Signal-dependent noise

…based on optimal feedback control with signal-dependent noise (Todorov, 2005) have been able to account for many phenomena including online corrections, redundancy, synergies, and uncontrolled manifolds of movements. In past research, a cost function needed to be assumed for the respective task, and agreement between the predictions of optimal behavior by the model and empirical movement trajectories had to be assessed. However, not all behavioral goals may be known a priori and costs internal to the subject such as biomechanical or subje

Human eye movements are controlled by six extraocular muscles. Although the eye socket restricts eye movements to almost pure rotations (3 degrees-of-freedom) the brain seems to control it using only 2 degrees of freedom, keeping the torsional component in a strict relationship with the gaze angles (azimuth and elevation), according to Donders’ Law (Tweed et al.,1987). To study the control principles that may lead to such behaviour, we have designed a scaled-up cable-driven robotic eye with six actuators, with cable insertion points closely matching the relative positions of its biological cou