The Spine

The Spine is a “prosthetic” digital musical instrument developed for the collaborative project Les Gestes, in which we endeavoured to design new instruments for dancers.  The new instruments would extrapolate from the T-Stick, which we had already used in the performance Duo pour un violoncelle et un danseur with the same collaborators. Starting with foam prototypes, the Spine and its companion instruments the Rib and the Visor were developed iteratively using participatory design through frequent workshops, parallel problem solving, and digital fabrication methods. The current models are fabricated from laser-cut transparent acrylic, transparent PVC tubing, and PETg rods. The entire structure is assembled using interference fitting rather than any glues or fasteners.

The Spine tracks and reports it’s orientation and shape in real-time, accomplished through the use of inertial and magnetic-field sensing at each end of the structure. Sensor-fusion algorithms run on-board the instrument.

I have previously blogged some teaser photos and a couple of videos showing a demonstration of the orientation and deformation sensing I developed for the Spine and a promo for the upcoming shows.

Using multiple IMUs for sensing deformation

I made this video today to quickly document some work I’ve been doing using multiple inertial measurement units (IMUs) for tracking the orientation, bending, and twisting of deformable objects. Intertial measurement units generally contain 3-axis accelerometers, gyroscopes, and magnetometers – the data can be cleverly combined to obtain an estimate of orientation (as long as the IMU is being used in an environment with constant gravity and magnetic field, and not in free-fall).

This particular object has two Mongoose IMUs embedded inside it, running some custom firmware I wrote for complementary filtering/sensor fusion for estimation of orientation.