A Carrier Signal Approach for Intermittent Fault Detection and Health Monitoring for Electronics Interconnections System

Abstract: Intermittent faults are completely missed out by traditional monitoring and detection techniques due to non-stationary nature of signals. These are the incipient events of a precursor of permanent faults to come. Intermittent faults in electrical interconnection are short duration transients which could be detected by some specific techniques but these do not provide enough information to understand the root cause of it. Due to random and non-predictable nature, the intermittent faults are the most frustrating, elusive, and expensive faults to detect in interconnection system. The novel approach of the author injects a fixed frequency sinusoidal signal into electronics interconnection system that modulates intermittent fault if persist. Intermittent faults and other channel effects are computed from received signal by demodulation and spectrum analysis. This paper describes technology for intermittent fault detection, and classification of intermittent fault, and channel characterization. The paper also reports the functionally tests of computational system of the proposed methods. This algorithm has been tested using experimental setup. It generate an intermittent signal by external vibration stress on connector and intermittency is detected by acquiring and processing propagating signal. The results demonstrate to detect and classify intermittent interconnection and noise variations due to intermittency. Monitoring the channel in-situ with low amplitude, and narrow band signal over electronics interconnection between a transmitter and a receiver provides the most effective tool for continuously watching the wire system for the random, unpredictable intermittent faults, the precursor of failure. - See more at: http://thesai.org/Publications/ViewPaper?Volume=6&Issue=12&Code=ijacsa&SerialNo=20#sthash.8RXsdW0t.dpu

Intermittent fault diagnosis and health monitoring for electronic interconnects

Literature survey and correspondence with industrial sector shows that No-Fault-Found (NFF) is a major concern in through life engineering services, especially for defence, aerospace, and other transport industry. There are various occurrences and root causes that result in NFF events but intermittent interconnections are the most frustrating. This is because it disappears while testing, and missed out by diagnostic equipment. This thesis describes the challenging and most important area of intermittent fault detection and health monitoring that focuses towards NFF situation in electronics interconnections. After introduction, this thesis starts with literature survey and describes financial impact on aerospace and other transport industry. It highlights NFF technologies and discuss different facts and their impact on NFF. Then It goes into experimental study that how repeatedly intermittent fault could be replicated. It describes a novel fault replicator that can generate repeatedly IFs for further experimental study on diagnosis techniques/algorithms. The novel IF replicator provide for single and multipoint intermittent connection. The experimental work focuses on mechanically induced intermittent conditions in connectors. This work illustrates a test regime that can be used to repeatedly reproduce intermittency in electronic connectors whilst subjected to vibration ... [cont.]

Design and control of a cellular architecture-based adaptive wiring manifold

Existing spacecraft wiring harnesses utilize fixed wiring harness architectures, consisting of either bundles of physical wires, electrical components with backplanes, or motherboard/card arrangements. All such designs are generally configured at manufacture and require significant rework when mission requirements change. A programmable wiring harness is proposed and implemented that, like a field programmable gate array (FPGA), is a pre-built switch fabric that is soft-configured at the time of use, and adapted in real time as components to be wired are added. By providing reversible and dynamically programmable software wires, when embedded in a wiring system, these can be used to build a programmable wiring manifold. The useful properties of this adaptive wiring system include design time reduction by orders of magnitude over traditional wiring harness implementations, the potential of self-healing/diagnostics, and soft-definable probe signals to aid in discovery of component faults. Algorithms used in FPGA routing are exploited to guide the formation of switchable wire paths in the adaptive wiring manifold. A physical system is implemented in this thesis that demonstrates the concepts of substrate/cell creation, master routing control and graph creation, and wiring commands generated and transmitted to the cell substrate in order to route electrical connections based on gathered netlists of detected components

Modeling fabrication and characterization of a bio-micro thermoelectric device for highly localized temperature control

There is an ever expanding interaction between the fields of micro-electromechanical systems (MEMS) and biology to develop devices to monitor, control and act on living systems. Particularly in the field of cryobiology, there is a need to monitor and control temperature at the cellular level. An important step towards achieving this aim is to fabricate an array of microscale thermoelectric actuators. As a first step for towards achieving such localized control of temperatures in cells and tissues, an array of individually addressable micro-thermoelectric coolers (µTECs) were modeled, characterized, and fabricated. Prefabrication experimentation and modeling were carried out to understand the behavior of the device. Two mathematical models, the lumped parameter model and finite element model, were used to identify important device parameters and dimensions. The organization of the proposed device was an array of 4 x 4 microscale (~10 ìm) thermoelectric actuators, each of which was separated by a distance of 50 ìm center-to-center and dimensioned so that each µTEC could measure or modulate the temperature in the neighborhood of a single cell. The prefabrication experiments showed that it was feasible to produce the TECs required for fabrication of the device through electrodeposition. Bismuth-telluride was electrodeposited to form the n-type and p-type leg elements of µTEC and the deposition was achieved by varying the cathodic potential. The material deposition development could focus on a single material system, yielding both n-type, and p-type pellets of TEC. The prototype devices were successfully fabricated with a modified multi-step LIGA (Lithographie, Galvanoformung and Abformung) technique wherein a patterned positive photoresist and photomasks defined the geometry of the device. This enables high-density wiring required for the device. In future, these µTECs will be embedded in Polymethylmethacrylate (PMMA) matrix to improve insulation. An artificial tissue (AT) system composed of Normal Human Dermal Fibroblast (NHDF) cells from stem cells will be grown on the device for experimentation wherein a PMMA sheet will act as an interface between the cooler and the embedded cells. The thermoelectric micro device thus developed will result in the unique capability of temperature manipulation and control on cellular scales (micrometers)

Interconnect yield analysis and fault tolerance for field programmable gate arrays

Imperial Users onl

Nanochips and medical applications

Ο όρος «νανοτσιπ» αναφέρεται σε ένα ολοκληρωμένο κύκλωμα (τσιπ) με νανοϋλικά και δομές στη νανοκλίμακα (1-100nm). Ένα ολοκληρωμένο κύκλωμα είναι μια συλλογή ηλεκτρονικών εξαρτημάτων, όπως τρανζίστορ, δίοδοι, πυκνωτές και αντιστάσεις. Τα σημερινά τρανζίστορ είναι στη νανοκλίμακα, αλλά μπορούν να τροποποιηθούν με νανοδομές για την κατασκευή βιοαισθητήρων που μπορούν να πραγματοποιούν ανίχνευση βιομορίων, όπως ιόντα, μόρια DNA, αντισώματα και αντιγόνα με μεγάλη ευαισθησία. Υλικά και Μέθοδοι: Πραγματοποιήθηκε συστηματική αναζήτηση βιβλιογραφίας με χρήση των ηλεκτρονικών βάσεων δεδομένων PubMed, Google Scholar και Scopus για την ανάπτυξη και χρήση νανοτσίπ σε ιατρικές εφαρμογές. Για τον προσδιορισμό των σχετικών εργασιών, τα κριτήρια συμπερίληψης αναφέρονται σε άρθρα στην αγγλική γλώσσα, άρθρα βιβλιογραφικού περιεχομένου ή/και έρευνών. Τα κριτήρια αποκλεισμού ήταν άρθρα εφημερίδων, περιλήψεις συνεδρίων και επιστολές. Αποτελέσματα: Τεχνικές in-vivo και in-vitro έχουν χρησιμοποιηθεί για την ανίχνευση μορίων DNA, ιόντων, αντισωμάτων, σημαντικών πρωτεϊνών και καρκινικών δεικτών, όχι μόνο από δείγματα αίματος αλλά και από ιδρώτα, σάλιο και άλλα βιολογικά υγρά. Διαγνωστική εφαρμογή των νανοτσίπ αποτελεί και η ανίχνευση πτητικών οργανικών ενώσεων μέσω τεστ εκπνεόμενης αναπνοής. Υπάρχουν και αρκετές θεραπευτικές εφαρμογές αυτών των συσκευών ημιαγωγών όπως τσιπ διασύνδεσης εγκεφάλου-υπολογιστή για παραλυτικές ή επιληπτικές καταστάσεις, κατασκευή «βιονικών» οργάνων όπως τεχνητός αμφιβληστροειδής, τεχνητό δέρμα και ρομποτικά προθετικά άκρα για ακρωτηριασμένους ή ρομποτική χειρουργική. Συμπέρασμα: Η χρήση των νανοτσίπ στην ιατρική είναι ένας αναδυόμενος τομέας με αρκετές θεραπευτικές εφαρμογές όπως η διάγνωση, η παρακολούθηση της υγείας και της φυσικής κατάστασης και η κατασκευή «βιονικών» οργάνων.Background: The term “nanochip” pertains to an integrated circuit (chip) with nanomaterials and components in the nano-dimension (1-100nm). An integrated circuit is essentially a collection of electronic components, like transistors, diodes, capacitors, and resistors. Current transistors are in the nanoscale but can also be modified with nanostructures like nanoribbons and nanowires to manufacture biosensors that can perform label-free, ultrasensitive detection of biomolecules like ions, DNA molecules, antibodies and antigens. Materials and Methods: A systematic literature search was conducted using the electronic databases PubMed, Google Scholar and Scopus for the development and use of nanochips in medical applications. For the identification of relevant papers, the inclusion criteria referred to articles in the English language, review and/or research articles. The exclusion criteria were newspaper articles, conference abstracts and letters. Results: In-vivo and In-vitro techniques have been used for detection of DNA molecules, ions, antibodies, important proteins, and tumor markers, not only from blood samples but also from sweat, saliva and other biological fluids. Another diagnostic application of nanochips is detection of volatile organic compounds via a breath test. There are also several therapeutic applications of these semiconductor devices like brain-computer interface chips for paralytic or epileptic conditions, manufacture of “bionic” organs like artificial retinas, artificial skin and robotic prostheses for amputees or robotic surgery. Conclusion: The use of nanochips in medicine is an emerging field with several therapeutic applications like diagnostics, health and fitness monitoring, and manufacture of “bionic” organs

Emerging technologies and future trends in substation automation systems for the protection, monitoring and control of electrical substations

Tese de Mestrado Integrado. Engenharia Electrotécnica e de Computadores (Automação). Faculdade de Engenharia. Universidade do Porto. 201

Detection of Interconnect Failure Precursors using RF Impedance Analysis

Many failures in electronics result from the loss of electrical continuity of common board-level interconnects such as solder joints. Measurement methods based on DC resistance such as event detectors and data-loggers have long been used by the electronics industry to monitor the reliability of interconnects during reliability testing. DC resistance is well-suited for characterizing electrical continuity, such as identifying an open circuit, but it is not useful for detecting a partially degraded interconnect. Degradation of interconnects, such as cracking of solder joints due to fatigue or shock loading, usually initiates at an exterior surface and propagates towards the interior. A partially degraded interconnect can cause the RF impedance to increase due to the skin effect, a phenomenon wherein signal propagation at frequencies above several hundred MHz is concentrated at the surface of a conductor. Therefore, RF impedance exhibits greater sensitivity compared to DC resistance in detecting early stages of interconnect degradation and provides a means to prevent and predict an important cause of electronics failures. This research identifies the applicability of RF impedance as a means of a failure precursor that allows for prognostics on interconnect degradation based on electrical measurement. It also compares the ability of RF impedance with that of DC resistance to detect early stages of interconnect degradation, and to predict the remaining life of an interconnect. To this end, RF impedance and DC resistance of a test circuit were simultaneously monitored during interconnect stress testing. The test vehicle included an impedance-controlled circuit board on which a surface mount component was soldered using two solder joints at the end terminations. During stress testing, the RF impedance exhibited a gradual non-linear increase in response to the early stages of solder joint cracking while the DC resistance remained constant. The gradual increase in RF impedance was trended using prognostic algorithms in order to predict the time to failure of solder joints. This prognostic approach successfully predicted solder joint remaining life with a prediction error of less than 3%. Furthermore, it was demonstrated both theoretically and experimentally that the RF impedance analysis was able to distinguish between two competing interconnect failure mechanisms: solder joint cracking and pad cratering. These results indicate that RF impedance provides reliable interconnect failure precursors that can be used to predict interconnect failures. Since the performance of high speed devices is adversely affected by early stages of interconnect degradation, RF impedance analysis has the potential to provide improved reliability assessment for these devices, as well as accurate failure prediction for current and future electronics

Research in the effective implementation of guidance computers with large scale arrays Interim report

Functional logic character implementation in breadboard design of NASA modular compute