Jim W. Murphy

The machine orchestra: An ensemble of human laptop performers and robotic musical instruments

This article introduces the Machine Orchestra, a mixed ensemble of human and robotic performers. The Orchestra is coordinated through technical and musical classes at the California Institute of the Arts (CalArts), where the pedagogical focus is to combine the musical elements of a laptop orchestra with the technical skills required to create a robotic ensemble. As of this publication, seven electromechanical instruments have been developed by members and collaborators of the Orchestra. The ensemble has given notable international premieres and performances at venues including the Roy and Edna Disney/CalArts Theater (REDCAT) in Los Angeles and 01SJ, the biennial music and arts festival in San Jose, California. Well-known researchers and performers are invited to participate in the Orchestra to bring novel technical, musical, and collaborative ideas to the ensemble. In this article we describe the design and production of seven robotic instruments, details on the visual and sonic aesthetic of the ensemble, technical considerations of the computer network employed in performance, and information on an assortment of compositions in the current repertoire.

Musical Robotics in a Loudspeaker World: Developments in Alternative Approaches to Localization and Spatialization

ABSTRACT Musical robotics is a rapidly growing field, with dozens of new works appearing in the past half decade. This paper explores the foundations of the discipline and how, due to the ability of musical robots to serve as uniquely spatialized musical agents, it experienced a rebirth even in the face of loudspeaker technologys dominance. The growth of musical robotics is traced from its pre-computer roots through its 1970s renaissance and to contemporary installation-oriented sculptures and performance-oriented works. Major figures in the field are examined, including those who in recent years have introduced the world to human/musical robot interaction in a concert setting. The paper closes with a brief speculation on the fields future, with a focus on the increasing ease with which new artists may enter the field.

Expressive robotic guitars: Developments in musical robotics for chordophones

This article provides a history of robotic guitars and bass guitars as well as a discussion of the design, construction, and evaluation of two new robotic chordophones, with a focus on different techniques to extend the expressivity of robotic guitars. Swivel and MechBass, two new robots we built, are discussed. Construction techniques likely to interest other musical roboticists are included. These robots use a variety of techniques, both new and inspired by prior work, to afford composers and performers the ability to precisely control pitch and string-picking parameters. Both new robots are evaluated to test their precision, repeatability, and speed. The article closes with a discussion of the compositional and performative implications of such levels of control, and how it might affect humans who wish to interface with the systems.

An overview of MechBass: A four string robotic bass guitar

Traditional robotic guitar-like stringed instruments have lacked sufficient degrees of freedom and responsivity required to emulate even an average human guitar player. We seek to address this in the design and construction of a modular four-string robotic bass guitar, MechBass. This paper describes the various components of each module and the system-level operation of MechBass. The result is an instrument that can outperform (in terms of capability and consistency) even a highly skilled human guitar player.

A comparative evaluation of percussion mechanisms for musical robotics applications

This paper presents a summary of several of the various types of percussion mechanisms commonly utilized in the field of musical robotics, with a goal of comparing their effectiveness regarding a number of musical outcomes. A testing system was set up to compare the devices and analyze a number of relevant attributes of their performance, such as maximum speed and volume, consistency and latency. The advantages and disadvantages of each of the types of mechanisms are discussed, and suggestions are offered about which types of mechanisms are suitable for various musical contexts.

Loudspeakers Optional: A history of non-loudspeaker-based electroacoustic music

The discipline of electroacoustic music is most commonly associated with acousmatic musical forms such as tape-music and musique concrete, and the electroacoustic historical canon primarily centres around the mid-twentieth-century works of Pierre Schaeffer, Karlheinz Stockhausen, John Cage and related artists. As the march of technology progressed in the latter half of the twentieth century, alternative technologies opened up new areas within the electroacoustic discipline such as computer music, hyper-instrument performance and live electronic performance. In addition, the areas of electromagnetic actuation and musical robotics also allowed electroacoustic artists to actualise their works with real-world acoustic sound-objects instead of or along side loudspeakers. While these works owe much to the oft-cited pioneers mentioned above, there exists another equally significant alternative history of artists who utilised electric, electronic, pneumatic, hydraulic and other sources of power to create what is essentially electroacoustic music without loudspeakers. This article uncovers this ‘missing history’ and traces it to its earliest roots over a thousand years ago to shed light on often-neglected technological and artistic developments that have shaped and continue to shape electronic music today.

Transcoding Nancarrow at the Dawn of the Age of MIDI: The Preservation and Use of Conlon Nancarrow’s Player Piano Studies

This article focuses on the process by which, in 1987, sound artist and inventor Trimpin converted composer Conlon Nancarrow’s Studies for Player Piano from their original hand-punched rolls into the MIDI format. In addition to presenting the technology utilized in this conversion, the article focuses on the collaboration between Trimpin and Nancarrow, and on the significance of the act of porting works composed upon a vulnerable media format to a format that affords extension, analysis and preservation. The article concludes with an overview of a number of example uses of the transcoded Nancarrow scores, including traditional performances and two extended performances and installations.

An Inclusive Musical Mechatronics Course

This paper presents the design of a novel course in mechatronics, based on a project-based learning pedagogical philosophy that uses music as the theme to introduce to a diverse range of learners, the essential concepts of mechatronic practice. The course is designed at a post-graduate level and is targeted at international students who are likely to have a diverse range of background knowledge and potentially even a greater diversity in practical experience. The course builds upon our knowledge and capability in the construction or instrumentation of musical devices and cumulates in the construction of a new mechatronic chordophone and the preparation of an IEEE conference paper submission.