This presentation is about Lego Robotics. In this presentation, there is sufficient introduction of different sensors, motors and accessories etc.

1. Lego Robotics Workshop
Team E-Rev
e_rev14@yahoo.com
Mehran UET, Jamshoro
19-20, Sept 2016
Supervisors:
Dr. Imtiaz Hussain Kalwar
Engr. Kamran Kazi
Engr. Aamir Ali Patoli
www.facebook.com/erevmuet/

2. Schedule--Today
 Day-1
• Lecture– 10am to 12am
• Construction of Robot—12pm to 2pm
• Lunch—2pm to 3pm
• Construction Resume—3pm to 5pm

3. Contents
• What is Robotics?
• Introduction to Lego Robotics
• Lego Mindstorms EV3—3rd Generation evolution
 Intelligent Brick
 Motors
 Sensors
• Construction of Robot
• Programming
• Execution of task

4. What is Robotics?
• It is the branch of Mechanical, Electrical/Electronic and Computer
system engineering that deals with design, construction and
computer system for their control, sensory feedback and information
processing
• Mechanical Engineers are concern with design and construction
• IT Engineers are concern with control, communication and processing

5. What is Robot?
• Robot is a controllable/programmable mechanical machine.
• It can interface with humans and environment
• First robot was invented by “George Devol”

6. Industrial Robots--Gripper

7. Defence Robots

9. Contents of Robotics
• Servo Motors
• Gears
• Sensors
• Relation of Torque and Speed

11. Servo Motors
• Servo Motor: It is a simple DC motor with some circuitry.
• It contain
 DC Motor
 Gears
 Potentiometer
 Feedback Control System
• Servo Motor is used for controlled movement.
• It is used when we need specified movement. Like two rotation,
rotation for 30 sec or rotation for 90degrees

12. Mechanism of Servo Motor

13. Servo Motor—Internal components

14. Gear
• It is used to transfer
motion.
• It is used to vary
Torque and speed.
• Used to change
direction of rotating
element

15. How Motion is transferred?

16. Relation Between Torque and Speed
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1
𝑆𝑝𝑒𝑒𝑑
Torque: It tells us how much load can be drived by rotating machine
 The first gear of vehicle has more torque than speed. Due to this, you
can drive more load but at low speed.
Speed: It is angular velocity of a motor.

18. Lego Robotics

19. LEGO?

21. LEGO Group
• Lego Group has been designing different robotic kits for education
and competitive purpose

22. Lego Mindstorms EV3
• This is 3rd Generation Lego Robotic kit.
• It comes with two different package i.e. different package contain
different assortment of material
1) Retail Set 31313
2) Education Core set 45544

23. Content
• Intelligent Brick
• Motors
 Large Motors
 Medium Motors
• IR (Infrared) sensor
• Remote IR Beacon
• Ultrasonic sensor
• Color sensor
• Touch sensor

25. Intelligent Brick

26. Intelligent Brick
• Serve as control and power section for robot
• Specification
ARM9 Processor
Flash memory 16MB
Ram 64MB
Support up to four sensors and four motors
USB 2.0 communication to host PC– up to 480Mbit/sec
Support Micro SD card up to 32GB
Connectors RJ12
Power: 6 AA Batteries—1.5x6=9Volt
Wireless connection via Bluetooth and Wi-Fi

27. Motors--Large
• High Torque
• Less Speed
• Used to move robot
like tires in cars
• Running Speed: 160-
170rpm
• Running Torque:
20Ncm

28. Motors--
Medium
• Less Torque
• High Speed
• Used to move small
parts of robot. Like
Arm, lift, gun etc
• Running Speed: 240-
250rpm
• Running Torque:
8Ncm

29. Large Motor Medium Motor
More Powerful Less Powerful
Slower Faster

30. Sensor--
Ultrasonic
• It works on the
principle of reflected
sound waves
• Used to measure
distance
• One ultrasonic sensor
can detect other
ultrasonic sensor
operating nearby
• Range: 3-250cm with
+/- 1cm

31. How it works?
• Ultrasonic sensor emits sound waves. These sound waves reflect back
if there is an object in front of sensor. Ultrasonic detects these
reflected sound waves and measures the time interval between
transmitting and receiving the sound waves. By using the measured
time interval it estimates distance between sensor and object

32. How it works?

33. Sensor—
Infrared(IR)
• It works on the principle of
reflected Light waves
• Detects infrared light
reflected from object or
sent from IR remote/beacon
• Use to measure distance or
proximity
• It detects the reflected light
and estimate the distance
between sensor and object
up to 70cm(Proximity
Mode) depending upon the
shape and size of object.

34. How Infrared sensor works

35. Ultrasonic and Infrared work on
the same principle of Radar and
Sonar
• Radar produce radio waves to detect object—Used in defense mechanism
• Sonar produce sound waves to detect object– Used in Submarines

36. Ultrasonic Vs Infrared…
Which one is better?
Infrared Sensor can not work in dark
environment while Ultrasonic can.
Whereas Ultrasonic is not very good in
defining edges of area

37. Drawback of Infrared sensor

38. Ultrasonic and Bat…

39. Sensor--Color
• It is used to detect seven
different colors, reflected
light intensity and
ambient light intensity
• Ambient Light tells us how
bright or dark the
environment is.
• Cell phone has built-in
ambient light sensors. Due
to this cell phone adjusts
its brightness by itself

40. How color sensor works?
Do colors exist?

41. What is Color?
• Confused? Light, an electromagnetic wave, can come in different
wavelengths. These wavelengths enter your eye and the energy gets
absorbed by cells on the back of your eye. This light energy then gets
converted into chemical energy, gets processed by a few hundred
million specialized neurons, and after a few fractions of a second
magically your brain says wavelength 450nm is blue and wavelength
520nm is green.

42. How Color sensor works?
• The color/light sensor shines the white light on object and detects the
reflected colored light.
• The color sensor shines three colors (RGB—Red, Green and Blue) on object,
measure the reflected color intensity and recognize the actual color of
object.
 If we shine RGB on red object, the red color becomes more brighter and
reflect back with more intensity while the green and blue get absorbed by
object—Hence the sensor can detect red color
Above principle is same for green and blue color
• It can also record the intensity(brightness) of color/light.
• It has photodiode, which convert the light into current.

45. How human eye detect color?

46. Sensor--Touch
• It is like a button.
• It sense Pressed,
Released and Bumped
• Bumped=Pressed and
Released

47. Sensor--Gyro
• It sense the rotational
motion on one axis or
rate of rotational
motion(degrees per
second)—Angular
Velocity
• Measures how fast
and how far your
robot is turning

48. Application of Gyro Sensor
• Gyro sensor is used in airplane, jet plane etc
• Your cellphone has built-in Gyro sensor
 Screen rotation is sensed by Gyro sensor

49. Infrared(IR)
Beacon/Remote
• Used to control robot
• Can be used in 2 modes
• 1. Beacon ( IR sensor follows it)
• 2. Remote (sends commands to brick)

50. Accessories Education Edition Home edition
Rechargeable Battery Yes No
Intelligent Brick 1 1
IR Beacon (Infrared Remote Control) 0 1
Infrared Sensor 0 1
Ultrasonic Sensor 1 0
Touch Sensor 2 1
Color Sensor 1 1
Gyro Sensor 1 0
Large Motor 2 2
Middle Motor 1 1

52. Construction of Robot
Lets Start

53. How to construct your
Robot?
Just join/connect different components of Robot according to your
design/task

54. Here are the Components