Robotics Insights for the Modeling of Visually Guided Hand Movements in Primates
Résumé
In this chapter we focus on the modeling of cortical activity related to planning and control of visually guided reaching hand movements in primates. We bring a new light to this problem by considering the visual-servoing framework in robotics. A review of representative theories and models describing the neuronal processesrelated to 3D representation of space, motor control and visuomotor integration in Neuroscience is first presented. The kinematics and dynamics of manipulators and the basics of visual-servoing techniques in robotics are then recalled. In particular, for the control of a robotic arm with a deported camera, we underline the fact that the task-Jacobian is dependent on all the joints of the kinematic chain linking the camera to the end-effector. This point suggests that the motor activity during a visually guided movement of the hand cannot be completely encoded within a body-centered reference frame as claimed by numerous models in Neuroscience. Finally, we present an experimental result showing the existence of gaze-related signals in the monkey premotor cortex during visually guided reaching. This result corroborates the idea that the eye position with respect to the head and the head position with respect to the body, which belong to the kinematic chain linking the eye to the hand, must also be coded by neurons in premotor and motor cortex.