ROBOCON 2010 Report Page 1
CONTENTS
Acknowledgement Page 2
Introduction Page 3
Team Page 4
1. ROBOCON 2010 Contest Page 5-16
1.1. Contest Theme
1.2. Arena Specification
1.3. Game Procedure
1.4. Scoring
1.5. Robot Specification
1.6. Rules
2. Construction Page 17-30
2.1. Manual Robot
2.1.1. Structural Components
2.1.2. Assembling the Robot
2.2. Auto1
2.2.1. Structural Components
2.2.2. Assembling the Robot
2.3. Auto3
2.3.1. Structural Components
2.3.2. Assembling the Robot
3. Automation Page 31-39
3.1. Manual Robot
3.1.1. Electronic Components
3.1.2. Interfacing PS2 Controller
3.2. Auto1
3.2.1. Basic Techniques And Game Plan
3.2.2. Electronic Components
3.3. Auto3
3.3.1. Basic Techniques And Game Plan
3.3.2. Electronic Components
Gantt Chart Page 40
Expenditure Page 41
Lessons Page 42
Conclusion Page 43
Photo Gallery Page 44-45
ROBOCON 2010 Report Page 2
ACKNOWLEDGEMENT
First of all, on the behalf of Team Robocon, we, the team members of Robocon
2010, wish to extend our heartfelt gratitude to the college authority, especially Prof. S
Bhattacharya, Director of National Institute of Technology, Durgapur, India and Prof.
A.K. Mitra, Dean (Administration) for their complete administrative support. It is our
privilege to express our sincere regards to our External Advisor, Prof. S.K. Saha, Indian
Institute of Technology, Delhi, India for his continuous guidance, encouragement and
motivation. We deeply express our sincere thanks to our Faculty-in-charge, Mr.
Aniruddha Chandra and Prof. S.K. Datta for their consistent support, whole-hearted
cooperation and constructive criticism throughout. We are greatly indebted to them for
helping us getting funds for purchasing the components required for fabricating the
robots. We would like to take this opportunity to acknowledge the support and
encouragement of Mr. Kundu, Mr. G. Datta and the entire staff at the Workshop
department; we are very grateful to them for providing us with their valuable inputs,
speedy actions in building the robots. Moreover, we express our gratitude to our
librarian Dr. M Mondal for allowing us to work in the seminar hall of the library.
Finally, we take this opportunity to thank everyone who has directly or indirectly
contributed to ROBOCON. We pay our love and respect to NIT Durgapur and its entire
family.
ROBOCON 2010 Report Page 3
INTRODUCTION
ROBOCON, short for Robotic Contest, is an interesting game-cum-intellectual exercise for budding engineers and Robotics enthusiasts. The concept of Robocon is a technically challenging event to realize the importance of originality and innovation. The event brings those future engineers the joy of realizing unique ideas and the excitement of creation. Participation in it is an end-to-end competitive experience from concept design of a system of robots programmed to perform according to rules of the game played on a precisely created challenging field and to score a victory beating the competitors; the ultimate rush of thrill and excitement for young engineers. The Asia-Pacific Robot Contest (ABU Robocon) is an Asian Oceanian College Robotic competition founded in 2002 by Asia-Pacific Broadcasting Union. In the competition robots compete to complete a task within a set period of time. The contest aims to create friendship among young people with similar interests who will lead their countries in the 21st Century, as well as help advance engineering and broadcasting technologies in the region. ABU Robocon 2010 is hosted by Egypt at Cairo scheduled on 21st September 2010.
ROBOCON 2010 Report Page 4
Team
External Advisor: Prof. S. K. Saha, Professor, IIT Delhi
Internal Advisor: Prof. S. K. Datta, Professor, ECE Department, NIT Durgapur
Mr. A. Chandra, Lectrurer, ECE Department, NIT Durgapur
Team Coordinator: Naushad Rahman
Construction Team:
1. Aniket Pateil
2. Abhishek Agarwal
3. Debarun Das
4. Debesh Pradhan
5. Niraj Chaurasia
6. Debal Saha
7. Aman Agarwal
8. Pradeep Jain
9. Amrit Pal Singh Bhinder
10. K. Ashoke Raman
11. G. Manjunath Srivastava
12. Umangaraj Aryal
13. Nirjhar Debnath
Automation Team:
14. L S Bharadwaj
15. Naushad Rahman
16. Yudhir Bhattarai
17. Prakash Agarwal
18. Manoj Kumar Yadav
19. Sunil Das
20. Amit Sahani
21. Akshay Mysore
22. Subarno Banerjee
23. Amit Srivastav
24. Praveen Sagar
25. Atikant Singh
ROBOCON 2010 Report Page 5
1. ROBOCON 2010 Contest
1.1. CONTEST THEME
Robo-Pharaohs Build Pyramids is the main theme of Robocon 2010. The Pyramids of Giza and other
monuments on the Giza Plateau are among the great world treasures. In fact, the Pyramids are the icons of
world heritage in general and are widely pictured as such. And it was these pyramids, which represented the
main theme of ROBOCON 2010. The construction of three Pyramids of Khufu, Khafraa and Mankaura, the
private tombs of the Pharos of the 4th
dynasty of Egypt, was modeled in the competition. These three
pyramids are built in a diagonal manner with the help of cubical blocks.
Figure 1.1: Virtual Image of the Giza Pyramids Site
Figure 1.2: Giza Pyramids Positioning
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Robo-Pharaohs Build Pyramids is the main theme of this contest. The idea is based on a virtual time
machine that takes ancient Egyptian Great-Pyramids builders inside classrooms of technical schools. The
new target is to build parts of the three Pyramids in sequence. Competing team members should be accurate,
fast and cooperative. They should adhere to the main requirement of not using binding material between
blocks. The winner team is the "Robo-Pharaoh" which succeeds to finish building assigned parts of the three
Pyramids first. During three minutes, red and blue teams compete in order to mimic one of the surviving
Seven World Wonders.
1.2. ARENA SPECIFICATION
The game field consists of two Automatic Zones and a Manual Zone and three Pyramids (Khufu,
Khafraa and Mankaura).
Automatic Zone #1 is the area surrounding Khafraa Pyramid.
Automatic Zone #2 is the area surrounding Mankaura Pyramid.
Figure 1.3: Game Field General View Structure and Specifications
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Figure 1.4: Game Field Detailed Dimensions
The shape and dimensions of the game field are shown in Figure 4. A wooden fence of 100 mm
height and 30 mm wide surrounds Automatic Zone #1, Automatic Zone #2, and Manual Zones.
However, the width of the fence, marked F and G, is 140 mm.
White lines are drawn on the floor of the game field. These white lines are drawn 500 mm center to
center, from the center of Khafraa Pyramid and Mankaura Pyramid respectively as shown in Figure
3. Each white line is 50mm wide.
Automatic Zones
The Automatic Zones are divided into two exclusive plateaus. Each plateau is divided into
twosections, one for the red team and the other for the blue team. A wooden fence, of 100 mm
height and 30 mm wide, separates the two sections.
The Automatic Zones (1st Plateau: Khufu and Khafraa Pyramids) contain four Start Zones and two
Stock Zones for the automatic units; namely (RA1, RA2, SRA1/2) for the red team and (BA1,
BA2,SBA1/2) for the blue team.
The Automatic Zones (2nd Plateau: Mankaura Pyramid) contains two Start Zones and two Stock
Zones for the automatic units: (RA3, SRA3) for the red team and (BA3, SBA3) for the blue team.
Each team is free to decide how to arrange the blocks in its stock zones.
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(i)Start Zones;
The dimensions of the Start Zones are shown in Figure 1.4.
The floor surface is red with RGB (255, 0, 0) for the red team and blue RGB (0, 0, 255) for the blue
team.
The floor surface of the start zone is considered as part of automatic zones.
(ii)Stock Zones;
The dimensions of the Stock Zones are shown in Figure 1.4.
The floor surface is red with RGB (255, 0, 0) for the red team and blue RGB (0, 0, 255) for the blue
team.
The floor surface of the stock zones is considered as part of automatic zones.
The stock zones has respectively for each team:
(seven+2=9) blocks for Khafraa
(one+1=2) blocks for Mankaura
(one top+1=2) Golden blocks for each Pyramid.
Each team decides the arrangement of the blocks left in the Stock Zone once they preload some
blocks on their robots.
Automatic Zones Colors: The field surface color is green with RGB (0, 255, 0) with white lines of
50 mm width.
Manual Zone
The field surface color has an RGB (255,192,192) for the red team and has an RGB (192,192, 255)
for the blue team
(i)Start Zones;
The Start Zone and its dimensions are shown in Figure 1.3 and Figure 1.4.
The colors of the Starting Area are red with RGB (255, 0, 0) for the red team and blue with RGB (0,
0, 255) for the blue team.
(ii) Stock Zones;
There are two manual stock zones, one for each team.
Each stock zone has (seven+2=9) blocks and (one top +1=2) golden blocks.
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Figure 1.5: Competition Game Field
Specifications of the Pyramids Blocks
Organizers provided samples of prefixed Pyramids' blocks whose specifications are given in Figure
1.6 with RGB (255, 210, 110) of all sides.
Figure 1.6: Specifications of Fixed Blocks
Guidance rigid bars of 18 mm diameter are fixed in the base with the appropriate heights (300 mm,
600 mm, and 900 mm). The blocks are assembled through the holes in these bars.
Organizer fixed the required axe for the Top Golden block on top of all prefixed blocks. Its
specifications are given in Figure 1.7. The bottom plate of the guidance pin (2 mm Thickness) may
be of steel and can be welded and/or glued to the prefixed blocks.
ROBOCON 2010 Report Page 10
Figure 1.7: Specifications of the Bottom Plate of the Golden Block
Organizers prepared necessary building blocks to be used by the robots with the specifications given
in Figure 1.8.
.
Figure 1.8: Specifications of Main Block
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The Top Golden block was provided by the organizer (Figure 1.9).
Figure 1.9: Specifications of Golden Block
All blocks are similar in dimensions and weight.
The blocks are made of foam polystyrene. Each block weighs 750 gm approximately. The organizer
shall provide a sample of the building block.
1.3. GAME PROCEDURE
(i) Duration of a match
Each match lasts 3 minutes.
In the following cases, a match ends even before the passage of 3 minutes.
When the task is achieved.
In the event of disqualification.
When the referees judge that continuation of the match is impossible.
(ii)Match division
Each match is divided into three phases.
A manual unit can be preloaded (before game start) with 4 blocks at maximum.
An automatic unit can be preloaded (before game start) with any arbitrary number of blocks.
Each phase is dedicated to build a Pyramid.
ROBOCON 2010 Report Page 12
Only one manual unit should be used.
The number of automatic units should be one to three units.
The first phase is to build parts in Khufu Pyramid by the Manual Robot only. The second phase is to
build parts in Khafraa Pyramid by one or two Automatic Robots. The third phase is to build parts in
Mankaura Pyramid by one Automatic Robot. The following Table shows the three phases and
assigned durations.
Phase 1
Phase 2
Phase 3
Pyramid Khufu Khafraa Mankaura
Duration (Seconds) 90 60 30
(iii)Setting of robots
Two minutes are provided for setting of all robots before the start of each match. This includes
preloading and arranging blocks in the stock zone.
Three members of each team may engage in setting of robots.
A team who fails to complete setting of robots in two minutes shall be able to resume the setting
work once the match has begun.
(iv) During a Match
One team member is responsible of starting and operating the Manual Robot.
The operator of the Manual Robot should move freely in the Manual Area with a controller in the
hands during building Khufu.
The operator of the Manual Robot should leave the Game Area after turning-off and parking the
Manual Robot anywhere in the Manual zone.
If two Automatic Robots are used (For Khafraa construction), they should be started manually at or
after the assigned start timing to build Khafraa (the Second Pyramid).
If two Automatic Robots are used (For Khafraa construction), they should power-off manually at or
slightly after the ending beep.
After switching the robot on, the team member who performs the starting operation shall
immediately leave the Game Field.
The Automatic Robot, that builds Mankaura Pyramid, can be loaded and started manually or
autonomously.
Correct positioning of blocks (see Figure 1.10) in different layers was judged by the referees
according to the following:
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Figure 1.10: Prefixed Blocks and Complete Pyramids
For all layers, the maximum allowable tolerance was 25 mm in the horizontal plane. No tolerance
was allowed in any other plane.
For a normal block: in case of exceeding the maximum allowable tolerance, no points would have
been given.
For the Top Golden Block: in case of exceeding the maximum allowable tolerance, only 50% of its
assigned points would have been given.
No points would have been given to any non-horizontal block, including the Top Golden Block.
(v) Retries of Robots
In the case of faulty Automatic Robot movements, it was possible to start again (Retry) with the
referees permission.
Team members are permitted to move a Robot to its start zone while preparing for a Retry.
It is not permitted to load an Automatic Robot with any new blocks.
At the time of the Retry, team members shall switch the robot on to start it. After switching the
robot on, the team member who performs the starting operation shall immediately leave the Game
Field.
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Retries can be made as many times as necessary.
Strategies premised on the use of Retries are banned.
1.4. SCORING
The team who places the three Golden Top Blocks of the three Pyramids in the correct directions
first is the winner. This terminates immediately the game if all blocks are in their correct positions
and/or within the allowed tolerance. This typical winner will be declared as Robo-Pharaoh (Figure
12).
If neither team has placed the three Golden Top Blocks of the three Pyramids at the end of the 3
minutes match, the winner shall be whoever has more points than the other according to the
following:
Khufu Pyramid (22 points)
1 point for a block in the 1st middle layer.
2 points for a block in the 2nd middle layer.
3 points for a block in the 3rd middle layer.
10 points for the Golden Top Block.
Khafraa Pyramid (44 points)
2 points for a block in the 1st middle layer.
4 points for a block in the 2nd middle layer.
6 points for a block in the 3rd middle layer.
20 points for the Golden Top Block.
Mankaura Pyramid (12 points)
2 points for a block in the middle layer.
10 points for the Golden Top Block.
The match result will be announced at the end of the 3 minutes as follows:
The total number of points (score) gained by each team will be announced after deduction
of any violation acts.
The team declared "Robo-Pharaoh" will be attributed 30 points over i.e. of a maximum
score of`108 points.
The winner is the team having the higher score.
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1.5. ROBOT SPECIFICATION
Each team should use one Manual Robot and 1 to 3 Automatic Robots.
The robots must not be divided into sub-units.
Communication between the Automatic Robots is allowed.
The robots used in the contest must be made by students of the university.
(i)Automatic Robots
The Automatic Robots shall move automatically once it has been started within one phase.
At the beginning of the game, in the start zone, the dimensions of the Automatic Robot including the
preloaded blocks should not exceed 1,000 mm (long) x 1,000 mm (wide) x 1,500 mm (height).There
was no size limitation after starting the game.
(ii)Manual Robot
The Manual Robot can be operated by means of a cable connection or by remote control using
infrared, visible rays or sound waves. Wireless radio control was not permitted. The operator was
not permitted to ride on the Manual Robot.
In the case of cable operation, the cable connecting the Manual Robot and the controller should be at
least 1,000 mm and not more than 3,000 mm long. The cable should be connected to the robot at
aheight of not less than 1,000 mm above the floor surface of the Field.
The dimensions of the Manual Robot was not allowed to exceed 1,000 mm (long) x 1,000 mm
(wide) x 1,500 mm (height) in the start zone. A robot should be capable of stretching its arms and
other parts within the range delimited by a circle that is 2,000 mm in diameter as viewed from
above.
(iii)Weight of the robots
The combined weight of all of a team’s robots and other devices to be used in the entire contest,
including the power source, cables, controllers, and other equipment, should not exceed 50 kg. The
weight of back-up batteries of the same type, weight and voltage as the primary batteries was,
however, exempted from this rule.
(iv)Power sources for the robots
Each team must prepare the power sources for the robots.
The voltage of the power source used by each robot should not exceed DC24V.
Any power source deemed dangerous or inappropriate by the organizer may not be used.
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(v)Detailed rules of safety
The use of explosives, fire and dangerous chemicals was prohibited.
If a laser was used, it shall be of Class 2 or less. In designing and preparing the laser, full care must
be taken to protect all persons at the venue from harm during all procedures. In particular, the
beams must be so oriented that they cannot shine into the eyes of the spectators.
Participating robots was checked and tested, according to the ROBOCON 2010 rule book, the day
before the contest. They were checked again before starting the matches. Passing this check test was
a necessary condition to allow the robot to participate in the contest. In the other case, the robot was
not allowed to participate in the contest.
1.6 RULES
(i) Violations
If a violation occurs, two points would have been deducted as a result of such violation. The following cases
were considered violations:
Intentional obstruction over the top plate was not permitted.
Any part of either the robot or its operator enters onto the zone of the opposing team or into the
space above it except while placing the Gold Top Block.
Manual Robot should not enter the Automatic Zone and the space above it except while placing
blocks on the Khufu Pyramid.
Other actions that infringe on the rules without producing disqualification.
(ii) Disqualification
A team could be disqualified if it committed any of the following during the match:
The team damages or tries to damage the Game Field, and/or facilities and equipment of opponent’s
robots.
Either the teams' robots or their operators crossed the outer boundary of their Game Field on ground
or in air.
The team had made a false start twice in the same match.
The team performs any act that was not in the spirit of fair play.
The team fails to obey instructions and/or warnings issued by the referees.
Three violations were considered as disqualifications
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2. CONSTRUCTION
2.1. MANUAL ROBOT
2.1.1 Structural Components The manual robot made by the Team ROBOCON, NIT Durgapur can be divide into 4 basic sub-assemblies:
1) Cage Sub-assembly
2) Base Sub-assembly
3) Arms Sub-assembly
4) Accessories
CAGE SUB-ASSEMBLY The Cage was made using L-shaped Aluminium Sections. One section was 40cm long and the other 145cm
Figure 2.1.1
long. There were Four sections of each type and all were joined with Screws and nuts as shown below, to
create a cage like structure a shown above.
ROBOCON 2010 Report Page 18
Figure 2.1.2
Pulleys were mounted on the cage to enable the arm sub-assembly to move in Vertical direction.
Figure 2.1.3 Figure 2.1.4
The pulley is shown in Figure 2.1.3. And their mounting on the cage is shown in Figure 2.1.4.
ROBOCON 2010 Report Page 19
BASE SUB-ASSEMBLY The base was made of Iron metal and was of dimension 90cm*90cm*25cm. It had mounting for four
driving motors which were then fixed with wheels as shown in Figure 2.1.6.
Figure 2.1.5 Figure 2.1.6
A High torque motor of 20 kgf was fixed to the base to drive the pulley system.
Figure 2.1.7
Sections were fixed on the base to mount the cage on the structure as shown.
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Figure 2.1.8
ARM SUB-ASSEMBLY The arm sub-assembly consisted of a base and two arms , with each arm containing a high torque(20 kgf)
motor at its end (Figure 2.1.9).
Figure 2.1.9
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Then each motor was fixed with a rod. The left rod was 40cm long where as the right rod was 80 cm
long(Figure 2.1.10).
Figure 2.1.10
The left arm was provided with a slider(Figure 2.1.11) and a rack and pinion arrangement (Figure 2.1.14).
Figure 2.1.11(a) Figure 2.1.11(b) Figure 2.1.11(c)
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The rack and pinion when fixed with a 10 rpm (Figure 2.1.13) motor enabled the left arm to move along a
normal line joining the two high Torque motors.
Figure 2.1.12
Figure 2.1.13 Figure 2.1.14
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ACCESSORIES
The accessories include the screws, nuts, rivets and fasteners used for making the joints.
Figure 2.1.15 Figure 2.1.16
Mainly three types of motors were used. The driving motors were encoder motors of 200 rpm (Figure
2.1.17). The high torque motors of 20kgf (Figure 2.1.18) were used for lofting the arm sub-assembly and for
actuating the rods connected to the arms. The 10 rpm motors(Figure 2.1.13) actuated the rack and pinion
arrangement.
Figure 2.1.17 Figure 2.1.18(b)
Figure 2.1.18(b)
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There was a pulley system which enabled vertical motion of the arm sub assembly inside the cage.
Figure 2.1.19 Figure 2.1.20(b)
Figure 2.1.19 represent the pulleys attached to the cage top and Figure 2.1.20 represent the pulley attached
to the high torque motor mounted on the base which actuated the whole pulley system.
The electric circuitry and the Sony Play Station 2 Controller(Figure 2.1.21) (used as controller of the manual
robot) also are considered accessories but there details are not mentioned here.
Figure 2.1.21
Figure 2.1.20(b)
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2.1.2 Assembling the Robot
Figure 2.1.22
Figure 2.1.23
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AUTONOMOUS ROBOTS
2.2. AUTO1
2.2.1 Structural Components The Autonomous robot AUTO1 can be divide into 3 basic sub-assemblies:
1) Platform Sub-assembly
2) Base Sub-assembly
3) Accessories
BASE SUB-ASSEMBLY The base frame was made up of aluminium L sections (1.5” X1.5”), riveted together.
Figure 2.2.1: Base
PLATFORM SUB-ASSEMBLY
AUTO1 robot had to build pyramid having 4 layers. Our strategy was to push blocks over the rolling
platforms and to place the blocks.
Platforms were made up of aluminium L section (1.5”X1”) and channels riveted together
o Chain drive was used in platforms to unload the blocks.
o Thrust bearings were used for rotational degree of freedom of the rotating pipes at the front of each
platform.
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o Telescopic channels were used to move the platform linearly for proper positioning of blocks.
o The platforms were supported by heavy aluminium sections attached to the base.
Figure 2.2.2: Lower platform
Figure 2.2.3: Middle platform
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Figure 2.2.4: Upper Platform
2.2.2 Assembling the Robot After assembling the structure, robot looked like as below.
Figure 2.2.5
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Figure 2.2.6
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2.3. AUTO3
2.3.1 Structural Components The Autonomous robot AUTO3 can be divide into 3 basic sub-assemblies:
1) Base Sub-assembly
2) Forebar Mechanism
3) Accessories
BASE SUB-ASSEMBLY
The base frame was made up of aluminium L sections (1.5” X1.5”), riveted together.
A bidirectional chain drive mechanism was fitted in the middle section of the base for placing the square
block in the first layer.
FOREBAR MECHANISM
The Forebar mechanism was implemented for placing the golden block on the top layer.
The forebar was made up of aluminium U and □ sections.
It was mounted on the base frame by an aluminium star section.
It was spring loaded and thus retained its initial lowered position by spring action.
2.3.2 Assembling the Robot
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3. AUTOMATION
3.1 Manual Robot
The Manual robot was semi-autonomous. It was
controlled by a human operator and was autonomous in
speed control of driving motors. The operator controlled
the robot through a standard PS2 Gamepad interfaced to
an Atmega16 microcontroller.
3.1.1 Electronic Components Used in Manual Robot :-
1. PS2 Gamepad i. It’s easy to interface with MCUs.
ii. It facilitates more decisive functions using key combinations.
iii. The Analog stick is easy to use and provides better maneuverability.
2. Atmega32 AVR series microcontroller
i. Advanced RISC architecture.
ii. Fast Performance. Up to 16 MIPS throughput.
iii. Integrated peripherals like ADC and PWM channels. ADC is required for
joystick control. The programmable PWM channel can be used to run the
driving motors directly.
iv. Less programming overhead.
3. Hercules 16V, 30Amp Motor Driver
i. Operating voltage: 6V to 36V
ii. Output current 30A peak(15Amp nominal)
iii. PWM operations up to 20 KHz
iv. Current Sense output
v. Over voltage and under voltage shutdown
vi. Thermal shutdown
vii. Protection against loss of GND and Vcc.
viii. MOSFET based reverse polarity protection
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3.1.2 Interfacing PS2 Gamepad
The PS2 console gamepad has 9 wires- 5 communication lines, VCC,
GND, vibration motor power, and a reserved line for future use.
PS2 Socket
Pin Color Name Description
1 Brown DATA Data: This is the signal from controller to host. It is an 8-bit serial transmission synchronous to
the falling edge of the clock.
2 Orange CMD Command: This is the signal from the host to the controller. Again, it is an 8-bit serial
transmission on the falling edge of the clock.
3 Grey 7.6V Vibration Motors Power: 6-9V.
4 Black GND Ground
5 Red VCC Variable power from 5 V down to 3V.
6 Yellow ATT Attention: This signal is used to get the attention of the controller. This signal will go low for the
duration of a transmission.
7 Blue CLK Clock: 500kH/z. The communication appears to be SPI bus.
8 White NC Not Connected. Reserved for future use.
9 Green ACK Acknowledge: This signal is low for at least one clock period after each 8 bits are sent and ATT is
still low.
Transmission Protocol
The PlayStation controller communicates with the host MCU via SPI protocol. All transmissions are 8-bit serial LSB
first synchronous to the falling edge of the clock. In fact, it behaves like a big shift register. So, it transmits and
receives data at the same time. That means, even to read the controller data you need to send some dummy bytes.
Command Listing:
0x42: Main polling command
This command gets all the digital and analog button states. When the host MCU wants to read controller data it
pulls the ATT line low and issues a start command (0x01). The controller will then reply with its Type ID
(0x41=Digital, 0x73=Analog). At the same time as the controller is sending this ID byte the host is transmitting get
data (0x42). Following this the CMD line goes idle and the controller transmits ready (0x5A) followed by 2 (digital
mode) or 6 bytes (analog mode) data.
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0x43: Enter / Exit Config Mode
This can poll the controller like 0x42, but if the first command byte is 0x01, it has the effect of entering config mode
(0xF3), in which the packet response can be configured.
PS2 Controller Data bytes
0x44: Switch modes between digital and analog
Only works after the controller is in config mode (0xF3).
Set analog mode: Command Byte 4 = 0x01
Set digital mode: Command Byte 4 = 0x00
If Command Byte 5 is 0x03, the controller mode is locked.
ROBOCON 2010 Report Page 34
Autonomous Robots
The problem statement for RoboCon 2010 required two pyramids (Khafraa and Mankaura)
to be built in coordination by two or three autonomous robots. We had initially built three
autonomous robots- Auto1 and Auto2 for the Khafraa pyramid and Auto3 for Mankaura
pyramid. However, due to weight and dimensional constraints, we had to replace Auto2 for
a golden block placing mechanism on Auto1.
3.2 AUTO1 (Khaafra Pyramid)
3.2.1 Basic Techniques and Game Plan
1. Grid Navigation Algorithm: The grid navigation algorithm was based on the popular PID line following algorithm
coupled with junction counting. We implemented the basic differential drive system since it’s the easiest to
implement and control with PID. We used 7 optical sensors for line following and 2 sensors were fitted on the
extreme left and right ends of the sensor panel for junction counting. Turns were timed by delays and sensor
inputs from the same sensors used for junction counting.
AUTO1 Sensor Panel
Since the direction of unloading the blocks and that of driving the base were not same, the path for Auto1 was
dependent on the allotted team or color for the match.
AUTO1 Paths
ROBOCON 2010 Report Page 35
2. Block Unload Sequence: Once the robot was
successfully navigated to its unloading position, the
block unload sequence will initiate the chain drive of
the lowest platform. Following this the robot will
have to move forward by a distance of half the grid
square in order to place the next layer in position.
This movement was synchronized by a 10th optical
sensor fitted at suitable distance from the end.
Following the unload of the middle layer, the middle
platform will slide forward to push the blocks in by
the required distance. The same will be repeated for
the top layer. We used bump sensors to detect
termination of chain drive and platform slide
processes.
AUTO1
AUTO1 Platforms
ROBOCON 2010 Report Page 36
3.2.2 Electronic Components Used in AUTO 1 :-
1. PIC18F4550: Locomotion control unit. This unit was responsible for the grid
navigation.
2. PIC16F8770: Actuation Sequence Control unit. This unit was responsible for
the actuation of chain drive systems and the sliding of the upper platforms.
3. Optical Sensors: 10 optical sensors with 12V analog output were
suitably placed for robot localization.
4. Bump Sensors: 5 bump sensors were suitably placed to detect
termination of chain drive and platform slider processes.
5. Actuation Motors:
5 12V 100 RPM DC geared motors for chain drive actuation.
2 12V 60 RPM DC geared motors for platform slider actuation.
We used CMOS motor drivers with a suitable current rating that was
sufficient to drive the actuation motors.
6. Driving Motors: 2 12V 100 RPM high torque DC motors with
quadrature incremental hall effect encoders were driven by Herculean
motor drivers to suit the high current and power rating.
7. Tap Switches: 2 tap switches for team select operation. Our game plan
had team dependent paths.
8. Power Supply: 12V 7.2 AH rechargeable Lead Acid Battery.
ROBOCON 2010 Report Page 37
Why PIC18F4550 ??
i. Pin-to-pin compatible with PIC16F8770. ii. Larger Memory Space- Flash Memory 32K, SRAM 2048 bytes EEPROM 256 bytes.
iii. USB V2.0 Compliant. iv. Four Crystal modes, including High-Precision PLL for USB. v. Integrated 10-bit, Up to 13-Channel ADC module with Programmable Acquisition Time.
vi. C Compiler Optimized Architecture with Optional Extended Instruction Set. vii. Easy availability due to commercial and industrial applications.
Why PIC16F8770 ??
i. High performance RISC CPU ii. Operating speed: 20 MHz
iii. Up to 8K x 14 FLASH Program Memory, 368 byts Data Memory (RAM), 256 bytes EEPROM iv. Upto 14 External Interrupt sources v. Selectable oscillator options
vi. Wide operating voltage range: 2.0V to 5.5V vii. Low-power consumption
viii. Integrated peripherals like 8-bit/16-bit Timer/Counter, Capture and 10-bit PWM modules ix. Easy availability due to commercial and industrial applications.
3.3 AUTO3 (Mankaura Pyramid)
3.3.1 Basic Techniques and Game Plan
1. Grid Navigation Algorithm: The Grid navigation algorithm for Auto3 was based on a timed combination of lane
and line following. The lane following was achieved by simple bang-bang line avoiding while the line following
was achieved by the PID algorithm. We used 3 optical sensors for line following and 2 sensors were fitted on the
extreme left and right ends of the sensor panel for lane following.
AUTO3 Sensor Panel
The robot was to follow the lane as shown, unload the preloaded block and return by the same lane until it
bumped with the arena back wall, then turn and lift the golden top block, follow the line and place it over the
plate. We translated the whole grid navigation through a sequence of bumps. The paths for the two teams or
colors were exactly anti-symmetric.
ROBOCON 2010 Report Page 38
AUTO3 Paths
2. Block Unload Sequence: The square block was to be unloaded by an actuated chain drive system. We
implemented an actuated forebar mechanism to lift and place the golden top block.
AUTO3 Forebar Mechanism AUTO3 Chain Mechanism
AUTO3
ROBOCON 2010 Report Page 39
3.3.2 Electronic Components Used in AUTO 3 :-
1. PIC16F8770: This controller unit was responsible for navigation &
actuation of chain drive system and the fore bar mechanism.
2. Optical Sensors: 5 optical sensors with 12V analog output were suitably
placed for robot localization.
3. Bump Sensors: 4 bump sensors were suitably placed for robot localization
and to detect termination of chain drive process.
4. Actuation Motors:
One 12V 100 RPM DC geared motors for chain drive actuation.
One 12V 60 RPM DC geared motors for fore bar mechanism.
We used CMOS motor drivers with a suitable current rating that was sufficient
to drive the actuation motors.
5. Driving Motors: 2 12V 120 RPM high torque DC motors were driven by
CMOS motor drivers to suit the high current and power rating.
6. Tap Switches: 2 tap switches for team select operation.
7. Power Supply: 12V 7.2 AH rechargeable Lead Acid Battery.
ROBOCON 2010 Report Page 40
GANTT CHART
Task Start End date Duration
SANCTION OF BUDGET AND MODELLING OF ROBOT 11/3/2009 12/18/2009 45
CONSTRUCTION OF MANUAL ROBOT 11/3/2009 12/23/2009 50
MANUAL ROBOT REMOTE 11/13/2009 12/4/2009 21
AUTONOMOUS MODELLING 12/16/2009 12/26/2009 10
CONSTRUCTION OF AUTO1 (STRUCTURE) 12/29/2009 1/8/2010 10
COMPLETION OF AUTO1 12/13/2009 1/10/2010 28
CONSTRUCTION OF AUTO3 (STRUCTURE) 12/21/2009 12/31/2009 10
COMPLETION OF AUTO3 12/31/2009 1/30/2010 30
PRACTICE AND TROUBLESHOOTING 2/3/2010 3/5/2010 30
ROBOCON 2010 Report Page 41
EXPENDITURE
Hardware
Plywood
Aluminium Sections
Chains
Racks & Pinions
Structural components
21,508.00
Electronics
Driving Motors
High Torque Motors
Motor Drivers
Sensors
MCU Boards
Accessories
154,716.41
Travel & Transport
Travel Expenses
Robot Packaging &
Transportation 22,985.00
Others
Practice Arena
ROBOCON Registration
Additional Services
27,061.00
Total 226,270.41
ROBOCON 2010 Report Page 42
LESSONS
Though the team tried to approach the problem in the most fault proof and efficient
way, there remained certain points overlooked or neglected. The team takes these as a
lesson for the future and considers a rethink.
1. Power Source: We used Lithium Ion cells as power source instead of Lead Acid
Rechargeable cells as planned. They discharged too quickly and were the primary
reason for our elimination.
2. Electronic Circuits: The interfacing circuits were all soldered by hand. They were
not very durable and 'clean'. Troubleshooting was difficult and often the circuits
behaved incorrectly. We plan to design and manufacture custom PCBs from now
on.
3. Design Issues: Though our design was stable and efficient, the construction was not
well monitored. As a result, we were forced to make last minute changes to fit to
the weight constraints. We plan for a well monitored and measured approach from
now on.
4. Transporting the Robots: We dismantled the robots completely for transporting
them to the competition venue. Though the robots were designed in such a way to
support quick dismantling and re-assembling, but it posed a huge overhead of
almost rebuilding everything and cost valuable time. We plan to transport the
complete assembled robots.
ROBOCON 2010 Report Page 43
CONCLUSION
ROBOCON sets an international platform for the robotics enthusiasts to enhance their technical skills and knowledge. Although the team's work was for the particular competition, tackling the competition specific problem undoubtedly had an impact on the overall technical knowledge. Applying the ideas and materializing the designs right from the scratch enhanced the hands-on experience of the members. Working out different approaches and analyzing the performance helped understand the actual dynamics and to build in-depth understanding. Building Robots enhanced our technical knowledge and skills as well as taught us team work and professionalism.
It's a matter of immense pride to participate in such a competition. This technical carnival was an enjoyable learning experience for the entire team. Apart from participation at the prestigious ROBOCON India, annual national level Robotic Contest, we presented our works to the public during many technical fests, seminars, meets and other events thus contributing to the overall learning process and technical awareness of the institution and other nearby colleges. The team looks forward to continue its participation in ROBOCON every year and indulge in research for better robot designs, efficient mechanisms and automation algorithms. The team also plans to share its experience and knowledge in the future through workshops, orientation programs and similar public interactions.
ROBOCON 2010 Report Page 44
PHOTO GALLERY
With Anirudhdha Chandra Sir at Team Robocon work site.
Match 1 against IIT Chennai. Defeated 3-1.
ROBOCON 2010 Report Page 45
Match 2 against IMT Ghaziabad. Won 9-0.
Team Robocon, NIT Durgapur at Balewari Indoor Stadium, site for ROBOCON INDIA 2010.