How to make a quad copter
- This paper is trying to cover the construction of a quad-copter starting from 0 knowledge about it.
- This paper covers step by step instructions for ardu-copter build using eBay purchased parts.
- Requires minimal knowledge of soldering and electrical.
1.0 BackgroundAny copter major components are:
- Remote Transmitter and Receiver,
- Model/Flight Controller
- Electronic Speed Control (ESC) for motors.
On the TX, usually each knob or switch is associated to a separate channel. The TX's, is sending commands over these channels to RX. On the RX there are several output pins, usually one per channel. The RX is connected with the flight controller over several channels. The logic between user intend and copter
sensors is performed in the controller. The result of signal processing ( user intend + sensor-data -> outputs) is delivered to the output pins. For a quad copter we will use 4 outputs. For a hexcopter we would use 6 pins, and for a octocopter, all eight outputs. The output signal is amplified then by motors voltage/current amplifiers. They are called ESC. ESC stands for Electronic Speed Controller. The last generation ESC are smart modules which run firmware software as well. They processes the output from the controller and provide to the motors right waveform for spinning them up. The ESC can be programmed by a precise sequences of input levels (up/downs) to target a wide range of batteries and motors. The servos or motors are the final components of the craft. They transform the electric energy to mechanical energy.
Remote ControlAlmost any remote with at least 6 channels (can send 6 different commands at the same time) designed for RC model working in PWM (Pulse wave modulation). The remote is shipped usually with it's receiver (RX) module. To take advantage of al ardu-copter features the remote should have at least 6 channels. What are channels. The channels are like on the TV, independent transport pipes over the 2.4-2.5 Ghz. The Transmitter knobs (TX) can be assigned to any channel pragmatically from the TX menu set up options. Each decent TX transmitter has this kind of Set-up. This time we choose Turnigy 9X, 9 channels remote. which is s decent remote.
eBay search: Turnigy 9X, 9
Flight ControllerAPM 2.6 Flight controller. FC is a micro computer. It has additional sensors for: atmospheric pressure to sense the altitude, accelerometer, to sense the acceleration and position, compass to senses the direction relative to earth and GPS. Some sensors are soldered on the same board with the microprocessor and some are external. The APM we buy has external compass and GPS. The other sensors are on-board. Compass and GPS usually are mounted on a separate
module (GPS+COPMPAS) same board and they are connected to the Flight Controller by I2C data bus. I2C data bus is a 2 wire serial protocol where multiple peripherals share same physical wires. For a basic stabilisation simple mode, the flight controller takes inputs from RX-remote and accelerometer. It
process the User Input + the internal accelerometer (keeping the quad horizontally) and applies a set of rules using PID's on each axis to full fill and act towards intended target. For other flight modes as we would see MAP, GPS and or COMPASS should work flawless.
eBay search: APM 2.6 (If is chinesse never flash it with versions after 2.6)
Motors and ESC,Any suitable for the current and size of the copter. The motors are Step by Step electric motors with 3 phases and multiple pools (usually 12). The motors for high velocity spins are brush-less. ESC stands for Electronic Speed controller. All modern ESC contains microchips and can be programmed to target different types of motors, different type of loads, start stop, currents and so on. The ESC takes PWM (pulse variable modulation wave form) from Flight controller, pre-process it for the motor it was programmed , amplify it's to the current and motor voltage levels and apply it to the 3 phase motors.
Prerequisites & Tools
- Soldering station or solder pen.
- Soldering solder and rosin
- Screw driver with various set of heads and pliers.
- Exterior double sided tape (Home Depot)
- 5V, over 500mA stabilised power supply.
- Digital/Analogue Multimeter.
- Aluminium Tape
- Cigarette lighter
- Heat shrink tubing of different diameters
Note: Some eBay sellers might be outdated. ()
- ArduPilot Mega APM2.6 + NEO 7N High Quality GPS..Fisherhobby..$89
- with OSD and power module
- 1 x Quattro SKY III 30Ax4.................. gadgetinfinite....$34
- 1 x Hobbywing Skywalker Quattro 20 A ESC..gadgetextreme... $35
- 4 x Sunnysky X2212 980 KV brushless motors...flyingxsys......$74
- 1x Metallic folding X frame,...................globalmart.......$20
- 1x Turnigy 9ch TX remote (v2) with RX..........ddosoff..........$75
- 2 x Lipo 3S 2.2AH or 2.6 Lipo Battery..........theaterpopcorn...$20
- IMAX LiPro Balance Charger..................onlytop888. .....$23
- 10x4.5 Propellers 6 x CW 6 x CCW..........TOMTOPUSA........$10
- buy 6, they break 100% in few flights
- New Carbon Fiber Balancer...................gagaoutleteb.....$6
- Female to female jumper cables........maaqii.................$3
- Connector 3mm Gold Plated Male and Female Bullet Banana
- ...................................... blacksmithproducts...$17
- Pair Male and Female T Plug Connectors For Deans RC Lipo Battery
- for helicopter......------.......................alline*a*t.......... $1
- Outdoor double sided tape..............The Home Depot..........$1
- Heat Shrink Tubing.....................smttrade05/sayal......$6
Block DiagramAll components are pretty much connected together as shown.
The APM controller is connected to RX with few female to female jump wires. The power to RX is taken form the APM power line. The GPS+COMPASS module is connected to dedicated connectors to APM board. The Power module is connected to the APM board. The board takes the 5V from the power module. The APM also monitors the current and voltage of the system trough the power module. The 4x1 ESC (Electronic Speed Controller) is connected to the APM to it's outputs. The ESC's module provides 5V power to the APM on the output rails. This power does not interfere with the power given by the power module because there are 2 separate rows of power on the APM. Several add-ons as gimbal, optical flow, FPV and or cameras can be powered from either 2 lines of power form the module.
Turnigy Transmitter SetupTurnigy proper function is required during APM construction. This is not a simple procedure and requires to know the remote pretty well. Try browsing the Turnigy manual for 5 minutes or so.
Different releases of the Remote software might have different menu structure In such case try to find the option by it's name, or look it up in the manual.
Program ACRO Mode
Start from Main Menu
Press MENU, MENU to get to SYSTEM SETTINGS
◦ From SYSTEM SETINGS press DOWN, DOWN to get to TYPE SELECT
▪ From TYPE SELECT selection press MENU, to get to TYPE sub-menu.
▪ You see now 3 options, HELY, ACRO, GRID
▪ Press UP/ DOWN to select ACRO, then press MENU to get back
to SYSTEM SETTINGS then EXIT to get back to MENU
Program reversed Throttle
Start from Main Menu
Press MENU, MENU to get to SYSTEM SETTINGS
◦ From SYSTEM SETTINGS press DOWN,DOWN, DOWN to STICK SELECT
▪ Press MENU to get to STICK sub-menu
From STICK sub-menu press UP/DN to select MODE2
Press MENU, and when TRO REVERSE ?
If you press MENU will reverse the THROTTLE. This option is a bit
confusing, and you have to check it later on with the Flight software.
Just remember how to get here.
▪ Press MENU MENU
Program Reverse Pitch
Start from Main Menu
◦ MENU, MENU - > SYSTEM SETTINGS
▪ In SYSTEM SETTIGNS press DN to FUNC SETTINGS
Press MENU to FUNC SETTINGS 1⁄2
In FUNC SETTINGS1/2 select REVERSE
◦ In REVERSE Select ELE, then with +/- buttons will see
WHITE BLACK and the ELE selection will be on the left bottom corner
select REV, then
◦ Main Menu TUR. The pitch will be reversed. Will come over to this when we will have it all connected.
*** The second part of Turnigy programming is covered in section 6 ***
Pairing TX to RX
- Required tools
- Soldering iron
- Heat-Shrink tubing
- 5V stabilised power supply.
female-female jumper cable as shown.
You should have couple of those from the ESC purchase packaging. Using the
multimeter, make sure the +5V goes to the RED wire is connected to the middle pin.
Turnigy RX pin schematic is: (In the picture the RX module faces with It's LOGO upward)
Connect one female-female jump wire or the pairing Turnigy loop wire supplied with the package in the last row on the right of the RX. Power the RX to any other row from the 5V supply. The black wire (Ground) will go to bottom line of pins. The red wire to middle. Do not invert polarity, or power the outputs (top row). Wrong polarity would damage the RX.
Turn over the TX Remote and hold down the mid button, then with the other hand turn the remote ON.
The TX LED should stop blinking. The remote TX and RX are paired.
ESC 4x1 Calibration and setupSchematic for ESC calibration step 1.
If the motors did not came with the banana male already soldered, solder to each motor the 3 mm male banana. Make sure you heat shrink each banana.
Solder also the LIPO T Plug female battery connector to the ESC power, and the male to the Power Module. Solder the transversal to the red wire (+) and the other (-), longitudinal connector to the black wire (ground or minus).
After having all the above soldered, connect the motors to the ESC. The wiring order does not matter for now. Just be sure you connect each motor 3 wires to 3 grouped wires to the ESC. Do not install any propellers. Connect motors. Don't power the battery to the power module to power the ESC without the motors hooked up.
At this stage yout circuit should look like the initial schematic, without the battery.