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.

Introducing the MiniBee

The MiniBee Rev.A circuit boardis a small, arduino-like circuit board I designed for the SenseStage project, a collaboration between the IDMIL and Chris Salter‘s lab at Concordia University. The boards include the footprint for a XBee mesh-networking wireless transceiver, creating compact, low-cost sensing nodes which we are now using for investigating ubiquitous computing in the media arts.

The first batch of 100 MiniBee Rev.A boards have been manufactured, assembled and tested 🙂

Good vibrations

As I mentioned earlier, I augmented one of the T-Sticks with a vibration motor designed by Hsin-Yun Yao and Vincent Hayward of McGill’s Haptics Lab. Since then, various incarnations of the T[actile]-Stick have been used for pursuing research at McGill on Enactive Interfaces. Recently I finished building a prototype with multidimensional vibration feedback: a wooden harness is used at each end to mount two linear vibration motors orthogonal to the length axis of the pipe. This allows stereo panning effects along the length of the pipe, and will hopefully lead to some more sophisticated haptic effects than I described in my initial project report.