Weird 'event' happened today, but SK720+GPS saved the day

[remoterecon]

Hi Guys,

I had a very strange event happen today. I had quite a few flights on my Logo550SE with SK720 + GPS. I'm getting back into helicopters again and have been loving the features of the 720 to keep my heli safe and sound.

For this flight, I had a soft floor set and I was flying with self level (100%) with CS +inverted.

Near the end, I had an 'event' that I'm having a hard time parsing. From my recollection, the heli just started rolling into something that looked like a somersault. It seemed like an uncommanded input, but it's hard to say.

All that said, it's very possible that the heli started to roll and I corrected the wrong way, causing it to roll inverted and pitch forward, with me shivering like a little girl at the sticks thrashing to save it.

Despite the gallon of urine that had puddled below me, the SK720+GPS dutifully corrected and 'saved' the helicopter from certain death. Yay Skookum!!

That said, it's making me a bit nervous right now given the fact that I'm 80% sure that the Logo just spasmed on its own.

Here's the log from that flight.

https://www.dropbox.com/s/2qnbr22gqc...LOG50.SKL?dl=0

The only thing I can surmise is that I hit the floor, but it wasn't sure what to do, and the sequence of events were it choosing 'poorly' until it figured out the proper save. I was close to the floor when this happened.

Art/Skookum team: It would be great if the GPS commands were part of the event log. The viewer shows switching of the cyclic modes, but doesn't show when the bail outs kick in, etc.

Thanks!!

[Xrayted]

Originally Posted by remoterecon

Hi Guys,

I had a very strange event happen today. I had quite a few flights on my Logo550SE with SK720 + GPS. I'm getting back into helicopters again and have been loving the features of the 720 to keep my heli safe and sound.

For this flight, I had a soft floor set and I was flying with self level (100%) with CS +inverted.

Near the end, I had an 'event' that I'm having a hard time parsing. From my recollection, the heli just started rolling into something that looked like a somersault. It seemed like an uncommanded input, but it's hard to say.

All that said, it's very possible that the heli started to roll and I corrected the wrong way, causing it to roll inverted and pitch forward, with me shivering like a little girl at the sticks thrashing to save it.

Despite the gallon of urine that had puddled below me, the SK720+GPS dutifully corrected and 'saved' the helicopter from certain death. Yay Skookum!!

That said, it's making me a bit nervous right now given the fact that I'm 80% sure that the Logo just spasmed on its own.

Here's the log from that flight.

https://www.dropbox.com/s/2qnbr22gqc...LOG50.SKL?dl=0

The only thing I can surmise is that I hit the floor, but it wasn't sure what to do, and the sequence of events were it choosing 'poorly' until it figured out the proper save. I was close to the floor when this happened.

Art/Skookum team: It would be great if the GPS commands were part of the event log. The viewer shows switching of the cyclic modes, but doesn't show when the bail outs kick in, etc.

Thanks!!

All of the GPS activation info, time it was activated in flight, number of sats being seen, speed and altitude are part of the log as well as all of your other channel outputs. You just have to purchase the optional Pro data viewer license in order to see it all. http://www.skookumrobotics.com/produ...ta-viewer-pro/

I've had one weird episode with mine once when using the soft deck. I was doing a fast backward flip, and the heli touched the deck right as I started to flip the tail up and over to do the loop. I was moving fast enough that i was able to get the heli flipped over before the rescue could completely grab it from me.

The rescue finally grabbed the heli and flipped it over upright, but it went into a violent elevator rocking back and forth while continuing to climb well above the rescue hold position. I just flipped back into manual and took it back and all settled down.

I concluded that it is possible for strange things to happen if the right circumstances are there, but I'm not worried about it and its operated normally every other time. There was never any danger of me crashing, and I prefer the hard deck, as the SD seems to grab the heli at very random times for me, many times well above the set limit.

I once had it grab my heli when doing a big power loop, and I was at least 20m or more in the air and the SD was set to 10m. My assumption is that the very fast downward speed in power loops fools the system into thinking its going to hit the deck very soon since it pre calculates the distance it has to work with using that mode, however it doesn't know you are in a loop and will be leveling out soon. Basically my theory is it assumes I'm going to stay on the same nose down fast trajectory right into the ground unless it initiates the rescue high up to stop it.

[remoterecon]

Thanks Xrayted! Yeah, your experience went through my mind as well. I remember reading your post when it happened.

I have the full paid, licensed viewer. I can see the altitude and other information there, but for events, all I see is:

Event at -19.9 seconds: SK720 initialized in Cyclic 1 and Tail 1

Event at 9.4 seconds (0:09): Switched to Cyclic 2

Which is incomplete. The GPS module definitely kicked in and rescued the heli, but there's no mention of it here. I turned on the Soft Floor somewhere around 10 seconds but also, no mention of it in the event log.

Health information is:

Number of missing receiver data frames from Sat Rx A: 3
Number of missing receiver data frames from Sat Rx B: 3

What's interesting is I get a lot of not enough GPS satellite warnings, but the GPS is in full view of the sky, etc. Not sure what the threshold is for that, or what I could do to make it better, etc.

Thanks!!!

[Xrayted]

Originally Posted by remoterecon

Thanks Xrayted! Yeah, your experience went through my mind as well. I remember reading your post when it happened.

I have the full paid, licensed viewer. I can see the altitude and other information there, but for events, all I see is:

Event at -19.9 seconds: SK720 initialized in Cyclic 1 and Tail 1

Event at 9.4 seconds (0:09): Switched to Cyclic 2

Which is incomplete. The GPS module definitely kicked in and rescued the heli, but there's no mention of it here. I turned on the Soft Floor somewhere around 10 seconds but also, no mention of it in the event log.

Health information is:

Number of missing receiver data frames from Sat Rx A: 3
Number of missing receiver data frames from Sat Rx B: 3

What's interesting is I get a lot of not enough GPS satellite warnings, but the GPS is in full view of the sky, etc. Not sure what the threshold is for that, or what I could do to make it better, etc.

Thanks!!!

That is strange. You should see all the relevant GPS info as well in that same event log. Does your log software say "date viewer Pro" on the top left edge of the software box when open like the photo I attached? It would have to in order for you to map the GPS speed and altitude, so its strange there is no record of your rescue. The GPS lines within the event log will say something like "begin self leveling" "Auto pilot engaged Soft deck at XXX seconds" "autopilot disengaged", etc. Ive had issues in the past with doing say 8 flights, but only having 5 logs when I get home. Reformatting the flash drive in the unit via the Utility dropdown in the software clears this strange behavior up for me when this starts to happen.

I don't have any current flight logs of mine saved at the moment to post up what I see in my logs. The not enough GPS sats warnings are pretty common. The system sees a lot of sats, but some are weak and they come and go rapidly during the flight.

The heli needs a threshold set to maintain the ability to rescue from any inverted 3D position. You can also see the number of sats in real time as one of your corner menu choices during the video flight payback and see this threshold being crossed from time to time. For me, it seems the warning comes when the number of sats drops below 6-7, but these are only momentary drops. I've also learned where the "dead zones" are where I fly, as I seem to always get the green light when passing through a particular area of the field.

Open the software and under Preferences chose flight log playback settings, and you will see many choices for what can be shown in the corners during playback. Its interesting to see the sat lock status in real time during the flight and cross reference them with the warnings.

[SpeedTape]

I had a look at the .KML file in Google Earth. I attached the file below as a .txt file - change the extension to .KML if you want to open it in Google Earth.

It seems to show that the system had a good sense of which way was up because the little 3D model of the heli in Google Earth seems to be oriented correctly for the direction of flight.

If you click on the vertices of the flight route path, you can also find locations where it was in soft-floor mode.

The event log created by my version of the data viewer also does not show the system being switched into soft-floor mode. I agree that is weird, especially since the data viewer seems to be aware that the heli was switched into soft-floor mode (given that it was the data viewer that created the Google Earth KML file that I attached to this post). Sounds like there might be a bug in the event log.

[remoterecon]

Awesome guys. Thanks!

Digging through my flight logs, some of them actually do show more fine grained data on what was switched on when, so I agree it's likely a display problem.

Xrayted: You rock and I really appreciate your posts (you too SpeedTape!). I do in fact have the pro version, mine just seems to be bugged out. It's folks like you (and Georgi) that make this hobby so much better.

I'll try reformatting the card as a precaution and one extra step to help it write the information it needs.

Looking at the rest of the logs, I'm not happy with what I see on the servo Bus Voltage. There seems to be a lot of ripple in the voltage, and there is a massive dip around 57 seconds, but I'm not sure if that's just an instrumentation error. I've never been happy with Castle Creations BEC's so I'll switch to a LiFe battery for the moment to see if this improves. I'm not doing any hard 3D, just the odd flip and roll, so weight is not a factor short term.

Art: It sure would be nice to be able to export the raw data from the Pro Data Viewer, so I can have a look at the numbers directly, or be able to plot it out in another visualization engine. Just a thought for a future release. I'll send the log file to info@sk... as well, so you can have a peek.

Thanks again all!