Hybrid cars to replace the Humvee
Sufficient booking has considerable weight, it is an obvious fact. Hence the demand for a more powerful and more voracious engine. Since the launch of a new car in the series a few years ago was not even discussed, some participants in the HMMWV replacement program decided to go along the slippery track of the experiment and try to create a military armored car with a hybrid power plant. The essence of this technology is as follows: on a classic car, the engine power is transmitted to the drive wheels through the transmission. On a hybrid car, in addition to the internal combustion engine, there is an electric one. Depending on the specific type of hybrid power plant, the ways in which they interact with each other and the drive wheels may vary. The most common at the moment is the scheme in which a gasoline or diesel engine drives a generator, and that, in turn, recharges the batteries and delivers electric current to the traction motor. The main plus of all "hybrids" lies in a noticeable reduction in fuel consumption. The fact is that a change in engine speeds affects fuel consumption, and a manual transmission due to friction losses, etc. also increases the amount of fuel required to some extent. When using a generator and an electric motor, the gasoline / diesel engine can operate at the same speed regardless of driving conditions. As a result, fuel consumption and emissions are reduced.
The most interesting and promising of the currently existing “hybrids” for the army is the L-ATV car (Light All-Terrain Vehicle), created at Oshkosh Corporation. This armored vehicle was originally created in accordance with the recently introduced concept of MRAP (Mine Resistant Ambush Protected - Protection from mines and ambushes). Therefore, L-ATV has a reservation that meets the second class of protection of NATO standards and can withstand hit 7,62-mm armor-piercing bullets or an explosion under the mine bomb with six kilograms of explosive. In the future, as they say in Oshkosh Corporation, it is possible to strengthen your own armor or even install additional panels - the power plant will allow you to do this without significant loss in driving performance. It is curious that the diesel and electric engines on the L-ATV interact in a so-called parallel circuit. A system called ProPulse implies that the electric motor does not drive the car independently at any stage of the trip. The electric motor helps the diesel engine to get the necessary power during acceleration, during slippage and in other situations characterized by increased fuel consumption. However, the designers have provided the possibility of movement only at the expense of the electrical system, but in this case, the power reserve is reduced by an order of magnitude. It is argued that thanks to this opportunity, the fighters will be able to move almost silently to the desired area, without being in danger of “catching” the enemy bullet. In addition to the original power unit L-ATV should pay attention to the suspension of this car. All four wheels have an independent suspension project TAK-4i. The mechanism of this system provides wheel travel in 20 inches, which should provide at least sufficient maneuverability for a relatively heavy car. During the tests, L-ATV was driven on a variety of surfaces, from deep snow to the sandy desert, and everywhere the speed and throughput were not worse, and in some cases better than the good old HMMWV.
Engineers from Oshkosh Corp., as if wanting to attract customers with additional “options”, have introduced a very interesting function into the composition of their armored car’s electrical system. It is understood that the charging of batteries should occur with the help of a running diesel engine - the power goes not only to the transmission, but also to the generator. However, if necessary, the crew of the car can literally plug it into a household outlet for recharging. Of course, it will take a lot of time to complete the "filling" of batteries, but this possibility will definitely not be superfluous. For example, during a battle, a diesel engine can be seriously damaged. In this case, the ability to recharge from the outlet, and the ability to drive only the electric motor is useful. In addition, L-ATV can be used as a mobile power station: electricity stored in batteries or generated by a generator, through a special set of cables, connectors, etc. can be fed to household electrical network. In this way, if necessary, power is provided to the headquarters, barracks or field hospital. Representatives of the development company argue that the cost of generating electricity by the L-ATV armored car does not exceed that of a large power plant.
TARDEC has its own views on vehicles of improved fuel efficiency and some of them apply to a hybrid power plant. During the FED project (Fuel Efficient Demonstrator - Fuel Efficiency Demonstrator) two prototype vehicles were created. With the names of the prototypes in TARDEC is not particularly wise. One received the letter “A”, the other began to be called “B”. Only soon, to heighten the convenience of the machine, they renamed it in accordance with the English phonetic alphabet. They became known as FED Alpha and FED Bravo, respectively. Outwardly, both cars are not different, and all the differences are hidden under the hood and bottom. "Alpha" is the most common armored SUV with a diesel engine. However, not all so simple. When similar to HMMWV curb weight with similar "loads" FED Alpha consumes only a third of the necessary for the Humvee fuel.
FED Bravo, in turn, has become a classic hybrid car. Unlike L-ATV, the TARDEC car uses only an electric motor for driving. The petrol or diesel engine on the FED Bravo is connected only to a generator. Interestingly, the "Bravo" can recharge their batteries, not only from the generator. For the same purpose on the roof and tailgate are solar panels. Obviously, the efficiency of such an energy source is low, but they can be useful as a supplement to the main generator. In the end, Alpha and Bravo are currently only concept cars. Like the L-ATV, the TARDEC “hybrid” is equipped with an electrical system capable of delivering and receiving electricity from the outside. Regarding the effectiveness of the use of FED Bravo as a power station data is not yet available.
Unfortunately, L-ATV and FED Bravo are military experimental machines. Therefore, accurate data on speed, fuel consumption or even on the level of protection is extremely small. For example, in appearance of the FED Bravo auto, you can make an assumption that its armor corresponds to the second or third class of protection. However, TARDEC does not confirm or deny these assumptions. But both companies involved in the creation of hybrid military vehicles, regularly brag about their success in promoting. The armored car L-ATV, by virtue of its age, has already been brought to the stage at which it is possible to manufacture an experimental batch for testing in the military. FED cars are still preparing to appear before the high commission of the Pentagon.
It is possible that in the very near future, the choice of US military officials will fall precisely on armored vehicles with a hybrid power plant. Yes, such a technique for various reasons is significantly more expensive than cars with “classic” engines and transmissions. But this disadvantage is confronted by several advantages at once: lower fuel costs, the ability to transport heavier loads and the ability of machines to perform not only transport tasks (mobile power station). The choice will not be easy, so decision-makers from the US defense department should carefully weigh everything and check it several times. Well, the military and engineers of other countries need, as they say, to wind on a mustache.
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