This document provides a comprehensive guide on building a quadrocopter, covering operational theory, building blocks, and practical tips. It details the necessary components such as motors, batteries, and controllers, as well as the physics involved in flight dynamics. Additionally, it includes references for further reading and legal considerations for operation.

1. How to build your own QuadrocopterHow to build your own Quadrocopter
Lenz Grimmer <lenz@grimmer.com>
http://www.lenzg.net/
Twitter: @lenzgr
SAPO Codebits 2010, Lisbon, Portugal

2. OutlineOutline
● Basics / Operational Theory
● Building Blocks
● References/URLs
● Demo

3. FeaturesFeatures
● A “VTOL UAV”
● Simple to build
● Simple mechanics
● No servos required
● Parts Availability / Accessibility

4. Lab/Tech RequirementsLab/Tech Requirements
● Soldering station
● Powerdrill / Dremel
● Others (Screwdrivers, Saws, Files)
● Power supply

5. Operational theoryOperational theory
● Physics
● Flight Dynamics
● Movement / Control

6. PhysicsPhysics
● 2 pairs of counter rotating props
● Compensate rotary momentum
● Different RPMs = different thrust

7. Flight DynamicsFlight Dynamics
http://en.wikipedia.org/wiki/File:Flight_dynamics_with_text.png

8. Movement/ControlMovement/Control
● Regular remote control
● Behaves like a helicopter
● Nick / Roll / Yaw
● Up / Down
● “X”, “+” or “Y” flight configuration
● Pilot skills

9. Momentum CompensationMomentum Compensation

10. Yaw/RotationYaw/Rotation

11. Vertical MovementVertical Movement
F F
FF
m·g
4⋅F=m⋅g
4⋅Fm⋅g
4⋅Fm⋅g
Ascending
Descending

12. Nick/RollNick/Roll
F1 F2

13. Nick/RollNick/Roll
F1
F2

14. Building blocksBuilding blocks
● Frame
● Motors
● Propellers
● Battery
● Electronics

15. FrameFrame

16. FrameFrame
● Center plate
● Arms
● Battery mount
● Motor mounts
● Protective dome
● Landing gear

17. PropellersPropellers

18. PropellersPropellers
● Diameter: 8, 10, 12 inch
● 2 blades
● Directly attached to motor
● 2 each rotating CW and CCW
● Proper balance reduces vibrations

19. MotorsMotors

20. Brushed MotorBrushed Motor
+ -

21. Brushless MotorBrushless Motor
Phase A
Phase C
Phase B

22. MotorsMotors
● Brushless
● Outrunner vs. Inrunner
● Direct drive (no transmission)
● 3-phase powered
● Requires special BL controller
● Weight (g) / RPMs/V / max. current (A)

23. Brushless ControllerBrushless Controller

24. Brushless ControllerBrushless Controller
● Converts DC power to 3-phase AC signal
● Drive motor to indicated RPMs
● Controller speed is essential
● Receives RPM info from receiver/control unit
● PWM signal
● I2C
● UART (Serial)

25. BatteryBattery

26. BatteryBattery
● Lithium Polymer (LiPo) (or Lithium Iron
Phosphate, LiFePo4)
● Lightweight
● High currents and capacity
● Handle with care!
● Voltage / Capacity / Max discharge /
Weight

27. Power Distribution / WiringPower Distribution / Wiring
Battery
Motor
BLC
Sensors
Motor
BLC
Motor
BLC
Motor
BLC
RX
Central Control

28. Power DistributionPower Distribution

29. Power DistributionPower Distribution
● Supply the BLCs / Motors
● Supply the central controller / Sensors
● Support high currents
● Main switch or battery plugs
● Wires or PCB

30. Transmitter / ReceiverTransmitter / Receiver

31. Transmitter / ReceiverTransmitter / Receiver
● Frequencies: 35/40 MHz, 2.4 GHz
● Minimum: 4 channels
● Receiver output: PPM (sum signal) or
individual channels from receiver
(PWM)

32. SensorsSensors

33. SensorsSensors
● IMU
● Gyroscopes (Rotation)
● Accelerometers (Movement)
● Optional
● Pressure Sensor (Altitude)
● Compass/Magnetometer (Attitude)
● GPS (Location)

34. Central ControllerCentral Controller

35. Central ControllerCentral Controller
● Collects sensor data
● Receives control commands
● Calculates orientation/location
● Sends updated motor commands to
BLCs
● Microcontroller (e.g. Arduino, ARM...)

36. Configuration SoftwareConfiguration Software

37. AccessoriesAccessories
● Camera mount
● Zigbee for telemetry data
● Video goggles

38. Legal aspectsLegal aspects
● Check local laws for regulations
● Consider getting an insurance

39. Practical tipsPractical tips
● Double-check propeller positions and directions
● Double-check Flight Control orientation
● Avoid vibration where possible for stable flight
● Test outside, away from people
● Don't attach the propellers on the motors until
everything is tested!

40. References / URLsReferences / URLs
● Forums
● RCGroups - http://www.rcgroups.com/
● DIYDrones - http://diydrones.com/
● Portuguese Forum - http://forum.rcmpt.com/
● Projects
● Mikrokopter - http://www.mikrokopter.de/
● UAVP-NG - http://ng.uavp.ch/
● Arm-O-Kopter - http://www.armokopter.at/
● Arducopter - http://code.google.com/p/arducopter/
● Aeroquad - http://aeroquad.com/
● KK-Multicopter - http://kkmulticopter.com/
● OpenPilot - http://openpilot.org/
● Quadrocopter and Tricopter Info Mega Link Index
http://www.rcgroups.com/forums/showthread.php?t=1097355

41. References / URLsReferences / URLs
● Parts
● HobbyKing -
http://www.hobbyking.com/
● SparkFun - http://www.sparkfun.com/
● DIYdrones - http://store.diydrones.com/