10 missile guidance-systems
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Transcript of 10 missile guidance-systems
OBJECTIVE
• Understanding the mechanism behind working of a ballistic missile.
• Studying types of ballistic missiles missiles• Understanding concept of ballistics
Ballistic missile
• Rocket with a warhead• Follows a ballistic trajectory• Delivers one or more warhead to a predetermined target• Both guided and unguided• Guided during relatively brief periods of flight• Most of the trajectory is unpowered and governed by gravity and air
resistance if in atmosphere
PRINCIPLE• Works on Newton’s 3rd law of motion• Continuous Ejection of Hot Gases in one direction
causes a steady motion of rocket in opposite direction
• Operates on Brayton Cycle
Types of Ballistic
•Battlefield short range ballistic missiles [ 150 km]•Short range ballistic missiles [250-800 km]•Medium range [800-2400]•Intercontinental range ballistic missiles[5500 km]
Flight of icbm• Three parts:powered flight portion,free flight
portion &re entry phase • For srbm, two phases of icbm are employed• Launched from TELs,aircraft ,shi Ps ubmarines,• When in space and no more thrust is
required,missile enters free flight• For icbm ,highest altitude reached during free
flight is about 1200km
GUIDANCE SYSTEM • can be compared to the human pilot of an airplane• consists of an :
• ATTITUDE CONTROL SYSTEM• maintains the missile in the desired attitude • controls the missile in pitch, roll• damps out fluctuations that tend to deflect the missile from its ordered flight
path
• FLIGHT CONTROL SYSTEM• generate the orders to the attitude control system to maintain that path.
PHASES OF GUIDANCE
• 3 phases – boost, midcourse, terminal
BOOST PHASE
• Missiles are boosted to flight speed by booster component of propulsion system
• Lasts from the time missile is launched until booster burns up its fuel
• Missiles aimed in specific direction on orders from fire control computer
• This establishes line of fire along which missile must fly during boosted period
• At the end of boost , missile must be at pre-calculated point• Essential that it provides stability to missile
• Not always present; but when present it is the longest in time & distance
• Changes may be needed to bring missile onto desired course & to keep it on course
• Puts missile near target, from where reentry phase takes over control
MID-COURSE PHASE
Re-Entry vechile phase
• after propulsive phase ,Missile typically aligns , inertially stabilizes release a reentry vehicle on a trajectory towards a pre selected target
• the exterior of the rv is protected from aero thermodynamic heating by a T.P.S
• The aerodynamic shape configuration determines duration and flight path of rv
• This, in turn, affects the vehicle systems complexity and the heating loads on the payload.
CHARACTERISTICS
• have much longer range than would be possible for cruise missiles for same size.
• can travel extremely quick along there flight path• An ICBM can strike a target within a 10000km range in about 30 to 35
minutes• With speeds of over 5000m/s , these are much harder to intercept than
cruise.• High cost of production and maintenance• Follows ballistic path , hence attack detectable during boost phase
Types of propellantLIQUID PROPELLANTS- Two separately stored liquid propellant to produce thrust.
• Cyrogenic - USES VERY COLD AND LIQUIFIED GASES AS FUEL (lh2)AND OXIDISER. (lox)
• Distressing tendency to return to gaseous form unless kept supercool makes them difficult to store for long periods of time
• Not much used in military rockets
• Hypergolic - COMPOSED OF A FUEL AND OXIDISER THAT IGNITE WHEN THEY COME IN CONTACT WITH EACH OTHER.
• corrosive so special containers and facilities required
HYBRID PROPELLANT
• advantages of both liquid and solid rocket engines.• consists of a combustion chamber , packed with a solid chemical, . • two chemicals are hypergolic• liquid chemical is injected into the combustion chamber • ignition occurs and thrust is produced.
solid propellant•combustion chamber tubes packed with a propellant that contains both fuel and oxidizer blended together uniformly•relatively stable therefore it can be manufactured and stored for future use•. Solid propellants have a high density and can burn very fast•insensitive to shock, vibration and acceleration
FUTURE AND LATEST DEVELOPMENTS
AGNI V1:
ICBM TYPE NUCLEAR WARHEAD FOUR STAGE SOLID FUELED CAPABILITY TO BE LAUNCHED FROM SUBMARINES AND FROM LAND
BASED LAUNCHERS OPERATIONAL RANGE –( 8000-12000).
AGNI V:
3 STAGE SOLID FUELED RANGE 5500 to 5800KM
THANK YOU