Variable Recruitment in Bundles of Miniature Pneumatic Artificial Muscles and Space Qualified Pneumatic Artificial Muscles

The natural compliance and force generation properties of pneumatic artificial muscles (PAMs) allow them to operate like human muscles in anthropomorphic robotic manipulators. Traditionally, manipulators use a single PAM or multiple PAMs actuated in unison in place of a human muscle. However, these manipulators experience efficiency losses when operated outside their target performance ranges. The unidirectional actuation behavior of a miniature PAM bundle and bidirectional actuation behavior of an antagonistic pair of miniature PAM bundles are characterized and modeled. The results are used to motivate the application of a variable recruitment control strategy to a parallel bundle of miniature PAMs as an attempt to mimic the selective recruitment of motor units in a human muscle to improve the operating efficiency of the actuator. Additionally, the fabrication and quasi-static testing results for PAMs assembled from candidate space qualified bladder and braided sleeve materials for use in space robotics are assessed.

Nurturing Change: Lilly Martin Spencer's Images of Children

This dissertation is the first full-length study to concentrate on American genre painter Lilly Martin Spencer's images of children, which constituted nearly one half of her saleable production during the height of her artistic career from 1848 to 1869. At this time, many young parents received advice regarding child rearing through books and other publications, having moved away from their families of origin in search of employment. These literatures, which gained in popularity from the 1830s onward, focused on spiritual, emotional, and disciplinary matters. My study considers four major themes from the period's writing on child nurture that changed over time, including depravity and innocence, parent/child bonding, standards of behavior and moral rectitude, and children's influence on adults. It demonstrates how Spencer's paintings, prints, and drawings featuring children supported and challenged these evolving ideologies, helping to shed light not only on the artist's reception of child-rearing advice, but also on its possible impact on her middle-class audience, to whom she closely catered. In four chapters, I investigate Spencer's images of sleeping children as visual equivalents of contemporary consolation literature during a time of high infant and child mortality rates; her paintings of parent/child interaction as promoting separation from mothers and emotional bonding with fathers; her prints of mischievous children as both considering changing ideals about children's behavior and comforting Anglo-American citizens afraid of what they saw as threatening minority groups; and her pictures with Civil War and Reconstruction subject matter as contending with the popular concept of the moral utility of children. By framing my interpretations of Spencer's output around key issues in the period's dynamic child-nurture literature, I advance new comprehensive readings of many of her most well-known paintings, including Domestic Happiness, Fi, Fo, Fum!, and The Pic Nic or the Fourth of July. I also consider work often overlooked by other art historians, but which received acclaim in Spencer's own time, including the lithographs of children made after her designs, and the allegorical painting Truth Unveiling Falsehood. Significantly, I provide the first in-depth analysis of a newly rediscovered Reconstruction-era painting, The Home of the Red, White, and Blue.

THE COMPLETE PRELUDES OF ALEXANDER SCRIABIN: THE EVOLUTION OF HIS REVOLUTIONARY COMPOSITIONAL STYLE

During the second half of the nineteenth century, a series of remarkable advances in musical composition emerged in the works of such innovative spirits as Franz Liszt, Hector Berlioz and Richard Wagner. Their pioneering works exerted an extraordinary impact on the music of the subsequent generation of composers--of disparate nationalities-who were active at the dawn of the 20th century: Including most notably Claude-Achille Debussy, Gustav Mahler, Richard Strauss, and Alexander Nikolayevich Scriabin. These important musical figures, each one leaving an indelible and formative imprint on late-nineteenth century Romantic style, together launched the modern era in music. Scriabin stands alone as a transcendental visionary: His music, initiated in the fashion of Chopin and Liszt, wanders through the realms of Debussy and Wagner, and, ultimately abandoning late Romantic tradition, unlocks the heretofore unforeseen power of atonality, bitonality, polyrhythms and key-signature free compositions. Arguably, Scriabin's compositions count among the most innovative, idiosyncratic and bewitching of all time. The development of Scriabin's groundbreaking compositional style is best understood by means of his piano works, which comprise the majority of his oeuvre. Beyond the larger works-his twelve sonatas, a concerto and a fantasy-Scriabin's piano explorations are also represented by miniature gems: The mazurkas, impromptus, waltzes, poems, a polonaise, etudes, nocturnes, morceaux and, in particular, the preludes. Scriabin's 90 preludes for piano, arranged in several opus numbers, richly exemplify the striking evolution of his ingenious music, his idiosyncratic philosophy and his provocative personality.