In recent years, robotic systems have been used increasingly by the military. While they have proven their worth in the air, on the ground and underwater, unmanned surface vessels (USVs) have been the overlooked system. Now is the time for them to gain the credit they deserve.

The success of the majority of automated systems can be attributed to the urgent production requirements of countries involved in conflict. For instance, the use of unmanned aerial vehicles (UAVs) in current and recent conflicts has thrust the systems into the limelight.

Drones ranging in size from that of a small bird to a full-size fighter jet regularly take part in reconnaissance, surveillance and detection missions, and increasingly adopt attack roles. UAVs the size of a football pitch will soon be able to stay aloft for months at a time, providing near-orbital persistent monitoring and communications. The international military and civilian UAV market is expected to be worth $80bn by 2020.

Increasingly sophisticated land robots have also taken to the battlefield. Having found their niche in bomb detection and disposal, their use in providing logistical support for dismounted troops and even retrieving wounded soldiers from the front line is being explored.

Autonomous underwater vessels (AUVs) have a long history in the oil exploration industry, and in exploring shipwrecks and wildlife. International navies are now using the vessels for mine clearance, and they could have future roles in submarine warfare and underwater communication.

However, despite successful tests dating from WWII and the efforts of several companies to change the situation, the surface equivalent of AUVs, unmanned surface vessels (USVs), have yet to find their niche.

As with UAVs, Israel was one of the early adopters of USV technology. The Israeli Navy was one of the first in the world to operate the vessels, using the Protector USV built by Rafael Advanced Defense Systems. The Singaporean Navy has also deployed USVs, while demonstrations have been given to the US Navy and Coastguard as part of the Littoral Combat Ship Programme and the Integrated Deepwater System Programme.

A Swedish shipyard, Kockums, makes the Piraya USV, a boat with stealth capability used by the Swedish coastguard to patrol coastal waters. Several Pirayas can be operated at once by a single human operator, and a fleet of three has already been tested. The company also makes SAM 3, a minesweeping USV, while SIEL, an Italian company, manufactures UAPS 20, an unmanned autopilot system designed to transform standard motorboats, especially rigid hull inflatable boats, into USVs.

To date, purpose-built military systems have been few and far between. However, the US Defense Advanced Research Projects Agency (DARPA) is now working on its own USV. Indeed, the agency launched a project in 2010 to develop the ASW continuous trail unmanned vessel (ACTUV), a surface vessel to track and trail submarines.

USVs were originally designed to protect coastlines from the smuggling of contraband and people, and to protect borders. However, with at-sea terrorism and kidnapping, and piracy on the rise, USVs could soon be as familiar as the squadrons of UAVs that currently patrol the skies.