1. Team One Dynamics and Control PDR 2 10 March, 2005
Speakers
Mike Carpenter
Josh Mook

2. Objectives Controllability Considerations Control surface size
Design Feedback Control System
Yaw rate feedback to the rudder
Dynamic models for block diagram
Root locus of the control system
Nominal feedback gain

3. Current Sizing Wing Loading = 0.59 lbf/ft2 Weight = 1.70 lbf
Wing Span = 4.21 ft
AR = 6.2
Wing Area = 2.85 ft2
H-Tail Area = 1.13 ft2
V-Tail Area = 0.33 ft2

4. Control Surface Sizing
Based on Historical Data
Aileron Surface Size
Wanted to Cover Most of Second Half of Wing Section
Longer Moment Arm for Aerobatic Maneuvers
Elevator Surface Size
Larger Size Chosen to Insure Pitch Control
Large Chord Percentage Due to Elevators not covering Entire Span
Rudder Surface Sizing
Larger Size Chosen to Insure Yaw Control

5. Control Surface Sizing
Rudder
Aileron
Elevator

6. Elevator Deflection
Displays change in CL for varying elevator deflection
Compared to Cessna 414
Provides adequate control authority through moment about CG

7. Piezoelectric Gyro Ikarus Tele-Gyro Mass: 0.87 oz
Voltage: 3.5 – 12 volts
Control Sensitivity from Radio
Automatic Fading
Reverse Switching
Signal
Piezo Gyro
Signal +/- Rate Corrections

8. Dynamic Model Symbolic aircraft transfer function
Numerical values for physical constants = = = = =

9. Feedback Control Block Diagram
Yaw rate feedback to the rudder to change yaw damping

10. Dynamic Models Aircraft transfer function
Rate gyro transfer function: 1
Actuator transfer function: 1
Control law :
Control Law Laplace Transform:

11. Longitudinal Stability
Root Locus for longitudinal stability
All poles in left-half plane
Stable pitch control
Poles =
e-005 i i
Poles
Xxxxxxx
Phugoid
Short Period

12. Feedback Control Poles = Lateral-Directional feedback 0.30452 i i
Lateral-Directional feedback
Positive Gain
Negative Gain
Stable at zero gain except for spiral mode which is slightly unstable--- alert pilot to
Can have basically any negative damping, but don’t want anything too large because we don’t want a slow response.
Can have a slightly positive gain, but not too much, or the aircraft will become unstable.
Examine the effects of changing the gain
xxxxxxx
Spiral Mode
Dutch-Roll
Roll

13. Results Aircraft is naturally stable in all modes except spiral mode.
Spiral mode is only slightly unstable.
Feedback chosen to control lateral-directional stability Dutch-Roll mode.
Results from FlatEarth code verify results obtained from team’s matlab code.

14. Team One
Dynamics and Control
PDR 2
10 March, 2005