Implantable RF-coiled chip packaging

In this paper, we present an embedded chip integration technology that utilizes silicon housings and flexible parylene radio frequency (RF) coils. As a demonstration of this technology, a flexible parylene RF coil has been integrated with an RF identification (RFID) chip. The coil has an inductance of 16 μH, with two layers of metal completely encapsulated in parylene-C. The functionality of the embedded chip is verified using an RFID reader module. Accelerated-lifetime soak testing has been performed in saline, and the results show that the silicon chip is well protected and the lifetime of our parylene-encapsulated RF coil at 37 °C is more than 20 years

Wafer-Level Parylene Packaging With Integrated RF Electronics for Wireless Retinal Prostheses

This paper presents an embedded chip integration technology that incorporates silicon housings and flexible Parylene-based microelectromechanical systems (MEMS) devices. Accelerated-lifetime soak testing is performed in saline at elevated temperatures to study the packaging performance of Parylene C thin films. Experimental results show that the silicon chip under test is well protected by Parylene, and the lifetime of Parylenecoated metal at body temperature (37°C) is more than 60 years, indicating that Parylene C is an excellent structural and packaging material for biomedical applications. To demonstrate the proposed packaging technology, a flexible MEMS radio-frequency (RF) coil has been integrated with an RF identification (RFID) circuit die. The coil has an inductance of 16 μH with two layers of metal completely encapsulated in Parylene C, which is microfabricated using a Parylene–metal–Parylene thin-film technology. The chip is a commercially available read-only RFID chip with a typical operating frequency of 125 kHz. The functionality of the embedded chip has been tested using an RFID reader module in both air and saline, demonstrating successful power and data transmission through the MEMS coil

AN INVESTIGATION OF THE POSSIBILITIES OF ROOM-SCALE WIRELESS POWER TRANSFER

Inspired by original work of Nikola Tesla in resonant inductive coupling, numerous investigations are going on making wireless power transfer (WPT) application an optimum choice for various fields. By implementing the concept of non-radiative magnetically-coupled resonant circuits, it has been found that wireless power transmission is achievable at room-scale. This thesis investigates various aspects of the possibilities of room-scale wireless power transfer. Firstly, following the background of WPT systems, MATLAB-coil design, calculation of mutual inductances and Excel-calculation of WPT system performance in multi-resonator systems design tools for WPT systems are discussed for estimating the performance of numerous WPT resonator networks at room-scale. Secondly, the WPT system with two transmitters and a load receiver was simulated for measuring resonator parameters and flux-coupling coefficients between inductors using MATLAB and excel computational tools. Also, the WPT network of four-transmitter coil system was proposed to overcome the shortcomings of two-transmitter coil system xiii incapable of transmitting power efficiently at the various orientation of receiver coil. The goal of this design was to permit greater flexibility in angular position, or attitude of the receiver coil at the room space. The simulated results were found to be promising for room-scale wireless power transmission. The chapter concludes with a design validation that is efficient for a room-scale wireless power transmission. Conclusions and suggestions for future work are provided

Dual-Band Resonator Designs for Near-Field Wireless Energy Transfer Applications

Dual-band near-field wireless energy transfer (WET) designs outweigh single-band system with regard to either concurrent energy and data transfer or multiple wireless charging standard functionalities. There are two major approaches in resonator designs, namely, multi-coil and single-coil. This chapter presents a review on design constraints for each design approach and rectification techniques available in counteracting impediments of dual-band near-field WET systems. Challenges pertinent to link design are discussed primarily followed by methods implemented to mitigate detrimental impact on performance metrics. Front-end dual-band resonator design methods are accentuated in this chapter in lieu of end-to-end WET system. This is envisioned to offer insights for designers contemplating on design modes or developing ways to facilitate a boost in rectification options currently available

A Smart Implantable Bone Fixation Plate Providing Actuation and Load Monitoring for Orthopedic Fracture Healing

Fracture non-union occurs in roughly 5-10% of all fracture cases, and current interventions are both time-consuming and costly. There is therefore significant incentive to develop new tools to improve fracture healing outcomes. Several studies have shown that low-magnitude, high-frequency (LMHF) mechanical loading can promote faster healing and reduce the risk of refracture in critical-size long bone fractures. This is typically done using whole-body vibration, which may result in undesirable systemic effects on the rest of the body. This work discusses an implantable piezoelectric fixation plate that can both apply LMHF loading directly to the fracture site using flexible scheduling and indirectly monitor the progress of healing by using the increasing stiffness of the fracture callus. The design and performance of the piezoelectric bone plate show that the device can apply the target treatment and has the sensitivity to be used to observe the progress of healing. An accompanying telemetry system using BLE communication is also introduced which has a footprint of suitable size to be used in rodent studies and can provide the power necessary for piezoelectric actuation. These results pave the way for future studies regarding the efficacy and optimization of LMHF treatments in fracture healing models

Impact of Coil Misalignment in Data Transmission over the Inductive Link of an EV Wireless Charger

The penetration rate of electric vehicles (EVs) will experience a relative increment in the future, so easy to use ways to recharge will be demanded. In this sense, wireless charging represents a safe charging method that minimises user intervention. In a similar way to conductive charge, wireless charging requires some information exchange between the charger primary side and secondary side (battery) for safety and operational reasons. Thus, wireless chargers depend on a communication system for their controlled and correct operation. This paper analysed the communication performance of a wireless EV charger in which the communiction device is part of the wireless power transfer system. Particularly, this work studies how the communication system reacts to power coil displacements, which commonly occur in their conventional performance. The results show that the compensation topology selected to ensure the resonant operation clearly impacts on the communication performance. In particular, the theoretical model and the simulation results demonstrate that the asymmetrical compensation topologies are more stable in terms of the wireless communication channel capacity

Automatic Positioning System for Inductive Wireless Charging Devices and Application to Mobile Robot

Inductive power transfer (IPT) remains one of the most common ways to achieve wireless power transfer (WPT), operating on the same electromagnetic principle as electrical transformers but with an air core. IPT has recently been implemented in wireless charging of consumer products such as smartphones and electric vehicles. However, one major challenge with using IPT remains ensuring precise alignment between the transmitting and receiving coils so that maximum power transfer can take place. In literature, much of the focus is on improving the electrical circuits or IPT coil geometries to allow a greater transmission range. Nevertheless, most IPT products today rely on precise alignment for efficient power transfer. In this thesis, the use of sensing coils to detect and correct lateral misalignments in a typical IPT system is modeled and tested. The sensing coils exploit magnetic-field symmetry to give a nonlinear measure of misalignment direction and magnitude. To test this idea, three experiments are performed: 1) measure the voltage of experimental sensing coils for various lateral misalignment distances, 2) implement closed-loop control and measure performance for an experimental two-dimensional (2D) automatic IPT alignment mechanism, and 3) test automatic IPT alignment on a plausible mobile robot wireless charging scenario. The experimental sensing coils give a misalignment sensing resolution of 1 mm or less in two lateral directions, allowing automatic alignment control in real time with a maximum lateral positioning error of less than √2 mm. This precise alignment allows for efficient power transfer to occur. When implemented on the mobile robot platform, the automatic positioning system gives similar results, allowing the robot to position itself above a wireless charger precisely—a task the mobile robot cannot accomplish using its navigation camera alone. The results of this experiment give confidence that similar sensing coils can be used to reduce lateral misalignments in scaled IPT systems, such as electric-vehicle wireless chargers

Application of a Design for Excellence Methodology for a Wireless Charger Housing in Underwater Environments

A major effort is put into the production of green energy as a countermeasure to climatic changes and sustainability. Thus, the energy industry is currently betting on offshore wind energy, using wind turbines with fixed and floating platforms. This technology can benefit greatly from interventive autonomous underwater vehicles (AUVs) to assist in the maintenance and control of underwater structures. A wireless charger system can extend the time the AUV remains underwater, by allowing it to charge its batteries through a docking station. The present work details the development process of a housing component for a wireless charging system to be implemented in an AUV, addressed as wireless charger housing (WCH), from the concept stage to the final physical verification and operation stage. The wireless charger system prepared in this research aims to improve the longevity of the vehicle mission, without having to return to the surface, by enabling battery charging at a docking station. This product was designed following a design for excellence (DfX) and modular design philosophy, implementing visual scorecards to measure the success of certain design aspects. For an adequate choice of materials, the Ashby method was implemented. The structural performance of the prototypes was validated via a linear static finite element analysis (FEA). These prototypes were further physically verified in a hyperbaric chamber. Results showed that the application of FEA, together with well-defined design goals, enable the WCH optimisation while ensuring up to 75% power efficiency. This methodology produced a system capable of transmitting energy for underwater robotic applications.This work is funded by the European Commission under the European Union’s Horizon 2020—The EU Framework Programme for Research and Innovation 2014–2020, under grant agreement No. 871571 (ATLANTIS).info:eu-repo/semantics/publishedVersio

Bridges Structural Health Monitoring and Deterioration Detection Synthesis of Knowledge and Technology

INE/AUTC 10.0