Systems Engineering for Space Vehicles

Bryan Palaszewskiwith the

Digital Learning NetworkNASA Glenn Research Center

Cleveland, OH

Introduction

• What is systems engineering?

• How does systems engineering apply to space missions?

• How does systems engineering help us explore space?

What is Systems Engineering? (1/4)

• Systems engineering is a process by which all of the important aspects or subsystems of space vehicles and their interactions are introduced, studied, and used.

• The interactions of the systems are studied, making sure they all work together harmoniously.

What is Systems Engineering? (2/4)

• “Systems engineering is an interdisciplinary approach encompassing the entire technical effort to evolve and verify an integrated and life-cycle balanced set of system people, product, and process solutions that satisfy customer needs."

Shishko, R., NASA Systems Engineering Handbook, NASA SP-6105, 1995.

What is Systems Engineering? (3/4)

• “Systems engineering is a robust approach to the design, creation, and operation of systems.

• In simple terms, the approach consists of identification and quantification of system goals, creation of alternative system design concepts, performance of design trades, selection and implementation of the best design, …

What is Systems Engineering? (4/4)

• … verification that the design is properly built and integrated, and post-implementation assessment of how well the system meets (or met) the goals.”

Shishko, R., NASA Systems Engineering Handbook, NASA SP-6105, 1995.

How Does Systems Engineering Apply To Space Missions? (1/2)

• Space vehicles are very complex with many subsystems.

• Each subsystem has many components, and the interactions of those components can lead to unexpected or unpredictable results.

How Does Systems Engineering Apply To Space Missions? (2/2)

• Safe and reliable operation of a spacecraft requires a rich knowledge of these interactions.

How Does Systems Engineering Help Us Explore Space?

• The process of systems engineering identifies potential flaws in the space vehicle before launch.

• Systems engineering allows for safer missions, and a better chance for mission success.

Typical Subsystems (1/3)

• Propulsion• Power• Power processing• Structures• Heat transfer• Fluid systems• Telecommunications

Propulsion

Power: Solar Array

Power Processing

• Changes power at one set current and voltage into the proper currents and voltages for other parts of the spacecraft. Test hardware for

power processor

Structures

Structures

Structures

Heat Transfer: Radiator for Heat Rejection

Typical Subsystems (2/3)

• Attitude control

• Navigation

• Mechanisms

• Payload(s)

• Docking (under Mechanisms, etc.)

• Life support

Guidance, Navigation, and Control Subsystem

Environmental Control and Life Support Subsystem

Typical Subsystems (3/3)

• Pyrotechnics

• Cabling

• Configuration control

• Other aspects:– Environments (radiation, contamination)– Vibration testing, overall system testing– Fracture control (propellant tankage)– Simulation, Information Technology, and

many others

Layout of Nuclear Electric Propulsion (NEP) Vehicle