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The McDonnell Douglas Delta family of launch vehicles, in its more than 30-year history, has proven to be the most reliable spacecraft deployment platform for both the US government and the private sector. This success is due to the continuous and focused application of advanced, affordable engineering and manufacturing technologies in all stages of the design, fabrication, assembly, quality assurance, and launch. One of the recent technological breakthroughs that has enhanced the Delta's service capabilities is the development and use of large composite structures in critical components. Among these structures is the payload fairing, which acts as a protective shroud for the spacecraft. Traditional composite manufacturing techniques, however, are very labor-intensive and time-consuming.

The Space Station Freedom program requires long-life thermal control coatings that are stable in low Earth orbit (LEO). To provide designers with a variety of coatings and optical properties, improvements were made to existing coatings, and new thermal control coatings were developed. Anodized aluminum was demonstrated to be an acceptable substrate for inorganic thermal control coatings such as Z-93. Mixtures of Z-93 with stable black oxides provided a wide range of optical properties and were stable in a simulated LEO environment. In addition, sulfuric acid anodized aluminum was developed to a production status to provide controlled optical properties for many aluminum alloys.

This paper presents an overview of the design and operation of the internal thermal control system (ITCS) developed for Space Station Freedom by the NASA-Johnson Space Center and McDonnell Douglas Aerospace to provide cooling for the resource nodes, airlock, and pressurized logistics modules. The ITCS collects, transports, and rejects waste heat from these modules by a dual-loop, single-phase water cooling system. ITCS performance, cooling, and flow rate requirements are presented. An ITCS fluid schematic is shown and an overview of the current baseline system design and its operation is presented. Assembly sequence of the ITCS is explained as its configuration develops from Man Tended Capability (MTC), for which node 2 alone is cooled, to Permanently Manned Capability (PMC) where the airlock, a pressurized logistics module, and node 1 are cooled, in addition to node 2.

A CELSS has been defined based on current or near-term technology. The CELSS was sized to support the metabolic load of four people on the Moon for ten years. A metabolic load of 14 MJ/person/day is assumed, including an average of 2.6 hr of EVA/person/day. Close to 100% closure of water, and oxygen, and 85% closure of the food loop is assumed. With 15% of the calories supplied from Earth, this should provide adequate dietary variety for the crew along with vitamin and mineral requirements. Other supply and waste removal requirements are addressed. The basic shell used is a Space Station Freedom 7.3 m (24 ft) module. This is assumed to be buried in regolith to provide protection from radiation, meteoroids, and thermal extremes. A solar dynamic power system is assumed, with a design life of 10 years delivering power at 368 kWh/kg. Initial estimates of size are that 73 m2 of plant growth area are required, giving a plant growth volume of about 73 m3.

This paper defines the value of free-flying cameras to the Space Station. The use of free-flying cameras is an alternative to reliance on fixed cameras. The analysis is based upon results from recent neutral buoyancy evaluations of a free-flying camera known as the Supplemental Camera and Maneuvering Platform (SCAMP). SCAMP was evaluated for inspection and viewing capabilities that will be required by Space Station. Test results demonstrated that a free-flying camera could be used effectively for inspecting structure, viewing labels, providing views for control of extravehicular robotics (EVR) and for ground assistance during extravehicular activity (EVA) tasks.

The objective of this paper is to present results of MDA's payload vibration isolation system research and development program. A unique isolation system with passive or active capabilities designed to provide isolation down to 10-6 g was developed and tested in our 1-g testbed under simulated microgravity conditions. Fluid and electrical umbilicals are also included in the system. The established isolation system performance requirements were met and the testbed data were used to refine our analytical models for predicting flight performance. Simulations using an updated Space Station configuration showed that the payload microgravity requirement can be met by upgrading the hardware from laboratory to flight tolerances and improving the control system design. The next step is to flight test the systems verified in 1 g on the STS/SPACEHAB using a middeck locker size development unit.

The paper describes the development, implementation, and benefits of a real-time statistical process control (SPC) data acquisition and response system. The system has been installed on four production CNC riveters and provides enhanced, in-process control of automated fastening machine performance. Each system employs commercially available SPC components. These components, coupled with real-time data acquisition computers, have been integrated with the riveter's controllers and sensors to detect process anomalies as they occur. Real-time knowledge of fastening machine performance is the benefit of this system's approach to SPC. Fastener quality is ensured during the fastening cycle, not after sequences (and perhaps hundreds of rivets) have been completed.

A novel robot architecture has been developed which promises cost savings in a variety of applications in Space and on Earth. Utilizing cables in order to effect motion in a general workspace provides large weight savings, as well as high end effector stiffness. The architecture has been built and successfully tested in space. The capability of the robotic system to actuate those switches, dials, and buttons expected in space environments, as well as to read displays and transmit video to earth for operator feedback have been proven, and are discussed herein.

Tactical aircraft have tire lives as low as 3-5 landings per tire causing excessive support costs. The goal of the Improved Tire Life (ITL) program was to begin developing technology to double aircraft tire life, particularly for tactical aircraft. ITL examined not only the tire, but also aircraft/landing gear design, aircraft operations, and the operational environment. ITL had three main thrusts which were successfully accomplished: 1) development of an analytical tire wear model, 2) initiation of technology development to increase tire life, and 3) exploration of new and unique testing methods for tire wear. This paper reports the work performed and the results of the USAF sponsored ITL program.

This paper is focusing on considerations pertaining to riveting/fastening systems and assembly methodology currently in use for large aircraft fuselage structures. Discussion of process principles on which current systems are based is addressing distribution of rivets along the aircraft structure, riveting/fastening systems and equipment flexibility. An attempt was made to predict the most probable future equipment development trends based on the need for more efficiency in all aircraft structural assembly and in high level and final assembly areas.