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Ott, Melanie N.

Publications and source records attributed to Ott, Melanie N..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2020

Space Flight LiDARs, Navigation & Science Instrument Implementations: Lasers, Optoelectronics, Integrated Photonics, Fiber Optic Subsystems and Components

For the past 25 years, the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center's Photonics Group in the Engineering Directorate has been substantially contributing to the flight design, development, production, testing and integration of many science and navigational instruments. The Moon to Mars initiative will rely heavily upon utilizing commercial technologies for instrumentation with aggressive schedule deadlines. The group has an extensive background in screening, qualifying, development and integration of commercial components for spaceflight applications. By remaining adaptable and employing a rigorous approach to component and instrument development, they have forged and fostered relationships with industry partners. They have been willing to communicate lessons learned in packaging, part construction, materials selection, testing, and other facets of the design and production process critical to implementation for high-reliability systems. As a result, this successful collaboration with industry vendors and component suppliers has enabled a history of mission success from the Moon to Mars (and beyond) while balancing cost, schedule, and risk postures. In cases where no commercial components exist, the group works closely with other teams at Goddard Space Flight Center and other NASA field centers to fabricate and produce flight hardware for science, remote sensing, and navigation applications. Summarized here is the last ten years of instrumentation development lessons learned and data collected from the subsystems down to the optoelectronic component level.

Detectors↗
NASA NTRS2019

Optical System Design and Integration of the Global Ecosystem Dynamics Investigation Lidar

The Global Ecosystem Dynamics Investigation (GEDI) instrument was designed, built, and tested in-house at NASA’s Goddard Space Flight Center and launched to the International Space Station (ISS) on December 5, 2018. GEDI is a multi-beam waveform LiDAR (light detection and ranging) designed to measure the Earth’s global tree height and canopy density using 8 laser beam ground tracks separated by roughly 600 meters. Given the ground coverage required and the 2 year mission duration, a unique optical design solution was developed. GEDI generates 8 ground sampling tracks from 3 transmitter systems viewed by a single receiver telescope, all while maximizing system optical efficiency and transmitter to receiver boresight alignment margin. The GEDI optical design, key optical components, and system level integration and testing are presented here. GEDI began 2 years of science operations in March 2019 and so far, it is meeting all of its key optical performance requirements and is returning outstanding science.

Integration↗
NASA NTRS2019

Space Flight Optoelectronics and Photonics Qualification

The Photonics group top level processes regarding development and qualification of space flight hardware for optoelectronic components along with our contributions and successes with LIDAR systems, space flight reliability heritage, and our testing capabilities are conveyed with this power point presentation.

Optical Systems↗
NASA NTRS2018

System to Perform Radio Frequency Interferometry Using Optical Fiber Sensing Signal Processing Techniques

Aspects of the present disclosure involve a system and method for performing radio frequency interferometry using optical fiber sensing. Optical fiber sensing is performed as a reference signal is defined and compared, in the optical domain, to incoming signals to obtain interference fringe patterns that can be used to decode phase shift offsets with respect to the designated reference signal. The phase shift offsets can be determined by first optically modulating the reference and incoming signals using a laser source as the carrier. In the optical domain, the reference and incoming signals are combined using an optical coupler and then converted back to the electrical domain for processing.

Ott, Melanie N.↗
NASA NTRS2016

Cryogenic Fiber Optic Assemblies for Spaceflight Environments: Design, Manufacturing, Testing, and Integration

Fiber optic assemblies have been used on spaceflight missions for many years as an enabling technology for routing, transmitting, and detecting optical signals. Due to the overwhelming success of NASA in implementing fiber optic assemblies on spaceflight science-based instruments, system scientists increasingly request fibers that perform in extreme environments while still maintaining very high optical transmission, stability, and reliability. Many new applications require fiber optic assemblies that will operate down to cryogenic temperatures as low as 20 Kelvin. In order for the fiber assemblies to operate with little loss in optical throughput at these extreme temperatures requires a system level approach all the way from how the fiber assembly is manufactured to how it is held, routed, and integrated. The NASA Goddard Code 562 Photonics Group has been designing, manufacturing, testing, and integrating fiber optics for spaceflight and other high reliability applications for nearly 20 years. Design techniques and lessons learned over the years are consistently applied to developing new fiber optic assemblies that meet these demanding environments. System level trades, fiber assembly design methods, manufacturing, testing, and integration will be discussed. Specific recent examples of ground support equipment for the James Webb Space Telescope (JWST); the Ice, Cloud and Land Elevation Satellite-2 (ICESat-2); and others will be included.

Fiber Optic↗
NASA NTRS2010

Space Flight Applications of Optical Fiber; 30 Years of Space Flight Success

For over thirty years NASA has had success with space flight missions that utilize optical fiber component technology. One of the early environmental characterization experiments that included optical fiber was launched as the Long Duration Exposure Facility in 1978. Since then, multiple missions have launched with optical fiber components that functioned as expected, without failure throughout the mission life. The use of optical fiber in NASA space flight communications links and exploration and science instrumentation is reviewed.

Ott, Melanie N.↗
NASA NTRS2010

Implementation and Qualifications Lessons Learned for Space Flight Photonic Components

This slide presentation reviews the process for implementation and qualification of space flight photonic components. It discusses the causes for most common anomalies for the space flight components, design compatibility, a specific failure analysis of optical fiber that occurred in a cable in 1999-2000, and another ExPCA connector anomaly involving pins that broke off. It reviews issues around material selection, quality processes and documentation, and current projects that the Photonics group is involved in. The importance of good documentation is stressed.

Ott, Melanie N.↗
NASA NTRS2009

The Fiber Optic Subsystem Components on Express Logistics Carrier for International Space Station

ISS SSP 50184 HRDL optical fiber communication subsystem, has system level requirements that were changed to accommodate large loss optical fiber links previously installed. SSQ22680 design is difficult to implement, no metal shell over socket/pin combination to protect the weak part of the pin. Additions to ISS are planned for the future. AVIM still used for interconnection in space flight applications without incident. Thermal cycling resulted in less than 0.25 dB max change in Insertion Loss for all types during cycling, nominal as compared to the AVIM. Vibration testing results conclusion; no significant changes, nominal as compared to AVIM.

Ott, Melanie N.↗
NASA NTRS2009

Optical Fiber Assemblies for Space Flight from the NASA Goddard Space Flight Center, Photonics Group

The Photonics Group at NASA Goddard Space Flight Center in the Electrical Engineering Division of the Advanced Engineering and Technologies Directorate has been involved in the design, development, characterization, qualification, manufacturing, integration and anomaly analysis of optical fiber subsystems for over a decade. The group supports a variety of instrumentation across NASA and outside entities that build flight systems. Among the projects currently supported are: The Lunar Reconnaissance Orbiter, the Mars Science Laboratory, the James Webb Space Telescope, the Express Logistics Carrier for the International Space Station and the NASA Electronic Parts. and Packaging Program. A collection of the most pertinent information gathered during project support over the past year in regards to space flight performance of optical fiber components is presented here. The objective is to provide guidance for future space flight designs of instrumentation and communication systems.

Ott, Melanie N.↗
NASA NTRS2008

The Optical Fiber Array Bundle Assemblies for the NASA Lunar Reconnaissance Orbiter

The United States, National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC), Fiber Optics Team in the Electrical Engineering Division of the Applied Engineering and Technology Directorate, designed, developed and integrated the space flight optical fiber array hardware assemblies for the Lunar Reconnaissance Orbiter (LRO). The two new assemblies that were designed and manufactured at NASA GSFC for the LRO exist in configurations that are unique in the world for the application of ranging and lidar. These assemblies were developed in coordination with Diamond Switzerland, and the NASA GSFC Mechanical Systems Division. The assemblies represent a strategic enhancement for NASA's Laser Ranging and Laser Radar (LIDAR) instrument hardware by allowing light to be moved to alternative locations that were not feasible in past space flight implementations. An account will be described of the journey and the lessons learned from design to integration for the Lunar Orbiter Laser Altimeter and the Laser Ranging Application on the LRO. The LRO is scheduled to launch end of 2008.

Ott, Melanie N.↗
NASA NTRS2008

Failure Analysis Study and Long-Term Reliability of Optical Assemblies with End-Face Damage

In June 2005, the NESC received a multi-faceted request to determine the long term reliability of fiber optic termini on the ISS that exhibited flaws not manufactured to best workmanship practices. There was a lack of data related to fiber optic workmanship as it affects the long term reliability of optical fiber assemblies in a harsh environment. A fiber optic defect analysis was requested which would find and/or create various types of chips, spalls, scratches, etc., that were identified by the ISS personnel. Once the defects and causes were identified the next step would be to perform long term reliability testing of similar assemblies with similar defects. The goal of the defect analysis would be for the defects to be observed and documented for deterioration of fiber optic performance. Though this report mostly discusses what has been determined as evidence of poor manufacturing processes, it also concludes the majority of the damage could have been avoided with a rigorous process in place.

Kichak, Robert A.↗
NASA NTRS2008

Development, Qualification and Integration of the Optical Fiber Array Assemblies for the Lunar Reconnaissance Orbiter

The NASA Goddard Fiber Optics Team in the Electrical Engineering Division of the Applied Engineering and Technology Directorate, designed, developed and integrated the space flight optical fiber array hardware for the Lunar Reconnaissance Orbiter (LRO). The two new assemblies that were designed and manufacturing at GSFC for the LRO exist in configurations that are unique in the world for the application of ranging and LIDAR. Described here is an account of the journey and the lessons learned from design to integration for the Lunar Orbiter Laser Altimeter and the Laser Ranging Application on the LRO.

Ott, Melanie N.↗
NASA NTRS2008

Applications of Optical Fiber Assemblies in Harsh Environments, the Journey Past, Present and Future

Over the past ten years, NASA has studied the effects of harsh environments on optical fiber assemblies for communication systems, lidar systems, and science missions. The culmination of this has resulted in recent technologies that are unique and tailored to meeting difficult requirements under challenging performance constraints. This presentation will focus on the past mission applications of optical fiber assemblies including; qualification information, lessons learned and new technological advances that will enable the road ahead.

Ott, Melanie N.↗
NASA NTRS2008

Fiber Optic Cable Thermal Preparation to Ensure Stable Operation

Fiber optic cables are widely used in modern systems that must provide stable operation during exposure to changing environmental conditions. For example, a fiber optic cable on a satellite may have to reliably function over a temperature range of -50 C up to 125 C. While the system requirements for a particular application will dictate the exact method by which the fibers should be prepared, this work will examine multiple ruggedized fibers prepared in different fashions and subjected to thermal qualification testing. The data show that if properly conditioned the fiber cables can provide stable operation, but if done incorrectly, they will have large fluctuations in transmission.

Thoames Jr, William J.↗
NASA NTRS2008

Vibration Performance Comparison Study on Current Fiber Optic Connector Technologies

Fiber optic cables are increasingly being used in harsh environments where they are subjected to vibration. Understanding the degradation in performance under these conditions is essential for integration of the fibers into the given application. System constraints oftentimes require fiber optic connectors so subsystems can be removed or assembled as needed. In the present work, various types of fiber optic connectors were monitored in-situ during vibration testing to examine the transient change in optical transmission and the steady-state variation following the event. Inspection of the fiber endfaces and connectors was performed at chosen intervals throughout the testing.

Ott, Melanie N.↗
NASA NTRS2007

Space Flight Requirements for Fiber Optic Components; Qualification Testing and Lessons Learned

"Qualification" of fiber optic components holds a very different meaning than it did ten years ago. In the past, qualification meant extensive prolonged testing and screening that led to a programmatic method of reliability assurance. For space flight programs today, the combination of using higher performance commercial technology, with shorter development schedules and tighter mission budgets makes long term testing and reliability characterization unfeasible. In many cases space flight missions will be using technology within years of its development and an example of this is fiber laser technology. Although the technology itself is not a new product the components that comprise a fiber laser system change frequently as processes and packaging changes occur. Once a process or the materials for manufacturing a component change, even the data that existed on its predecessor can no longer provide assurance on the newer version. In order to assure reliability during a space flight mission, the component engineer must understand the requirements of the space flight environment as well as the physics of failure of the components themselves. This can be incorporated into an efficient and effective testing plan that "qualifies" a component to specific criteria defined by the program given the mission requirements and the component limitations. This requires interaction at the very initial stages of design between the system design engineer, mechanical engineer, subsystem engineer and the component hardware engineer. Although this is the desired interaction what typically occurs is that the subsystem engineer asks the components or development engineers to meet difficult requirements without knowledge of the current industry situation or the lack of qualification data. This is then passed on to the vendor who can provide little help with such a harsh set of requirements due to high cost of testing for space flight environments. This presentation is designed to guide the engineers of design, development and components, and vendors of commercial components with how to make an efficient and effective qualification test plan with some basic generic information about many space flight requirements. Issues related to the ~ physics of failure, acceptance criteria and lessons learned will also be discussed to assist with understanding how to approach a space flight mission in an ever changing commercial photonics industry.

Ott, Melanie N.↗