Mine busters

During the first Gulf War, Iraq laced the Kuwait shoreline with tens of thousands of underwater mines in an attempt to stop US marines from landing. After the war, minesweepers removed more than 13,000 mines from the Persian Gulf but military officials believe there are many more to be found, presenting an ongoing danger to troops now stationed in the area.

However, dealing with the arsenal of underwater mines around the world is a terrifyingly dangerous business.

Despite the range of robotic options available to the world’s navies, in many cases mine clearance relies on specially-trained scuba divers, who swim down to visually identify the target or place explosive charges to dispose of it. Unsurprisingly, these missions are fraught with danger.

The latest tool to keep service personnel at a safe distance is the Talisman, an autonomous unmanned underwater vehicle (UUV) developed by BAE Systems, which can detect and destroy underwater mines. Its first production-ready model is being tested and it is hoped this car-sized robotic vehicle can help eliminate the need to use scuba divers in locating and destroying mines.

BAE System’s Andy Tonge is the Talisman’s project manager at the firm’s Underwater Systems Group, based at Waterlooville near Portsmouth. In his opinion mine warfare is a factor of more than just current conflicts; there are also many mines that have lain undiscovered since World Wars I and II.

‘Mine warfare is a war activity where the technology is very cheap and easy to use, so it will always be an issue,’ he said. ‘What we need is a technology that enables us to remotely operate from over the horizon with a degree of autonomy.’

Talisman is the combination of three phases of mine clearance technologies. One sonar-equipped vehicle is used to go out and locate mine-like objects, followed by a second vehicle equipped with cameras that can classify them. The third phase, which in some cases consists of little more than a trained clearance diver, is then engaged to dispose of the mine. Talisman is designed to combine these phases into one, sleek, manoeuvrable vehicle.

While Talisman is designed to autonomously detect and classify mine-like objects, human input is still required for the actual disposal, albeit from a distance. Upon the discovery of a mine, Talisman rises to the surface and transmits data via UHF radio to the command ship, which could be up to a few kilometres away. A human operator then controls the disposal technology — the BAE-designed remotely-operated vehicle called Archerfish.

Each Talisman vehicle is fitted with four ‘Archerfish’ single-shot mine neutralisers, which are connected to the Talisman via fibre optic cable. The Archerfish goes in to video the suspected mine and this footage is transmitted back to the command ship. The operator on board the ship can then use the Archerfish to detonate a charge to dispose of the mine.

For Tonge it is crucial that a human operator takes control of this vital, final stage. ‘Even though the technology is very close to support full autonomous disposal of mines, you have to have a man in the loop to make sure first that it is a mine you are destroying and also to make sure it is done satisfactorily,’ he said.

Although Talisman is built as a stealth submarine, it must rise to the surface before it can transmit video because underwater acoustic communications do not have the bandwidth to support video streaming, said Tonge.

Talisman: the first production-ready model is being tested. It is hoped this car-sized robotic vehicle will eliminate the need for scuba divers in identifying and clearing mines

An interesting factor behind the Talisman design process is that it extended beyond the usual confines of the defence industry. BAE worked with motor-racing expert Lola Racing to develop the vehicle’s unique body. As a result, the Talisman’s 4.5m hull and its internal compartments are all made from carbon fibre composites that lower its weight and enhance its manoeuvrability in the water.

‘It has a similar look and feel to an E-Type Jaguar,’ said Tonge. ‘There are certainly parallels with the racing industry in terms of its low drag shapes and others such as engine technology.’
BAE decided it wanted Talisman’s manoeuvrability to be similar to that of the Harrier jump jet so the submarine could hover in one place under water or even land on the sea bed. To do this the propulsion system — a series of fan-like thrusters — is distributed throughout the vehicle, making it extremely manoeuvrable with each thruster moving independently on its axis to give Talisman 360º freedom of movement.

The engine is a hybrid system that consists of a highly efficient battery-powered electric drive for when the submarine is beneath the surface, coupled with a small, high-power Cosworth diesel engine that is also used to recharge the battery.

But it was not technology transfer alone that made BAE decide to work with Lola Racing and its subsidiaries. Tonge said BAE also wanted to use the ‘rapid response’ culture found in the motor-racing industry. ‘Their deadlines are so short and aggressive it’s almost unbelievable. If we can do the same in the defence industry that’s really giving us a technology and business boost.’

While defence projects — particularly top-secret ones such as Talisman — are typically drawn-out affairs that last for several years, Talisman has been rushed from blueprint to being almost ready for full production within two years.

BAE’s work with Lola Racing is the main reason for this change in working culture, according to Tonge. It contracted one of Lola’s subsidiaries on 21 December last year to produce a prototype composite shell for the Talisman body. To BAE’s amazement the completed composite shell was delivered by the end of March. ‘It’s a culture change but it also brings in new technologies that people in the defence industry are not always aware of, such as rapid prototyping and carbon fibre construction techniques and the use of moulded structures,’ said Tonge.

While Tonge was unable to officially comment on reports that Talisman is fitted with stealth capabilities, it is reasonable to assume it is. He admitted that much of the work on Talisman was inspired by other work under way in other areas of BAE, particularly its work on UAV technology. BAE’s Taranis UAV project (The Engineer, 29 January) is to use a number of innovative stealth materials to help give it a low-radar profile.

‘We are putting together some of the key technologies from across BAE Systems land sea and air so we can get a totally integrated strategy,’ said Tonge. ‘It means we can design something once and then reuse it, particularly in things like data fusion, mission planning and a lot of the software aspects.’

Talisman has been engaged in secret trials around the UK’s coast over the past few weeks but Tonge would not be drawn on when it will enter service or who its first customers will be. It has been reported that Talisman could be deployed from aboard the Royal Navy’s new Astute submarine, which Tonge conceded was not outside the realms of possibility.

However, he did say he believes Talisman is a big step towards the next generation of mine clearance technologies.

‘Talisman can be put in an aircraft and taken somewhere so it is the first vehicle at the scene, not the last,’ he said. ‘It means we can change the way we go about the mine-hunting task, allowing it to be operated from a command and control aircraft or even from the shore. It is going to change the way we work.’