Is it necessary to use two RPIs?

Help / Getting Started
1

Hello.

Why do I need two RPIs, one to act as Air and the other one as Ground, when there are several Ground Control Software than can be used ?

How does one configure an RPI to be Air and not Ground ? What about vice-versa ?

2

Hi
The reason you need a Pi on Ground is because OpenHD can only run on Pi hardware, not x86 or such, at least at the moment.

AirPi becomes air when a camera is detected -or- the file „air.txt“ is present on the sd-Card root folder.

3

Can’t I connect a Ground Control software to the AirPi ?

I don’t need a camera.

What I really need is something to send and receive Telemetry Data in MavLink format to and from an Ardupilot Flight Controller.

4

Yes you can connect air to any groundcontrol software - through the groundpi - via Ethernet, wifi or usb.

If you don’t need a camera just create a file „air.txt“ I guess it should work as a telemetry-only System then.

But I also think a dedicated mavlink modem like „SiK radio“ is a better solution then ?

5

Since you obviously know more about these things than me, I would really like some help regarding my project. I have never worked with drones or drone software before getting this project and I have literally no idea what is what or what I’m doing.
I’ve been trying to get something to work for the past 3 months and I got nothing. 0.

I am supposed to make a drone capable of:

  • receiving commands regarding it’s flight(like “move left by x amount”, “land”, “ascend by x amount”);
  • sending telemetry data back to something that can act based on that data;
  • sending other types of data to a back-end server;
  • indoor flight using Marvelmind SuperBeacons as GPS.

Tech:

  • CubeOrange 00450025 30305114 35333339
    ChibiOS: d4fce84e
    ArduCopter V4.0.7 (0bb18a15)
  • Marvelmind Super Starter Set NIA-3D 868/915MHz which contains:
    1x Modem HW4.9 915
    5x Super Beacon 915-31.0-IMU

The project is divided into two parts:

But, I have encountered TONS of problems while trying to use an ESP32 with the CubeOrange. The biggest one is that each time the ESP is connected via RX and TX to the Flight Controller the ESP doesn’t work properly.

Then I moved to Raspberry, but things here are even more difficult, because, apparently I need two RPIs to make it work. And this ups the cost by quite a lot.

I don’t know anything about the video capabilities of the RPi. Are they any good ?
Why do all AirPis have camera ? What is it used for ? What kind of data does it send ? Can I use data coming from the camera ?

I have never heard of SiK radio before.
Can I use it to receive telemetry data and redirect that data to a server ?
Can I send flight commands to the drone with it ?

7

Oh wow that’s some high-end stuff you have there.

And yes the pi has pretty good video capabilities. We use it for live video and fly beyond line of sight. Like the birds :slight_smile:

The setup of your marvelmind set is described here, but I have zero experience with such things.

https://ardupilot.org/copter/docs/common-marvelmind.html?highlight=marvelmind

I suggest you forget about OpenHD and Dronebridge for now and exchange it for one of the following solutions to enable mavlink communication between your drone and groundstation (a Laptop ?). Both can do what you want. Send and and receive control and telemetry data.

Bluetooth: (Short range, but cheap and easy to use):
HC-05 Bluetooth module, around 5$, and your Laptop (?) probably has Bluetooth already.

HChttps://banggood.app.link/je2DtfZgThb

SiK radio: (long range, more expensive, 20-250$,
Needs 2 modules.

https://docs.px4.io/master/en/telemetry/rfd900_telemetry.html

8

Ah another solution (maybe nice for you as you want to fly indoors) regular WiFi !
You need a esp8266 for that. Costs maybe a dollar or two. 5-10$ for a premade module.

https://ardupilot.org/copter/docs/common-esp8266-telemetry.html