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Smith, Brandon

Publications and source records attributed to Smith, Brandon.

Pterodactyl: Integrated Control Design for Precision Targeting of Deployable Entry Vehicles

Deployable Entry Vehicles (DEVs) enable in-situ scientific exploration at destinations with atmospheres across the solar system. Because they stow in a compact form and deploy only when ready to enter the atmosphere, DEVs relax the volume constraint imposed by rigid aeroshells. This work seeks to do for a DEV what the Wright Brothers did to propel modern day aviation: develop the guidance and control (G&C) methods that will make maneuvering and precision landing of DEV a reality. The Pterodactyl project objective is to deliver an integrated G&C methodology for a DEV, based on a detailed analysis that utilizes a Multi-disciplinary, Design, Analysis and Optimization (MDAO) framework. The current state-of-the-art for blunt body entry, G&C is rooted in the precision landing of vehicles such as Mars Science Laboratory (MSL) and Apollo, which used a propulsive reaction control system (RCS) to steer. Recent research has taken a particular interest in non-propulsive control for DEVs, including direct force control (angle of attack modulation via control surfaces or mass movement) and drag modulation (discrete change in ballistic coefficient). Using the MDAO framework that includes a guidance and control model to explore multiple control concepts for a DEV will shed light on the best design approach for these vehicles. In Pterodactyl, we will complete this study for a novel DEV concept, and then we will fabricate a functional prototype to help validate the design. The project is expected to down-select to a final control architecture by the end of 2018, and complete fabrication of the prototype by the end of 2019.The DEV chosen for detailed study in this project is the Adaptable Deployable Entry and Placement Technology (ADEPT). ADEPT uses a revolutionary 3D-woven carbon fabric that is foldable, can serve as primary structure, and can survive the extreme heating environment of atmospheric entry. The specific configuration of ADEPT under investigation is called Lifting Nano-ADEPT (LNA). LNA is designed for secondary payloads missions that require precision landing either for scientific objectives at a target destination or for payload recovery at Earth.The MDAO framework being created through this research, called COBRA-Pt (Composite Beam Roll-Up Solar Array-Prototype), will combine three critical elements of the system design: a guidance algorithm with Monte Carlo, a parametric control model, and vehicle geometry details. Novel control models being studied are deployable aerodynamic surfaces as well as shape morphing. These concepts will be compared at the system level with a more traditional propulsive RCS by comparing several key performance parameters. Upon completion of the design study, a functional prototype of LNA will be fabricated that will include the integration of guidance software and relevant control actuators. We expect this study will provide critical data that could feed into the development of an Earth-based flight test of LNA. The COBRA-Pt framework will provide a modular system by which to study any DEV concept in any atmosphere.

Smith, Brandon

The HIAD Orbital Flight Demonstration Instrumentation Suite

NASA's Hypersonic Inflatable Aerodynamic Decelerator (HIAD) technology has been selected for a Technology Demonstration Mission under the Science and Technology Mission Directorate. HIADs are an enabling technology that can facilitate atmospheric entry of heavy payloads to planets such as Earth and Mars using a deployable aeroshell. The deployable nature of the HIAD technology allows it to overcome the size constraints imposed on current rigid aeroshell entry systems. This permits use of larger aeroshells resulting in increased entry system performance (e.g. higher payload mass and/or volume, higher landing altitude at Mars). The Low Earth Orbit Flight Test of an Inflatable Decelerator (LOFTID) is currently scheduled for mid-2021. LOFTID will be launched out of Vandenberg Air Force Base as a secondary payload on an expendable launch vehicle. The flight test will employ a 6m diameter, 70-deg sphere-cone aeroshell and will provide invaluable high-energy orbital re-entry flight data. This data will be essential in supporting the HIAD team to mature the technology to diameters of 10m and greater. Aeroshells of this scale will address near-term commercial applications and potential future NASA missions.LOFTID will incorporate an extensive instrumentation suite totaling over 150 science measurements. This will include thermocouples, heat flux sensors, IR cameras, and a radiometer to characterize the aeroheating environment and aeroshell thermal response. An inertial measurement unit (IMU), GPS, and flush air data system will be included in order to reconstruct the flown trajectory and aerodynamic characteristics. Loadcells will be used to measure the HIAD structural loading, and HD cameras will be mounted on the aft segment looking at the aeroshell to monitor structural response. In addition to the primary instrumentation suite, a new fiber optic sensing system will be used to measure nose temperatures as a technology demonstration. The LOFTID instrumentation suites leverages Agency-wide expertise, with hardware development occurring at Ames Research Center, Langley Research Center, Marshall Space Flight Center and Armstrong Flight Research Center.This presentation will discuss the measurement objectives for the LOFTID mission, and the extensive instrumentation suite that has been selected to capture the HIAD's performance during the high-energy orbital re-entry flight test.

Swanson, Greg

ADEPT SR-1 Development and Testing

The Adaptable Deployable Entry and Placement Technology (ADEPT) Sounding Rocket One (SR-1) fight test will be the first sub-orbital flight of Nano-ADEPT. Nano-ADEPT is a deployable heatshield for secondary payload missions desiring to re-enter the Earth's atmosphere or deliver small science payloads to Mars or Venus. Two units have been built and tested in preparation of launch: one designated the "Spare" unit and one the "Flight" unit. The general development approach has been to perform all procedures on the Spare prior to performing them on Flight. This approach has served the project well, allowing for procedures to be rapidly developed and tested on spare hardware where mistakes are less consequential. Conversely, when schedule constraints have come up, the approach has allowed the project to rapidly pivot to an approach where Flight drives the critical path rather than Spare. This approach has enabled relatively rapid development of Flight where technical risk is balanced with schedule realism. This presentation will describe the various tests that have been performed on Nano-ADEPT Spare and Flight units to prepare for the sub-orbital flight. The purpose is to communicate the development approach we took for this low-cost, moderate-risk flight test and hopefully engage the EDL community in a wider discussion of risk-balanced approaches toward flight hardware development of secondary payload atmospheric entry systems.

Smith, Brandon

Entry at Venus

This is lecture to be given at the IPPW 2016, as part of the 2 day course on Short Course on Destination Venus: Science, Technology and Mission Architectures. The attached presentation material is intended to be introduction to entry aspects of Venus in-situ robotic missions. The presentation introduces the audience to the aerodynamic and aerothermodynamic aspects as well as the loads, both aero and thermal, generated during entry. The course touches upon the system design aspects such as TPS design and both high and low ballistic coefficient entry system concepts that allow the science payload to be protected from the extreme entry environment and yet meet the mission objectives.

Thermal protection

Nano-ADEPT Aeroloads Wind Tunnel Test

A wind tunnel test of the Adaptable Deployable Entry and Placement Technology (ADEPT) was conducted in April 2015 at the US Army's 7 by10 Foot Wind Tunnel located at NASA Ames Research Center. Key geometric features of the fabric test article were a 0.7 meter deployed base diameter, a 70 degree half-angle forebody cone angle, eight ribs, and a nose-to-base radius ratio of 0.7. The primary objective of this wind tunnel test was to obtain static deflected shape and pressure distributions while varying pretension at dynamic pressures and angles of attack relevant to entry conditions at Earth, Mars, and Venus. Other objectives included obtaining aerodynamic force and moment data and determining the presence and magnitude of any dynamic aeroelastic behavior (buzz/flutter) in the fabric trailing edge. All instrumentation systems worked as planned and a rich data set was obtained. This paper describes the test articles, instrumentation systems, data products, and test results. Four notable conclusions are drawn. First, test data support adopting a pre-tension lower bound of 10 foot pounds per inch for Nano-ADEPT mission applications in order to minimize the impact of static deflection. Second, test results indicate that the fabric conditioning process needs to be reevaluated. Third, no flutter/buzz of the fabric was observed for any test condition and should also not occur at hypersonic speeds. Fourth, translating one of the gores caused ADEPT to generate lift without the need for a center of gravity offset. At hypersonic speeds, the lift generated by actuating ADEPT gores could be used for vehicle control.

system engineering

Ames Infusion Stories for NASA Annual Technology Report

These are short (2-page) high-level summaries of technologies that have been infused - i.e., taken the next level. For example, 3DMAT started off as a Center Innovation Fund (CIF) project and graduated to the Game-changing Program (GCD), where it is being prepared for use in Orion. The Nano Entry System similarly started as CIF and graduated to GCD. The High Tortuosity Carbon Dioxide Conversion Device also started off as CIF and then received an award for further development from the NASA Innovative Advanced Concepts program (NIAC).

Smith, Brandon

Ames Infusion Stories for NASA Annual Technology Report: Nano Entry System for CubeSat-Class Payloads

The Nano Entry System for CubeSat-Class Payloads led to the development of the Nano-Adaptable Deployable Entry and Placement Technology ("Nano-ADEPT"). Nano-ADEPT is a mechanically deployed entry, descent, and landing (EDL) system that stows during launch and cruise (like an umbrella) and serves as both heat shield and primary structure during EDL. It is especially designed for small spacecraft where volume is a limiting constraint.

Smith, Brandon

Ames Infusion Stories for NASA Annual Technology Report: Development of an Ablative 3D Quartz / Cyanate Ester Composite Multi-Functional Material for the Orion Spacecraft Compression Pad

Vehicles re-entering Earth's atmosphere require protection from the heat of atmospheric friction. The Orion Multi-Purpose Crew Vehicle (MPCV) has more demanding thermal protection system (TPS) requirements than the Low Earth Orbit (LEO) missions, especially in regions where the structural load passes through. The use of 2-dimensional laminate materials along with a metal insert, used in EFT1 flight test for the compression pad region, are deemed adequate but cannot be extended for Lunar return missions.

Smith, Brandon

Sensors for Ablative Thermal Protection Systems

This is a chart for the NASA Ames Instrumentation Workshop scheduled for 16-Sept-2015. The workshop template was used to make the chart. The purpose is to communicate STAR lab capabilities to the larger Ames instrumentation community.

atmospheric entry

Nano-ADEPT Aeroloads Wind Tunnel Test

Analysis completed since the test suggests that all test objectives were met– This claim will be verified in the coming weeks as the data is examined further– Final disposition of test objective success will be documented in a final reportsubmitted to NASA stakeholders (early August 2015)– Expect conference paper in early 2016• Data products and observations made during testing will be used to refinecomputational models of Nano-ADEPT• Carbon fabric relaxed from its pre-test state during the test– System-level tolerance for relaxation will be driven by destination-specific andmission-specific aerothermal and aerodynamic requirements• Bonus experiment of asymmetric shape demonstrates that an asymmetricdeployable blunt body can be used to generate measureable lift– With a strut actuation system and a robust GN&C algorithm, this effect could beused to steer a blunt body at hypersonic speeds to aid precision landing

atmospheric entry

Enabling Venus In-Situ Science - Deployable Entry System Technology, Adaptive Deployable Entry and Placement Technology (ADEPT): A Technology Development Project funded by Game Changing Development Program of the Space Technology Program

Venus is one of the important planetary destinations for scientific exploration, but: The combination of extreme entry environment coupled with extreme surface conditions have made mission planning and proposal efforts very challenging. We present an alternate, game-changing approach (ADEPT) where a novel entry system architecture enables more benign entry conditions and this allows for greater flexibility and lower risk in mission design

Wercinski, Paul F.

Mission Sizing and Trade Studies for Low Ballistic Coefficient Entry Systems to Venus

The U.S and the U.S.S.R. have sent seventeen successful atmospheric entry missions to Venus. Past missions to Venus have utilized rigid aeroshell systems for entry. This rigid aeroshell paradigm sets performance limitations since the size of the entry vehicle is constrained by the fairing diameter of the launch vehicle. This has limited ballistic coefficients (beta) to well above 100 kg/m2 for the entry vehicles. In order to maximize the science payload and minimize the Thermal Protection System (TPS) mass, these missions have entered at very steep entry flight path angles (gamma). Due to Venus thick atmosphere and the steep-gamma, high- conditions, these entry vehicles have been exposed to very high heat flux, very high pressures and extreme decelerations (upwards of 100 g's). Deployable aeroshells avoid the launch vehicle fairing diameter constraint by expanding to a larger diameter after the launch. Due to the potentially larger wetted area, deployable aeroshells achieve lower ballistic coefficients (well below 100 kg/m2), and if they are flown at shallower flight path angles, the entry vehicle can access trajectories with far lower decelerations (~50-60 g's), peak heat fluxes (~400 W/cm2) and peak pressures. The structural and TPS mass of the shallow-gamma, low-beta deployables are lower than their steep-gamma, high-beta rigid aeroshell counterparts at larger diameters, contributing to lower areal densities and potentially higher payload mass fractions. For example, at large diameters, deployables may attain aeroshell areal densities of 10 kg/m2 as opposed to 50 kg/m2 for rigid aeroshells. However, the low-beta, shallow-gamma paradigm also raises issues, such as the possibility of skip-out during entry. The shallow-gamma could also increase the landing footprint of the vehicle. Furthermore, the deployable entry systems may be flexible, so there could be fluid-structure interaction, especially in the high altitude, low-density regimes. The need for precision in guidance, navigation and control during entry also has to be better understood. This paper investigates some of the challenges facing the design of a shallow-gamma, low-beta entry system.

Dutta, Soumyo

Yamato: Bringing the Moon to the Earth ... Again

The Yamato mission to the lunar South Pole-Aitken Basin returns samples that enable dating of lunar formation and the lunar bombardment period. The design of the Yamato mission is based on a systems engineering process which takes an advanced consideration of cost and mission risk to give the mission a high probability of success.

Lam, King