, Judy (Performer) / Cosand, Walter, 1950- (Performer) / Britton, Mervin (Performer) / ASU Library. Music Library (Publisher)
Created1986-10-13
ContributorsDauphinais, Michael (Performer) / George, Clara (Performer) / Helms, Katherine (Performer) / Tout, Rebecca (Performer) / Cain, Rebecca (Performer) / Layton, Spencer (Performer) / Adkins, Bryan (Performer) / Egle, Eric (Performer) / Clark, Mai (Performer) / ASU Library. Music Library (Publisher)
Created2000-03-08
ContributorsPeterson, Trygve (Performer) / Schuring, Martin (Performer) / Spring, Robert (Performer) / Wytko, Joseph (Performer) / Smith, J. B., 1957- (Performer) / Cosand, Walter, 1950- (Performer) / Hakes, Roy (Performer) / Novak, Gail (Pianist) (Performer) / ASU Library. Music Library (Publisher)
Created1994-11-06
ContributorsHackbarth, Glenn, 1949- (Performer) / Wytko, Joseph (Performer) / New Music Ensemble (Performer) / ASU Library. Music Library (Publisher)
Created1979-12-09
ContributorsPagano, Caio, 1940- (Performer) / Granjon, Jerome (Performer) / Branch, Sonja (Performer) / Nottingham, Douglas (Performer) / ASU Library. Music Library (Publisher)
Created2003-10-31
ContributorsSpinosa, Frank, 1930- (Performer) / Mutschler, Marla (Performer) / Magers, William (Performer) / Atsumi, Takayori (Performer) / Sellheim, Judy May (Performer) / Wytko, Joseph (Performer) / Montgomery, Toni-Marie (Performer) / Metz, John (Performer) / Williamson, Madeline J. (Performer) / Koonce, Frank (Performer) / Spring, Robert (Performer) / Hoover, Eric (Performer) / Patnode, Matthew (Performer) / LaMonica, Michael (Performer) / Anthony, Jeffrey (Performer) / New Art String Quartet (Performer) / Joseph Wytko Saxophone Quartet (Performer) / ASU Library. Music Library (Publisher)
Created1992-10-06
ContributorsGolden, Samuel (Performer) / Harkey, Noah (Performer) / Harkey, Emma (Performer) / Staebell, Justin (Performer) / Bivona, Kate (Performer) / Doike, Asia (Performer) / Hodgson, Ria (Performer) / Henley, Evan (Performer) / Nix, Katie (Performer) / Lang, Jon (Performer) / Stanton, Grayson (Performer) / Siegfried, Jeff (Performer) / ASU Library. Music Library (Publisher)
Created2011-03-26