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--- projects:ukhas_glider_project:methods_of_control [2007/08/22 10:57] – laurenceb
+++ projects:ukhas_glider_project:methods_of_control [2008/07/19 23:33] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
 ====Rogallo====
+===Flight code===
+ First version now ready, written in bascom basic
+ [[Master|Master AVR]]
+ [[Slave|Slave AVR]]
 ===Simcode===
 Using the oscillation observed under proportional control, a simple ode based model can be tested.
-{{projects:ukhas_glider_project:rogallocomparison.png|}}
+{{projects:ukhas_glider_project:rogallocomparison2.png|}}
-It can be sen that rogallo yaw behaviour is quite complex, however, there may have been significant wind disturbance during the test. The second fit (yellow) uses a yaw_rate^2 damping term, wheras the first (purple) uses an aerodynamic damping term proportional to yaw_rate . It can be seen that yaw_rate^2 gives better results, so this will be used in the kalman filtering. Interestingly, the servo gain factor, which describes how a given servo displacement effects yaw acceleration (simple linear approx) has to be significantly larger (2.4) in the second fit than in the first. The nonlinear damping significantly decreases the frequency of oscillation.
+It can be seen that rogallo yaw behaviour is quite complex, however, there may have been significant wind disturbance during the test. The second fit (yellow) uses a yaw_rate^2 damping term, wheras the first (purple) uses an aerodynamic damping term proportional to yaw_rate . It can be seen that yaw_rate^2 gives better results, so this will be used in the kalman filtering. Interestingly, the servo gain factor, which describes how a given servo displacement effects yaw acceleration (simple linear approx) has to be significantly larger (2.4) in the second fit than in the first. The nonlinear damping significantly decreases the frequency of oscillation. The simcode is very simple, based on the code on the [[projects:mihab:glider|MiHAB glider page]]
 ===Data recording with proportional control===
-Work is now underway on fine tuning the Rogallo control loop.\\ Data recording at 5 samples per second:
+Work is now underway on fine tuning the Rogallo control loop.\\ Heading offset data recording at 5 samples per second:
 {{projects:ukhas_glider_project:rogallonowind.png|}}
+A Fourier transform, the peak is at 0.17857 Hz or 5.6 seconds period
+{{projects:ukhas_glider_project:fft.png|}}
 {{projects:ukhas_glider_project:5hz.png|}}