BITS Faculty Publications
Permanent URI for this communityhttp://localhost:4000/handle/123456789/1867
Browse
4 results
Search Results
Item Investigations on a tapered flagellated nanoswimmer propelling through a helical wave(IEEE, 2015) Rathore, Jitendra S.Flagellar propulsion, observed extensively in nature has been proposed as a means of propelling nanoswimmers. The flagellum propels either through a planar wave or through a helical wave. In the present work, an elastohydrodynamic model of a tapered flagellum propelling through a helical wave with a modified resistive force theory is used to study the propulsive dynamics of a tapered flagellum. A tapered flagellum facilitates higher velocity and efficiency as compared to a uniform diameter flagellum. The optimal size, shape parameters and material for design have been investigated for the fastest and the most efficient nanoswimmer and simulations have been carried out for the prospective biocompatible materials for designing and realization of nanoswimmers.Item Nanoswimmer Energy Transduction System: Influence of Branching(Springer, 2018-10) Rathore, Jitendra S.Nanoswimmers are of interest among researchers for their utility in propelling nanorobots to specific target for drug delivery, nanosurgery, in vivo biomedical applications such as in treatment of brain tumor and Alzheimer’s disease and similar applications. On-board powering is the major concern for locomotion of nanoswimmer and is being considered to be addressed by energy transduction mechanism to harness energy from surrounding using energy of stochastic vibrations by electrostatic, electromagnetic, and piezoelectric means. Among all, piezoelectric is emerging as a promising conversion transduction mechanism of energy harnessing for artificial nanoswimmer. In this context, in present work, an elastic flagellum of a nanoswimmer is modeled as a cantilever beam and a simulation study is done in COMSOL. The novel design of branched flagellum is conceived, modeled, and simulated. COMSOL simulation studies have been performed to compare the effect of primary and secondary branching in flagellum design in terms of stress and electric potential. Enhancement in stress and electric potential is observed approximately 20 and 15% on increasing secondary branching uniformly on the main structure of cantilever beam towards free end and keeping primary branches constant. An enhanced stress allows for larger efficiency of conversion mechanism and, therefore, it is concluded that branching of flagellum can be pivotal in increasing on-board harnessing of energy for propulsion of nanorobots.Item Experimental investigation of biomimetic propulsion through a scaled up branched flagellated artificial nanoswimmer(Taylor & Francis, 2020-05) Rathore, Jitendra S.Locomotion of bacteria in fluid at small scale is accomplished by cilia and flagella present on its surface. In the present study, existence of cilia on Paramecium surface is mimicked to design scaled-up swimmer rather than utilising its biological function. In the present study, the branches (cilia) on flagella (Paramecium) is employed for designing of tail of an artificial nanoswimmer and experiments are performed at scaled-up level in silicon oil medium to maintain low Reynolds number. The effects of branches on generation of thrust force are investigated by fabricating the branched flagella using flexible polydimethylsiloxane biocompatible material suitable for human body and biological applications. The resulting data are quantitatively compared through statistical analysis. In the present research work, various designs of branched flagellated swimmer are fabricated by varying the number of branches and spacing between branches. Enhancement in thrust force is observed approximately 24% when number of branches is increased from 8 to 28. Therefore, it is concluded that branches on flagella play significant role in enhancement of thrust force for propelling nanoswimmer. Spacing between 8 branches flagella is also varied from 5 to 15 mm and percentage increase in thrust force is observed as 8.1%.Item Comparison of Piezo-material based Energy Transduction Systems for Artificial Nanoswimmer(IOP, 2018) Rathore, Jitendra S.The energy harnessing is a process of obtaining energy from the surrounding environment and converting into electrical energy. In the last two decades, there has been a plenteous study in energy harnessing. Now a day, energy harnessing using piezoelectric materials has drawn attention of researchers due to low cost, flexibility and light weight. The benefits of piezoelectric material can be utilized by designing a self-powered device for artificial nanoswimmer. Some of the ceramics which displays the piezoelectric effect are lead-zirconate-titanate (PZT), lead-titanate (PbTiO2), lead-zirconate (PbZrO3) and Barium Titanate (BaTiO3). PZT is most extensively used piezoelectric material in the field of energy harnessing but it is brittle in nature. Lead based piezoelectric materials are toxic in nature and may not suitable for in-vivo biomedical applications. To eradicate this problem, researchers are interested in synthesizing lead free piezoelectric material such as Aluminium Nitride (AIN), Barium Titanate (BaTiO3) and Polyvinylidenefluoride (PVDF). The biocompatibility of PVDF makes it appropriate to be used for energy harnessing in human body for applications like on board powering of nanoswimmer for various disease detection and drug delivery. In this paper, a cantilever beam is being simulated in COMSOL to study electric potential generated on the surface of beam made of different piezoelectric materials such as AIN, PVDF and PZT due to fluidic pressure, which will be utilized as energy for actuation of artificial nanoswimmer. Piezo-based cantilever beams have been compared and maximum electric potential is being observed in PVDF based beam. PVDF seems most promising piezoelectric material for in-vivo biomedical application and it is readily available.