This paper reports on a study of the crankshaft torsional vibration phenomenon in internal combustion engines. The steady state of the state equation is solved by the transition state matrix and the convolution integral. This formulation is applied to the model of a sixcylinder diesel engine manufactured by MWM International Motores®. The analyses consider a rubber and viscous damper assembled to the crankshaft front-end. An analysis of the torsional vibrations indicates the dynamic loading on each crankshaft section, and these loads can be applied as boundary conditions in a finite element model to predict the safety factor of the component and to compare the system's behaviour with rubber and viscous damper options. This study highlights the importance of torsional vibration analyses in the structural dimensioning of crankshafts. The results of the torsional vibration amplitude are compared with measured values to experimentally validate the proposed mathematical model.

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Intelligent autonomous vehicles have received a great degree of attention in recent years. Although the technology required for these vehicles is relatively advanced, the challenge is firstly to ensure that drivers can understand the capabilities and limitations of such systems and secondly to design a system that can handle the interaction between the driver and the automated intelligent system. In this study, we describe an approach using different strategies for an autonomous system and a driver to drive a vehicle cooperatively. The proposed strategies are referred to as cooperative planning and control and determine when and how the path projected by the autonomous system can be changed safely by the driver to a path that he wishes to follow. The first phase of the project is described, covering the design and implementation of an autonomous test vehicle. Experiments are carried out with a driver to test the cooperative planning and control concepts proposed here.

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The concept of reconfigurable magnetic coupling thrusters (RMCT) applied to the vectorial thrust of autonomous underwater vehicles (AUV) has been recently developed and presented. This technology ensures greater robot watertightness with enhanced maneuvering capabilities, which are desired features in agile AUVs for marine renewable energy (MRE) system maintenance. It is possible since in RMCTs the driving torque is magnetically transmitted to the propeller, which has its orientation changed. This work is focused on the coupling and control torque calculation and further analysis of the latest prototype version (Flat-RMCT), in the static condition for the full thrust vector range. For this purpose, a numerical model is implemented and validated with experimental results. The numerical model is based on the finite volume integral method. The results indicate that the minimum magnetic reluctance propensity creates not only the expected magnetic spring effect but also an auto-driving torque due to the non-axial symmetry of coupling rotors, which exists only for reconfigurable couplings. Mathematical functions are proposed to model these effects and they are used to extend the understanding of the coupling. These models can be used to compose a full and accurate dynamic model for a better RMCT simulation, identification, and control.