Friday, September 18, 2015

Getting Ready to Build Your Own Quadcopter (2016 Update)

With over a year of successful Build Your Own Quadcopterclasses behind us now, the third class of 2015 is up on the calendar on the weekend of October 17-18.
As mentioned in the class description, there are a few things participants will need to bring with them to the class.
A question that is frequently asked is why some of the required equipment is not included in the price of the class. The primary reason is that some people may already have their own equipment.
My goal here is to ensure that you bring the correct equipment to the class so that you can leave with a fully configured, flying quadcopter.
Here are the things you’ll need to bring:
  • A programmable RC radio transmitter, capable of at least 6 channels, channel reversing and adjustable channel endpoints.
  • An RC radio receiver, capable of at least 6 channels
  • A LiPo battery pack, 3-4S (3-4 cells in series,) in the 2000 – 4000 mAh range
  • A LiPo battery pack charger
  • A laptop or portable computer with working wi-fi or wired ethernet port, at least one working USBport and with Google Chrome installed and working. Windows 7 or 8, Mac OSX or any of the popular Linux distributions should work. Chromebooks will not work as there is no way to install the required USB driver.
If you already have some electronics/hobby tools of your own, feel free to bring them. We provide tools for the class but there are never enough tools for everyone to use at once so bringing your own can help streamline the class flow. Here are some of the things we’ll be using:
  • Soldering iron – 60 Watts or better.
  • Helping hands – or some other way to hold wires and parts together while soldering.
  • Wire cutters
  • Wire strippers
  • Jeweler’s screwdrivers
  • 1.5, 2.0 and 2.5mm hex drivers
  • Hobby knife (X-Acto knife)
  • Micro USB cable
Let’s delve a bit deeper into the RC Transmitter. Here are the key features you’re looking for:
  • Mode 2 (vs. Mode 1). This will be explained in detail in the class, but it determines which functions each stick controls. Unless you’re already accustomed to flying RC models with a Mode 1 transmitter, you’ll want Mode 2. Most radios are convertible between Mode 1 and Mode 2, but it’s easier to just get a Mode 2 to begin with.
  • At least 6 channels. This is a must-have. If you get into flying multicopters, you’ll want all the channels you can get.
  • Channel reversing – The ability to reverse the output of any channel. This is a must-have feature. If your radio doesn’t have this, it probably won’t work for the class.
  • Adjustable channel endpoints – the ability to determine what the minimum and maximum output values are for each channel. This is a must-have feature. If your radio doesn’t have this, it probably won’t work for the class.
  • Rates and Expo (exponential interpolation) – The ability to adjust the sensitivity of the controls. Not a requirement, but very helpful for novice and advanced pilots alike.
  • Multiple model memory – The ability to store all of your programming options for more than one aircraft. Most transmitters that meet the other requirements will have this feature as well.
The RC receiver is a bit simpler to choose:
  • Compatible with your transmitter – It needs to be able to bind to (talk to) your transmitter. If you’re unsure, most manufacturers sell combo packs with the transmitter and receiver together.
  • At least 6 channels – Again, more would be better.
The LiPo battery pack is also a fairly simple choice. You’re looking for a 3-4 (3-4 cells wired in series) lithium polymer (LiPo) battery pack in the capacity range of 2000-4000 mAh (milliampere-hours) or 2-4 amp-hours. The higher the capacity, the longer flight time you will get. Don’t worry about which connector is on the end of the battery – it’s easy to replace in class. XT60 connectors are supplied in the class. If you already have batteries with a different kind of connector, then bring some spare matching connectors with you and you can wire up your quadcopter to match your existing batteries.
The LiPo charger is an important piece of equipment that should not be overlooked. LiPo batteries require a special kind of charger that balances all of the cells as it charges them. There are many choices available ranging from $20 to over $500. The main difference is that the better chargers can charge faster, have more charging options and tend to treat your batteries a bit more kindly, thus extending their life. Be mindful that some chargers only take DC power for input, and will require an external power supply.
If you’re new to RC flying or you are unsure about what equipment to get, I’ve put together some equipment choices below that will work well for the class.
RC Transmitter/Receiver:
  • FrSky X9D or X9D Plus (Taranis.) FrSky (pronounced Free Sky) is a relative newcomer to the RC transmitter market and started selling the X9D about two years ago. I’ve owned an X9D for over a year now and highly recommend it. It’s a 16-channel transmitter with tons of features, fully configurable switches and is the easiest-to-program transmitter I’ve ever used. You can typically find a combo with the X9D and the X8R 8-channel receiver for around $230. Because of their popularity, they can be a bit hard to find in stock. As of 9/15, GetFPV, HobbyKing and Ready Made RC have the X9D Plus combo in stock (direct links below.) I've now had several prior students tell me they wished they would have just gotten the Taranis rather than the 9XR Pro or 9XR after seeing its functionality and ease of use.
  • Turnigy 9XR Pro. Turnigy is HobbyKing’s “store brand.” These units come without a radio module, so you’ll need to pick up a radio module and receiver combo pack as well. It’s a 9-channel transmitter with lots of functionality for the price. The transmitter comes without a battery pack. Here are the items you’ll need if you want to go this route:
  • Turnigy 9XR. The predecessor to the 9XR Pro, it has a slightly different physical layout and an earlier-generation processor and firmware. Like the 9XR Pro, it’s also a 9-channel transmitter and comes without the radio module, so again you’ll need a radio module and receiver combo. You’ll need a battery for this as well. Here are the items you’ll need if you want to go this route:
  • Tactic TTR850. Tactic, a sub-brand of Hobbico (who has been around for many years,) has recently started making affordable RC transmitters. The TTR850 is an 8-channel, fully programmable transmitter with comfortable ergonomics, lots of features and is fairly easy to use. You can get a combo includes the transmitter and an 8-channel receiver for a little over $200.
  • Tactic TTX650. The little brother to the TTX850, it’s a 6-channel variant with similar ergonomics and feature set. You can get a combo that includes the transmitter and a 6-channel receiver for around $150.
LiPo Charger:
LiPo Battery Pack:
Some tips on ordering from HobbyKing:
  • Be mindful of the warehouse. HobbyKing has multiple warehouses from which they ship. Always try to order from one of the US warehouses. You cannot combine items from different warehouses on the same order.
  • Never order batteries from the international warehouse. The hazmat charges from China make it not worth your while and you incur extra delays due to customs and inspections.
  • Order now if it’s in stock. HobbyKing’s stock is volatile. If you see something you want today, order it today. It may be gone tomorrow and not be in stock again for a month or two.
  • Expect delays. Especially if you order from the international warehouse – I’ve had orders take 1.5 months to arrive.