1. INTRODUCTION
The oceanic research is gaining interests in autonomous
underwater gliders because of their reliability, low-power
consumption, high endurance and long distance skill. In
fact, the satellite navigation and communication made
possible the advent of small inexpensive autonomous underwater
gliders (AUGs) that can observe the ocean in
place of the humans and provide high quality and high
density information. AUGs use a buoyancy engine to move
following a sawtooth path where satellite navigation and
communication are carried out at the surface. The considered
vehicles are highly nonlinear and the feasible control
actions are constrained.