Piezoelectric Energy Harvester for IoT Sensor Devices

Limited battery power is a major challenge for wireless sensor network (WSN) in internet of things (IoT) applications, especially in hard-to-reach places that require periodic battery replacement. The energy harvesting application is intended as an alternative to maintain network lifetime by utilizing environmental energy. The proposed method utilized piezoelectricity to convert vibration or pressure energy into electrical energy through a modular piezoelectric energy harvesting design used to supply energy to sensor nodes in WSN. The module design consisted of several piezoelectric elements, of which each had a different character in generating energy. A bridge diode was connected to each element to reduce the feedback effect of other elements when pressure was exerted. The energy produced by the piezoelectric is an impulse so that the capacitor was used to quickly store the energy. The proposed module produced 7.436 μJ for each step and 297.4 μJ of total energy with pressure of a 45 kg load 40 times with specific experiments installed under each step. The energy could supply WSN nodes in IoT application with a simple energy harvesting system. This paper presents a procedure for measuring the energy harvested from a commonly available piezoelectric buzzer. The specific configurations of the piezoelectric and the experiment setups will be explained. Therefore, the output energy characteristics will be understood. In the end, the potentially harvested energy can be estimated. Therefore, the configuration of IoT WSN could be planned.

LLC DC-DC Converter Performances Improvement for Bidirectional Electric Vehicle Charger Application

Electric Vehicle (EV) bidirectional charger technology is growing in importance. It defines the fact of returning the electricity stored in the batteries of EV to Grid (V2G), to Home (V2H), to Load (V2L), or in one word V2X mode. The EV onboard charger is divided into two parts: AC-DC and DC-DC converters. The isolated bidirectional DC-DC LLC resonant converter is used to improve the charger efficiency within both battery power and voltage ranges. It is controlled by varying the switching frequency based on a small signal modeling approach using the gain transfer function inversion method. The dimensions of the DC-DC LLC converter directly affect the charger cost. Moreover, they cause an important control frequency saturation zone, especially in V2X mode, where the switching frequency is out of the feasibility zone. The new challenge in this paper is to design an optimization strategy to minimize the LLC converter cost and improve the control frequency feasibility zone, for a wide variation of battery voltage and converter power, in the charging (G2V) and discharging (V2X) modes simultaneously. For our best knowledge, this optimization problem, in the case of a bidirectional (G2V and V2X) charger, is not yet considered in the literature. An optimal design that considers the control stability equations in the optimization algorithm is elaborated. The obtained results show a significant converter cost decrease and important expansion of control frequency feasibility zones. A comparative study between initial and optimized values, in G2V and V2X modes, is generated according to the converter efficiency.

Mechanical Durability Assessment of an Energy-Harvesting Piezoelectric Inverted Flag

This paper presents results from a practical assessment of the endurance of an inverted flag energy harvester, tested over multiple days in a wind tunnel to provide first insights into flapping fatigue and failure. The inverted flag is a composite bimorph, composed of PVDF (polyvinylidene difluoride) strips combined with a passive metallic core to provide sufficient stiffness. The flag, derived from an earlier, more extensive study, flaps with a typical amplitude of ~120 degrees and a frequency of ~2 Hz, generating a constant power of ~0.09 mW in a wind velocity of 6 m/s. The flag was observed to complete ~5×105 cycles before failure, corresponding to ~70 h of operation. The energy generated over this lifespan is estimated to be sufficient to power a standard low-power temperature sensor for several months at a sampling rate of one sample/minute, which would be adequate for applications such as wildfire detection, environmental monitoring, and agriculture management. This study indicates that structural fatigue may present a practical obstacle to the wider development of this technology, particularly in the context of their usual justification as a ‘deploy and forget’ alternative to battery power. Further work is required to improve the fatigue resistance of the flag material.

SECURING IOT WITH BLOCKCHAIN

IoT is becoming ubiquitous in industry, homes, cities, literally in every aspect of our daily lives. Securing IoT-based systems is difficult because of deficiencies in the very nature of IoT devices such as limited battery power, processing, and storage, etc. Blockchain is a new approach used to securely record transactions and offers potential solutions to computer and internet security issues such as confidentiality, integrity, availability, authentication, authorization, and accountability. Blockchain, as a decentralized ledger consisting of interconnected blocks, can remedy most of the security deficiencies of heavily IoT based systems. The Hyperledger Fabric blockchain network used in this study provides confidentiality, data integrity, authentication, and data security for data obtained from IoT devices. Widely used IoT data transfer MQTT protocol is included in the proposed approach. The approach is demonstrated in a simple demo Hyperledger network with simulated IoT devices. The proposed approach is discussed in terms of network security dimensions. Based on the features of the Hyperledger Blockchain network, it is displayed that the IoT security deficiencies can largely be remedied with the proposed approach.

Cost-Effective and Low Power IoT-Based Paper Supply Monitoring System: An Application Modeling Approach

IoT designers face the dual complexity of obtaining good application-level performance and user satisfaction under constraints on computing and power resources. We introduce a new IoT device for paper roll supply management in bathrooms and kitchens, both for homes and businesses, that is extremely cost effective and battery power-efficient. The device can be installed on practically any paper roll dispenser and makes use of existing Wi-Fi infrastructure. Despite Wi-Fi’s reputation as “unsupportive for power saving,” we introduce and experimentally validate a methodology for using Wi-Fi networks with low power utilization, resulting in a system that provides very good management of paper supplies while only requiring battery charging once every 3–4 months. The new device has the potential to provide more households and businesses with real-time, data-driven automated supply chains.

PERILAKU PENGGUNA ROKOK ELEKTRIK DAN DAMPAKNYA TERHADAP KEHIDUPAN SOSIAL, EKONOMI, DAN KESEHATAN PADA KOMUNITAS VAPERS PEKANBARU TAHUN 2020

Rokok Elektrik (vape) adalah rokok yang beroperasi menggunakan tenaga baterai. Namun tidak menggunakan teknik membakar seperti produk rokok biasa. Rokok ini memanaskan cairan atau liquid menggunakan perangkat elektronik batterai dan uap yang dihasilkan masuk ke paru-paru pemakai. Komunitas Vapers Pekanbaru diresmikan pada tahun 2017 yang mempunyai 50 orang anggota dan semua anggota menggkonsumsi rokok elektrik (vape). Penelitian ini dilakukan di cafe warkop pinggiran 45 Pekanbaru yang berlokasi dijalan Arifin Ahmad. Tujuan penelitian ini untuk mengetahui Perilaku Pengguna Rokok Elektrik (vape) dan Dampaknya Terhadap Kehidupan Sosial, Ekonomi, dan Kesehatan Pada Komunitas Vapers Pekanbaru Tahun 2020. Jenis Penelitian ini Kualitatif analitik yaitu dengan melakukan wawancara mendalam dan obeservasi. Subjek penelitian ini berjumlah 4 informan yaitu 3 informan utama dan 1 informan pendukung. Hasil penelitian ini masih rendahnya pengetahuan komunitas terhadap dampak rokok elektrik, perilaku komunitas rata-rata sebelumya pernah menggunakan rokok konvensional mengkonsumsi rokok elektrik setiap hari. Sikap komunitas bahwa rokok itu pilihan atau hak masing-masing. Dari kehidupan sosial komunitas merasa lebih percaya diri dalam mengkonsumsi rokok elektrik dan komunitas merasa sudah memiliki jiwa sosial kepada sesama. Sedangkan ekonomi komunitas vapers pekanbaru merasa lebih hemat mengkonsumsi rokok elektrik . Dan kesehatan komunitas merasa lebih baik setelah menggunakan rokok elektrik. E-cigarette (vape) is a cigarette that operates on battery power. However, it does not use burning techniques like cigarette products as usual. It heats the liquid using a battery electronic device and the result fumes enters the user's lungs. Pekanbaru Vapers Community was inaugurated in 2017 which has 50 members and all members consume e-cigarettes (vape). This research is conducted at WARKOP 45 Pekanbaru, which is located on Jalan Arifin Ahmad. The purpose of this research is to know the behavior of e-cigarette users (vape) and the impact on social, economic, and health life in the Pekanbaru Vapers Community in 2020. This research using qualitative analytic by conducted depth interview and observation. The subjects of this research are 4 informants, namely 3 main informants and 1 supporting informant. The result of this research is that community knowledge is still low on the impact of e-cigarettes, most of their behavior has ever used conventional cigarettes and also consume e-cigarettes every day, the community's attitude that smoking is their choice or right from social life, the community feels more confident in consuming e-cigarettes and the community feels that they have have a social soul to others. Meanwhile, the economy of the Pekanbaru vapers community feels that it is more economical to consume e-cigarettes and the community health feel better after using e-cigarettes. Suggestion to the Pekanbaru vapers community, it is recommended that they held frequent gathering with members to discuss further more the effectiveness of e-cigarettes so that they can help add information.

Eco-design of portable solar-powered telescopic lamp for off-grid areas in Indonesia

<p><span lang="EN-US">This study describes the development of eco-design of portable solar-powered telescopic lamp for off-grid area in Indonesia. Several design requirements for the lamp, namely, sustainability, portability, affordability, and reliability, are the objectives of the design process in this study. Sustainability is achieved through renewable energy and the application of eco-design principles. Portability means it is lightweight, compact and can be carried anywhere inside a tube. This solar-powered telescopic lamp was designed with a 3.7 V, 15.6 Ah battery power specification such that the battery power is around 57.72 Wh. The optimal use of the battery is 80% of the total battery power that is 46.176 Wh. With a power of 46,176 Wh, the battery can turn on the LED strip light with a 4.8 W power specification for 9.62 h. The test results showed that the telescopic lamp endurance met the expected specifications. The real consumed power by the LED strips was around 1.9 W. The charging test using solar panels with 12 Wp specifications showed that it will be fully charged in around 3.8 h. However, the performance of the telescopic lamp, especially in the charging process, is affected by the environment condition, such as sunlight intensity, ambient temperature, and humidity.</span></p>

Microcontroller based Multifunctional Automated Weather Monitoring and Logging System

This paper describes a microcontroller-based prototype Automated Weather Monitoring and Logging System that can col- lect meteorological data such as air temperature, relative humidity, atmospheric pressure, light intensity, and rain detection from any distant location. The Weather Monitoring and Logging System is entirely automated, and measured weather data is transferred to a public server while showing immediate data on a liquid crystal display (LCD) and stored to a Secure Digital (SD) card. For private viewers, Android-based smart phones may be interfaced with the weather station and operated via the android application. The weather station is supplied by a direct current (DC) source, with a backup rechargeable battery. In the event of an emergency power outage, the system will immediately switch to battery power. Two Atmega 328p and Two ESP 8266 microcontrollers are utilized as the core of the control and coordination of the relative multitude of exercises of the singular modules. All of the sensors in the systems have been calibrated, ensuring that the system’s accuracy seems to be exceptional. This system will benefit all users, and it will benefit the meteorological industry because it will allow them to work from a remote location. Keywords: Automated Weather Station; Microcontroller; Sensor; Meteorological Instrument

IoT Security Mechanisms in the Example of BLE

In recent years, a lot of IoT devices, wireless sensors, and smart things contain information that must be transmitted to the server for further processing. Due to the distance between devices, battery power, and the possibility of sudden device failure, the network that connects the devices must be scalable, energy efficient, and flexible. Particular attention must be paid to the protection of the transmitted data. The Bluetooth mesh was chosen as such a network. This network is built on top of Bluetooth Low-Energy devices, which are widespread in the market and whose radio modules are available from several manufacturers. This paper presents an overview of security mechanisms for the Bluetooth mesh network. This network provides encryption at two layers: network and upper transport layers, which increases the level of data security. The network uses sequence numbers for each message to protect against replay attacks. The introduction of devices into the network is provided with an encryption key, and the out-of-band (OOB) mechanism is also supported. At the moment, a comparison has been made between attacks and defense mechanisms that overlap these attacks. The article also suggested ways to improve network resiliency.