This document summarizes two avionic control systems implemented as educational tools: the Seesaw Control System (SCS) and Quadrotor Control System (QCS). The SCS uses a PID controller and sensors to stabilize a seesaw at a desired tilt angle. The QCS is designed to teach embedded programming for quadrotor drones using an IMU, brushless controllers, and microcontroller over I2C communication. Both systems provide hands-on learning experiences for control systems and applications in avionics.

1. Presented By:
Fahad Ali Amjad 12063122-027
Abdullah Mir 12063122-039

2.  This paper includes two avionic control systems.
 Implemented as educational tools in the study path of
Information Technology for Aerospace.
 They are used in ongoing development and research projects.

3.  These exercise systems are SCS & QCS.
 SCS means SEESAW CONTROL SYSTEM
 QCS means QUADROTOR CONTROL SYSTEM

4.  SCS task is to stabilize the system at desired tilt angle
and angular rate.
 To improve the system response by tuning the
controller parameters.
 Sensors are used to measure the actual output of the
system and feed this information back to the
controller.
 The controller uses this information to adjust the
signal of the system accordingly.

5.  3-Axis accelerometer sensor (MMA7361L)
 Driver IC for dual DC motors (TB6612FNG H-Bridge)
 Data acquisition unit (NI USB-6008)

7.  Software of the SCS is implemented using LabVIEW
and can be used in two main controlling tasks.
 In order to stabilize the system around a desired tilt
angle, a (Proportional Integral Derivative) PID
Controller is used to control the rotational speed of a
single motor.
 In case of two motors, the PID controller will
calculate the required ratio needs to be increased and
decreased respectively for stabilizing the system
around a desired tilt angle.

8.  The calibration of sensor is used to improve the quality of
data.

9.  SCS includes how the output of the PID controller
adjusts itself to the required input for stabilizing the
system around a desired point.

10.  The main idea of the QCS was to design a tool to
learn embedded programming in a real time
environment using an application from Avionics.
 In QCS, the students can do implementation step by
step and test their own control algorithm to stabilize
the system and later to use it in real flying quadrotors.

11.  Microcontroller UC3A Atmel.
 IM (Inertial Measurement Unit) consisting of
the ITG3200 gyroscope and the ADXL345
accelerometer.
 Four brushless controllers using the I²C.
 Uses I²C to connect all peripherals on one
bus.
 Minimum number of wires and drivers to run
the system.

13.  Components like magnetic compass, infrared,
ultrasonic and pressure sensors can be added
using the I²C bus.
 The microcontroller provides enough I/O
lines to connect all other kind of peripheries
like Bluetooth, Wifi, Camera, GPS etc.

14.  Software is designed using the Atmel
Framework (Technical Library) within AVR32
Studio.
 We can implement all levels of the softwares
to create I²C (Inter-Integrated Circuit),USART
(Universal Synchronous Asynchronous
Receiver Transmitter) etc over communication
protocols.

15.  The control loop operates on a sample time
10ms, fast enough for a very stable control
behavior in this application.
 The microcontroller could even handle a
faster sample time.

16.  Mechanical design involves different versions
of implementation and parameterizing of
each controller for all axes separately.
 In the first version, all parts of the tri-axial
controller including its parameters and
algorithm can be tested separately and
altogether.
 In the second version, the quadrotor can
manipulate its orientation in all 3 rotation
axes without changing the position meaning
the 3 translational axes.

18.  The QCS proved to be a successful learning
tool and was able to control and fly the
quadrotor.
 Nevertheless for an optimized flight the PID
parameters had to be adapted.
 One big issue of this approach was the use of
I²C.

19.  Autonomous Flying Robots, Spring 2010, Kenzo Nonami
 Introduction to Feedback Control Theory, CRC Press 1999, Hitay Özbay,
ISBN: 084931867X
 LabVIEW for Everyone, Prentice Hall 2005, James Kring, and Jeffrey
Travis, ISBN:0131856723
 AT32UC3A Series Preliminary, Datasheet Online Accessed January 2012,
http://www.atmel.com/dyn/resources/prod_documents/32058S.pdf
 Igus GmBH, http://www.igus.de