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Philip H Stahl - One of the best experts on this subject based on the ideXlab platform.
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optics technology for large aperture Space Telescopes from fabrication to final acceptance tests
Advances in Optics and Photonics, 2018Co-Authors: Isaac Trumper, Philip H Stahl, Pascal Hallibert, Jonathan W Arenberg, Hideyo Kunieda, Olivier Guyon, Dae Wook KimAbstract:This review paper addresses topics of fabrication, testing, alignment, and as-built performance of reflective Space optics for the next generation of Telescopes across the x-ray to far-infrared spectrum. The technology presented in the manuscript represents the most promising methods to enable a next level of astronomical observation capabilities for Space-based Telescopes as motivated by the science community. While the technology to produce the proposed Telescopes does not exist in its final form, the optics industry is making steady and impressive progress toward these goals across all disciplines. We hope that through sharing these developments in context of the science objectives, further connections and improvements are enabled to push the envelope of the technology.
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multivariable parametric cost model for Space and ground Telescopes
Proceedings of SPIE, 2016Co-Authors: Philip H Stahl, Todd HenrichsAbstract:Parametric cost models can be used by designers and project managers to perform relative cost comparisons between major architectural cost drivers and allow high-level design trades; enable cost-benefit analysis for technology development investment; and, provide a basis for estimating total project cost between related concepts. This paper hypothesizes a single model, based on published models and engineering intuition, for both ground and Space Telescopes: OTA Cost ~ (X) D (1.75 ± 0.05) λ (-0.5 ± 0.25) T -0.25 e (-0.04) Y Specific findings include: Space Telescopes cost 50X to 100X more ground Telescopes; diameter is the most important CER; cost is reduced by approximately 50% every 20 years (presumably because of technology advance and process improvements); and, for Space Telescopes, cost associated with wavelength performance is balanced by cost associated with operating temperature. Finally, duplication only reduces cost for the manufacture of identical systems (i.e. multiple aperture sparse arrays or interferometers). And, while duplication does reduce the cost of manufacturing the mirrors of segmented primary mirror, this cost savings does not appear to manifest itself in the final primary mirror assembly (presumably because the structure for a segmented mirror is more complicated than for a monolithic mirror).
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engineering specifications for large aperture uvo Space Telescopes derived from science requirements
Proceedings of SPIE, 2013Co-Authors: Philip H Stahl, M Postman, Scott W SmithAbstract:The Advance Mirror Technology Development (AMTD) project is a three year effort initiated in FY12 to mature by at least a half TRL step six critical technologies required to enable 4 to 8 meter UVOIR Space telescope primary mirror assemblies for both general astrophysics and ultra-high contrast observations of exoplanets. AMTD uses a sciencedriven systems engineering approach. We mature technologies required to enable the highest priority science AND result in a high-performance low-cost low-risk system. To provide the science community with options, we are pursuing multiple technology paths. We have assembled an outstanding team from academia, industry, and government with extensive expertise in astrophysics and exoplanet characterization, and in the design/manufacture of monolithic and segmented Space Telescopes. A key accomplishment is deriving engineering specifications for advanced normalincidence monolithic and segmented mirror systems needed to enable both general astrophysics and ultra-high contrast observations of exoplanets missions as a function of potential launch vehicles and their mass and volume constraints.
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overview and recent accomplishments of the advanced mirror technology development amtd for large aperture uvoir Space Telescopes project
Proceedings of SPIE, 2013Co-Authors: Philip H Stahl, M Postman, Laura Abplanalp, William H Arnold, Ron Eng, Anand SivaramakrishnanAbstract:The Advance Mirror Technology Development (AMTD) project is a three year effort initiated in FY12 to mature by at least a half TRL step six critical technologies required to enable 4 to 8 meter UVOIR Space telescope primary mirror assemblies for both general astrophysics and ultra-high contrast observations of exoplanets. Thus far, AMTD has achieved all of its goals and accomplished all of its milestones. We did this by assembling an outstanding team from academia, industry, and government with extensive expertise in astrophysics and exoplanet characterization, and in the design/manufacture of monolithic and segmented Space Telescopes; by deriving engineering specifications for advanced normal-incidence mirror systems needed to make the required science measurements; and by defining and prioritizing the most important technical problems to be solved.
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update to single variable parametric cost models for Space Telescopes
Optical Engineering, 2013Co-Authors: Philip H Stahl, Todd Henrichs, Alexander R. Luedtke, Miranda WestAbstract:Parametric cost models are an important tool routinely used to plan missions, compare concepts, and justify technology investments. In 2010, the article, “Single-variable parametric cost models for Space Telescopes,” was published [H. P. Stahl et al., Opt. Eng. 49(7), 073006 (2010)]. That paper presented new single-variable cost models for Space telescope optical telescope assembly. These models were created by applying standard statistical methods to data collected from 30 different Space telescope missions. The results were compared with previously published models. A postpublication independent review of that paper’s database identified several inconsistencies. To correct these inconsistencies, a two-year effort was undertaken to reconcile our database with source documents. This paper updates and revises the findings of our 2010 paper. As a result of the review, some Telescopes’ data were removed, some were revised, and data for a few new Telescopes were added to the database. As a consequence, there have been changes to the 2010 published results. But our two most important findings remain unchanged: aperture diameter is the primary cost driver for large Space Telescopes, and it costs more per kilogram to build a low-areal-density low-stiffness telescope than a more massive high-stiffness telescope. One significant difference is that we now report telescope cost to vary linearly from 5% to 30% of total mission cost, instead of the previously reported average of 20%. To fully understand the content of this update, the authors recommend that one also read the 2010 paper.
Ulrich Wittrock - One of the best experts on this subject based on the ideXlab platform.
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unimorph deformable mirror for Space Telescopes environmental testing
Optics Express, 2016Co-Authors: Peter Rausch, Sven Verpoort, Ulrich WittrockAbstract:We have developed and manufactured a unimorph deformable mirror for Space Telescopes based on piezoelectric actuation. The mirror features 44 actuators, has an aperture of 50 mm, and is designed to reproduce low-order Zernike modes with a stroke of several tens of μm. We assessed the Space compliance by operating the mirror in thermal vacuum, and exposing it to random and sinusoidal vibrations, as well as to ionizing irradiation. Additionally, the operational life time and the laser power handling capability were tested. The mirror was successfully operated in thermal vacuum at 100 K. We report on the conducted tests and the methods used to evaluate the mirror’s performance, and discuss the compliance with the demanded requirements.
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unimorph deformable mirror for Space Telescopes design and manufacturing
Optics Express, 2015Co-Authors: Peter Rausch, Sven Verpoort, Ulrich WittrockAbstract:Large Space Telescopes made of deployable and lightweight structures suffer from aberrations caused by thermal deformations, gravitational release, and alignment errors which occur during the deployment procedure. An active optics system would allow on-site correction of wave-front errors, and ease the requirements on thermal and mechanical stability of the optical train. In the course of a project funded by the European Space Agency we have developed and manufactured a unimorph deformable mirror based on piezoelectric actuation. The mirror is able to work in Space environment and is designed to correct for large aberrations of low order with high surface fidelity. This paper discusses design, manufacturing and performance results of the deformable mirror.
Todd Henrichs - One of the best experts on this subject based on the ideXlab platform.
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multivariable parametric cost model for Space and ground Telescopes
Proceedings of SPIE, 2016Co-Authors: Philip H Stahl, Todd HenrichsAbstract:Parametric cost models can be used by designers and project managers to perform relative cost comparisons between major architectural cost drivers and allow high-level design trades; enable cost-benefit analysis for technology development investment; and, provide a basis for estimating total project cost between related concepts. This paper hypothesizes a single model, based on published models and engineering intuition, for both ground and Space Telescopes: OTA Cost ~ (X) D (1.75 ± 0.05) λ (-0.5 ± 0.25) T -0.25 e (-0.04) Y Specific findings include: Space Telescopes cost 50X to 100X more ground Telescopes; diameter is the most important CER; cost is reduced by approximately 50% every 20 years (presumably because of technology advance and process improvements); and, for Space Telescopes, cost associated with wavelength performance is balanced by cost associated with operating temperature. Finally, duplication only reduces cost for the manufacture of identical systems (i.e. multiple aperture sparse arrays or interferometers). And, while duplication does reduce the cost of manufacturing the mirrors of segmented primary mirror, this cost savings does not appear to manifest itself in the final primary mirror assembly (presumably because the structure for a segmented mirror is more complicated than for a monolithic mirror).
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update to single variable parametric cost models for Space Telescopes
Optical Engineering, 2013Co-Authors: Philip H Stahl, Todd Henrichs, Alexander R. Luedtke, Miranda WestAbstract:Parametric cost models are an important tool routinely used to plan missions, compare concepts, and justify technology investments. In 2010, the article, “Single-variable parametric cost models for Space Telescopes,” was published [H. P. Stahl et al., Opt. Eng. 49(7), 073006 (2010)]. That paper presented new single-variable cost models for Space telescope optical telescope assembly. These models were created by applying standard statistical methods to data collected from 30 different Space telescope missions. The results were compared with previously published models. A postpublication independent review of that paper’s database identified several inconsistencies. To correct these inconsistencies, a two-year effort was undertaken to reconcile our database with source documents. This paper updates and revises the findings of our 2010 paper. As a result of the review, some Telescopes’ data were removed, some were revised, and data for a few new Telescopes were added to the database. As a consequence, there have been changes to the 2010 published results. But our two most important findings remain unchanged: aperture diameter is the primary cost driver for large Space Telescopes, and it costs more per kilogram to build a low-areal-density low-stiffness telescope than a more massive high-stiffness telescope. One significant difference is that we now report telescope cost to vary linearly from 5% to 30% of total mission cost, instead of the previously reported average of 20%. To fully understand the content of this update, the authors recommend that one also read the 2010 paper.
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Parametric Cost Models for Space Telescopes
2013Co-Authors: H. Philip Stahl, Todd Henrichs, Courtnay DollingerAbstract:Multivariable parametric cost models for Space Telescopes provide several benefits to designers and Space system project managers. They identify major architectural cost drivers and allow high-level design trades. They enable cost-benefit analysis for technology development investment. And, they provide a basis for estimating total project cost. A survey of historical models found that there is no definitive Space telescope cost model. In fact, published models vary greatly [1]. Thus, there is a need for parametric Space Telescopes cost models. An effort is underway to develop single variable [2] and multi-variable [3] parametric Space telescope cost models based on the latest available data and applying rigorous analytical techniques. Specific cost estimating relationships (CERs) have been developed which show that aperture diameter is the primary cost driver for large Space Telescopes; technology development as a function of time reduces cost at the rate of 50p per 17 years; it costs less per square meter of collecting aperture to build a large telescope than a small telescope; and increasing mass reduces cost.
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update on parametric cost models for Space Telescopes
Proceedings of SPIE, 2011Co-Authors: Philip H Stahl, Todd Henrichs, Alexander R. Luedtke, Miranda WestAbstract:Parametric cost models are used to plan missions, compare concepts and justify technology investments. This paper updates an ongoing effort to develop cost modes for Space Telescopes and summarizes how recent database changes have changed previously published preliminary results. While the models are evolving, the previously published findings are valid: telescope cost increases with aperture diameter; it costs less per square meter of collecting aperture to build a large telescope than a small telescope; lower areal density Telescopes cost more than more massive Telescopes.
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Update on parametric cost models for Space Telescopes
2011Co-Authors: H. Philip Stahl, Todd Henrichs, Alexander R. Luedtke, Miranda WestAbstract:ABSTRACT Parametric cost models are used to plan missions, compare concepts and justify technology investments. This paper updates an on-going effort to develop cost modes for Space Telescopes and summarizes how recent database changes have changed previously published preliminary results. While the models are evolving, the previously published findings are valid: telescope cost increases with aperture diameter; it costs less per square meter of collecting aperture to build a large telescope than a small telescope; lower areal density Telescopes cost more than more massive Telescopes. Keywords: Space Telescope Cost Model, Parametric Cost Model 1. INTRODUCTION Parametric cost models for Space Telescopes provide several benefits to designers and Space system project managers. They identify major architectural cost drivers and allow high-level design trades. They enable cost-benefit analysis for technology development investment. And, they provide a basis for estimating total project cost. A survey of historical models found that there was no definitive Space telescope cost model [1]. Thus, there is a need for parametric Space Telescopes cost models. An effort is underway to develop single variable [2] and multi-variable [3] parametric Space telescope cost models based on the latest available data and applying rigorous analytical techniques. After the single and multi-variable parametric models were published, the data base underwent an independent review. The result of that review found several data points to be incorrect. As a result, the data base has undergone a complete review: some Telescopes were removed from the analysis; data for other Telescopes was revised; and new Telescopes were added to the data base. As a result of these changes, the cost models have changed. But the general findings remain unchanged: aperture diameter is the primary cost driver for large Space Telescopes; it costs less per square meter of collecting aperture to build a large telescope than a small telescope; and it costs more per kg to build a low areal density telescope than a massive telescope. One significant difference is that telescope cost is approximately 10% of total mission cost instead of 30%.
Peter Rausch - One of the best experts on this subject based on the ideXlab platform.
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unimorph deformable mirror for Space Telescopes environmental testing
Optics Express, 2016Co-Authors: Peter Rausch, Sven Verpoort, Ulrich WittrockAbstract:We have developed and manufactured a unimorph deformable mirror for Space Telescopes based on piezoelectric actuation. The mirror features 44 actuators, has an aperture of 50 mm, and is designed to reproduce low-order Zernike modes with a stroke of several tens of μm. We assessed the Space compliance by operating the mirror in thermal vacuum, and exposing it to random and sinusoidal vibrations, as well as to ionizing irradiation. Additionally, the operational life time and the laser power handling capability were tested. The mirror was successfully operated in thermal vacuum at 100 K. We report on the conducted tests and the methods used to evaluate the mirror’s performance, and discuss the compliance with the demanded requirements.
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unimorph deformable mirror for Space Telescopes design and manufacturing
Optics Express, 2015Co-Authors: Peter Rausch, Sven Verpoort, Ulrich WittrockAbstract:Large Space Telescopes made of deployable and lightweight structures suffer from aberrations caused by thermal deformations, gravitational release, and alignment errors which occur during the deployment procedure. An active optics system would allow on-site correction of wave-front errors, and ease the requirements on thermal and mechanical stability of the optical train. In the course of a project funded by the European Space Agency we have developed and manufactured a unimorph deformable mirror based on piezoelectric actuation. The mirror is able to work in Space environment and is designed to correct for large aberrations of low order with high surface fidelity. This paper discusses design, manufacturing and performance results of the deformable mirror.
H. Philip Stahl - One of the best experts on this subject based on the ideXlab platform.
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Parametric Cost Models for Space Telescopes
2013Co-Authors: H. Philip Stahl, Todd Henrichs, Courtnay DollingerAbstract:Multivariable parametric cost models for Space Telescopes provide several benefits to designers and Space system project managers. They identify major architectural cost drivers and allow high-level design trades. They enable cost-benefit analysis for technology development investment. And, they provide a basis for estimating total project cost. A survey of historical models found that there is no definitive Space telescope cost model. In fact, published models vary greatly [1]. Thus, there is a need for parametric Space Telescopes cost models. An effort is underway to develop single variable [2] and multi-variable [3] parametric Space telescope cost models based on the latest available data and applying rigorous analytical techniques. Specific cost estimating relationships (CERs) have been developed which show that aperture diameter is the primary cost driver for large Space Telescopes; technology development as a function of time reduces cost at the rate of 50p per 17 years; it costs less per square meter of collecting aperture to build a large telescope than a small telescope; and increasing mass reduces cost.
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Update on parametric cost models for Space Telescopes
2011Co-Authors: H. Philip Stahl, Todd Henrichs, Alexander R. Luedtke, Miranda WestAbstract:ABSTRACT Parametric cost models are used to plan missions, compare concepts and justify technology investments. This paper updates an on-going effort to develop cost modes for Space Telescopes and summarizes how recent database changes have changed previously published preliminary results. While the models are evolving, the previously published findings are valid: telescope cost increases with aperture diameter; it costs less per square meter of collecting aperture to build a large telescope than a small telescope; lower areal density Telescopes cost more than more massive Telescopes. Keywords: Space Telescope Cost Model, Parametric Cost Model 1. INTRODUCTION Parametric cost models for Space Telescopes provide several benefits to designers and Space system project managers. They identify major architectural cost drivers and allow high-level design trades. They enable cost-benefit analysis for technology development investment. And, they provide a basis for estimating total project cost. A survey of historical models found that there was no definitive Space telescope cost model [1]. Thus, there is a need for parametric Space Telescopes cost models. An effort is underway to develop single variable [2] and multi-variable [3] parametric Space telescope cost models based on the latest available data and applying rigorous analytical techniques. After the single and multi-variable parametric models were published, the data base underwent an independent review. The result of that review found several data points to be incorrect. As a result, the data base has undergone a complete review: some Telescopes were removed from the analysis; data for other Telescopes was revised; and new Telescopes were added to the data base. As a result of these changes, the cost models have changed. But the general findings remain unchanged: aperture diameter is the primary cost driver for large Space Telescopes; it costs less per square meter of collecting aperture to build a large telescope than a small telescope; and it costs more per kg to build a low areal density telescope than a massive telescope. One significant difference is that telescope cost is approximately 10% of total mission cost instead of 30%.
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Preliminary multivariable cost model for Space Telescopes
Proceedings of SPIE, 2010Co-Authors: H. Philip Stahl, Todd HenrichsAbstract:Parametric cost models are routinely used to plan missions, compare concepts and justify technology investments. This paper reviews the methodology used to develop Space telescope cost models; summarizes recently published single variable models; and presents preliminary results for two and three variable cost models. Some of the findings are that increasing mass reduces cost; it costs less per square meter of collecting aperture to build a large telescope than a small telescope; and technology development as a function of time reduces cost at the rate of 50% per 17 years.
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Single-variable parametric cost models for Space Telescopes
Optical Engineering, 2010Co-Authors: H. Philip Stahl, Todd Henrichs, Christian Smart, Kyle Stephens, Frank A. PrinceAbstract:Parametric cost models are routinely used to plan missions, compare concepts, and justify technology investments. Unfortunately, there is no definitive Space telescope cost model. For example, historical cost estimating relationships CERs based on primary mirror diameter vary by an order of magnitude. We present new single-variable cost models for Space telescope optical telescope assembly OTA. They are based on data collected from 30 different Space telescope missions. Standard statistical methods are used to derive CERs for OTA cost ver- sus aperture diameter and mass. The results are compared with previ- ously published models © 2010 Society of Photo-Optical Instrumentation
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Preliminary cost model for Space Telescopes
Proceedings of SPIE, 2009Co-Authors: H. Philip Stahl, Frank A. Prince, Christian Smart, Kyle Stephens, Todd HenrichsAbstract:Parametric cost models are routinely used to plan missions, compare concepts and justify technology investments. However, great care is required. Some Space telescope cost models, such as those based only on mass, lack sufficient detail to support such analysis and may lead to inaccurate conclusions. Similarly, using ground based telescope models which include the dome cost will also lead to inaccurate conclusions. This paper reviews current and historical models. Then, based on data from 22 different NASA Space Telescopes, this paper tests those models and presents preliminary analysis of single- and multi-variable Space telescope cost models.