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

30 results of our testing we decided to go commercial with it,” he explains. The company’s hydrographers typically work in remote locations, with minimal technical and logistic support, and they wanted the USV to be reliable and simple to maintain. In pursuit of that, the company is now working on what it calls an embarked preventative maintenance system, to detect and log developing faults so that operators can address them before there is a failure. In-house autopilot Developed by Robopec, iXblue’s AI division, the autopilot and mission preparation software enables the DriX to operate autonomously offshore under supervision, with several of the craft operating independently but monitored by a single support ship. The autopilot maintains a minimum approach distance when operating in proximity to other assets or its support vessel to avoid collisions. It also maintains compliance with maritime anti-collision regulations, either automatically or through the action of a human supervisor. Manual override is possible at all times, says iXblue. The autopilot has a ‘take me home’ function, and the DriX is fitted with a homing beacon to aid emergency recovery. Engineers in the AI division created an autopilot architecture with three layers of software. At the bottom is the actuator layer, which sends direct movement commands to the engine and rudder actuators, for example. Above that is the autopilot layer, which keeps track of the vehicle’s state and formulates commands that enable it to carry out its programmed mission while complying with maritime regulations. The top layer is the mission control software that defines the mission through interaction with the off-board software in the operator interface. Eudeline stresses however that the DriX is compatible with any other mission control software, because the middleware between all the layers of software were written using the Robot Operating System (ROS). ROS is not an operating system in itself, rather it is a flexible framework for writing software across a wide variety of robotic platforms. A partnership with the University of New Hampshire in the US illustrates this broad compatibility. The university works with the US National Oceanographic and Atmospheric Administration, and in December 2018 it had a DriX that the university wanted to use for a series of sea trials using its own mission control system. “So we sent one of our software engineers over, and within 24 hours they were sailing with their software,” Eudeline recalls. All of the autopilot’s software layers need access to the DriX’s position, which they get from a GNSS/INS package in the gondola. As Eudeline explains, “You need an INS in the system to be able to geo-reference the collected data as accurately as possible, and the best place for it is with the sensor.” The INS is an iXblue Phins Compact 7, and is embedded in the gondola. Based on fibre optic gyro (FOG) technology, the Phins Compact 7 provides a claimed heading, roll and pitch accuracy of 0.01 º , a position accuracy of 0.05% of distance travelled in a package weighing 3.5 kg, measuring 200 mm in diameter and occupying a April/May 2019 | Unmanned Systems Technology The DriX Deployment System matches the USV’s motion in the water and has all the lifting points for launch and recovery (Courtesy of University of New Hampshire)