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At least 181 records · Page 10

Command and Control System Software Development

Kennedy Space Center has been the heart of human space flight for decades. From the Apollo Program to the Space Shuttle Program, and now to the coming Space Launch System (SLS) and Orion, NASA will be a leader in deep space exploration for mankind. Before any rockets blast off, there is significant work to be done in preparation for launch. People working on all aspects of spaceflight must contribute by developing new technology that has yet to participate in a successful launch, and which can work with technology already proven in flight. These innovations, whether hardware or software, must be tried and true, and includes the projects to which interns contribute to. For this internship, the objective was to create a data recording system for the developers of a LCS section that records certain messages in the traffic of the system. Developers would then be able to use these recordings for analysis later on, either manually or by an automated test. The tool would be of convenience to a developer as it would be used if the system's main data recorder was not available for tests.

Velasquez, Ricky↗

Command and Control Software Development Memory Management

This internship was initially meant to cover the implementation of unit test automation for a NASA ground control project. As is often the case with large development projects, the scope and breadth of the internship changed. Instead, the internship focused on finding and correcting memory leaks and errors as reported by a COTS software product meant to track such issues. Memory leaks come in many different flavors and some of them are more benign than others. On the extreme end a program might be dynamically allocating memory and not correctly deallocating it when it is no longer in use. This is called a direct memory leak and in the worst case can use all the available memory and crash the program. If the leaks are small they may simply slow the program down which, in a safety critical system (a system for which a failure or design error can cause a risk to human life), is still unacceptable. The ground control system is managed in smaller sub-teams, referred to as CSCIs. The CSCI that this internship focused on is responsible for monitoring the health and status of the system. This team's software had several methods/modules that were leaking significant amounts of memory. Since most of the code in this system is safety-critical, correcting memory leaks is a necessity.

Programmin↗

Command and Control Software Development

As NASA’s role in spaceflight operations change, so too does its design priorities. NASA’s flagship venture, the Space Launch System (SLS), is being created primarily to explore deep space. While commercial partners conduct low Earth orbit resupplies, tests, and even transportation of astronauts, NASA can divert more resources to more exciting projects - going back to the moon, or onwards to Mars. In the short term, this goal manifests in the upcoming Exploration Mission-1 (EM-1) test of the SLS, slated for as early as 2019. SLS, with the Orion capsule, will travel farther than any human-rated spacecraft has gone before. As the most powerful launch vehicle ever created, SLS requires many new innovations to ensure mission success. One such technology is the launch control software, which is the focus of this internship. The SLS launch control software is composed of many functions, all of which require rigorous testing to meet the standard of life-critical code. To facilitate easier testing, the first project I undertook was to customize the open-source tool Wireshark to the software team’s needs. Wireshark is a network protocol analyzer that can take in information about custom information packets. The launch control software will have several protocols that are custom to NASA. I ensured that all necessary component files were the correct file type and in the correct structure for Wireshark to compile. Having allowed Wireshark access to understand custom NASA data packets, testers of the launch control software will be able to find anomalies easier.

Wang, Zhengdong↗

Spaceport Command and Control System Software Development

The control system for the Space Launch System (SLS) and Orion capsule contains a multitude of displays for use in displaying information like vehicle health, sensor information, life support, etc. Currently users in the Launch Control Center (LCC) are using a list-based selection Graphical User Interface (GUI) to open various displays. However the display names are not intuitive as to what the display looks like nor what data is presented in a display. My project involves adding additional functionality to the current display selection GUI utilizing thumbnail images of each display for easy browsing. This new GUI allows users to find their desired display much faster without needing to memorize the layout of every display based only on the display's name.

Chapa, Nicholas↗

FPGA-based hardware/software co-design instrument command-and-control solutions

Traditional design methodology dictates that an instrument electronics platform should consist of a printed circuit board (PCB)—often multiple boards—populated with many components and support electronics. More specifically, each subsystem is composed of numerous integrated circuits (ICs) spread across the board(s), connected with innumerable traces and wires. Additionally, it is often the case that the hardware and software design teams are quite separated—the hardware team designs a board and hands it to a software team, who must then deal with any hardware quirkiness and may need to rewrite software due to inadequately defined interfaces...

Allen, Mark A.↗

On-demand Command and Control of ASTERIA with Cloud-based Ground Station Services

ASTERIA (Arcsecond Space Telescope Enabling Research in Astrophysics) was a 6-unit CubeSat technology demonstration mission that deployed from the International Space Station on November 20th, 2017. After successfully completing its 90-day primary mission that demonstrated arcsecond-level line-of-sight pointing and focal plane thermal stability for exoplanet detection, it entered an extended mission performing onboard software demonstrations to mature technology both in space and on the ground. One of the technologies was a completely cloud-based ground system leveraging Amazon Web Services (AWS) Ground Station service.Announced in December 2018 and launched in May 2019, AWS Ground Station is a fully managed ground station service that aims to reduce the overhead associated with developing and maintaining ground system infrastructure throughout the mission lifecycle. AWS Ground Station makes available the suite of features required for any ground system in support of low-Earth orbit (LEO) and medium-Earth Orbit (MEO) satellite operations on-demand and without setting up or maintaining long-term contracts. Charges are incurred on a per-minute basis for antenna usage during scheduled tracks. Support is available for S-band uplink and downlink, along with X-band narrowband and wideband downlink. Missions that use the service may reserve tracks with any licensed AWS Ground Station antennas located across each service region and have direct access to any AWS services in support of mission operations.The cloud-based architecture built around the AWS Ground Station service greatly enhanced ASTERIA mission operations by enabling end-to-end pass automation, on-demand contact scheduling and contingency planning, along with more efficient data downlink through station availability and station-to-station handovers. It incorporated open-source software, particularly NASA's AMMOS Instrument Toolkit (AIT) and Open Mission Control Technologies (OpenMCT), along with the AWS application programming interfaces (API) to the Ground Station, Elastic Compute Cloud (EC2) and Simple Storage Service (S3) services. After showcasing operability in August 2019, the team continued using and improving this novel ground system architecture until the end of mission in December 2019. This paper describes the cloud-based ground system, how it was designed, tested, and evaluated with an in-orbit spacecraft, the operational capabilities that it enabled, along with lessons learned and recommendations for future missions.

Fesq, Lorraine↗

On-demand Command and Control of ASTERIA with Cloud-based Ground Station Services

ASTERIA (Arcsecond Space Telescope Enabling Research in Astrophysics) was a 6-unit CubeSat technology demonstration mission that deployed from the International Space Station on November 20th, 2017. After successfully completing its 90-day primary mission that demonstrated arcsecond-level line-of-sight pointing and focal plane thermal stability for exoplanet detection, it entered an extended mission performing onboard software demonstrations to mature technology both in space and on the ground. One of the technologies was a completely cloud-based ground system leveraging Amazon Web Services (AWS) Ground Station service. Announced in December 2018 and launched in May 2019, AWS Ground Station is a fully managed ground station service that aims to reduce the overhead associated with developing and maintaining ground system infrastructure throughout the mission lifecycle. AWS Ground Station makes available the suite of features required for any ground system in support of low-Earth orbit (LEO) and medium-Earth Orbit (MEO) satellite operations on-demand and without setting up or maintaining long-term contracts. Charges are incurred on a per-minute basis for antenna usage during scheduled tracks. Support is available for S-band uplink and downlink, along with X-band narrowband and wideband downlink. Missions that use the service may reserve tracks with any licensed AWS Ground Station antennas located across each service region and have direct access to any AWS services in support of mission operations. The cloud-based architecture built around the AWS Ground Station service greatly enhanced ASTERIA mission operations by enabling end-to-end pass automation, on-demand contact scheduling and contingency planning, along with more efficient data downlink through station availability and station-tostation handovers. It incorporated open-source software, particularly NASA's AMMOS Instrument Toolkit (AIT) and Open Mission Control Technologies (OpenMCT), along with the AWS application programming interfaces (API) to the Ground Station, Elastic Compute Cloud (EC2) and Simple Storage Service (S3) services. After showcasing operability in August 2019, the team continued using and improving this novel ground system architecture until the end of mission in December 2019. This paper describes the cloud-based ground system, how it was designed, tested, and evaluated with an inorbit spacecraft, the operational capabilities that it enabled, along with lessons learned and recommendations for future missions.

Fesq, Lorraine↗

A Nonlinear Dynamic Inversion Predictor-Based Model Reference Adaptive Controller for a Generic Transport Model

Presented here is a Predictor-Based Model Reference Adaptive Control (PMRAC) architecture for a generic transport aircraft. At its core, this architecture features a three-axis, non-linear, dynamic-inversion controller. Command inputs for this baseline controller are provided by pilot roll-rate, pitch-rate, and sideslip commands. This paper will first thoroughly present the baseline controller followed by a description of the PMRAC adaptive augmentation to this control system. Results are presented via a full-scale, nonlinear simulation of NASA s Generic Transport Model (GTM).

Campbell, Stefan F.↗

Structural Pain Compensating Flight Control

The problem of control command and maneuver induced structural loads is an important aspect of any control system design. Designers must design the aircraft structure and the control architecture to achieve desired piloted control responses while limiting the imparted structural loads. The classical approach is to build the structure with high margins, restrict control surface commands to known good combinations, and train pilots to follow procedural maneuvering limitations. With recent advances in structural sensing and the continued desire to improve safety and vehicle fuel efficiency, it is both possible and desirable to develop control architectures that enable lighter vehicle weights while maintaining and improving protection against structural damage.

advanced autonomy↗

Optimal Control Allocation with Load Sensor Feedback for Active Load Suppression, Experiment Development

The problem of control command and maneuver induced structural loads is an important aspect of any control system design. The aircraft structure and the control architecture must be designed to achieve desired piloted control responses while limiting the imparted structural loads. The classical approach is to utilize high structural margins, restrict control surface commands to a limited set of analyzed combinations, and train pilots to follow procedural maneuvering limitations. With recent advances in structural sensing and the continued desire to improve safety and vehicle fuel efficiency, it is both possible and desirable to develop control architectures that enable lighter vehicle weights while maintaining and improving protection against structural damage. An optimal control technique has been explored and shown to achieve desirable vehicle control performance while limiting sensed structural loads. The subject of this paper is the design of the optimal control architecture, and provides the reader with some techniques for tailoring the architecture, along with detailed simulation results.

controls↗

Optimal Control Allocation with Load Sensor Feedback for Active Load Suppression, Flight-Test Performance

The problem of control command and maneuver induced structural loads is an important aspect of any control system design. The aircraft structure and the control architecture must be designed to achieve desired piloted control responses while limiting the imparted structural loads. The classical approach is to utilize high structural margins, restrict control surface commands to a limited set of analyzed combinations, and train pilots to follow procedural maneuvering limitations. With recent advances in structural sensing and the continued desire to improve safety and vehicle fuel efficiency, it is both possible and desirable to develop control architectures that enable lighter vehicle weights while maintaining and improving protection against structural damage. An optimal control technique has been explored and shown to achieve desirable vehicle control performance while limiting sensed structural loads to specified values. This technique has been implemented and flown on the National Aeronautics and Space Administration Full-scale Advanced Systems Testbed aircraft. The flight tests illustrate that the approach achieves the desired performance and show promising potential benefits. The flights also uncovered some important issues that will need to be addressed for production application.

cFOSS↗

Revised Simulation Model of the Control System, Displays, and Propulsion System for a ASTOVL Lift Fan Aircraft

This report describes revisions to a simulation model that was developed for use in piloted evaluations of takeoff, transition, hover, and landing characteristics of an advanced short takeoff and vertical landing lift fan fighter aircraft. These revisions have been made to the flight/propulsion control system, head-up display, and propulsion system to reflect recent flight and simulation experience with short takeoff and vertical landing operations. They include nonlinear inverse control laws in all axes (eliminating earlier versions with state rate feedback), throttle scaling laws for flightpath and thrust command, control selector commands apportioned based on relative effectiveness of the individual controls, lateral guidance algorithms that provide more flexibility for terminal area operations, and a simpler representation of the propulsion system. The model includes modes tailored to the phases of the aircraft's operation, with several response types which are coupled to the aircraft's aerodynamic and propulsion system effectors through a control selector tailored to the propulsion system. Head-up display modes for approach and hover are integrated with the corresponding control modes. Propulsion system components modeled include a remote lift fan and a lift-cruise engine. Their static performance and dynamic responses are represented by the model. A separate report describes the subsonic, power-off aerodynamics and jet induced aerodynamics in hover and forward flight, including ground effects.

Franklin, James A.↗

Astrometric Telescope Facility For The Space Station

Paper discusses proposed Astrometric Telescope Facility, installed on Space Station to study motions of stars other than Sun and possibly detect planets around them. Measurements expected to verify, modify, or refute current theories about accretion of interplanetary clouds into stars and planets. Also measures motions and distances between stars and star clusters in nearby galaxies and in our own galaxy. System consists of six subsystems (optics, structure, thermal control, command and data, pointing and control, and power and harness) in addition to focal-plane instrument composed of Ronchi ruling and drive assembly, folding and field optics, multichannel astrometric photometer, and visible imager. Elements measure relative motions of stars with accuracy of 10 microarcseconds.

Nishioka, K.↗