Autopilot and Drone Choice

multirotor

#1

Hello,

As part of my University course, I am creating a drone which will hopefully be intelligent (target is search and rescue).

I am looking for a drone that, in essence, I can program (eg in Python). As these don’t really seem available, a work around is to have a drone carry a Raspberry Pi, with a few peripherals eg a Pi Cam and a microphone attached. This will be fairly light, around 100g, although if a separate power source is needed (likely) this will add another 100g.

I have looked at the Pixhawk + ArduCopter 3DR 850KV. These seem most suitable.

So, my main 3 questions are:

  1. Will the ArduCopter easily be able to handle the load, and be easy enough to attach a small box to?
  2. How can I connect a Pi to the Arducopter to control it, say via a Python API (ArduPilot)? A wired connection would be best, but I could do via wireless/some telemetry connection.
  3. What is the best way to get a lot of data to the ground? Short range is not an issue. I have used radio telemetry before, and the data rate was too low for what I want.

Any other suggestions/thoughts would be greatly appreciated,

Jake


#2

1 - with the 850Kv motors and 10 inch props the motors will be able to produce about 2.8Kg thrust. Given that you want to hover at about 50% thrust the total weight of your arducopter should not weight much more than 1.6Kg. I cant recall of hand what the weight of the quad frame is , but in general if you just need to add another 100g then the basic setup will be fine :-). To learn more check out our guide on what motor you need for your drone.

Here are the motor test data table for the arducopter 850Kv motors should you be interested:

2 - This is slightly more tricky, but the best way would be to simply talk between the two via MAVlink protocol which has python bindings if you want to work in python. There is actualy a great guide on how to connect your ardupilot/arducopter to a raspberry pi here

3 - My suggestion would be to use a high power wifi router on the raspberry pi. Most of the off the shelf versions only work to about 100m, but there are some other ones available that should go further but it depends on how much you want to spend, and how much weight you have. What sort of range would you need?


#3

Thanks for the reply, and sorry for the delay - I was away.

Especially useful is the link to the MAVlink tutorial; it is perfect for me!

For the wifi router, do you mean a land-based router to connect to a USB wifi dongle on the Pi, or something more complex that is based on the Pi? If the first then that is fine. I was wondering if there was a better (unknown) alternative to wifi, but if it’s the best solution then it’s easy.

Cost isn’t too much of an issue; it’s in conjunction with a company and is more proof of concept. They want more range, they can pay more etc.

Thanks again!


#4

You can get some USB wifi adapters with high gain antennas to increase the range, and when coupled to a high gain ground unit you should get more range. That should be good enough for initial development and it should not cost too much.

If you are looking for a high speed, long range network link you can look at something from ubiquity networks Bullet M5. Its only 180g and only around $80 and claims wifi range up to 20Km. However not sure about latency issues.