Hi, I'm considering jumping into ardupilot, so far I'm undecided on APM or Pixhawk. I have a grand plan that I would like some feedback on:
Rather than use a separate 2 way radio link with its own antenna etc, I'd like to use an existing FrSky receiver and Taranis transmitter. Note that my aim for this would be for both telemetry AND waypoint setting etc. The aim would be to get telemetry showing on both the Taranis and the mission planner, and waypoint setting via laptop. with most of the telemetry coming from the autopilot.
As far as I know, both telemetry and control are done using MAVLink via UART for both APM and Pixhawk. Is that correct? FrSky make a SP2UART converter that seems to give you a 2 way UART over the Smart Port bus. My plan would therefore be to use a SP2UART on each end, and an Arduino to convert the MAVLink telemetry to Smart Port. Depending on the data rate I might be able to leave the MAVLink packets in, but otherwise I would convert the relevant ones to Smart Port on the aircraft (there is already a project for this) and then convert them back again on the ground.
Laptop---Teensy---SP2UART---Taranis~~~~~~~~~~~~X6R---SP2UART---Arduino---APM
Or if sufficient data rate:
Laptop---FTDI---SP2UART---Taranis~~~~~~~~~~~~X6R---SP2UART---Teensy---APM
So my question is: what are all the reasons why I am insane and this won't this work? Mainly from an APM/Pixhawk perspective - I will probably post this on the opentx forum to get the Taranis side.
Replies
Hi Andy,
1 - Comment
FYI : this project (link 1) already convert MAVlink to S.Port from such that
Taranis~~~~~~~~~~~~X6R---teensy---APM.
It is not two ways, it doesn't convert the data from the taranis to mission planner. That is why I would love to use your project : I am running the taranis telemetry in parallel with the 3DR radio telemetry. Clearly redundant by lack of a technical solution.
2 - Question
Where can I find a simple arduino sketch that feeds the FrSky S.Port with my own telemetry data ? I already have an arduino sketch (link 2) that computes the RPM value as an int, and I would like to send it to the taranis by hooking my arduino board to the X8R.
Can someone point me to similar projects ? I have hard time to deciper the long and tricky piece of code of the MavLink to FrSky X8R S.Port converter (link1 cited above). A simpler project (easier and shorter code) would help me a lot.
The APM is old technology. The poor amtel has run out of memory and features are being removed to make way for new stuff. Currently its most functionality from the CLI (terminal), which is perhaps annoying but one can still use the Mission Planner UI to do those same things. Other real features (the Kalman filter stuff) are only available on the Pixhawk, and thats really important because it makes the flight stability and experience that much better.
Unfortunately the APM will slowly fade and the extra found on Pixhawk will continue to grow. Its a bit like buying a C64 when the Amiga has come out.
Sure, I get that, and may well get a Pixhawk. I'm not sure it actually affects my project overall though does it? i.e. if it works it will work for both, and if it doesn't work for one it won't work for the other either :) At least that's my understanding.
(SBus vs CPPM aside I mean).