This paper describes a complete system for the specification and the generation of communication gestures. A high level language for the specification of hand-arm communication gestures has been developed. This language is based both on a discrete description of space, and on a movement decomposition inspired from sign language gestures. Communication gestures are represented through symbolic commands which can be described by qualitative data, and traduced in terms of spatiotemporal targets driving a generation system. Such an approach is possible for the class of generation models controlled through key-points information. The generation model used in our approach is composed of a set of sensory-motor servo-loops. Each of these models resolves in real time the inversion of the servo-loop, from the direct specification of location targets, while satisfying psycho-motor laws of biological movement. The whole control system is applied to the synthesis, and a validation of the synthesized movements is presented.