Linear Control Design for a Path Planning of Auv-cor- Moran

This work shows a linearization for a AUV-Cormoran dynamic mathematical model with the aim of designing linear controllers for trajectory control. The model is developed under 3 degrees of freedom and the whole system has been simulated in Matlab Simulink environment. The linearization model is based on understanding the dynamics of the vehicle under different operating speeds, which present a different behavior, yet to be controlled by a single linear controller. For the linear control has raised the PD control that allows eliminate the position error, performing simulations of different trajectories and comparing its results in stability. Introduction The Cormoran is a low-cost vehicle for ocean observing, is a hybrid of the AUV (Autonomous Underwater Vehicles) and ASV (Autonomous Surface Vehicles) which was built in the Mediterranean Institute of Advanced Studies (IMEDEA), from Mallorca (Spain), for a group of Oceanography, in collaboration with the University of the Balearic Islands. Figure 1 shows a picture of the vehicle. The vehicle was designed to sail just below the water surface along a predetermined path following way-points, in which it sinks vertically and obtains samples of the water column. Then it emerges also vertically and transmits by GSM messages with the most relevant data (temperature, salinity, depth and position, given by a GPS on board). Afterwards, it moves to a new way-point repeating the process, and so on until a mission is completed [1]. Vehicle Model in 3DOF Due to the movements of the vehicle described above, the heave, roll and pitch can be neglected, so that the characterization of the vehicle can be achieved through a 3-DOF model for the advance ( ), lateral movement ( ) and yaw angle ( ) [2]. Vectors position, speed and strength can be expressed as shown in (2.1). Figure 1. AUV Cormoran II-A. Vehicle Dynamics Equation (2.2) is the nonlinear dynamic equation of an underwater vehicle, (2,1)