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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  • Jordi, I tried your 1.6 with my AT 168 and AT328 brds. Did not work. I had to go back to 1.5. I noticed the Arduino is always in the manual mode, I can never select RTL or waypoints unless I use 1.5. Any suggestions?
  • Andrew: that's perfect idea that should work!
    I already know that Spektrum transmitter is by default configured to have throttle lever at bottom producing signal at ~10% of PWM range (1000ms ... 2000ms), and ESC treats it as no juice for motor. So doing transmitter/receiver binding with extra trim of throttle at ~0% should make it possible to distinguish RC failsafe mode. No more hacks with monitoring other channels.
    Thanks for tip.
  • I suggested this on the rcgroups forums, but one option for the 2.4ghz people with only a throttle failsafe is to program the throttle failsafe to the lowest possible setting. For normal flight, you would start your esc with the throttle trim a little higher than the lowest possible setting. In normal flight, the throttle will only go down to the trim setting end point. However, if the plane goes out of range, the throttle end point would activate. All we would have to do is get the ardupilot to RTL when throttle is at this lowest failsafe set point.
  • 3D Robotics
    Neal, all this is on the product's home page--the code defaults to RTL. Please do a little more reading here before asking more questions--the community is best served if we use our time to develop new products here and improve the ones we've got, as well as to be responsive to real tech support issues. But if you have a problem that is not already answered on the site, we would be glad to deal with it.
  • ok.. then with that said.. does the ardu board from spark fun have the ability of RTL and if so.. how do i enable it..?
  • 3D Robotics
    Also, the way you get the firmware is to download it from the link in the post. You need an AVR programmer like the AVRISP II to burn it on the chip.
  • Developer

    No board coming from Sparkfun have this version already, in other words, no, you don't have the firmware. Only exists two firmware versions, the one is in your board and the one mentioned in this post.
  • I purchase the ardu pilot board about 1 month ago.. do i have the firmware update.. if not how can i get it.. and how can i tell what current firmware I am running...
  • Developer
    I only tested with 72 mhz futaba radio, and works, 2.4ghz all are different, but at least spektrum has some receivers with this options, and this firmware don't affect or benefit 2.4ghz spektrums...
  • but this is just usefull for those without failsafe in the rx right?
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