MODIFICATION
66 -- X-RAY MIRROR METROLOGY STATION
- Notice Date
- 10/30/2003
- Notice Type
- Modification
- Contracting Office
- NASA/Goddard Space Flight Center, Code 210.M, Greenbelt, MD 20771
- ZIP Code
- 20771
- Solicitation Number
- 4200033848
- Response Due
- 11/12/2003
- Archive Date
- 10/30/2004
- Point of Contact
- Eric Jackson Newman, Contract Specialist, Phone (301) 286-4240, Fax (301) 286-1720, Email Eric.J.Newman@nasa.gov
- E-Mail Address
-
Email your questions to Eric Jackson Newman
(Eric.J.Newman@nasa.gov)
- Description
- THIS NOTICE CONSTITUTES AMENDMENT NO. 3 TO THE COMBINED SYNOPSIS/RFQ FOR X-Ray Mirror Metrology Station. Companies shall acknowledge all amendment(s) in their quote. This notice serves as the official amendment to subject synopsis/RFQ and a written amendment will not be issued. The purpose of this amendment is to post and respond to questions from industry. The questions and answers to the questions are as follows: A. Question: There is repeated reference to a measurement accuracy (or, equivalently, a "fine radial motion" accuracy") of 0.01 micron (10 nm) rms. We understand that this clearly applies within each separate axial scan measurement of the test piece. Our question is whether there are separate requirements from scan to scan. Specifically, we ask whether there are separate requirements for the measurement of 1. the average end-to-end slope among the axial scans (or "delta-radius"); 2. the variation of end-to-end slope among the axial scans (or "delta-delta-radius"); and 3. the variation of average radius among the axial scans (or "roundness"). Response: 1. As a point of information -- if the two ends of the scan are off by 10 nm, in opposite directions (worst direction, 1 sigma statistics), over the full 200 mm scan, the corresponding angle error is 20 nm / 200 mm = 0.1 microradian ~ 0.02 arcsecond. 2. The questions above can be answered by reference to our Constellation-X angular resolution error budget; the corresponding error allocations for errors #'s 1-3 above are documented. If (conservatively) we budget 1/16th of this error for a metrology contribution, and taking into account that we root-sum-square to combine terms in the error budget [for example, if terms a and b are equal, their sum is sqrt(a^2 + b^2) = sqrt(2) * a, NOT 2* a], the following error allocations for the terms listed above result: 2.1. The average end to end slope error would also be called the 'cone angle error' and is allocated 2.5 arcsecond rms; this could be calculated from the derivative of the axial scans with respect to axial position (slope). 2.2. The variation of end-to-end slope among the axial scans would be called delta-delta-radius and is allocated 0.125 arcsecond rms; this also would be calculated from the derivative of the axial scan with respect to axial position. 2.3 The variation of average radius would also be called roundness and is allocated 0.75 microns (750 nm). Averaging of successive axial scans in the azimuthal direction, if there are sufficient of them, is permissible if it helps reduce noise and if the resulting average can still have 2 degree (~ 1/30th of the azimuthal width) resolution on the part under measurement with the time frame in the statement of work. B. Question: We have identified yet some technical points that could impact the cost of the measuring system and we need the following additional information : -confirm that the object (mirror) to be measured shall not move during measurement and that it is as close as possible maintained vertically to avoid deformations -confirm that, as consequence of the previous item, it is the axis of the cone that is tilted with respect to the vertical direction (i.e. Z' is the theoretical axis of the cone) Response: - we strongly prefer that the part not move during measurement; otherwise offerers must design in a very low vibration system and take responsibility for movement of the very thin part at the specified precision level. We expect this amounts to a requirement that the test object be stationary. - The preferred gravity orientation of the part is "near" vertical, i.e. with the gravity vector parallel to the axis of the cone. Thus Z' is a motion parallel to the cone surface, and Z (vertical) should be antiparallel to gravity. The due date for receipt of offers is extended to 11/12/03. Companies shall provide the information stated in the synopsis/RFQ posted on the NASA Acquisition Internet Service (NAIS) on 11/12/03. Documents related to this procurement are available over the Internet and are in Microsoft Office 97 format and reside on the World Wide Web (WWW) server which may be accessed using a WWW browser application. The Internet site, or URL, for the NASA/GSFC Business Opportunities home page is http://prod.nais.nasa.gov/cgi-bin/eps/bizops.cgi?gr=CL&pin=51
- Web Link
-
Click here for the latest information about this notice
(http://prod.nais.nasa.gov/cgi-bin/eps/bizops.cgi?gr=D&pin=51#107838)
- Record
- SN00462419-W 20031101/031030213430 (fbodaily.com)
- Source
-
FedBizOpps.gov Link to This Notice
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