In this work, a human performer interacts with the musical robots designed and built by WPI’s Music, Perception and Robotics Lab and Expressive Machines Musical Instruments. Musical interactions can occur in a variety of forms. The agents in an improvisation are typically able to sense the utterances of others, and are free to respond (depending on the constraints of the particular situation). The expressivity of an agent then is conveyed in a multitude of ways (pitch and rhythmic choices, timbral nuance, physical gestures, etc.). This kind of interaction has been a primary focus of my compositional work. Experiment in Augmentation 2 shows another kind of interaction that finds a human in greater control of the situation. The robots do not sense or interpret their sonic environment. Instead, they respond to human-produced cues by voicing one of a variety of pre-composed gestures (which may also be changed in the context of the performance). This configuration affects the way in which the robots are expressive. Their performative idiosyncrasies generate timbral, pitch and rhythmic variations, transforming the idealized pitch, rhythm and velocity instructions into new kind of statements (transformation is an important part of expressivity). As an ensemble, these gestures combine to create emergent textures that illuminate the novel expressive possibilities of machines. All of this inspires the human performer’s choices about which cue will come next. It shows the compositional process unfolding in real time, highlighting a way in which a human performer’s expressive abilities can be augmented via physical computing technologies.
