Parrot Drone crash – SOLVED!… Pic Watchdog Emergency.

Had a crazy crash with my Parrot AR Drone while I was testing some ideas for the Parade of the Lost Souls (you can see my test footage at left).  This is how I assessed and fixed it.

I hit a street light about 25 or 30 feet up. Down it came crashing. Why, oh why, did I listen to the passing child who insisted I try out the outdoor hull? I usually use the indoor hull at all times because I just think it will help the thing last longer. But no, it came straight down on the corner and broke a rotor gear in half, and broke the pin.

Replacing the hardware was easy enough. I had a set of gears and pins already from NCIX, which I’d already used to replace one similar bit of damage.

However, when the thing initially crashed, it was in the middle of recording video. When I picked it up, the AR Freeflight app was asking me “Start video repair?” or words to that effect. If you know the actual error message I’m referring to, could you post it below?

I said “Yes” to this query, and things starting spinning on the iphone screen – but then it said “Battery too low.”

I had no other battery with charge remaining, but I tried quitting and restarting the app a couple times with the exact same problem.

When I finally got a new charged battery into the thing, instead of the “start clip repair?” or whatever, it said “Pic Watchdog Emergency.” The battery read zero, and I had intermittent access to the “home” button (it would appear and reappear as I tried to take pictures or record video in the app). The takeoff button on the iphone was green, but all four lights on the copter motors were red.

I tried doing a reset with the drone’s reset button, took the whole thing apart to see if all the connections were good (using Tom Strong’s excellent videos), uninstalled and re-installed the app, rebooted my phone …. all to no avail.

So I did another restart, and finally got a weird thing happening with “Updating Media Gallery.”  That happens every time the drone starts up, but now it was acting weird – kept crashing the app halfway through the progress bar.  Did it several times, and lo and behold – after several tries and crashes, there were some new videos in the media gallery, that had been missing previously – the video of the actual crash, and the video I shot right after the crash which hadn’t seemed to actually record at the time.

I hooked my iphone to my Hackintosh, downloaded these videos and deleted them from the phone.  Next time Freeflight started, it did so quickly and without mishap…  but still drone no fly.

I went through all the proper steps – uninstalling the app, rebooting the phone, even reset the phone to factory settings and reinstalled the app.  Still no drone fly love.

So then I guessed it was a hardware issue.  Everything worked fine – the camera, recording functions etc – but “pic watchdog emergency” and no response to the takeoff button.

So I actually called AR Drone Support who walked me through some checks, and finally they said it was either the navigation board or the mainboard.  Damn!  They had never heard of the “Start Clip Repair?” error either.

Navigation board is cheaper (C$69.99 vs C$109.99 for Mainboard), and seems to contain more fragile parts: the gyros, the sonar, the stuff that determines attitude and altitude etc.  That’s my candidate for damage after a crazy fall.  None of the parts had visible damage, but I couldn’t tell if certain connectors were supposed to be soldered together or not.

In this photo of a Mainboard (which Parrot support sent me – Boss!!!) there are some connectors at the top right, just where it says 1J1600.  That’s where the Navboard connects to the Mainboard.  The pins aren’t soldered down, but when I connected the two boards, it seemed clear to me that there was a good solid contact, and no room for wiggle.  Parrot support thought the opposite; the lack of soldering there, they said, meant I should replace the Mainboard.

But my instincts were the opposite:  Nav Board seemed more inherently fragile VS a sort of guess that maybe the soldering was broken, despite no visible evidence that the main and nav boards had suffered some kind of shear or jarring.  I mean, the two parts are screwed down together really solid; for them to yank sideways and damage that connector would have meant yanking all the screws and anchors as well, no?  No?

Go with your gut, Flick!  And your gut says buy the cheaper part!

I also noted that the parts at NCIX were no returns.  Even if unopened.  So I had to get it right, or sit on a pricey part.  Calling all over town, I found the Source had parts in stock at their Toronto warehouse – and their guarantee would be beyond my Parade of Lost Souls Show.  NCIX had the same but with a faster guarantee.

Eventually got the part (NCIX messed up my order but then radically sped up to solve it.  I replaced only the part with the two sonar thingies – the Nav Board is in two parts.  I figured, once again, the part that looks more fragile IS more fragile, and so only replaced that.  Lo and behold, the drone flew again!

The old Nav Board part went on my Steampunk Cowboy Halloween costume.  It kind of looks like some sort of high-tech medal of honour or something…