In computational engineering, enhancing the simulation speed and efficiency is a perpetual goal. To fully take advantage of neural network (NN) techniques and hardware, we present the SLiding-window Initially-truncated Dynamic-response Estimator (SLIDE), a deep-learning based method designed to estimate output sequences of mechanical systems and multibody systems, in particular, which are subject to forced excitation. A key advantage of SLIDE is its ability to estimate the dynamic response of damped systems without requiring the full system state to be known, making it particularly effective for flexible multibody systems. The method truncates the output window based on the decay of initial effects due to damping, which is approximated by the complex eigenvalues of the system’s linearized equations and is only limited by the lack of transfer of internal states between evaluations. In addition, a second NN is trained to assess the accuracy of the surrogate model by estimating the error during inference, further enhancing the method’s applicability. The method is applied to a diverse selection of systems, including the Duffing oscillator, a flexible slider-crank system, and an industrial 6R manipulator, mounted on a flexible socket. Our results demonstrate significant speedups from the simulation up to several millions, exceeding real-time performance substantially.

In the present work, the inverse trigonometric shear deformation theory (ITSDT) is applied to analytically perform the free vibration and buckling analysis of functionally graded (FG) sandwich plate. The governing equations are derived using the principle of virtual work, incorporating linear structural kinematics and the generalized Hooke’s law. These equations are solved in closed form for simply supported boundary conditions to obtain the buckling and vibration response. For the analysis, two types of FG sandwich plates are considered i.e., Type – A and Type – B. For the Type – A plate, the core and face sheets of the FG sandwich plate are made up of Ceramic and FG material, respectively. Whereas in case of Type- B plate, the core is composed of FG material, while the top and bottom face sheets are made up of ceramic and metal, respectively. The power law is employed to vary the material properties in the FG material. The evaluated results for the FG sandwich Type – A plate are compared with the already reported results in the literature wherever possible and are found in good agreement. The influence of the various parameters such as span to thickness (a/h), aspect ratio (a/b), power law index (p) and core thickness (schemes) are investigated on the dimensionless fundamental frequency and dimensionless critical buckling load of the FG sandwich plate, on those basis, noteworthy conclusions are drawn.

Traditional coconut dehusking methods, reliant on manual labor, are plagued by inefficiency and inconsistency. Existing attempts at mechanized approach have not provided the solution scientifically. The present solutions have not been validated scientifically in terms of speed, yield, safety etc. In addition, the existing designs are not optimized or varying coconut sizes, shapes and maturity. This article presents a power-operated dehusking machine at nominal speed and high yield to achieve consistent husk removal. The machine’s core design prioritizes safe and efficient dehusking. The focus on functionality leverages a power-driven mechanism to minimize human effort and maximize processing throughput. The structural stability and durability of critical dehusking components are meticulously calculated to ensure reliable operation, using static stresses, stress analysis, high cycle fatigue analysis, and finite element analysis. Comprehensive proof-of-concept tests using various performance metrics such as the coconut size, shape, maturity, dehusking time, etc. are measured in each case, which validated the machine’s functionality and performance across a range of coconut sizes, confirming its ability to consistently remove husks effectively. A subsequent performance evaluation assessed the machine’s throughput rate, dehusking rate, number of crushed coconuts, and the reasons for failure in dehusking. The developed machine achieved a dehusking rate of 200 coconuts per hour, with a remarkably low rate of crushed coconuts at only 10 coconuts per hour.

This article investigates the weaknesses in the hoisting device of the diesel engine of Vale mining company’s locomotives, located in Vitória, ES. Composed of two parallel plates of ASTM-A36 steel, the device showed permanent deformations that highlighted the need to improve its mechanical resistance, especially in the support regions. In view of this, the study proposes five alternatives to increase the resistance and useful life of the device, highlighting the replacement of the material, the use of cylindrical and elliptical bushings of AISI 1045 steel, the increase of the geometry in the lower region of the component, and the removal of regions with low mechanical demand. The proposals are evaluated numerically through the Finite Element Method (FEM), using polynomial nodal shape functions of the 1st degree. The techniques presented better distribute the stresses in the body and, when using the bushings, allow the part with the highest mechanical demand to be replaced in case of degradation. The main contribution of this work lies in the emphasis given to the geometry of the points of application of force, highlighting the elliptical bushings of AISI 1045 steel as the most promising option, presenting the lowest maximum stresses.

Teleoperation robot systems allow people to stay away from dangerous environments and realize remote work, which not only ensures personal safety but also greatly improves work efficiency. In order to solve the problem of insufficient damping force and slow response speed of the force feedback device, a new type of force feedback device is proposed by taking advantage of the controllable and fast rheological effect of magnetorheological (MR) fluid. The structure of the MR force feedback device is designed, its kinematics is analyzed by numerical calculation, the displacement and velocity of each component are analyzed by finite element simulation, and the position accuracy and mechanical properties of the MR force feedback device were measured through experiments. The results show that the working range of the force feedback device is 156 mm × 156mm × 217mm, with the position error less than 2.4 mm and the output force range from 0.6 N to 21.5 N.

Bogie and pantograph areas are the important sources of the aerodynamic drag for high-speed trains. In this study, a smooth and fully encapsulated structure in bogie areas and a teardrop deflector in pantograph areas were designed to improve the train aerodynamic performance. Herein, two different three-car grouping high-speed train models were employed, i.e., Models I and II. The numerical simulations were carried out using an improved delayed detached eddy simulation (IDDES) method. The results show that after installing the smooth and fully encapsulated structure in bogie areas, the aerodynamic drag coefficients of bogie regions of the head and tail cars are reduced by 59.4% and 57.0%, respectively. In addition, the wake flow of the high-speed train is improved as well. The similar reduction is observed in the pantograph area. After installing the teardrop type deflector, the airflow over the pantograph area becomes smoother, which contributes to 45.6% aerodynamic drag reduction in the pantograph area. Therefore, combining with the smooth and fully encapsulated structure and teardrop type deflector, the Model II achieves an aerodynamic drag reduction of 17.3%.

A novel coupled spring pendulum vibrating screen is proposed with the goal of developing energy saving and efficient screening by making use of parametric resonance of the dynamic system. A 3-DOF theoretical model of the vibrating screen is developed. Extensive numerical simulation has been performed and the results revealed that a system where attributes are sized for parametric resonance requires far smaller excitation forces to achieve higher accelerations and displacements compared to traditional vibrating screens. The new dynamical system also yields complex motion which is novel compared to the motion of traditional vibration screens. Discrete element simulations of the proposed vibrating screen are performed and the results reveal that the proposed screen, compared to traditional vibrating screens, requires far less energy and achieves higher efficiencies with larger deck inclinations. Experimental validation is performed by free vibration tests. It is found that the numerical simulations and experimental tests present a good consistency or correlation.

This study investigates dynamic behavior of railway bridges subjected to lateral impact load induced by over-height vehicle while a train passes over the bridge. The lateral displacement at the bottom of the bridge girder subjected to impact load is first compared with the specified value considering the bridge elastic and plastic behavior using finite element model (FEM). Then, in the railway bridge sector, different sensitivity analyses are performed on the parameters of lateral displacement, vertical and lateral bridge deck acceleration, sleeper lateral displacement and vertical and lateral rail acceleration on the same and opposite sides of the impact load at different impact loads induced by changes in the impact velocity. In the vehicle sector, vertical and lateral forces of wheel-rail contact and lateral acceleration of the train bogie are obtained at the impact load of 8,700 kN considering the bridge plastic behavior. Finally, the results obtained from dynamic analysis of train-track-bridge interaction revealed train running safety indices exceed the allowed values specified by China Railway Regulations as the impact load exceeds 66 MN in terms of derailment factor and 4 MN in terms of offload factor.

In this paper, unidirectional (UG) and bidirectional (BG) density gradient equal-strength BCC (ES-BCC) lattice structures were designed and 316L stainless steel specimens were fabricated by selective laser melting (SLM). Deformation patterns and mechanical properties of these lattice structures under dynamic impact loads were investigated. The findings demonstrate that the specific energy absorption of UG (BG) could be increased by 14.54% (6.94%) and the average plateau stress by 110.93% (115.58%), compared to conventional BCC lattice structures with the same mass density. The density gradient design offers a novel approach and fresh perspective for lightweight, energy-absorbing lattice structures.