Hi all,OK this is really just a information post really,Checking your failsafes...Had a horrid moment at teh weekend..After losing an aircraft the other week, i replaced all my gear for the the second UAV....(so as not to risk the biggun')Sorted it all, prgrammed it all...The uBlox final showed from our fearless leaders...all excited got it all sorted, tested on the bench.....decided to commit to aviation.Loaded her all up went out to the runway.....well, the fun starts..Ublox truly is the puppies dangly bits, aircraft tracked straight to all WP`s, no mucking about....she was on song....Flew the course 6Wps 11 times, SPOT ON!!!!Now for the crunch...Myself and all my pilots use the ASSAN 2.4ghz system (been using it long before it was NOT classed as a grey import due to its superb range and NOTHING can knock it out of the air (dont tell anyone, but had UAV at 4.5miles it!...shhhhhhhh)So in the lost 2nd UAV, i was using V1 Rx's, if you switch off the Tx it defaults and stays in WP mode....Well 'Total DONKEY' here decided that when fitting out the latest aircraft i could only get V2 versions...assuming they had the same software did the above flight !!! NEVER ASSUME ANYTHING!!!Standing there having a smoke feeling totally smug and sefl satisfied that it was playing ball, i decided to switch off the TX, well....V2 ASSAN Rx`s DONT have the sme software..the sod shut down!!!! Turned everything off! wnet intot a near vertical dive, obviously i switched on, in a panic, but left the switch in WP mode.....welll she went in hard really hard...So hard teh cells smashed thier way through the RX, the AP tried to do the same, knocking teh preasure sensor off teh shield, destroying teh molex GPS connector, and generally making a complete mess of everything.After re-soldering all the bits back onto teh shield, and drilling and glueing a new tube onto the preasure sensor, it all worked again, god only knows how, the shield and the preasure sensor is a funny old shape!!!!The new uBlox, is smashed bad....strangly this was packed in the rear fuselage, away from anythig hard...It turns out that the GPS is ok except teh aerial is smashed off, CAN YOU BUY THESE?Moral of this story, NEVER EVER take anything for granted, check everything twice at least, on teh ground...Chris/Jordi, Well done on a superb AP, was working a treat.....and if anyone can tell me where to buy a new aerial for the GPS that would be great, dont fancy shelling another $90 for new uBlox GPS...

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  • Dr. Mike,
    I think you said you plane kept flying for 10 mins. with the Tx off, I assume like waypoint mode?
    The Aurdupilot failsafe goes to RTL upon loss of ch 6 ppm. It doesn't know what the reciever is recieving, only what it's putting out. The failsafe on your reciever keeps pulsing away while the Tx is off. You must set the reciever's channel 6 failsafe to to what ever RTL is.
  • HI Guys,

    Morli, thanks for the information, will def look into that if yougn Gary V cant help.

    Gary V, you realise i live in the UK? happy to Paypal postage to you, would be a worthy end to a wonderfull GPS if you are still willing to help, B***Y annoyed about that...lol....the one part i thought was safe! Thanks in advance.....

    Gary M, you got that right!....omelettes....just wish i could stop loosing or destroying aircraft!..LOL...to ba fair, we have bee nvery lucky, both screw ups were due to not applying the 6P`s when you do anything.....

    Morli, I personally have not used the millswood, however, as yo usay they need a heart beat, a pulse if you will, but my Rx shut completely down....

    Now i wouldnt have believed this but when i ran teh system up on the bench (after re-solding all the board back together), it simply shut down!, tried it againwith a V1 Rx, it works fine...re-tried another V2 Rx, same thing very odd, and for the life of me i cant see why they would change the software...with V1 if you lose Tx it simply levels all the servos and closes the throttle, fully understanble....but the V2`s very odd, when i tried teh V2 in a standard application, it closes the throttle, but continues to function, but with ch5 as your controller for the AP, is acts like it shuts down....further investigation required...


    Put all the gear into yet another airframe....everything works a treat, back the trusty old EM406, bit wandery on navigation, but again flew all WP`s many times, in a right whoolly also, 20-30mph winds (UK is getting battered from severe weather) and So was i , freezing and wet by the time we finished....but very smug!....also tested Fate again, put the old Tx off, and on the floor....watched the old girl fly for about 10 mins with no Tx, again a little odd as i thought that the new boards have RTL with no TX, but no complaints...

    1 Complete airframe
    1 working AP
    1 cold but happy and smug Mike!!!!

    No omelettes this time or eggs to make it!..
  • Moderator
    I think Andrew was making his failsafe work with Ardupilot as well, http://www.millswoodeng.com.au/failsafe_device.html bad luck with the off, its that omelette thing isn't it ;-)
  • Developer
    Sorry to hear this, your UAV must have hit very hard.. good luck fixing uBlox & keep your chin up !!
  • I have an old u-blox module with I fried with a good antenna on it. If you would e-mail me a ship to address I would be glad to stick a postage stamp and label on it, send it n/c and wish you good luck on recovering some good parts off of it. It will be a few days before I get home where it is. I am out of town working but it could be in the mail to you Friday if all goes good here and I can get home on time. Hopefully the mail runs friday "dont know what the holiday will do to the mail service". My e-mail address is whitebirdlodge@yahoo.com

    good luck (been there done that)
  • Admin
    hi Dr.Mike ,
    Very Sorry to hear about the Failsafe failure...eeee, Hope u get all the electronics fixed soon. The antenna in Ublox( assuming you have this model) is smart antenna called Sarantel geohelix and info is here
    This site shows where to buy but am not sure if you can buy one pc :( , good luck


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