Guidance, Navigation, and Control

Guidance, Navigation, and Control (GN&C) provides full life-cycle engineering development for spacecraft attitude and orbit determination and control systems. GN&C also develops high-fidelity launch vehicle guidance and control simulations as well as performance and robustness assessment tools for NASA. Controls design and analyses capabilities have been utilized for servo-mechanism applications for flight instruments. Specifically, capabilities include

• Attitude Control System (ACS) engineering, including spacecraft pointing budgets, instrument alignment and calibration, operations and contingency planning, risk identification and mitigation, and project reviews
• ACS conceptual developments for 3-axis stabilized, momentum bias, and spin-stabilized spacecraft
• Detailed design and analysis of GN&C control algorithms including linear and non-linear stability analyses, GPS⁄INS integration, and launch vehicle and missile GN&C
• Design and analysis of attitude determination, estimation, and Kalman filtering and algorithms including Stellar-Inertial attitude determination
• Multi-body dynamics analyses and simulations including separation mechanism kinematics, fuel-slosh, and boom / wire deployments
• LQR and MIMO Controls Design and Analysis
• Orbital mechanics and orbit determination
• Animated 3-D graphics of satellite and rockets
• GN&C hardware and software component engineering, interfaces, and specifications
• Flight hardware and software procurement, technical monitoring, and manufacturing and testing oversight
• Servo-mechanism control design, analysis and simulation for motors, gimbals, optical systems, etc.
• Wavefront sensing and control ⁄ fine and guidance ⁄LOS jitter
• Hardware-in-the-loop test planning and execution
• ACS integration and test; spacecraft-level phasing tests
• On-orbit sustaining engineering including flight alignment calibrations, trend analyses, and anomaly investigation and resolution.

Spacecraft autonomy  fault management

•

•

•

•

•

•

Orbital and navigation   analyses

•

•

•

•

Attitude Control Subsystem  engineering

•

•

•

•

•

•

•

•

•

•

ACS/dynamics design,  analysis and simulation

•

•

•

•

•

•

•

•

•

•

Attitude or orbit  determination

•

•

•

•

•

•

•

•

Propulsion design, analysis  and/or operations

•

•

•

•

•

•

Instrument Pointing Control   and Calibration

•

•

•

•

•

•

•

Hardware-in-the-Loop  Development Test

•

•

•

•

Component selection and  technical monitoring

•

•

•

•

Integration and test support

•

•

•

•

•

•

Launch and Early Orbit  and/or Mission Ops

•

•

•

•

Launch vehicle analysis  and simulation

•

•

GN&C expertise covers all aspects of spacecraft, missiles, and launch vehicle GN&C engineering and has been applied across a range of projects including our recent significant efforts summarized in the table. For the NASA New Millennium Program EO-1 spacecraft, GN&C provided the complete design, development, analysis, implementation, and testing of the attitude control subsystem. We have provided algorithms for the Image Navigation and Registration of the GOES weather satellites and ACS lead engineering for the TDRS communication satellites. For the TOPEX / Poseidon spacecraft, GN&C provided subsystem on-orbit performance trending, maintenance, and anomaly resolution support for over nine years. GN&C personnel are actively working on the fine guidance systems required for the James Webb Space Telescope. As part of the KSC Expendable Launch Vehicle team, GN&C has developed high-fidelity guidance and control simulations of the Pegasus, Delta-II, and Delta-III rockets. This Independent Verification and Validation effort has been utilized by NASA for launch anomaly investigations.

GN&C Design, Analyses, and Simulation Tools

Contact

space@atk.com