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The purpose of this paper is to present the design of a piezoelectric vibration energy generator with a power conditioning circuit to power a wireless sensor node. Frequency and voltage characterization of the piezoelectric energy harvester is performed. A single-stage AC–DC power converter that integrates the rectification and boosting circuit is designed, simulated and implemented in hardware.

The designed power conditioning circuit incorporates bridgeless boost rectification, a lithium ion battery as an energy storage unit and voltage regulation to extract maximum power from PZT-5H and to attain higher efficiency. The sensor node is modelled in active and sleep states on the basis of the power consumption. Dynamic modelling of the lithium ion battery with its state of charging and discharging is analysed.

The test result shows that the energy harvester produces a maximum power of 65.9 mW at the resonant frequency of 21.4 Hz. The designed circuit will operate even at a minimum input voltage of 0.5 V. The output from the harvester is rectified, boosted to a 7-V DC output and regulated to 3.3 V to the power C_Mote wireless sensor node. The conversion efficiency of the circuit is improved to 70.03 per cent with a reduced loss of 19.76 mW.

The performance of the energy harvester and the single-stage power conditioning circuit is analysed. Further, the design and implementation of the proposed circuit lead to an improved conversion efficiency of 70.03 per cent with a reduced loss of 19.76 mW. The vibration energy harvester is integrated with a power conditioning circuit to power a wireless sensor node C_Mote. The piezoelectric vibration energy harvester is implemented in real time to power C_Mote.

This paper aims to present the design of a cantilever beam with various kinds of geometries for application in energy harvesting devices with a view to enhance the harvested power. The cantilever beams in rectangular, triangular and trapezoidal geometries are simulated, designed and evaluated experimentally. A power conditioning circuit is designed and fabricated for rectification and regulation.

The analytical model based on Euler–Bernoulli beam theory is analyzed for various cantilever geometries. The aluminum beam with Lead Zirconate Titanate (PZT) 5H strip is used for performing frequency, displacement, strain distribution, stress and potential analysis. A comparative analysis is done based on the estimated performance of the cantilevers with different topologies of 4,500 mm³ volume.

The analysis shows the trapezoidal cantilever yielding a maximum voltage of 66.13 V at 30 Hz. It exhibits maximum power density of 171.29 W/mm³ at optimal resistive load of 330 kΩ. The generated power of 770.8 µW is used to power up a C-mote wireless sensor network.

This study provides a complete structural analysis and implementation of the cantilever for energy harvesting application, integration of power conditioning circuit with the energy harvester and evaluation of the designed cantilevers under various performance metrics.

The purpose of this research paper is to explore the possibility to enhance the power transfer from piezoelectric energy harvester (PEH) source to the load. As the proposed gyrator-induced voltage flip technique (GIVFT) does not require bulky components such as physical inductors, it is easily realizable in small integrated circuits (IC) package thereby offering performance benefits, reducing area overhead and providing cost benefits for constrained self-powered autonomous Internet-of-Things (IoT) applications.

This paper presents an inductorless interface circuit for PEH. The proposed technique is called GIVFT and is demonstrated using active elements. The authors use gyrator to induce voltage flip at the output side of PEH to enhance the charge extraction from PEH. The proposed technique uses the current-voltage (I-V) relationship of gyrator to get appropriate phasor response necessary to induce the voltage flip at the output of PEH to gain power transfer enhancement at the load.

The experimental results show the efficacy of the GIVFT realization for enhanced power extraction. The authors have compared their proposed design with popular earlier reported interface circuits. Experimentally measured performance improvement is 1.86×higher than the baseline comparison of full-wave bridge rectifier circuit. The authors demonstrated a voltage flip using GIVFT to gain power transfer improvement in piezoelectric energy harvesting.

To the best of the authors’ knowledge, pertaining to the field of PEH, this is the first reported GIVFT based on the I-V relationship of the gyrator. The proposed approach could be useful for constrained self-powered autonomous IoT applications, and it could be of importance in guiding the design of new interface circuits for PEH.

The purpose of this paper is to demonstrate the feasibility of using kinetic energy harvesting to power wireless condition monitoring sensors.

The system presented duty cycles its operation depending upon the energy being harvested. The harvested energy is stored on a supercapacitor and the system samples sufficient vibration data to enable an FFT to be performed at the receiver.

The results of this study show it is perfectly feasible to power practical wireless condition monitoring sensors entirely from the vibrations of the machines being monitored.

Energy harvesting techniques can be used to power wireless sensors in a range of applications. Removing the need for a battery power supply presents obvious environmental benefits and avoids the need to periodically replace batteries.

To describe the design methodology and human‐centre functionality of the whole arm manipulator (WAM) developed originally at MIT and brought to commercial fruition by Barrett Technology.

The WAM arm is driven by cable‐and‐cylinder transmissions, which uniquely exhibits zero backlash with low friction and low inertia, endowing the WAM with good open‐loop “backdrivability”. Two key benefits of the high backdrivability are: motion control through joint torque control, which enables the intrinsic sensing of forces over the whole arm and makes it inherently safe to humans; operation directly in the Cartesian domain without the need for inverse kinematics calculations, providing very rapid responsiveness as demonstrated in the “baseball robot” of Tokyo University. Another benefit of the WAM is its kinematic redundancy through the 4‐dof (degrees‐of‐freedom) main axes (7‐dof with the wrist). Recent major advances in the WAM include the “puck”, the world's smallest fully‐featured servo‐controller that eliminates the need for an external controller cabinet, and a safety circuit that limits, by a set amount, the power flow from the WAM to a person or object while not inhibiting the reverse from human to arm. The WAM's intrinsic force control has allowed the development of software‐defined haptic walls, which are being exploited by partners such as the CMU (Carnegie Mellon University) Robotics Institute, in patient rehabilitation, and Mako Surgical, for use in joint surgery.

The Barrett WAM's good open‐loop backdrivability has initiated the development of novel human‐centred robot applications that will expand the use of robots outside the factory and into human‐inhabited areas.

Presents the design methodology, features and applications of the Barrett WAM human‐centred robot.

This paper intent to design, develop, and fabricate a robust cascaded controller based on the dual loop concept i.e. Fuzzy Sliding Mode concept in the inner loop and traditional Proportional Integral controller in the outer loop to reduce the unknown dynamics and disturbances that occur in the DC-DC Converter.

The proposed Fuzzy sliding mode approach combines the merits of both SMC and Fuzzy logic control. FSMC approach reduces the chattering phenomena that commonly occurs in the sliding mode control and speed up the response of the controller.

In most of the research work, the inner current loop of cascaded controller was designed by sliding mode control. In this paper FSMC is proposed and its efficacy is confirmed with SMC -PI. In most uncertainties, FSMC-PI produces null maximum peak overshoot and a very less settling time of 0.0005 sec.

The presence of Fuzzy SMC in the inner loop ensure satisfactory response against all uncertainties such as steady state, circuit parameter variations and sudden line and load disturbances.

Presents a new approach for formulating the state space equations associated with electrical systems containing circuits which are coupled only magnetically. Presents an algorithm which automatically determines the state space matrix of a system which can take any topological form. Describes a new way of representing semiconductor devices which gives increased flexibility in system representation, and reduces computation time, together with a technique for satisfactorily accounting for the discontinuous behaviour of semiconductor devices. Illustrates the application of the proposed technique by means of a relatively simple example for which an analytical solution is possible. Compares illustrative test results obtained from more complex circuits with those from simulation to demonstrate further the validity of the method.

This paper aims to present a comparison between three types of manufacturing techniques, namely, screen-printed, inkjet and gravure, using different types of inks, for the implementation of concentric ring electrodes which permit estimation of Laplacian potential on the body surface.

Flexible concentric ring electrodes not only present lower skin–electrode contact impedance and lower baseline wander than rigid electrodes but are also less sensitive to interference and motion artefacts. The above three techniques allow printing of conductive inks on flexible substrates, and with this work, the authors aim to study which is the best technique and ink to obtain the best electrode response.

From the results obtained regarding ink thickness, resistivity, electrode resistance and other performance parameters derived from electrocardiographic signal recording tests, it can be said that concentric electrodes using the screen-printing and inkjet techniques are suitable for non-invasive bioelectric signal acquisition.

The development of new types of inks and substrates for the electronics industry and the adaptation of new manufacturing techniques allow for an improvement in the development of electrodes and sensors.

The automatic pilot is probably the first application the layman thinks of in terms of electronics and flight control. However, the extensive part now played by electronics in achieving good handling/controllability and performance is becoming increasingly important as the technology is now sufficiently mature for extensive use to be made of automatic control techniques.

Uninterruptible Power Supply (UPS) systems are typically designed to provide power to computers for five to thirty minutes after all utility company power has failed. In addition to providing blackout and brownout protection, many UPS systems also protect against spikes, surges, sags, and noise, and some also offer many of the features found in power distribution units (PDUs). The major components or subsystems of a typical UPS system are detailed, and a sample bid specification is appended. Three sidebars discuss UPSs and air conditioning, the maintenance bypass switch (MBS), and literature for further reading.