Guidance, navigation and control

the explanation provided using many references

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