Zyggie is a motion capture platform design within the labex Cominlabs Bowi project. It consists of a set of electronic components (nodes) arranged on a part or the whole body of a person.
- The Inertial Measurement Unit (IMU) embedded in these nodes can duplicate the movement on an avatar moving on an Android tablet.
- Communication between nodes is performed by radio and extensive energy optimization allows them an operating autonomy of 20 hours.
- As recharging nodes batteries also occurs wirelessly, it is therefore possible (even if this is not the case for current prototypes) to embed them in a waterproof box.
This state-of-the-art platform has enabled to thoroughly analyze BAN sensor network related challenges dedicated to motion capture. Our work focused primarily on opportunities to dispense with the energy intensive gyroscope, using radio power information received by the sensor network.
The applications are animation, functional rehabilitation, optimization of sports movements, robotics, non-verbal communication in fighting situations.
A second version of this system was developed with an UWB transceiver, a quality improvement of IMU sensing and a micro USB port. The UWB chip allows to perform ranging measurements between Zyggie systems for user localization (extra-BAN) and sensors 3D positionning in space (intra-BAN). A data fusion algorithm with IMU and UWB distances can be used for accuracy improvement of user’s movement processing.
A communication protocol based on IEEE 802.15.4 was implemented to sequence measure and communication phases with the aim of optimizing system energy consumption.