Experimental investigation of Magneto-rheological damper

In recent years, intensive research works are concentrated on the development of semi-active control devices. A semi-active control system can also be explained as a system that mainly requires a small external power source for functioning and applies the motion of the structure to generate the control forces. A semi-active control system typically begins from a passive control system, which is followed by a change to permit the flexibility of mechanical properties. The mechanical properties of the semi-active control devices may be modified depending upon the response from the excitation and/or from the calculated reaction. Magneto-rheological (MR) dampers are a type of a semi-active control device that, in the presence of Magneto-rheological (MR) fluid, responds to the applied vibrations. This type of damper has copper winding in it, forming an electronic circuit internally with a combination of MR fluids. The effectiveness of MR damper greatly depends on the command voltage to the copper winding. In the present study, the response of MR Damper to the command voltage, and the excitation frequency is experimentally evaluated. MR damper is supported by a wall mounting rigid fixture and connected to a shake table by a fixing unit. The voltage is varied from 0 V - 10 V with an interval of 2 V. Command voltages is applied to the MR damper with the help of voltage regulator and digital multi meter. The effect of excitation frequency is also studied (1 Hz – 8 Hz). While conducting the experimental work, acceleration values are obtained through the Data acquisition system. These acceleration values are integrated to get the velocity and displacement response. The relation between the displacement, velocity, acceleration of the MR damper, and the frequency of shake table and command voltage is studied. From the experimental work, it is observed that the displacement response of the damper is effectively controlled by increasing the command voltage.