Implementing CubeSat Avionics Components to Full-Scale Capsule Return Missions

Returning samples from Low Earth Orbit (LEO) is no simple task. Whether the samples are scientific experiments or surveillance footage, engineers must overcome many challenges to achieve mission success. In August of 1960 the first payload recovered from LEO, the Corona capsule, carried more photographic coverage of the Soviet Union than all previous U-2 missions. The Corona program proved that re-turning surveillance footage from LEO is possible, the program is still referenced today when designing new sample return missions. Although there are many crucial subsystems that make up a sample return capsule, the avionics subsystem demands the most attention. This paper will discuss how current CubeSat avionics components can be applied to large sample return missions. One advantage of using CubeSat avionics components is that they can fit into a 1.5 U (10x10x15 cm) compartment, leaving more room for the payload. This paper is broken down as follows. First, the reader is introduced to the history of sample return projects. The major design strengths of previous projects are analyzed and applied to the current capsule design. Next, the typical trajectory of a capsule is presented along with mission requirements and operations. During the re-entry phase, the avionics subsystem is responsible for commanding the deployment of the parachute, back shell, and the heat shield. Next, the power subsystem is discussed in detail including a trade study on batteries and voltage regulators. Next, the interface between the Ground Support Equipment (GSE) and the avionics components is discussed. It is important that the capsule is able to provide avionics system state of health to ensure proper functionality before the capsule is launched. Next, an in-depth analysis of current TechEdSat avionics components, with proven flight history, are presented. The various avionics components including the radios, GPS, IMU, temperature sensors, altitude sensors, and ejectors are discussed. The application of cur-rent avionics components to a sample return projects are analyzed. After, the wiring diagram is presented along with a discussion of the design. Next, a summary of how the avionics components are tested and validated is pro-vided. Finally, this article will present current sample return missions TechEdSat avionics components are being applied to. CubeSat Avionics can be applied to almost all sample return missions due to their compact configuration and proven space flight heritage. The TechEdSat team is currently making great progress in returning samples from the International Space Station (ISS) and is excited to present how their avionics components can be applied to a full-scale sample return mission

Induced Anisotropies in NiCo Obliquely Deposited Films and Their effect on Magnetic Domains

English Article: Oblique and in-plane anisotropies in obliquely evaporated NiCo thin films were investigated in order to understand their origin. All the compositions studied clearly show the effect of columnar grain morphology coupled with some intrinsic factors such as magnetostriction and crystallinity. Energy calculations are undertaken to explain the effect of

The TechEdSat-N Series: A Collaborative Technology Development Platform in the Nano-Satellite Form Factor

The TechEdSat-1 (TES-1) was the first U.S. CubeSat to be deployed from the ISS (International Space Station). This permitted the initiation of a flight series that has recently de-orbited the 6th nano-satellite with subsequent numbers 7-10 under development. The nano-satellites range from 1U (1 unit) to 6U (TechEdSat-8) but have the critical ISS Safety design features standardized in order to focus on the particular experiment objectives. Incremental experimental development has included unique communication subsystems such as command/control of the nanosatellite through email commands -as well as a recent record for Wifi transmission. Also, the thermophysics of controlled drag devices (Exo-Brake) has been developed which will prelude sample return and planetary exploration applications. The successful "rapid incremental experiment" approach has also been incorporated into collaborations with academia, permitting professors/student interns to be exposed to the rigors of space mission hardware design and execution. The TechEdSat-8, a linear 6U configuration, allows for 5 different groups to contribute an "experiment, sensor, or sub-system" through a well-defined common interface. Lastly, the flying laboratory concept is helpful in developing future interplanetary nano-satellite subsystems which will advance exploration goals by allowing rapid demonstration/validation first in LEO (Low Earth Orbit)

BRAINSTACK – A Platform for Artificial Intelligence & Machine Learning Collaborative Experiments on a Nano-Satellite

Space missions have become more ambitious with exploration targets growing ever distant while simultaneously requiring larger guidance and communication budgets. These conflicting desires of distance and control drive the need for in-situ intelligent decision making to reduce communication and control limitations. While ground based research on Artificial Intelligence and Machine Learning (AI/ML) software modules has grown exponentially, the capacity to experimentally validate such software modules in space in a rapid and inexpensive format has not. To this end, the Nano Orbital Workshop (NOW) group at NASA Ames Research Center is performing flight evaluation tests of ‘commercially’ available bleeding-edge computational platforms via what is programmatically referred to as the BrainStack on the TechEdSat (TES-n) flight series. Processors selected as part of the BrainStack are of ideal size, packaging, and power consumption for easy integration into a cube satellite structure. These experiments have included the evaluation of small, high-performance GPUs and, more recently, neuromorphic processors in LEO operations. Additionally, it is planned to measure the radiation environment these processors experience to understand any degradation or computational artifacts caused by long term space radiation exposure on these novel architectures. This evolving flexible and collaborative environment involving various research teams across NASA and other organizations is intended to be a convenient orbital test platform from which many anticipated future space automation applications may be initially tested

Patient-specific RF safety assessment in MRI: Progress in creating surface-based human head and shoulder models

The interaction of electromagnetic (EM) fields with the human body during magnetic resonance imaging (MRI) is complex and subject specific. MRI radiofrequency (RF) coil performance and safety assessment typically includes numerical EM simulations with a set of human body models. The dimensions of mesh elements used for discretization of the EM simulation domain must be adequate for correct representation of the MRI coil elements, different types of human tissue, and wires and electrodes of additional devices. Examples of such devices include those used during electroencephalography, transcranial magnetic stimulation, and transcranial direct current stimulation, which record complementary information or manipulate brain states during MRI measurement. The electrical contact within and between tissues, as well as between an electrode and the skin, must also be preserved. These requirements can be fulfilled with anatomically correct surface-based human models and EM solvers based on unstructured meshes. Here, we report (i) our workflow used to generate the surface meshes of a head and torso model from the segmented AustinMan dataset, (ii) head and torso model mesh optimization for three-dimensional EM simulation in ANSYS HFSS, and (iii) several case studies of MRI RF coil performance and safety assessment

TES-8: Advanced Exo-Brake, VR and COM Experiments

The TES-8 was jettisoned from the International Space Station on January 31, 2019. As an orbital laboratory and 8th in on-going series, the design makes use of a standard set of interfaces and safety features that permit rapid re-flight. On this flight, an advanced Exo-Brake is flown with de-orbit targeting capability that will engender sample return capability from LEO platforms. A Virtual Reality data recording system uses stereo imaging and efficient data-compression with an NVIDIA GPU (Graphics Processing Unit) to permit compression and transmission of very large data files. An SDR (Software Defined Radio) will download data to the NEN (Near Earth Network) for the first time - demonstrating potential use in cis-lunar space using S-band. For the first time, a comparison will be made regarding the functionality of the Iridium and Globalstar short burst data modems - as essential communication tools for future nano-sat projects. Lastly, the 7 micro-processors and 4 cameras provide an excellent learning platform for university students and NASA young professionals

The Doppler Wind Temperature Sensor (DWTS) Flight Evaluation and Experiments (TES-16,17)

The Doppler Wind and Temperature Sounder instrument (DWTS) developed by Global Atmospheric Technologies and Sciences (GATS) is a simple yet powerful tool with the potential to become a new window through which the study of upper atmosphere dynamics can occur. Based around a defense-grade infrared camera peering through a static gas cell used as a scanning spectral filter, a DWTS instrument can infer wind velocities and kinetic temperatures throughout the stratosphere and lower thermosphere. The DWTS achieves this scanning by measuring the induced Doppler shift and Doppler broadening of emissions as they pass through the DWTS field of view (Gordley, Marshall, 2011). The DWTS holds promise in improving accuracy in weather determination among other terrestrial benefits, and the core technology can be easily adapted to study the dynamics of other planetary atmospheres. In partnership with GATS, NOAA, and other collaborators, NASA Ames and the Nano-Orbital Workshop (NOW) group have been working to evaluate the DWTS instrument on orbit and optimize it as a flexible payload for nanosatellites. The first mission selected for DWTS technical evaluation is preparing for flight in early 2024, which will be followed by a more capable science mission in 2025, with both missions being part of the TES-n/NOW heritage flight series. The first rapid technology demonstration flight, TES-16/DWTS-A, will demonstrate a single DWTS instrument in an approximately 2U payload volume. With an estimated power consumption of 50 watts, the instrument will maintain the imaging sensor plane at 80K during instrument performance evaluation periods using an integrated Stirling cryocooler. Data from DWTS will be captured and processed via a NOW-designed custom data interface unit before being transmitted via S-band radio back to select ground stations, with instrument command and control maintained via L-band global-coverage radio. The subsequent TES-17/DWTS-B mission will be a dedicated science mission tasked with validating the instrument’s full altitude coverage capabilities, currently estimated from 20 to 200 km during both day and night. This new atmospheric observational capability will come from a single small satellite equipped with three DWTS imagers, each hosting a different gas cell chemistry, to form a complete instrument. The intention of this flight series, and one of NASA’s interests in this instrument, is not only to advance Earth atmospheric dynamics, but to advance a Martian atmospheric study instrument as well (Colaprete, Gordley, et al) which, if successful, would greatly further understanding of Martian atmospheric dynamics. This document describes the flight series in detail, including challenges facing the TES-16 flight tests and the projected challenges and application of Mars study. Additional detail regarding the possible applications of a Cognitive Communication technique in current flight development by NOW collaborators at the NASA Glenn Research Center is also discussed, including the implications of using an automated User Initiated Service (UIS) protocol to maximize the data collected per orbit

Providing Small Satellite Communications Using the NOAA GOES Satellite

The results of a LEO to GEO communication system using the NOAA GOES (Geostationary Operational Environmental Satellite) DCS (Data Collection System) are presented. The DCS system was designed to collect climate-related data from remote unmanned stations. Data are uplinked to one of the two operational satellites via an aggregated link to the NASA Wallops Facility. The modified LEO transmitter, one of the 7 transmitters flown on the TechEdSat-8 nano-satellite, is designed to compensate for the Doppler effects to ensure the communication link. Though a slow data rate initially, the system may offer another convenient means of transmitting data from LEO to ground stations any time during an orbit. The experiment will allow for an assessment of this as a future communication system development path - as well as the very interesting extension of the system for a comparable system at Mars for climatic surveys from ground stations (hence, a Mars radio)

Modulated Exo-Brake Flight Testing - Modeling and Test Results - Successes with Exo-Brake Development and Targeting for Future Sample Return Capability: TES-6,7,8 Flight Experiments

No abstract availabl

Modeling the Exo-Brake and the Development of Strategies for De-Orbit Drag Modulation

The Exo-Brake is a simple, non-propulsive means of de-orbiting small payloads from orbital platforms such as the International Space Station (ISS). Two de-orbiting experiments with fixed surface area Exo-Brakes have been successfully conducted in the last two years on the TechEdSat-3 and -4 nano-satellite missions. The development of the free molecular flow aerodynamic data-base is presented in terms of angle of attack, projected front surface area variation, and altitude. Altitudes are considered ranging from the 400km ISS jettison altitude to 90km. Trajectory tools are then used to predict de-orbit/entry corridors with the inclusion of the key atmospheric and geomagnetic uncertainties. Control system strategies are discussed which will be applied to the next two planned TechEdSat-5 and -6 nano-satellite missions - thus increasing the targeting accuracy at the Von Karman altitude through the proposed drag modulation technique