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Old 06-04-2012 | 08:59 PM
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Aero65
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From: Honolulu, HI
Default RE: New 3 axis stabilization in testing

Hey Barry

Thank you sir, I really like this unit it has a lot of features and works well. You gotta see this thing recover from inverted just too funny, hit the switch and its upright and level like now lol it's just too cool.

Here are my test results from Sunday.

I was able to load up the PC interface for the Guardian and do some additional testing this weekend. Sorry no additional video my friend was out of town that usually videos.

It was a typical windy day at the field (Kaneohe Bay)

03 16:57 NE 10 G 22 10.00 Partly Cloudy FEW028 SCT050 79 70 74% NA 82 30.08 1018.0
03 15:57 NE 13 G 20 10.00 Overcast FEW028 OVC055 78 67 69% NA 80 30.08 1018.2
03 14:57 NE 15 G 24 10.00 Partly Cloudy SCT027 SCT046 86 72 63% NA 92 30.09 1018.5
03 13:57 NE 12 G 18 10.00 Fair CLR 82 66 58% NA 84 30.11 1019.0
03 12:57 NE 13 G 21 10.00 Fair CLR 80 64 59% NA 82 30.13 1019.6
03 11:57 NE 13 G 21 10.00 Mostly Cloudy SCT030 SCT038 BKN050 80 64 59% NA 82 30.14 1020.2

Test 1: Ability to change, servo update rate with PC software. Most digital servos update at around 250 Hz, most analog servos about 50 to 70 Hz (Guardian default 50 Hz, the Futaba GY-401 analog setting is 70 Hz). In my F-4D I have Futaba S9156 servos on the elevons, and a JR DS368 servo on rudder (DS386 = 300 Hz update speed). I did not know the Futaba update speed but knew it was at least 250 Hz, so I set the Guardian at 250 Hz.

You must be careful when changing this setting you must use the lowest servo refresh rate of all you servos connected to the Guardian. If you had 2 digital servos and 1 analog for instance you would need to set it at 50 Hz, the digitals will work fine at this setting. If you try and run an Analog servo at a higher refresh rate than it can handle it will burn out.

Results: Two weeks ago, at 50% master gain the F-4D oscillated in roll, now at 250 Hz I was able to fly at full throttle at that gain without oscillation. Another effect was now my roll control was much more dampened and the overall effectiveness of the gyro was better. I did feel with the increased gyro effectiveness it felt like you had to really push the controls, this is where direct rate would be great.

Test 2: 2D mode recovery from unusual attitudes.

Method 1: Roll inverted recovery. Ok put Guardian in off position, then rolled the F-4D inverted (1.5 split S high just in case) activated 2D, it very, and I mean very quickly rolled upright and level no overshoot totally impressive, I will get video of this next week.

Method 2: Pitch straight up. Guardian off pulled F-4D into vertical climb turned 2D on plane pushed over leveled out non issue.

Method 3: Vertical dive. Guardian off pulled F-4D into loop on backside of loop pointing straight down turned 2D on plane pulled up leveled out non issue.

Conclusion: Testing went normally, the increased resolution that was available to the digital servos when you turn up the update speed was impressive, settings that resulted in oscillations at 50 Hz were rock solid at 250 Hz. The decreased control authority due to the Guardian working better really made me want to test direct 3D rate but did not have the time to set it up properly so that will have to wait for the upcoming Sunday.