42 st / May 2016 www.sea-technology.com
separating into two boxes the
control-related and payload
electronics. All of the control
software, developed by embed-
ded software and robotics ex-
perts at ISME, is on a rather sim-
ple CPU and microcontroller,
always in charge of command-
ing the thrusters, communicat-
ing with the navigation sensors
and sending the telemetry to
the remote ground control sta-
tion. A separate box can hold
another CPU, dedicated to the
acquisition of the scientifc sen-
sors, without risk of interfering
with the control software. Fur-
thermore, a payload box can be
developed for a specifc group of sensors, and whenever the
drones must be reconfgured with another set of sensors, the
payload box can simply be substituted with another one de-
veloped for the second set, greatly decreasing the required
reconfguration time and costs.
Detailed Characteristics of the USVs
The developed USVs are 2-m long and 1.5-m wide,
weighing 115 kg without payload, and have a draft of 0.44
m at 140 kg, making them easily employed in very shallow
waters. The USVs have around 35 kg dedicated to possible
payloads. The two motors have a thrust of 13 kgf in both di-
rections. Due to their differential propulsion, the USVs can
poses. All of the electronics are housed within waterproof
boxes placed on the main deck of the catamarans, another
design choice to simplify the use of the drones. This allows
for foam inside the hulls, increasing the strength of the boats
and simplifying the access to all the electronics, since there
is no need to remove screws to access electronics inside the
hulls. Rather, the boxes on the deck can be easily accessed
and opened. Furthermore, this solution allows the boxes to
be easily disconnected and removed to be stocked sepa-
rately from the vessels or to ease the transportation of the
drones themselves.
To increase the possibility of future modifcations and ex-
pansions by the end-user, we adopted a modular approach,
(Top) The USVs navigating in the Genova rowing channel dur-
ing late-evening tests. (Bottom) The two USVs ready and wait-
ing for new mission orders. .