Eye-centered vs body-centered reaching control: A robotics insight into the neuroscience debate

Whether the central nervous system of primates uses a body-centered or an eye-centered frame for reaching is still a controversial debate in neurosciences. Does the proprioceptive information allow to represent the visual information with respect to the body or inversely, does it transform the hand position in retinal coordinates? In this paper, we implement and test two control schemes associated to each of these two hypotheses by using a computational approach from robotics. To this end, biological models of motor control are applied to a realistic dynamic model of upper body including a 4 DOF eye-neck kinematic chain and a 6DOF arm. Important characteristics, such as proprioceptive biases and sensory delay, are considered. Simulation results allow to compare the geometry of trajectories and illustrate the better robustness of the eye-centered control scheme with respect to biases and sensory delay. Applications to the control of the humanoid robot HRP2 are finally presented.