We have designed a boat which is over 4 meters long and can have a weight of 350 kg. I have a GNSS (http://navsys.no/produkter/gnssgps/altus-nr3), is it possible to connect this to the autopilot somehow? Perhaps through a laptop onboard the boat?
If you use Pixhawk you can connect the NR3 to gps1 input.
Output NMEA GGA, RMC and VTG on Serial port (use lemo 9 pins connector on your GNSS) connect rx, tx and gnd on ttl converter (sparkfun for me), output the converter to gps1 connector ( connect rx, tx, gnd, +3.3V).
You can read this post NMEA position input to pixhawk
Thank you so much Ludovic!