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Dwyer Cianciolo, Alicia

Publications and source records attributed to Dwyer Cianciolo, Alicia.

16 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2020

Strategic Implications of Phobos as a Staging Point for Mars Surface Missions

As human exploration endeavors begin to set sights beyond low Earth orbit to the surface of the Moon, exploration of the surface of Mars continues to serve as the “horizon destination” to help focus development and research efforts. One Mars exploration strategy often discussed is the notion of utilizing the moons of Mars, namely Phobos, as an exploration destination prior to Mars surface missions. The premise behind this is that staging missions from Mars’ moons as well as exploring the moons themselves would be less costly and risky. However, understanding potential advantages of Phobos staging and exploration must be done in the context of the overall end-to-end Mars surface exploration needs, goals, objectives, campaign approach, and systems required. This paper examines the strategic implications of utilizing the moons of Mars as a potential location for exploration of Mars. Operational concepts utilizing both Phobos and Mars orbital strategies will be examined to understand the architectural impacts of this staging strategy. The strategic implications of each operational concept are assessed to determine the overall key challenges and strategic links to other exploration destinations. Results from this analysis indicate that, if the objective is to conduct Mars surface missions, utilizing Phobos as an exploration destination adds little benefit toward the goal of exploration of Mars.

Drake, Bret G.↗
NASA NTRS2019

Human Mars Entry, Descent and Landing Architecture Study: Deployable Decelerators

NASA’s Entry, Descent and Landing Architecture Study uses a trajectory simulation framework to evaluate various technologies and concepts of operations for human scale EDL at Mars. The study results inform agency technology investments. This paper summarizes the design assumptions and analysis of two deployable entry concepts performed in Phase 2 of the study. The entry concepts include a rigid deployable called the Adaptable Deployable Entry Placement Technology and an inflatable concept called the Hypersonic Inflatable Aerodynamic Decelerator. This paper describes the concept operations of these vehicles to deliver a 20-metric ton payload to the surface of Mars. Details of vehicle design and flight performance are summarized along with results of analysis on the aft body heating and its effect on the payload. Finally, recommended technology investments based on the results are presented.

Dwyer Cianciolo, Alicia↗
NASA NTRS2019

PL&HA and SPLICE Overview

Guidance, Navigation and Control (GN&C) technologies for precise and safe landing are essential for future robotic science and human exploration missions to solar system destinations with targeted surface locations that pose a significant risk to successful landing and subsequent mission operations. These Entry, Descent and Landing (EDL) technologies are a part of the NASA domain called PL&HA (Precision Landing and Hazard Avoidance) and are considered high priority capabilities within the space technology roadmaps from NASA and the National Research Council (NRC). The PL&HA technologies promote and enable new missions concepts to solar system destinations.

Precision Landing and Hazard Avoidance (PL&HA)↗
NASA NTRS2019

Defining Navigation Requirements for Future Precision Lander Missions

Human mission concepts for both the Moon and Mars require landing precision capabilities beyond the current state of art. The Safe and Precise Landing Integrated Capabilities Evolution (SPLICE) project leverages previous work at NASA to develop multimission precision landing and hazard avoidance (PL&HA) technologies to meet the advanced landing requirements. SPLICE aims to develop guidance, navigation and control (GN&C) capabilities for both Moon and Mars lander missions. The approach the project is using to identify a standard suite begins with developing a PL&HA requirements matrix to inform technology investments. The approach to develop a multi-mission navigation requirements matrix includes identifying representative concepts of operations for both robotic and human missions. It also identifies navigation sensor options with estimated performance parameters. This paper summarizes the concepts of operations and sensors considered to develop the SPLICE PL&HA requirements matrix. A description of the analysis used to determine candidate optimal sensor suites and initial results are provided.

Dwyer Cianciolo, Alicia↗
NASA NTRS2018

Human Mars Entry, Descent and Landing Architecture Study (EDLAS): Rigid Decelerators

Develop two evolutionary rigid vehicle concepts to deliver human-scale payloads (20 metric tons) to the surface of Mars: Capsule; Lifting body, mid-range lift-to-drag ratio (Mid L/D). Determine vehicle configurations for various mission flight phases. Determine vehicle performance: Integrated system mass; Ability to meet landing constraints; Payload packaging and surface access. Provide technology investment recommendations to NASA’s Space Technology Mission Directorate.

Polsgrove, Tara↗
NASA NTRS2018

New Efforts to Update NASA's Global Reference Atmospheric Models (GRAM)

NASA is at the forefront of planetary exploration. The inability to test planetary spacecraft in the flight environment prior to a mission requires engineers to rely on ground-based testing and models of the vehicle and expected environments. One of the most widely used engineering models of the atmosphere for many NASA projects is the Global Reference Atmospheric Model (GRAM) developed by the NASA Marshall Space Flight Center (MSFC). Over the past decade GRAM upgrades and maintenance have depended on inconsistent and waning project-specific support. Recently, the NASA Science Mission Directorate agreed to provide funding support in Fiscal Year 2018 and 2019 to upgrade the GRAMs. This poster summarizes the objectives, tasks and milestones of this effort.

Justh, Hilary↗
NASA NTRS2018

New Efforts to Update NASA's Global Reference Atmospheric Models (GRAM)

NASA is at the forefront of planetary exploration. The inability to test planetary spacecraft in the flight environment prior to a mission requires engineers to rely on ground-based testing and models of the vehicle and expected environments. One of the most widely used engineering models of the atmosphere for many NASA projects is the Global Reference Atmospheric Model (GRAM) developed by the NASA Marshall Space Flight Center (MSFC). Over the past decade GRAM upgrades and maintenance have depended on inconsistent and waning project-specific support. Recently, the NASA Science Mission Directorate agreed to provide funding support in Fiscal Year 2018 and 2019 to upgrade the GRAMs. This poster summarizes the objectives, tasks and milestones of this effort.

Dwyer Cianciolo, Alicia↗
NASA NTRS2017

Impacts of Launch Vehicle Fairing Size on Human Exploration Architectures

Human missions to Mars, particularly to the Martian surface, are grand endeavors that place extensive demands on ground infrastructure, launch capabilities, and mission systems. The interplay of capabilities and limitations among these areas can have significant impacts on the costs and ability to conduct Mars missions and campaigns. From a mission and campaign perspective, decisions that affect element designs, including those based on launch vehicle and ground considerations, can create effects that ripple through all phases of the mission and have significant impact on the overall campaign. These effects result in impacts to element designs and performance, launch and surface manifesting, and mission operations. In current Evolvable Mars Campaign concepts, the NASA Space Launch System (SLS) is the primary launch vehicle for delivering crew and payloads to cis-lunar space. SLS is currently developing an 8.4m diameter cargo fairing, with a planned upgrade to a 10m diameter fairing in the future. Fairing diameter is a driving factor that impacts many aspects of system design, vehicle performance, and operational concepts. It creates a ripple effect that influences all aspects of a Mars mission, including: element designs, grounds operations, launch vehicle design, payload packaging on the lander, launch vehicle adapter design to meet structural launch requirements, control and thermal protection during entry and descent at Mars, landing stability, and surface operations. Analyses have been performed in each of these areas to assess and, where possible, quantify the impacts of fairing diameter selection on all aspects of a Mars mission. Several potential impacts of launch fairing diameter selection are identified in each of these areas, along with changes to system designs that result. Solutions for addressing these impacts generally result in increased systems mass and propellant needs, which can further exacerbate packaging and flight challenges. This paper presents the results of the analyses performed, the potential changes to mission architectures and campaigns that result, and the general trends that are more broadly applicable to any element design or mission planning for human exploration.

Jefferies, Sharon↗
NASA NTRS2017

Mission and Design Sensitivities for Human Mars Landers Using Hypersonic Inflatable Aerodynamic Decelerators

Landing humans on Mars is one of NASA's long term goals. The Evolvable Mars Campaign (EMC) is focused on evaluating architectural trade options to define the capabilities and elements needed for a sustainable human presence on the surface of Mars. The EMC study teams have considered a variety of in-space propulsion options and surface mission options. As we seek to better understand how these choices affect the performance of the lander, this work informs and influences requirements for transportation systems to deliver the landers to Mars and enable these missions. This paper presents the effects of mission and vehicle design options on lander mass and performance. Beginning with Earth launch, options include fairing size assumptions, co-manifesting other elements with the lander, and Earth-Moon vicinity operations. Capturing into Mars orbit using either aerocapture or propulsive capture is assessed. For entry, descent, and landing both storable as well as oxygen and methane propellant combinations are considered, engine thrust level is assessed, and sensitivity to landed payload mass is presented. This paper focuses on lander designs using the Hypersonic Inflatable Aerodynamic Decelerators (HIAD), one of several entry system technologies currently considered for human missions.

Polsgrove, Tara P.↗
NASA NTRS2017

Entry, Descent, and Landing Guidance and Control Approaches to Satisfy Mars Human Mission Landing Criteria

Precision landing on Mars is a challenge. All Mars lander missions prior to the 2012 Mars Science Laboratory (MSL) had landing location uncertainty ellipses on the order of hundreds of kilometers. Sending humans to the surface of Mars will likely require multiple landers delivered in close proximity, which will in turn require orders of magnitude improvement in landing accuracy. MSL was the first Mars mission to use an Apollo-derived bank angle guidance to reduce the size of the landing ellipse. It utilized commanded bank angle magnitude to control total range and bank angle reversals to control cross range. A shortcoming of this bank angle guidance is that the open loop phase of flight created by use of bank reversals increases targeting errors. This paper presents a comparison of entry, descent and landing performance for a vehicle with a low lift-to-drag ratio using both bank angle control and an alternative guidance called Direct Force Control (DFC). DFC eliminates the open loop flight errors by directly controlling two forces independently, lift and side force. This permits independent control of down range and cross range. Performance results, evaluated using the Program to Optimize Simulated Trajectories (POST2), including propellant use and landing accuracy, are presented.

Dwyer Cianciolo, Alicia↗
NASA NTRS2016

Human Mars Entry, Descent and Landing Architectures Study Overview

Landing humans on Mars will require entry, descent and landing (EDL) capability beyond the current state of the art. Nearly twenty times more delivered payload and an order of magnitude improvement in precision landing capability will be necessary. Several EDL technologies capable of meeting the human class payload delivery requirements are being considered. The EDL technologies considered include low lift-to-drag vehicles like Hypersonic Inflatable Aerodynamic Decelerators (HIAD), Adaptable Deployable Entry and Placement Technology (ADEPT), and mid range lift-to-drag vehicles like rigid aeroshell configurations. To better assess EDL technology options and sensitivities to future human mission design variations, a series of design studies has been conducted. The design studies incorporate EDL technologies with conceptual payload arrangements defined by the Evolvable Mars Campaign to evaluate the integrated system with higher fidelity than have been performed to date. This paper describes the results of the design studies for a lander design using the HIAD, ADEPT and rigid shell entry technologies and includes system and subsystem design details including mass and power estimates. This paper will review the point design for three entry configurations capable of delivering a 20 t human class payload to the surface of Mars.

Polsgrove, Tara T.↗
NASA NTRS2015

Intercomparison of Martian Lower Atmosphere Simulated Using Different Planetary Boundary Layer Parameterization Schemes

We use the mesoscale modeling capability of Mars Weather Research and Forecasting (MarsWRF) model to study the sensitivity of the simulated Martian lower atmosphere to differences in the parameterization of the planetary boundary layer (PBL). Characterization of the Martian atmosphere and realistic representation of processes such as mixing of tracers like dust depend on how well the model reproduces the evolution of the PBL structure. MarsWRF is based on the NCAR WRF model and it retains some of the PBL schemes available in the earth version. Published studies have examined the performance of different PBL schemes in NCAR WRF with the help of observations. Currently such assessments are not feasible for Martian atmospheric models due to lack of observations. It is of interest though to study the sensitivity of the model to PBL parameterization. Typically, for standard Martian atmospheric simulations, we have used the Medium Range Forecast (MRF) PBL scheme, which considers a correction term to the vertical gradients to incorporate nonlocal effects. For this study, we have also used two other parameterizations, a non-local closure scheme called Yonsei University (YSU) PBL scheme and a turbulent kinetic energy closure scheme called Mellor- Yamada-Janjic (MYJ) PBL scheme. We will present intercomparisons of the near surface temperature profiles, boundary layer heights, and wind obtained from the different simulations. We plan to use available temperature observations from Mini TES instrument onboard the rovers Spirit and Opportunity in evaluating the model results.

Natarajan, Murali↗
NASA NTRS2014

International Space Station (ISS) External Thermal Control System (ETCS) Loop A Pump Module (PM) Jettison Options Assessment

On December 11, 2013, the International Space Station (ISS) experienced a failure of the External Thermal Control System (ETCS) Loop A Pump Module (PM). To minimize the number of extravehicular activities (EVA) required to replace the PM, jettisoning the faulty pump was evaluated. The objective of this study was to independently evaluate the jettison options considered by the ISS Trajectory Operations Officer (TOPO) and to provide recommendations for safe jettison of the ETCS Loop A PM. The simulation selected to evaluate the TOPO options was the NASA Engineering and Safety Center's (NESC) version of Program to Optimize Simulated Trajectories II (POST2) developed to support another NESC assessment. The objective of the jettison analysis was twofold: (1) to independently verify TOPO posigrade and retrograde jettison results, and (2) to determine jettison guidelines based on additional sensitivity, trade study, and Monte Carlo (MC) analysis that would prevent PM recontact. Recontact in this study designates a propagated PM trajectory that comes within 500 m of the ISS propagated trajectory. An additional simulation using Systems Tool Kit (STK) was run for independent verification of the POST2 simulation results. Ultimately, the ISS Program removed the PM jettison option from consideration. However, prior to the Program decision, the retrograde jettison option remained part of the EVA contingency plan. The jettison analysis presented showed that, in addition to separation velocity/direction and the atmosphere conditions, the key variables in determining the time to recontact the ISS is highly dependent on the ballistic number (BN) difference between the object being jettisoned and the ISS.

Murri, Daniel G.↗
NASA NTRS2011

Passive Aerogravity Assisted Trajectories for a Mars Atmospheric Sample Return Mission

A number of studies have demonstrated that aerodynamic lift during a planetary low-altitude atmospheric flyby can increase the V(sub infinity) bending angle and the total delta V achievable from gravity assist. Aero-Gravity Assist (AGA) trajectories of this type require a significantly high spacecraft L/D (lift-to-drag) ratio and a fairly robust closed-loop guidance algorithm capable of providing a desired control authority for level, nearly constant-altitude atmospheric flight. The AGA concept has been described in some previous publications as one of the techniques for Mars and Venus atmospheric sample return mission design strategies. Recent analysis has demonstrated that passive, ballistic (zero-lift) aeropass trajectories could equally satisfy potential future sample return mission objectives and provide quite robust and simple alternatives to a complex guided AGA lifting trajectory design.

sample return missions↗