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Quadrotor Control Project Based On AR.Drone
Supervisor: Dr M.ZQ.Chen
U.ID : 2011955028
GAO Mingze, Frank
Mar 13, 2013
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
1, Background Introduction 2, Theoretical basis 2.1 Quadrotor Dynamics 2.2 Controller Design & Simulation 3, Platform Construction 3.1 OS transplantation 3.2 Sensing-Tech 4, On-Going Focus 5, Future Plan 6, Q&A 7, Reference Slides for Q&A
Outline:
Background Introduction Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Quadrotor: Classified as rotorcraft which is lifted and propelled by four rotors.
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Control of the quadrotor motion is achieved by altering rotation rate of one or more rotor propellers, thereby changing its torque load and thrust/lift characteristics. In this FYP, my concentration is mainly placed on position control
Background Introduction
To achieve the goal of a precision flight attitude control on quadrotor, we need to build the dynamic model.
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Theoretical Basis
Quadrotor Dynamic Model
Basic theory of the optimization control on quadrotor vehicle
Assumptions: Quadrotor body is rigid
Propellers are rigid
Design is symmetrical
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Quadrotor Dynamics
Frame of reference:
: an body fixed frame with mutally orthogonal axes x,y,z with unit vector and i,j and k.
E: earth fixed frame
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Motor Position:
Quadrotor Dynamics
Pitch, Roll and Yaw Angle
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Euler angles of the body axes are {e1, e2, e3} with respect to the body-Frame axes, respectively, and are referred to as pitch, roll and yaw. { φ, θ, ψ }
Quadrotor Dynamics
Forces acting on Quadrotor
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
The center of mass is located at the origin of the -Frame. The imbalance of the force F results in moment, along the direction perpendicular to the plane formed by force F and the vector L
Quadrotor Dynamics
Inertia Moment
In derivation of moment of inertia along x (and y) axis, the following assumptions are made:
1, Motors M1 and M3 are cylindrical in shape with radius ρ, height h and mass m.
2, Central hub or body of quadrotor is also cylindrical with radius R, height H and mass 𝑚0.
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Quadrotor Dynamics
After a simple calculation, we may get the inertia moment in x,y,and z direction respectively
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Quadrotor Dynamics
𝑰𝒙𝒙 =𝟏
𝟐𝒎𝝆𝟐 +
𝟏
𝟔𝒎𝒉𝟐 + 𝟐𝒎𝒍𝟐 +
𝒎𝟎𝑹𝟐
𝟒+𝒎𝟎𝑯
𝟐
𝟏𝟐
𝑰𝒚𝒚 =𝟏
𝟐𝒎𝝆𝟐 +
𝟏
𝟔𝒎𝒉𝟐 + 𝟐𝒎𝒍𝟐 +
𝒎𝟎𝑹𝟐
𝟒+𝒎𝟎𝑯
𝟐
𝟏𝟐
𝑰𝒛𝒛 =𝟏
𝟐𝒎𝟎𝑹
𝟐 + 𝟒𝒎𝒍𝟐
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Under the gravity and actuator action without other external effects, the machine experiences following motions: 1, Rolling along x-axis 2, Pitching along y-axis 3, Yaw motion along z-axis:
Dynamics of Quadrotor:
As the focus is on the hover control of quadrotor, and the fact that horizontal motion is a consequence of rotational motion, the following relations are developed.
Quadrotor Dynamics
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Rolling motion is about x-axis. (Rolling Dynamic) Rolling angular displacement as measured with respect to E-Frame using right hand rule is θ. There θ” expresses angular acceleration about x-axis. Based on the moment of inertia of machine about x-axis, the rolling torque on machine is:
Also due to the design of machine, the rolling torque is due to the thrust difference of motors M2 and M4 and the thrust force of each motor is assumed to be perpendicular to the plane of propeller and therefore the plane of quadrotor frame. Therefore the rolling torque is :
Quadrotor Dynamics
𝑰𝒙𝒙𝜽 × 𝒊 = 𝒍(𝑭𝟐 − 𝑭𝟒) × 𝒊
𝝉𝒙𝒙 = 𝑰𝒙𝒙𝜽 𝒊
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Similarly, the pitching motion is along the y-axis and the relationship can be easily found as following:
It can be easily found that both the rolling and the pitching motion have a closed relationship with the force Fi ( i=1,2,3,4 ). And according to the property of the DC motors, the force is controlled by the rotation rate of the propeller. Mainly the Yaw Dynamic happens on the X-Y coordinate plane. Compared to rolling and pitching control, a more precise control of the rotating speed should be achieved in raw control, which is not applicable if AR.Drone is used as the platform in this project.
(Pitching Dynamic)
Quadrotor Dynamics
𝑰𝒚𝒚𝝓 = 𝒍(𝑭𝟏 − 𝑭𝟑)
(Yaw Dynamic) *discussed in the reference slides (Ignore)
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
In this FYP, more efforts were placed on pitching and rolling control. According to the symmetrical assumption we made, for the symmetrical rolling and pitching motion, no net torque(theoretically) will be generated along the z axis.
Hover Yaw Pitch & Roll
Quadrotor Dynamics
Influence of ignoring the Yaw Motion
All Done!!! Let`s start to design the controller!!!
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Pitching & Rolling Control:
Controller Design & Simulation
Quadrotor rolling dynamics:
𝑰𝒙𝒙𝜽 × 𝒊 = 𝒍(𝑭𝟐 − 𝑭𝟒) × 𝒊
𝟏
𝟐𝒎𝝆𝟐 +
𝟏
𝟔𝒎𝒉𝟐 + 𝟐𝒎𝒍𝟐 +
𝒎𝟎𝑹𝟐
𝟒+𝒎𝟎𝑯
𝟐
𝟏𝟐× 𝜽 = 𝒍 𝑭𝟐 − 𝑭𝟒
According to propeller aerodynamics:
𝑭 = 𝑲𝒎 𝒓 × 𝒏𝟐 (n is the rotating speed of the propeller) Initial stable condition: Not a Big Deal, Calculate Just For Fun
𝟒 × 𝑲𝒎 × 𝒏𝟎𝟐 = (𝒎𝟎 + 𝟒𝒎)𝒈 𝒏𝒐 =
𝟏
𝟐
(𝒎𝟎+𝟒𝒎)𝒈
𝑲𝒎
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Controller Design & Simulation
Pulse signal with width of U (lasts for 1000-2000 s)
Propeller rotating speed N (lasts from 0-180 r/s)
Controller DC Motor
First order object
𝐍(𝐬)
𝐔(𝐬)=
𝑻𝒇
𝐬+𝟏 in which Tf = 0.18
(Time constant is set to be 1s for the simulation process)
Transfer function between the rotating speed and the pulse signal width
Commands Action
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Controller Design & Simulation
When there is a command sent to the controller: (∆𝐧)
𝐅 = 𝟒 × 𝑲𝒎 𝒏𝟎 + ∆𝐧 𝟐 = 𝟒 ×𝑲𝒎 𝒏𝟎𝟐 + ∆𝒏𝟐 + 𝟐𝒏𝟎∆𝒏
≅ 𝟒𝑲𝒎𝒏𝟎𝟐 + 𝟖𝑲𝒎𝒏𝟎∆𝒏
𝟏
𝟐𝐦𝛒𝟐 +
𝟏
𝟔𝐦𝐡𝟐 + 𝟐𝐦𝐥𝟐 +
𝐦𝟎𝐑𝟐
𝟒+𝐦𝟎𝐇
𝟐
𝟏𝟐× 𝛉 𝐬 × 𝐬𝟐 = 𝟖𝐊𝐦𝒍𝐧𝟎𝐍 𝐬
𝑰𝒙𝒙𝜽 × 𝒊 = 𝒍(𝑭𝟐 − 𝑭𝟒) × 𝒊
𝛉(𝐬)
𝐍(𝐬)=𝟖𝐊𝐦𝒍𝐧𝟎𝐈𝐱𝐱𝐬
𝟐
𝐍(𝐬)
𝐔(𝐬)=
𝑻𝒇
𝐬 + 𝟏
𝜽(𝒔)
𝑼(𝒔)=
𝑪𝟎𝑻𝒇
𝒔𝟐(𝒔 + 𝟏) (𝒄𝟎 =
𝟖𝑲𝒎𝒍𝒏𝟎𝑰𝒙𝒙
)
Also we have :
Then we finally get:
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Controller Design & Simulation
In last equation, 𝐶0 should be tested through the experiment. For the following simulation part, we simply set 𝐶0𝑇𝑓 equals to 20 (a
rough prediction, a more precise value will be given in the report),
the unit of 𝜃 is degree (180º) and the unit of U is s. For the system, we have: Gp(s) =
𝐶0𝑇𝑓
𝑠2(𝑠+1) =
20
𝑠2(𝑠+1)
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Controller Design & Simulation
PD Control:
Open-loop transfer function:
H(s) = Gc(s)*Gp(s) = 𝑲𝒑 𝟏 + 𝑻𝒅𝒔 × 𝑪𝟎𝑻𝒇
𝒔𝟐(𝒔+𝟏)
First we need to find the range of variation, we simply set 𝐾𝑝
equals to 1, the characteristic function of the closed loop function indicates that: 𝒔𝟑 + 𝒔𝟐 + 𝟐𝟎𝑻𝒅𝒔 + 𝟐𝟎 = 𝟎
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Controller Design & Simulation
To plot the root locus diagram for the system, we know that we should plot the roots distribution for the function:
𝟏 + 𝐊 × 𝐇 𝒔 = 𝟎 (for K varies from 0~)
* When we backstep the characteristic function, we may form a new open-loop transfer function. Treat the character 𝑇𝑑 as the K in the root locus diagram, by root locus method, we may find the critical 𝑇𝑑 which makes the system stable.
𝒔𝟑 + 𝒔𝟐 + 𝟐𝟎𝑻𝒅𝒔 + 𝟐𝟎 = 𝟎
New open-loop transfer function:
With the same characteristic function:
G s = 𝑇𝑑 ×𝑁∗ 𝑠
𝐷∗ 𝑠 𝑇𝑑𝑣𝑎𝑟𝑖𝑒𝑠 𝑓𝑟𝑜𝑚 0~
𝑁∗= 20𝑠 ; 𝐷∗ = 𝑠3 + 𝑠2 + 20
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Controller Design & Simulation
Then the critical 𝑇𝑑 we got from the root locus is exactly 𝑇𝑑 which will makes the system stable.
Root locus diagram: >> num=[21.3,0]; >> den=[1 1 0 21.3]; >> rlocus(num,den);
Which means that the gain (𝑇𝑑) must be greater than 1 to make the whole system stable.
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Controller Design & Simulation
The nyquist diagram of the open loop transfer function is used to test such results:
>> num=[19.4,20]; >> den=[1,1,0,0]; >> nyquist(num,den); >> axis([-2,1,-0.05,0.05]); >> hold on; >> num1=[20.6,20]; >> nyquist(num1,den);
In this diagram, the blue line represents for the situation in which td=0.97 and the green line represents for the situation in which td=1.03. The change of the direction shows the change of the system stability.
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Controller Design & Simulation
Disturbance:
>> num=[20]; >> den=[1,1,100,50]; >> step(num,den);
We treat the disturbance in form of the change of the rotating speed of the propeller.
A step disturbance response Kp = 2, Td=2.5
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Controller Design & Simulation
PD controller simulation:
>> kp=2; >> td=2.5; >> s=tf('s'); >> gc=kp*(1+td*s); >> gp=20/s/s/(s+1); >> t=0:0.01:30; >> u=linspace(1,1,length(t)); >> y=lsim(gc*gp/(1+gc*gp),u,t); >> n=linspace(5,5,length(t))+5*rand(1,length(t)); >> yn=lsim(gp/(1+gc*gp),n,t); >> plot(t,y+yn); Not a good control!!!
Random disturbance
A step disturbance response Kp = 2, Td=2.5
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Controller Design & Simulation
PID control:
The open loop transfer function:
𝑮(𝒔) =𝑪𝟎𝑻𝒇𝑲𝒑(𝑻𝒊𝑻𝒅𝒔
𝟐 + 𝑻𝒊𝒔 + 𝟏)
𝑻𝒊𝒔𝟑(𝒔 + 𝟏)
In which set 𝐾𝑝 = 2, 𝑇𝑑 = 2.5, and also set 𝐶0𝑇𝑓 = 20
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Controller Design & Simulation
The characteristic function indicates that:
𝑇𝑖𝑠4 + 𝑇𝑖𝑠
3 + 100𝑇𝑖𝑠2 + 40𝑇𝑖𝑠 + 40 = 0
With the same characteristic function, we could also find the new transfer function which satisfies the form of root locus. Also by plotting root locus diagram we may find the critical 𝑇𝑖 which will stabilize the system.
G s = 𝑇𝑖 ×𝑁∗ 𝑠
𝐷∗ 𝑠 𝑇𝑖 𝑣𝑎𝑟𝑖𝑒𝑠 𝑓𝑟𝑜𝑚 0~
𝑁∗= 𝑠4 + 𝑠3 + 100𝑠2 + 40𝑠; 𝐷∗= 40
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Controller Design & Simulation
Root locus diagram: >> num=[1,1, 100,40,0]; >> den=[40]; >> sys=tf(num,den); >> rlocus(sys); >> axis([-2,2,-10,10]);
From the diagram we could see that to make the system stable, 𝑇𝑖 should be larger than 0.0157
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Controller Design & Simulation
Random select some values for the controller:
Set Kp=2, Ti=10, Td=2.5, and get the step response as the following:
(Without disturbance just to make sure the estimation of 𝑇𝑖 is correct)
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Controller Design & Simulation
Still the same 𝐾𝑝, 𝑇𝑑 and 𝑇𝑖, with a 5 random disturbance, the step
response is shown:
>> kp=2; ti=10; td=2.5; s=tf('s'); gc=kp*(1+1/ti/s+td*s); gp=20/s/s/(s+1); g=gp*gc/(1+gc*gp); t=0:0.01:60; r=linspace(1,1,length(t)); y=lsim(gc*gp/(1+gc*gp),r,t); n=linspace(1,1,length(t))+rand(1,length(t)); yn=lsim(gp/(1+gc*gp),5*n,t); plot(t,y+yn);
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Controller Design & Simulation
Optimized PID: Set Kp=0.00056, Ti=281, Td=47,
AR.Drone Platform
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Platform Construction
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
OS transplantation
With the Apps downloaded from the App store one can control the AR.Drone to do some simple movements.
Apps flying!!!
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
OS transplantation
An example of AT.Command :
My little control panel:
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
OS transplantation
Flying on Control Panel
At the latter part of the video, an open-loop path following command was sent to the Drone. We could find the drone follow the particular path. It just shows such panel has a good control of the drone.
Some limits:
• Control delay
Unfortunately, this cannot be solved because of the limits of AR.Drone. The frequency of its sending and receiving data has already been set to 30Hz. Only if to modify the hardware can we get a better result.
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
OS transplantation
• Position float
As a mature product, AR.Drone has alerady been programmed. The design of AR.Drone is mainly for entertainment and for such reason, the flight position control part of AR.Drone is not that stable. In order to design and build a quadrotor control platform we need to make some modifications to AR.Drone.
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
OS transplantation
1, Angular velocity : gyroscope, compass
2, Angular acceleration: Digital Accelerometer
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Sensor:
Sensing-Tech
ADXL345 MPU 6050 MiniIMU
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Sensing-Tech
Arduino and X-Bee module:
Programmed in Arduino:
Arduino is an open-source electronics platform based on flexible, easy-to-use hardware and software.
Arduino UNO: X-Bee:
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Through the I2C digital interface and based on IEEE 802.15.4 protocol, we could get the data flow of the accelerometer.
Sensing-Tech
Wire control_MiniIMU Wireless Sensor ADXL345
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
It seems that we have already had a closed control loop, while there is still one more thing to do, the data flow transfer
controller
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Compatibility of the whole system.
( I2C TDMC(LabView) C# )
( I2C .txt C# )
My now working focus and problem:
Too Slow
Quadrotor Control Panel : VC2010, C# input or hardware input Microcontroller of sensors: Arduino, I2C digital interface
On-going Focus
Future Plan:
• Seeking for ways to solve the problem of compatibility and data processing.
• Hardware integration simulation test
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Future Plan
Q&A
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Q&A
Thanks !!!
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
The moment of inertia of two identical cylinders connected together by a horizontal arm , and rotating about a vertical axis, which is passing through the center of the arm and is perpendicular to it, as specified is:
For part a, the moment of inertia due to motors M2 and M4 rotating about x-axis is approximated by
For part b, the moment of inertia due to M1, M3 and the central hub about x-axis is approximated by
Quadrotor Dynamics
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Therefore the total moment of inertia along x-axis is:
The above is the inertia about x-axis. By exactly similar procedure moment of inertia about y-axis can be found that:
Quadrotor Dynamics
𝑰𝒙𝒙 =𝟏
𝟐𝒎𝝆𝟐 +
𝟏
𝟔𝒎𝒉𝟐 + 𝟐𝒎𝒍𝟐 +
𝒎𝟎𝑹𝟐
𝟒+𝒎𝟎𝑯
𝟐
𝟏𝟐
𝑰𝒚𝒚 =𝟏
𝟐𝒎𝝆𝟐 +
𝟏
𝟔𝒎𝒉𝟐 + 𝟐𝒎𝒍𝟐 +
𝒎𝟎𝑹𝟐
𝟒+𝒎𝟎𝑯
𝟐
𝟏𝟐
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Moment of inertia about z-axis, can also be calculated in two parts: 1, Moment of inertia due to central hub. 2, Moment of inertia due to motors M1, M3, M2 and M4.
The total inertia about x,y,z-axis are:
Quadrotor Dynamics
𝑰𝒙𝒙 =𝟏
𝟐𝒎𝝆𝟐 +
𝟏
𝟔𝒎𝒉𝟐 + 𝟐𝒎𝒍𝟐 +
𝒎𝟎𝑹𝟐
𝟒+𝒎𝟎𝑯
𝟐
𝟏𝟐
𝑰𝒚𝒚 =𝟏
𝟐𝒎𝝆𝟐 +
𝟏
𝟔𝒎𝒉𝟐 + 𝟐𝒎𝒍𝟐 +
𝒎𝟎𝑹𝟐
𝟒+𝒎𝟎𝑯
𝟐
𝟏𝟐
𝑰𝒛𝒛 =𝟏
𝟐𝒎𝟎𝑹
𝟐 + 𝟒𝒎𝒍𝟐
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Reference Slides
Ziegler method
function [num,den,Kp,Ti,Td,H] = Ziegler_std( key,vars ) %Ziegler method to determine the parameter of PID controller % Detailed explanation goes here Ti=[]; Td=[]; H=[]; K=vars(1); L=vars(2); T=vars(3); a=K*L/T; if key==1,num=1/a; else if key==2,Kp=0.9/a;Ti=3.33*L; else if key==3,Kp=1.2/a;Ti=2*L;Td=L/2; end end end
switch key case 1, num=Kp; den=1; case 2, num=Kp*[Ti,1];den=[Ti,0]; case 3, p0=[Ti*Td,0,0]; p1=[0,Ti,1]; p2=[0,0,1]; p3=p0+p1+p2; p4=Kp*p3; num=p4/Ti; den=[1,0]; end end
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Yaw Dynamic * (less important in position control) Yaw motion is due to torque imbalance. A net torque about z-axis is responsible for yaw motion in accordance with right hand rule. Each motor supplies machine torque and drag torque. The net torque on propeller is:
J is the rotational inertia of the rotor and propeller of motor. If all the clockwise and counter-clockwise torques are added, the sum torques and the yaw torque can be expressed as:
Reference Slides
Not a toy. But a powerful working platform
• With the user guide published, more things could be done to AR.Drone.
• We can control the drone by
sending an AT.Command to Drone
through UDP port 5554
• The language of AR.Drone:
AT.Command
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Reference Slides
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Demonstration test of MiniIMU
MiniIMU = STM32F103 a popular low-power microcontroller + MPU-6050 accelerometer + HMC5883L compass + BMP085 barometer
Integration chips
Reference Slides
The connection between computer and MiniIMU
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
to
Reference Slides
A wonderful user interface
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Reference Slides
But …..
• Even though such sensor bench works, while it has a “tail”. We cannot fix a USB-TTL line on the quadrotor to transmit the data. We need to build a wireless sensor bench to get the flight attitude.
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Reference Slides
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
New sensor, less powerful but can work in wireless way
ADXL 345: A 3-axle accelerometer with a measurement up to 16g. Digital output data is formatted as 16-bit twos complement and is accessible through I2C digital interface.
How to make it a wireless one?
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• About the chip : Arduino
Arduino is an open-source electronics platform based on flexible, easy-to-use hardware and software.
Arduino Mega 2560: http://www.arduino.cc/en/Main/ArduinoBoardMega2560
The language of Arduino: http://arduino.cc/en/Reference/HomePage
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Reference Slides
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
* X-CTU is the compiler (a software to read and send the data to X-bee) of Digi Company. We can read the data sent beck from the X-bee and then such data will be shown inside the software. 64-bit system × 32-bit system √
As a commercial software in which the data cannot be picked, the X-CTU is not applicable in this project and we need to read the data flow directly from the port with Arduino-UNO. Work about the data flow picking has already been solved. And Now we can read the data in Arduino Development environment.
Reference Slides
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Vertical Acceleration
When the roll or pitch angle is nor zero then a component of F*cosθcosφ acts along the z-axis
Then we will get that:
As we discussed before, Fi will be influenced by the speed of the propeller. Unfortunately for AR.Drone, the speed of the propeller has been well controlled. We could only choose some particular speed gear. (10 gears)
Vertical Position Control
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Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
A proportional derivative controller is going to be designed. We can control the motion along x-axis with a PD controller given by
The desired pitch angle can be written as
Derivative of pitch angle, gives the desired pitch angle velocity
= = 0 ( )
Pitching and rolling control
U-pitch input = (F3 – F1)*d
(Geometrical Pitching)
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Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Likewise, the system rolling input could also be set as(same Kp and Kd)
For the Yaw angle, considering the angle velocity and acceleration, the system input could be set as
Simulation and experiment are under designed…
* Yaw Control
Reference Slides
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
2, Feasibility of the controller design
I can use LabView or MATLAB Simulink to conduct a simulation of the controller design, while it may not has a significant influence on the flight attitude or even cause a chaos in the flight attitude control: AR.Drone is a mature product, and my control panel is based on the user guide, which means each of my commend has already been compiled by AR.Drone and each commend represents a series of movement. The controller nearly has no effect.
Ongoing Focus
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Reference Slides
Quadrotor Control Project
Final Year Project of GAO Mingze (No.2011955028)
Reference Slides
http://en.wikipedia.org/wiki/Quadrotor
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