The application of multi-criteria optimization to two-carrier two-speed planetary gear trains is outlined in this paper. In order to determine the mathematical model of multi-criteria optimization variables, the objective functions and conditions must be determined first. Two-carrier two-speed planetary gear trains with brakes on coupled shafts are analyzed in this paper. The mathematical model covers the determination of the set of the Pareto optimal solutions as well as the method for selecting an optimal solution from this set. A numerical example is provided to illustrate the procedure in which the optimal two-speed planetary gear train is selected and defined by design parameters.

The ever-increasing demands for vehicle emission control have resulted in an expansion of planetary gearbox applications in road vehicles, due to their possibility to change the transmission ratio under load in synchronism with engine operation. Modern boxes are designed to extract the maximum number of transmission ratios as possible from the least possible number of simple component planetary gear trains (PGTs). The application demands dictate whether the box will be built with the maximum number of transmission ratios, or built for ruggedness and reliability. Component interconnections are designed to avoid power circulation, hollow shafts, or complex planet carrier arrangements when possible. The subject of this paper are multi-speed complex planetary gearboxes having at least two interconnected simple component PGTs controlled by brakes and clutches. Several variants of complex PGTs are examined together with the placement of brakes and clutches on their external shafts, and their transmission ratio functions are derived. The kinematics of multi speed gear trains are analysed as combinations of two or more two-speed gear trains. Several gearbox layouts are analysed, and their transmission ratio functions provided. Finally, an overview of the procedure for the calculation of creation of multi-speed gear trains is provided.

The mechanical multiplier gearbox is one of the most important parts for wind power generation efficiency. Modern epicyclic gearboxes are compact, lightweight builds capable of high power ratings with coaxial input and output shafts. To achieve this, it is very important to select the proper internal gearbox layout and other relevant parameters in the early design stages as the wrong choices will result in a suboptimal solution. Parametric optimization was applied to select the optimal gearbox solution for a wind turbine application, while taking into account both two-carrier and three-carrier solutions. The large number of possible solutions has resulted in the development of the 2-SPEED software to conduct systematic analysis and comparison. The best five two-carrier solutions and the one best three-carrier solution have been selected from the solution pool, with the selection being based on the criteria of maximum efficiency, minimum weight, and minimal greater-ring diameter size. One optimal two-carrier solution was then selected from the five and compared to the three-carrier solution. Recommendations for the selection of either two-carrier and three-carrier gear train solutions according to the application demands have been deducted and provided. This will result in lighter, more efficient designs with smaller radial dimensions.

This paper outlines the optimum selection procedure for a two-speed planetary gear train with four external shafts based on two design and operational criteria: radial dimensions and efficiency. The paper outlines how to quickly determine the structure and important basic parameters of two-speed planetary gear trains that meet predefined transmission requirements. The procedure is followed by a numerical example in which the optimal two-speed planetary gear train is selected, defined by the teeth number of the central gears, modules and transmission ratios. The relevance of the presented results is reflected in the fact that these transmissions offer significant advantages in systems which require speed change under load.

In this study, an intelligent optimization system for laser micro-machining operations is developed, utilizing an Adaptive Neuro-Fuzzy Inference System (ANFIS). The heuristic optimization tool, ANFIS, synergistically combines back-propagation training with gradient descent in a unidirectional manner. A comprehensive training set, incorporating experimental data from the literature, highlights the sensitivity of groove depth and recast layer height to specific critical operating factors during the laser micro-machining process. By optimizing lamp current, pulse width, and frequency, the proposed system aims to achieve superior groove depth and recast layer height outcomes. This novel microscopic research holds the potential to captivate both academic scholars and industry professionals.

Planetary gear transmissions are essential components of industrial machinery due to their small size in relation to their rated power, high transmission ratios, and capability to transmit large torques within a compact design. They are widely applied in automotive, aerospace, and construction machinery industries owing to their reliable and efficient power transmission. The efficiency of planetary gearboxes directly influences energy consumption, operating costs, and environmental footprint. Power losses arise from gear and bearing friction as well as oil churning, and are determined by design parameters, manufacturing quality, lubrication properties, operating speed, and oil temperature. The accurate quantification of these losses is crucial for gearbox design, performance optimization, and durability, as well as for the development of energy-efficient control systems