ROBOTIKA IT-012276

Dr. Tb. Maulana Kusuma, SKom., MEngSc.

mkusuma@staff.gunadarma.ac.id

http://mkusuma.staff.gunadarma.ac.id

P1 | Dasar-dasar Robotika

What is a Robot?

Electro-mechanical device.

Performs Various tasks.

May be human controlled or automated.

It finds it’s uses in all aspects of our life.

Robota

The term robot originates from the Czech word, robota, meaning “compulsory labor (or slave)”

From the play R.U.R. (Rossum’s Universal Robots) by Czech play writer Karel Capek in 1921.

Three Laws of Robotics In 1942, Issac Asimov, An American science fiction

writer, introduced the word “robotics” in his short story

Law 1: A robot may not injure a human being, or, through inaction, allow a human being to come to harm

Law 2: A robot must obey the orders given it by human beings except where such orders would conflict with the First Law

Law 3: A robot must protect its own existence as long as such protection does not conflict with the First or Second Law

G. Walter’s Robot – The first Robot

1948, 1953

A wheeled machine with motors

Photocells

Two vacuum tubes

Moved toward light if moderate intensity

Avoided bright light

What defines a robot?

Sense – a robot has to take in information about its environment

Plan – a robot has to use that information to make a decision

Act – a robot needs moving parts to carry out commands

Robot Classes

Manipulators: robotic arms. These are most commonly found in industrial settings.

Mobile Robots: unmanned vehicles capable of locomotion.

Hybrid Robots: mobile robots with manipulators.

Manipulators Configuration

Polar

Cylinder

Cartesian

Joint-arm

Mobile Robots

Wheeled

– Holonomic

– Non-holonomic

Legged

– Humanoid

– Animaloid

Flying

Underwater

Industrial Robots

Material Handling

Manipulator

Assembly

Manipulator

Spot Welding Manipulator

•Material handling

•Material transfer

•Machine loading and/or unloading

•Spot welding

•Continuous arc welding

•Spray coating

•Assembly

•Inspection

What Robots can do?

Basic Parts of a Robot

Mechanical system

Power supply system

Actuators

Sensory devices for feedback

Sensor Data processing unit

Control system

Mechanical System

The most basic and important part of the robot.

It comprises of chassis, motors, wheels and their placement.

This system decides the locomotion of the robot.

Wheeled Locomotion Systems

Differential drive

Car type drive

Skid steer drive

Synchronous drive

Pivot drive

Differential Drive

This is the most commonly used form of locomotion system used in robots as it’s the simplest and easiest to implement.

It has free moving wheel(s) in the front accompanied with a left and right wheel. The two wheels are driven by different motors.

Differential Drive (Cont’d

Car Type Drive (Rack and Pinion)

It is characterized by a pair of driving wheels and a separate pair of steering wheels.

The translation and rotation are interlinked, hence this system faces severe path planning problem.

Car Type Drive (Cont’d)

Skid Steer Drive

A close relative of the differential drive system.

It is mostly used in tracked machines e.g. tanks. Also finds application in some four / six wheeled robots

The left and right wheels are driven independently.

Steering is accomplished by actuating each side at a different rate or in a different direction, causing the wheels or tracks to slip, or skid, on the ground.

Skid Steer Drive (Cont’d)

Synchronous Drive

As the name suggests, it uses synchronous rotation of its wheels to achieve motion & turns

It is made up of a system of motors. One set of which drive the wheels and the other set turns the wheels in a synchronous fashion

The two sets can be directly mechanically coupled as they always move in the same direction with same speed

Synchronous Drive (Cont’d)

Pivot Drive

• The most unique type of Locomotion system

• It is composed of a four wheeled chassis and a platform that can be raised or lowered

Pivot Drive (Cont’d)

The wheels are driven by a motor for translation motion in a straight line

For rotation one motor is needed to lower/raise the platform & another to rotate the chassis around the platform

This system can guarantee perfect straight line motion as well as accurate in – place turns to a desired heading

Power Supply System

Suitable power source is needed to run the robots.

Robots are most suitably powered by batteries.

The weight and energy capacity of the batteries may become the determinative factor of its performance.

Actuators

They convert the electrical energy into meaningful mechanical work

Mechanical output can be rotational or linear (straight line)

Motors provide rotational motion

Electromagnets provide linear motion

Motors are of various kinds

AC Motors : Not used much in robotics

Stepper Motors : For controlled rotation

DC Motors : Finds extensive general use

Servo Motors : DC motor with in built feedback & error compensation

Hydraulic Motor Stepper Motor

Pneumatic Motor Servo Motor

Pneumatic Cylinder

DC Motor

Sensors

Analogous to human sensory organs

– Eyes, ears, nose, tongue, skin

Sensors help the robot knowing its surroundings better

Improves its actions and decision making ability

Provides feedback control

Examples

Light Dependent Resistor

Thermistor

Flame Sensor (ie. UVTron)

IR Photo Sensor

Proximity Sensor (ultrasonic, IR)

Vision (camera)

Line Following Robot

A line follower is a robot capable of tracking a line drawn on a surface

Optical sensors capture the line position at the front end of the robot

The robot is steered to keep it always over the line

Optical Reflectors

TERIMA KASIH

Informasi Selengkapnya: UG Robotics Workshop (Bengkel Robot)

Kampus D, Gedung 3 Lantai 1 Utara

UG-VIBORG | Vision, Robotics and Real-time System Group

http://ugviborg.wordpress.com

Blog Komunitas Robotika UG:

http://robotika.blog.gunadarma.ac.id/