Our BTech Final Project Presentation Slide: Wireless Powered WMS Robot. A Fully Autonomous WMS Robot powered by AtMega 2560 with Artificial Intelligence.

1. EMBEDDED SYSTEMS:-
WAREHOUSE MANAGEMENT ROBOT
PROJECT GUIDE:
ANIL KUMAR KK
DEPT. OF ECE, CUSAT
PRESENTED BY:
AJAI JOHN CHEMMANAM (13130202)
ARJUN R KRISHNA (13130212)
GOKUL PRASAD (13130223)
GOKUL U S (13130224)
SHABAB P K (13130251)

2. INTRODUCTION
A ‘Warehouse Management System' (WMS) is a key part of the supply chain and
primarily aims to control the movement and storage of materials within a
warehouse and process the associated transactions, including shipping,
receiving, put away and picking. Warehouse management is an aspect of logistics
and supply chain management. More precisely, warehouse management involves
the receipt, storage and movement of goods, (normally finished goods), to
intermediate storage locations or to a final customer. In the multi-echelon model
for distribution, there may be multiple levels of warehouses. Everywhere, there
needs to be a lot of employees or workers.

3. Through this project, we are researching
and building on an autonomous robot
which does all the warehouse
management tasks and thus enabling the
industries to have
• A better and automatic warehouse
management
• Improved efficiency
• Time management
• Reduction in errors
• Reduce human work load
• Lesser human resource requirement

4. EXISTING TECHNOLOGY
Current technology involves manual machines, human labour, or even semi-
autonomous robots to do the warehouse works.
The main problem with all these existing
technologies are
*Cost *Time *Human Resources

5. AIM OF PROJECT
The main aim of this project is to build a fully
“Autonomous Robot For Warehouse Management Purposes”
For the demonstration purpose, an arena is set, which represents a typical Warehouse. In
the demonstration, we are planning to:-
 Detect the Objects correctly
 Recognize the colour of the objects
 Picking the object
 Deciding the shortest path possible
 Moving towards the appropriate destination through the shortest path
 Placing the objects
 Returning to the next pickup point
 Completing the task in the least time.

6. THE ROBOT
Thanks to the ERTS LAB (
Embedded Real Time Systems
LAB), IIT BOMBAY
Our proposed project was
approved and sponsored by
them
FIREBIRD V Robot Development
Kit was provided for developing
our project
Fi
g
4.4
:
-FIREBIRD V Bottom
View

7. FIRE BIRD V ATMEGA2560 TECHNICAL
SPECIFICATION
Microcontroller:
Atmel ATMEGA2560 as Master microcontroller (AVR architecture based
Microcontroller)
Atmel ATMEGA8 as Slave microcontroller (AVR architecture based Microcontroller)
Sensors:
 Three white line sensors (extendable to 7).
 One Sharp GP2Y0A02YK IR range sensor.
 Eight analog IR proximity sensors
 Two position encoders (extendable to four)
 Battery voltage sensing & Current Sensing

9. Indicators:
 2 x 16 Characters LCD
 Buzzer and Indicator LEDs
Control:
 Autonomous Control
 PC as Master and Robot as Slave
in wired or wireless mode
Communication:
 USB Communication
 Wired RS232 (serial)
communication
 Wireless ZigBee Communication
(XBee wireless module)
Dimensions:
 Diameter: 16cm
 Height: 8.5cm
 Weight: 1100gms

10. Power:
 9.6V Nickel Metal Hydride (NiMH)
battery pack and external Auxiliary
power from battery charger.
 On Board Battery monitoring and
intelligent battery charger.
Battery Life:
 2 Hours, while motors are
operational at 75% of time
Locomotion:
Two DC geared motors in
differential drive configuration
and caster wheel at front as
support Top Speed: 24 cm /
second
Wheel Diameter: 51mm
Position encoder: 30 pulses per
revolution
Position encoder resolution: 5.44
mm

11. GOING ON DETAIL…

12. WHAT IT LOOKS FROM DOWN ;-)

13. THE MICROCONTROLLER ADAPTER BOARD

14. “THE BRAIN” : MICROCONTROLLERS
A microcontroller is a small computer (SoC) on a single integrated circuit
containing a processor core, memory, and programmable input/output
peripherals.
Fire Bird V microcontroller adapter board has two microcontrollers.
ATMEGA2560 (master microcontroller)
ATMEGA8 (slave) microcontroller.
They communicates using a SPI bus.

15. ATMEGA 2560
• The high-performance, low-power Atmel 8-bit AVR RISC-based
microcontroller combines 256KB ISP flash memory, 8KB SRAM, 4KB EEPROM,
86 general purpose I/O lines, 32 general purpose working registers, real time
counter, six flexible timer/counters with compare modes, PWM, 4 USARTs,
byte oriented 2-wire serial interface, 16-channel 10-bit A/D converter, and a
JTAG interface for on-chip debugging. The device achieves a throughput of 16
MIPS at 16 MHz and operates between 4.5-5.5 volts.
• By executing powerful instructions
in a single clock cycle, the device
achieves a throughput approaching 1
MIPS per MHz, balancing power
consumption and processing speed.

16. ATMEGA8 SLAVE MICROCONTROLLER
• Fire Bird V robot can be
interfaced with more than 30
sensors at the same time.
• ATMEGA2560 does not have
sufficient number of ADC
available of sensor interfacing.

17. ATMEGA2560 MICROCONTROLLER

18. ROBOTIC COMMUNICATION
1. Serial Communication
• Robot has 9pin female DB9 connector
for serial communication. Out of these
9 pins only Tx (pin 3) Rx (pin 2) and
ground (pin 5) are connected to the
microcontroller via MAX202 RS232 to
serial TTL / CMOS logic converter.

19. 2. ROBOT CONTROL USING RS232 SERIAL PORT
UART1 of the ATMEGA2560 microcontroller is connected to the serial port
via MAX202 UART to RS232 converter.
ROBOTIC COMMUNICATION

20. 3. USB COMMUNICATION
Fire Bird V’s main board has USB
port socket. Microcontroller
accesses USB port via main board
socket. All its pins are connected to
the microcontroller adapter board
via main board's socket connector.
ROBOTIC COMMUNICATION

21. SENSORS
A sensor is an object whose purpose is to detect events or changes in its
environment, and then provide a corresponding output. A sensor is a type of
transducer.
Different Types of Sensors Used are:
 Sharp IR Sensors
 Infrared Proximity Sensor
 White Line Follower
 Colour Sensors

22. SHARP IR SENSORS
 Used For accurate distance measurement
 Upto 5 IR range sensors can be used
 Consists of IR LED and linear CCD array, both
encapsulated in the housing with precision lens
assembly mounted in front of them.

24. • IR LED transmits a narrow IR beam.
• Light hits the obstacle and reflects
back to the linear CCD array.
• Depending on the distance from the
obstacle, angle of the reflected light
varies.
• This angle is measured using the
CCD array to estimate distance from
the obstacle.
• Distance is function of the angle of
reflection and not on the reflected
light intensity.
HOW IT WORKS?

25. INFRARED PROXIMITY SENSORS
Used to detect proximity of any
obstacles in the short range.
Upto 10cm sensing range.
These sensors sense the presence of
the obstacles in the blind spot region
of the Sharp IR range sensors.
Fire Bird V robot has 8 IR proximity
sensors.

26. WHITE LINE SENSOR:
• Used for detecting white line on the
• ground surface.
• Used to give robot sense of localization
• Consists of a highly directional photo transistor for line sensing and bright red
LED for the illumination. Due to the directional nature of the photo diode it does
not get affected with ambient light unless it is very bright.

27. WHITE LINE SENSOR:
White Line Sensor Calibration

28. COLOUR SENSORS:
• It checks for the colour of the package.
• If the pulses value of all the colours are below the threshold
value, 1600 say, then the package is said to be of black
colour and the package is left unpicked.
• If the pulses value of red is more, then the package is of red
colour and the package is picked and placed in the
respective deposition zone.
• If the pulses value of green is more, then the package is of
green colour and the package is picked and placed in the
respective deposition zone.
• If the pulses value of blue is more, then the package is of
blue colour and the package is picked and placed in the
respective deposition zone.
• Thus, colour of the package is detected.

29. INDICATORS
Liquid Crystal Display (LCD) Indicator
LCD operates in 4 bit interfacing mode (4 Data Lines & 3 Control Lines)

30. INDICATORS
Buzzer
• A 3 KHz piezo buzzer is used.
• It can be used for debugging purpose or as attention seeker for a particular event.
• Also used for battery monitoring circuit to alert the battery low indication.
• The buzzer is connected to PC3 pin of the microcontroller. Also the same buzzer is

31. INDICATORS
Position Encoder LEDs
These LEDs are used to display the pulses coming from the left, right and C2
motor connectors.

32. INDICATORS
Bargraph LED display
It is used for quick debugging purpose. It is connected to the PORTJ of the
ATMEGA2560 microcontroller. To enable bargraph jumper J3 needs to be
connected.

33. MOTION CONTROL
• It has 75 RPM DC geared motors in differential drive configuration
along with the third caster wheel for the support.
• Robot has top speed of about 24cm per second. Using this
configuration, the robot can turn with zero turning radius by rotating
one wheel in clockwise direction and other in counter clockwise
direction. Position encoders are mounted on both the motor’s axles to
give a position feedback to the microcontroller.

34. • Motion control involves velocity and direction control.
• Motors are controlled by L293D dual motor driver (600mA of current).
• To change the direction of the motor, appropriate logic levels
(High/Low) are applied to L293D’s direction control pins.
• Velocity control is done using Pulse Width Modulation (PWM).
• LEDs are connected at the input stage of the motor driver for quick
interpretation of the motion commands

35. PULSE WIDTH MODULATION FOR
VELOCITY CONTROL
• Pulse width modulation is a process in which
duty cycle of constant frequency square wave
is modulated to control power delivered to the
load i.e. motor.
• Duty cycle is the ratio of ‘TON/ T’. Where ‘TON’ is
ON time and ‘T’ is the time period of the wave.
Power delivered to the motor is proportional to
the ‘TON’ time of the signal. In case of PWM the
motor reacts to the time average of the signal.
• PWM is used to control total amount of power
delivered to the load without power losses
which generally occur in resistive methods of
power control.

36. POSITION ENCODERS
• Position encoders give position / velocity feedback to the robot.
• It is used in closed loop to control robot’s position and velocity.
• Position encoder consists of slotted disc which rotates between optical
encoder (optical transmitter and receiver).
• When slotted disc moves in between the optical encoder we get square
wave signal whose pulse count indicates position and time period /
frequency indicates velocity.

37. • Optical encoder MOC7811 is used as position encoder on the robot.
• It consists of IR LED and the photo transistor mounted in front of each other
separated by a slot and encased in black opaque casing and facing each
other through narrow window.
• When IR light falls on the photo transistor it gets in to saturation and gives
logic 0 as the output. In absence of the IR light it gives logic 1 as output.
• A slotted encoder disc is mounted on the wheel is placed in between the slot
of MOC7811. When encoder disc rotates it cuts IR illumination alternately
because of which photo transistor gives square pulse train as output. Output
from the position encoder is cleaned using Schmitt trigger based inverter
(not gate) IC CD40106.

38. CALCULATION OF POSITION ENCODER RESOLUTION
When Robot is moving forward or backward (encoder resolution is in mm)
 Wheel diameter: 5.1cm
 Wheel circumference: 5.1cm * 3.14 = 16.014cm = 160.14mm
 Number slots on the encoder disc: 30
 Position encoder resolution: 163.2 mm / 30 = 5.44mm / pulse.

39. POWERING UP FIRE BIRD V
• It can be powered by Battery Power or Auxiliary Power
• Rechargeable 9.6V, 2.1Ah Nickel Metal Hydride battery
• The battery voltage can vary between 12V (fully charged) to 8V
(discharged). Battery pack should not be discharged below 8V (1V per cell)
for extended battery life.

40. POWER MANAGEMENT SYSTEM
It performs following functions.
• Battery voltage monitoring and Smart battery charging
• Regulated supply for on-board payload
• Battery current sensing
Power management block provides power to the microcontroller, other devices
and the power to the servo motor.
ATMEGA2560 microcontroller adapter board has two low drop voltage
regulators:
• “5V uC” supplies power to the microcontroller and its peripherals.
• “5V servo” supplies power to the servo motor.

41. ROBOTIC ARM

42. ACTUATORS USED
1. DC Motors
A DC motor is any of a class of electrical machines that converts direct current
electrical power into mechanical power.
A DC motor's speed can be controlled over a wide range, using either a variable
supply voltage or by changing the strength of current in its field windings.
When we supply power, a DC motor will start spinning until that power is
removed. Most DC motors run at a high RPM (revolutions per minute). The speed
of DC motors is controlled using pulse width modulation (PWM), a technique of
rapidly pulsing the power on and off. The percentage of time spent cycling the
on/off ratio determines the speed of the motor then the motor will spin at half the
speed of 100%. Each pulse is so rapid that the motor appears to be continuously
spinning with no stuttering.

43. ACTUATORS USED
Advantages of DC motors
1. Speed control over a wide range both above and below the rated speed
2. High starting torque
3. Accurate steep less speed with constant torque
4. Quick starting, stopping, reversing and acceleration
5. Free from harmonics, reactive power consumption
Disadvantages of DC motors
1. High initial cost
2. Increased operation and maintenance cost due to presence of commutator and
brush gear
3. Cannot operate in explosive and hazard conditions due to sparking occur at
brush ( risk in commutation failure)

44. ACTUATORS USED
Servo motors
• It is a rotary actuator or linear actuator that allows for precise control of
angular or linear position, velocity and acceleration.
• Consists of a suitable motor coupled to a sensor for position feedback.
• It also requires a relatively sophisticated controller, often a dedicated module
designed specifically for use with servomotors
• Servomechanism is a closed-loop mechanism that uses position feedback to
control its motion and final position.

45. ACTUATORS USED
Servo motors
• Servo motors are generally an assembly of four things: a DC motor, a gearing set,
a control circuit and a position-sensor (usually a potentiometer).
• Servo motors do not rotate freely like a standard DC motor. Instead the angle
of rotation is limited to 180 Degrees (or so) back and forth.
• Servo motors receive a control signal that represents an output position and
applies power to the DC motor until the shaft turns to the correct position,
determined by the position sensor.

46. ACTUATORS USED
Stepper motors
• A stepper motor is essentially a servo motor that uses a different method of
motorization.
• A servo motor uses a continuous rotation DC motor and integrated controller
circuit, where as, stepper motors utilize multiple toothed electromagnets
arranged around a central gear to define position.
• Stepper motors are available in two varieties; unipolar or bipolar. Bipolar
motors are the strongest type of stepper motor.
• The design of the stepper motor provides a constant holding torque without
the need for the motor to be powered and, provided that the motor is used
within its limits, positioning errors don’t occur, since stepper motors have
physically pre-defined stations.

47. ACTUATORS USED
Servo motor Stepper Motor
Consumes power as it rotates to the
commanded position but then it rests
It runs warm to the touch because they
continue to consume power to lock in
and hold the commanded position
Imparts High Performance Performace low compared to servo
motor
Cost is High Low Cost Compared to Servo Motor
Has the ability to control position Not so good at positioning
Considered when high performance of
importance
Considered to save cost

48. ARENA ANALYSIS
• For the demonstration purpose, we have designed an arena which
represents the simplified abstraction of a warehouse. The arena
specifications are as follows:-
• There are 12 pick-up points marked on the arena. Packages of different
types represented by blocks of colours Red, Blue, Green or Black will be
placed on these pick-up points. A pick-up point may or may not contain a
package.
• The deposition zones are indicated by 1, 2, 3, 4, and 5 in the arena. The
black line on the arena is the line along which the robot will navigate its
path.

51. WORKING MECHANISM
NAVIGATION SCHEME
• The white line sensors are used for line following mechanism
• At first, the robot senses the block present to its immediate left and places
it in one of its nearest deposition zones
• It then moves to the next nearest pick-up point and follows the above
mechanism for deposition
• The gripper is used to hold the block firmly
• The arm mechanism makes sure the block placing is within the deposition
zone

52. • If the colour sensor senses the block to be black then it just buzzers
for a second and moves to the next nearest pick-up point
• A counter is maintained for each deposition zone to note the number
of blocks deposited in it, If the blocks are 2 then no more are
deposited in it
• If there is no free deposition-sites present for a block it is left
unpicked
• IR proximity sensors are used for calculating the distance between the
bot and the block
WORKING MECHANISM
NAVIGATION SCHEME

53. • It is made the robot stops at an appropriate distance from the block
to sense the colour and pick it up using the arm
• If the deposition zone is the fifth one it moves to approximately the
nearest one from there
• A note is also made whether a pick-up site is already tested or not
• Once visited pick-up sites are not re-visited
• Continuous buzzer is blown after the completion of the task
WORKING MECHANISM
NAVIGATION SCHEME

54. CHALLENGES & FUTURE IMPROVEMENTS
Battery Life
The Robot has limited battery life. Using Solar panels can be used in case
of outdoor uses. Wireless Charging can also be a solution in future.
Proper lighting conditions for colour sensing
Currently, Colour Sensor has to be calibrated for different lighting
conditions. Placing a light source with colour sensor can rectify it to a
limit. In future, an auto colour sensor calibration mechanism have to be
made.

55. Avoiding Collision
In case of multiple robots used in the same place, a robot inter-collision
avoiding mechanism have to be designed. Integration of Swarm Robotics
(Robots communicate each other) is one of the probable solutions.
Obstacle Avoidance
If any obstacle is on the path of robot (Like a misplaced or fallen
warehouse package), A Mechanism to avoid them and to choose an
alternate path, have to be designed and built in future.
CHALLENGES & FUTURE IMPROVEMENTS

56. Power consumption by Motors
Major power consumer in the setup are the actuators used in arm and
motors for movement. We have to optimise the power consumption of such
motors, Balancing the Dc motors and power of gravity to lift and keep the
objects up. Such efficient optimisation can help the batteries to long last.
Robotic arms
The robotic arm has a limited degrees of freedom. A more complex arm, can
have a wide variety of movements in different directions. Future design of
more advanced arm mechanism can increase the speed of operation and
efficiency.
CHALLENGES & FUTURE IMPROVEMENTS

57. Navigation Techniques
Currently used Black line following is not appropriate for all purposes,
especially outside uses. Position based encoding is also a solution but it
become difficult to modify the uses and tasks. GPS enabled robots may be
used in future.
No End User Interface
At present, there isn’t any end user interface where the user can input the
details such as where the objects have to be placed. So an easier data input
method have to be designed in future.

58. FUTURE SCOPE
• Warehouse Management Purposes
• Household purposes: - For keeping the household things in appropriate places.
• Road safety purposes: - For placing traffic dividers, traffic cones in appropriate
places on road.
• For military purposes: - Depositing weapons in tactical places, Picking bombs
and detonators and disposing them are important applications of these type of
robots in military.
• For Courier Services:- A GPS enabled robot can do the courier service.
• For Newspaper Distribution:- Different Newspapers can be distributed at
different localities

59. CONCLUSION
The benefits of warehouse robotics include:-
• Improved Productivity and efficiency without adding labour
• Reduced Labour And Operational Costs
• Increased in Inventory Control and accuracy
• Enable increased order throughput
• Increase capability to meet future business requirements
• More visibility within the warehouse
• Fewer Safety Incidents
• Faster Cycle Times

60. Our proposed Warehouse Management System has the following unique
features:-
• Real-Time
• Parallel, Random Access to all locations in the warehouse
• Simultaneous Picking and Put-away
• Combination of Storage, Movement and Sortation in one Equipment
• Customizable, Modular And Flexible System
CONCLUSION

61. REFERENCES
[1] Abhimanyu Bhargava, Rohit Narula, Satish Kumar, “Autonomous Robot
Navigation of Corners with Uncertain Sensor Information,” Jun. 2008.
[2] H. Kopetz, “Automotive electronics,” in Proceedings of the 11th Euromicro
Conference on Real-Time Systems, June 1992, pp. 132–140.
[3] J. Zhou and H. Peng, “Range policy of adaptive cruise control vehicles for
improved flow stability and string stability,” in IEEE Transactions on Intelligent
Transportation Systems, vol. 6, June 2005, pp. 229–237.
[4] R. Rajamani and C. Zhu, “Semi-autonomous adaptive cruise control systems,”
IEEE Transactions on Vehicular Technology, pp. 1491–1501, Sept 2002.

62. MANUALS & JOURNALS
[1] Firebird V Robot Hardware Manual
[2] Firebird V Robot Software Manual
[3] “Resource management for real-time tasks in mobile robotics”, The Journal of
Systems and Software, November 2006
WEBSITES
[1] http://nptel.iitm.ac.in/video.php?courseId=1052
[2] http://www.nex-robotics.com/fire-bird-v.html
[3] http://www.portal.e-yantra.com
REFERENCES