NASA/George C. Marshall Space Flight Center, Procurement Office, Marshall Space Flight Center, AL 35812

A -- INTEGRATED MODELING AND ANALYSIS OF FLEXIBLE MULTIBODY SYSTEMS INCLUDING OPTICAL ELEMENTS FOR POINTING CONTROL SYSTEMS PERFORMANCE EVALUATION SOL 8-1-8-ED-B8054 DUE 030698 POC Glynda H. Meeks, Contract Specialist, Phone (205) 544-0422, Fax (205) 544-9080, Email glynda.meeks@msfc.nasa.gov -- Valerie N. Holmes, Contracting Officer, Phone (205)544-0314, Fax (205)544-4400, Email valerie.holmes@msfc.nasa.gov WEB: Click here for the latest information about this notice, http://nais.nasa.gov/EPS/MSFC/date.html#8-1-8-ED-B8054. E-MAIL: Glynda H. Meeks, glynda.meeks@msfc.nasa.gov. NASA/MSFC plans to issue a Request for Quotation (RFQ) for INTEGRATED MODELING AND ANALYSIS OF FLEXIBLE MULTIBODY SYSTEMS INCLUDING OPTICAL ELEMENTS FOR POINTING CONTROL SYSTEMS PERFORMANCE EVALUATION: Background -- Since the performance of pointing control systems involve the control and orientation of individual elements of a mechanical system which often includes optical elements, the design of a control system that meets performance requirements depends on how well the dynamics of the mechanical system and thermal properties and environments are understood and can be modeled. These systems are typically composed of several elements, each of which might have structural modes of concern to the control system designer, large relative angular and translational displacements and closed mechanical topologies. The computer simulation tool, TREETOPS (TREE TOPology), has been developed and used at MSFC to model these complicated mechanical systems. TREETOPS is a multibody dynamics and control simulation program developed for analysis of the dynamics and control of complex, flexible, multibody systems. Developed under NASA funding, TREETOPS is available to industry and institutions working on NASA research. TREETOPS in conjunction with various tools of MATLAB (MATHematical LABoratory is a commercial software package from The Mathworks, Inc.) has provided an effective approach for the control engineer to begin the development of integrated modeling techniques of mechanical, thermal, optical and control systems to analyze pointing systems performance. While TREETOPS is a state-of-the-art tool and has been useful in solving past problems, it is being upgraded on a continuous basis to account for the intricacies of an ever increasing sophistication of control systems missions. This task involves the continuing development of the TREETOPS tool and its application to ongoing programs at MSFC. TASK DESCRIPTION: The contractor shall perform the following tasks. 1. TREETOPS Development: Modify and improve the TREETOPSsimulation program in the areas of dynamical fidelity and usefulness to the control system designer. This shall include the development of multidisciplinary functions such as control, optics, flexible and inflatable structures, and thermally induced deformations. In many instances modifications will be prompted by test data from actual structures in the laboratory. Provide support in the areas of dynamics and simulation of flexible multibody systems. Maintain and upgrade TREETOPS as required to accommodate new problems. 2. AXAF On-Orbit Performance Assessment: The AXAF Project is in the spacecraft integration phase where actual test data is becoming available which will provide the best characterization of the flight hardware. The flight software testing and verification is also being performed which may require the modification of hardware and software operational models. A user defined control system algorithm shall be implemented into the TREETOPS AXAF model which utilizes the latest hardware and structural models including the reaction wheel vibration isolation model. 3. Isolation for Microgravity: A key aspect of control system design for microgravity vibration isolation systems is the ability to conduct high-fidelity simulation of the system with the controller in the loop. This analysis must account for the multibody dynamics, structural flexibility, and controller architecture of the system. TREETOPS shall be used to model the isolation system and control system including flexible umbilical connections, actuator mass and dynamics, and payload dynamics. This detailed modeling is necessary to support the design and testing of an isolation system for the Space Station Microgravity Glovebox. TREETOPS was also used to support a technical assessment of the Boeing Active Rack Isolation System (ARIS). Further TREETOPS model development and refinement is necessary to support ongoing design iterations of ARIS as well as provide support during the verification flight testing and operation of ARIS on the Space Station. 4. SPARCLE: A TREETOPS model of the Space Readiness Coherent Lidar Experiment (SPARCLE) optical mechanism design shall be required for determination of pointing performance to support error budget analysis, design trades studies, and pointing system requirements. 5. Shooting Star Experiment: Continue development of an integrated optical and inflatable structures TREETOPS model using test data from thermal vacuum test of the SSE inflatable structure and CODE V simulations of the optical design. This procurement is being conducted under the Simplified Acquisition Procedures (SAP). NASA/MSFC intends to purchase the research from the University of Alabama in Huntsville pursuant to FAR 13.106 as part of the University Research Basic Ordering Agreement (BOA) Program . This sole source procurement is based on the university's domain expertise in the area of dynamics and control of flexible multibody systems. Interested firms have 15 days from the publication of this synopsis to submit in writing to the identified point of contact, their qualifications/capabilities. Such qualifications/capabilities will be used solely for the purpose of determining whether or not to conduct this procurement on a competitive basis. Responses received after the 15 days or without the required information will be considered nonresponsive to the synopsis and will not be considered. A determination by the Government to not compete this proposed effort on a full and open competitive basis, based upon responses to this notice is solely within the discretion of the Government. Oral communications are not acceptable in response to this notice. All responsible sources may submit an offer which shall be considered by the agency. An Ombudsman has been appointed. See Internet Note "B". (0051)

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