This document summarizes the design, modeling, components, and control strategy of a quadcopter unmanned aerial vehicle. Key aspects include: 1) It uses four propellers powered by brushless DC motors for vertical take-off and landing, with yaw, roll, and pitch control achieved by varying motor speeds. 2) An IMU, microcontroller, and PID controllers provide attitude estimation and motor control. 3) A complementary filter fuses gyroscope and accelerometer data to estimate orientation with drift correction. 4) Wireless transmission of sensor data and live video enable remote control and monitoring of flight.

2. Design
Fabrication
Stabilization

3. Applications
Remote Data Acquisition
Rescue Operation
Indoor and Outdoor Flight
Surveillance

4. Modeling
Mechanical Design
Sensors and Actuators
Signal Conditioning
Control Strategy

5. An aircraft that is lifted and propelled by four
propellers.
Control and maneuvering is achieved by
varying the relative speeds of the four
rotors.
Vertical Take Off and Landing

6. Yaw
Roll/Pitch

7.  PRO-E simulation was used to determine:
 Dimensions of the craft (0.25 m).
 Total mass (1.5 kg) of the PVC structure
 Moment of inertia (0.025 kg.m2) .
 Propeller size (9 inch).
 The results obtained enabled us to select a suitable BLDC motor for the
quad rotor.

8.  9 Degrees of Freedom - Razor IMU ( Sparkfun.com)
 Specifications of IMU.
 LY530ALH (300°/s single-axis gyro),
 LPR530ALH (300°/s dual-axis gyro),
 ADXL345 (three-axis accelerometer),
 HMC5843 (three-axis magnetometer)

9.  BLDC motor - out runner (the outer shell spins) is used
 Specifications:
 Weight: 56g
 Voltage: 10V
 KV: 1200 RPM/V
 Max Efficiency Current: 15.5A
 Max Power out: 180W.
 An electronic speed controller (ESC) is used
to control the speed of electric motors.
 It is a pulse-width modulation (PWM) controller
Turnigy Bell 2409-18T

10.  Two 2200mAh 3S 25C Lipo Packs and a separate
battery used for electronic circuitry.
 Size: 9 x 5
 Clockwise and Counter-Clockwise orientation.

11.  dsPIC 30f5015 motor control series microcontroller
for onboard computation.
 All calculations were done in fixed point (signed Q15.16)
 Capable of providing 4 simultaneous independent PWM’s
 dsPIC features, hardware multiplier, 16 bit architecture
 Operating with a clock multiplier to obtain 14MIPS.

12. User
PC
(ground station)
Transceiver
Base Station
Transceiver
Camera
(wireless)
Motors
Gyroscopes
Accelerometers
Magnetometer
Pressure
Sensor
Quadrotor
Attitude
PID
Angle
Estimate
Correction
Translation
PID
Reference
Microcontroller

13.  IMU data is corrupted and has to be filtered to make it usable.
 Gyro integration gives orientation but drifts over time.

14.  Accelerometer gives the gravity vector.
 Integration of rate gyros gives attitude.
 Noise in gyros:
 Offset
 White noise
 Leads to drift
 The ‘g’ reference vector from the accelerometer is used to correct this drift

15.  The gyro is integrated to give the roll and pitch.
 obtain the calculated ‘g’ vector.
 The error between the measured and calculated ‘g’ vector is adjusted into the
gyro data.
Gyroscope
(rad/unit time)
Compensation
Roll/Pitch
angle
Accelerometer
(rad/unit time)
Error PID
Cross Product
Integration
Estimated ‘g’
vector

16.  Results from Complimentary Filter

17.  Two options for orientation estimation
 The Complimentary Filter:
 does not require the system model
 is optimized for microcontroller implementation
 performance is comparable to the Kalman Filter
Kalman filter Complimentary filter

18.  PID controller was used for roll and pitch control.
 Larger P leads to faster response,
 I used for reference tracking
 D dampens the oscillations, reduces overshoot
 A simulation was done using the mathematical model in MATLAB.
 The gains found were fine tuned on the actual system

19.  Objective:
 Sensing translation in X- axis
 Sensing translation in Y- axis
 Yaw computation

20.  Wireless camera over IP are very expensive.
 Camera of the smart phone was used for live streaming.
 Bluetooth link was used between the camera and the base station.
 A Red Cross of the ground was used as reference for determining
the position of the craft.

21. Image
Acquistion
Image
Segmentation
Blob Detection
Blob Filtering
& Analysis
Centroid &
Yaw
Evaluation
Error
Computation

32. Translation control
Wireless communication
Ultra sonic sensor for object
avoidance

35. Q & A
Thank
You !