EAS458- Guidance and Control entire chap

Avionics

1. EAS458- Guidance and Control Lecture by S Kishore Kumar

2. Introduction

3. The application of control theory to aerospace may be divided into four areas. Flight Planning : The determination of a nominal flight path and associated control histories for a given flight vehicle to accomplish specified objectives with specified constraints. Navigation: The determination of a strategy for estimating the position of a vehicle along the flight path, given outputs from specified sensors. Guidance: The determination of a strategy for following the nominal path in the presence of off-nominal conditions, wind disturbances, and navigational uncertainties. Control: The determination of a strategy for maintaining the angular orientation of the vehicle during the flight that is consistent with the guidance strategy, and the vehicle, crew, and passenger constraints.

4. Areas Guidance   refers to the determination of the desired path of travel (the " trajectory ") from the vehicle's current location to a designated target, as well as desired changes in velocity, rotation and acceleration for following that path. Navigation  refers to the determination, at a given time, of the vehicle's location and velocity (the " state vector ") as well as its  attitude. Control   refers to the manipulation of the forces, by way of steering controls, thrusters, etc., needed to execute guidance commands while maintaining vehicle  stability.

5. GNC systems GNC systems are found in essentially all autonomous or semi-autonomous systems. These include: Autopilots Driverless cars like  Mars rovers  or those participating in the  DARPA Grand Challenge Guided missiles Precision-guided  airdrop  systems Reaction control systems  for  spacecraft Spacecraft   launch vehicles Unmanned aerial vehicles Auto-steering tractors

6. Navigation: The Process of safely and efficiently directing the movements of a vessel from one place to another . https://www.youtube.com/watch?v=ZZ0_i6XboSU

7. Types of Navigation 1. Piloting ( Coastal ) Navigation 2. Dead Reckoning Navigation 3.Celestial Navigation 4. Electronic Navigation

8. Piloting Navigation Piloting Navigation- This is the process by which ships position found usually at set of interval of time , by taking three compass bearing is fixed, prominent and identified charted objects. These bearings, when corrected for deviation and variation are plotted on charts and the vessel position at the time is found.

9. Dead Reckoning

10. The products derived from these variables, when adjusted by wind speed and velocity, are heading and GS. The predicted heading takes the aircraft along the intended path and the GS establishes the time to arrive at each checkpoint and the destination. Except for flights over water, dead reckoning is usually used with pilotage for cross-country flying. The heading and GS, as calculated, is constantly monitored and corrected by pilotage as observed from checkpoints.

11. Celestial Navigation It is to measure the vertical angle of the sun, moon and planets or stars above the horizon. A calculation based on DRP, will yield the distance towards or away the celestial object from that position.

12. Electronic Navigation This form of navigation is any navigation undertaken using electronic navigational aids. It is an important NAV understand the limitations and error that these systems are prone to. These includes A. LORAN C B. RADAR C. Transit satellite navigator D. GPS

13. GNC

14. GNC BLOCK DAIGRAM

15. GNC ELEMENTS

16. NAVIGATION

17. Spacecraft Control

18. Attitude control

19. Broad Control System Categories

20. GNC for launchers

21. To be Continued next session