ai-aerospace/ams_data_full_2000-2020 huggingface dataset:
During the initial development phase of the whole-spacecraft shock isolation system, prototypes were  IA  I,  d  -m’  -nm,I-hg.-y..Dllm  TmMiat  4  e  a  ’5 0.I 0, 0,s D1 o_ 01  TI?. -1  Figure 16. Transient responses and shock response  spectra from impact test fabricated and shock tested using a  pneumatic impact gun. The shock  isolator was attached to two rigid steel  blocks and suspended from a test frame.  The impact occurred on the steel block  referred to as the “base” and the  accelerations were measured on both the  base and the “payload steel blocks.  Acceleration time histories and their  corresponding shock response spectra  for a typical test are shown in Figure 16.  Above the isolation frequency of this  shock isolator (100 Hz in the axial  direction and 250 Hz in the lateral  direction) over a magnitude of  attenuation is achievable.  This testing is very useful for  development of shock isolators.  However, this type of testing is missing  two essential ingredients to prove the  shock isolator’s ability to attenuate shock  loads. The launch community will place  more credibility on the shock isolator  testing if it includes (1) flight-like  pyrotechnic excitation and (2) flight-like flexible adjoining structures as opposed to rigid blocks: -  Shock tests were subsequently conducted using primacord for pyrotechnic excitation, launch vehicle  components, and a spacecraft emulator. The amount of primacord was experimentally adjusted until  flight-like shock acceleration levels were measured at the spacecraft interface. Accelerations were  measured in all directions at several locations. Figure 17 shows acceleration time histories and shock  response spectra from the test of a whole-spacecraft shock isolator. Data is shown for accelerometer  locations both forward and aft of the isolator. The excellent attenuation performance of the shock isolator  can be seen in both the time and frequency domains.  98
m  s  lo  1 0' 1 0-  1 0' - - m  f 10) t  d lol  1 on  10.)  10' 1 0'  Figure 17. Pyrotechnic shock test results of a shock ring  VALPE Fliaht ExDeriment  The Air Force Research Laboratory and the Air Force Space  VALPE, Vibro-Acoustic Launch Protection Experiment. VALP  reduction techniques on board two flights of a NASA sounding  and hybrid (passive-active) whole-spacecraft vibration  isolation was one component of this program. For the first  flight, only a passive SoftRide ShockRing isolation system  was flown. For the second flight, an active vibration isolation  system was also implemented using the ShockRing as the  passive stage. This launch vehicle produces very high  quasi-static acceleration loads (up to 20 g's) and very high  dynamic loads (up to 40 g's). Therefore, designing the  isolation system for strength while maintaining the required  flexibility was a challenge.  The first flight was launched from NASA Wallops Flight  Facility at Wallops Island, VA in November 2002. Figure 18  shows the flight one payload hardware prior to integration  into the launch vehicle. Due to the small payload envelope  for this experiment, the ShockRing was a compact design.  The ShockRing, mounted just below the payload  electronics, has a diameter of 32 cm and a height of 4.5 cm.  The ShockRing was designed to protect the mission Test Program sponsored a program called  E demonstrated several vibration/acoustics  rocket, the Terrier Improved-Orion. Passive  specific electronics for monitoring the experiment launch  environment. Figure 19 shows the launch vehicle and the  lift-off.  99
L  5 i ___.  Figure 19. VALPE Terrier Improved-Orion on launch rail and November 02 launch  Flight data was recovered by telemetry from the  entire flight. Flight data for the lateral direction for the  second stage burn is shown in Figure 20, where the  data in red is below the isolation system and data in  yellow is on the payload side. This data shows that  the ShockRing reduced the acceleration levels even  in the lateral direction, which is not as compliant and  highly damped as the axial direction.  Figure 20. VALPE flight data from last 20  seconds of flight, below and above the  isolation system  Falconsat-3  In 2006, under a program sponsered by the Air Force Research Laboratory, a whole-spacecraft  ShockRing developed for the Air Force Academy's FalconSAT-3 satellite will provide high frequency  attenuation during launch on an Atlas V launch vehicle. FalconSAT-3 is a 50 kg experimantal satellite that  will be one of the first secondary payloads to fly on ESPA. FalconSAT-3 is a unique satellite that has a  boom that protrudes into the center of ESPA and through the center of the ShockRing. The ShockRing  provides an open center for the FalconSAT-3 boom, attenuate in both the satellite axial and lateral  direction,s and provides a rigid connection to ESPA.  The ShockRing isolation system adds just over five centimeters to the stack height of the system and just  over 3 kg to the assembly. Figure 21 below shows the FalconSAT-3 qualification model during testing with  the ShockRing mounted directly underneath. Figure 22 is test data from system level vibe tests performed  with and without the ShockRing isolation system. Acceleration data was recorded at the top of the satellite  during an axial direction high level random test. Overall grms levels were reduced from 21 grms to 8 grms.  Currently CSA is on schedule to deliver flight hardware to the Air Force Academy in early 2006.  100
I -  1 IYUI G 1L I. YUc.IlIl~UbIWII LGSU VI F.  ShockRing stack on the shaker 10-  Urns wlth ShockRirp7.7858  IO'  Figure 22. Axial direction test data with and without  the ShockRing I 1  1 o2 1 o3  Frsquancy (W  Conclusion  There is a need to reduce launch loads on spacecraft so that spacecraft and their instruments can be  designed with more concentration on orbital performance rather than launch survival. A softer ride to orbit  will allow more sensitive equipment to be included in missions, reduce risk of equipment or component  failure, and possibly allow the mass of the spacecraft bus to be reduced. These benefits apply to military  as well as commercial spacecraft.  For all of the missions flown to date, the patented SoftRide UniFlex, MultiFlex, and ShockRing whole-  spacecraft vibration and shock isolation systems have proved to be a very effective means of reducing  spacecraft responses due to the broadband structure-born launch environment.  From both the transient data and the waterfall PSDs, it is clear that the SoftRide whole-spacecraft  vibration isolation systems performed very well to reduce structure-borne vibration levels transmitted to  the spacecraft. The isolation system was designed specifically to reduce the effects of solid motor  resonant burn in the 45 Hz to 60 Hz frequency range, which it did very well. It should also be noted that the  SoftRide vibration isolation system provided extreme reductions of shock and structure-borne acoustics at  higher-f requencies.  The isolation system hardware design was elegant in its simplicity, which ultimately played a great part in  its acceptance by both the spacecraft and launch vehicle manufacturers. The SoftRide isolation systems  are simply inserted at an existing field joint. No flight hardware changes were required. The only change  was to the guidance and control algorithms to account for bending frequency changes introduced by the  isolation system. In the end, the choice to fly the isolation system proved to be a tremendous risk-  reduction for the spacecraft by drastically increasing the spacecraft margins. Because of the success of  these flights, this isolation system design is being used on several upcoming flights.  101
References  1 . Orbital Sciences Corporation, “Taurus Launch System Payload User’s Guide”, Release 3.0,  September, 1999  2. Orbital Sciences Corporation, “Minotaur Payload User’s Guide”, Draft version, April 26, 2001  3. Schoneman, S., Buckley, S., et. ai, “Orbital Suborbital Program (OSP) “Minotaur” Space Launch  Vehicle: Low Cost Space Lift For Small Satellites Using Surplus Minuteman Motors”, AlAA Paper  AIAA-2000-5068, AlAA Space 2000 Conference, September 19-21,2000, Long Beach, CA.  102
Summary of the New AlAA Moving Mechanical Assemblies Standard  Brian W. Gore’  Abstract  A new American Institute of Aeronautics and Astronautics (AIAA) standard entitled “Moving Mechanical  Assemblies for Space and Launch Vehicles,” AIAA-S-114-2005, has been created. It is based on Military  Specification MIL-A-835776, which was cancelled by the Department of Defense in the mid-1 990’s. The  new standard supersedes a Technical Operating Report (TOR) (prepared by Brian W. Gore of The  Aerospace Corporation with support from the Air Force Space and Missile Center and the National  Reconnaissance Office, which was a “cleaned-up,’’ same-format version of MIL-A-83577B) and has  already been used as a compliance document in several recent acquisitions and Requests For Proposals.  This paper outlines some of the more significant changes and additions made in the new AlAA MMA  Standard since the previous TOR and MMA specification were released.  Introduction  The U.S. Air Force (USAF) Space and Missile Center (SMC) and the National Reconnaissance Office  (NRO) have recently established policies supporting and requiring government, industry, and professional  society specifications and standards for new acquisitions.  NAn  S414-20@5  -1 Standard  Moving Mechanical Assemblies  for Space and Launch Vehicles  The Aerospace Corporation, El Segundo, CA  Proceedings of the 3dh Aerospace Mechanisms Symposium, Langley Research Center, May 17- 19,2006  103
The new AlAA standard, AIAA-S-114-2005, is one of the first products of the recent Specifications and  Standards Revitalization Program undertaken by the USAF’s SMC. They asked the AlAA to engage  appropriate subject matter experts to develop five consensus standards to be used as compliance  documents for SMC (and potentially NRO) acquisition activities. These five standards were:  1. AIAA-S-110-2005, “Space Systems - Structures, Structural Components, and Structural  Assemblies  2. AIAA-S-111-2005, “Qualification and Quality Requirements for Space-Qualified Solar Cells”  3. AIAA-S-112-2005, “Qualification and Quality Requirements for Space-Qualified Solar Panels”  4. AIAA-S-113-2005, “Space Systems - Criteria for Explosive Systems and Devices Used on  Launch and Space Vehicles”  5. AIAA-S-114-2005, “Moving Mechanical Assemblies for Space and Launch Vehicles”  Three other standards are currently beginning the same development process, as of the time of  publication of this paper; these involve  1. Space System Electrical Power System Design,  2. Space System Electromagnetic Compatibility Requirements, and  3. Space System Mass Properties Control  A memorandum from USAF Lt. Gen. Brian Arnold to SMC dated 14 January 2003 and titled “Policy Letter  on Specification and Standards Usage at SMC outlines the framework for using specifications and  standards as a key part of their acquisition, contracting, and program management. Some key excerpts  from that memo include:  “The unintentional result (of reducing the use of specifications and standards as compliance  documents through “Acquisition Reform”) was that technical baselines and processes were  compromised.”  “There is no intent to return to the pre-acquisition reform approach of using an excessive  number of specs and standards. A list of high priority critical specs and standards is  being.. .established for appropriate use.”  “The baseline list of specs and standards will be used in a less prescriptive manner than in  the past.”  With these ideas in mind, the Moving Mechanical Assembly Standard was created with the utmost  thought toward incorporating those requirements that are common to most MMAs for space and launch  vehicles. The requirements stated are a composite of those that have been found to be cost-effective for  high reliability space and launch vehicle applications.  The standard is the result of contributions received from many individuals, most notably those on the  AlAA MMA Committee on Standards (Cos). Although the committee started out about twice as large, at  the time of approval the actively participating members of the AlAA MMA COS were:  Stephen Brock, Liaison  Ken Emerick, Co-Chair  Brian Gore, Co-Chair  Michael Pollard, Co-Chair  Dave Putnam  Dave Richman  Paul Reynolds  Bert Timmerman AlAA  Space Systems/Loral  The Aerospace Corporation  Lockheed Martin Corporation (Denver)  Lockheed Martin Corporation (Sunnyvale)  The Boeing Company  Northrop Grumman Corporation  Hi-Shear Technology Corporation  104
The above consensus body approved the document and the AlAA Standards Executive Council accepted  the standard for publication in June 2005. It can be downloaded for purchase ($39.95, or $31.95 for AlAA  members) from the AlAA website at  httu://www.aiaa.ora/content.cf m?~aueid=363&id=l366&Tvue=StoreProduct&LaverlD=51  Description  The new AlAA MMA standard specifies general requirements for the design, manufacture, quality control,  testing, and storage of MMAs to be used on space and launch vehicles. It is applicable to the mechanical  or electromechanical devices that control the movement of a mechanical part of a space or launch vehicle  relative to another part. The requirements apply to the overall MMA as well as to the mechanical  components and instrumentation that are an integral part of these mechanical assemblies.  Not all requirements in the standard are of equal importance or weight. They have been divided into three  categories of importance, ranging from requirements that are imposed on all applications to examples of  acceptable designs, items, and practices. The relative weighting of requirements is an important  consideration when tailoring the standard to specific applications and in making trade studies of  alternatives. Three weighting factors are incorporated in the standard:  1. “Shall”  2. “Shall, where practical”  3. “P ref e rred/S hou Id/May”  Note that the old MMA specification designated four separate weighting factors, with this standard  essentially combining the lowest two in the hierarchy. The use of the weighting factors in the standard is  intended to assist in the tailoring of requirements to specific appiications and to assist contractors in the  design process. Detailed definitions and scope of these weighting levels are described in the standard.  Unlike the uniform, one-format-fits-all of many military specifications, this particular document reflects the  general consensus of the industry in what is required for today’s MMAs from a design, build, inspection,  and test perspective. The document was designed to be more “user-friendly” than the old MMA  specification as it was consciously re-organized to flow simultaneously from general to specific, as well as  along the design and development life of MMAs. To provide an illustration of this new organization, the  chapters and major subheadings are listed in Table 1.  105
Table 1. Organization of MMA Standard  1 Scope  2 Tailoring  3 Applicable Documents  4 Vocabulary  5 General Design Requirements  5.1 Performance Requirements  5.2 Environmental Design Requirements  5.3 Physical Requirements  5.4 Electrical and Electronic Requirements  5.5 Structural Requirements  5.6 Reliability  6 Component Design Requirements  6.1 Fasteners  6.2 Retention and Release Devices  6.3 Pivots and Hinges  6.4 Cable Systems  6.5 Springs  6.6 Dampers  6.8 End-of-Travel Latches  6.9 Gearings  6.1 0 Electric Motors  6.1 1  6.1 2 Switches  6.1 3 Gears  6.1 4 Pressurized Components  7.1  7.2 Materials  7.3 Lubricants  7.4 Hard Coatings  7.5 Contamination  8.1  8.2 Test Fixtures  8.3 Test Instrumentation  8.4 Test Plans and Procedures  8.5 Development Tests  8.6 Qualification and Proto-qualification Tests  8.7  8.8 Vehicle Level Acceptance Tests  8.9  8.10 Modifications, Rework, and Retesting 6.7 stops  Power and Signal Transfer Components  7 Parts, Materials, and Processes Requirements  General Parts, Materials, and Processes  8 Testing and Inspection Requirements  Parts, Materials, and Process Controls  Component and Subsystem Level Acceptance Tests  Pre-launch Validation Testing and Inspection  9 Bibliography  Annex A  (Informative) Static Torque or Force Margins at Different Coordinate Points  106
Highlighted Changes  Overall flow - easier to uselfind information  As stated above, it was an early and deliberate action by the COS to reformat the AlAA MMA Standard to  be easier to use and find information than the previous military specification document. Before any work  was done on the technical content, the co-chairs spent a notable - and ultimately worthwhile - amount of  time determining the current organization, deleting obvious subject items and inserting placeholders that  were later filled in regarding new areas of interest and importance.  The co-chairs then rearranged the remaining text into the corresponding sections of the new format, and  the committee went to work to generate and compile a list of discussion comments. It was this list that  formed the focus of the COS efforts. Teleconferences on a bi-weekly, then weekly, then almost daily basis  toward the end were the main forum of COS communication, augmented by a members-only, AIAA-  hosted website which stored and organized pertinent and necessary documentation.  ADDroximatelv 400 comments aenerated, submitted. and disDositioned.  After the COS reviewed the base document and compiled the aforementioned list, they used the  teleconferences and two, multiple-day, face-to-face “summit” meetings to work through the list. Several of  the committee members passed the working document [initially issued as The Aerospace Corporation  Technical Operating Report TOR-2004(8583)-1] to their colleagues or certain specialists to solicit  additional insightful comments. The COS spent the majority of these meetings discussing the merits of the  particular comments submitted, grouped as either general, editorial, or technical; a breakdown of the  comments in the list is shown in Figure 1.  Breakdown of Submitted MMA Std  Comments  %- General  8%  Figure 1. Breakdown of Submitted MMA Standard Comments  Moreover, after the final draft of the standard was prepared, AlAA initiated a 30-day public review period,  which yielded still more comments, for a grand total of approximately 400 submissions by members of  Aerospace, many contractors, NASA, etc. Figure 2 illustrates the approximate number of comments by  submitting individuals. Some of the people listed were points of contact from their entire organization.  107
Comments by Contributor  Figure 2. Number of Comments by Contributor  Conciseness/deletion of DeriDheral areas  There were many areas of the old MMA specification that were deemed by consensus to be out of scope  for a modern moving mechanical assembly standard. Since we were no longer bound by the standard  template, there was freedom to make this document more relevant overall. As such, several sections  were deleted altogether in recognition that there were virtually always other documents or specifications,  either governmental or internal to contractors that existed to govern those areas. Some of these subject  areas included identification and marking, certain details on processes and controls, structural  requirements, specific environmental conditions, etc. However, many such sections were minimized and  maintained as a consideration guide for younger engineers, or simply as a reference pointer to the  appropriate document, such as the new AlAA Structures Standard, MIL-STD-1540E (the environmental  testing standard), etc. This scope is one of the main utility features for which the COS was striving. One  metric of this conciseness may be indicated by the relative word counts of the documents, as illustrated in  Table 2.  Table 2. Word Count of Evolving MMA Documents  TOR-2004( 8583)-1 I 24,000  AIAA-S-114-2005 19,000  Areas rechecked for modern validity  There were several peripheral areas relating to MMAs that were also verified for modern validity, such as  contamination, lubrication, electrostatic discharge, etc. For these particular areas, Aerospace and  contractor experts were consulted to obtain an insight as to what governing documents existed for their  respective disciplines. These were, in turn, referenced in the MMA standard where appropriate, leaving  the details to those other documents, unlike the original MMA specification that contained many of the  details.  108
References  AIAA-S-114-2005, Movinq Mechanical Assemblies Standard for Space and Launch Vehicles,  American Institute of Aeronautics and Astronautics standard, July 2005.  MIL-A-835776, Militarv Specification - Assemblies, Movina Mechanical, For Space And Launch  Vehicles, General Specification For, 1988.  Gore, Brian W., Movinq Mechanical Assemblies Standard for Space and Launch Vehicles (Draft 11,  The Aerospace Corporation Technical Operating Report, TOR-2004(8583)-1, July 2004.  Acknowledgements  The author recognizes several individuals who not only made this paper possible, but were supportive of  the entire effort behind its subject matter. Mr. Dave Davis of SMC/AX, through Valerie Lang, John Ingram-  Cotton, and Joe Meltzer from the Aerospace Office of the Chief Engineer, provided the funding necessary  to complete all of the work in getting the TOR and AIM Standard prepared and released. Ken Emerick of  Space Systems/Loral and Mike Pollard of Lockheed-Martin (Denver) were loyal and admirable co-chairs  on the AIAA MMA Committee on Standards. Their leadership work is to be commended. Stephen Brock  of AIAA served as COS Liaison, and without him, the COS would still be trying to figure out how to use the  COS website, and probably still be editing changes. Certainly not to be forgotten, Mike Hilton, Tom  Trafton, Leon Gurevich, and AI Leveille (retired) of The Aerospace Corporation helped get the ball rolling  in the right direction by providing some historical perspective on the MMA specification and its contents.  111