Energy scavenging from insect flight

This paper reports the design, fabrication and testing of an energy scavenger that generates power from the wing motion of a Green June Beetle (C otinis nitida ) during its tethered flight. The generator utilizes non-resonant piezoelectric bimorphs operated in the d 31 bending mode to convert mechanical vibrations of a beetle into electrical output. The available deflection, force, and power output from oscillatory movements at different locations on a beetle are measured with a meso-scale piezoelectric beam. This way, the optimum location to scavenge energy is determined, and up to ~115 µW total power is generated from body movements. Two initial generator prototypes were fabricated, mounted on a beetle, and harvested 11.5 and 7.5 µW in device volumes of 11.0 and 5.6 mm 3 , respectively, from 85 to 100 Hz wing strokes during the beetle's tethered flight. A spiral generator was designed to maximize the power output by employing a compliant structure in a limited area. The necessary technology needed to fabricate this prototype was developed, including a process to machine high-aspect ratio devices from bulk piezoelectric substrates with minimum damage to the material using a femto-second laser. The fabricated lightweight spiral generators produced 18.5–22.5 µW on a bench-top test setup mimicking beetles' wing strokes. Placing two generators (one on each wing) can result in more than 45 µW of power per insect. A direct connection between the generator and the flight muscles of the insect is expected to increase the final power output by one order of magnitude.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90804/1/0960-1317_21_9_095016.pd

A study of energy scavenging strategy in a tapping tree power

Energy harvesting has become one of the newest research attraction for both academic and industry fields. The energy is captured from external sources (thermal, wind, solar, vibration and hydrodynamic) and the energy source for energy harvesters is present as ambient background and it is free. The energy can be harvested in term of sensors or direct applying which depends on the source applied to. One of the energy harvesting topologies is from tapping tree which is new topology that can be applied direct to the tree by inserting electrode into the tree while the other is into the surrounding soil. This project introduces a method for the energy to be harvested from a tree, where the voltage obtained is conducted to three types of trees (Palm, Agrawood, and Palm Oil). Both type of electrodes and pH value of the surrounding soil are considered in order to get maximum voltage. Furthermore, the depth of the electrode inserted and the height from the surrounding soil play a role for voltage variation. The maximum voltage can be obtained is from (Al Alloy with Al) electrodes, at neutral pH, dry mositure and in Palm Oil Tree which is almost 0.8V - 1.2V. However, at such small energy from tree source, converter is required to increase the power. Boost converter contains of BQ25504 IC is applied to increase the voltage from small input to 3V - 4V. As well as, buck converter with TPS62231 IC is introduced for the output voltage of the boost converter and can be applied for small voltage as 1.8V. Simulation using Tina software simulate the converters mentioned and get better results for the energy harvested with battery charging system and energy storage. Field test is conducted with the selected converter to insure the power observed from the plant. In addition, this work has been taken to enhance the growth of energy harvesting from small sources and to go further for nature sources that has a high impact for low applications in the future

Energy scavenging system for indoor wireless sensor network

As wireless communication evolves wireless sensors have begun to be integrated into society more and more. As these sensors are used to a greater extent newer and better ways to keep them working optimally have begun to surface. One such method aims to further the sensors energy independence on humans. This technique is known as energy scavenging. The logic behind energy scavenging is to allow the device to have its own reliable source of energy that does not require upkeep, has a long life expectancy, and does not completely rely on an internal power source. The aim of this thesis is to research techniques for indoor energy scavenging for sensor that is used to monitor patients in a hospital. There are numerous techniques to achieve energy scavenging in wireless sensor networks. Multiple scavenging methods are known such as vibration energy, thermoelectric energy, and photovoltaic energy. All of these methods were analyzed and compared to see which would be optimal for the situation the sensor would be put in. Other techniques come into play to help the efficiency of the sensor network. These methods were also examined to help the energy scavenging to be more feasible

A complete study of electroactive polymers for energy scavenging: modelling and experiments

Recent progresses in ultra low power microelectronics propelled the development of several microsensors and particularly the self powered microsystems (SPMS). One of their limitations is their size and their autonomy due to short lifetime of the batteries available on the market. To ensure their ecological energetic autonomy, a promising alternative is to scavenge the ambient energy such as the mechanical one. Nowadays, few microgenerators operate at low frequency. They are often rigid structures that can perturb the application or the environment; none of them are perfectly flexible. Thus, our objective is to create a flexible, non-intrusive scavenger using electroactive polymers. The goal of this work is to design a generator which can provide typically 100 ?W to supply a low consumption system. We report in this paper an analytical model which predicts the energy produced by a simple electroactive membrane, and some promising experimental results.Comment: Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/EDA-Publishing

Hybridization of Magnetism and Piezoelectricity for an Energy Scavenger based on Temporal Variation of Temperature

Autonomous microsystems are confronted today to a major challenge : the one of energy supply. Energy scavenging, i.e. collecting energy from the ambient environment has been developed to answer this problematic. Various sources have already been successfully used (solar, vibration). This article presents temporal variations of temperature as a new source of exploitable energy. A brief review will take place at the beginning, exposing the different approaches used in the past. Then we will focus our attention on hybridization of magnetism and piezoelectricity. A new kind of thermal generator is proposed and a preliminary model is exposed. Conclusions will be drawn on the suitability of this prototype and the improvements that are needed to increase its potential.Comment: Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/handle/2042/16838

Freshman Engineering Project on Energy Scavenging

This paper describes the design, development and implementation of an energy scavenging project for an introduction to engineering course. The overall objective of the project is to provide students with a hands-on experience on all the components of a renewable energy system. After completing this project students should be able to understand the basic engineering concepts as well as the principles of the design process. Energy scavenging is a form of renewable energy technology at micro or nano scale level. In this project students design and build a small vibrating system that takes the place of the energy source. A piezoelectric material is used to collect the energy produced by the vibrating system. The output of the piezoelectric material is fed to a rectifier circuit whose output charges a battery. Over two hundred freshman engineering students from four different disciplines: civil, computer, electrical, and mechanical have completed this project. Students’ reports, reflection papers, and the results from surveys clearly show that, in addition to be a very appealing project, its objectives are achieved