How To: Long Range FPV Quadcopter

Ever wanted to be able to fly around and admire the scenery from above? In this instructable, we are going to build a quadcopter that will allow you to do just that!

We will be using the TBS Discovery frame as it was designed with long range and FPV in mind and is therefore perfect for this application.

The quad will consist of the following components:

Parts

1x -FrSky D8R-II PLUS 2.4Ghz 8CH Receiver with Telemetery

1x -TBS Discovery Frame

2x -Upgraded Arms for DJI Flamewheel

4x -Quanum MT Series 2212 1000KV Brushless Multirotor Motor Built by DYS

4x -Afro ESC 30Amp Multi-rotor Motor Speed Controller (SimonK Firmware)

1x -Multistar High Capacity 4S 5200mAh Multi-Rotor Lipo Pack

1x -Naze32 Full flight controller with Baro and compass (MS5611)

1x -Ublox NEO-M8N Flight Controller GPS with Protective Shell

1x -Ultrasonic Module HC-SR04 Kingduino

1x -HobbyKing™ Lipo Voltage Checker (2S~8S)

1x -MultiStar Battery Strap 330mm

2x -HobbyKing™ Thin E-Prop Propeller 10x5 Black (CW) (2pcs)

2x -HobbyKing™ Thin E-Prop Propeller 10x5 Black (CCW) (2pcs)

1x -Nylon Standoff Kit

1x -Antenna Stand

First, we gather our parts and make sure that we have all the necessary parts and tools. For this build, we are going to need:

Tools

-A screwdriver kit with hex fittings

-A cordless drill (not required but helpful)

-Soldering iron and solder

-Pliers

-Wire cutters

-Wire strippers

-Blue thread lock (important that it is blue, not red or else you will never get this thing apart again)

-Double sided foam tape to stick things down

When completed, the frame should look like the image above. First, we solder the pin headers onto the board. It is important to do this first because it will be difficult to do once the frame is assembled. The aluminium standoffs go between the two fiberglass plates which also hold in the arms and hex screws hold the whole thing together. The screws should line up to their corresponding holes on the frame.

Assembly

Now, we will prepare the motors to be connected to the ESCs (Electric Speed Controller). Solder the bullet connectors onto the motors and place heat shrink over the newly installed connectors. Then, install the motors onto the arms of the quad by aligning them on the ends with the wires facing the main frame and screw the motors in using the included screws. Then, connect the wires the the ESCs and using zip ties, fasten them onto the arms of the frame. Do not worry about which wire goes where for now as we can reverse them later. After we are done, it should look like the image above.

Flashing

This part is unnecessary and the quad will fly just fine without doing this, but flashing the ESCs with BLHeli firmware will increase the responsiveness of the quad. Order an ESC programming tool such as this and plug it into a computer with "KKFlashTool" installed. A video on how to do this can be found here. After flashing, were ready to move onto the next step.

Disclaimer: This particular setup is suitable for a shorter range of flight, hence this section will be separated into two parts.

Regular Range

For distance under 3KM, a modded Turnigy 9X bound to a FrSky receiver should be sufficent. However, if you require more range, read on.

Long Range

For longer ranges, systems such as the DragonLink or the EZUHF RC system by Immersion RC are more suitable as they operate in the UHF (Ultra High Frequency) range. Some transmitters are even capable of up to 50KM of range but by that distance the quadcopter is likely to have run out of battery. The other benefit of using higher end systems is that they usually have failsafes which you can program to perform an instruction such as activating a switch or reducing the throttle when there is a loss of signal.

Bind the radio to the receiver using whatever method is for your particular model and stick the receiver with the antennas facing the back onto the top of the frame with the double sided foam tape. Then, use the antenna pedestal the stand the antenna wires up in a V-shape to prevent them from getting chopped off every time you fly the quad.

After the receiver is installed, we stick the GPS unit onto the top of the frame using double sided foam tape and the SONAR module onto the front of the bottom plate of the frame. We will deal with the wiring later.

Here comes the slightly complicated part. We will need to connect the ESCs, receiver, GPS, and SONAR to the flight controller. To make things easier, there is a labeled diagram of the wiring above. First, solder all of the pin headers that are supplied onto the controller board.

ESCs

Taking note of the arms, connect the ESC wires from each arm into pin headers 1-4 of the ESC section on the flight controller, with the front left arm being the first and the back left arm being the last.

Receiver

Using male to male servo extension leads, connect pins 1-8 of the receiver to the corresponding pins on the flight controller. If your receiver supports PPM (Pulse Position Modulation) mode, you only need to connect one wire onto pin 1 of the controller board.

GPS and SONAR

At this stage, we should have 1 pin header still free on the receiver section of the flight controller. Plug the 3 wires from the GPS unit into the empty port. The SONAR module will be plugged into the ESC section of the board.

After all of the electronics are connected, we can make the build look cleaner by using zip ties to secure the loose wires and to minimize the chances of a wire coming loose mid-flight from the vibrations.

Failsafes

Setting the failsafe on any model aircraft that will be flying any great distance is important as a loss of signal at this distance can damage property and even injure people. To set the failsafe on the Naze32 flight controller, go into the cleanflight software and click on the failsafe section. From there, you can set the flight controller up so that with GPS, if the receiver loses signal, the quadcopter will automatically return to it's home coordinates, or take off position. Once you have set the flight controller to do whatever you want in the case of the loss of signal, go to whichever model of receiver you have and set the failsafe there such that when there is no longer signal, it will activate one of the free auxiliary channels which will tell the flight controller to go into failsafe mode. This extra step may seem like a lot of work at first, but when you are flying kilometers away from yourself and you lose signal, you will be glad you had set it up.

Slide the battery into the back of the quadcopter and secure it with the battery strap. Loop the strap into the cutouts on the frame and over the battery.

The battery monitor/alarm can be stuck onto the receiver using double sided foam tape, making sure it can be reached by the balancing port of the battery.

The quadcopter wouldn't be able to fly without propellers, but unbalanced propellers create lots of vibrations which will affect video quality and stability of the flight controller so using a propeller balancing tool like shown above, we will find the side that the propeller tends to lean to and stick small pieces of tape on the opposing side to balance it out. I prefer sticking pieces of tape rather than sanding the propellers because sanding is permanent and if you make any mistakes, you have to sand the other side to balance it out.

Obviously, we want to be able to see what the drone sees, and for that we will need an FPV camera and goggles.

Connect the camera to the transmitter and solder the power cables onto the power points on the main board.

Mount the camera onto the frame using the included screws and zip tie the transmitter onto one of the arms and bend the antenna upright.

Disclaimer: I do not have an FPV system currently installed, the images above are from their respective product pages.

Check all of the connections and make sure everything is plugged in correctly. Before plugging in the battery REMOVE ALL THE PROPELLERS in case something goes wrong and the motors go full throttle immediately. I cannot stress how important this is and failure to do so may result in serious injury (I speak from experience, it's not fun).

Now go to your computer and install CleanFlight from the Web Store on Google Chrome. Plug the Naze32 into the computer and setup the board. Since there are too many steps to put into an instructable, detailed video series on how to setup the board can be found here.

Now we have to adjust the PID values of the flight controller to get the quadcopter to respond the way we want it to. P stand for proportional, I for integral, and D for derivative. Here are videos made by other great youtubers to demonstrate how to tune the flight controller.

Thanks for reading and if you enjoyed this instructable, please do vote for it in the Drones contest. This quadcopter has been fun to build and test.

If you have any questions or suggestions, leave them in the comments below.

Thanks!