power..boost from,..and others..

microcantilevers are extremely versatile and are used as sensors and in many others microsystems. In this idea, simulik model of a microcantilever based actuator, which can be driven by nuclear radiation, is developed. This actuator can be used as micro-battery. Microcantilever tip portion is exposed to nuclear radiation from side and becomes charged because of emission of electrons from the radioactive element. thus, an electrostatic attractin is created between base and the cantilever tip, which gradually bends at the tip and discharges the electrons. Now, electrostatic attrction dissappears for a moment and then, the process repeats and thus the cantilever sests into oscillations. The piezoelectric plate on the microcantilever produces electric pulses, and can be used to generate electricity. In the electrical model, the force-vaoltage ( or mass-inductance ) analogy is considered The transfer function obtained is used to derive the system performance.Such microcantlevers offer an attractive power source for MEMS based actuators, which require high power density or long life. These microthingy may not replace chemical batteries but definitely they make a considerable change in power supply fr small electric gadjets.

The main idea behind the microbatteryas stated at above is microcantilever tip portion is exposed to nuclear radiation frm lower side as shown below :

Thereby its lower surface becomes negatively charged because of emission of electrons from the radioactive element underneath. Thus there is an electrostatic attraction between base and the cantilever ti. Once, sufficient number of electrons are collected, gradually the cantilever bends and discharges the electrons either by physical contact / tunneling / gas breakdown. Now electrostatic attraction dissappears for a moment and then, the process repeats and thus the cantilever sets into oscilations. This recurring mecahnical deformation of the piezoelectric plate kept on the microcantilever produces a series of electric pulses. These pulses can be rectified and smoothed to provide electricity. Considering the oscillating microcantilever as a system of a single degree of freedo formed by a body of mass as and spring of stiffness and a dashpot. The force-voltage analogy is considered as laplace transform of the derived equations as taken for solving and easy analysis of such MEMS as below :     
                                            Equivalent electrical circuit for a damp dynamic
                                           vibrating microcentilever with radiactive stimulus

 The laplace transform can be used to directly write the transfer function of the electrical equivalent.
                                                            Equivalent mechanical system

Assuming the cantilever such as silicon has negligible inertia, and the electrostatic force because of radiating particles leads to continous oscillations. the capacitance between cacntilever and base is given by equation as below :
                                                                      cantilever model

The spring force of the cantilever exactly balances the electrostatic attraction force on the centilever ( above )

Where K is the spring constant, Y is the initial distance, and yo is the changed distance. Assuming a uniform electric field, the capacitor can be modeled as a parallel plate capacitor C and the change on it is given by equation as below :

# im prefer MATLAB/simulink tool only


Post a Comment