Printable Spacecraft: Flexible Electronic Platforms for NASA Missions

Why printed electronics? Why should NASA use printed electronics to make a spacecraft? Three words provide the answer: universal, impactful, progressive. The technology is universal because the applications it can affect are broad and diverse from simple sensors to fully functional spacecraft. The impact of flexible, printed electronics range from straightforward mass, volume and cost savings all the way to enabling new mission concepts. The benefits of the technology will become progressively larger from what is achievable today so that investments will pay dividends tomorrow, next year and next decade. We started off three years ago asking the question can you build an entire spacecraft out of printed electronics? In other words, can you design and fabricate a fully integrated, electronic system that performs the same end-to-end functions of a spacecraft - take scientific measurements, perform data processing, provide data storage, transmit the data, powers itself, orients and propels itself - all out of thin flexible sheets of printed electronics? This "Printable Spacecraft" pushes the limits of printed flexible electronics performance. So the answer is yes, more or less. In our studies for the NIAC (NASA Innovative Advanced Concepts) program, we have explored this question further, to explain more completely what "more or less" means and to outline what is needed to make the answer a definitive "yes". Despite its appealing "Flat Stanley"-like (a book series by Jeff Brown) qualities, making a Printable Spacecraft is not as easy as flattening the Cassini spacecraft with a bulletin board, as was Stanley Lamchop's fate. But, if NASA invests in the design challenges, the materials challenges, the performance challenges of printed electronics, it might find itself with a spacecraft that can enable as many adventures and advantages as Flat Stanley including putting it in an envelope and mailing it to the planet of your choice. You just have to let your imagination take over. In this report we document the work of the Phase 2 Printable Spacecraft task conducted under the guidance and leadership of the NIAC program. In Phase One of the NIAC task entitled "Printable Spacecraft", we investigated the viability of printed electronics technologies for creating multi-functional spacecraft platforms. Mission concepts and architectures that could be enhanced or enabled with this technology were explored. In Phase 2 we tried to answer the more practical questions such as can you really build a multi-functional printed electronic spacecraft system? If you do, can it survive the space environment? Even if it can, what benefit does a printable system provide over a traditional implementation of a spacecraft

Printable Spacecraft: Flexible Electronic Platforms for NASA Missions

Atmospheric confetti. Inchworm crawlers. Blankets of ground penetrating radar. These are some of the unique mission concepts which could be enabled by a printable spacecraft. Printed electronics technology offers enormous potential to transform the way NASA builds spacecraft. A printed spacecraft's low mass, volume and cost offer dramatic potential impacts to many missions. Network missions could increase from a few discrete measurements to tens of thousands of platforms improving areal density and system reliability. Printed platforms could be added to any prime mission as a low-cost, minimum resource secondary payload to augment the science return. For a small fraction of the mass and cost of a traditional lander, a Europa flagship mission might carry experimental printed surface platforms. An Enceladus Explorer could carry feather-light printed platforms to release into volcanic plumes to measure composition and impact energies. The ability to print circuits directly onto a variety of surfaces, opens the possibility of multi-functional structures and membranes such as "smart" solar sails and balloons. The inherent flexibility of a printed platform allows for in-situ re-configurability for aerodynamic control or mobility. Engineering telemetry of wheel/soil interactions are possible with a conformal printed sensor tape fit around a rover wheel. Environmental time history within a sample return canister could be recorded with a printed sensor array that fits flush to the interior of the canister. Phase One of the NIAC task entitled "Printable Spacecraft" investigated the viability of printed electronics technologies for creating multi-functional spacecraft platforms. Mission concepts and architectures that could be enhanced or enabled with this technology were explored. This final report captures the results and conclusions of the Phase One study. First, the report presents the approach taken in conducting the study and a mapping of results against the proposed Phase One objectives. Then an overview of the general field of printed electronics is provided, including manufacturing approaches, commercial drivers, and the current state of integrated systems. The bulk of the report contains the results and findings of Phase One organized into four sections: a survey of components required for a printable spacecraft, technology roadmaps considerations, science mission and engineering applications, and potential risks and challenges of the technology

Land grant for 160 acres in Lima, Ohio, signed by President Martin Van Buren, 1837.

David Thatcher, of Montgomery County, Ohio is granted 160 acres in Lima, Ohio. Signed by President Van Buren, 21 August 1837. On parchment, with Seal of the General Land Office adhered.https://digitalcommons.wofford.edu/littlejohnmss/1222/thumbnail.jp

Propulsive performance of oscillating plates with time-periodic flexibility

We use small-amplitude inviscid theory to study the swimming performance of a flexible flapping plate with time-varying flexibility. The stiffness of the plate oscillates at twice the frequency of the kinematics in order to maintain a symmetric motion. Plates with constant and time-periodic stiffness are compared over a range of mean plate stiffness, oscillating stiffness amplitude, and oscillating stiffness phase for isolated heaving, isolated pitching, and combined leading edge kinematics. We find that there is a profound impact of oscillating stiffness on the thrust, with a lesser impact on propulsive efficiency. Thrust improvements of up to 35% relative to a constant-stiffness plate are observed. For large enough frequencies and amplitudes of the stiffness oscillation, instabilities emerge. The unstable regions may confer enhanced propulsive performance; this hypothesis must be verified via experiments or nonlinear simulations.Comment: 31 pages, 12 figure

An IR Search for Extinguished Supernovae in Starburst Galaxies

IR and Radio band observations of heavily extinguished regions in starburst galaxies suggest a very high SN rate associated with such regions. Optically measured supernova (SN) rates may therefore underestimate the total SN rate by factors of up to 10, due to the high extinction to SNe in starburst regions. The IR/radio SN rates come from a variety of indirect means, however, which suffer from model dependence and other problems. We describe a direct measurement of the SN rate from a regular patrol of starburst galaxies done with K' band imaging to minimize the effects of extinction. A collection of K' measurements of core-collapse SNe near maximum light is presented. Results of a preliminary SN search using the MIRC camera at the Wyoming IR Observatory (WIRO), and an improved search using the ORCA optics are described. A monthly patrol of starburst galaxies within 25 Mpc should yield 1.6 - 9.6 SNe/year. Our MIRC search with low-resolution (2.2" pixels) failed to find extinguished SNe, limiting the SN rate outside the nucleus (at > 15" radius) to less than 3.8 Supernova Rate Units (SRU or SNe/century/10^10 L(solar); 90% confidence). The MIRC camera had insufficient resolution to search nuclear starburst regions, where SN activity is concentrated, explaining why we found no heavily obscured SNe. We conclude that high-resolution, small field SN searches in starburst nuclei are more productive than low resolution, large-field searches, even for our large galaxies. With our ORCA high-resolution optics, we could limit the total SN rate to < 1.3 SRU at 90% confidence in 3 years of observations, lower than the most pessimistic estimate.Comment: AJ Submitted 1998 Dec. 13. View figures and download all as one file at http://panisse.lbl.gov/public/bruce/irs

The association of kidney function and cognitive decline in older patients at risk of cardiovascular disease: a longitudinal data analysis

Background: Chronic kidney disease (CKD) has been identified as a significant direct marker for cognitive decline, but controversy exists regarding the magnitude of the association of kidney function with cognitive decline across the different CKD stages. Therefore, the aim of this study was to investigate the association of kidney function with cognitive decline in older patients at high risk of cardiovascular disease, using data from the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER). Methods Data of 5796 patients of PROSPER were used. Strata were made according to clinical stages of CKD based on estimated glomerular filtration rate; &lt; 30 ml/min/1.73m2 (stage 4), 30-45 ml/min/1.73m2 (stage 3b), 45-60 ml/min/1.73m2 (stage 3a) and ≥ 60 ml/min/1.73m2 (stage 1–2). Cognitive function and functional status was assessed at six different time points and means were compared at baseline and over time, adjusted for multiple prespecified variables. Stratified analyses for history of vascular disease were executed. Results: Mean age was 75.3 years and 48.3% participants were male. Mean follow-up was 3.2 years. For all cognitive function tests CKD stage 4 compared to the other stages had the worst outcome at baseline and a trend for faster cognitive decline over time. When comparing stage 4 versus stage 1–2 over time the estimates (95% CI) were 2.23 (0.60–3.85; p = 0.009) for the Stroop-Colour-Word test, − 0.33 (− 0.66–0.001; p = 0.051) for the Letter-Digit-Coding test, 0.08 (− 0.06–0.21; p = 0.275) for the Picture-Word-Learning test with immediate recall and − 0.07 (− 0.02–0.05; p = 0.509) for delayed recall. This association was most present in patients with a history of vascular disease. No differences were found in functional status. Conclusion: In older people with vascular burden, only severe kidney disease (CKD stage 4), but not mild to modest kidney disease (CKD stage 3a and b), seem to be associated with cognitive impairment at baseline and cognitive decline over time. The association of severe kidney failure with cognitive impairment and decline over time was more outspoken in patients with a history of vascular disease, possibly due to a higher probability of polyvascular damage, in both kidney and brain, in patients with proven cardiovascular disease

Effect of Oral Iron Repletion on Exercise Capacity in Patients With Heart Failure With Reduced Ejection Fraction and Iron Deficiency: The IRONOUT HF Randomized Clinical Trial.

Importance: Iron deficiency is present in approximately 50% of patients with heart failure with reduced left ventricular ejection fraction (HFrEF) and is an independent predictor of reduced functional capacity and mortality. However, the efficacy of inexpensive readily available oral iron supplementation in heart failure is unknown. Objective: To test whether therapy with oral iron improves peak exercise capacity in patients with HFrEF and iron deficiency. Design, Setting, and Participants: Phase 2, double-blind, placebo-controlled randomized clinical trial of patients with HFrEF ( Interventions: Oral iron polysaccharide (n = 111) or placebo (n = 114), 150 mg twice daily for 16 weeks. Main Outcomes and Measures: The primary end point was a change in peak oxygen uptake (V̇o2) from baseline to 16 weeks. Secondary end points were change in 6-minute walk distance, plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels, and health status as assessed by Kansas City Cardiomyopathy Questionnaire (KCCQ, range 0-100, higher scores reflect better quality of life). Results: Among 225 randomized participants (median age, 63 years; 36% women) 203 completed the study. The median baseline peak V̇o2 was 1196 mL/min (interquartile range [IQR], 887-1448 mL/min) in the oral iron group and 1167 mL/min (IQR, 887-1449 mL/min) in the placebo group. The primary end point, change in peak V̇o2 at 16 weeks, did not significantly differ between the oral iron and placebo groups (+23 mL/min vs -2 mL/min; difference, 21 mL/min [95% CI, -34 to +76 mL/min]; P = .46). Similarly, at 16 weeks, there were no significant differences between treatment groups in changes in 6-minute walk distance (-13 m; 95% CI, -32 to 6 m), NT-proBNP levels (159; 95% CI, -280 to 599 pg/mL), or KCCQ score (1; 95% CI, -2.4 to 4.4), all P \u3e .05. Conclusions and Relevance: Among participants with HFrEF with iron deficiency, high-dose oral iron did not improve exercise capacity over 16 weeks. These results do not support use of oral iron supplementation in patients with HFrEF. Trial Registration: clinicaltrials.gov Identifier: NCT02188784

Health-related quality of life and symptom burden in patients on haemodialysis

BACKGROUND: Patients on haemodialysis generally experience poor health-related quality of life (HRQoL) and a broad range of physical and mental symptoms, but it is unknown whether this differs between younger and older patients. We aimed to describe the trajectories of HRQoL and symptom burden of patients &lt; 70 and ≥ 70 years old, and to assess the impact of symptom burden on HRQoL.METHODS: In incident Dutch haemodialysis patients, HRQoL and symptoms were measured with the 12-item Short Form Health Survey and Dialysis Symptom Index. We used linear mixed models for examining the trajectories of HRQoL and symptom burden during the first year of dialysis, and linear regression for the impact of symptom burden on HRQoL.RESULTS: In 774 patients, the trajectories of physical HRQoL, mental HRQoL, and symptom burden were stable during the first year of dialysis. Compared with patients aged &lt; 70 years, patients ≥ 70 years reported similar physical HRQoL (mean difference -0.61, 95% CI -1.86; 0.63), better mental HRQoL (1.77, 95% CI 0.54; 3.01), and lower symptom burden (-2.38, 95% CI -5.08; 0.32). With increasing symptom burden, physical HRQoL declined more in older than in younger patients (β -0.287 versus -0.189, respectively, p-value for interaction = 0.007). For mental HRQoL, this decrease was similar in both age groups (β -0.295 versus -0.288, P = 0.847).CONCLUSIONS: Older haemodialysis patients generally experience a better mental HRQoL and a (non-statistically significant) lower symptom burden, compared to younger patients. Their physical HRQoL declines more rapidly with increasing symptom burden.</p