Engineering topics
Reinholtz, Kirk
Publications and source records attributed to Reinholtz, Kirk.
Project-domain Science Traceability and Alignment Framework (P-STAF): Analysis of a Payload Architecture
Large science-focused space missions often have multiple instruments working together to address broad science goals. Systems engineers on these types of projects must work with the project scientists to evaluate trades and make decisions that result in a system that efficiently serves the mission science goals. This collaboration is more effective if the systems engineers understand both the traceability from the L1 customer requirements to the selected instruments and the contributions of each instrument in the context of the whole payload suite. These relationships might be understood implicitly by the science team on a project, but there is value in formally codifying them so this understanding can be accessed and formally analyzed by a broader systems engineering effort. We first described a framework for this communication, called the Project-domain Science Traceability and Alignment Framework (P-STAF), in the IEEE 2017 paper “A Framework for Extending the Science Traceability Matrix: Application to the Planned Europa Mission.” This paper shows how that basic framework can be leveraged to not only formally capture these relationships between the instruments and the customer needs, but also how that information can be codified in an analyzable graph that can be queried to provide a better understanding of mission risks and scope. This work was drawn from the application of P-STAF to the Europa Clipper mission, but generic example networks are used to illustrate the power of this technique.
Timeline as Unifying Concept for Spacecraft Operations
The notion of Timeline has been used informally in spacecraft operations software for some time, but it has not heretofore been formalized and unified either syntactically or semantically. We have formalized and unified the Timeline so that the commonality can be exploited to reduce the cost of developing and using spacecraft operations software. The Timeline can then be used as the common data structure for storage and communications between spacecraft planning and operations software elements.
Managing Complexity in Next Generation Robotic Spacecraft: From a Software Perspective
This presentation highlights the challenges in the design of software to support robotic spacecraft. Robotic spacecraft offer a higher degree of autonomy, however currently more capabilities are required, primarily in the software, while providing the same or higher degree of reliability. The complexity of designing such an autonomous system is great, particularly while attempting to address the needs for increased capabilities and high reliability without increased needs for time or money. The efforts to develop programming models for the new hardware and the integration of software architecture are highlighted.
Project Golden Gate: towards real-time Java in space missions
This paper describes the problem domain and our experimentation with the first commercial implementation of the Real Time Specification for Java. The two main issues explored in this report are: (1) the effect of RTSJ's non-heap memory on the programming model, and (2) performance benchmarking of RTSJ/Linux relative to C++/VxWorks.
Separating essentials from incidentals: an execution architecture for real-time control systems
This paper describes an execution architecture that makes such systems far more analyzable and verifiable by aggressive separation of concerns. The architecture separates two key software concerns: transformations of global state, as defined in pure functions; and sequencing/timing of transformations, as performed by an engine that enforces four prime invariants. The important advantage of this architecture, besides facilitating verification, is that it encourages formal specification of systems in a vocabulary that brings systems engineering closer to software engineering.
Testing Autonomous Systems for Deep Space Exploration
NASA is moving into an era of increasing spacecraft autonomy. However, before autonomy can be routinely utilized, we must provide techniques for providing assurance that the system will perform correctly in flight.
High-Performance Software Emulation of 1750A Processor
We describe a software emulator of the MIL-STD-1750A architecture that executes 1750A code at a rate of about 4 MIPS on a Sun 200MHz Ultra2 work-station, and effectively several times faster than that when application-specific optimizations are used.
The TSTAR Autonomy Test Tool
The new breed of autonomous goal-driven spacecraft contain much more onboard capability than their syquence-driven predecessors, demanding corresponding advances in software verification techniques. Although autonomous systems are deterministic, they are hightly sensitive to the environment, such that the response of a system in certain contexts must be explored in detail in order to prove confidence in both the design and implementaiton.
A Multithreaded Scheduler for a High-Speed Spacecraft Simulator
The Cassini Spacecraft will soon journey to Saturn to perform a close-up study of the Saturnian system; its rings, moons, magneto-sphere, andf the planet itelf. Sequences of commands will be sent to the spacecraft by ground personnel to control every aspect of the mission. To validate and verify these command sequences, a bit-level, high-speed simulator (HSS) has been developed.
The use of Tcl and Tk to improve design and code reutilization
Tcl and Tk facilitate design and code reuse in the ZIPSIM series of high-performance, high-fidelity spacecraft simulators. Tcl and Tk provide a framework for the construction of the Graphical User Interfaces for the simulators. The interfaces are architected such that a large proportion of the design and code is used for several applications, which has reduced design time and life-cycle costs.
Teh ZIPSIM Series of High Performance , High Fidelity Spacecraft Simulators
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Multimission High Speed Spacecraft Simulation For The Galileo and Cassini Mission
A Simulation system has been developed which is capable of bit level simulation of spacecraft data systems. Object oriented techniques and an embedded interpreted language hae been employed to produce a highly configurable tool for control and viewing of spacecraft states.
Multimission High Speed Spacecraft Simulation
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