Advanced detection, isolation, and accommodation of sensor failures in turbofan engines: Real-time microcomputer implementation

The objective of the Advanced Detection, Isolation, and Accommodation Program is to improve the overall demonstrated reliability of digital electronic control systems for turbine engines. For this purpose, an algorithm was developed which detects, isolates, and accommodates sensor failures by using analytical redundancy. The performance of this algorithm was evaluated on a real time engine simulation and was demonstrated on a full scale F100 turbofan engine. The real time implementation of the algorithm is described. The implementation used state-of-the-art microprocessor hardware and software, including parallel processing and high order language programming

Testing high resolution SD ADC’s by using the noise transfer function

A new solution to improve the testability of high resolution SD Analogue to Digital Converters (SD ADC’s) using the quantizer input as test node is described. The theoretical basis for the technique is discussed and results from high level simulations for a 16 bit, 4th order, audio ADC are presented. The analysis demonstrates the potential to reduce the computational effort associated with test response analysis versus conventional techniques

Hybrid receiver study

The results are presented of a 4 month study to design a hybrid analog/digital receiver for outer planet mission probe communication links. The scope of this study includes functional design of the receiver; comparisons between analog and digital processing; hardware tradeoffs for key components including frequency generators, A/D converters, and digital processors; development and simulation of the processing algorithms for acquisition, tracking, and demodulation; and detailed design of the receiver in order to determine its size, weight, power, reliability, and radiation hardness. In addition, an evaluation was made of the receiver's capabilities to perform accurate measurement of signal strength and frequency for radio science missions

Doctor of Philosophy

dissertationAdvancements in process technology and circuit techniques have enabled the creation of small chemical microsystems for use in a wide variety of biomedical and sensing applications. For applications requiring a small microsystem, many components can be integrated onto a single chip. This dissertation presents many low-power circuits, digital and analog, integrated onto a single chip called the Utah Microcontroller. To guide the design decisions for each of these components, two specific microsystems have been selected as target applications: a Smart Intravaginal Ring (S-IVR) and an NO releasing catheter. Both of these applications share the challenging requirements of integrating a large variety of low-power mixed-signal circuitry onto a single chip. These applications represent the requirements of a broad variety of small low-power sensing systems. In the course of the development of the Utah Microcontroller, several unique and significant contributions were made. A central component of the Utah Microcontroller is the WIMS Microprocessor, which incorporates a low-power feature called a scratchpad memory. For the first time, an analysis of scaling trends projected that scratchpad memories will continue to save power for the foreseeable future. This conclusion was bolstered by measured data from a fabricated microcontroller. In a 32 nm version of the WIMS Microprocessor, the scratchpad memory is projected to save ~10-30% of memory access energy depending upon the characteristics of the embedded program. Close examination of application requirements informed the design of an analog-to-digital converter, and a unique single-opamp buffered charge scaling DAC was developed to minimize power consumption. The opamp was designed to simultaneously meet the varied demands of many chip components to maximize circuit reuse. Each of these components are functional, have been integrated, fabricated, and tested. This dissertation successfully demonstrates that the needs of emerging small low-power microsystems can be met in advanced process nodes with the incorporation of low-power circuit techniques and design choices driven by application requirements

IUS/payload communication system simulator configuration definition study

The requirements and specifications for a general purpose payload communications system simulator to be used to emulate those communications system portions of NASA and DOD payloads/spacecraft that will in the future be carried into earth orbit by the shuttle are discussed. For the purpose of on-orbit checkout, the shuttle is required to communicate with the payloads while they are physically located within the shuttle bay (attached) and within a range of 20 miles from the shuttle after they have been deployed (detached). Many of the payloads are also under development (and many have yet to be defined), actual payload communication hardware will not be available within the time frame during which the avionic hardware tests will be conducted. Thus, a flexible payload communication system simulator is required

ESTCube-2 asendi ja orbiidi juhtimissüsteemi prototüübi disain

Esimene Eesti satelliit ESTCube-1 viidi edukalt maalähedasele orbiidile 2013. aasta maikuus ning aasta vältel on satelliit täitnud peaaegu kõik oma eesmärgid välja arvatud päikesepurje eksperiment [7]. Eksperimendi jooksul pannakse satelliit pöörlema kiirusega 1 pööre sekundis, keritakse 10 m pikkune mikrojuhe välja ning laetakse see kõrge potentsiaalini. Teoreetiliselt peaks laetud mikrojuhtme ja Maa ionosfäärilise plasma vastasmõju toimel satelliidi pöörlemiskiirus kahanema [14]. Kuigi missioon pole veel lõppenud, plaanitakse juba Eesti Tudengisatelliidi programmi raames järgmisi missioone [11]. Üks ESTCube-2 ja ESTCube-3 missioonide eesmärkidest on jätkata päikesepurje testimist, kasutades 1 km pikkusega mikrojuhet. Teiseks eesmärgiks on demonstreerida NanoSpace Cold Gas thruster'i kasutamist asendi ja orbiidi juhtimissüsteemi mootorina [12]. Mõlemat meetodit saab potentsiaalselt kasutada kosmoses reisimiseks [13]. Magistritöö jooksul arendati uut satelliidi asendi ja orbiidi juhtimissüsteemi, mis on hädavajalik missioonide teaduslike eesmärkide täitmiseks. Magistritöö eesmärkideks oli: • tuua välja nõuded ESTCube-2 asendi ja orbiidi juhtimissüsteemi jaoks; • kirjeldada süsteemi struktuuri; • tuua välja nõuded satelliidi asendi ja orbiidi juhtimissüsteemi prototüüpplaadi jaoks; • valida riistavara prototüüpplaadi jaoks; • arendada satelliidi asendi ja orbiiti juhtimissüsteemi esimene prototüüpplaat. Prototüüpplaadi konstuktsioon põhineb ESTCube-1 asendi juhtimissüsteemil ja ESTCube meeskonna kogemustel. Tulevalt uute missioonide poolt esitatavatest nõuetest on vajalik ka täiendava riistvara lisamine ning süsteemi suurema jõudluse garanteerimine. On analüüsitud teiste nanosatelliitide lahendused. Töö jooksul oli valitud uued elektroonikakomponendid ja kasutatud uued konstruktsioonilahendusi, mis välistavad ESTCube-1 konstruktsioonis leitud puudusi. Tulemuseks on saadud kõikidele nõudmistele vastav prototüüpplaadi konstuktsioon. Prototüüpplaat võimaldab välja lülitada kõik andurid ühe kaupa, võimaldab korraga läbi testida valikut sobivaid andureid ja võimaldab efektiivselt testida vajalikke riistvara- ja tarkvarakomponente. Töö tulemuseks on prototüüpplaadi konstuktsioon, mida on valmis kokkumonteerimiseks ja testimiseks. Seega peale magistritöö esitamist kavatseb autor tööd jätkata ning arendada tarkvara konstrueeritud platvormi jaoks

A 10MHz flash analog-to-digital converter system for digital oscilloscope and signal processing applications

Call number: LD2668 .T4 1985 S246Master of Scienc

Microbial load monitor

A card configuration which combines the functions of identification, enumeration and antibiotic sensitivity into one card was developed. An instrument package was designed around the card to integrate the card filling, incubation reading, computation and decision making process into one compact unit. Support equipment was also designed to prepare the expandable material used in the MLM

High Speed, High Current Monitoring System

Electronics testing requires lengthy data collection and analysis. Streamlining at least part of this process allows resource reallocation, and faster data processing. Verifying a signal’s efficiency is key specification for a component’s datasheet. This project focuses on streamlining data collection when measuring a device’s output current. It combines amplifier design and digital interfacing to perform monitor a device’s output current. A computer-enable interface displays a graphical output current representation. It ensures accurate, high speed, high current measurements while removing a person’s need to manually plot data after testing. A new testing method provides room for company and product growth with eased data collection and analysis methods

Advanced sensors technology survey

This project assesses the state-of-the-art in advanced or 'smart' sensors technology for NASA Life Sciences research applications with an emphasis on those sensors with potential applications on the space station freedom (SSF). The objectives are: (1) to conduct literature reviews on relevant advanced sensor technology; (2) to interview various scientists and engineers in industry, academia, and government who are knowledgeable on this topic; (3) to provide viewpoints and opinions regarding the potential applications of this technology on the SSF; and (4) to provide summary charts of relevant technologies and centers where these technologies are being developed