MetaMuse : using metaphor to design and play expressive instruments

• Main Author: Gadd, Ashley
• Format: Others
• Language: English
• Published: 2009
• Online Access: http://hdl.handle.net/2429/16277

This thesis provides a framework for understanding and predicting the expressive nature of devices. We introduce transparency, or the ease with which a device's mapping can be understood, as the main pillar of this framework. Transparency is a predictor for expressivity, the ease with which meaning or emotion can be communicated through the device. We explore the role of metaphor for improving the amount of expression possible with a device, and examine its use as both a design aid and an affordance during use. To validate this theory we built MetaMuse, a controller for a rain-sound synthesiser that employs water metaphors to obviate its use. MetaMuse uses physical props to embody three metaphors: pouring, rainfall, and landscape. These metaphors acted as a guide during MetaMuse's design, and aid users in the prediction of system operation and sound output. We performed a series of experiments comparing MetaMuse to two other interfaces to test our claim that metaphor can be used to improve expressivity. The tests measured controllability with speed and accuracy of sound target acquisition, and expressivity with qualities such as creativity. Accuracy was similar across all interfaces, and speed slightly improved for MetaMuse, but the controllability results lacked significance. Results for expressivity were significant, however: users preferred MetaMuse as more creative than two more traditional controllers (F=6.0, p<0.01). From these results we conclude that metaphor is a worthy design approach to creating expressive devices. This thesis also presents a novel form of synthesis combining techniques from real-time stochastic synthesis and granular synthesis. Finally, it includes a software library for simplifying the use of the Polhemus Fastrak magnetic sensor used in the project. === Applied Science, Faculty of === Electrical and Computer Engineering, Department of === Graduate