SEMINAR TOPIC:

GUIDED BY: SUBMITTED TO: SUBMITTED BY:

Prof. R.S.S. Rawat Prof.

R.S.S.RAWAT

ROBOT CLASSIFICATION,WORKING

AND SPESIFIC UTILITY OF ROBOTS

CHETAN YADAV

0601ME111018

ROBOT CLASSIFICATION,WORKING AND SPESIFIC UTILITY OF ROBOTS

Robotics

Sections:

1. Introduction

2. Elements of Robots

3. Classification of Robots

4. Utility of Robot

5. Advantages

6. Disadvantages

Robot Defined

A robot is a reprogrammable,

multifunctional manipulator designed

to move material, parts, tools, or

specialized devices through variable

programmed motions for the

performance of a variety of tasks.

Working of Robot and it’s Elements

A Robot is a system, consists of the following

elements, which are integrated to form a whole:

Manipulator / Rover : This is the main body of the

Robot and consists of links, joints and structural

elements of the Robot.

End-effector : This is the part that generally

handles objects, makes connection to other

machines, or performs the required tasks.

It can vary in size and complexity from a end

effector on the space shuttle to a small gripper.

Robot Elements

Actuators : Actuators are the muscles of the manipulators. Common types of actuators are servomotors, stepper motors, pneumatic cylinders etc.

Sensors : Sensors are used to collect information about the internal state of the robot or to communicate with the outside environment. Robots are often equipped with external sensory devices such as a vision system, touch and tactile sensors etc which help to communicate with the environment

Controller : The controller receives data from the computer, controls the motions of the actuator and coordinates these motions with the sensory feedback information.

Controller

CLASSIFICATION

:

DEGREES OF

FREEDOM: ROBOT

ARM

ROBOT WRIST.

ARM

GEOMETRY:

Cylindrical

Spherical

Cylindrical

CLASSIFICATION

Spherical

CLASSIFICATION:

POWER

SOURCES:

ELECTRICAL

HYDRAULIC

INTELLLIGENCE LEVEL:

LOW

TECHNOLOGY(NONSERVO)

HIGH-TECHONOLOGY(SERVO).

SERVO

battery

RADIOIS0TOPE THERMOELECTRIC

GENERATOR

1.Preprogrammable

2 . Man controlled

3.Intelligent Robots

CLASSIFICATION:

Man controlled

Intelligent Robots

Cartesian/Rectangular Gantry(3P) :

These Robots are made of 3 Linear

joints that orient the end effector,

which are usually followed by

additional revolute joints.

CLASSIFICATION:

CLASSIFICATION:

Cylindrical (R2P): Cylindrical

coordinate Robots have 2

prismatic joints and one

revolute joint.

CLASSIFICATION:

Spherical joint (2RP): They

follow a spherical coordinate

system, which has one linear and

two rotationary coordinates.

CLASSIFICATION:

Articulated/anthropomorphic(

3R) :An articulated robot’s

joints are all revolute, similar

to a human’s arm.

CLASSIFICATION:

Selective Compliance Assembly

Robot Arm (SCARA) (2R1P): They

have two revolute joints that are

parallel and allow the Robot to

move in a horizontal plane, plus an

additional prismatic joint that

moves vertically.

Degrees of Freedom

Degrees of Freedom

refer to the

movement range

available for a

given piece of

equipment within

three dimensions.

©Emil Decker, 2009

Robot Classification:

Degrees of Freedom

Diagram courtesy: Dr. Eberhard Bamberg Assistant Professor of Mechanical Engineering University of Utah

©Emil Decker, 2009

Robot Classification:

The six degrees of a

rigid body are

often described

using nautical

terms:

Moving up and down

(heaving);

Moving left and right

(swaying); ©Emil Decker, 2009

Robot Classification:

Moving forward and

backward

(surging);

Tilting forward and

backward

(pitching);

Turning left and right

(yawing);

Tilting side to side

(rolling). ©Emil Decker, 2009

DEGREES OF FREEDOM (CONTD.)

THE THREE DEGREES OF FREEDOM LOCATED IN THE ARM OF A ROBOTIC SYSTEM ARE:

THE ROTATIONAL REVERSE: IS THE MOVEMENT OF THE ARM ASSEMBLY ABOUT A ROTARY AXIS, SUCH AS LEFT-AND-RIGHT SWIVEL OF THE ROBOT’S ARM ABOUT A BASE.

THE RADIAL TRAVERSE: IS THE EXTENSION AND RETRACTION OF THE ARM OR THE IN-AND-OUT MOTION RELATIVE TO THE BASE.

THE VERTICAL TRAVERSE: PROVIDES THE UP-AND-DOWN MOTION OF THE ARM OF THE ROBOTIC SYSTEM.

THE THREE DEGREES OF FREEDOM LOCATED IN THE WRIST, WHICH BEAR THE NAMES OF AERONAUTICAL TERMS, ARE

PITCH OR BEND: IS THE UP-AND-DOWN MOVEMENT OF THE WRIST.

YAW: IS THE RIGHT-AND-LEFT MOVEMENT OF THE WRIST.

ROLL OR SWIVEL: IS THE ROTATION OF THE HAND.

POWER SOURCES

THE FOUR POWER SOURCES USED IN CURRENT ROBOTS ARE:

ELECTRIC: ALL ROBOTS USE ELECTRICITY AS THE PRIMARY SOURCE OF ENERGY.

ELECTRICITY TURNS THE PUMPS THAT PROVIDE HYDRAULLIC AND PNEUMATIC PRESSURE.

IT ALSO POWERS THE ROBOT CONTROLLER AND ALL THE ELECTRONIC COMPONENTS AND PERIPHERAL DEVICES.

IN ALL ELECTRIC ROBOTS, THE DRIVE ACTUATORS, AS WELL AS THE CONTROLLER, ARE ELECTRICALLY POWERED.

BECAUSE ELECTRIC ROBOT DO NOT REQUIRE A HYDRAULIC POWER UNIT, THEY CONSERVE FLOOR SPACE AND DECREASE FACTORY NOISE.

NO ENERGY CONVERSION IS REQUIRED.

PNEUMATIC: THESE ARE GENERALLY FOUND IN RELATIVELY LOW-COST MANIPULATORS WITH LOW LOAD CARRYING CAPACITY.

PNEUMATIC DRIVES HAVE BEEN USED FOR MANY YEARS FOR POWERING SIMPLE STOP-TO-STOP MOTIONS.

IT IS INHERENTLY LIGHT WEIGHT, PARTICULARLY WHEN OPERATING PRESSURES ARE MODERATE.

HYDRAULIC: ARE EITHER LINEAR POSITION ACTUATORS OR A ROTARY VANE

CONFIGURATION.

HYDRAULIC ACTUATORS PROVIDE A LARGE AMOUNT OF POWER FOR A GIVEN

ACTUATOR.

THE HIGH POWER-TO-WEIGHT RATIO MAKES THE HYDRAULIC ACTUATOR AN

ATTRACTIVE CHOICE FOR MOVING MODERATE TO HIGH LOADS AT REASONABLE

SPEEDS AND MODERATE NOISE LEVEL.

HYDRAULIC MOTORS USUALLY PROVIDE A MORE EFFICIENT WAY OF ENERGY

TO ACHIEVE A BETTER PERFORMANCE, BUT THEY ARE EXPENSIVE AND

GENERALLY LESS ACCURATE.

INTELLIGENCE LEVEL

THE INTELLIGENT CONTROL ROBOT IS CAPABLE OF PERFOMING SOME OF THE FUNCTIONS

AND TASKS CARRIED OUT BY HUMAN BEINGS.

IT CAN DETECT CHANGES IN THE WORK ENVIRONMENT BY MEANS OF SENSORY PERCEPTION.

INTELLIGENT ROBOT IS EQUIPPED WITH A VARIETY OF SENSORS AND SENSOR APPARATUS PROVIDING

VISUAL (COMPUTER VISION) AND TACTILE (TOUCHING) CAPABILITIES TO RESPOND INSTANTLY TO

VARIABLE SITUATIONS.

MUCH LIKE HUMANS, THE ROBOT OBSERVES AND EVALUATES THE IMMEDIATE ENVIRONMENT BY

PERCEPTION AND PATTERN RECOGNITION.

SPECIFIC UTILITY OF

ROBOTS•Automobile

•Construction

•Entertainment

•Health care: hospitals, patient-

care, surgery , research, etc.

•Laboratories: science,

engineering , etc. •

•Manufacturing •Military:

demining, surveillance, attack,

etc.

•Mining, excavation, and

exploration •Transportation: air,

ground, rail, space,

Etc.

Entertainment

surgery

Industrial

applications:•Material handling

•Material transfer

•Machine loading

and/or unloading

•Spot welding

•Continuous arc

welding

•Spray coating

•Assembly

•Inspection

Human Robot

Advantages of Robots• Safety (human, machine and product)

• Can work in Hazardous environment

• Accuracy

• Repeatability

• No environmental comfort needed

• Continuous work without fatigue and boredom .

Disadvantages of Robots• Unemployment ( major problem)

• Economic problem ( salary)

• Dissatisfaction and resentment among workers

• Lack capability to respond in emergencies

• Lack of decision making power

• Limitations ( DOFs, Dexterity, sensors, real time response etc.)

• High initial cost

• Need for periphirals, training, and programming