The latest ArduPilot Fail Safe firmware V1.6 includes a state of the art system to detected if we have glitches or bad signal, triggering the RTL and avoiding undesired "Remote Resets".How it works?Well, the first part is just a low pass filter that works only when switching to autopilot, this prevent undesired toggles to autopilot mode when the signals becomes "noisy" and also avoiding undesired resets (the system mistakenly thinks you are toggling the switch).The second parts is a "Valid Pulse Width Checker", this is a very simple code that will increment a counter every good pulse received, if the system receive 75 valid frames (by default) it will thrust the commands we send through the remote control, otherwise will trigger RTL, and reinforces the prevention of undesired "Remote Resets" caused by noise.Of course the latest code could be found in the same place as always, here.The Attiny has been tested only on ground with my 72mhz Futaba and two different receivers, after confirmation i will remove the beta tag, and i will try convince Nathan to flash it on the SparkFun boards, in the meantime you can try it with your AVR programmer. ;-)Whats next?Well right now I'm working on the new ArduPilot firmware code name "Hybrid", will support NMEA, SIRF , uBlox UBX and VENUS 10HZ GPS protocols, on the same code, and you can switch between them by just changing a single variable, bad news, only works on 328. =P
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  • can we set a 6 positioned switch?

  • Ok, interesting question here.....

    I was thinking of using the new code...however.....

    the project we are working on requires something a little different.....

    Before i go to far in, rules and regs not withstanding here......

    Part of the project is to allow the aircraft to fly from point to point, in this case take off here ..climb to 1000` set a course to point 'B' Via a good number of waypoints,

    now...i know about all the rules and regs here in the UK Cap762/Cap658 this deos not apply, (i will let you guys work out the reason for yourselves)

    obviously in testing the UAV is followed by a car to make sure were not buggering of to south africa or anything, my concern is that we get half way through the mission and get a dead spot, and the UAV gets all confoooooosed and decides to go home..?

    We have 40mile V radio link, 20mile data link, the osd is updated with the same waypoints as the AP (same GPS is being used)

    the Point to Point is 6Miles.....

    Any thoughts?



  • Can anyone tell me if this AVR programmer would work for flashing the Atiny on ArduPilot to Firmware V1.6?
  • Thanks Jordi, I'll test your suggestion.
  • Developer

    JR = Spektrum, The JR has the same problem as Spektrum (Is the same company i guess). Because is 100000x more secure than any Multiplex, Futaba radio, even if you switch off the radio the JR receiver will still pulsing the servos in neutral mode so the Fail Safe detector will never kick in. Maybe it has the option for signal lost like Spektrum to define the fail mode servo position and you can set it to switch the RTL mode.
  • anyone from europe? maybe...
  • 3D Robotics
    I'm afraid every Rx is different and you'll have to experiment with one that works for you. We're in the US and aren't able to test 35mhz gear.
  • Yes, just the signal lost function doesn't work ... but the code work well for three position switch. Is there any change for the code?
  • 3D Robotics
    It doesn't work at all, or it's just the signal loss function that doesn't work?
  • Have anyone successes using this v1.6 code with 35mhz radio? It don't work for me :( I'm using JR 9xII 35mhz.
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