The woofer-tweeter experiment

The Woofer-Tweeter experiment started in the Adaptive Optics Laboratory of the University of Victoria in February 2005 has recently achieved completion. The goal of this experiment is to validate the woofer-tweeter AO concept i.e. instead to have a single deformable mirror conjugated at the ground, two DMs conjugated at the ground are used to achieve both the necessary stroke and actuators density required for a single DM for an ELT. Recently, the loop has been closed on the turbulence with a loop rate of 100Hz. Two closed-loop controllers have been tested so far: a global integrator and a tweeter off-loading integrator. This paper describes the UVic Woofer-Tweeter bench layout and components and the Woofer-Tweeter simulation tool used to both model and control the experiment. A glimpse on the very first results from the closed-loop operations is also given.