Dave Cooper (UAB) Ifju, Jenkins, Ettinger, Lian, Shyy (2002) Size - PowerPoint PPT Presentation

Dave Cooper (UAB)

Ifju, Jenkins, Ettinger, Lian, Shyy (2002)  Size of the order of insects or birds  Propulsion ◦ Fixed wing ◦ Rotary wing ◦ Flapping wing ◦ Combination Jones, Bradshaw, Papadopoulos, Platzer (2005)

 Applications ◦ Defense ◦ Search and Rescue ◦ Surveillance  Examples ◦ DelFly micro, TU Delft (3g/10cm) ◦ Nano Hummingbird, AeroVironment (19g/16cm) ◦ UAB (10g/20cm) ◦ Wright State (12g/20cm)

 2 pair of Counter-oscillating flexible wings  Clap and fling interactions

 How much power is required?  What are the forces?  How do the input parameters affect the performance? ◦ Wing geometry ◦ Frequency

 Morphing mesh  Rigid body assumption ◦ Less expensive ◦ Is it valid?

 Morphing considerations ◦ Poor cell quality ◦ Negative volume cells ◦ Computation time  Solutions ◦ Minimum space between wings (6mm) ◦ Pre-Morphing mesh ◦ Limit number of cells

 2-components ◦ Flapping  About Z-axis  Mechanism parameter driven ◦ Pitching  About wing leading edge  Specified

 Input parameters ◦ Linkage lengths ◦ Drive gear rotational speed 0.8 0.6 ad) 0.4 (rad 0.2 le ( Angle 0 -0.2 -0.4 0 0.01 0.02 0.03 0.04 Time(s) s)

1 Interacti 1 tion on 1  Specified 0.5 e (rad) d) 0 Angle ( ◦ Avoiding negative An -0.5 volume cells -1 ◦ “Natural” motion 0 0.01 0.02 0.03 0.04 Ti Time me(s) ◦ Timing and max pitch are adjusted 2 I Interacti tions ons 1 0.5 d) e (rad) 0 Angle ( An -0.5 -1 0 0.01 0.02 0.03 0.04 Ti Time me(s)

1 I Interacti tion on  Time derivatives 250 d/s) ◦ MATLAB calculated peed (rad/ 150 numerical derivatives speed 50 Angular s  Tables generated -50 -150 An 0.00 0.01 0.02 0.03 0.04 Ti Time me(s) Fla Flappi pping 2 I Interacti tions ons 100 200 eed (rad/s) d/s) 150 peed (rad/ 50 100 speed 50 speed 0 0 Anglular s Angular s -50 -50 -100 -100 -150 An An 0.00 0.01 0.02 0.03 0.04 0.00 0.01 0.02 0.03 0.04 Time Ti me(s) Ti Time me(s)

 11 field functions ◦ 1 Flapping table interpolation ◦ 2 Pitching table interpolation ◦ 4 Wing axis tracking ◦ 4 Wing motion compilation

 4 motions ◦ 1 for each wing ◦ Modified center of rotation coordinate systems ◦ Direction and magnitude of vector field functions

 Qualitative verification ◦ Does it look natural?

Frequency (Hz) Maximum Pitch (deg) Avg Thrust (N) Avg Power (W) 30* 30* 0.08* 0.65* 35* 30* 0.11* 1.02* 35* 45* 0.15* 0.79* 28* 45* 0.09* 0.33* 28 45 0.14 1.05 23 45 0.09 0.56 *Simulations conducted using only two wings and assuming symmetry.

0.5 0.4 0.3 (N) 0.2 Thrust ( 0.1 Th 0  Thrust -0.1 ◦ Average: 0.09N -0.2  Moments about 0.015 Z-axis 0.01  Power (N-m) m) 0.005 ◦ Average: 0.56W ment ( 0 Mome  No Appreciable Hysteresis -0.005 Mo effects -0.01 -0.015 0.5 0.3 ower (W) (W) Powe 0.1 -0.1 -0.3 0.00 0.02 0.04 0.06 0.08 0.10

 Dependencies ◦ Thrust ~ Freq 2 ◦ Power ~ Freq 3 ◦ Thrust ~ Wing Area ◦ Power ~ Wing Area  Conclusion ◦ Trading Wing Area for Frequency results in a net gain

Ifju, Jenkins, Ettinger, Lian, Shyy (2002). Flexible-Wing-Based Micro Air Vehicles. AIAA 2002-0705  Jones, Bradshaw, Papadopoulos, Platzer (2005). Bio-inspired design of flapping-wingmicro air vehicles.  The Aeronautical Journal, Aug 2005 DelFly micro. http://www.delfly.nl/  AeroVironment. Nano hummingbird. http://www.avinc.com/nano  Ohio Center of Excellence for Micro Air Vehicle Research at Wright State University.  http://www.engineering.wright.edu/mav/