Victor Farm-Guoo Tseng

Bio: Victor Farm-Guoo Tseng is an academic researcher from United States Army Research Laboratory. The author has contributed to research in topics: Wireless power transfer & Piston. The author has an hindex of 9, co-authored 26 publications receiving 249 citations. Previous affiliations of Victor Farm-Guoo Tseng include Oak Ridge Associated Universities & National Chiao Tung University.

A capacitive vibration-to-electricity energy converter with integrated mechanical switches

Abstract: Due to recent advances in low-power VLSI design technology, it has become feasible to power portable or remote electronic devices by scavenging the ambient energy. The design, fabrication and measurement of a capacitive vibration-to-electricity energy converter are presented in this paper. With a device area constraint of 1 cm2 and an auxiliary battery supply of 3.6 V, the device was designed to generate an output power of 31 µW with an output saturation voltage of 40 V. An external mass of 4 g was needed to adjust the device resonance to match the input vibration of 2.25 m s−2 at 120 Hz. Mechanical contact switches were integrated onto the device to provide accurate charge–discharge energy conversion timing. The device was fabricated in SOI (silicon-on-insulator) wafers by deep silicon etching technology. Parasitic capacitance was minimized by partial back side substrate removal. Resonant frequencies of the fabricated device with and without the external mass agreed with the expected values. Without the external mass, the measured ac output power was 1.2 µW with a load of 5 MΩ at 1870 Hz. Detailed circuit modeling and ac output power measurement of the devices with the external mass attached are in progress.

Phased Array Focusing for Acoustic Wireless Power Transfer

Abstract: Wireless power transfer (WPT) through acoustic waves can achieve higher efficiencies than inductive coupling when the distance is above several times the transducer size. This paper demonstrates the use of ultrasonic phased arrays to focus power to receivers at arbitrary locations to increase the power transfer efficiency. Using a phased array consisting of 37 elements at a distance nearly 5 times the receiver transducer diameter, a factor of 2.6 increase in efficiency was achieved when compared to a case equivalent to a single large transducer with the same peak efficiency distance. The array has a total diameter of 7 cm, and transmits through air at 40 kHz to a 1.1-cm diameter receiver, achieving a peak overall efficiency of 4% at a distance of 5 cm. By adjusting the focal distance, the efficiency can also be maintained relatively constant at distances up to 9 cm. Numerical models were developed and shown to closely match the experimental energy transfer behavior; modeling results indicate that the efficiency can be further doubled by increasing the number of elements. For comparison, an inductive WPT system was also built with the diameters of the transmitting and receiving coils equivalent to the dimensions of the transmitting ultrasonic phased array and receiver transducer, and the acoustic WPT system achieved higher efficiencies than the inductive WPT system when the transmit-to-receive distance is above 5 cm. In addition, beam angle steering was demonstrated by using a simplified seven-element 1-D array, achieving power transfer less dependent on receiver placement.

Acoustic Power Transfer and Communication With a Wireless Sensor Embedded Within Metal

Abstract: Thick metal barriers prevent the use of conventional electromagnetic wireless power transfer due to Faraday shielding effects. Here, for the first time, we demonstrate power transfer to and communication with a compact wireless sensor transponder fully embedded within a solid piece of metal through the use of ultrasonic waves. This technique is an important innovation for applications, such as structural health monitoring of solid metal structural components, which would be weakened by the presence of holes for wiring. The embedded sensor system consists of a single piezoelectric transducer used for both power and data communication, along with an energy storage unit and associated charging circuitry, as well as a representative sensor and sensor data acquisition electronics. The entire sensor transponder was packaged within a compact volume of 11.9 cm3 (0.73 in3) and can be further miniaturized to millimeter-scale sizes with the use of widely available system-on-chip technologies. The measured power transfer and sensor data results were found to closely match modeling results, achieving a power transfer efficiency of 33% at 440 kHz, showcasing the feasibility and potential of this approach.

A High-Q In-Silicon Power Inductor Designed for Wafer-Level Integration of Compact DC-DC Converters

Abstract: This paper reports the design, fabrication, and characterization of a novel power inductor embedded inside a silicon substrate and fabricated at wafer level. Such power inductors in silicon (PIiS) employ high-aspect ratio silicon molds formed with deep-reactive ion etching to obtain large cross-sectional electroplated copper windings (as thick as the silicon wafers). The PIiS also utilize high-resistivity magnetic composites as the core material, in a closed flux path manner, for small core losses and low electromagnetic interference. By using copper electroplating for all of the conductors in the component, the contact resistances between the conductive layers can be minimized and the inductors' quality factor can be improved significantly. Toward the end of the fabrication process, surface bonding pads are also formed on the PIiS, leading to a compact converter packaging with IC circuitry. A square-shaped spiral inductor (of size 3 × 3 × 0.83 mm 3 ) was successfully fabricated. Large inductance (430 nH), low dc resistance (84 mΩ), and high quality factor (21) were achieved at 6 MHz. The fabricated inductor was assembled with a TI TPS62621 buck converter IC, and it achieved a maximum power conversion efficiency of 83%.

Ultrasonic Lamb Waves for Wireless Power Transfer

Abstract: Ultrasonic guided plate waves (Lamb waves) can be used to transfer power along the length of metal plates, achieving longer distance wireless power transfer (WPT), while not being impeded by electromagnetic shielding from the metal plate. In this article, a fundamental study on the performance of Lamb wave WPT is presented, including modeling, simulations, and experimental verification. By using Macro-Fiber Composite (MFC), ${d}_{33}$ -mode, piezoelectric transducers bonded to a $64\,\,\text {mm} \times 406\,\,\text {mm} \times 1.6$ mm aluminum plate using an epoxy, power transfer of 0.47 W with 56% overall power transfer efficiency was achieved at a 204-mm distance. The measured frequency response of the power transfer efficiency matches well with the simulated results, and the effects of complex load impedance matching and transducer sizing were investigated. It is shown that the location where the efficiency is maximized roughly corresponds to the zero-order symmetrical mode (S0) standing wave patterns due to reflections from the plate edges. For practical implementation, the effect of using different methods to temporarily or permanently bond the MFC transducers to the metal plate was also investigated, as well as the effect of electrically grounding the metal plate.

MEMS Mirrors for LiDAR: A review.

Abstract: In recent years, Light Detection and Ranging (LiDAR) has been drawing extensive attention both in academia and industry because of the increasing demand for autonomous vehicles. LiDAR is believed to be the crucial sensor for autonomous driving and flying, as it can provide high-density point clouds with accurate three-dimensional information. This review presents an extensive overview of Microelectronechanical Systems (MEMS) scanning mirrors specifically for applications in LiDAR systems. MEMS mirror-based laser scanners have unrivalled advantages in terms of size, speed and cost over other types of laser scanners, making them ideal for LiDAR in a wide range of applications. A figure of merit (FoM) is defined for MEMS mirrors in LiDAR scanners in terms of aperture size, field of view (FoV) and resonant frequency. Various MEMS mirrors based on different actuation mechanisms are compared using the FoM. Finally, a preliminary assessment of off-the-shelf MEMS scanned LiDAR systems is given.

Apparatus for transmitting electrical energy inductively

Abstract: Disclosed is an apparatus for inductively transferring power to movable consumer, it extends in the form of a conductor loop along a trajectory of a predetermined consumer, disposed on the consumer it is capable of power therefrom drawn by the secondary conductor, comprising at least one primary conductor. To produce a simple and inexpensive variable route layout, the device, galvanically (galvanically) isolated two conductor loops are provided, it is assigned to different sectors of the track Te, so that it can be power distributed to the consumer that is transmitted by inductive coupling conductor loop to at least one second conductor loop from the first conductor loop is arranged relative to each other . Sectors of the two conductor loops which is inductively coupled to form a transformer, which is preferably provided with a two-piece ferromagnetic core. Movable consumer is guided on a rail, one sector of the inductively coupled by conductor loop, the movable portion of the rail switch with only such binding occurs last position of the rail switch with, It is connected.

A review on heat and mechanical energy harvesting from human – Principles, prototypes and perspectives

Abstract: The rapid development of smart electronics has enabled their applications into such fields as portable instruments, wearable electronic devices, implantable medical devices and even assistive biomedical devices. As a result, power requirements of these devices continuously increase to such a degree that currently used batteries can not meet. Recently the heat and mechanical energy available in human daily activities have received increasing attention by researchers as alternatives. This paper looks into the physical mechanisms, materials and devices involved in possible energy harvesting from human motion. Heat and mechanical energy available in human daily activities are summarized to give an overview of the potential of energy harvesting from human motion. In addition, different energy transducing principles are discussed. Moreover, various proposed or demonstrated energy harvesting prototypes related to human motion are reviewed and discussed with respect to their working principles, device structures, implementations and performances. Finally, trends, challenges, applications and future developments of energy harvesting from human motion are discussed.

Power generation for wearable systems

Abstract: Wearable devices are drawing increasing attention in both academia and industry in that they can offer unprecedented information related to human health in real-time and human–machine interactions, which is expected to enable a paradigm shift in the digital world. For this shift to occur, green and sustainable energy technology for powering flexible wearable devices is a roadblock. This paper is dedicated to reviewing cutting-edge wearable power generation methodologies, for which we discuss their pros and cons, underlying physics, and general design/evaluation criteria. Sensor types, materials, processing technology, power consumption, and methods of testing the stretchability and flexibility of wearable devices are also summarized. Based on application scenarios in healthcare, industrial inspection, structural monitoring, armed forces and consumer electronics, an integrated system architecture of wearable, flexible systems is presented. Finally, future perspectives of wearable technologies are outlined by covering the aspects of all-in-one printable wearable electronics, fiber and textile electronics, self-powered self-awareness wearable systems, hybrid-integrated Systems on a Chip (SoC) for flexible electronics, and Internet of Things (IoT)-enabled self-contained systems towards full life cycle monitoring.