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Incinerated precious stones such as diamond (InDia) are used in the Indian system of medicines to treat various diseases. More recently, they are used for treating tuberculosis and cancer related conditions. For the first time, we have performed the physico-chemical analysis and cell interaction studies for InDia. The hydrodynamic diameter of particles was found to be ~500 nm. The XRD pattern shows the crystalline nature of the material, with strong peaks at 2θ values of 43.77, 75.23 and 91.45, respectively. The hyperspectral-dark-field image shows the aggregation of the InDia particles inside the BV2 cells (microglial cells) and a change in the spectral profile with the particle's position within the cell. Our preliminary results suggest that, InDia particles are readily taken up by the BV2 cells and affect the cell's motility, without affecting their viability.

Fluid structure interaction (FSI) of Polydimethylsiloxane (PDMS) microcantilever under fluid flow was studied for air flow sensing application. 3x8x0.250 mm microcantilever was used for the study. A low speed mini wind tunnel which provides laminar flow inside the test section was used. The micro cantilever was subjected to fluid load with flow rate up to 360ml/s. COMSOL simulation was performed using FSI module to test the microcantilever deflection. It was found that the deflection of the microcantilever beam increases with increase in fluid flowrate. Experimental result are in agreement with simulation results.

The landing of an aircraft is one of the most critical operations because it directly affects the passenger safety and comfort. During landing, the aircraft fuselage undergoes excessive vibrations that cause the safety and the comfort problem and hence need to be suppressed quickly. A semi-active control system of a landing gear suspension by using Magnetorheological damper can solve the problem of excessive vibrations effectively. In this paper, a switching technique is developed in the simulation of the landing procedure which enables the system to switch from the single degree of freedom to three degrees of freedom system in order to simulate the sequential touching of the two wheels of the main landing gears and the nose landing gear wheels with the ground. A semi-active Magnetorheological damper is developed using two different controllers namely linear quadratic regulator and the H∞. Spencer model is used to predict the dynamic behavior of the Magnetorheological damper. The results of the designed controllers are compared to study the performance of the controllers in reducing the overshoot of the bounce response as well as the bounce rate response. The simulation results validated the improved performance of the robust controller compared to the optimal control strategy when the aircraft is subjected to the disturbances during landing.

Control of vehicle suspension systems has been the focus of extensive work in the past two decades. Many control strategies have been developed to improve the overall vehicle performance, including both ride quality and stability conditions. However, the concerns regarding the wheel motions affecting significantly on the handling and steering are ignored by researchers in the control formulation. A H ∞ control methodology is employed to design an active suspension system so that ride quality and wheel motions are improved simultaneously. In addition, a three-dimensional kinematic model of a specific suspension system, namely Macpherson suspension, is developed to study the alteration of those of kinematic suspension parameters which represent the wheel motions. The results show that the proposed robust design provides superior kinematic and dynamic performances compared to those of the passive system.

The present design introduces an optimized version of a microfluidics chip that uses dielectrophoresis phenomenon as a method of separation of the abnormal cells from the blood stream. Negative and positive dielectrophoretic forces (DEP) generated by a non-uniform electric field are engaged to separate the normal blood cells from the malignant ones. By fine tuning the parameters of the electric field different types of abnormal cells are isolated.

In this paper, a new nonlinear model of Macpherson strut suspension system for ride control applications is proposed. The model includes the vertical acceleration of the sprung mass and the motions of the unsprung mass subjected to control arm rotation. In addition, it considers physical characteristics of the spindle such as mass and inertia moment. This two degree-of-freedom (DOF) model not only provides a more accurate representation of the Macpherson suspension system for ride control applications but also facilitates evaluation of the kinematic parameters such as camber, caster and king-pin angles as well as track alterations on the ride vibrations. The performances of the nonlinear and linear models are investigated and compared. Simulation results are presented and discussed.

An analogy between the instabilities in electrostatic MEMS structures and aeroelastic aircraft wing structures has been inferred in this paper. The static and dynamic analysis of a simple mass-spring model of an electrostatically actuated MEMS structure is presented to understand the pull-in instability. Then the aeroelastic phenomenon occurring on the aircraft wing structures is explained with a simple one degree of freedom wing model. The divergence and flutter instabilities are studied. The control methods taken so far to counteract the instabilities in both cases have been discussed.

The pull-in voltage of an electrostatically actuated micro electro mechanical system (MEMS) is determined using the phase portrait analysis of the system. The velocity equation for a simple mass-spring model is derived and the phase portraits are presented. A continuous cantilever system is modelled as a lumped mass-spring system and the method of estimation of its equivalent stiffness, equivalent mass and equivalent areas are explained. The equilibrium positions are obtained from the force balance plot for different voltages and their corresponding conservative energy values are determined. The phase portraits are given for different voltages with their respective energy values from which the pull-in voltage is obtained for this system. This pull-in voltage value is in very close agreement with the previously published results for the same geometric and material parameters

This paper presents and applies the concept of micro-boundary conditioning to the design synthesis of microsystems in order to quantify the influence of non-classical support conditions on both static and dynamic behavior of microsystems.

Machinability is one of the important properties of a material. It is about cutting the material with maximum metal removal, in shortest time, with best surface finish while having maximum tool life. The high quality of surface finish is very important in order to face the required accuracy and marketing needs. In this paper we present a technique for modeling a machining process of Alumic-79 with 2 and 4-flutes cutting head. In this paper, optimum parameters, which are feed rate, spindle speed and depth of cut, are found for 2-flutes and 4-flutes cutting head to obtain a high quality surface finish.