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Research on tracked vehicle dynamics is by and large limited to multi-rigid body simulation. For realistic prediction of vehicle dynamics, it is better to model the vehicle as multi-flexible body. In this paper, tracked vehicle is modelled as a mass-spring system with sprung and unsprung masses of the physical tracked vehicle by Finite element method. Using the equivalent vehicle model, dynamic studies are carried out by imparting vertical displacement inputs to the road wheels. Ride characteristics of the vehicle are captured by modelling the road wheel arms as flexible elements using Finite element method. In this work, a typical tracked vehicle test terrain viz., Trapezoidal blocks terrain (APG terrain) is considered. Through the simulations, the effect of the road wheel arm flexibility is monitored. Result of the analysis of equivalent vehicle model with flexible road wheel arms, is compared with the equivalent vehicle model with rigid road wheel arms and also with the experimental results of physical tracked vehicle. Though there is no major difference in the vertical bounce response between the flexible model and the rigid model, but there is a visible difference in the roll condition. Result of the flexible vehicle model is also reasonably matches with the experimental result.

A review of available literature on machine tool transmission housings with specific reference to structural vibration, chatter analysis, and noise radiation is presented in this paper. Housings include gearboxes and structures supporting other transmission elements like vee pulleys, impellers, and motor shafts. Analytical and experimental methodologies reported in the recent past for strength, vibration and noise analysis, mounts and suspension, structural optimization, overall drive and housing systems are discussed. Typical design guidelines, as outlined by various investigators, are included. Future research trends are also indicated.

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The spray coating technique is used in this study to spread a thin layer of nanoparticle on a large flat substrate. The proposed spray coating techniques has a great potential for large scale productions, as these techniques have no restrictions on the substrate size and low utilization of the process parameters. In this study, a simple airbrush spray coating technique is used to deposit the multiwall carbon nanotubes (MWCNTs) on copper substrates with a decent deposition control. The microstructures, surface roughness, and wettability of the coated substrates were tested and compared with the pure copper substrates. The MWCNTs coated copper substrates exhibits a significant enhancement of the mechanical properties compared to the normal surface. The thickness of the copper substrates increases with increase in coating weight concentrations, the maximum thickness 1.43 microns achieved at 0.4 wt. % of MWCNTs. The usage of copper and MWCNTs based thin film signifies a inspiring but possibly a sustaining chance for developing the future generation heat transfer materials