PC Based Camera Tilt-pan
System and Target Coordinate
Calculation
STUDENT:
G/C BADAR
ADVISER:
S/L OMAR BASHIR
CO-ADVISER:
S/L SOHAIL
BACKGROUND
Fixed camera was used previously that will
be replaced by tilt pan system.
Zooming was controlled mechanically by
moving zooming button on the camera. It
was unreliable, unsafe and insufficient. It
will be replaced by digital system.
AIM
1. To generate control signals for Tilt Pan
movement and zooming of the camera
on the UAV.
2. Receive GPS data and camera position
from control station and transmit camera
control signals to control station via
LAN.
3. Display video along with approximate
target coordinates using Tilt, Pan angles
and GPS data.
SOFTWARE ANALYSIS
Control signals.
Joystick and keyboard.
Camera control.
Target coordinate calculation.
Transmission an reception via LAN.
Video display.
CAMERA CONTROL
SIGNALS(TILT-PAN)
1.
2.
3.
4.
5.
6.
7.
8.
Clockwise pan rotation.
Counter clockwise pan rotation.
Stay pan.
Positive tilt(Towards nose).
Negative tilt(Towards tail).
Stay tilt.
Zero position.
Horizon.
TEST OF SIGNALS FOR
ZOOMING
Uses serial port connection and VISCA protocol
to control various properties.
Demonstrate that camera can be controlled by
any software that conforms to VISCA protocol.
Selection of signals that requires minimum
transmission between ground and airborne
stations.
Using same logic, program the micro controller
in the UAV to control zooming.
USING VISCA
PROTOCOL
Computer is called controller, camera is called
peripheral device.
Parameters(speed=9600 bps, data bits=8, start
bit=1, stop bit=1, no parity, MSB first).
Uses MS Comm control in Visual Basic for
transmission of commands through serial port.
Takes control of the camera by sending two
commands.
1. Address command
2. IF_CLEAR command
CAMERA CONTROL
SIGNALS(ZOOMING)
1.
2.
3.
4.
5.
6.
7.
8.
9.
Idle
Zoom in
Zoom out
Stop zoom
Full zoom in
Full zoom out
Zoom in speed(0 to 7)
Zoom out speed(0 to 7)
Digital zoom(ON or OFF)
THE PROTOCOL
Protocol conforms to GPS NMEA 0183 code.
1 2 3 4 5 6
$CMUAV,X,X,X,X,X,X
1) TILT (0=Zero, 1=Horizon, 2=Up, 3=Down,
4=Stay).
2) PAN (0=Zero, 1=Horizon, 2=Left, 3=Right,
4=Stay).
3) ZOOMING (0=Idle, 1=Zoom Out, 2=Zoom In,
3=Stop Zoom, 4=Full Zoom In, 5=Full Zoom Out).
THE PROTOCOL(Cont.)
4) ZOOM IN SPEED (0 to 7).
5) ZOOM OUT (0 to 7).
6) DIGITAL ZOOM(0=On, 1= Off).
JOYSTICK AND
KEYBOARD
Visual Basic have been used for
programming.
DLLs(Dynamic Link Libraries) of Windows
API have been used for both joystick and
keyboard programming.
1. A DLL is a library of functions that your
program can link with dynamically.
2. We only need to know how to use a
DLL and what functions it provides.
JOYSTICK AND
KEYBOARD(Contd.)
Joystick uses winmm.dll (Windows
Multimedia Dynamic Link Library). It gives
status of the joystick and its current state.
Keyboard uses user32.dll (Library for user
interface routines). It is used to find the
current state of the keyboard as which key
is pressed.
CAMERA CONTROL
Joystick input has the priority over the
keyboard.
Application can run with using only
keyboard.
Application will continue even joystick gets
disconnected.
TARGET COORDINATE
CALCULATION
Target coordinates have been calculated using
these steps.
GPS gives the coordinates (latitude and
longitude) of starting position.
Net azimuth is calculated by summing
azimuth of the UAV and pan angle (angle
made with nose of UAV).
Altitude above ground level is calculated by
subtracting local height from AMSL(GPS).
Contd.
Distance from the starting position is
calculated using AGL and tilt angle.
Distance is converted into angle made at
center of the earth.
From the starting position, azimuth and
distance angle the target coordinates are
calculated.
Algorithm has been derived from Mapping
Toolbox of MATLAB and calculation from
Visual Basic and MATLAB matches.
USING LAN
1. Winsock control from Visual Basic has
2.
3.
4.
5.
been used.
Camera station acts as a client.
Control Station acts as a server and it must
be available before the start of the
application.
Camera station sends the camera control
signals to the control station.
It receives GPS data and camera position
information from the control station.
VIDEO
1. It uses ezvidcap control to grab and
display video.
2. It just grab the video available in video
grabber card and displays it.
ACHIEVEMENTS
Generated control signals using keyboard
and joystick.
Ground based test of zooming properties of
the camera.
Displayed the video captured along with its
approximate coordinates.
RECOMENDATIONS
1. If laser altimeter is installed in direction of
the camera, the coordinates calculated will
be more accurate.
2. Course on Window based programming
should be introduced.
3. Internet should be available during project
phase.
Questions