presentation of auto pilot

8/6/2019 Presentation of Auto Pilot

1/43


2/43

The Contents..

U1


3/43

Slide 2

U1 USER, 7/20/2011


4/43

Introductiony The AFS in aircraft is designed to reduce the workload of

the flying crew, improve regularity of the f light andto improve safety of the.

y The basic functions of the AFS are yaw damper, ruddertrim, rudder travel limitation, flight envelope protectionetc flight.

y The complete auto flight systems can be classified intotwo main systems.

y Flight management guidance systems

y Flight augmentation systems


5/43

When the AFS is not active, the above mentioned components arecontrolled by the same systems but orders are generated by specificdevices i.e., side sticks and thrust levers

The way to use AFS is to follow the flight plan automaticallyknowing the position of the aircraft and the flight plan chosen

by the pilot ,the system is able to compute the orders sent to

the flying surfaces and the engines so that the aircraft follows

the flight plan. The schematic of the AFS of a modern aircraftis shown in the figure1.3.


6/43

The basic functions of the Flight augmentationcomputers (FAC) are the rudder control and the f lightenvelope protection

The basic functions of the Flight Augmentation Computer

(FAC) are:

1. Yaw Damper

2. Rudder trim

3. Rudder travel Limitation

4. Flight Envelope Protection

The main objective is to design an auto flight system,which is used in the Unmanned Aerial vehicles and insmall aircrafts as a cost effective measure and fly theaircraft automatically

Having throttle control altitude is the default, for safety if theengine fails.


7/43

Types of Automatic Control SystemBased on the tasks level of difficulty, the Automatic Flight ControlSystem can

be categorized into four different types:1. AFCS as the trimmed flight holding system2. AFCS as the stability augmentation system3. AFCS as the command augmentation system4. AFCS as the stability maker and command optimization


8/43


9/43


10/43

utopilot architect

ure


11/43

4. The autopilot computer processes theinput data and determines that the wings areno longer level.5. The autopilot computer sends a signal tothe servos that control the aircraft's ailerons.

The signal is a very specific command tellingthe servo to make a precise adjustment.

Some airplanes even have autothrust

computers to control engine thrust.Autopilot and autothrust systems can worktogether to perform very complexmaneuvers.


12/43

5. The autopilot computer sends a signal to theservos that control the aircraft's ailerons. The

signal is a very specific command telling the servoto make a precise adjustment

6. Each servo has a small electric motor fitted witha slip clutch that, through a bridle cable, grips theaileron cable. When the cable moves, the controlsurfaces move accordingly.

7. As the ailerons are adjusted based on the input

data, the wings move back toward level.8. The autopilot computer removes the command

when the position sensor on the wing detects that

the wings are once again level.


13/43

9. The servos cease to apply pressure on the aileroncables.

This loop, shown above in the block diagram,works continuously, many times a second, muchmore quickly and smoothly than a human pilotcould. Two- and three-axis autopilots obey the

same principles, employing multiple processorsthat control multiple surfaces.


14/43


15/43


16/43


17/43

Ardunio Platform


18/43


19/43

Parallax BASIC Stamp chip:OverviewofBasic Stamp UA


20/43

Parallax Propeller chip:AttoPilot, a powerful and inexpensivecommercial autopilot


21/43

TheARM7 (using the Philips LCP214x chip)is the core of the open source Paparazzi

project:


22/43

ARM7 on SparkFun development board:


23/43


24/43

Yoke -Autopilot disconnect button


25/43


26/43


27/43


28/43


29/43


30/43


31/43


32/43


33/43

Hawk Missile AutopilotHawk missile autopilot, Raytheon, 1960


34/43

t t i


35/43

operate e evators an ru er ai eronswerenot connected as wing dihedralwas countedupon to produce the necessary roll stability.)It permitted the aircraft to fly straight andlevel on a compass course without a pilot's

attention, greatly reducing the pilot'sworkload.Lawrence Sperry(the son of famousinventor Elmer Sperry) demonstrated it twoyears later in 1914 at an aviation safetycontest held in Paris. At the

contest, Lawrence Sperrydemonstrated thecredibility of the invention were shown byflying the aircraft with his hands away fromthe controls and visible to onlookers of thecontest. This autopilot system was alsocapable of performing take-off and landing,

and the French military command showedimmediate interest in the autopilotsystem.Wiley Post used a Sperry autopilotsystem to fly alone around the world in lessthan eight days in 1933.Further development of the autopilot wereperformed, such as improved controlalgorithms and hydraulic servomechanisms.


36/43

ienthals Flyerable Flight

Wright FlyerUnstable Flight


37/43


38/43


39/43


40/43


41/43


42/43

A320 Flight Control Laws Improve the natural flying qualities, particularly the stability,control and flight envelope protection.Longitudinal Control Load factor demands Classical proportional plus integral control (control dependson error and its integral)30 / 71Lateral-directional Control Roll rate, sideslip and bank angle commands Classical proportional plus integral control with a gain matrixfor stability and roll rate/sideslip decoupling


43/43

presentation of auto pilot

Documents