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Academic literature on the topic 'Harvesters'

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Published: 4 June 2021
Last updated: 14 February 2022

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Journal articles on the topic "Harvesters"

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Yarborouph, David E. "A COMPARISON OF THREE MECHANICAL HARVESTERS AND HANDRAKING FOR WILD BLUEBERRIES." HortScience 27, no. 6 (June 1992): 600d—600. http://dx.doi.org/10.21273/hortsci.27.6.600d.

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Hand raking was compared to a non-mechanized machine and to two self propelled harvesters for yield and harvest time. Experimental design was split-plot replicated six times with four harvesters/plot with each raker using each machine in each plot. The machines were operated adjacent to one another. Hand raking resulted in the highest yield recovery of all harvesters. Average yield varied by raker from a high of 4831 kg/ha to a low of 3884 kg/ha. The Bluevester harvester recovered 91% of hand harvest and was 1.6 times faster than hand raking while the Darlington machine harvested one half of hand harvest in one quarter of the time. The Easy Pick recovered 81% of hand harvest but was twice as fast. Mechanical harvesters took less time but recovered fewer berries. A economic analysis is needed to fully evaluate these machines.
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Astafyev, V. L., and E. V. Zhalnin. "Efficiency Evaluation of Grain Harvesters of Different Types under North Kazakhstan Conditions." Agricultural Machinery and Technologies 12, no. 3 (July 26, 2018): 17–21. http://dx.doi.org/10.22314/2073-7599-2018-12-3-17-21.

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The problem of selecting certain types of grain combine harvesters is quite urgent now. This is because the agricultural manufacturers are struggling to make a right selection of a grain harvester of a definite firm or make due to the aggressive marketing from the manufacturers. (Research purpose) Efficiency evaluation of grain harvesters of different types under the North Kazakhstan weather conditions. (Materials and methods) Technical and economic research has been performed according to the standard methodology followed by data analysis. The calculation has been made for direct combining by 4, 5 and 6­-class harvesters equipped with wide­cut headers from leading domestic and foreign manufacturers. (Results and discussions) the authors have also calculated direct costs for thrashing of one ton of grain under favorable harvesting conditions, total costs for thrashing of one ton of grain including grain losses under unfavorable harvesting conditions, as well as total costs for thrashing of one ton of grain considering that 30% of grain is harvested under favorable harvesting conditions and 70% -­ under the ones. (Conclusion) It has been found that the price of thrashing of one ton of grain that characterizes the efficiency of utilizing grain harvesters depends on the price/efficiency ratio of a harvester, yield and harvesting conditions. Combine harvesters of a lower class with the optimum price/efficiency ratio are more preferable under favorable harvesting conditions. However, in case of the harvest period prolongation due to unfavorable harvesting conditions, combine harvesters of a higher class are more preferable.
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Malaji, P. V., Suresh Doddi, Michael I. Friswell, and Sondipon Adhikari. "Analysis of pendulums coupled by torsional springs for energy harvesting." MATEC Web of Conferences 211 (2018): 05008. http://dx.doi.org/10.1051/matecconf/201821105008.

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Harvesting energy from ambient sources has been a recent topic of interest. A typical linear harvester is effective only near resonance, limiting its frequency bandwidth. In order to increase the efficiency and bandwidth of harvesters, various strategies have been proposed. Using multiple harvesters in a single device can harvest enough power over wider frequency band. In the present work, the effect of torsional coupling of the harvesters for low frequency vibration energy harvesting is investigated. Two pendulums with electromagnetic induction as the energy conversion mechanism is proposed. The performance of the device is studied theoretically and numerically. Cubic polynomials are used to model the pendulum nonlinearity. Fundamental harmonic oscillation are assumed to obtain the analytical solution. The effect of torsional coupling and pendulum length on the power harvested are reported.
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Novák, Pavel, and Patrik Burg. "Evaluation of harvest losses within a full mechanised grape harvest." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 61, no. 3 (2013): 751–56. http://dx.doi.org/10.11118/actaun201361030751.

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A contribution deals with an evaluation of harvest losses within a full mechanised berries harvest using two self-propelled harvesters GREGOIRE G 152 and NEW HOLLAND VL 6060 differing in kinds of harvesting and catching mechanisms. Observation was done in vineyards of ZVOS Hustopeče joint–stock company at harvest of Müller Thurgau and Lemberger varieties in a period 2009–2010. Results gained under operating conditions showed that both self-propelled harvesters reached a comparable quality of a harvested product. There were observed losses by a slump in a case of using GREGOIRE G 152 harvester 0.8–1.45%. By using NEW HOLLAND VL 6060 the losses were 0.86–1.52% and data were gained with a respect to vine condition, the variety and the vintage. Next to losses by the slump also losses as non-harvested product were observed. Using GREGOIRE G 152 were reached 1.08–2.56% of non-harvested product losses and in a case of NEW HOLLAND VL 6060 similarly 1.17–2.22%. However a value of the non-harvested product losses cannot be perceived absolutely because in a practice the non-harvested grapes are consequently picked up manually. Total losses perceived as a sum of losses by the slump and non-harvested losses values were at GREGOIRE G 152 harvester 2–4% and at NEW HOLLAND VL 6060 harvester 2–3.7% of total hectare yield.
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Yarborough, David E. "A Reevaluation of Mechanical Harvester vs. Hand-raking for Wild Blueberries." HortScience 30, no. 4 (July 1995): 800F—800. http://dx.doi.org/10.21273/hortsci.30.4.800f.

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Improvements in the Bragg harvester and the introduction of a new Nimco harvester warranted a reevaluation of new technologies. Four technologies: the Bragg harvester, a modified Bragg harvester, the Nimco prototype, and hand-harvesting were evaluated at two locations: a land-leveled field (T-19) and a field without land leveling (Deblois). The experimental design was a randomized complete block with eight replications. A 150-ft strip was harvested with each technology, with strips directly adjacent to each other to minimize field variability. Time to harvest and berry weights were measured. Poor maintenance, adjustment and skill of the operator contributed to a 69% recovery relative to hand-harvest by both the Bragg and modified Bragg harvesters. The Nimco harvester has great potential, but only if it is properly mounted to allow it to cover the fields at a speed similar to the Bragg harvesters. The land-leveled field allowed for greater recovery for the Bragg and Nimco harvester, indicating that smoother fields are more efficient for machine-harvesting.
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Shan, Xiaobiao, Haigang Tian, Han Cao, Ju Feng, and Tao Xie. "Experimental Investigation on a Novel Airfoil-Based Piezoelectric Energy Harvester for Aeroelastic Vibration." Micromachines 11, no. 8 (July 26, 2020): 725. http://dx.doi.org/10.3390/mi11080725.

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This paper presents a novel airfoil-based piezoelectric energy harvester (EH) with two small square prisms attached to an airfoil. This harvester can achieve a two degree-of-freedom (DOF) plunge–pitch motions. Several prototypes of energy harvester were fabricated to explore the nonlinear aerodynamic response and the output performance in a wind tunnel. The experimental results showed that the longer the flexible spring was, the lower the critical velocity and frequency of the harvester were, and the better aerodynamic response and output performance could be achieved. The initial disturbance, the following limit-cycle oscillation, and the ultimate chaos of nonlinear response occurred, as increasing airflow velocity was increased. The overall output performance of the harvesters with a flexible spring having a thickness of 1 mm outperformed than that of the harvesters with a flexible spring having a thickness of 0.5 mm at a higher airflow velocity, while the tendency was opposite at a lower velocity. An optimum output voltage of 17.48 V and a power of 0.764 mW were harvested for EH-160-1 at 16.32 m/s, which demonstrated it possessed better performance than the other harvesters. When the capacitor was charged for 45 s and directly drove a sensor, it could maintain working for 17 s to display temperature and humidity in real time.
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Pajic, Milos, Vesna Pajic, Sanjin Ivanovic, Mico Oljaca, Kosta Gligorevic, Dusan Radojicic, Milan Drazic, and Ivan Zlatanovic. "Influence of harvester type and harvesting time on quality of harvested chamomile." Journal of Agricultural Sciences, Belgrade 61, no. 2 (2016): 201–13. http://dx.doi.org/10.2298/jas1602201p.

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This paper is the result of studying effects of mechanical chamomile harvesting on yield and quality of harvested chamomile. Chamomile (Chamomilla recutita (L) Rausch.) was harvested at three time intervals (T1 - 240 days, T2 - 250 days and T3 - 260 days after sowing) by three conceptually different harvesters. The results achieved indicate that the harvester type significantly influences quality of harvested chamomile, whereas it is not influenced by chamomile harvesting time. Quality of harvested chamomile was classified into four categories, and it was observed that the greater number of rotations of a picking device increased the content of the first category of quality. The harvester A achieved 54.79% of the first category of quality in respect to the harvester B achieving 50.26% and the harvester C with 42.93%.
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Sirén, Matti, and Hannu Aaltio. "Productivity and Costs of Thinning Harvesters and Harvester-Forwarders." International Journal of Forest Engineering 14, no. 1 (January 2003): 39–48. http://dx.doi.org/10.1080/14942119.2003.10702468.

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Masoumi, Hamidreza, Hamid Moeenfard, Hamed Haddad Khodaparast, and Michael I. Friswell. "On the Effects of Structural Coupling on Piezoelectric Energy Harvesting Systems Subject to Random Base Excitation." Aerospace 7, no. 7 (July 4, 2020): 93. http://dx.doi.org/10.3390/aerospace7070093.

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The current research investigates the novel approach of coupling separate energy harvesters in order to scavenge more power from a stochastic point of view. To this end, a multi-body system composed of two cantilever harvesters with two identical piezoelectric patches is considered. The beams are interconnected through a linear spring. Assuming a stochastic band limited white noise excitation of the base, the statistical properties of the mechanical response and those of the generated voltages are derived in closed form. Moreover, analytical models are derived for the expected value of the total harvested energy. In order to maximize the expected generated power, an optimization is performed to determine the optimum physical and geometrical characteristics of the system. It is observed that by properly tuning the harvester parameters, the energy harvesting performance of the structure is remarkably improved. Furthermore, using an optimized energy harvester model, this study shows that the coupling of the beams negatively affects the scavenged power, contrary to the effect previously demonstrated for harvesters under harmonic excitation. The qualitative and quantitative knowledge resulting from this analysis can be effectively employed for the realistic design and modelling of coupled multi-body structures under stochastic excitations.
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Machado, Túlio de A., Haroldo C. Fernandes, Clarice A. Megguer, Nerilson T. Santos, and Fabio L. Santos. "Quantitative and qualitative loss of tomato fruits during mechanized harvest." Revista Brasileira de Engenharia Agrícola e Ambiental 22, no. 11 (November 2018): 799–803. http://dx.doi.org/10.1590/1807-1929/agriambi.v22n11p799-803.

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ABSTRACT The use of mechanization in the harvesting of industrial tomatoes provides greater yield and speed of this stage. However, mechanical intervention in this process may alter the physiology of harvested fruits. Therefore, the objective of this study was to measure the quantitative losses of tomato fruits and to verify the physico-chemical behavior of fruits harvested based on physicochemical analysis in harvesters with different hours of use. Three self-propelled harvesters of the same brand and model with different working hours were used. Manually selected or undamaged fruits were harvested; afterwards, mechanized harvesting was carried out. Firmness, titratable acidity, soluble solids content (°Brix), pH, weight loss and fruit status classification proposed by the Ministry of Livestock, Agriculture and Food Supply of 2002 were evaluated. Quantitative losses were divided into: losses on vines, losses on soil and total losses. It was found that the number of hours worked by the harvester did not affect the quantitative losses. The amount of overall damage in a certain amount of fruit is greater when the harvester has a greater number of hours worked. Mechanized harvesting affected the physical attributes of the fruits, such as firmness and percentage of weight loss.
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Dissertations / Theses on the topic "Harvesters"

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Sun, Huihui. "Miniature wind energy harvesters." Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/416874/.

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Energy harvesting is a very attractive technique for a wide variety of self-powered microsystems such as wireless sensors. Airflow induced oscillations have been used as an attractive technique for energy harvesting because of its potential capacity for generating electrical power. The aero-elastic instability phenomenon such as flutter has been suggested especially for small scale energy harvesters. This paper describes the design, simulation, fabrication, measurement and performance of a miniature wind energy harvester based on a flapping cantilevered beam. The wind generator is based on oscillations of a cantilever that faces the direction of the airflow. The oscillation is amplified by interactions between an aerofoil attached on the cantilever and a bluff body placed in front of the aerofoil. To achieve the optimum design of the harvester, both computational simulations and experiments have been carried out to investigate the structure. Simulation is achieved with ANSYS to optimise the structure and predict the power generation for practical design. Both piezoelectric materials and electromagnetic transducers are used for the generator and tested. Three prototypes with the same volume of 37.5 cm3 are fabricated and tested through two aspects of the performance namely the threshold wind speed for operation and the output power. Wind tunnel test results are presented to determine the optimum structure and to characterize the performance of the harvesters. The piezoelectric generator is fabricated by thick-film screen printing technique. The optimized device finally achieved a working wind speed range from 2 m/s to 8 m/s. The power output was ranging from 0.35 to 3.6 μW and the open-circuit output voltage was from 0.6V to 1.9V. The first electromagnetic harvester had a working wind speed range from 1.35 m/s to 6 m/s with a maximum power output of 29.8 μW and a voltage of 293 mV. While for the second generator, the wind speed for operation is form 1.5 m/s to 6.5 m/s. The output power is ranging from 8.9 μW to 41 μW and the output voltage is up to 171 mV. Results verified the harvester can effectively convert wind energy into large amplitude mechanical vibration without strict frequency matching constraints.
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Simeone, Luigi. "Nonlinear damping in energy harvesters." Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/426890/.

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Energy harvesting from ambient vibration has become an attractive topic in the recent years. Initial studies aimed to maximise the performance of small linear device for different excitation scenarios. These devices were assumed to be located in hostile and inaccessible environments and be able to provide energy for low powered sensors. Due to the limited size of the energy harvesters, however, the amount of power produced was small. More recently, many researchers have considered using nonlinear stiffness to improve the performance of these devices. This thesis, however, focuses on the use of nonlinear damping in energy harvesters. Nonlinear damping may be unwanted and introduced as the mechanism of the harvester, but can also be deliberately introduced to improve the dynamic range of the harvester. Typically ambient vibration generates a relative displacement between the suspended mass and the base in an energy harvester, which induces an electromotive force (EMF) in a circuit that is used to harvest electrical energy. It is possible to introduce nonlinear mechanical damping by having a circuit with a nonlinear resistance. Specifically, a load, in which the current is a third-power function of the voltage is compared with an equivalent linear load for three kinds of excitation such as harmonic, random white noise and random bandlimited noise. According to the numerical and analytical results, the cubic load provides more harvested power at resonance at low levels when compared to an equivalent linear load at the same level of excitation. As the frequency bandwidth of a random excitation becomes wider, to the limit of white noise, as the power generated by the cubic converges to the linear case. Electromagnetic transducer energy harvesters usually adopt a conversion mechanism of motion, such as ball screw or rack and pinion, which introduce a source of loss such as friction. Static friction is then added to the model and this is shown to affect the harvested power at low input levels. Another proposed strategy consists of adjusting the electric load according to the input level, which can also enlarge the dynamic range of performance of energy harvested compared to a device with constant load. To demonstrate the effectiveness of the level-dependent load, an energy harvesting device was designed and manufactured, which comprised of an oscillating beam sprung to the base, and attached to a generator. Across the terminals of the generator, an electric resistance is mounted and the voltage measured is used to compute the harvested power. Experiments are conducted by exciting the harvested with a harmonic input at resonance via a shaker. A level-dependent load and a constant load were separately tested; with results that are in good agreement with the simulations, it is shown that by adjusting the load according to the input level, the harvested power is increased compared to a linear constant load.
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Hogue, Daniel B., and Sarah M. Gregory. "MEMS-based waste vibrational energy harvesters." Monterey, California: Naval Postgraduate School, 2013. http://hdl.handle.net/10945/34678.

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Approved for public release; distribution is unlimited
The piezoelectric effect is a phenomenon where strain on a piezoelectric crystal structure causes potential difference at its ends. By merging piezoelectric materials and microelectromechanical systems (MEMS), mechanical vibration could cause the necessary displacement in MEMS to create a potential difference that could be used to power electronic devices. Developing new sustainable energy sources and using energy more efficiently is at the forefront of several research initiatives and is a clear priority for the Department of the Navys strategic planning. This thesis aims to design a vibrational energy harvesting MEMS device to harness vibrational waste energy with the goal of producing power for naval applications. The development and widespread use of vibrational harvesting MEMS would aid the effort to meet each of these goals in the Department of the Navy. Any shore based, seagoing, or expeditionary mechanical platform could serve as a kinetic energy source for vibration energy harvesting MEMS. This thesis investigates the physics, materials, design, optimization, and microfabrication process in the creation of such a device. Time-dependent finite element models for two designs have been developed, simulating electrical power output. Microfabrication processes for the designs have also been developed.
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Jalali, Nimra. "ZnO nanorods-based piezoelectric energy harvesters." Thesis, Queen Mary, University of London, 2015. http://qmro.qmul.ac.uk/xmlui/handle/123456789/8948.

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Piezoelectric nanostructures of ZnO were employed for development of vibration energy harvesters. Columnar nanorod structures of ZnO, incorporated into various heterojunction-based device prototypes, were strained to generate voltage signals. The fabricated devices’ prototypes were based on different top electrodes such as: p-n junction-type Poly(3,4-ethylenedioxythiophene) Polystyrene sulfonate (PEDOT:PSS)/ZnO devices, metal-insulator-semiconductor type Poly(methyl methacrylate) (PMMA)/ZnO devices. Similarly, various bottom electrode materials based prototypes were also assembled: ZnO/indium tin oxide (ITO), ZnO/silver (Ag) and ZnO/zinc (Zn). The overall device design was based on flexible electrodes and substrates, due to which low temperature (below 100 °C) fabrication processes were implemented. Device performance measurement and characterisation techniques were explored and implemented to improve the reliability of results. These techniques included open-circuit voltage and short-circuit current output measurement, resistive load matching and impedance analysis. The analysed performance of energy harvester was assessed in relation to its constituent material properties. The parameters which affect the energy harvester performance were investigated and for this p-n junction-based (PEDOT:PSS/ZnO) devices were used. It was analysed that devices with optimum shunt (Rsh) and series resistance (Rs), which were in the ranges of 0.08 – 0.17 kΩ and 0.5 – 1.65 kΩ respectively, generated the highest peak open-circuit voltage (Voc) and peak power density (PL) of 90 – 225 mV and 36 – 54 μW cm-2. However, the p-n junction-based devices with low shunt resistance (Rsh), ranged between 0.2 – 0.3 kΩ, were considered to be affected with leakage losses, such as short-circuits. Therefore, these devices generated lower Voc and PL in the range of 20 - 60 mV and 2 - 16 μW cm-2. Similarly, the p-n junction-based devices with higher Rs, ranged between 0.3 – 0.6 kΩ, were adversely affected by I2R losses and therefore their generated power density was also dropped to 0.22 - 0.25 μW cm-2. In addition to parasitic resistance losses, the most significant phenomenon investigated in ZnO energy harvesters was, screening of polarisation ii charges in ZnO. The polarisation screening effects were observed to be related to the electrical properties of device components like electrode material type and conductivity of ZnO. Hence, the effect of electrode electrical properties on electric field screening was investigated. In this regard, device electrodes were varied and their effect on energy harvesting efficiency was studied. A comparison based on the performance of bottom electrodes like indium tin oxide (ITO), silver (Ag) and zinc foil on device performance was made. It was observed that due to lower screening effects of ITO, the ITO-based devices generated voltage output which was two orders of magnitude higher than the zinc foil-based devices. Similarly, the screening effects of top electrode materials, like PEDOT:PSS and PMMA, on device output generation were investigated. The PMMA-based devices generated average 135 mV which was higher than average 100 mV generation of PEDOT:PSS-based devices; which indicated that the PMMA-based devices had slower screening rate. On the contrary, the PMMA-based devices’ 7 times higher series resistance than PEDOT:PSS-based devices caused the PL of PMMA-based devices to be 0.4 μW cm-2, which was two orders of magnitude lower than 54 μW cm-2 generated by PEDOT:PSS-based devices. Further to electrode materials study, polarisation screening caused by electrical properties of ZnO was also anaylsed. In this regard, the surface-induced conductivity of ZnO was decreased by using surface coating of copper thiocyanate (CuSCN). The reduction in ZnO conductivity was considered to reduce the screening of polarisation charges. Consequently, the power density of ZnO devices was enhanced from 54 μW cm-2 to 434 μW cm-2.
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Lechuga, Aranda Jesus Javier. "Interfaces In Hydraulic Pressure Energy Harvesters." Licentiate thesis, Mittuniversitetet, Institutionen för elektronikkonstruktion, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-36106.

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The fourth industrial revolution is here and with it a tidal wave of challenges for its prosperous implementation. One of the greatest challenges frustrating the development of the internet of things, and hence the next industrial revolution, is the powering of wireless sensors, as these depend on batteries with a limited lifetime. Recent advances have shown that energy harvesting technologies can be employed to extend the lifetime of batteries and ultimately replace them, thus facilitating the deployment of autonomous self-powered sensors, key components of the internet of things. Energy harvesting is the process of capturing ambient energy and convertingit into electric power. For energy harvesting devices it is crucial that the transduction of energy is as efficient as possible, meaning that the methods for capturing, interfacing and converting the ambient energy should be understood and characterized for every application. This thesis investigates the harvesting of the energy found in pressure fluctuations in hydraulic systems, a widely used power transmission system used in the industry and consumer applications; the focus is on the fluid interface and energy focusing methods. In summary, the contributions in this thesis show that the methods for converting pressure fluctuations in hydraulic systems to electrical power depend on the hydraulic system environment, in essence, the static pressure and the frequency of the pressure fluctuations. The results can serve as a starting point in the research, design, and development of hydraulic pressure energy harvesters.
Den fjärde industriella revolutionen är här vilket innebär en rad utmaningar för att dess utveckling ska bli framgångsrik. En av de största utmaningarna som begränsar utvecklingen av sakernas internet för industriella tillämpningar är strömförsörjningen av trådlösa sensorer då dessa är beroende av batterier med begränsad livslängd. Nya framsteg har emellertid gjorts med tekniker för energiskördning som gör att livslängden för batterierna kan förlängas ochi förlängningen helt ersätta batterierna. Det, i sin tur, möjliggör autonoma sensorer som är självförsörjande på energi som är viktiga komponenter i sakernas internet. Energiskördning är den process som omvandlar energi som finns i omgivningen till elektrisk energi. För att kunna få ut så mycket energi som möjligt så är det avgörande att energiskördarna gör energiomvandlingen så effektivt som möjligt. Det gör att inhämtning av omgivande energi samt gränssnitt och energiomvandling måste förstås och karakteriseras för varje tillämpning. Den här avhandlingen undersöker energiskördning för hydrauliskasystem där tryckfluktuationer i dessa system är energikällan. Syftet med den här studien är att ta fram metoder för uppskattning och karakterisering av de nödvändiga gränssnitten för inhämtning, fokusering, och omvandling av fluktuationer i hydraultryck till elektrisk energi. Sammanfattningsvis visar avhandlingen att metoder för att omvandla tryckfluktuationer i hydraulsystem till elektrisk energi beror på den hydrauliska systemmiljön där det statiska trycket och frekvensen av tryckfluktuationerna är de viktigaste parametrarna. Resultaten kan fungera som utgångspunkt för fortsatt forskning och utveckling av energiskördare för hydrauliska system.
SMART (Smarta system och tjänster för ett effektivt och innovativt samhälle)
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Erturk, Alper. "Electromechanical Modeling of Piezoelectric Energy Harvesters." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/29927.

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Vibration-based energy harvesting has been investigated by several researchers over the last decade. The ultimate goal in this research field is to power small electronic components (such as wireless sensors) by using the vibration energy available in their environment. Among the basic transduction mechanisms that can be used for vibration-to-electricity conversion, piezoelectric transduction has received the most attention in the literature. Piezoelectric materials are preferred in energy harvesting due to their large power densities and ease of application. Typically, piezoelectric energy harvesters are cantilevered structures with piezoceramic layers that generate alternating voltage output due to base excitation. This work presents distributed-parameter electromechanical models that can accurately predict the coupled dynamics of piezoelectric energy harvesters. First the issues in the existing models are addressed and the lumped-parameter electromechanical formulation is corrected by introducing a dimensionless correction factor derived from the electromechanically uncoupled distributed-parameter solution. Then the electromechanically coupled closed-form analytical solution is obtained based on the thin-beam theory since piezoelectric energy harvesters are typically thin structures. The multi-mode electromechanical frequency response expressions obtained from the analytical solution are reduced to single-mode expressions for modal vibrations. The analytical solutions for the electromechanically coupled voltage response and vibration response are validated experimentally for various cases. The single-mode analytical equations are then used for deriving closed-form relations for parameter identification and optimization. Asymptotic analyses of the electromechanical frequency response functions are given along with expressions for the short-circuit and the open-circuit resonance frequencies. A simple experimental technique is presented to identify the optimum load resistance using only a single resistor and an open-circuit voltage measurement. A case study is given to compare the power generation performances of commonly used monolithic piezoceramics and novel single crystals with a focus on the effects of plane-stress material constants and mechanical damping. The effects of strain nodes and electrode configuration on piezoelectric energy harvesting are discussed theoretically and demonstrated experimentally. An approximate electromechanical solution using the assumed-modes method is presented and it can be used for modeling of asymmetric and moderately thick energy harvester configurations. Finally, a piezo-magneto-elastic energy harvester is introduced as a non-conventional broadband energy harvester.
Ph. D.
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Hehn, Thorsten [Verfasser], and Yiannos [Akademischer Betreuer] Manoli. "A CMOS Integrated Interface Circuit for Piezoelectric Energy Harvesters = Eine CMOS-Integrierte Schnittstellenschaltung für Piezoelektrische Energy Harvester." Freiburg : Universität, 2014. http://d-nb.info/1123479119/34.

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Tran, Thang Quang. "DYNAMIC RESPONSE OF AND POWER HARVESTED BY ROTATING PIEZOELECTRIC VIBRATION ENERGY HARVESTERS THAT EXPERIENCE GYROSCOPIC EFFECTS." OpenSIUC, 2017. https://opensiuc.lib.siu.edu/theses/2157.

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This study investigates energy harvesting characteristics from a spinning device that consists of a proof mass that is supported by two orthogonal elastic structures with the piezoelectric material. Deformation in the piezoelectric structures due to vibration of the proof mass generates voltages to power electrical loads. The governing equations for this electromechanically coupled device are derived using Newtonian mechanics and Kirchhoff's voltage law. The case where the device rotates at a constant speed and is subjected to sinusoidal base excitation is examined in detail. The energy harvesting behavior is investigated for devices with identical piezoelectric support structures (called tuned devices). Closed-form expressions are derived for the steady state response and power harvested. For nonzero rotation speeds, these devices have multifrequency dynamic response and power harvested due to the combined vibration and rotation of the host system. The average power harvested for one oscillation cycle is calculated for a wide range of operating conditions to quantify the devices' performance. Resonances do not occur for cases when the base excitation frequency is fixed and the rotation speed varies. For cases of fixed rotation speed and varying base excitation frequency, however, resonances do occur. The number and location of these resonances depend on the electrical circuit resistances and rotation speed. Resonances do not occur at speeds or frequencies predicted by resonance diagrams, which are commonly used in the study of rotating system vibration. These devices have broadband speed energy harvesting ability. They perform equally well at high and low speeds; high speeds are not necessary for their optimal performance. The impact of the chosen damping model on energy harvesting characteristics for tuned devices is investigated. Two common damping models are considered: viscous damping and structural (hysteretic) damping. Closed-form expressions for steady state dynamic response and power harvested are derived for models with viscous and structural damping. The average power harvested using the model with structural damping behaves similarly at high speeds and low speeds, and at high resistances and low resistances. For the viscous damping model, however, the average power harvested is meaningfully different at high speeds compared to low speeds, and at high resistances compared to low resistances. The characteristics of devices with nonidentical piezoelectric support structures (called mistuned devices) are investigated numerically. Similar to spinning tuned devices, mistuned devices have multifrequency dynamic response and power harvested. In contrast to tuned devices, high amplitude average power harvested occurs near speeds and base excitation frequencies predicted by resonance diagram.
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Li, Xuan. "Design and development of hybrid energy harvesters." Thesis, Queen Mary, University of London, 2018. http://qmro.qmul.ac.uk/xmlui/handle/123456789/42507.

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Hybrid energy harvesters (HEHs) targeting multiple energy forms have been drawing increasing interest in recent years. While large scale photovoltaic power plants are capable of providing energy for domestic usage, research has also been focused on kinetic energy harvester with less power output which can be integrated into self-powered electronics such as implantable device, remote wireless sensor, wearables, etc. A number of successful designs of hybrid energy harvesters have been demonstrated which could scavenge solar and kinetic energy simultaneously. However the structures remain complicated; the majority of the designs involve different types of energy harvesters connected in series, which involves complex fabrication processes. Here, a simple structure based on a p-n junction piezoelectric nanogenerator (NG) was designed. The utilization of columnar piezoelectric n-type ZnO nanorods coated with light absorber layer enabled the device to harvest both kinetic and solar energy. This was adapted to either form a N719-based dye-sensitized solar cell (N719-HEH), or a perovskite solar cell (PSC-HEH). To allow high processing temperatures while maintaining mechanical flexibility, Corning© Willow™ (CW) glass substrate was used and compared to the more common ITO/PET. CW showed 56% lower charge transfer resistance and a related 4 times fold increase in power conversion efficiency for N719-HEHs. Oscillation (NG effect) and illumination (PV effect) testing indicated that both N719-HEHS and PSC-HEHs operated as kinetic and solar energy harvesters separately, with the current generated by the photovoltaic orders of magnitude greater than it from mechanical excitation. In addition, under illumination, both N719-HEHs and PSC-HEHs demonstrated further current output enhancement when oscillation was applied. The fact that the current output under NG+PV condition was higher than the summation of current output achieved under NG and PV conditions individually, suggests the piezoelectric potential originated from ZnO affected the charge dynamics within the devices. Thus, HEHs with enhanced output were successfully designed and developed.
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Li, Yuan. "Investigation into new non-linear energy harvesters." Thesis, University of Southampton, 2015. https://eprints.soton.ac.uk/388049/.

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Energy harvesting from ambient vibration has arose ever-increasing research interests in recent decades. Using non-linear mechanism for vibration energy harvesting has shown considerable effectiveness due to its capability of generating non-linear responses without the requirement of additional external tuning techniques thus it can harvest energy over broader band of frequencies. In this thesis, a non-linear Smooth and Discontinuous (SD) oscillator is investigated as a new type of SD nonlinear energy harvester to explore the potential of energy harvesting and develop an effective energy harvesting system. The findings of this research are examined to enhance the performance of the energy harvesting efficiency. The nonlinear dynamical properties of SD oscillator are firstly studied. The study shows that the oscillation can be local or global depending on the level of input power and geometric parameters, due to the double well potential mechanism. A harmonic external base excitation is then introduced to investigate the dynamic response and power flow behaviour of a single degree-of-freedom (DOF) SD oscillation system. Both analytical and numerical methods are applied. It has been shown that the existence of bifurcation is sensitive to the nonlinearity and excitation level. The single DOF SD energy harvester is developed by attaching electromagnetic induction system to convert kinetic energy into electrical energy. Moreover, power flow variables, especially the consumed energy by electrical resistor, are calculated to examine the effects of damping and electromechanical coupling coefficients. It is seen that the system is sensitive to both the parameters. The response can be chaotic, periodic or quasi-periodic with a small change of these two values. With the full use of analysis results of the studied single DOF SD system, a two-DOF SD oscillation system is then established. The mass and frequency ratios indicate energy exchange between the two masses. An integrated two-DOF SD vibrational energy harvester is then developed, coupling with the electrical energy extraction system. Parameters in the electrical conversion system are also investigated. It is found that the electrical coupling coefficients have significant influence on power transmission from mechanical to electrical system. Numerical simulation is performed to validate the energy generation efficiency by changing significant system parameters. It shows 50 watts of generated power for the SD energy harvester under harmonic excitation. The results demonstrate improved benefits particularly in terms of broadband vibrational energy harvesting, especially in the frequency region below the resonance frequency, under harmonic external base excitation. In addition, random excitations of both Gaussian white noise and random ocean wave, e.g. JONSWAP wave spectrum to the SD system are studied in detail. The investigations on dynamic behaviours and power flow properties indicate the considerable advantages of SD system in terms of broad band vibrational energy harvesting. The research provides a new insight into the SD vibrational energy harvesting method from both harmonic and stochastic ambient vibrations points of view. The new knowledge base through this study and explored advantages of the new type of nonlinear SD energy harvesting from ambient vibrations lays the theoretical foundation for the future design of SD energy harvester for applications in engineering.
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Books on the topic "Harvesters"

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Harvesters. New York: PowerKids Press, 2012.

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Franck, Irene M. Harvesters. New York: Facts on File Publications, 1987.

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Dugga, Victor Samson. Hope harvesters. Lagos State, Nigeria: DAT & Partners, 2008.

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Combines & harvesters. Osceola, WI, USA: Motorbooks International, 1994.

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Creighton, Jeff. Combines & harvesters. Osceola, WI, USA: Motorbook International, 1996.

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Briscoe, Joe, and Steve Dunn. Nanostructured Piezoelectric Energy Harvesters. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-09632-2.

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Wilkie, Jim. An illustrated history of combine harvesters. Hersham: Ian Allan, 2001.

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Wilkie, Jim. An illustrated history of combine harvesters. Hersham: Ian Allan, 2001.

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Hehn, Thorsten, and Yiannos Manoli. CMOS Circuits for Piezoelectric Energy Harvesters. Dordrecht: Springer Netherlands, 2015. http://dx.doi.org/10.1007/978-94-017-9288-2.

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Tortillas and tomatoes: Transmigrant Mexican harvesters in Canada. Montreal: McGill-Queen's University Press, 2002.

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Book chapters on the topic "Harvesters"

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Capinera, John L., Thomas O. Crist, John B. Heppner, Minos E. Tzanakakis, Severiano F. Gayubo, Aurélien Tartar, Pauline O. Lawrence, et al. "Harvesters." In Encyclopedia of Entomology, 1771. Dordrecht: Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-6359-6_1268.

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Park, Jae Yeong. "Piezoelectric MEMS Energy Harvesters." In Micro Energy Harvesting, 201–22. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2015. http://dx.doi.org/10.1002/9783527672943.ch10.

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Horowitz, Stephen, and Mark Sheplak. "Micromachined Acoustic Energy Harvesters." In Micro Energy Harvesting, 271–95. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2015. http://dx.doi.org/10.1002/9783527672943.ch13.

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Suzuki, Yuji. "Electrostatic/Electret-Based Harvesters." In Micro Energy Harvesting, 149–74. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2015. http://dx.doi.org/10.1002/9783527672943.ch8.

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Deng, Licheng, Zhiyu Wen, and Xingqiang Zhao. "MEMS Piezoelectric Vibration Energy Harvesters." In Toxinology, 1–37. Dordrecht: Springer Netherlands, 2017. http://dx.doi.org/10.1007/978-981-10-2798-7_40-1.

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Adhikari, Sondipon, and Michael I. Friswell. "Random Excitation of Bistable Harvesters." In Advances in Energy Harvesting Methods, 191–218. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-5705-3_8.

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Bendame, Mohamed, Eihab Abdel-Rahman, and Mostafa Soliman. "Electromagnetic Impact Vibration Energy Harvesters." In Springer Proceedings in Physics, 29–58. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-19851-4_2.

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Deng, Licheng, Zhiyu Wen, and Xingqiang Zhao. "MEMS Piezoelectric Vibration Energy Harvesters." In Micro/Nano Technologies, 1297–333. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-10-5945-2_40.

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ZWEIG, GUNTER, RU-YU GAO, JAMES M. WITT, WILLIAM J. POPENDORF, and K. T. BOGEN. "Exposure of Strawberry Harvesters to Carbaryl." In ACS Symposium Series, 123–38. Washington, D.C.: American Chemical Society, 1985. http://dx.doi.org/10.1021/bk-1985-0273.ch009.

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Tzou, Hornsen. "Linear/Nonlinear Piezoelectric Shell Energy Harvesters." In Piezoelectric Shells, 357–84. Dordrecht: Springer Netherlands, 2018. http://dx.doi.org/10.1007/978-94-024-1258-1_11.

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Conference papers on the topic "Harvesters"

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Doria, Alberto. "Framed Harvesters for Collecting Energy From Vibrations in Industrial Plants." In ASME 2019 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/detc2019-97291.

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Abstract The idea of increasing the number of resonance conditions of a cantilever piezoelectric harvester by coupling the harvester with a frame that surrounds the harvester’s body is presented and discussed. Experimental tests on prototypes show that it is possible to design framed harvesters able to generate significant powers at two frequencies. Since the framed harvesters will be used for harvesting energy from periodic vibrations characterized by multiple harmonics, a tuning method is needed. For this reason a numerical sensitivity analysis is performed to analyze the effect on harvester tuning of small masses mounted on the frame. A prototype tuned to 40 and 80 Hz is developed and tested, its performance is compared with the one of a system of two simple harvesters tuned to the same frequencies.
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Bibo, Amin, and Mohammed F. Daqaq. "New Insights Into the Performance and Optimization of Galloping Flow Energy Harvesters." In ASME 2014 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/smasis2014-7453.

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This paper presents a generalized formulation, analysis, and optimization of energy harvesters subjected to galloping and base excitations. The harvester consists of a cantilever beam with a bluff body attached at the free end. A nondimensional lumped-parameter model which accounts for the combined loading and different electro-mechanical transduction mechanisms is presented. The aerodynamic loading is modeled using the quasi-steady assumption with polynomial approximation. A nonlinear analysis is carried out and an approximate analytical solution is obtained. A dimensional analysis is performed to identify the important parameters that affect the system’s response. It is shown that the response curves of the harvester can be generated in terms of only three dimensionless loading parameters. These curves can serve as a complete design guide for scaling and optimizing the performance of galloping-based harvesters. As a special case study, a harvester subjected to only galloping excitations is analyzed. It is shown that, for a given shape of the bluff body and under quasi-steady flow conditions, the harvester’s dimensionless response can be described by a single universal curve irrespective to the geometric, mechanical, and electrical design parameters of the harvester. The universal curve is utilized to obtain the optimal harvesting circuit design parameters, that minimize the cut-in wind speed and maximize the output power, and predict the harvester’s total conversion efficiency.
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MAŠEK, Jiří, Petr NOVÁK, Milan KROULÍK, and Algirdas JASINSKAS. "PERFORMANCE EVALUATION OF COMBINE HARVESTERS." In Rural Development 2015. Aleksandras Stulginskis University, 2015. http://dx.doi.org/10.15544/rd.2015.014.

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The aim of this paper is a comparison of the operating parameters of combine harvesters in a selected farm. The working parameters were measured and evaluated on combine harvesters of the New Holland brand by different concepts of threshing. Field evaluation trials of combine harvester were carried out on private farm field in Central Bohemia region during the season of 2013 and 2014. Working parameters in this case mean the performance and economic indicators of the operation. Performance of the machines was measured per hectare, number of harvested hectares per day, respectively per hour or season. Fuel consumption was measured in litres and converted per hectare. Costs are calculated as fixed and variable and then summarized as total cost for a given machine. Experiments show differences in performance parameters of various threshing system of combine harvester. Tangential concept of NH CS660 had on average hourly performance of 3.1 ha h-1 the axial concept of NH CR960 had an average hourly performance of 4.6 ha h-1. Specific fuel consumption by the same throughput rate (6.5 kg s-1) is higher by using axial system (1.9 l t-1) than by tangential system (1.2 l t-1).
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Pedchenko, Alexander V., and Eric J. Barth. "Broad Frequency Vibration Energy Harvesting Control Approach Based on the Maximum Power Transfer Theorem." In ASME 2013 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/dscc2013-3981.

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A control law for an electromagnetic vibration energy harvester is derived using the maximum power transfer theorem. Using regenerative electronics, the controller cancels the reactive portion of the harvester’s impedance by eliminating the effect of mechanical inertia and stiffness elements, and the coil’s electrical inductive element. The result is an energy harvester approach that captures more vibrational energy than a passive tuned harvester. It is shown that the controlled system acts like an infinite series of passive harvesters tuned to all frequency components within a certain frequency range. The control approach also avoids the delay and computational overhead of a Fast Fourier Transform as it does not require the explicit calculation of the excitation frequency. An experimental prototype harvester was built and characterized. The prototype’s multi-domain dynamics were modeled using bond-graph techniques, and its behavior as a passive harvester was experimentally validated. The prototype’s behavior under the proposed control method is simulated and compared to the passive case. It is shown that the proposed control method harvests more power for a range of excitation frequencies than the passive harvester.
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Masana, Ravindra, and Mohammed F. Daqaq. "Comparing the Performance of a Nonlinear Energy Harvester in Mono- and Bi-Stable Potentials." In ASME 2011 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/detc2011-47828.

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The quest to develop broadband vibratory energy harvesters (VEHs) has recently motivated researchers to explore introducing nonlinearities into the harvester’s design. Some research efforts have demonstrated that this new class of nonlinear harvesters can outperform their traditional linear (resonant) counterparts; some others however concluded that nonlinearities can diminish the harvester’s transduction. Through this effort, we compare the performance of a nonlinear VEH operating in mono- and bi-stable potentials. With that objective, we consider an axially-loaded clamped-clamped piezoelectric beam which functions as an energy harvester in the mono-stable (pre-buckling) and bistable (post-buckling) configurations. For the purpose of fair performance comparison, the oscillation frequency around the stable equilibria of the harvester is tuned to equal values in both configurations. The harvester is then subjected to harmonic base excitations of different magnitudes and a slowly-varying frequency which spans a wide range around the tuned oscillation frequency. The output voltage measured across an arbitrarily chosen electric load is used as a relative performance measure. Both numerical and experimental results demonstrate that the shape of the potential function plays an essential role in conjunction with the magnitude of the base excitation to determine whether the bi-stable harvester can outperform the mono-stable one and for what range of frequencies.
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Alhadidi, Ali H., Amin Bibo, and Mohammed F. Daqaq. "Flow Energy Harvesters With a Nonlinear Restoring Force." In ASME 2014 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/smasis2014-7445.

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This ppppaper examines the performance of a galloping energy harvester possessing a nonlinear restoring force. To achieve this goal, a flow energy harvester consisting of a piezoelectric cantilever beam augmented with a square-sectioned bluff body at the free end is considered. Two magnets located near the tip of the bluff body are used to introduce the nonlinearity which strength and nature can be altered by changing the distance between the magnets. A lumped-parameter aero-electromechanical model adopting the quasi-steady assumption for aerodynamic loading is presented and utilized to numerically simulate the harvester’s response. Wind tunnel tests are also performed to validate the numerical simulations by conducting upward and downward wind velocity sweeps. Results comparing the relative performance of several harvesters with potential functions of different shapes demonstrate that a mono-stable potential function with a hardening restoring force can outperform all other configurations.
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Doria, Alberto, Cristian Medè, Daniele Desideri, Alvise Maschio, and Federico Moro. "Improvement of Harvesters for Tires by Means of Multi-Physics Simulation." In ASME 2017 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/detc2017-67301.

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The specific working conditions of piezoelectric harvesters for scooter tires are analyzed. Calculated and experimental results show that the excitation of the harvester can be considered a series of separated impulses. Harvester response to an ideal impulse is analyzed with a single-mode model. An optimal ratio between impulse duration and natural period of the harvester that maximizes harvester excitation is found. A numerical finite element (FE) model of a bimorph cantilever harvester is developed in COMSOL and validated by means of experimental tests. The validated FE model is used for showing that an actual harvester excited by road impulses generates a large voltage only if there is a specific relation between impulse duration and natural period of the harvester. Starting from the validated FE model, small harvesters suited to tires are developed and analyzed. Also these harvesters show the best performance for a specific range of impulse durations, which corresponds to the highest speeds of the speed range of the scooter (50–80 km/h) and to high levels of acceleration.
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Panyam, Meghashyam, and Mohammed F. Daqaq. "Characterizing the Effective Bandwidth of Tri-Stable Energy Harvesters." In ASME 2016 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/detc2016-59929.

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This paper aims to investigate the response and characterize the effective frequency bandwidth of tri-stable vibratory energy harvesters. To achieve this goal, the method of multiple scales is utilized to construct analytical solutions describing the amplitude and stability of the intra- and inter-well dynamics of the harvester. Using these solutions, critical bifurcations in the parameter’s space are identified and used to define an effective frequency bandwidth of the harvester. A piezoelectric tri-stable energy harvester consisting of a uni-morph cantilever beam is considered. Stiffness nonlinearities are introduced into the harvesters design by applying a static magnetic field near the tip of the beam. Experimental studies performed on the harvester are presented to validate some of the theoretical findings.
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Harne, R. L., and K. W. Wang. "An Axially-Suspended Vibration Energy Harvesting Beam for Broadband Performance and High Versatility." In ASME 2014 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/smasis2014-7417.

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It has recently been shown that negligible linear stiffness or very small negative stiffness may be the most beneficial stiffness nonlinearities for vibrational energy harvesters due to the broadband, amplified responses which result from such designs. These stiffness characteristics are often achieved by providing axial compression along the length of a harvester beam. Axial compressive forces induced using magnetic or electrostatic effects are often easily tuned; however, electrostatic energy harvesters are practically limited to microscale realizations and magnets are not amenable in a variety of applications, e.g. self-powered biomedical implants or when the harvesters are packaged with particular circuits. On the other hand, mechanically-induced pre-compression methods considered to date are less able to achieve fine control of the applied force which is typically governed by a pre-compression distance that has practical constraints such as resolution and tolerance. This notably limits the harvester’s ability to precisely obtain the desired near-zero or small negative linear stiffness and thus inhibits the favorable dynamical phenomena that lead to high energy conversion performance. Inspired by the wing motor structure of the common diptera (fly), this research explores an alternative energy harvester design and configuration that considerably improves control over pre-compression factors and their influence upon performance-improving dynamics. A pre-compressed harvester beam having an axial suspension on an end is investigated through theoretical and numerical studies and experimental efforts. Suspension and pre-loading adjustments are found to enable comprehensive variation over the resulting dynamics. It is shown that the incorporation of adjustable axial suspension into the design of pre-compressed energy harvester beams is therefore a versatile, all-mechanical means to enhance the performance of such devices and ensure favorable dynamics are retained across a wide range of excitation conditions.
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Masana, Ravindra, and Mohammed F. Daqaq. "Performance of a Randomly-Excited Nonlinear Energy Harvester in Mono- and Bi-Stable Potentials: An Experimental Investigation." In ASME 2012 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/detc2012-71451.

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This paper aims to experimentally investigate the influence of stiffness-type nonlinearities on the transduction of vibratory energy harvesters (VEHs) under random white and colored excitations. For the purpose of the study, an energy harvester consisting of a clamped-clamped piezoelectric beam bi-morph is considered. The shape of the harvester’s potential function is altered by applying a static compressive axial load at one end of the beam. The axial load permits the harvester to operate with different potential energy characteristics; namely, the mono-stable (pre-buckling) and bi-stable (post-buckling) configurations. The performance of the harvester in both configurations is investigated and compared by tuning the harvester’s oscillation frequencies around the static equilibria such that they have equal values in both scenarios. The harvester is then subjected to random base excitations of different levels, bandwidths, and center frequencies. The variance of the output voltage is measured across an arbitrary, purely resistive load and used for the purpose of performance comparison. Critical conclusions pertinent to the influence of the nonlinearity and relative performance in both configurations are presented and discussed.
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Reports on the topic "Harvesters"

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Bachand, Marlene, George David Bachand, Adrienne Celeste Greene, and Amanda Carroll-Portillo. In vivo collection of rare proteins using kinesin-based "nano-harvesters". Office of Scientific and Technical Information (OSTI), November 2008. http://dx.doi.org/10.2172/945902.

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McLain, Rebecca J., Erika Mark McFarlane, and Susan J. Alexander. Commercial morel harvesters and buyers in western Montana: an exploratory study of the 2001 harvesting season. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station, 2005. http://dx.doi.org/10.2737/pnw-gtr-643.

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Skone, Timothy J. Tree Harvester, 241 HP, Construction. Office of Scientific and Technical Information (OSTI), May 2012. http://dx.doi.org/10.2172/1509212.

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Skone, Timothy J. Diesel Forage Harvester, 615 Horsepower, Construction. Office of Scientific and Technical Information (OSTI), January 2010. http://dx.doi.org/10.2172/1509044.

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Skone, Timothy J. Tree Harvester Chipper, 440 Horsepower, Construction. Office of Scientific and Technical Information (OSTI), January 2010. http://dx.doi.org/10.2172/1509211.

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Prasad, Nadipuram R., and Satishkuma J. Ranade. Final Report of the HyPER Harvester Project. Office of Scientific and Technical Information (OSTI), November 2015. http://dx.doi.org/10.2172/1306335.

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Skone, Timothy J. Harvester, 300-Bushel Capacity, 6 Cylinder, Construction. Office of Scientific and Technical Information (OSTI), December 2009. http://dx.doi.org/10.2172/1509069.

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Below, M., C. Michel, M. Kearney, and C. Milloy. Ottawa harvested hydrogeological information geodatabase. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2017. http://dx.doi.org/10.4095/299757.

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Brackley, Allen M., Richard W. Haynes, and Susan J. Alexander. Timber harvests in Alaska: 1910-2006. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station, 2009. http://dx.doi.org/10.2737/pnw-rn-560.

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Knapp, G. Native timber harvests in southeast Alaska. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station, 1992. http://dx.doi.org/10.2737/pnw-gtr-284.

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