What do I need to build a drone? What's a good intro drone? How do I pick parts?
We've gotten these questions from so many people, so we decided to cover it in a blog post;
The reason this isn't covered often is because of how much goes into quad-copters and the learning curve involved, so let's go over the steps involved for picking your first Or second components.
There are a few things you will need to pilot your drone or drones.
First you need a controller/transmitter to talk to your drone and tell it what you want it to do. These don't come in many shapes or sizes and typically run on the 2.4Ghz spectrum. There are two major competitors; FrSky and Spektrum. Personally I stick to FrSky, it's a very popular choice as it is reliable and reasonably priced. The FrSky Taranis is easily the most popular radio in the drone community. Every transmitter will control in the same basic way, so do your research if you want to branch out.
Now assuming you're going to fly FPV (And why wouldn't you), you're going to need some goggles. This is the biggest hump to get over for many of us. You're going to have these basic choices; bi-screens or single screen, and large format or small format. Popularity sits with FatShark, which are bi-screen goggles (meaning they have a screen per eye). For various reasons some people prefer the single screen, if you have eye problems the bi-screens might be weird.
FatShark goggles are expensive, and the cheaper models screens are surprisingly small. This makes the Qaunum goggles an enticing option, for less than a couple hundred dollars you can get yourself a 7" screen and all the channels you'll need (I'll go over that in a minute). But for me these goggles make me sea sick. The best way to research is to try them on, which can obviously be difficult. I'd recommend looking for a local group and see if they'll let you try their goggles on. I understand it's frustrating.
Other options include Head Play and Sky Zone, from what I've read they are very good as well.
Now depending on what you choose for goggles, you may or may not need a receiver. FPV typically runs on the 5.8Ghz spectrum, and is very picky when it comes to running multiple transmitters in close proximity. We only Very recently broke the record in pilots flying at the same time; 16 quads in the air at a MultiGP race. So all that being said, diversity antenna receivers are currently the most efficient way to maintain a solid feed. For fat shark the original diversity is LaForge, made by UBAD. I'm not well versed in other brands because I fly FatShark Dominators, but there is a lot of information out there that I won't go over here.
Great! Now you can control your imaginary drone, And see where you're going! Ok this can get a bit complicated so let's get down to it.
Now is more decision time, are you going to go big or small? Fast or slow? Top notch or doable? Well my recommendation is to go with a 5" prop build that has plenty of power, I might get flamed for that but I have my reasons; yes it's going to be way too much for you to control, but you can have the software hold you back a bit. Other reasons include avoiding hitting the ground and not buying parts twice. But if you are not like me you may want to consider building a small-motor 5" or 4", I would say 3" but they are Very tiny and tough to build.
Now let's talk parts.
First you'll need a frame to put your parts on. There is Some controversy in frames, but what's most important is durability and build ease. Other variables include motor placement, weight distribution, and weight. Motor placement is how the motors are placed in space. For example the DroneHaus Mach5 is a perfect X, meaning an X where each line is 45 degrees from the other. Or if you made a square, the motors would be on the corners. Other motor placement includes H (a rectangle) and a "Stretched X" which is really just an H quad where the skinny side of the rectangle is front to back.
Now you'll want a power train, Motors and ESCs
Motors have many options, if you're going for slow, 1806 is slow for 5" and medium for 4". 1104 is slow for 4". And strangely enough 2205 is fast on both, props are weird.
KV plays a big role for your motor, it equates to RPM per volt. So if you have a 1KV motor and apply 2 volts the motor, it will spin at 2 Revolutions Per Minute. The most common KV is 2300, but there has been a lot of experimenting with "High KV" motors.
So if you want to buy a fast motor, stick to 2205 Stator size and 2300-2700 KV. If you want a torquey motor, get a 2206 2400-2600 KV motor. This is a recommendation for a powerful 5" quad, make sure you do your own research when building your first drone.
Now we need ESCs, this is a little easier to choose. For 90% of applications, 20 Amp ESCs have plenty of headroom for almost all quads, currently. There is an equation that tells you exactly how much you should need for motor and prop with what voltage, but 20 is still probably fine. Firmware becomes your number one enemy here, it has slowed down a little as of now, but having the newest firmware has meant needing new ESCs lately. There are a couple trains of thought that I go over in an earlier blog post Here.
There are a handful of popular choices, DYS XS20, Little Bee 20A-S, RotorGeeks 20+, and KISS 24. Team Black Sheep also recently released 25 Amp ESCs that look pretty cool!
Ok now we need our "Stack". This is what powers and stabilizes your quad. It typically consists of a PDB (Power Distribution Board), OSD (On Screen Display), and a FC (Flight Controller)
What the PDB does is takes the your battery input and sends it to all your ESCs and other components that need power. We Love using the RROSD, which is a PDB and OSD in one. You just wire all of your ESCs power to it, and your video system.
Now you need a Flight Controller. This is the brain of your quad, your input goes in, and magic motor control code comes out and makes your quad work! You can't really go Wrong choosing a flight controller, but you can certainly go Right. If that makes sense.
Most boards are defined by the processor they use; old boards used F1 chips, then as Naze32 became popular it was F2. Now many boards, like the RMRC DoDo, run F3 chips. I've found this to be more than enough, but we're now moving towards F4 chips. Personally I find that durability is more important, some boards I've used have burned their regulators or bricked. The DoDo has been a very reliable board in my experience, and I am quick to recommend it.
Ok now you need FPV. This is relatively easy to choose, you need a camera, video transmitter (VTX), and an antenna.
The absolute most common camera is the HS1177, it has been rebranded and packaged as many cameras but it generally costs about the same and produces a perfectly good picture for the purpose of piloting your drone.
Now you need a VTx to talk to those goggles we talked about so long ago. This is about as complicated as your FPV gets, you have to choose MW (which is how powerful your FPV signal is), and size/style. Usually 200Mw it's about as much as you should need, but if you want to get a little crazier go up to 4-600. Keep in mind that anything over 25 is illegal. So actually don't do any of that, really though don't do it. Don't.
Now you want it to be small enough to fit on your quad, and you probably want it to have a pigtail so you can mount your antenna somewhere remote-ish. In my book that narrows it down to the Hawkeye 200mw and the Team Black Sheep Unify Pro HV Adjustable Mumbo Jumbo. Both are awesome, the TBS unit is very small and can be adjusted from 25 to 400 (I think) it's a little more advanced than the hawkeye now, but both are good units and similarly priced.
Now you need an antenna! We're getting close. Ish.
Sure you can run the antenna that probably came with your transmitter, but don't. there are two main types of antennas that come into play for FPV; Dipole and Circular Polarized. Dipole is just a tuned piece of coax cable that radiates radio junk linearly. Circular Polarized usually consists of tuned "Lobes" that sort of wind up your signal, some magic happens and you have twice as much range and penetration. There are two styles, RHCP (Right Hand Circular Polarization) and LHCP. Most normal FPV folk run RHCP, it's been said to penetrate better and generally work better. But either is better than dipole.
All that being said, durability is the Number One attribute for an antenna. It's going to get smacked around and needs to be able to survive. We've like the Foxeer antennas quite a bit for this reason, but feel free to do your own testing.
Two things left!
You need a receiver that your transmitter/controller can talk to, that then talks to your Flight Controller. If you took my advice and got a Taranis then you'll need a XSR or X4R-SB (Get the depinned one ;)). If you didn't then you'll have to figure out what receiver you need and how it works, you'll basically be a linux user in a world of windows users. Nobody knows how you work.
Don't forget props! I'll have to do another blog post on choosing props, but typically your best bet without them is a good sling shot or maybe a friend with a strong arm.
Typically though I think it's safe to say 5045, tri-blade, and blunt nose will do you pretty well.
I hope that helps you get started! Please comment with any questions or concerns.