Method for optimal configuration of an ECLSS on the Space Station Freedom

The establishment of a permanently manned Space Station represents a substantial challenge in the design of a life support system, specifically in the need to supply a large crew for missions of extended duration. The Space Station will evolve by time phased modular increments delivered and supplied by the Space Shuttle and other advanced launch systems. With the addition of each subsequent phase or alteration of mission duties, the requirements of the Station may differ from previous phases of development. With the addition of future crews and pressurized volume throughout the lifetime of the Space Station, change-out of individual subsystems may be necessary in order to meet the performance, safety, and reliability levels required from the Environmental Control and Life Support System (ECLSS). The analysis of this system growth demands the capability for advanced, integrated assessment techniques so that the unique mission drivers during each phase and mission scenario may be identified and evaluated. In order to determine the impacts of the interdependency between the ECLSS, the crew, the various user experiments, and the other distributed systems, consideration must be given to all Space Station resources and requirements during the initial and subsequent evolution phase. Therefore, it is necessary for analysis efforts to study the long term effects of established designs. These studies must quantify the optimal degree of loop closure within the capabilities of existing and future technologies including any resulting maintenance and logistics requirements. In addition, the necessity for subsystem retrofit during the lifetime of the Station must be examined. The source of system requirements due to long term exposure to the microgravity environment is illustrated, the criticality of the ECLSS functions is reviewed, and a method is described to develop an optimal design during each configuration based on the cross-consumption of Station resources. A comparison utilizing this procedure is discussed

Strategy for the reduction of total integrated fluid logistics to the Space Station Freedom

The use of an integrated environmental control and life support system (ECLSS) and secondary propulsion system (SRS) on the Space Station Freedom (SSF) has many potential advantages. Through the metabolism of food, the crew on-board the station will produce carbon dioxide as a waste gas and an excess of water in the form of urine and condensate. The processing of these waste fluids by the ECLSS could produce quantities of oxygen that would eliminate the need for cryogenic oxygen resupply and hydrogen, carbon dioxide, and/or methane that could be used with the addition of a resistojet system to provide a constant low thrust for station. This additional thrust would represent significant savings in required hydrazine resupply

Soyuz/ACRV accommodation study

Included is a set of viewgraphs that present the results of a study conducted at the LaRC Space Station Freedom Office at the request of the Space Station Freedom Level 1 Program Office and the JSC ACRV Project Office to determine the implications of accommodating two Soyuz TM spacecraft as Assured Crew Return Vehicles (ACRV) on the Space Station Freedom (SSF) at the Permanently Crewed Capability (PCC) stage. The study examined operational as well as system issues associated with the accommodation of the Soyuz for several potential configuration options. Operational issues considered include physical hardware clearances, worst case Soyuz departure paths, and impacts to baseline operations such as Pressurized Logistics Module (PLM) exchange, Space Station Remote Manipulator System (SSRMS) attachment, Extravehicular Activity (EVA), and automatic rendezvous and docking (AR&D). Systems impact analysis included determining differences between Soyuz interface requirements and SSF capabilities for the Electrical Power System (EPS), Thermal Control System (TCS), Communications and Tracking (C&T), Audio-Video Subsystem (A/V), Data Management System (DMS), and Environmental Control and Life Support System (ECLSS). Significant findings of this study have indicated that the current AV capability of the Soyuz will need to be increased to provide adequate departure clearances for a worst case escape from an uncontrolled SSF and that an interface element will be required to mate the Soyuz vehicles to station, provide for AR&D structural loads, and to house Soyuz-to-SSF system interfaces

Paper Session III-B - Utilization of Common Pressurized Modules of Space Station Freedom

Typical of past space projects following preliminary design review, most of the major Space Station critical subsystems will be required to reduce costs, weight, and power consumption prior to flight article hardware production. One such subsystem consists of the pressurized modules which provide the environment in which the crew members live and work. The current baseline station has two types of U.S. pressurized vessels: four resource nodes, and two modules 44 feet in length which must be transported to orbit nearly empty due to structural weight alone. Thus, user and system racks must be outfitted on-orbit rather than integrated on the ground. In this feasibility study, a shorter common pressurized module concept is assessed. The size, transportation, location, and accommodation of system racks and user experiments are considered and compared to baseline. It is shown that the total number of flights required for station assembly can be reduced, assuming both nominal Space Shuttle capacity, as well as Advanced Solid Rocket Motor capability. Baseline module requirements regarding crew size and rack accommodation are preserved. Considering the criteria listed above and current weight estimates, a six module option appears optimal. The resulting common module is 28 feet in length, and, in addition to two end cones, contains three radial ports near one end, which allows for a racetrack configuration pattern. This pattern exhibits several desirable attributes, including dual egress capability from any U.S. module, logical functional allocation distribution, no adverse impact to international partner accommodation, and favorable air lock, cupola, Assured Crew Return Vehicle, and logistics module accommodation

Utilization of common pressurized modules on the Space Station Freedom

During the preliminary design review of Space Station Freedom elements and subsystems, it was shown that reductions of cost, weight, and on-orbit integration and verification would be necessary in order to meet program constraints, particularly nominal Orbiter payload launch capability. At that time, the Baseline station consisted of four resource nodes and two 44 ft modules. In this study, the viability of a common module which maintains crew and payload accommodation is assessed. The size, transportation, and orientation of modules and the accommodation of system racks and user experiments are considered and compared to baseline. Based on available weight estimates, a module pattern consisting of six 28 ft. common elements with three radial and two end ports is shown to be nearly optimal. Advantageous characteristics include a reduction in assembly flights, dual egress from all elements, logical functional allocation, no adverse impacts to international partners, favorable airlock, cupola, ACRV (Assured Crew Return Vehicle), and logistics module accommodation, and desirable flight attitude and control characteristics

A study of concept options for the evolution of Space Station Freedom

Two conceptual evolution configurations for Space Station Freedom, a research and development configuration, and a transportation node configuration are described and analyzed. Results of pertinent analyses of mass properties, attitude control, microgravity, orbit lifetime, and reboost requirements are provided along with a description of these analyses. Also provided are brief descriptions of the elements and systems that comprise these conceptual configurations

Clinical and cost-effectiveness of a personalised health promotion intervention enabling independence in older people with mild frailty (‘HomeHealth’) compared to treatment as usual: study protocol for a randomised controlled trial

Background: Frailty is clinically associated with multiple adverse outcomes, including reduced quality of life and functioning, falls, hospitalisations, moves to long-term care and mortality. Health services commonly focus on the frailest, with highest levels of need. However, evidence suggests that frailty is likely to be more reversible in people who are less frail. Evidence is emerging on what interventions may help prevent or reduce frailty, such as resistance exercises and multi-component interventions, but few interventions are based on behaviour change theory. There is little evidence of cost-effectiveness. Previously, we co-designed a new behaviour change health promotion intervention (“HomeHealth”) to support people with mild frailty. HomeHealth is delivered by trained voluntary sector support workers over six months who support older people to work on self-identified goals to maintain their independence, such as strength and balance exercises, nutrition, mood and enhancing social engagement. The service was well received in our feasibility randomised controlled trial and showed promising effects upon outcomes. Aim: To test the clinical and cost-effectiveness of the HomeHealth intervention on maintaining independence in older people with mild frailty in comparison to treatment as usual (TAU). Methods: Single-blind individually randomised controlled trial comparing the HomeHealth intervention to TAU. We will recruit 386 participants from general practices and the community across three English regions. Participants are included if they are community-dwelling, aged 65 + , with mild frailty according to the Clinical Frailty Scale. Participants will be randomised 1:1 to receive HomeHealth or TAU for 6 months. The primary outcome is independence in activities of daily living (modified Barthel Index) at 12 months. Secondary outcomes include instrumental activities of daily living, quality of life, frailty, wellbeing, psychological distress, loneliness, cognition, capability, falls, carer burden, service use, costs and mortality. Outcomes will be analysed using linear mixed models, controlling for baseline Barthel score and site. A health economic analysis and embedded mixed-methods process evaluation will be conducted. Discussion: This trial will provide definitive evidence on the effectiveness and cost-effectiveness of a home-based, individualised intervention to maintain independence in older people with mild frailty in comparison to TAU, that could be implemented at scale if effective. Trial registration: ISRCTN, ISRCTN54268283. Registered 06/04/2020

Enabling health and maintaining independence for older people at home (HomeHealth trial): a multicentre randomised controlled trial.

BACKGROUND: NHS frailty services commonly target more severely frail older people, despite evidence suggesting frailty can be prevented or reversed when addressed at an earlier stage. HomeHealth is a new home-based, manualised voluntary sector service supporting older people with mild frailty to maintain their independence through behaviour change. Over six appointments, a trained HomeHealth worker discusses what matters to the older person and supports them to set and achieve goals around mobility, nutrition, socialising and/or psychological wellbeing. The service showed promising effects in a feasibility trial. We aimed to test the clinical and cost-effectiveness of HomeHealth for maintaining independence in older people with mild frailty compared with treatment as usual. METHODS: In this single-blind multicentre randomised controlled trial, we recruited community-dwelling older people aged 65 years or older with mild frailty from 27 general practices, community groups and sheltered housing in London, Yorkshire, and Hertfordshire. Participants were randomly assigned (1:1) to receive either HomeHealth monthly for 6 months or treatment as usual (usual GP and outpatient care, no specific frailty services). Our primary outcome was independence in activities of daily living, measured by blinded outcome assessors using the modified Barthel Index, and analysed using linear mixed models, including 6-month and 12-month data and controlling for baseline Barthel score and site. The study was approved by the Social Care Research Ethics Committee, and all participants provided written or orally recorded informed consent. This study is registered with the ISRCTN registry, ISRCTN54268283. FINDINGS: This trial took place between Jan 18, 2021, and July 4, 2023. We recruited 388 participants (mean age 81·4 years; 64% female [n=250], 94% White British/European [n=364], 2·5% Asian [n=10], 1·5% Black [n=6], 2·0% other [n=8]). We achieved high retention for 6-month follow-up (89%, 345/388), 12-month follow-up (86%, 334/388), and medical notes data (89%, 347/388). 182 (93%) of 195 participants in the intervention group completed the intervention, attending a mean of 5·6 appointments. HomeHealth had no effect on Barthel Index scores at 12 months (mean difference 0·250, 95% CI -0·932 to 1·432). At 6 months, there was a small reduction in psychological distress (-1·237, -2·127 to -0·348) and frailty (-0·124, -0·232 to -0·017), and at 12 months, we found small positive effects on wellbeing (1·449, 0·124 to 2·775) in those receiving HomeHealth. Other outcomes in analysis to date showed no significant difference. Health economic outcomes (including quality of life, capability, health services use and care needs or burden) are pending. INTERPRETATION: This high-quality trial showed that HomeHealth did not maintain independence in older people with mild frailty, and had limited effects upon secondary outcomes. Future studies need to explore different ways to promote health in this population. FUNDING: National Institute for Health and Care Research Health Technology Assessment (NIHR HTA)

Clinical interventions for venous leg ulcers: Proposals to improve the quality of clinical leg ulcer research

The present status of clinical leg ulcer healing research was reviewed by 25 experts over 2 days on September 28 and 29, 2015. Multiple clinical effectiveness reviews were presented suggesting that published clinical wound healing research often does not meet present (2015) evidence based standards. Specific areas requiring remediation were highlighted and approaches to overcoming existing challenges were proposed. Participants using anonymous voting technology developed an action plan to resolve perceived deficiencies. Statements were accepted if 75% of participants agreed. Older patients with a high frequency of comorbid conditions posed particular difficulties in designing clinical research protocols and better diagnostic categorization is necessary A standardized model template for collecting information about diagnosis and evaluation of the effect of interventions on healing of all types of leg ulcers was considered a high priority. Such a model template could be modified depending on the specific etiology of the leg ulcers. Generally agreed on quantifiable standards to establish degree of morbidity was considered a high priority. There was universal agreement that sources of funding and conflicts of interest needed to be disclosed in presentations and all publications. All clinical research studies should be registered with appropriate authorities. There was substantial enthusiasm for a clinical research network with quality standards for membership and an advisory research core available to investigators. Such a network should be funded and actively managed to insure long‐term viability. The governance of such an entity needs to be established by the wound care community. The present trend to integrate patients into the clinical research process was endorsed and there was enthusiasm to develop patient advocacy for wound healing research