A bout the size of a WW II-era Jeep and three times the torque of a Dodge Viper, the Quantum Alternative Mobility Vehicle (AMV) has the appearance of a large, futuristic all-terrain vehicle. Known also as the Aggressor, the Quantum AMV could portend the future for lightweight, battlefield-ready mobility vehicles for silent operation missions with the ability to export power to run electronics on the battlefield and only emit water from the tailpipe.
Lightweight vehicles like militarized electric bikes, ATVs, motorcycles and small utility vehicles are already on duty with military forces in Iraq and Afghanistan. The AMV was developed by Quantum Fuel Systems Technologies Worldwide Inc. for the U.S. Army's Tank-Automotive Research, Development and Engineering Center's National Automotive Center (TARDEC--NAC).
The recently shown demonstration model AMV is a high performance, fuel cell-powered, off-road vehicle designed to provide troops with high mobility when performing stealth missions. Rather than being designed for a narrow set of applications, this demonstrator is aimed at showing the flexibility to perform a variety of tasks, including commercial applications.
For example, the Aggressor features a 10 kW proprietary PEM-style fuel cell stack. The demonstrator AMV was configured so that fuel cells front a wide variety manufacturers could be integrated seamlessly into the vehicle. The fuel cell is combined with an Energy Storage Module (ESM) that allows either a hybrid series or parallel mode of operation.
Quantum's proprietary ESM uses both capacitance and battery technology to provide both high peak short duration and long duration energy storage. Power is delivered to a proprietary, high-torque electric motor driving the rear wheels. The flexible design could also be a 4x4 using, for example, hub motors in each wheel.
The compressed hydrogen fuel is stored in Quantum's TriShield Type IV impact-resistant, 100% composite and carbon fiber storage tanks coupled with the company's in-tank regulators and sensors and shut-off valve to create the Fuel Storage Module (FSM). The FSM holds approximately 4.4 lb. of hydrogen at 5000 psig. The TriShield is designed so the external carbon fiber wrappings form a tough and very durable shell that should provide protection against bullets and shrapnel.
One of the standard tests performed on this type of fuel tanks is the bullet test to determine how the tank will perform should it be punctured. The goal is a tank that does not explode or shred, but releases its contents slowly. The TriShield tank passed all testing protocols, including the ability to withstand a 30 cal. round.
The TriShield design performed so effectively that the round fired did not damage the tank at all, and a 50 cal. round was required to penetrate the tank.
According to Quantum, properly stored and handled hydrogen is no more dangerous than munitions or other high-energy ordnance currently found on the battlefield.
When power is drawn from the ESM and fuel cell, a maximum peak power of 80.5 hp and a peak torque of 1681 lb.ft. are available. The latter allows the Aggressor to accelerate about twice as fast as comparable all-terrain vehicles with unmodified gasoline or diesel engines--from zero to 40 mph in under four seconds, Quantum said. Acceleration is limited by traction rather than power available, as the electronic control system imposes torque and speed limits on the drivetrain to enhance traction and safety. Ungoverned, Quantum said the Aggressor can reach speeds in excess of 80 mph.
The Aggressor has an 85 in. wheelbase and the overall length of the demonstration vehicle is 140 in. Other variants and body styles could be as long as 200 in. The AMV is 66 in. wide and 60 in. high. The 10.1 in. ground clearance and 6 in. of suspension travel assure great agility for serious off-road operations, the company said.
Of course, a big issue is the logistics of transporting hydrogen to the battlefield and then handling it there safely. According to Quantum, there are a number of ways hydrogen could be delivered to the battlefield. The first method is to generate the hydrogen in-situ using renewable sources such as solar cells to electrolyzed water to produce hydrogen, compress it, store it and make it available for refueling. The other method is to use pre-fill tanks and package them for transport to theater of operations.
Another issue is how hydrogen would fit into the military's "single battlefield fuel" strategy. Hydrogen would most likely be considered an "optional" fuel, used only for special missions.
Using a fuel cell-powered vehicle on the battlefield offers many advantages that greatly outweigh the added logistics complications associated with using hydrogen. The foremost consideration is that it could be operate in a stealth mode being able to travel virtually silently with a g-ready reduced thermal signature making it much more difficult for IR (infrared) sensors to detect. Additionally, the AMV could be driven to the intended destination and then be used as a silent power generator to produce high quality electricity. The military needs a source of field-deployed exportable electrical power that is generated silently for special missions such as surveillance, target acquisition, telecommunications, etc. Being able to incorporate this with a mobility unit capable of getting the warfighters where they need to go, when they need to go is critical.
Finally, the vehicle does not produce any emissions besides water in any of its different operating modes.
The Aggressor is currently undergoing extensive testing. From these tests, additional information will be compiled and changes, if any, would be incorporated. The military is also interested in other variants of the Aggressor, which might include a diesel/electric hybrid version.
