The temperature achieved at the contact surface of the disc and the pad of a friction brake during its operation has a significant impact on brake performance. Temperature measurement techniques, which are usually available under laboratory test conditions, enable obtaining relatively accurate values of the temperature at the friction surface. However, measuring the sliding surface temperature during the entire lifetime of the brake pad is very difficult due to the demanding operating conditions of the brakes, i.e. the appearance of wear, the presence of water, corrosion, and other immersive impacts. Purely mathematical models for the prediction of friction or contact surface temperature are often complex, and they are affected by a number of limitations. In this paper, an appropriate mathematical model was developed in order to enable estimation of the sliding surface temperature values between the brake disk and brake pads throughout the entire duration of brake application. This is achieved by using the results of the temperature measurement within the brake pad and its processing, by means of an originally developed mathematical model.

Vojna akademija-Odsek logistike, Beograd Rezime: Odre|ivanje osnovnih kinemati~kih i dinami~kih karakteristika slo`enih planetarnih prenosnika je slo`en proces za koji je razvijeno vi{e analiti~kih, grafi~kih i grafoanaliti~kih metoda. U radu je prikazan na~in odre|ivanja prenosnog odnosa, optere}enja elemenata i tokova snage za planetarni red sa spolja{njim i unutra{njim ozubljenjem preko polu`ne analogije i primene strukturnog (Wolfovog) simbola. Polu`na analogija definisana je i za planetarni red sa spolja{njim ozubljenjem, za koji je, tako|e, definisan strukturni simbol. Definisani strukturni simboli iskori{}eni su za definisanje strukture prenosnika tipa Ravigneaux. Primena strukturne {eme za analizu karakteristika slo`enih planetarnih prenosnika ilustrovana je kroz analizu odre|enih funkcionalnih stanja planetarnih menja~kih prenosnika. Posebno je definisana mogu}nost analize blokiranih stanja planetarnih me-nja~kih prenosnika. Klju~ne re~i: planetarni prenosnici, prenosnik Ravigneaux, polu`na analogija, strukturna {ema, analiza stanja.

Unlike independent steering systems on wheeled vehicles, the steering mechanism on high-speed tracked vehicles are integrated in the power train system, therefore turning process consumes more engine power than straight driving scenario. To ensure the most efficient turning performance, power trains of high speed tracked vehicles are equipped with complex turning mechanism components which are, most frequently, mechanical or hydrostatic. In most cases mechanical components enable turning process by slipping of the clutches and other frictional components, which is inconvenient from the aspect of power balance, as well as from the performance aspect. On the other hand, hydrostatic components have low efficiency in certain working ranges. Modernization of the conventional mechanical systems by applying electric drive components can contribute to solving the mentioned downsides, given the fact that modern electric drive systems can have very sensitive torque and speed regulation which significantly improves electric drive performance. Applying these electric drives in auxiliary power flow ensures additional flexibility and the possibility for the power train to work in different working regimes, such as energy regeneration, which improves the power train efficiency. This paper includes a variety of possible hybrid power trains for high-speed tracked combat vehicles and a fully developed simulation model of a hybrid drive for power trains with two power flows (main and auxiliary). The simulation model provides the possibility to observe the quantified influence of the certain parameter change in the turning process and allows us to identify the important parameters for power train control during the turning process.