Unmanned Systems Technology 025 | iXblue DriX I Maintenance I UGVs I IDEX 2019 I Planck Aero Shearwater I Sky Power hybrid system I Delph Dynamics RH4 I GCSs I StreetDrone Twizy I Oceanology Americas 2019

31 iXblue DriX | Dossier volume of 4.6 litres. Power consumption is quoted as 20 W. The GNSS portion of the navigation system is supplied by Trimble, but the autopilot is agnostic in this regard and can work with maritime-grade GNSS devices from a wide range of suppliers. Operation While the DriX normally operates in pre-programmed mode, it is overseen by two people: a supervisor who is responsible for safety at sea and the platform’s health, and a hydrographer who is responsible for the survey operation and data quality control. The supervisor maintains situational awareness of the surface picture, is on call to respond to any alarms and will take manual control if necessary to avoid a collision, for example. The principal sensors used to generate the surface traffic picture are infrared cameras from FLIR Systems and Lidar sensors from Velodyne, although again the system can work with sensors from any maritime supplier. “We try to remain agnostic so that we can install the sensors our customers want,” Eudeline says. Eudeline stresses that the Lidars are dedicated detection and collision avoidance sensors rather than scientific instruments. The vehicle also has an AIS transmitter to share its position with other AIS-equipped vessels in the vicinity. These days the DriX does not carry a radar as iXblue does not believe it is necessary. “Given the manoeuvring capabilities of the DriX, we do not need to see as far as a radar can,” Eudeline explains. He adds that the company would integrate one if a customer requested it. However, the DriX is fitted with devices on the ‘crow’s nest’ atop the mast to enhance the echoes it returns to other vessels’ radars, as its composite construction and low profile make for a small radar cross-section. The comms system includes Kongsberg’s MBR 144, a variant of its Maritime Broadband Radio for small manned boats and USVs, plus an IP-based Silvus Streamcaster radio, an Iridium satcom installation as an emergency back-up, and wi-fi. The MBR is a high-capacity mobile networking radio designed to carry large quantities of data over long ranges without the need for any supporting infrastructure. The 144 variant is a 2.5 kg enclosed unit with integrated omnidirectional antennas and a bracket for installation on vertical or horizontal rails. On the DriX it is mounted on a vertical rail above the rear of the mast. Providing a typical operational range of 20 km, depending on antenna placement and height, user data rates from 0.7 to 16.5 Mbit/s are available. It operates over frequencies of 4900-5900 MHz using channels 20 MHz wide. The Streamcaster radios use MIMO (multiple in, multiple out) techniques to exploit signals reflected from the surface of the water to improve comms for small vessels operating close to the water. Previously, such reflections were a source of interference, but now they can be used to increase the range, throughput and reliability of real-time transmission of video and data. They also form self-healing mesh networks of 20 nodes as standard that can be extended to more than 100, enabling multiple manned and unmanned vehicles to work in teams. Mission sensors As far as seabed mapping and survey sensors are concerned, iXblue has integrated multi-beam echo sounders (MBESs) and sidescan sonars from suppliers such as Kongsberg, Teledyne Reson, R2 Sonic and SonarTech, although Eudeline stresses that the DriX’s open architecture means any sensors that customers choose can be integrated. The MBES units include the Kongsberg EM 2040 and the EM 2040C. The latter is a compact, high-resolution system intended for shallow water surveys, and houses the receiver and the transmitter in a common head. The version of it that iXblue has integrated though has dual acoustic heads to cover a wider swathe on each pass, and features stabilisation in Unmanned Systems Technology | April/May 2019 iXblue DriX survey USV Configuration: wave-piercing monohull Materials: plastics reinforced with glass, carbon or aramid fibres Length: 7.7 m Height: 3.2 m Beam: 0.7 m Displacement: 1.4 tonnes Propulsion: naturally aspirated diesel engine Propellers: one Speed: 10-plus knots Endurance: up to seven days Payload power: two alternators and a 24 V lithium battery Control: autonomous, semi-autonomous and direct remote control Comms: networking IP radios, wi-fi, back-up satcom Some key suppliers Engine: Nanni Propeller and shaft: France Helices Battery: Solise Alternators: Balmar Autopilot: iXblue Communications: Iridium, Kongsberg, Silvus Navigation: iXblue/Trimble Thermal cameras: FLIR Systems Lidar: Velodyne Sonar: Kongsberg, Sonar: R2Sonic Sonar: Reson (Teledyne) Sonar: Sonartech Remote control: JMEI Datasheet