P068

The Underwater Vehicle MAUVE :An User-Friendly Tool for Coastal Survey

A0170 Maria-Joao Rendas Laboratoire d'Infomatique, Signaux et Systemes de Sophia Antipolis (13S)

A0171 Yoan Hebrad Laboratoire d'Infomatique, Signaux et Systemes de Sophia Antipolis (13S)

We present the miniaturized autonomous underwater vehicle MAUVE, which

is the result of a joint effort of several European partners in the

context of two EU-funded projects. This vehicle is targeted for the

surveying and mapping of coastal areas:it is light (about 30 Kg in the

air) and small (less than 2 meters long and 15 cm diameter), allowing

launching and recovering by a single person from a small boat,

minimizing in this way the logistics associated to its operation. A

special attention has been given to the design of the user interface

of the vehicle, which has been conceived with the community of final

end-users (biologists, oceanographers,) in mind:simple graphic input

of the mission definition, wide variety of possible formats for site-

specific information, availability of simulation tools for pre-mission

validation, and automatic choice of vehicle-related parameters from

the high-level user definition of the mission. For

development/upgrading purposes, the interface contains a completely

separated "programmers level "which provides the necessary interface

for engineering developments.

In the paper, we present an overview of the vehicle (physical and

energetic characteristics, sensor suites, hardware architecture,

software architecture) focusing on the presentation of its man-machine

interface.The user level offers eight main menus:project, robot, site,

externals, mission, simulation, download and upload. The project menu

allows the user to re-open an existing project, create a new one, or

save the current project under a different name. This facility is

useful when repeating several sea-trials in the same area, keeping a

complete and structured record of the individual experiments performed.

Mauve is a re- configurable AUV, with alternative payload sections

which can be easily inter-changed. For this reason, the robot menu

allows the user to indicate which sensors are effectively mounted on

the platform. The site menu gathers information about the mission

region, and accepts different kinds of information, ranging from a

simple scanned marine map (image), in which case the user will be

asked to click on three points of the image indicating their

geographical coordinates, to numerical bathymetry maps (geographical

coordinates or UMT coordinates) and, eventually, current maps on the

mission site. The available information is displayed in a "mission

window ". If no maps are available, the user can work with an empty

"mission window ", by assigning a coordinate system to it (by mouse

clicking on three points). These three menus must be completed before

the user can access the other menus of the interface.The external menu

is used to enter the estimated launching point and the desired

recovery (homing) point, as well as the alowable tolerance on homing

precision. The user is also asked in this menu to indicate the

location of the two acoustic beacons that must be installed in the

area for global positioning of the platform. The mission menu is

indeed the place where the user specifies the tasks that he wishes the

robot to perform. The mission consists of a chain of tasks, each with

an entry point and an existing point. The order by which the

individual tasks are performed can be easily interchanged (my click-

and-drag). The interface automatically inserts the joining segments,

facilitating redefinition of the tasks ordering. The user can select

from a series of pre-defined basic tasks: simple go-to-point; visit a

sequence of way-points; sample a given polygonal region (at a given

depth, with a given spatial sampling rate), sample a 3D volume;track a

given sensor condition during a certain distance. This set of basic

missions has been designed for the specific needs of the two EU-

projects demonstrations. However, the modular design of the real-time

architecture around the same set of basic tasks, allows the easy

definition of new ones both in the interface and on the on-board

software.

The simulate menu (which is enabled only when a mission has been

defined) allows the execution of a complete simulation of the mission,

using a dynamic model of the vehicle, enabling early detection of

possible problems (for instance a bad behaviour with respect to

currents, large positioning errors due to a bad choice of the position

of the acoustic beacons). Finally, the download menu assists the user

in the phase of powering-up, down-loading (through a serial link) of

the mission to the actual platform, and actual vehicle launching. It

also instructs the user to use the upload menu upon mission completion

to recover the data gathered by the robot.

The upload menu gives access to two main tools: one that guides the

vehicle during data recovery, creating files in the log directory of

the project with the data recovered from the vehicle memory, and

visualisation tools that enable the graphic display of the information

contained in these files (estimated on-board trajectory, bathymetry

maps, depth profiles along mission,).

Throughout the paper, we illustrate the utilisation of this interface

using real projects corresponding to at-sea trials of Mauve, providing

in this way a comprehensive illustration of the capabilities of this

small, affordable and easy to operate vehicle. We conclude the paper

by describing the new upgrades under current development.

 

MAUVE, MAST III Project (1996/98), partners:CNIM (Fr)Thomson (Fr), GMI

(Dn), IST (Pt), CNR (It), Ifremer (Fr), I3S (Fr), MUMM (Be);and SUMARE,

IST project (2000/2002), partners: I3S (Fr), Thomson (Fr), IST (Pt),

MUMM (Be)and HWU (UK). http://www.mumm.ac.be/SUMARE.