We describe the design of a system of compact, wireless sensor modules meant to capture expressive motion whenworn at the wrists and ankles of a dancer. The sensors form ahigh-speed RF network geared toward real-time dataacquisition from multiple devices simultaneously, enabling asmall dance ensemble to become a collective interface formusic control. Each sensor node includes a 6-axis inertialmeasurement unit (IMU) comprised of three orthogonalgyroscopes and accelerometers in order to capture localdynamics, as well as a capacitive sensor to measure closerange node-to-node proximity. The nodes may also beaugmented with other digital or analog sensors. This paperdescribes application goals, presents the prototype hardwaredesign, introduces concepts for feature extraction andinterpretation, and discusses early test results.