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At least 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
NASA NTRS2009

Oxygen Generation System Laptop Bus Controller Flight Software

The Oxygen Generation System Laptop Bus Controller Flight Software was developed to allow the International Space Station (ISS) program to activate specific components of the Oxygen Generation System (OGS) to perform a checkout of key hardware operation in a microgravity environment, as well as to perform preventative maintenance operations of system valves during a long period of what would otherwise be hardware dormancy. The software provides direct connectivity to the OGS Firmware Controller with pre-programmed tasks operated by on-orbit astronauts to exercise OGS valves and motors. The software is used to manipulate the pump, separator, and valves to alleviate the concerns of hardware problems due to long-term inactivity and to allow for operational verification of microgravity-sensitive components early enough so that, if problems are found, they can be addressed before the hardware is required for operation on-orbit. The decision was made to use existing on-orbit IBM ThinkPad A31p laptops and MIL-STD-1553B interface cards as the hardware configuration. The software at the time of this reporting was developed and tested for use under the Windows 2000 Professional operating system to ensure compatibility with the existing on-orbit computer systems.

Rowe, Chad↗
NASA NTRS1984

Executable assertions and flight software

It is pointed out that executable assertions can be used for dynamic testing of software. An executable assertion is a logical statement about the variables or a block of code. If there is no error during execution then the assertion statement results in a true value. Assertions are useful for testing purposes throughout the lifecycle of software. They can be used for validation during the design phase, and for exception handling and error detection during the operation phase. The present investigation has the objective to study the use of executable assertions for testing flight software. Attention is given to details regarding executable assertions, the digital flight control system, testing flight software, and preliminary experimental results.

Mahmood, A.↗
NASA NTRS1991

Lessons learned from Space Shuttle flight software and Mission Control software

The techniques utilized by NASA to manage risk in the development and operations of flight software and Mission Control Center software for the Space Shuttle are reviewed. Particular attention is given to independent software in the backup flight system, structured requirements and design techniques, multiple levels of testing in development and production, independent testing following production, and independence of development and production, and the Mission Control Center model for Real Time Data System project.

Muratore, John F.↗
NASA NTRS2013

On a Formal Tool for Reasoning About Flight Software Cost Analysis

A report focuses on the development of flight software (FSW) cost estimates for 16 Discovery-class missions at JPL. The techniques and procedures developed enabled streamlining of the FSW analysis process, and provided instantaneous confirmation that the data and processes used for these estimates were consistent across all missions. The research provides direction as to how to build a prototype rule-based system for FSW cost estimation that would provide (1) FSW cost estimates, (2) explanation of how the estimates were arrived at, (3) mapping of costs, (4) mathematical trend charts with explanations of why the trends are what they are, (5) tables with ancillary FSW data of interest to analysts, (6) a facility for expert modification/enhancement of the rules, and (7) a basis for conceptually convenient expansion into more complex, useful, and general rule-based systems.

Spagnuolo, John N., Jr.↗
NASA NTRS2019

SSIM: NASA Mars rover robotics flight software simulation

The focus of SSim on MSL was the robotic flight software, including rover mobility and navigation, robotic arm manipulation, and sample acquisition, processing, and delivery. It can execute behaviors in simulation a thousand times faster than they execute in real time on the flight compute element. SSim is used by rover drivers to develop and validate command sequences throughout the planning cycle. SSim has been used to plan all of the Curiosity robotic operations since landing and is expected to continue to be used for the remaining life of the rover.

Leger, Chris↗
NASA NTRS2014

Spot: A Programming Language for Verified Flight Software

The C programming language is widely used for programming space flight software and other safety-critical real time systems. C, however, is far from ideal for this purpose: as is well known, it is both low-level and unsafe. This paper describes Spot, a language derived from C for programming space flight systems. Spot aims to maintain compatibility with existing C code while improving the language and supporting verification with the SPIN model checker. The major features of Spot include actor-based concurrency, distributed state with message passing and transactional updates, and annotations for testing and verification. Spot also supports domain-specific annotations for managing spacecraft state, e.g., communicating telemetry information to the ground. We describe the motivation and design rationale for Spot, give an overview of the design, provide examples of Spot's capabilities, and discuss the current status of the implementation.

validation↗
NASA NTRS2018

Increasing Flight Software Reuse with OpenSatKit

In January 2015 the NASA Goddard Space Flight Center (GSFC) released the Core Flight System (cFS) as open source under the NASA Open Source Agreement (NOSA) license. The cFS is based on flight software (FSW) developed for 12 spacecraft spanning nearly two decades of effort and it can provide about a third of the FSW functionality for a low-earth orbiting scientific spacecraft. The cFS is a FSW framework that is portable, configurable, and extendable using a product line deployment model. However, the components are maintained separately so the user must configure, integrate, and deploy them as a cohesive functional system. This can be very challenging especially for organizations such as universities building cubesats that have minimal experience developing FSW. Supporting universities was one of the primary motivators for releasing the cFS under NOSA. This paper describes the OpenSatKit that was developed to address the cFS deployment challenges and to serve as a cFS training platform for new users. It provides a fully functional out-of-the box software system that includes NASA's cFS, Ball Aerospace's command and control system COSMOS, and a NASA dynamic simulator called 42. The kit is freely available since all of the components have been released as open source. The kit runs on a Linux platform, includes 8 cFS applications, several kit-specific applications, and built in demos illustrating how to use key application features. It also includes the software necessary to port the cFS to a Raspberry Pi and instructions for configuring COSMOS to communicate with the target. All of the demos and test scripts can be rerun unchanged with the cFS running on the Raspberry Pi. The cFS uses a 3-tiered layered architecture including a platform abstraction layer, a Core Flight Executive (cFE) middle layer, and an application layer. Similar to smart phones, the cFS application layer is the key architectural feature for users to extend the FSW functionality to meet their mission-specific requirements. The platform abstraction layer and the cFE layers go a step further than smart phones by providing a platform-agnostic Application Programmer Interface (API) that allows applications to run unchanged on different platforms. OpenSatKit can serve two significant architectural roles that will further help the adoption of the cFS and help create a community of users that can share assets. First, the kit is being enhanced to automate the integration of applications with the goal of creating a virtual cFS "App Store".. Second, a platform certification test suite can be developed that would allow users to verify the port of the cFS to a new platform. This paper will describe the current state of these efforts and future plans.

Computer Programming and Software↗
NASA NTRS2018

Increasing Flight Software Reuse with OpenSatKit

In January 2015 the NASA Goddard Space Flight Center (GSFC) released the Core Flight System (cFS) as open source under the NASA Open Source Agreement (NOSA) license. The cFS is based on flight software (FSW) developed for 12 spacecraft spanning nearly two decades of effort and it can provide about a third of the FSW functionality for a low-earth orbiting scientific spacecraft. The cFS is a FSW framework that is portable, configurable, and extendable using a product line deployment model. However, the components are maintained separately so the user must configure, integrate, and deploy them as a cohesive functional system. This can be very challenging especially for organizations such as universities building cubesats that have minimal experience developing FSW. Supporting universities was one of the primary motivators for releasing the cFS under NOSA. This paper describes the OpenSatKit that was developed to address the cFS deployment challenges and to serve as a cFS training platform for new users. It provides a fully functional out-of-the box software system that includes NASA's cFS, Ball Aerospaceâ€"TM"s command and control system COSMOS, and a NASA dynamic simulator called 42. The kit is freely available since all of the components have been released as open source. The kit runs on a Linux platform, includes 8 cFS applications, several kit-specific applications, and built in demos illustrating how to use key application features. It also includes the software necessary to port the cFS to a Raspberry Pi and instructions for configuring COSMOS to communicate with the target. All of the demos and test scripts can be rerun unchanged with the cFS running on the Raspberry Pi. The cFS uses a 3-tiered layered architecture including a platform abstraction layer, a Core Flight Executive (cFE) middle layer, and an application layer. Similar to smart phones, the cFS application layer is the key architectural feature for userâ€"TM"s to extend the FSW functionality to meet their mission-specific requirements. The platform abstraction layer and the cFE layers go a step further than smart phones by providing a platform-agnostic Application Programmer Interface (API) that allows applications to run unchanged on different platforms. OpenSatKit can serve two significant architectural roles that will further help the adoption of the cFS and help create a community of users that can share assets. First, the kit is being enhanced to automate the integration of applications with the goal of creating a virtual cFS 'App Store'. Second, a platform certification test suite can be developed that would allow users to verify the port of the cFS to a new platform. This paper will describe the current state of these efforts and future plans.

McComas, David↗
NASA NTRS2011

Wake Cycle Robustness of the Mars Science Laboratory Flight Software

The Mars Science Laboratory (MSL) is a spacecraft being developed by the Jet Propulsion Laboratory (JPL) for the purpose of in-situ exploration on the surface of Mars. The objective of MSL is to explore and quantitatively assess a local region on the Martian surface as a habitat for microbial life, past or present. This objective will be accomplished through the assessment of the biological potential of at least one target environment, the characterization of the geology and geochemistry of the landing region, an investigation of the planetary process relevant to past habitability, and a characterization of surface radiation. For this purpose, MSL incorporates a total of ten scientific instruments for which functions are to include, among others, atmospheric and descent imaging, chemical composition analysis, and radiation measurement. The Flight Software (FSW) system is responsible for all mission phases, including launch, cruise, entry-descent-landing, and surface operation of the rover. Because of the essential nature of flight software to project success, each of the software modules is undergoing extensive testing to identify and correct errors.

Whitehill, Robert↗
NASA NTRSDate not supplied

Emulation of Core Flight System Applications for Flight Software Development and Validation

The Mars Sample Return (MSR) campaign is an unprecedented attempt in the return of Martian samples back to Earth. The ascent from the surface will be performed by the Mars Ascent Vehicle (MAV), a critical element in the mission that National Aeronautics and Space Administration (NASA) Marshall Space Flight Center (MSFC) is developing. To this end, innovations in flight software development, verification, and validation are occurring. The MAV flight computer will run Core Flight System (cFS), an open-source software environment developed by NASA Goddard Space Flight Center (GSFC). NASA Marshall’s MAV Mission and Fault Management (M&FM) Team has implemented an emulation of two applications of this architecture: Limit Checker and Stored Command. Using an emulation of the functionalities of these applications allows for rapid prototyping of table-based algorithms. Further, M&FM is leveraging an in-house, low-fidelity but high-throughput State Analysis Model (SAM), an integrated MATLAB Stateflow Plant and Software model. This model is run in parallel with the cFS emulation for full flyout testing of the M&FM algorithms, verification of intent of these algorithms, and for future auto-generation of application-ingestible M&FM tables. The tables can then be delivered to the MAV Flight Software (FSW) team in a seamless process, reducing the cost of traditional FSW development and the risk of starting M&FM FSW development at later points in the NASA program life cycle.

Cody Wheeler↗
NASA NTRSDate not supplied

Emulation of Core Flight System Applications for Flight Software Development and Validation

The Mars Sample Return (MSR) campaign is an unprecedented attempt in the return of Martian samples back to Earth. The ascent from the surface will be performed by the Mars Ascent Vehicle (MAV), a critical element in the mission that National Aeronautics and Space Administration (NASA) Marshall Space Flight Center (MSFC) is developing. To this end, innovations in flight software development, verification, and validation are occurring. The MAV flight computer will run Core Flight System (cFS), an open-source software environment developed by NASA Goddard Space Flight Center (GSFC). NASA Marshall’s MAV Mission and Fault Management (M&FM) Team has implemented an emulation of two applications of this architecture: Limit Checker and Stored Command. Using an emulation of the functionalities of these applications allows for rapid prototyping of table-based algorithms. Further, M&FM is leveraging an in-house, low-fidelity but high-throughput State Analysis Model (SAM), an integrated MATLAB Stateflow Plant and Software model. This model is run in parallel with the cFS emulation for full flyout testing of the M&FM algorithms, verification of intent of these algorithms, and for future auto-generation of application-ingestible M&FM tables. The tables can then be delivered to the MAV Flight Software (FSW) team in a seamless process, reducing the cost of traditional FSW development and the risk of starting M&FM FSW development at later points in the NASA program life cycle.

Cody Wheeler↗
NASA NTRSDate not supplied

Psyche Hardware Abstraction Simulation Environment (PHASE): Development of High-Fidelity Downlink Model for Flight Software Performance Testing

NASA’s Katherine Johnson Independent Verification and Validation (IV&V) Independent Test Capability (ITC) Team develops high fidelity software-only simulations (or “digital-twins”) of NASA’s most critical missions that are then used for software verification and validation (V&V). One such digital-twin simulator nearing maturity is the Psyche Hardware Abstraction Simulation Environment (PHASE). PHASE utilizes an instruction set simulator along with ITC-developed avionics models. PHASE includes a newly-developed model of the telecom hardware with a high-fidelity downlink interface, capable of supporting reconfigurable downlink data rates and transmission modes. The different downlink transmission modes allow more processing to be ceded from software onto the telecom hardware. Thus, we are able to monitor the performance of the downlink software module in the time-partitioned OS and perform more realistic dynamic testing based on software’s resource utilization. This presentation will cover PHASE, avionics modeling, the downlink model, and its usage for flight software performance testing.

modeling↗
NASA NTRS1979

Simulation use in the development and validation of HiMAT flight software

The use of real time simulation in the development and validation of flight software for the highly maneuverable aircraft technology (HiMAT) remotely piloted research vehicle is described. Four simulations are interfaced with varying amounts of actual flight hardware to produce dynamic system operation.

Myers, A.↗
NASA NTRS2012

Improving Flight Software Module Validation Efforts : a Modular, Extendable Testbed Software Framework

Ever since Explorer-1, the United States' first Earth satellite, was developed and launched in 1958, JPL has developed many more spacecraft, including landers and orbiters. While these spacecraft vary greatly in their missions, capabilities,and destination, they all have something in common. All of the components of these spacecraft had to be comprehensively tested. While thorough testing is important to mitigate risk, it is also a very expensive and time consuming process. Thankfully,since virtually all of the software testing procedures for SMAP are computer controlled, these procedures can be automated. Most people testing SMAP flight software (FSW) would only need to write tests that exercise specific requirements and then check the filtered results to verify everything occurred as planned. This gives developers the ability to automatically launch tests on the testbed, distill the resulting logs into only the important information, generate validation documentation, and then deliver the documentation to management. With many of the steps in FSW testing automated, developers can use their limited time more effectively and can validate SMAP FSW modules quicker and test them more rigorously. As a result of the various benefits of automating much of the testing process, management is considering this automated tools use in future FSW validation efforts.

flight software testing↗
NASA NTRSDate not supplied

Flight Software for the LOFTID Re-Entry Vehicle

NASA’s Low-Earth Orbit Flight Test of an Inflatable Decelerator, or LOFTID, demonstrated re-entry from low-Earth orbit of a 6-meter aeroshell designed to be used as a heat shield that is larger than the rocket shroud, enabling the return of much greater mass. The LOFTID Flight Software was developed in-house and consists of three components: the Power Distribution software, the Data Recorder software, and the Camera Controller software, along with the Ground Software used for testing, operations, data integrity, and data processing. This presentation will discuss issues found in developing the Power Distribution software in cFS on a non-Linux POSIX platform, designing an efficient architecture for recording of high bandwidth data, controlling over a dozen cameras in-flight, and creating the ground support tools to verify data integrity and support the post-processing of flight data.

Paul Brewster↗