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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
NASA NTRS1993

Mission Operations and Command Assurance: Automating an Operations TQM Task

A long-term program is in progress at JPL to reduce cost and risk of mission operations through defect prevention and error management. A major element of this program, Mission Operations and Command Assurance (MO&QA), provides a system level function on flight projects to instill quality in mission operations. MO&CA embodies the Total Quality Management (TQM) principle of Continuous Process Inprovement (CPI) and uses CPI in applying automation to mission operations to reduce risk and costs. MO&CA has led efforts to apply and has implemented automation in areas that impact the daily flight project environment including Incident Surprise Anomoly tracking and reporting; command data verification, tracking, and reporting; and command support data usage. MO&CA's future work in automation will take into account that future missions systems must be designed to avoid increasing error through the introduction of automation, while adapting to the demands of smaller flight teams.

automation↗
NASA NTRS2020

Developing and Implementing a Process to Verify and Validate the NASA InSight Mission’s Instrument Command Products

The NASA InSight Mars lander is a roboticspacecraft which is investigating the interior structure of Marsthrough a series of seismological measurements andexperiments. Much of the commanding of activities performedby the instruments was done using ‘blocks’ – reusable functionswritten in Virtual Machine Language stored onboard thespacecraft– and sequences (series of commands) that werecreated by teams to operate their instruments. It was vital thatthese blocks and sequences (collectively called commandproducts) be thoroughly examined prior to onboard executionusing a comprehensive test program to reduce risk to thespacecraft and instruments and ensure smooth operations onthe surface of Mars. The Verification and Validation (V&V)process that was designed and implemented during the monthsleading up to InSight’s launch and landing successfullyuncovered a number of issues that could have causedoperational delays or impacted hardware. The process alsohelped adapt ground tools to better model onboard activities,create operational principles to avoid unintended consequencesduring flight, and generate a reference database for commandproduct use during operations. This allowed InSight to meet itssurface operations goals in the desired timeframe. This paperdescribes the development, implementation and results ofInSight’s command product V&V process, its contribution tomission success, and challenges faced.

Cloutier, Kyle↗
NASA NTRS2020

MEXEC: An Onboard Integrated Planning and Execution Approach for Spacecraft Commanding

The traditional form of spacecraft commanding is with sequences that specify when commands should execute based on a schedule generated on the ground. Some sequences have control logic and event driven responses to increase flexibility, but it is limited. An approach to increase autonomy is to use goal-based planning and commanding. Using this paradigm, intention and behavior is modeled on board the spacecraft. In this paper we describe MEXEC (Multi-mission EXECutive), a multi-mission, task-based, onboard planning and execution software designed specifically to be used as flight software. As a path to infusion for future flight projects, we describe two experiments performed on the ASTERIA CubeSat and testbed that demonstrate that MEXEC can be integrated and used for spacecraft operations and increase robustness and science return compared to the standard sequences that were being used.

Campuzano, Brian↗
NASA NTRSDate not supplied

Reference Command Optimization for the Transition Flight Mode of a Lift plus Cruise Vehicle

Advanced air mobility mainly utilizes vehicles that are capable of vertical takeoff and landing (VTOL) for the simplicity of operation and large-scale deployment. However, VTOL vehicles need specialized trajectory and command design for the transition phase, where the vehicles transition between rotor-borne flight and wing-borne flight. Since VTOL vehicles are commonly designed as over-actuated systems for redundancy, one challenge that arises is actuator ambiguity, where it is unclear how to uniquely command actuators for the VTOL vehicle to track a given trajectory. We propose a method to design optimal reference commands for the transition mode. By formulating an 𝑙 1 -norm cost function on the rotor thrusts of the vehicle, we can achieve economical operation of the rotors such that they only operate when necessary and efficiently utilize the aerodynamics to save energy from reduced rotor actuation. We validate our approach in simulations and show its benefit compared to the commonly used differential flatness-based method.

John L Bullock↗
NASA NTRSDate not supplied

Command and Control Concepts for an Lift Plus Cruise Electric Vertical Takeoff and Landing Vehicle

Electric Vertical Takeoff and Landing (eVTOL) vehicles have the potential to enable cost effective Urban Air Mobility (UAM) applications. Many of these vehicle concepts will takeoff vertically like a helicopter, transition to fly like an airplane, and then transition back to land vertically like a helicopter. However, these concepts may also pose several challenging handling and control problems, which must be addressed prior to safe and reliable urban operations. This study investigates some of these challenges by evaluating different command and control concepts for a conceptual Lift Plus Cruise vehicle designed by NASA’s Revolutionary Vertical Lift Technology (RVLT) project. Four different command concepts with increasing levels of automation are developed. The command and control architecture for these concepts is presented along with findings from the evaluation of these concepts in a series of three piloted studies in the Vertical Motion Simulator at NASA Ames Research Center, where pilots flew operationally relevant flight test maneuvers specifically designed to expose potential deficiencies. The higher-level control systems and the associated pilot interfaces were shown to improve performance and handling in many cases, especially for higher precision and lower to moderate aggression maneuvers. The benefits were limited for higher aggression tasks in environmentally stressing conditions, due to the slower response of the automation and inherent limitations of the vehicle design, which highlights the potential need for tradeoffs between concept of operations and vehicle capabilities

Thomas Lombaerts↗
NASA NTRSDate not supplied

X-57 Traction Power and Command Systems Development

This paper describes the final, as-built design of the X‑57 Maxwell aircraft power and command system architecture that implements the electrified propulsion capability. The development of the traction power, command, and avionics power subsystems proceeded as planned at the initial project critical design review, but improvements to the design were identified following the development of detailed operations concepts and integrated subsystem and system testing. The redundant architecture with A‑side and B‑side buses provided a robust framework for a developmental system that would turn out to have a lower technology readiness than had been assumed upon project formulation. As the project team identified reliability or performance gaps in the electrified propulsion powertrain components and their interactions with the other vehicle systems, the traction power, command, and avionics architectures were modified to accommodate the modified systems. Following the publication of the planned design approach at the critical design review milestone [1], the project team developed the flight hardware and software, integrated the systems, and adjusted the design and qualification activities to address gaps in the components, system architecture, and requirements as the gaps were realized. In addition to inherent challenges in development of these subsystems, the integration of this new technology with adjacent critical systems in an aircraft configuration posed additional challenges that drove design considerations across the subsystem development and the other vehicle systems. Integration complications included electromagnetic compatibility, thermal performance, and tolerance of single-point failures internal and external to the powerplant. Development of a qualification program was required for the new motors, inverters, and batteries, and hardware performance during component qualification fed back into the development process and led lessons learned and redesign of key elements.

distributed propulsion↗
NASA NTRS1995

A High Efficiency System for Science Instrument Commanding for the Mars Global Surveyor Mission

The Mars Global Surveyor (MGS) mission will return to Mars to re- cover most of the science lost when the ill fated Mars Observer space- craft suffered a catastrophic anomaly in its propulsion system and did not go into orbit. Described in detail are the methods employed by the MGS Sequence Team to accelerate science command processing by using standard command generation process and standard UNIX control scripts.

mars global surveyor mission science instrument co↗
NASA NTRS1965

The command system

Ground commands and internal logic functions for Relay I satellite command system

COMMAND SYSTEM↗
NASA NTRS1966

GEOS command assignment

Satellite operational reliability by assigning command functions to relay matrix positions of command subsystem

SATELLITE COMMUNICATION↗
NASA NTRS2001

Telemetry, tracking, and command consolidation in the Deep Space Network

Currently, in NASA's Deep Space Network (DSN), telemetry, tracking, and command (TT&C) functions are distributed between multiple subsystem computers. Control design of these subsystems did not consider the interaction necessary between the functions, which create opportunities for loss of data. Also, the current controller design can force the use of equipment that is not needed for the task at hand, to the detriment of others. As part of the Network Simplification Project (NSP), the TTC implementation has been re-examined, New telemetry and commanding equipment is being built, and the control of the TT&C functions is being consolidated into two controllers, Uplink and Downlink. The new equipment uses commercial components, as opposed to the custom built equipment it is replacing, which improves reliability and simplifies maintenance.

tracking↗
NASA NTRS2016

Project Hermes 'Use of Smartphones for Receiving Telemetry and Commanding a Satellite'

TCPIP protocols can be applied for satellite command, control, and data transfer. Project Hermes was an experiment set-up to test the use of the TCPIP protocol for communicating with a space bound payload. The idea was successfully demonstrated on high altitude balloon flights and on a sub-orbital sounding rocket launched from NASAs Wallops Flight Facility. TCPIP protocols can be applied for satellite command, control, and data transfer. Project Hermes was an experiment set-up to test the use of the TCPIP protocol for communicating with a space bound payload. The idea was successfully demonstrated on high altitude balloon flights and on a sub-orbital sounding rocket launched from NASAs Wallops Flight Facility.

Telemetry↗
NASA NTRS1994

Fault Protection Design for the Command and Data Subsystem on the Cassini Spacecraft

The Command and Data Subsystem (CDS) on Cassini is responsible for uplink command processing, spacecraft intercommunications and control, and downlink telemetry formatting. The 10.7 year mission life, 160 minute round-trip light time, and extended periods of operation without continuous ground communications drive the CDS design in directions of redundancy, autonomy, and fault protection to accomodate the mission objectives.

Cassini↗
NASA NTRSDate not supplied

Software-Only Key Management and Cryptography (KMC) for Spacecraft Command Encryption

The Jet Propulsion Laboratory (JPL) Advanced Multi-Mission Operations System (AMMOS) in partnership with NASA’s Katherine Johnson Independent Verification and Validation (NASA IV&V) Jon McBride Software Testing and Research (JSTAR) laboratory have jointly developed a command encryption capability that provides a software-only encryption solution utilizing the CCSDS Space Data Link Security Protocol. This solution, named Key Management and Cryptography (KMC), incorporates JPL’s encryption service with the JSTAR open-source CryptoLib library, providing a solution for spacecraft command encryption, which is required per NASA standard NASA-STD-1006-A. This paper will focus on its design, usage, and operation for two SmallSat missions, along with its future expanded functionality of end-to-end spacecraft encryption.

command encryption↗
NASA NTRSDate not supplied

Lunar Command and Control Interoperability (LuCCI) Project Overview

The Lunar Command and Control Interoperability (LuCCI) project was formed to address a gap in how Lunar Surface Systems (LSS) would interoperate across multiple programs, commercial partners, and international partners. The project objective is to define, prototype, integrate, and evaluate an interoperable lunar command, control, data, and software reference architecture to enable autonomy and informatics capability through common standards across LSS.

Communications↗
NASA NTRS1972

Development and testing of the flight command subsystem for the Mariner Mars 1971 spacecraft

The flight command subsystem for the Mariner Mars 1971 spacecraft is of the same basic design and construction as that for Mariner Mars 1969 except for its expanded capability. Its primary purpose is to provide remote control for the spacecraft. This report briefly describes the design changes, fabrication, and significant problems associated with the development of the Mariner Mars 1971 flight command subsystem.

Chitty, W. H.↗