3. 1.FLAPPING WING MAV:
• Birds taught humans to fly.
• Leonardo da Vinci’s Studied the bird flight.
• Emerged from the dream of mastering the
flight of the natural fligher.
• Complexity of the insect flight
• Bird Flight- Ornithopter.
• Insect flight- Entomopter.
• Scientists concluded that ornithopter flight
is efficient than static wing flight
because wing alone produces lift as well
as thrust.
• 15 cm mark by DARPA
4. Wing Kinematics:
• Basic Terminology:
• Consists of 3 axes
1. Flapping axis.
2. Pitching axes
3. Lead lag
5. Forces generated by flapping wings:
Divide into two strokes:
• Down stroke
• Up stroke
• Induced flow is maximum near the tips.
• The Angle of attack is varying along the span.
• For flexibility, the angle of attack keeps varyin
with the stroke.
8. 2.Fluid dynamic modeling:
• Using BLADE ELEMENT ANALYSIS.
• Modeling reality on paper is very difficult.
Assumptions :
• Wings are made of flexible membrane attached
with spar at leading edge and wing form is ha
elliptical.
• Only flapping would be induced by the power
plant with equal up/down flapping angles.
• The front spar will act as pivot for passive
pitching movement, caused by the
aerodynamic/ inertial loads.
9. • The flow is assumed to remain
attached.
• Both flapping and pitching
movements are taken as sinusoidal
functions with certain amount of lag.
• Upstroke and down strokes have
equal time duration
11. 3.Parametric Study and Results
A MATLAB code has been written and th
Results are in graphical format.
•Span=40cm
•Root chord=10cm
•Mass= 12 gms
And other minor values are assumed.
•The graph starts from down stroke and
to up stroke.
•Time is converted dimensional numbers.
12. Inputs required to solve:
•Forward Speed
•Flapping Frequency
•Total Flapping Angle
•Incidence Angle of the Fuselage
•Maximum Pitch Angle
•Lag Between Pitching and Flapping
• Span wise strips and time steps.
20. 4.Conclusion:
•Lift of an ornithopter is most influenced by the
incidence angle and forward speed but least
affected by flapping frequency.
•Thrust of an ornithopter is most affected by
flapping frequency and forward speed but least
influenced by incidence angle.
•·The drag force increases with increase in forwa
speed, incidence angle, and flapping frequency.
•·The increase in total flapping angle increases a
the forces but the effect is marked on drag force.