David Rafferty Email & Phone Number

Houston, Texas, Us

Senior Avionics EngineerAvionics lead for the Bishop Airlock Project. Other responsibilities included the Airlock Trash Deployer avionics, the Naroracks Cubesat Launcher (external), and the Nanoracks Interchangeable Cubesat Launcher

Webster, Tx, Us

1st Detect is a wholly owned subsidiary of Astrotech Corp that is commercializing a miniature chemical detector for a variety of applications including security, process monitoring, healthcare diagnostics, and industrial control.1st Detect Corp, Founder and CTO: Matured the SPACEHAB, Inc (Astrotech Corp) mass spectrometer side project into Astrotech Corp’s largest business divisionAuthored 25+ patent applications for 1st Detect, resulting in over 16 US and 10 foreign patents granted to date. Patents cover innovations in electronics, sample inlets, ion trap design, ion trap control, calibration hardware and methods, complex waveform generation and noise suppression.Head architect and manager of the MMS-1000 Miniature Mass Spectrometer development• Miniature chemical detection system at a fraction of the size, weight, and power consumption of similar performing products.• MMS-1000 development led to two large government development projects: NGCD chemical warfare agent detection for the joint armed forces, and the DHS airport security development program.

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Director of the Avionics department: Responsible for all aspects of the avionics portion of the SPACEHAB Module which operated successfully on Space Shuttle flights STS-116 and STS-118.

Lead electrical design engineer for the development of the Fiber Optic Sensing System (FOSS) used to read the wavelengths of fiber optic strain sensors called Fiber Bragg Gratings. Performed electronics design and PCB layout as well as wrote the VHDL code. The FOSS achieved a high signal to noise ratio while operating at a significantly low power and small size.Developed a high phase-margin driver circuit for the high electrical capacitance tunable wavelength filter that could drive the capacitive load accurately and with high stability.Conceived and implemented a method to automatically correct for errors induced by the length of the optical fiber without actually knowing the optical fiber length. Patent submittedHolstein Oil Platform Project: Co-wrote proposal that led to ATI participation in the Holstein and Thunder Horse projects. Selected and solved integration problems for Holstein Inclinometer. Wrote specifications for Fiber Bragg Grating sensors and performed vendor evaluation and selection. Performed system qualification testing in Denmark, and devised modifications to existing sensor interrogation electronics to reduce noise and increase dynamic range.Thunder Horse Oil Platform Project: Conceived and developed a pressure balancing technique to prevent optical sensor attenuations at extreme hydrostatic pressure (> 6000 feet below sea level). A fiber optic sensor system using this method is currently operational at the ocean floor below the Thunder Horse oil platform and measures strain temperature and internal oil riser pressure at the touch down zone. Patent submitted for pressure balancing technique.Characterized Fiber Bragg Grating response down to cryogenic temperatures. Tested upper temperature limits of various optical fibers. Investigated causes and mitigation techniques of birefringence on optical sensors, developed innovative methods for mounting Fiber Bragg Grating sensors.

Houston, Texas, Us

Lead electrical engineer for the design of the Trace Gas Analyzer (TGA.) The TGA is a hand-held mass spectrometer used by astronauts during a spacewalk to locate leaks of Ammonia or Hydrazine from the Space Station. Performed electronics miniaturization and integration with JPL instruments. Designed digital and analog electronics including Power Conditioning Module, Signal Conditioning Module and FPGA based video translator for display screen.Completed the electronics (PIC microcontroller based) and software (C++) design of the Oceaneering Spacehab Refrigerator Freezer (OSRF), which flew successfully on John Glenn’s Space Shuttle flight STS-95. The OSRF is a thermoelectric device based refrigerator freezer for use in the Space Shuttle, SPACEHAB module, or Space Station primarily for protein crystal growth research. Provided electronics design for the EVA Ohmmeter Assembly (EOA) and the International Fuel Cell Accumulator projects for the Space Station including modifications, which allowed both to pass space flight EMI testing.Designed the G-loader electronics. The G-loader is a medical research device used to load proteins into live cells. The G-loader incorporates an Ultra-capacitor power supply and an accelerometer that controls its actuation in a centrifuge.Robonaut project: Investigated using fiber optic sensing techniques for tactile sensing in Robonaut’s fingers.

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Promoted to Head of all avionics systems at Space Industries after the third flight of the Wake Shield Facility (WSF) satellite. Supervisor of all electrical engineers and technicians, in charge of all testing related to electrical systemsSole developer for the attitude control system Scan Filter for flight III of the WSF satellite which allowed the satellite to be successfully deployed during STS-80 despite corrupted attitude determination data. The Scan Filter is a microprocessor system (assembly code) which analyzes infra-red horizon scan data and digitally filters false signals using IIR and windowing filter techniques to allow correct orientation of spacecraft despite erroneous data from the attitude determination system. Telemetry from the scan filter also provided insight into design issues with the satellite’s attitude determination system. Nominated for the Rotary National Award for Space Achievement (RNASA) for designing the Scan Filter.Designed and coded the Heater Power Distribution Unit (HPDU) for flight II of the WSF satellite. The HPDU is an 87C51 microprocessor system which controls power relays and measures power system currents and voltages for the satellite. The HPDU employs high precision battery power monitoring (voltage and current, and state of charge).Designed and coded the Temperature Measurement Card (TMC) for flight III of the WSF satellite. The TMC is a microntroller based system that measures satellite temperatures with thirty multiplexed thermistors that actively adjusts thermistor current to increase measurement range.Upgraded the electronics design of the Refrigerator Incubator Module flown on the Russian MIR Space Station (MIRRIM.) Manned the ‘Wake Ground’ console position in the Payload Operations Control Center (Johnson Space Center) during flight II and III of the Wake Shield satellite.Began employment at Space Industries as a Co-op student while attending Texas A&M.