A number of western militaries are in the process of upgrading their ageing armoured vehicle fleets. Denmark, Poland, Canada and the United States are just some of the countries which have committed themselves to large modernisation programmes. The British Army is also beginning an extensive upgrade for its existing Warrior fleet.

Last month, Denmark's Defence Acquisition and Logistics Organisation concluded the testing phase on its armoured personnel carrier (APC) replacement programme. The competition to build 400 vehicles has seen BAE Systems, General Dynamics, FFG Flensburger and Nexter all submit bids. The tender includes both tracked and wheeled vehicles and V-shaped and standard-hull vehicles.

With so many options available, what are the most ground-breaking armoured vehicle technologies?

Vehicle protection

Hull: V-Shaped or Flat?

"The defining feature of these vehicles is the V-shaped hull, which deflects the force of a blast away from soldiers inside the vehicle."

Anti-tank mines and IEDs have become the weapon of choice in recent years, killing hundreds in Afghanistan and Iraq and maiming thousands more. As a response, western militaries have introduced newer equipment such as the Mine-Resistant Ambush Protected (MRAP) vehicle. The defining feature of these vehicles is the V-shaped hull, which deflects the force of a blast away from soldiers inside the vehicle.

But these vehicles are not without their flaws. The V-shaped hull means they have to be taller, which gives them a higher centre of gravity than normal, reducing mobility.

This has been a contributing factor to many accidents in theatre, which not only injures the crew but also leaves them dangerously exposed to enemy attack.

Because of these drawbacks and a move away from counter-insurgency operations (where IED threat levels are high), many armies across the world are staying with the tracked, standard-hull vehicle. The British Army is upgrading its flat-bottomed Warrior fighting vehicles to extend their life to 2040, while the US Army is likely to replace its Bradley vehicle with a similar flat-hulled system.

The V-shaped vs. flat hull debate will continue to rage for some time.

Composites

While disagreement lingers on vehicle hull design, there is at least consensus on introducing lighter materials in armour manufacturing. Similar to the aerospace sector, composite materials are being used to reduce weight, while still maintaining key ballistic and blast protection. Engineers claim they can now mould a vehicle shell that weighs just less than one tonne, rather than the two tonnes for steel, with similar protection properties.

Vehicles, like Supacat's SPV400, have a fully composite armour 'pod' which can also be supplemented with ceramic plates if necessary.

Reducing weight through using composites means a vehicle can carry more fuel, ammunition and troops if required. Using composites will also reduce a vehicle's overall through-life costs, while increasing its service life, mainly because composites will not rust or suffer from fatigue like metal parts.

RPG armour

Vehicles deployed to Afghanistan and Iraq are fitted with slat armour - also known as bar armour - which is designed to sits inches away from the main armour and disrupt the shaped charge of a rocket-propelled grenade when it explodes. But this vital lifesaver also has its drawbacks, which are being addressed in newer armour.

"Reducing weight through using composites means a vehicle can carry more fuel, ammunition and troops."

In a similar vein to composite technology, slat armour is being revolutionised using robust textile-based materials instead of metal. Lightweight protection like Amsafe Bridport's Tarian armour uses complex interlaced fabrics and materials inside a protective coating, giving it the appearance of a heavy-duty metal wire, but is actually very light fabric.

"It is incredibly lightweight," says Tarian product line manager Mike Taylor. "It only weighs ten percent of the old bar armour that's fitted to most vehicles traditionally. For the first time we can fit an RPG protection system to a lightweight vehicle such as the Navistar Huskey vehicle."

Tarian can be repaired by non-specialist soldiers and also disassembled in around 20 minutes. The revolutionary armour can fold flat against the vehicle it is fitted on and does not have to be removed for transportation, which saves time and money.

Systems and sensors

Communications

Future vehicles will give soldiers unrivalled tactical capabilities by being networked to other military assets while also being able to drive in all weather conditions, day and night. This is thanks to systems which give the warfighter real-time situational awareness on the battlefield and unrivalled command and control capabilities.

"Future vehicles will give soldiers unrivalled tactical capabilities by being networked to other military assets."

In the last decade, the US Army has fielded the successful Force XXI Battle Command, Brigade-and-Below (FBCB2) communications platform across its deployed vehicle fleet. The system, which first saw use in Iraq, allows vehicle commanders to view real-time data on the location of friendly and enemy forces. The information is relayed on ruggedised touch-screen displays, which can give accurate locations on detailed maps and email-like communication between units.

The platform is now in the process of further upgrades costing the US Army US$455m, this includes new ruggedised wireless tablets with vehicle docking stations and upgrading satellite network speeds. Information availability will also be increased with soldiers able to plot the location of IEDs for units on the network and also send text messages for medical evacuations if radio communications are not available.

Optics

Additionally, the situational awareness afforded by systems like FBCB2 - and the British Army's Bowman system - can be supplemented with advanced optics, which give vehicle operators unparalleled vision in low-visibility conditions. BAE Systems' Driver's Vision Enhancer (DVE) equipment, a series of infra-red cameras and driver displays, means soldiers can see clearly at night and in fog and dust.

This, coupled with FBCB2, gives commanders a superhuman view of the battlefield and a significant tactical advantage.

Because DVE systems rely on long-wave infra-red - a significant step-up from night-vision equipment - vehicle displays can also pick up heat signatures from IEDs and recently-fired weapons. Technology like this has proved vital in reducing casualties and will continue to do so in future conflicts, as the capability evolves.

Vehicle components

Wheels and tyre technology

European vehicle procurement has shifted to medium-weight wheeled vehicles such as France's Véhicule Blindé de Combat d'Infanterie (VBCI). But these vehicles remain vulnerable to small-arms fire and shrapnel, especially their soft rubber tyres, which can be immobilised with relative ease. Manufacturers are finding innovative ways to reduce this with advanced components such as runflat technology.

Tyres are the primary target in immobilising a wheeled vehicle. It is therefore vital that a vehicle can escape at high speed, or complete its mission with one or all tyres flat. Hutchinson, a subsidiary of petroleum-giant Total, offers militaries worldwide runflat technology. Their Beadlock system ensures the tyre beads are clamped at all pressure conditions, preventing the tyre slipping when punctured.

Vehicle operators can also optimise off-road performance by varying the pressure inside the cabin, without any need to go outside.

This means tyres can be deflated when off-road but also inflated when using normal tarmac roads. Most wheeled armoured vehicles developed today have this technology fitted as standard.

Hybrid engines

Armoured vehicles and tanks have traditionally been gas guzzlers - the M1A1 Abrams tank needs two gallons of fuel to go one mile - but developers are looking seriously at green technologies for future vehicles. To have vehicles at your disposal which rely less on fuel, and the costly logistical process this entails, is a valuable asset for any military planner.

"Manufacturers are finding innovative ways to reduce this with advanced components such as runflat technology."

Last month, the US Army Tank Automotive Research, Development and Engineering Center (TARDEC), began the advanced testing of a new hybrid Ultra Light Vehicle (ULV). The ULV is driven by two electric motors and a lightweight diesel engine, the latter provides power to the motors and high-torque at low speeds. Importantly, the electric motors eliminate the need for a driveshaft and so the underbody will perform better in an IED or mine blast.

A smooth underbody, coupled with protection comparable with currently-fielded MRAPs, means the ULV could offer enhanced survivability for soldiers. The ULV is purely a proof-of-concept project, which is funded by the Office of the Secretary of Defense, but it already demonstrates significant advances in vehicle design. In only 16 months, the project has quickly moved from design to prototype.

Weapons

Remote weapon systems

Since the campaigns in Afghanistan and Iraq, there has been a significant shift from manned weapons on vehicles towards newer remote-controlled systems. BAE Systems South Africa has developed the Tactical Remote Turret (TRT), a modular system which can support a number of weapons.

TRTs offers several advantages over legacy systems, including multiple weapon systems on one turret, rapid-fire cannons (20mm or 30mm), co-axial machine gun and anti-tank guided missiles. The use of electro-optical sights means an enemy can fired upon from up to 3,000m away, and with infra-red, almost 8,000m away at night.

Renault Trucks Defense (RTD) has fitted the TRT system to the newest iteration of their popular VAB APC, the Mk III. RTD say there is more protection for the soldiers because they do not have to go outside the vehicle and it is lighter. There are no mechanisms for the turret inside the vehicle, so internal volume is maintained.

Lasers - the directed energy weapon option

Looking beyond conventional bombs and bullets, manufacturers are also experimenting with vehicle-mounted directed energy weapons (DEW) - or lasers. Boeing converted one of its AN/TWQ-1 Avenger air defense systems - a modified Humvee capable of firing Stinger missiles - with a solid-state laser weapon. The 'Laser Avenger' system was the first-ever vehicle to shoot down a UAV with a laser. Boeing says the system can be operational within a year and can also destroy IEDs.

Lasers offer a number of advantages over conventional weapons. They do not require ammunition resupplies - reducing logistics costs - and also offer rapid engagement of multiple targets. The US Army has yet to make any firm decision on Boeing's Laser Avenger, but DEW technology remains a rapidly advancing technology across all domains.

Concepts

Modular systems

"TRTs offers several advantages over legacy systems, including multiple weapon systems on one turret."

Modularity, in military procurement terms, can often be interpreted as 'more bang for your buck'. Instead of buying a piece of equipment to carry out just one job, it is expected to take on Swiss-army knife qualities and carry out multiple roles. In the current age of austerity where every dollar counts, the modularity concept has again become the buzz-word for defence equipment procurement.

"Modularity is really the key word for the future," said Michel Lautier, a former French colonel and military advisor to Nexter, who have just unveiled their new Titus modular vehicle.

This concept mirrors the changing concepts in tactical and strategic thinking, especially with the withdrawal from Afghanistan. Militaries across the world are concentrating on aligning their capabilities to a broad spectrum of conflict scenarios. After all, a vehicle designed for counterinsurgency may be useless in the next conflict.

Modular vehicles can adapt to different roles, often using 'operational kits' which can be fitted or removed with relative ease and low cost. In the current period of austerity, this is an important capability for cash-strapped armies.

The return of the flying car

A piece on future systems can not fail to mention the Defense Advanced Research Projects Agency (DARPA). They are halfway through a five-year programme called DARPA TX or Transformer - a vehicle which will have vertical take-off and landing capabilities and can travel up to 250nm on a single tank of petrol.

Lockheed Martin's Skunk Works - the team behind the SR-71 Blackbird and F-117 Nighthawk - is proposing a vehicle that will feature a pair of tilting ducted fans, which allow it to travel up to 200 knots and 10,000ft in the air. Lockheed could receive a contract to produce Transformer TX for its first flight in 2015.

Although it is not likely to see operational combat for some years, DARPA's project shows how far the century-old armoured military vehicle has come. This, along with technological advances in armour protection, systems and sensors, components and weapons means armoured vehicles will remain an essential part of the modern military's inventory for the foreseeable future.

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