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At least 1,549 records · Page 86

Engineering microscale systems for fully autonomous intracellular neural interfaces

Conventional electrodes and associated positioning systems for intracellular recording from single neurons in vitro and in vivo are large and bulky, which has largely limited their scalability. Further, acquiring successful intracellular recordings is very tedious, requiring a high degree of skill not readily achieved in a typical laboratory. We report here a robotic, MEMS-based intracellular recording system to overcome the above limitations associated with form-factor, scalability and highly skilled and tedious manual operations required for intracellular recordings. This system combines three distinct technologies: 1) novel microscale, glass-polysilicon penetrating electrode for intracellular recording, 2) electrothermal microactuators for precise microscale movement of each electrode and 3) closed-loop control algorithm for autonomous positioning of electrode inside single neurons. Here, we demonstrate the novel, fully integrated system of glass-polysilicon microelectrode, microscale actuators and controller for autonomous intracellular recordings from single neurons in the abdominal ganglion of Aplysia Californica (n = 5 cells). Consistent resting potentials (< –35 mV) and action potentials (> 60 mV) were recorded after each successful penetration attempt with the controller and microactuated glass-polysilicon microelectrodes. The success rate of penetration and quality of intracellular recordings achieved using electrothermal microactuators were comparable to that of conventional positioning systems. The MEMS-based system offers significant advantages: 1) reduction in overall size for potential use in behaving animals, 2) scalable approach to potentially realize multi-channel recordings and 3) a viable method to fully automate measurement of intracellular recordings. Furthermore, this system will be evaluated in vivo in future rodent studies.

42 ENGINEERING↗

Nuclear Thermal Propulsion (NTP) Development Activities at the NASA Marshall Space Flight Center - 2006 Accomplishments

In 2005-06, the Prometheus program funded a number of tasks at the NASA-Marshall Space Flight Center (MSFC) to support development of a Nuclear Thermal Propulsion (NTP) system for future manned exploration missions. These tasks include the following: 1. NTP Design Develop Test & Evaluate (DDT&E) Planning 2. NTP Mission & Systems Analysis / Stage Concepts & Engine Requirements 3. NTP Engine System Trade Space Analysis and Studies 4. NTP Engine Ground Test Facility Assessment 5. Non-Nuclear Environmental Simulator (NTREES) 6. Non-Nuclear Materials Fabrication & Evaluation 7. Multi-Physics TCA Modeling. This presentation is a overview of these tasks and their accomplishments

Ballard, Richard O.↗

Micro-organ device

A method for fabricating a micro-organ device comprises providing a microscale support having one or more microfluidic channels and one or more micro-chambers for housing a micro-organ and printing a micro-organ on the microscale support using a cell suspension in a syringe controlled by a computer-aided tissue engineering system, wherein the cell suspension comprises cells suspended in a solution containing a material that functions as a three-dimensional scaffold. The printing is performed with the computer-aided tissue engineering system according to a particular pattern. The micro-organ device comprises at least one micro-chamber each housing a micro-organ; and at least one microfluidic channel connected to the micro-chamber, wherein the micro-organ comprises cells arranged in a configuration that includes microscale spacing between portions of the cells to facilitate diffusion exchange between the cells and a medium supplied from the at least one microfluidic channel.

Gonda, Steve R.↗

Micro-Organ Device

A method for fabricating a micro-organ device comprises providing a microscale support having one or more microfluidic channels and one or more micro-chambers for housing a micro-organ and printing a micro-organ on the microscale support using a cell suspension in a syringe controlled by a computer-aided tissue engineering system, wherein the cell suspension comprises cells suspended in a solution containing a material that functions as a three-dimensional scaffold. The printing is performed with the computer-aided tissue engineering system according to a particular pattern. The micro-organ device comprises at least one micro-chamber each housing a micro-organ; and at least one microfluidic channel connected to the micro-chamber, wherein the micro-organ comprises cells arranged in a configuration that includes microscale spacing between portions of the cells to facilitate diffusion exchange between the cells and a medium supplied from the at least one microfluidic channel.

Gonda, Steve R.↗

Vision for Cross-Center MSBE Collaboration on the Gateway Program

Model-Based Systems Engineering (MBSE) can be a challenge when there is only one modeler and one model involved. For the Gateway Program, due to its unique acquisition approach, the modeling efforts involve multiple NASA centers with each developing their own models. Every additional model to be integrated compounds the difficulties, necessitating stronger ontologies and explicitly defined interfaces between models. To help facilitate this integration, a vision of collaboration between centers is in its beginning stages. This vision includes looking at models as systems themselves and developing their own use cases, requirements and interfaces between each of them. The goal of this presentation is to share the Gateway Program's cross-center vision for model collaboration, the lessons learned in developing and implementing that vision for the various system engineering products needed to satisfy life cycle review criteria and how treating models as systems helped in these efforts.

Crane, Jeremiah↗

Gaseous fuel engine and operating strategy for limiting preignition in prechamber sparkplug

Operating a gaseous fuel engine system includes spark-igniting a gaseous hydrogen fuel and air in a prechamber sparkplug to ignite a main charge containing gaseous hydrogen fuel and air in a cylinder. Operating the gaseous fuel engine system also includes determining a preignition condition and conveying cooling air to the prechamber sparkplug based on the preignition condition to limit preignition of gaseous hydrogen fuel and air in the prechamber sparkplug. Related apparatus and control logic is also disclosed.

Singh, Jaswinder↗

Atomization characteristics of swirl injector sprays

Stable combustion within rocket engines is a continuing concern for designers of rocket engine systems. The swirl-coaxial injector has demonstrated effectiveness in achieving atomization and mixing, and therefore stable combustion. Swirl-coaxial injector technology is being deployed in the American RL1OA rocket design and Russian engine systems already make wide spread use of this technology. The present requirement for swirl injector research is derived from NASA's current Reusable Launch Vehicle (RLV) technology program. This report describes some of the background and literature on this topic including drop size measurements, comparison with theoretical predictions, the effect of surface tension on the atomization process, and surface wave characteristics of liquid film at the exit of the injector.

Feikema, Douglas A.↗

A Summary of the NEXT-C Flight Thruster Proto-flight Testing

Aerojet Rocketdyne (AR), under contract to NASA Glenn Research Center, built, tested and delivered the first flight version of the NEXT-C (NASA Evolutionary Xenon Thruster – Commercial) engine system. This system is comprised of a 7 kW thruster and power processing unit which are the commercial variants of the NEXT prototype thruster and power processing unit. In addition to developing the NEXT-C engine system for potential future NASA science missions, AR is dedicated to ensuring that this propulsion system is viable for commercial users and a wider variety of commercial applications. This paper will focus on the performance of the first flight model thruster, SN001, and presents an overview of the proto-flight testing environments and data obtained. For this first flight thruster, the proto-flight test sequence involved characterizing the performance of the thruster, in addition to vibration and thermal vacuum testing of the thruster. Between each of these environmental tests, the performance of the thruster was verified, ensuring that the environmental exposures, i.e. vibration and TVAC, did not affect the thruster performance. Specifically, the proto-flight data obtained included discharge chamber, optics and neutralizer performance. Faraday probe and ExB data obtained in the regions downstream of the thruster are presented and used to calculate thrust, and therefore specific impulse and total efficiency. Lastly, data are presented showing how the centroid of the ion beam, assumed to be indicative of the thrust vector location, varies throughout the entire proto-flight test campaign. The proto-flight testing of the NEXT-C PPU is documented in a previously published paper by Bontempo4. Following the proto-flight testing of the thruster, the thruster and its PPU successfully completed a System Integrated Test (SIT) tailored to the DART Mission. After the completion of the proto-flight testing, the SN001 thruster and SN002 PPU were delivered to APL for use on the DART mission.

Ion thruster↗

Translating Vision into Design: A Method for Conceptual Design Development

One of the most challenging tasks for engineers is the definition of design solutions that will satisfy high-level strategic visions and objectives. Even more challenging is the need to demonstrate how a particular design solution supports the high-level vision. This paper describes a process and set of system engineering tools that have been used at the Johnson Space Center to analyze and decompose high-level objectives for future human missions into design requirements that can be used to develop alternative concepts for vehicles, habitats, and other systems. Analysis and design studies of alternative concepts and approaches are used to develop recommendations for strategic investments in research and technology that support the NASA Integrated Space Plan. In addition to a description of system engineering tools, this paper includes a discussion of collaborative design practices for human exploration mission architecture studies used at the Johnson Space Center.

Carpenter, Joyce E.↗

Risk Reduction on X-33/RLV Engines

Risk management has received considerable attention in the X-33 and Reusable Launch Vehicle (RLV) program due to aggressive schedules, limited funding. and planned private investment to develop the commercial VentureStar vehicle. As an X-33 and RLV team member and main propulsion supplier, Boeing Rocketdyn Propulsion and Power has addressed risk through a methodical application of systems engineering in identifying, assessing, and mitigating risks. The methods employed involve rigorous risk mitigation planning early in development, continuous risk monitoring and assessment during the course of development, and the systematic verification of compliance with technical requirements prior to delivery. In addition, an engine system reliability analysis was conducted to reduce risk. In July 1996, NASA selected Lockheed Martin's "Skunk Works" (LMSW) as the lead contractor for the X-33 and RLV program. The X-33 vehicle is a half-scale pathfinder for the full-scale RLV. The LMSW RLV design is a lifting body shaped vehicle employing linear aerospike engine provided propulsion. The initial X-33 flight is planned for the summer of 2000, and the initial VentureStar flight is planned for between 2005 and 2007.

Crowley, Tim↗

A Data-Driven Solution for Performance Improvement

Marketed as the "Software of the Future," Optimal Engineering Systems P.I. EXPERT(TM) technology offers statistical process control and optimization techniques that are critical to businesses looking to restructure or accelerate operations in order to gain a competitive edge. Kennedy Space Center granted Optimal Engineering Systems the funding and aid necessary to develop a prototype of the process monitoring and improvement software. Completion of this prototype demonstrated that it was possible to integrate traditional statistical quality assurance tools with robust optimization techniques in a user- friendly format that is visually compelling. Using an expert system knowledge base, the software allows the user to determine objectives, capture constraints and out-of-control processes, predict results, and compute optimal process settings.

Source record↗

2024 Nasa Lunabotics University Competition: Site Preparation With Bulk Regolith

Lunabotics provides accredited in-stitutions of higher learning students (vocational-technical, college, university) an opportunity to apply the NASA systems engineering process to design and build a prototype robot. This robot would be capable of performing the proposed operations on the Lunar sur-face in support of future Artemis mission goals. Lunabotics features a systems engineering design challenge to engage students in the next phase of hu-man space exploration supporting the Artemis missions. This two-semester event encourages students to design and build an autonomous or telerobotic robot designed to traverse the simulated Lunar surface and complete the assigned construction tasks. The number of teams accepted into this challenge is not predetermined but is based on the scores and overall quality of the Project Management Plans received and other factors.

Lunabotics↗

Appreciative Methods Applied to the Assessment of Complex Systems

Complex systems have characteristics that challenge traditional systems engineering processes and methods. These characteristics have been defined in various ways. INCOSE has previously identified characteristics of complex systems and potential methods to deal with complexity in system development. The purpose of this paper is to provide definitions and describe distinguishing characteristics of complexity using example systems to illustrate approaches to assessing the extent of complexity. The paper applies Appreciative Inquiry to identify and assess complex system characteristics. The characteristics are used to examine several different examples of systems to illuminate areas of complexity. These examples range from seemingly simple systems to complicated systems to complex systems. Different tiers of complexity are identified as a result of the assessment. The paper also identified and introduces topics on managing complexity and the integrating system perspective that represent new directions for the engineering of complex systems. The Appreciative Inquiry approach provides a method for systems engineering practitioners to more readily identify complexity when they encounter it, and to deal more effectively with this complexity once it has been identified.

Watson, Michael↗

Modeling Off-Nominal Behavior in SysML

Fault Management is an essential part of the system engineering process that is limited in its effectiveness by the ad hoc nature of the applied approaches and methods. Providing a rigorous way to develop and describe off-nominal behavior is a necessary step in the improvement of fault management, and as a result, will enable safe, reliable and available systems even as system complexity increases... The basic concepts described in this paper provide a foundation to build a larger set of necessary concepts and relationships for precise modeling of off-nominal behavior, and a basis for incorporating these ideas into the overall systems engineering process.. The simple FMEA example provided applies the modeling patterns we have developed and illustrates how the information in the model can be used to reason about the system and derive typical fault management artifacts.. A key insight from the FMEA work was the utility of defining failure modes as the "inverse of intent", and deriving this from the behavior models.. Additional work is planned to extend these ideas and capabilities to other types of relevant information and additional products.

Soil Moisture Active-Passive (SMAP) Mission↗

Test methods for image-based information in next-generation manufacturing

Typical control designs in the process systems engineering literature have assumed that the primary sensing methodologies are traditional instruments such as thermocouples. Digitalization is changing the landscape for manufacturing, and data-based sensing modalities (e.g., image-based sensing) are becoming of greater interest for plant control. These considerations require novel test/evaluation solutions. For example, process systems engineering researchers may wish to test image-based sensors in simulation. In this work, we provide preliminary thoughts on how image-based technologies might be evaluated via simulation for process systems.

Henrique Oyama↗

Product Lifecycle Management and the Quest for Sustainable Space Explorations

Product Lifecycle Management (PLM) is an outcome of lean thinking to eliminate waste and increase productivity. PLM is inextricably tied to the systems engineering business philosophy, coupled with a methodology by which personnel, processes and practices, and information technology combine to form an architecture platform for product design, development, manufacturing, operations, and decommissioning. In this model, which is being implemented by the Engineering Directorate at the National Aeronautics and Space Administration's (NASA's) Marshall Space Flight Center, total lifecycle costs are important variables for critical decision-making. With the ultimate goal to deliver quality products that meet or exceed requirements on time and within budget, PLM is a powerful concept to shape everything from engineering trade studies and testing goals, to integrated vehicle operations and retirement scenarios. This paper will demonstrate how the Engineering Directorate is implementing PLM as part of an overall strategy to deliver safe, reliable, and affordable space exploration solutions. It has been 30 years since the United States fielded the Space Shuttle. The next generation space transportation system requires a paradigm shift such that digital tools and knowledge management, which are central elements of PLM, are used consistently to maximum effect. The outcome is a better use of scarce resources, along with more focus on stakeholder and customer requirements, as a new portfolio of enabling tools becomes second nature to the workforce. This paper will use the design and manufacturing processes, which have transitioned to digital-based activities, to show how PLM supports the comprehensive systems engineering and integration function. It also will go through a launch countdown scenario where an anomaly is detected to show how the virtual vehicle created from paperless processes will help solve technical challenges and improve the likelihood of launching on schedule, with less hands-on labor needed for processing and troubleshooting.

Caruso, Pamela W.↗

Ultra Efficient Engine Technology Systems Integration and Environmental Assessment

This study documents the design and analysis of four types of advanced technology commercial transport airplane configurations (small, medium large and very large) with an assumed technology readiness date of 2010. These airplane configurations were used as a platform to evaluate the design concept and installed performance of advanced technology engines being developed under the NASA Ultra Efficient Engine Technology (UEET) program. Upon installation of the UEET engines onto the UEET advanced technology airframes, the small and medium airplanes both achieved an additional 16% increase in fuel efficiency when using GE advanced turbofan engines. The large airplane achieved an 18% increase in fuel efficiency when using the P&W geared fan engine. The very large airplane (i.e. BWB), also using P&W geared fan engines, only achieved an additional 16% that was attributed to a non-optimized airplane/engine combination.

Daggett, David L.↗