Everything in the universe that has mass possesses stiffness and intrinsic damping. Owing to the stiffness property, mass will vibrate when excited and its intrinsic damping property will act to stop the vibration. The particle impact damper (PID) is a very interesting damper that affects impact and friction effects of particles by means of energy dissipation. PID is a means for achieving high structural damping by using a particle-filled enclosure attached to a structure. The particles absorb the kinetic energy of the structure and convert it into heat through inelastic collisions between the particles themselves and between the particles and the walls of the enclosure. In this work, PID is measured for a cantilever mild steel beam with an enclosure attached to its free end; copper particles are used in this study. The PID is found to be highly nonlinear. The most useful observation is that for a very small weight penalty (about 7% to 8 %), the maximum damped amplitude of vibration at resonance with a PID, is about 9 to 10 times smaller than that without a PID. It is for more than that of with only intrinsic material damping of a majority of structural metals. A satisfactory comparison of damping with and without particles through experimentation is observed. The effect of the size of the particles on the damping performance of the beam and the effective packing ratio can be identified. It is also shown that as the packing ratio changes, the contributions of the phenomena of impact and friction towards damping also change. It is encouraging that despite its deceptive simplicity, the model captures the essential physics of PID.

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This paper aims at experimental analysis of composite box beam to estimate the material uncertainty. The deflection parameter has considered for analyzing the uncertainties present in material. The composite box beam is like a cantilever beam, where one end is fixed and at free end load is applied. In previous study free end deflection is calculated using Dial Gauges whose stylus will make point contact with proposed setup. But due to this contact it will create instrumental errors or manual error during experimentation. To avoid such situation the non contact device is developed called as Hall Effect Sensor which is the electronic device and it is works on electromagnetic field. If magnet is come in front of sensor it create magnetic field between them. The change in voltage or field is calibrated in terms of deflection of beam. In this paper, experimentation has carried out on four composite box beams which are manufactured by same process to find the material uncertainties and then the results are validated with COMSOL Multiphysics, software for same parameters.

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