Simulation of spiral-shaped mems human energy harvester using piezoelectric transduction

Energy harvesters are one of the focus areas in the field of research. The complex smart devices and miniaturized electronic design limit the use of traditional wired power source. The need for an efficient human energy harvester for such devices is growing exponentially every year due to an increase in the demand of energy sources and power requirement for the electronics. In the recent years, the trend of research is leading us to come up with a better solution of replacing the use of non-renewable energy with the renewable sources. Human energy harvesting technique has evolved as an efficient substitute to these. But there are few challenges in designing such energy harvesters. Firstly, obtaining higher efficiency. Moreover, since the efficiency is lower it is difficult to obtain enough energy considered to size. The goal is to model and simulate small scale energy harvester which harvests the ambient energy efficiently. There are several advantages of human energy harvester which make it beneficial, cost-effective and has grabbed the attention of researchers since past several years. In this thesis report, a human energy harvester has been designed in a 2-loop spiral design and simulated to obtain an efficient design using piezoelectric materials.Includes bibliographical reference

Magnetocapillary self-assemblies: locomotion and micromanipulation along a liquid interface

This paper presents an overview and discussion of magnetocapillary self-assemblies. New results are presented, in particular concerning the possible development of future applications. These self-organizing structures possess the notable ability to move along an interface when powered by an oscillatory, uniform magnetic field. The system is constructed as follows. Soft magnetic particles are placed on a liquid interface, and submitted to a magnetic induction field. An attractive force due to the curvature of the interface around the particles competes with an interaction between magnetic dipoles. Ordered structures can spontaneously emerge from these conditions. Furthermore, time-dependent magnetic fields can produce a wide range of dynamic behaviours, including non-time-reversible deformation sequences that produce translational motion at low Reynolds number. In other words, due to a spontaneous breaking of time-reversal symmetry, the assembly can turn into a surface microswimmer. Trajectories have been shown to be precisely controllable. As a consequence, this system offers a way to produce microrobots able to perform different tasks. This is illustrated in this paper by the capture, transport and release of a floating cargo, and the controlled mixing of fluids at low Reynolds number.Comment: 10 pages, 8 figures review pape

Spatially-varying multi-degree-of-freedom electromagnetic energy harvesting

This work presents the theoretical modelling of a novel spatially varying multi-degree of freedom electromagnetic vibration energy harvester(EMVEH) that integrates two novel strategies of energy harvesting - the spatial variation of the magnetic field and the design of multi-degree of freedom energy harvesters thus making a very versatile electromagnetic energy harvester model. The EMVEH models were theoretically formulated using analytical and numerical simulation and then followed by experimental validation

Development and Characterization of an Aeroelastic Instability Energy Harvester

Development of new renewable energy sources has become paramount in the battle againstrising energy consumption and prices, environmental destruction, and global climate change.However, prior research efforts have indicated an aeroelastic instability energy harvester(AIEH) is capable of generating more than 70 mW of power at 4 mph wind (below thecut-in speed of any wind turbine). The AIEH has shown an enhancement in performancein the presence of a bluff body (contrary to turbines) and a non-linear increase in powerproduction with an increase in wind speed. It also allows the consumer to choose the extentof investment cost (less than $50 for parts), with minimal maintenance cost. The intent ofthis thesis work is to gain a better understanding of AIEHs in a number of different ways:characterizing the limit-cycle oscillation (LCO) experienced by an AIEH; validating the beliefthat an active smart material may enhance the power density of an AIEH; validating andcharacterizing the enhanced performance exhibited by AIEHs in the presence of a bluff body.In the short term AIEHs are expected to be of particular utility for powering remote civilinfrastructure sensor systems. In the long term they may have the potential to become aviable, new, renewable energy technology with power generation levels appropriate to societalenergy needs. Also, its relatively low investment and maintenance cost has the potential tomake this technology ideal for third world applications