Maritime drones: Eviden unveils SMX, an electromagnetic navigation sensor

The French company Eviden has unveiled the SMX, an electromagnetic speed sensor for maritime drones. It was developed specifically for unmanned vehicles operating on and below the surface. Compact, robust and almost silent, it is designed to make their autonomous navigation more precise and reliable.

The sensor continuously measures how fast a vehicle is moving relative to the surrounding water. Eviden developed the SMX under its BEN Marine brand. These data are essential for calculating the distance travelled, determining the remaining distance to the destination and feeding autonomous navigation systems with precise information.

The system is aimed primarily at the unmanned surface vehicle (USV) and unmanned underwater vehicle (UUV) classes, including mine countermeasure drones. Eviden also lists torpedoes, crewed underwater vehicles for divers and other maritime platforms as possible applications.

Maritime drones without an acoustic signature

The SMX derives its main advantage from the electromagnetic measuring principle. The system emits no acoustic signals, whereas acoustic speed sensors do. For underwater military operations that require the lowest possible acoustic signature, this is an important factor.

Weighing less than two kilograms, the sensor withstands pressures of up to 30 bar, equivalent to a water depth of around 300 metres. All of its electronics are housed in the sensor itself. The system also meets military MIL-STD requirements.

The speed data are passed to the navigation system via a standardised NMEA interface. Because calibration and diagnostics can be carried out remotely, maintenance effort and downtime are expected to fall.

The SMX is developed and manufactured entirely in France and is based on the proven predecessor system SM 2000. Sensor production, final assembly and qualification take place at Eviden's site in Aix-en-Provence.

Eviden sees applications not only in the military sector but also in civil shipping and oceanographic research. The company did not comment on initial customers, quantities or prices.