  The design and application of an instrumented particle for the lagrangian
characterization of turbulent free surface flows is presented in this study.
This instrumented particle constitutes a local measurement device capable of
measuring both its instantaneous 3D translational acceleration and angular
velocity components, as well as recording them on an embarked removeable memory
card. A lithium ion polymer battery provides the instrumented particle with up
to 8 hours of autonomous operation. Entirely composed of commercial off the
shelf electronic components, it features accelerometer and gyroscope sensors
with a resolution of 16 bits for each individual axis, and maximum data
acquisition rates of 1 and 8 kHz, respectively, as well as several user
programmable dynamic ranges. Its ABS 3D printed body takes the form of a 36 mm
diameter hollow sphere, and has a total mass of (19.6 $\pm$ 0.5) g. Controlled
experiments, carried out to calibrate and validate its performance showed good
agreement when compared to reference techniques. In order to assess the
practicality of the instrumented particle, we apply it to the statistical
characterization of floater dynamics in experiments of surface wave turbulence.
In this feasibility study, we focused our attention on the distribution of
acceleration and angular velocity fluctuations as a function of the forcing
intensity. The IP's motion is also simultaneously registered by a 3D particle
tracking velocimetry (PTV) system, for the purposes of comparison. Beyond the
results particular to this study case, it constitutes a proof of both the
feasibility and potentiality of the IP as a tool for the experimental
characterization of particle dynamics in such flows.
