Abstract
The ability to employ autonomous vehicles to find and track the boundary between two different water masses can increase the efficiency in waterborne data collection, by concentrating measurements in the most relevant regions and capturing detailed spacial and temporal variations. In this paper we provide a guidance mechanism to enable an autonomous vehicle to find and track the steepest gradient of a scalar field in the horizontal plane. The main innovation in our approach is the mechanism to adapt the orientation of the crossings to the local curvature of the boundary, so that the vehicle can keep tracking the gradient regardless of its horizontal orientation. As an example, we show how the algorithms can be used to find and track the boundary of a dredged navigation channel, using only altimeter measurements.

Abstract
In this article we describe the implementation of remote monitoring and control for multiple and independent experiments, namely, ecosystem replication experiments. First by presenting the main concepts behind the system architecture, and ultimately its design, and secondly by discussing its implementation. The system makes use of IEEE 802.15.4 Standard for Wireless Communications, a BeagleBone Black as the central coordinator for the experiments, and Arduino Mega as the monitoring and control device for each experiment. Data is stored on a PostgreSQL RDBMS, and the user interfaces with the system through a Website.

Abstract
Aquaculture processes usually take place in remote and harsh environments, and are highly dependent on uncontrollable and unpredictable variables, therefore its monitoring and supervision can be a key factor in this activity. Taking that into account, this paper proposes a solution for a Remote Supervision System for Aquaculture Platforms, that contemplates a modular, reconfigurable and expandable sensor network based on the I2C protocol, which is composed by two different types of sensor nodes. The main sensor node, which serves as the sensor network coordinator and as a gateway, and the tiny sensor nodes, that are responsible for simple data collection tasks.

Abstract
Underwater sensing and mapping operations using autonomous vehicles are becoming widely used. This article describes an automated system to launch and recover an AUV. It can operate in any host platform and can transport any torpedo-shaped vehicle with 0.2 meters of diameter, length up to 3 meters and weight up to 1000 N. The system ensures a restrained transportation of the vehicle and guarantees that it performs a smooth entrance in the water. It was instrumented for continuous status remote monitoring, using linear and angular motion sensors, as well as enables to remotely take control over the operation. Experimental results carried out within the XPRIZE competition demonstration scope are presented.

Abstract
This paper presents an overview of a generalized 6 degrees of freedom model for surface vessels and explains how it can be extended for twin hull surface vehicles. The extended model takes into account the hull characteristics (dimensions and location), which are important to improve the accuracy of simulations and the performance of controllers. The method involves the calculation of the submerged volume of each hull, location of each hull's center of buoyancy and restoring forces/ torques due to buoyancy contributions. To evaluate the proposed model, some simulations were performed, using an example of allocation of propulsion system and realistic hydrodynamic coefficients (added mass and damping) and inertial tensors.

Abstract
This paper describes the PISCES system, an integrated approach for fully autonomous mapping of large areas of the ocean in deep waters. A deep water AUV will use an acoustic navigation system to compute is position with bounded error. The range limitation will be overcome by a moving baseline scheme, with the acoustic sources installed in robotic surface vessels with previously combined trajectories. In order to save power, all systems will have synchronized clocks and implement the One Way Travel Time scheme. The mapping system will be a combination of an off-the-shelf MBES with a new long range bathymetry system, with a source on a moving surface vessel and the receivers on board the AUV. The system is being prepared to participate in round one of the XPRIZE challenge.