Mechanical Structure and Propulsion
mechanical arrangement follows a modular approach,
with three main bodies linked by a light mechanical
structure, holding the structure together and hiding
interconnect cables. Each body is assembled with interchangeable
Horizontal propulsion and direction are controlled
by four independent thrusters
located at the stern.
Another set of thrusters, in the vertical
direction, control vertical velocity and pitch angle. A
single lateral thruster provides sway motion.
The thruster arrangement permits
operations in very confined areas, with virtually
independent horizontal, vertical, and lateral motion at velocities
starting at 0 m/s.
provided by rechargeable Li-Ion batteries
located in the lower pod, with a total
energy of 800 Wh.
Depending on vehicle velocity, these batteries can last
up to 10 hours, corresponding to about 40km.
computer is a PC-104 stack located in the upper
body, with a power supply, the CPU,
a communications board and a solid-state disk. The
navigation system is based on a LBL
acoustic network. The vehicle software continuously fuses
ranges to the acoustic beacons, together with compass heading,
inertial data and
thruster RPM to compute the estimated position.
When the vehicle surfaces, a GPS
receiver provides absolute position and communications
may be established using Wi-Fi or a UHF radio link.
spare cylindrical sections
to accommodate payload sensors,
such as video and sonars, and
it is simple to include further modules if required. All
end caps have spare connectors to provide energy
Larger payload sensors may also be attached to the
mechanical structure and buoyancy can be trimmed by
removing ballast weights or adding extra flotation.
Before vehicle launch, two acoustic beacons are deployed in the
operation area to provide a baseline for LBL navigation.
TriMARES missions may be programmed as
an AUV using a
GUI software, where all mission segments are detailed (waypoints,
velocity, depth, ...). During these missions, there is
no communication with the vehicle, although it is
possible to track the position through acoustics. Alternatively, the operator may
chose to connect the fiber optic umbilical to provide a high speed link for
realtime data transmission and, if required, to steer the
vehicle as an ROV.
TriMARES shipped to Brazil.
Full system validation in Douro river.
First trials in test tank, ROV and AUV operations.
Vehicle fully assembled.
Jan'11 - Computational systems
Dec'10 - Validation of
energy management module (lower pod).
Sep'10 - First mechanical parts
Aug'10 - Contract signed,
definition of main