Date: 11/23/10 [[BR]]
Location: Tri Valley [[BR]]
Aircraft: Loki [[BR]]
Pilot:  Garrison Hoe [[BR]]
Flights: 7 Loki[[BR]]

[source:/trunk/FlightData/2010_11_23 Link to Flight Data]

Garrison, Andrei, and myself took Loki to UMORE Park today. Weather was good; sunny, SE winds at less than 5 MPH, temps around 20-25F. Any higher winds would make windchills hard to deal with. The grass surface was completely snow covered, but a very hard crust had formed that we could drive on. The aircraft had no issues taking off and landing on this surface. It did appear that there was some plowing done on the access road, but this may be an issue with deeper snow cover.

The objectives for the deployment were:

1. Run system ID programs for Arda, Andrei, and Rohit (respective team leads)
2. Test out new Free Wave modems.

We completed 7 flights; the new Free Wave modems worked great. 


Loki Flight 27: Arda aileron/rudder PID; During ground checkout, the motor was set to zero under auto mode. (was fine under manual control). Inspection of the code revealed that the throttle was not properly set in the new system ID sections. This was corrected, but resulted in a 20 minute delay. This program alternated between aileron chirps and rudder chirps from 0.1 to 6.0Hz. The flight went well; aileron amplitude seemed somewhat low, but the aircraft normal remained on trim. The rudder had plenty of amplitude (maybe too much) and the large initial input resulted in a spiraling flight condition. 

Loki Flight 28: Andrei elevator PID; This program alternated between low frequency (0.06 to 0.3Hz) and high frequency (0.3 to 7Hz) elevator chirps of +/- 2deg and +/- 4deg respectively. We noted during the ground check that the high frequency input appeared to degrade at the higher frequencies- this may have been a result of running the control code at 25Hz instead of 50Hz. Nonetheless, the flight went ok; the phugoid mode was observed during the low frequency input and pitch oscillation was observed in the high frequency inputs.

Loki Flight 29: Andrei throttle PID; This program alternated between a low frequency (0.06 to 0.1Hz) and slightly higher frequency (0.1 to 0.2Hz) throttle chirps of +/- 10%. The flight went good; noticeable speed changes were observed in both inputs.

We attempted to fly Rohit's aileron/rudder chirps next, but noted that the motor was set to zero during auto mode. We did not have the source code to attempt a fix.

Loki Flight 30: elevator doublets; +/-5 deg, 6 second period. Three repeats for validation data.

Loki Flight 31: throttle doublets; +/-20%, 6 second period. Three repeats for validation data.

At this point we warmed up in the car and examined the data. Andrei requested we modify the bandwidths of his elevator chirps in an effort to improve the high frequency signal quality. We also increased the aileron amplitude of Arda's chirps.

Loki Flight 32: Andrei elevator PID; This time the low frequency was 0.1 to 0.4Hz and the high frequency was 0.4 to 5Hz. Amplitudes were the same. The signal quality did not appear to improve. 

Loki Flight 33: Arda aileron/rudder PID; Aileron amplitude +/- 4deg.

By this point we were actually running out of daylight. We did notice reduced airplane climb performance, likely due to the batteries not performing as well.

We were far too rushed this morning, and did not have enough time to test every program in PIL simulation. I was able to test most the programs in the airplane; however, since we normally do this with the motor unplugged, I didn't catch the motor issues until we were in the field. We can try again next week.

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