Zack Nemes

1
Object Tracking
By Smart Lego Camera
By

• Zack Nemes

Clemence Larroche
2
Our Goal
To track and follow a car as it travels along a
path.
3
Abstract
In our portion, we built a Lego base with two
motors attached to a camera.
It rotates from side to side and up to down.
It is mounted on a platform well above the ground
and follows a yellow cylinder, which is placed
on a Lego vehicle.
4
The Hardware
Infrared communication
USB Camera
Lego Mindstorm robot invention kit

• 2 Motors

• RCX 2.0 micro controller

• Lego camera and blocks

5
The Software
Matlab
Video OCX
Visual Basic
Phantom Active X
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How???
A rotating platform was built with a Lego digital
camera attached to it.
A yellow cylinder was mounted on the car and
served as a target
The program captured images from the camera and
sent control commands to the camera according to
what it saw.
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Image Processing
An effective way of distinguishing objects is by
processing their colors
Each pixel in an image has three color
components Red, Green, and Blue.
There are other distinctive properties such as
HSV (Hue, Saturation, and Values).
Our yellow cylindrical object was found to
contain a high amount of red and low blue
compared to the color components in its
surroundings.
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Our Program
The program first tells the camera to recognize
the yellow cylinder based on its Red and Blue
properties.
It then plots a dot at the center of the object
by averaging the X and Y values of the red and
blue component pixels.
The cameras field of view is broken up into
boxes to which we attribute different vertical
and horizontal movements.
Once it locates its target in one of the boxes it
moves a specified quantity of time (here the
units are in ms - milliseconds) to center the
object.
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The boxes
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Borders
In order for the pictures to come out clear, the
object which we tracked needed to move at a very
low speed.
Sometimes it is difficult to set the object in
the center of the frame after one picture
because of the lack of precision of our timers.
The algorithm is dependant on the given
surroundings
11
Conclusion
The task of teaching robots the simplest of
tasks which humans accomplish subconsciously is
far more difficult and complex than expected.
The success of this project is limited to lab
room setting.
Even though this projects tasks were so basic,
the actual Programming and algorithms were
nonetheless confusing.