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The rollover problem had a great concern in the last few years, where various mathematical models for vehicle rollover were developed. The main parameters that are essentials for assessment of vehicle rollover are suspension stiffness, shock absorber damping, and tire stiffness and damping in addition to vehicle weight and geometry. It is a difficult task to change these parameters during a real vehicle dynamic testing. Moreover, such dynamic test is almost a destructive one due to severity of rollover crashes [ 1 ]. Also, a real vehicle dynamic testing has many disadvantages which cannot be easily avoided such as the effect of driver behavior, the cost of instrumentation and equipment, time consumption, and effect of outriggers on the vehicle roll mass moment of inertia. In the present paper, the adoption of a scaled vehicle lab model (VLM) to study the effect of design parameters on vehicle rollover instead of destructive vehicle dynamic testing has shown its validity.

The aim of this paper is to present two widely used techniques in gearbox diagnostics through implementation of these techniques on a heavy duty truck with two types of local faults, broken teeth and defected bearing. The first technique presented in this study is the stationary STSF (Spatial Transformation of Sound Field) which is based on the measured acoustic signal captured in the nearfield of the operating gearbox. The second technique is the Vibroacoustic technique which is based on the vibration signal picked up on the gearbox surface. The results from acoustic signals were compared with vibration signals. In contrast to Vibroacoustic technique, unless special methods and particular arrangement are used to reconstruct the acoustic field, STSF may suffer from some difficulty and limitations. Also, background noise or any acquisition errors may result in an erroneous reconstruction of the acoustic quantities.

Vibration energy harvesters are considered as green and sustainable power supply for wireless sensor networks (WSN) used in different vehicle applications. Kinetic energy from ambient vibration is typically converted into electrical energy using electromagnetic, piezoelectric or electrostatic transducers. In comparison with other harvesters, electromagnetic transducers enable design of high power (few mill watts) low frequency (tens of Hz) harvesters. Electromagnetic harvesters can be considered as a power source for wireless sensor networks used for vehicle electronic devices. This paper demonstrates theoretically and experimentally the design procedures of electromagnetic harvesters of mechanical vibrations emitted from car engine. The research in this paper is concerned with the modeling, designing, and testing of the vibration energy electromagnetic harvesters that should be mounted on car engine.