The Effect of Varying Environmental Conditions on the Performance of Triboelectric Generators

As data creation and collection continues to increase globally, the number of sensors needed to gather data also grows. One thing all types of sensors have in common is their need for power; however, current power sources, like batteries, are limited by their life, size, and weight. To reduce these power limitations, triboelectric energy generators (TENGs) can be used to generate power from the mechanical motion that is present throughout packaged product transport. Triboelectric generation is one such low power mechanism that due to its low cost, has potential in packaging applications. In the distribution environment, packaged products are exposed to a wide range of temperatures and relative humidities. It is important to know how the relative humidities and temperatures seen in packaging distribution environments affect the voltage output of triboelectric energy generators. In order to study relative humidity and temperature effect on TENGs, we mount an optimized triboelectric generator to an electrodynamic shaker located inside an environmental chamber and measure voltage output. This set up allows us to replicate sinusoidal vibration inputs over a wide range of environmental conditions. We found that as relative humidity increases, TENG’s root mean square (RMS) voltage output remains essentially the same, and as temperature increases, the TENG’s RMS voltage output also remains basically same. We also determined that charge build up is not affected by relative humidity and temperatures found within the packaging distribution environment and that steady state takes longer to establish than a few hundred seconds

Vibration energy harvesting using the Halbach array

This paper studies the feasibility of vibration energy harvesting using a Halbach array. A Halbach array is a specific arrangement of permanent magnets that concentrates the magnetic field on one side of the array while cancelling the field to almost zero on the other side. This arrangement can improve electromagnetic coupling in a limited space. The Halbach array offers an advantage over conventional layouts of magnets in terms of its concentrated magnetic field and low-profile structure, which helps improve the output power of electromagnetic energy harvesters while minimizing their size. Another benefit of the Halbach array is that due to the existence of an almost-zero magnetic field zone, electronic components can be placed close to the energy harvester without any chance of interference, which can potentially reduce the overall size of a self-powered device. The first reported example of a low-profile, planar electromagnetic vibration energy harvester utilizing a Halbach array was built and tested. Results were compared to ones for energy harvesters with conventional magnet layouts. By comparison, it is concluded that although energy harvesters with a Halbach array can have higher magnetic field density, a higher output power requires careful design in order to achieve the maximum magnetic flux gradient

Review of flexible energy harvesting for bioengineering in alignment with SDG

To cater to the extensive body movements and deformations necessitated by biomedical equipment flexible piezoelectrics emerge as a promising solution for energy harvesting. This review research delves into the potential of Flexible Piezoelectric Materials (FPM) as a sustainable solution for clean and affordable energy, aligning with the United Nations' Sustainable Development Goals (SDGs). By systematically examining the secondary functions of stretchability, hybrid energy harvesting, and self-healing, the study aims to comprehensively understand these materials' mechanisms, strategies, and relationships between structural characteristics and properties. The research highlights the significance of designing piezoelectric materials that can conform to the curvilinear shape of the human body, enabling sustainable and efficient mechanical energy capture for various applications, such as biosensors and actuators. The study identifies critical areas for future investigation, including the commercialization of stretchable piezoelectric systems, prevention of unintended interference in hybrid energy harvesters, development of consistent wearability metrics, and enhancement of the elastic piezoelectric material, electrode circuit, and substrate for improved stretchability and comfort. In conclusion, this review research offers valuable insights into developing and implementing FPM as a promising and innovative approach to harnessing clean, affordable energy in line with the SDGs.</p

Review of flexible energy harvesting for bioengineering in alignment with SDG

To cater to the extensive body movements and deformations necessitated by biomedical equipment flexible piezoelectrics emerge as a promising solution for energy harvesting. This review research delves into the potential of Flexible Piezoelectric Materials (FPM) as a sustainable solution for clean and affordable energy, aligning with the United Nations' Sustainable Development Goals (SDGs). By systematically examining the secondary functions of stretchability, hybrid energy harvesting, and self-healing, the study aims to comprehensively understand these materials' mechanisms, strategies, and relationships between structural characteristics and properties. The research highlights the significance of designing piezoelectric materials that can conform to the curvilinear shape of the human body, enabling sustainable and efficient mechanical energy capture for various applications, such as biosensors and actuators. The study identifies critical areas for future investigation, including the commercialization of stretchable piezoelectric systems, prevention of unintended interference in hybrid energy harvesters, development of consistent wearability metrics, and enhancement of the elastic piezoelectric material, electrode circuit, and substrate for improved stretchability and comfort. In conclusion, this review research offers valuable insights into developing and implementing FPM as a promising and innovative approach to harnessing clean, affordable energy in line with the SDGs.</p

An investigation on energy harvesting from wrist for smart electronic devices

In this thesis energy harvested using the wrist movement of human arm is discussed. Human arm is constantly being used during our normal routine work, walking running or doing chores. These actions could be helpful in producing electricity. Previously research has been performed on the human body's ability to produce energy. Magnets have been utilized to design a device that harvests the energy using the wrist movement for electronic devices. The magnets were placed inside a 3-D printed tube and coils were wrapped the tube to convert the electromagnetic field into electricity. It can be worn to collect energy all day long. To determine the maximum performance throughout the arm movements, simulations were performed on software called COMSOL. The experiments were carried out by placing this device on the shaker and open circuit voltage was calculated with and without a resistor using an oscilloscope. The open circuit voltage generated at the least frequency of the shaker was 0.24 V and 0.064 V with resistance and without resistance, respectively. Different frequencies were applied to further measure the voltages. As batteries are constantly being needed to be replaced for the wearable electronic devices so, we developed the device which will continuously recharge them. This is a significant step towards future wearable electronics not requiring battery maintenance as it can charge the batteries as the wearer is normally doing their work in their routine.Bu tezde insan kolunun bilek hareketi kullanılarak elde edilen enerji ele alınmıştır. Normal rutin işlerimizde, yürürken, koşarken veya ev işleri yaparken insan kolu sürekli olarak kullanılmaktadır. Bu eylemler elektrik üretiminde yardımcı olabilir. Daha önce insan vücudunun enerji üretme yeteneği üzerine araştırmalar yapılmıştır. Bu çalışmada mıknatıslar, elektronik cihazlar için bilek hareketini kullanarak enerji toplayan bir cihaz tasarlamak için kullanıldı. Mıknatıslar, 3 boyutlu baskılı bir tüpün içine yerleştirildi ve elektromanyetik alanı elektriğe dönüştürmek için tüpe bobinler sarıldı. Bu cihaz gün boyu enerji toplamak için giyilebilir. Kol hareketleri boyunca maksimum performansı belirlemek için COMSOL adı verilen yazılım üzerinde simülasyonlar yapılmıştır. Bu cihaz çalkalayıcı üzerine yerleştirilerek deneyler yapılmış ve osiloskop kullanılarak dirençli ve dirençsiz açık gerilim voltajı hesaplanmıştır. Çalkalayıcının en düşük frekansında üretilen açık devre voltajı dirençli ve dirençsiz durum için sırasıyla 0,24 V ve 0,064 V olmuştur. Voltajları daha fazla ölçmek için farklı frekanslar uygulandı. Giyilebilir elektronik cihazlar için pillerin sürekli olarak değiştirilmesi gerekmektedir. Bu, pilleri şarj edebildiği için pil bakımı gerektirmeyen, geleceğin giyilebilir elektronik cihazlarına doğru önemli bir adımdır çünkü kullanıcı normal olarak rutin işlerini yaparken pilleri şarj edebilir.No sponso

Applications of nanogenerators for biomedical engineering and healthcare systems

The dream of human beings for long living has stimulated the rapid development of biomedical and healthcare equipment. However, conventional biomedical and healthcare devices have shortcomings such as short service life, large equipment size, and high potential safety hazards. Indeed, the power supply for conventional implantable device remains predominantly batteries. The emerging nanogenerators, which harvest micro/nanomechanical energy and thermal energy from human beings and convert into electrical energy, provide an ideal solution for self‐powering of biomedical devices. The combination of nanogenerators and biomedicine has been accelerating the development of self‐powered biomedical equipment. This article first introduces the operating principle of nanogenerators and then reviews the progress of nanogenerators in biomedical applications, including power supply, smart sensing, and effective treatment. Besides, the microbial disinfection and biodegradation performances of nanogenerators have been updated. Next, the protection devices have been discussed such as face mask with air filtering function together with real‐time monitoring of human health from the respiration and heat emission. Besides, the nanogenerator devices have been categorized by the types of mechanical energy from human beings, such as the body movement, tissue and organ activities, energy from chemical reactions, and gravitational potential energy. Eventually, the challenges and future opportunities in the applications of nanogenerators are delivered in the conclusive remarks. The combination of nanogenerator and biomedicine have been accelerating the development of self‐powered biomedical devices, which show a bright future in biomedicine and healthcare such as smart sensing, and therapy

Parametric study of a triboelectric transducer in total knee replacement application

Triboelectric energy harvesting is a relatively new technology showing promise for biomedical applications. This study investigates a triboelectric energy transducer for potential applications in total knee replacement (TKR) both as an energy harvester and a sensor. The sensor can be used to monitor loads at the knee joint. The proposed transducer generates an electrical signal that is directly related to the periodic mechanical load from walking. The proportionality between the generated electrical signal and the load transferred to the knee enables triboelectric transducers to be used as self-powered active load sensors. We analyzed the performance of a triboelectric transducer when subjected to simulated gait loading on a joint motion simulator. Two different designs were evaluated, one made of Titanium on Aluminum, (Ti-PDMS-Al), and the other made of Titanium on Titanium, (Ti-PDMS-Ti). The Ti-PDMS-Ti design generates more power than Ti-PDMS-Al and was used to optimize the structural parameters. Our analysis found these optimal parameters for the Ti-PDMS-Ti design: external resistance of 304 M Ω, a gap of 550 µm, and a thickness of the triboelectric layer of 50 µm. Those parameters were optimized by varying resistance, gap, and the thickness while measuring the power outputs. Using the optimized parameters, the transducer was tested under different axial loads to check the viability of the harvester to act as a self-powered load sensor to estimate the knee loads. The forces transmitted across the knee joint during activities of daily living can be directly measured and used for self-powering, which can lead to improving the total knee implant functions

A 3D printed electromagnetic nonlinear vibration energy harvester

A 3D printed electromagnetic vibration energy harvester is presented. The motion of the device is in-plane with the excitation vibrations, and this is enabled through the exploitation of a leaf isosceles trapezoidal flexural pivot topology. This topology is ideally suited for systems requiring restricted out-of-plane motion and benefits from being fabricated monolithically. This is achieved by 3D printing the topology with materials having a low flexural modulus. The presented system has a nonlinear softening spring response, as a result of designed magnetic force interactions. A discussion of fatigue performance is presented and it is suggested that whilst fabricating, the raster of the suspension element is printed perpendicular to the flexural direction and that the experienced stress is as low as possible during operation, to ensure longevity. A demonstrated power of ~25 μW at 0.1 g is achieved and 2.9 mW is demonstrated at 1 g. The corresponding bandwidths reach up-to 4.5 Hz. The system's corresponding power density of ~0.48 mW cm−3 and normalised power integral density of 11.9 kg m−3 (at 1 g) are comparable to other in-plane systems found in the literature

Available Technologies and Commercial Devices to Harvest Energy by Human Trampling in Smart Flooring Systems: a Review

Technological innovation has increased the global demand for electrical power and energy. Accordingly, energy harvesting has become a research area of primary interest for the scientific community and companies because it constitutes a sustainable way to collect energy from various sources. In particular, kinetic energy generated from human walking or vehicle movements on smart energy floors represents a promising research topic. This paper aims to analyze the state-of-art of smart energy harvesting floors to determine the best solution to feed a lighting system and charging columns. In particular, the fundamentals of the main harvesting mechanisms applicable in this field (i.e., piezoelectric, electromagnetic, triboelectric, and relative hybrids) are discussed. Moreover, an overview of scientific works related to energy harvesting floors is presented, focusing on the architectures of the developed tiles, the transduction mechanism, and the output performances. Finally, a survey of the commercial energy harvesting floors proposed by companies and startups is reported. From the carried-out analysis, we concluded that the piezoelectric transduction mechanism represents the optimal solution for designing smart energy floors, given their compactness, high efficiency, and absence of moving parts

A high-performance electromagnetic vibration energy harvester based on ring magnets with Halbach configuration

This paper proposes and studies a ring-shaped architecture with Halbach configuration for electromagnetic vibration energy harvesters. The proposed transducer consists of three ring magnets with a linear Halbach array that concentrates its magnetic field in the inner space of the mechanism where a single vertically-centered concentric coil has been located. This particular structure allows to increase the resonant mass within a fixed dimensions of the transducer and reduces the coil resistance for the same number of turns, enhancing its power generation capabilities. The ring-shaped architecture has been compared with several ring magnet arrangements, including single magnets, double-magnet arrays, and an alternative linear Halbach array, using numerical simulations to determine their influence on its performance. Consequently, this work is the first contribution to the applicability of Halbach configurations for electromagnetic vibration energy harvesters within ring-shaped architectures. Also, a geometrical optimization of the proposed transducer has been conducted, mainly as a function of the inner radius, the height, and the wire diameter of the coil, to increase its power generation. The maximum simulated output power for the optimized generator reaches 3.61 mW for an input harmonic vibration of 0.03 g at a frequency of 61.7 Hz, corresponding to a 29.08 mW/cm 3 g 2 normalized power density performance, significantly higher than devices described in the literature for similar applications. Besides, a harvester prototype based on the proposed configuration has been fabricated to validate the modeling strategy used and to certify the reliability of the proposed design regarding power generation capabilities. Several experimental tests have been conducted under harmonic excitation with frequencies ranging between 10 Hz and 100 Hz and a vibration amplitude of 0.03 g. The experimentally measured induced voltage and electrical output power have been found in good agreement with their corresponding simulated values, with a difference of about 2.1% and 5%, respectivelyPostprint (published version