In the "Means" column of Online Defense, we examined the development and operation of the automatic transmission, highlighting its growing adoption in both the military and civilian sectors. The adoption of advanced vehicles is crucial for the armed forces, as technology also influences the military sector, opening up new specializations.
In Italy, known for its passion for engines, the acceptance of automatic transmission has been slower than in other countries, but today it shows a positive trend.
Change in perception of vehicles
Society sees the car less and less as an extension of the personality and more and more as a necessity with comfort. This change responds to traffic and limitations that hinder the use of the vehicle's performance.
Automation in military vehicles
Automation is inevitable in military vehicles for two reasons: the availability of components that can be used in both civil and military fields and the need to allow personnel to concentrate on operations, having their hands free.
Terminology and clarification
There is often confusion between terms such as "robotic" and "automated". In fact, they represent the same concept. DCT technology (Dual-Clutch Transmission) is the European evolution of the American hydraulic automatic transmission, offering lower consumption, reduced weight, greater speed and promptness. Brands such as Volkswagen (DSG), Audi (S tronic), Porsche (PDK), Fiat and Alfa Romeo (TCT) and twinamic for the Smart ForTwo they use this technology.
Operation of DCT systems
DCT gearboxes cannot be converted to manual, although they have sport sequential use. Terms like "robotic" often mistakenly refer to DCTs, which are actually automatic gearboxes in all respects, while robotized gearboxes are manual gearboxes with an electro-actuated clutch and a control unit that moves the synchronizers.
Differentiated maintenance
Maintenance varies: hydraulic gearboxes require oil and filter changes, while dual clutch gearboxes have similar needs to manual ones, depending on whether the clutches work dry or wet.
Technologies and driver skills
Today Ford and GM introduced the first 10-speed hydraulic automatic transmission. The more gears are available, the more the torque gaps are reduced. A traditional torque converter transmission is full of mechanical components necessary for its operation under hydraulic pressure. Why then should a double clutch, which uses gears keyed onto multiple shafts, be defined as "robotic"? Wouldn't it be more correct to talk about "dry gearbox" for manual or robotized gearboxes, and "automatic" for DCT gearboxes or gearboxes with converter?
Operational use
Let's examine a difficult uphill passage. Today, military vehicles use technologies such asHill Holder, reducing the need for traditional skills such as "heel and toe". Hydraulic automatic transmissions keep the vehicle stationary on steep climbs with constant hydraulic thrust, until you accelerate. However, in extreme conditions, the vehicle may slide slowly overcoming the hydraulic resistance of the pump. In DCTs, the creep function is intelligent and, based on inclinometer signals, raises the idle to overcome resistance and quickly connect the engine and gearbox. In the most severe cases, the control unit disconnects the clutch to avoid overheating.
Hydraulic gearboxes also have various clutches (lock-up on the converter and disc/belt on the epicycles), so putting them in neutral and then moving at traffic lights can wear out these elements. In DCTs, which have fewer clutches, this maneuver eliminates possible micro-rubbing.
Personal considerations
A test carried out on a DSG gearbox revealed its dependence on the control unit rather than on the driver. When towing, a dual clutch system can be deceived, especially due to the timing of the connection between the engine and the clutch. In military tactical vehicles such as the Light Multirole Vehicle Lynx a ZF converter system is used, as in the heavy 8x8 M1250.70T WM, where a 12-speed ZF AS automated gearbox Tronic it is crossed with a hydrodynamic clutch (a converter). Torque converters are preferred because they offer more reliable starting friction.
Examples of innovation
The first prototypes of hydraulic gearboxes in the automotive sector date back to the 30s in the USA. Subsequent experimentation led to numerous variants also in Europe, such as the CVT Van Doorne, the Fiat 850 Special Idroconvert of '60 and the semi-automatic Citroën DS of '55. The elimination of the movement of the gear lever on manual vehicles was achieved with the introduction of robotised gearboxes, initially designed for racing, and with systems such as the dual logic of Fiat, the MMT of Toyota, the MTA of the Fiat 500 Abarth or the robotic of Hyundai i10.
What the buyer sees is a similar, intuitive gear selector, but the underlying drive systems can vary greatly. The presence of the "P" position on the gear shift ring generally indicates that the gearbox is a double clutch or a traditional automatic, but not a robotized one. In heavy vehicles, including military ones, the "P" position is replaced by powerful vacuum brakes, so there is no point in desperately searching for the P button. A strategic choice to avoid damage to the harpoon system and prevent the vehicle from stopping. The concept of gear sequentiality is also quite commercial. Since the first traditional automatics, it was possible to set the gear positions individually, and today, with a number of gears up to eight, this functionality is even more useful.
In conclusion, both DCTs and converters have this opportunity to set exactly the desired gear, although, once used to it, it will be difficult to remove the selector from the D position. The evolution of gearbox systems has significantly improved efficiency and the reliability of both civil and military vehicles. Understanding the technical differences is essential to fully exploit the potential of modern transmission systems and not to be fooled.