Guidance, navigation and control
Download as PPTX, PDF6 likes3,751 views
Guidance, navigation and control (GNC) deals with controlling the movement of space vehicles. GNC includes guidance to establish the desired path, navigation to determine the current and future position, and control actions to match the current position to the desired path. The key elements of GNC are guidance, navigation, control systems, and attitude control. GNC is essential for space missions to navigate from point to point, control the vehicle's orientation, and guide trajectories between planets and spacecraft pointing.
Guidance, navigation and control
- 1. Guidance, Navigation and control By Periyanayaga kristy. A M.Tech-Nanotechnology SRM University
- 2. Guidance, navigation and control • “...Guidance, navigation and control (abbreviated GNC) is a branch of engineering dealing with the design of systems to control the movement of space vehicles...” • GUIDANCE: establishment of the desired path to follow (current, i.e. in real-time and future). • NAVIGATION: establishment of the current and future state. • CONTROL: actions to match the current state (navigation) with the foreseen path (guidance) Definition
- 3. Guidance, navigation and control
- 4. Problem description: Position Want to “move” a space vehicle from point “A” to point “B” Guidance, navigation and control
- 5. Problem description: Attitude Want to “slew” the axis of a space vehicle from axis “A” to axis “B” Guidance, navigation and control
- 6. Simplified GNC block diagram Guidance, navigation and control
- 7. GNC elements Guidance, navigation and control
- 8. Definition Navigation • NAVIGATION is the process to find the present and future position and orbit of a spacecraft using a series of measurements. • Step 1: MEASURING Obtaining state vectors (x, y, z, Vx, Vy, Vz,...) at timely intervals. • Step 2: DETERMINING Reconstructing the orbit based on a set of state vectors. • Step 3: PREDICTING Forecasting the imminent future state vector Guidance, navigation and control
- 9. Spacecraft Control • Minimize the spacecraft propellant mass or overall mass, hence reducing mission cost. • Increase the accuracy of the control when tracking or regulating the plant. • Increase the agility of the spacecraft maneuvers. • Facilitate the overall design process of the GNC subsystem, hence reducing mission cost. Guidance, navigation and control
- 10. Attitude control Guidance, navigation and control
- 11. Spacecraft Pointing Control Guidance, navigation and control
- 12. Broad Control System Categories Guidance, navigation and control
- 13. Interplanetary Vehicles and GNC: • Fly-by between planets • Mid-course correction maneuvers • Optimal pointing of antennae to ground stations Station. • keeping in Lagrangian points Guidance, navigation and control
- 14. Missions Examples • High pointing accuracy on attitude stabilization agility on attitude slew. Guidance, navigation and control
- 15. GNC for launchers • Trajectory optimization of nominal ascent trajectories • Performance maps of rockets • Optimization of non-nominal trajectories: missionization • Nominal Splash down of stages • Stages fragmentation analysis and splash down locations Guidance, navigation and control
- 16. GNC of a Small Rocket Guidance, navigation and control