THE EXPERIMENTS AND PERFORMANCE ANALYZES OF THE
TRACKER ROBOTS IN DIFFERENT LIGHTING
ENVIRONMENTS
S.M.Fatih APAYDIN1, Abdullah ÇAVUŞOĞLU2, Lami KAYA2
1
Distance Education Application and Research Center
Karabük University
fatihapaydin@karabuk.edu.tr
2
Faculty of Engineering and Natural Sciences
Yıldırım Beyazıt University
abdullah.cavusoglu@ybu.edu.tr, lamikaya@ybu.edu.tr
Abstract
In this study, a leader robot and tracker robot was studied on two robots. In accordance with the intended target has
been tracking the leader robot to tracker robot. Experiments were carried out in terms of performance of different soils
and environments to robots and the results of these experiments performed by measuring the necessary improvements.
Keywords: Mobile robot, remote and autonomous control, infra-red sensors, arduino.
I.
INTRODUCTION
The robots have a very important place with
respect to facilitating our lives, in the age of information
and knowledge which the technology have been
developing rapidly and this development has been
spreading quickly to all strata of society; such that
humans request many routine works in their lives being
done automatically. The technology forces its limits
insomuch that robots in appearance of human were
produced by scientists and researchers and even
autonomous mobile robot devices that can go to the
desired targets by itself have been revealed.
Concerning to mobile robot systems’ design;
such subjects have been involved like how it represents
the information related with the environment around
itself, how it learns the tasks to be carried out, what kind
of planning and problem solving to be done, how fast it
scan the data bank and information in order to reach the
answers, which mechanisms it uses in order to
recognize the world containing itself [1].
The robotic vehicle of Mercedes Benz,
developed by Ernst Dickmans and his team who had
been working at University of Bundeswehr in Munich in
1980s, achieved to reach 100 km/s speed in a road
without any traffic. Also the DARPA project, which
utilizes laser and image processing technologies and
moving with 30 km/s speed, has been developed in
1980s.
However
nowadays
General
Motors,
Volkswagen, Audi, BMW, Volvo, Google have begun
the tests of their autonomous vehicles. The General
Motors company stated that their autonomous vehicles
will start to test in the year of 2015 and these vehicles
could be on the roads in the year of 2018. The law
regarding to usage of autonomous vehicles at traffic,
also with the largest support of the Google, has been
created as being first in the world in State of Nevada of
the U.S. in June 2011 [2]. The autonomous vehicle of
Google is seen on the Figure 1.
Fig 1: Autonomous Vehicle Of Google
Also the vehicle systems which follow each
other referred as Platoon is one of the subjects that has
being studied over it recently. The platoon systems are
increasing of the usage capacities of the roads by
moving as grouping the vehicles. The platoon systems
are a technology being recommended for Automatic
Highway Systems [3]. The platoon systems aim to
shorten follow-up distance between the vehicles by
utilizing electronic and mechanic parts. Additionally
the vehicles speed up and slow down simultaneously
[4]. The California PATH Platoon sample was given in
Figure 2.
Fig 4: Mobile Robot System
III.
Fig 2: The California PATH Platoon
However some studies upon Platoon systems
known as SARTRE (Safe Road Trains for the
Environment) have been carried out in the Europe. In
scope of the project supported by European
Commission and Volvo too, it has been aimed to
develop a secure and environmentally friendly new
driving system by creating Road Trains [5]. SARTRE
Platoon sample was given in Figure 3.
APPLICATION
In this chapter, mechanical designs of
autonomous moving mobile robots as well being the
subject of this study too together with electronic
circuits and software used in order to control the robots
are described. The study is basically divided into two
areas in line with two different targets. Therefore two
different robots have been studied over. The first one of
them is the robot referred as “Pioneer” that can be
remote-controlled and determines the path. The other
one is the “Follower” robot which follows the pioneer
robot.
3.1. Pioneer Robot
3.1.1.
character of the robot
The pioneer robot is able to operate in two
different modes. For the first mode, it has an attribution
that can be remote-controlled and able to move freely.
The other mode is programmed as able to move
completely autonomous. General character of the robot
is to determine the path to be followed by planning the
way.
Fig 3: The SARTRE Platoon
II.
MOBILE ROBOTS
Mobile robots are the vehicles which are
equipped with motion systems for the purpose of able to
move inside of physical environments and able to affect
the environment and equipped with sensor systems for
the purpose of able to perceive the environment being
inside; have control architecture that carries out the
coordination and control of these systems upon
performing tasks requested from them [6]. The
components of mobile robot systems are described in
various sources with different point of views [1, 7].
General display of mobile robot system was given in
Figure 4.
3.1.2.
mechanical part
The wheels of the robot were positioned as to
move on five wheels on condition that two wheels at
sides, one ball-bearing wheel at front. The wheels at
right and left have geared motor system. It was created
by mounting two DC motor and other components on a
rectangular plexiglass material. The view from the
bottom of mechanic assembly of the pioneer robot was
given in the Figure 5 below.
Fig 5: The Bottom Of Mechanic Assembly Of The Pioneer
Robot
3.1.3.
electronic part
The pioneer robot has a form that will operate
with PIC. Electronic circuits of the robot consist of
three parts. These are; microcontroller and motor driver
circuit, line follow circuit and infra-red sensor circuit.
Microcontroller and Motor Driver Circuit
Many models are available for PIC
microcontrollers. However 16F877A model which is
being widely used and most developed has been
preferred for the pioneer robot. Also the L293D has
been used as a motor driver.
Line Follow Circuit
Three CNY70 contrast sensors and Schmitt
Trigger trigger have been used in line follow circuit.
3.2. Follower Robot
3.2.1.
character of the robot
The follower robot operates in an easily
manner due to required to be easy and fast. The general
character of the robot is to follow the front robot.
3.2.2.
mechanical part
The follower robot has a form that move on
three wheels and these were positioned as being one
wheel at each sides, one ball-bearing wheel at rear. The
robot was created by mounting two motors and other
components on a rectangular electronic card. The view
from the bottom of mechanic assembly of the follower
robot was given in the Figure 7.
Infra-red Sensor Circuits
There are TK19 infra-red receiver-transmitter
sensors on the pioneer robot. These are totally five as
being two of them at front, two of them at left and one
at right.
3.1.4.
Algorithm and Software
The software of the pioneer robot was written
in Jal programming language. The Jal is a pascal-like
and free PIC programming language. Totally 11
procedures were used in the pioneer robot. These may
be called as small code blocks inside of the software.
The algorithm of the pioneer robot can be viewed in
Figure 6.
Fig 7: The Bottom Of Mechanic Assembly Of The
Follower Robot
3.2.3.
electronic part
Electronic circuits of the robot consist of two
parts: arduiono card and sensor circuit. The follower
robot was designed as to operate with ATMEL.
ATmega8A model of ATMEL microcontroller was
used in this robot.
Arduino Circuit
Arduino card is an electronic card especially
used in many robot projects abroad and developed with
ATMEL microcontroller architecture. It can easily
develop very sophisticated robotic projects thanks to its
flexible architecture and possession of circuit elements
on itself.
Sensor Circuit
There are eight IR sensors and four LEDs on
the follower robot. The sensor circuit of the follower
robot is given in Figure 8.
Fig 6: The Algorithm Of The Pioneer Robot
Fig 8: The Sensor Circuit Of The Follower Robot
3.2.4.
algorithm and the software
The software was written in C programming
language due to usage of Arduino card in the follower
robot. The follower robot consists of totally 4 functions.
Two of them are own functions of Arduino, while the
other two are code blocks written subsequently. The
algorithm of the follower robot can be seen in Figure 9.
Fig 9: The Algorithm Of The Follower Robot
IV.
RESULTS AND EVALUATION
In this study, two robots were used as pioneer
robot and follower robot. It was achieved that the
follower robot follows the pioneer robot in line with
aimed targets. Some experiments were carried out to
the robots in terms of performance in different
environments, the results of them measured and
necessary improvement were done. These experiments
and their results are evaluated below. These experiment
results are given in list on Table 1.
Table 1: Light Testing
Light Testing Type
Daylight Environment
Energy Saving Light Bulb Environment
Dark Environment
Performance
%70
%40
%0
Some parameters have great importance in this
established system. These are ground friction
coefficient, rotation angle of the robots, light amount
that influence the robots and follow-up distance
interval. When the parameters evaluated, it was
understood that the most proper values for the
established system had occurred in feathered ground, at
daylight and turning within the interval of 0 degrees
and 30 degrees. The following distance under these
conditions were measured as averagely 7 cm. While it
was understood that the most adverse conditions for the
established system had occurred in woolen ground, at
dark and sharp turns larger than 90 degrees. Under
these conditions as well as the robots can’t follow each
other; also it was observed that difficulties had been
experienced in their movements due to high coefficient
of ground friction.
Upon examining the parameters in detail, it
was seen that while coefficient of ground friction
increases the pioneer robot slows down and
consequently the following become easier too.
However upon coefficient of ground friction rises
above the optimum values, movements of the robots
become more difficult and it emerged that heat of the
circuits had excessively increased. Furthermore it
should be noted that while coefficient of ground friction
increases, follow-up distance decreases. The rotating
angle which is another parameter is an important value
for the tracking of follower robot. Another parameter is
related with light value. While this value decreases
operating of the robots become more difficult and even
they stop. Increasing of the light value draws the
follow-up distance closer to optimum. But the most
important case here is the light reflectance of the
ground. The light reflected from the ground makes it
more difficult to follow.
V.
REFERENCES
[1] Murphy, R. R., “Introduction to AI Robotics”, MIT
Press, London (2000).
[2] İnternet:
Wikipedia
“Autonomous
Car”
http://en.wikipedia.org/wiki/Autonomous_car
(2013).
[3] Zabat, M., Stabile N., Frascaroli, S., Browand, F.,
“The Aerodynamic Performance of Platoons: Final
Report”, California PATH Research Report,
California (1995).
[4] İnternet: Wikipedia “Platoon (automobile)”
http://en.wikipedia.org/wiki/Platoon_(automobile)
(2013).
[5] Dávila, A., Nombela, M., “SARTRE: SAfe Road
TRains for the Environment”, Conference on
Personal Rapid Transit, London (2010).
[6] Özkan, M., “Farklı Özelliklere Sahip Gezgin Robot
Grubunun Dağıtık Kontrolü”, Doktora Tezi,
Eskişehir Osmangazi Üniversitesi Fen Bilimleri
Enstitüsü, Eskişehir (2007).
[7] Arkin, R.C., “Behavior-Based Robotics”, John
Wiley and Sons Press, England (2002).