MICRO AIR VEHICLES
WHAT ARE MAVS(AV’S)?
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Multi functional, militarily capable, small flight
vehicles.
size should be less than15cms.
Reynolds's no < 10^5.
For a Primarily intended and developed for
defence applications.
WHY MAV’S? WHY NOT
SOMETHING BIGGER?
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Keeps security personnel out of harms by
providing situational awareness right down to
platoon level.
Direct connectivity
Can be individually controlled
Can be used for a wide range of new
missions _ (even unthought-of before)
APPLICATIONS
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Reconnaissance
Surveillance
Defence applications
Weather forecast
Wildlife study
&photography
Crowd control
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Targeting
Border surveillance
Traffic monitoring
Tracking criminals &
illegal activities
Biochemical sensing
inspection of pipes
OVER THE HILL
RECONNAISSANCE
MOTHER BIRD APPROACH
Tracking of chemicals
MAIN SUB SYSTEMS
1.
FLIGHT CONTROL
2.
PROPULSION SYSTEM
3.
COMMUNICATION SYSTEM
4.
GUIDANCE&NAVIGATION
MAV flight regime compared with
existing flight vehicles
FLIGHT
CONTROL&AERODYNAMICS
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Reynolds's no:= inertia force/viscous force
Low Reynolds's no: flights may have lift to drag ratio of 5
to 10.
The best aspect ratios usually lie between 1&2
Angle of attack should be 5-12° for good endurance.
If angle of attack <5, low aerodynamic efficiency
Endurance=/power requirement
For optimal endurance the mav should fly at7°
ACTIVE OR PASSIVE CONTROL
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Use strategies using MEMS
Create &install tiny sensors
miniature actuators
Flow character controlled by sensor arrays
Flexible membranes or micro flaps to affect
the flow as required
Micro motors piezoelectric devices magneto
elastic ribbons
WING DESIGN AND
FABRICATION
 Types of wings
 wing shapes
 Composite materials,
 Carbon fibres
 carbon fibre-balsawood sand
witches are commonly used
Inflatable wing
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Distend (fill) with air or gas
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Application in UAV, military
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To stow the wings
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Can be launched from gun or aircraft
Advantages of aircrafts with
inflatable wings
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Can be packed to 1/10 of original size
Low mass
Low power requirements
High reusability
It can be steered, accelerated, and
decelerated in level flight.
High stability and control
High lift and slow landing speed
Experiment on inflatable wing
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Experiment conducted
using I 2000
It was launched from
800-1000 feet
Inflatable wings comes
out in 1\3 sec
Successfully controlled
the launch,flight and
landing
Controlling of wing
 by using piezoelectric
material
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actuator can be quartz and substrate can be
aluminum or steel
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inflatable wings has smooth surface so low
value of skin friction
I-2000 & X-24A
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Both have inflatable
wing
I-2000 is UAV
X-24A is manned
Disadvantages
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They are not self powered
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Cannot launch from ground
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There are chances of air bag buckling
PROPULSION SYSTEM
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Propulsion system alone consumes 90% of total
power
Lithium alkaline batteries
IC engines
Reciprocating chemical muscle
Lithium battery that recharges using solar
energy and fuel cells are also future prospects
Self consuming systems
COMMUNICATION SYSTEM
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A video/still camera,
various sensors,
micro processors,
Transducers
& an omni directional antennae
GUIDANCE AND NAVIGATION
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A combination of GPS+inertial sensing is
ideal
Geographical information system to
provide a map terrain for infrastructure
would be great
Pressure sensors
MAV SYSTEM INTEGRATION