During the Maker Faire event I demonstrated my own drone based on Netduino. And I got lots of questions about hardware but not quite as many about software. Several people even told me that they tried to assemble own drone but failed. That’s why I decided to show my experience there. I am going to have vacation this week, so, I put aside software development and new APIs for some time and have some fun trying to assemble a new drone.
I am going to develop a powerful outdoor drone. So, it should be heavy enough to fly stable despite the wind and at the same time it should have enough power to fly up as well.
Let’s start with components which you need to buy.
Pay attention that in some cases it requires some time to receive it by mail. Usually I use robotshop.ca – if they have something you can get it in 2-3 days but it’s a little bit expensive compared to amazon and they only have a few components in each category. If I am ready to wait some time I use amazon.ca or amazon.com – the second one has many more components and 2-3 days delivery option for some of them but you will need visit the US to get your package.
First of all you need to decide which type of drone you are going to build and select the right frame. I would recommend to start with a quadcopter but during my vacation I will build a hexacopter. It’s better to select a metal (aluminum) frame because it’s not easy to break this frame. Of course, you can build your own frame using wood or metal parts but you spend much more time and lots of money compared to exiting frames which starts from $17. I have tested two frames: X525 and 650X6. They are pretty good and not very expensive.
Once you know number of motors based on your frame you can select motors. For drone, you need to buy brushless motors which can run you propellers with different speeds. Additionally you need to buy a special control board for each motor called ESC. Thanks to ESC you can run your motors with different speed and motors have as much energy as needed. Different brushless motors require different ESC (based on voltage), so you need to read specification for motors before to buy ESCs. For the frames which I mentioned early I would recommend to buy 1000KV motors like A2212. You even can find pack of similar motors with ESC and propellers. I like this pack and usually I buy it.
Motors and ESCs is the most expensive part of the drone but the second one is battery pack. If you want to fly 20-30 minutes you need to buy a good LiPo battery and you need to buy a charger as well. I bought a 5100 mAh battery but you can buy anything from 2200 mAh. Just verify that it produces 11.1 Volts of power – it guarantees that you will have enough power for your motors and control board. Charger is usually expensive as well but you need a way to power your battery.
In order to operate your drone you need to buy radio control receiver and transmitter. I have FlySky RC but you can buy anything. In general you can fly using 4 channels only but you can use other channels for camera or something like this. Pay special attention that from time to time you can find some receivers which don’t work with common transmitters. So it’s better to buy both things together from the same company. Of course, you can use WiFi modules to operate drones from your phone or laptop but in this case your drone will not fly far away.
The most important part of your drone is the control board which sends signals to your motors, receives signal from your RC and implements some algorithms for stabilizing your drone. Usually this board contains several sensors like accelerometer and gyroscope but you can add barometer and GPS as well. For the first drone it’s enough to have just Accelerometer and gyro. I would recommend OpenPilot board because that software supports wizard which helps setup your drone, and drones based on OpenPilot are very stable. I used MultiWii boards as well but you need spend much time in order to setup those boards, and I encountered some problems with algorithms there. You can use Arduino, Netduino and even Raspberry and implement your own algorithms but it requires additional time and good math knowledge.
Finally, you need to buy some components which help to solder the frame like soldering iron, iron wires, connectors, power distribution board. Once you have all these things you are ready to start assembling your drone.
Next time I will show how to assemble my hexacopter step by step but at the end of the post I want to share list of expenses for my drone:
- Frame – $38
- Brushless motors (two packs, because I need at least 6 motors) – $146
- Power distribution board – $7
- Wires – $10
- Shrink Tubes – $3
- Banana connectors – $5
- Connectors – $8
- Battery – $38
- Charging station - $23 (probably, it’s better to buy more expensive charger in order to avoid big boom at your house)
- RC – $100
- Flight control board – $19
- Soldering iron and some stuff there – $30
So, total price of my drone is about $427 but there are still opportunities to cut down the price. For example you can buy cheaper RC, battery etc. At the same time you can increase the price adding camera, GPS, barometer etc.