Talking to Navio2 + RP3A+ via Wifi

Hi Everyone! While waiting for my NAVIO2 to be delivered :partying_face::partying_face: I still have to clarify a topic I’ve been searching around but I’m not sure about: how to exchange data with the drone

My goal is to build up a drone (Navio2+RP3A+) and control it only via my mac: basically I would like to send instructions “fly to that point or a set of points” in real time from my mac and retrieve periodically all the telemetry data (battery voltage level, GPS satellites, temp, etc) to make sure everything is ok. I’m not interested in video streaming on a first step …

Is that something I can do by using the Wifi module of the RP3A+ or is it necessary to buy an additional telemetry module?

By using Wifi, what is the range I could possibly reach and is there a way to improve it? I need to send and receive only simple data (for example the next point where I want to navigate or the Return to Home Signal and be updated about the current drone coordinates). Maybe a special router on the ground could help to boost the signal?

Hi Emanuel,

how to exchange data with the drone

You can connect Navio2 to GCS (Mission Planner, QGC) on your laptop or phone to get all the required information about your drone in real-time.

Is that something I can do by using the Wifi module of the RP3A+ or is it necessary to buy an additional telemetry module?

The range of built-in Wi-Fi module on the RPi isn’t suitable for drone telemetry. It’s better to use an additional module for this purpose (Wi-Fi or radio).

By using Wifi, what is the range I could possibly reach and is there a way to improve it?

Range mostly depends on the specifications of telemetry modules and can vary from a few meters to several kilometers. I’m afraid we can’t recommend any specific model, usually, users choose them depending on the project requirements.

Hi, thanks for your feedback! I’m back on this topic now that I’m ready to fly on the field…
What about the wifi module ESP8266? I’ve been looking around and, I found no information about compatibility with the Navio2. Anybody had experience with it?

The ESP8266 is meant for Flightcontrollers without the ability to connect USB wifi. With a RPi you can connect any USB wifi dongle you want, so an ESP8266 does not really make sense.

Thanks Sebastian for your feedback! The reason behind is that it is a very compact unit … I need to save space and weight on my drone and this ESP8266 is really tiny. Do you have anything to suggest that is very lightweight, that works over usb or uart?

The problem with any radio equipment is antenna placement.
The internal wifi of the RPi is severly handicapped, because it is sandwiched between two PCBs.
Any solution you might choose, should be placed away from other electronics. I would choose the smallest USB wifi adapter with an external antenna or a “nano” adapter and a thin usb extension cable. Wifi will never give you great range. There are many factors that influence the result. Other wifis, weather (humidity, fog, rain), obstacles in the fresnel zone, antenna placement, relative antenna orientation, etc.
My ground rover has an alfa ac (set to 802.11n, 2.4GHz) wifi adapter, antennas ca. 50cm from the ground. The remote also has an alfa wifi adapter and two directional antennas. With this setup, I get 200m to 250m range with buildings and other wifi around, before video gets to choppy to go on. RC and telemetry usually work a little bit longer (it is all going through the same wifi link), but at 200m it is really hard to see the rovers orientation.

Thanks for all the info, Sebastian. I will search for some solutions, based on your suggestions. In my application, I don’t need any video streaming trough the WiFi. I only need to keep the telemetry link open when the drone is flying autonomously … With the ESP8266, on a Youtube video, some guys arrived to about 400 meters with pure device (and horizontally through many obstacles) and up to some kilometer by using a dish ( https://www.youtube.com/watch?v=7BYdZ_24yg0&t=197s ).
For me reaching 500 meters of clear telemetry streaming would be really great !