Robotics - bonabu.ac.iree.bonabu.ac.ir/uploads/31/CMS/user/file/103/Robotics/1-Robotics... · •“Introduction to Robotics, Analysis, Systems, Applications”, Saeed B. Niku, Prentice

RoboticsWinter 1393

Bonab University

Robotics - Course Information

Department of Electrical EngineeringInstructor: Fariborz Rahimi

Lectures: 3-5pm (Sat*), 3-5pm (Sun)

Prerequisites/Useful courses: Linear Control

Evaluation:

• In-Class participation: 20%

• Midterm 20%

• Final Exam 60%

References:

• “Introduction to Autonomous Mobile Robots”, R. Siegwart, Illah R. Nourbakhsh, MIT, 2004

• “Introduction to Robotics, Analysis, Systems, Applications”, Saeed B. Niku, Prentice Hall, 2001

• “Mobile Robotics – A Practical Introduction”, U. Nehmzow, 2° Ed., 2003

• [1] 1390 ,علیرضا رضایی ,”مقدمه ای بر روباتهای سیار خودکار “

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Robotics – Course Contents & Summary

• IntroductionEvolution-History, Applications, Wheeled/Legged vehicles, Manipulator arms, Robot subsystems

• Robot manipulators, Mobile robots (& mobile manipulators), Modular robots• Kinematics (Forward & inverse), path planning• Introduction to Mobile Robotics [1-1]

• Locomotion [1-2]• Legged-wheeled, key issues

• Mobile Robot Kinematics [1-3]

• Sensors & Interfacing (Perception [1-4])Limit switches (Mechanical-Optical), Hall-sensors, Proximity sensors, Potentiometers, Position encoders, Tachogenerators, Strain gauges and force sensors, Instrumentation amplifiers, Accelerometers, Rangers (ultrasonic-infrared), Optical reflective and light sensors, Linear optical sensors, 2-D vision systems

• ActuatorsSolenoids, DC motors, MOSFET drivers, H-Bridges and pulse width modulation, Brushless DC motors, Stepper motors, R/C servo motors, Gear trains, Pneumatic actuators, Hydraulic actuators, Shape changing

• Mobile robot Localizations [1-5]• Localize v.s. Programmed navigation, Maps

• Planning and Navigation [1-6]• Path planning, Obstacle avoidance

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Introduction: Multidisciplinary

• Robotics engineering encompasses:• Physics• Mathematics• Electrical Engineering• Mechanical Engineering• Computer Sciences/Engineering• Instrumentation and Control• Artificial Intelligence• Communication

• Should robots look like humans?“anthropomorphic or humanoid robots”.• Need to be intelligent - link to “Artificial Intelligence (AI)” • Need for humans to create machines similar to them

No they don’t, but they make use of:

• Strong & precise articulated arms to accomplish tasks that were

performed by humans – “articulated robots”, or “manipulators”

• Use of mobility to reposition the robot from one location to another,

“mobile robots”. This can be done by locomotion like humans (“legged robots”),

but most likely it will use other means such as wheels (“wheeled robots”).

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Introduction

Introduction: Definition (from: Dan O. Popa)

• According to the Robotics Industries Association (RIA): “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 (1985)”.

• This definition underscored the re-programmability of robots, but it also just deals with manipulators and excludes mobile robots.

• Close relationship with the concept of “automation”, the discipline that implements principles of control in specialized hardware. Three levels of implementation:• Rigid automation – factory context oriented to the mass manufacturing of products of the

same type. Uses fixed operational sequences that cannot be altered.

• Programmable automation – factory context oriented to low-medium batches of different types of products. A programmable system allows for changing of manufacturing sequences.

• Flexible automation – evolution of programmable automation by allowing the quick reconfiguration and reprogramming of the sequence of operation.

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Introduction

Introduction: Definition

• According to the Japanese Industrial Robot Association (JIRA), robots can be classified as follows:

• Class 1: manual handling device – a device with several DOF’s actuated by the operator.

• Class 2: fixed sequence robot – similar to fixed automation.

• Class 3: variable sequence robot – similar to programmable automation.

• Class 4: playback robot – the human performs tasks manually to teach the robot what trajectories to follow.

• Class 5: numerical control robot – the operator provides the robot with the sequence of tasks to follow rather than teach it.

• Class 6: intelligent robot – a robot with the means to understand its environment, and the ability to successfully complete a task despite changes in the surrounding conditions where it is performed.

• Another definition describes robotics as the intelligent connection between perception and action (Brady 1985). This is an overly inclusive definition.

• Yet another definition, which focuses on mobile robots (Arkin 1998) is “A robot is a machine able to extract information from its environment, and use this knowledge to move safely, in a meaningful and purposive manner”.

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Introduction

Introduction - Evolution and History

• Robotics was first introduced into our vocabulary by Czech playwright Karel Capek in his 1920’s play Rossum’s Universal Robots.

• The word “robota” in Czech means simply work. Robots as machines that resemble people, work tirelessly, and revolt against their creators.

• The same myth/concept is found in many books/movies today:• “Terminator”, “Star-Wars” series.

• Mary Shelley’s 1818 Frankenstein.• Frankenstein & The Borg are examples of “cybernetic organisms”.

• Cybernetics is a discipline that was created in the late 1940’s by Norbert Wiener, combining feedback control theory, information sciences and biology to try to explain the common principles of control and communications in both animals and machines.

• “Behavioral robotics”: organisms as machines interacting with their environment according to behavioral models.

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Introduction

Introduction - Evolution and History

• 1947-1949 – first electric and hydraulic teleoperators are developed by General Electric and General Mills. Force feedback is added to prevent the crushing of glass containers during manipulation.

• 1949 - CNC machine tools for accurate milling of aircraft parts are introduced.

• 1953 – W. Grey Walter applies cybernetics principles to a robotic design called “machine speculatrix”, which became a robotic tortoise. The simple principles involved were:• Simple is better. Simple reflexes are the basis of robot behavior.

• Exploration or speculation: the system never remains still except when recharging. Constant motion is needed to keep it from being trapped.

• Attraction: the system is motivated to move towards objects or light.

• Aversion: the system moves away from certain objects, such as obstacles.

• Discernment: the system can distinguish between productive and unproductive behavior, adapting itself to the situation.

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Introduction

Introduction - Evolution and History (Walter Grey's tortoise)

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Introduction

It had:

• a light sensor,

• touch sensor,

• propulsion motor,

• steering motor,

• a two vacuum tube

analog computer

Introduction - Evolution and History

• 1954 – George Devol replaced the slave manipulator in a teleoperator with the programmability of the CNC controller, thus creating the first “industrial robot”, called the “Programmable Article Transfer Device”.

• 1955 – The Darmouth Summer Research Conference marks the birth of AI. Marvin Minsky, from the AI lab at MIT defines an intelligent machine as one that would tend to “build up within itself an abstract model of the environment in which it is placed. If it were given a problem, it could first explore solutions within the internal abstract model of the environment and then attempt external experiments”. This approach dominated robotics research for the next 30 years.

• 1956 - Joseph Engleberger, a Columbia physics student buys the rights to Devol’s robot and founds the Unimation Company.

• 1961 – The first Unimate robot is installed in a Trenton, NJ General Motors plant to tend a die casting machine. The key was the reprogrammability and retooling of the machine to perform different tasks. The Unimate robot was an innovative mechanical design based on a multi-degree of freedom cantilever beam. The beam flexibility presented challenges for control. Hydraulic actuation was eventually used to alleviate precision problems.

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Introduction

Introduction - Evolution and History _ Unimate Robot

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Introduction

Unimate GE

Introduction: Manipulators

• Industrial manipulators were born after WWII out of earlier technologies:

• Teleoperators.

Teleoperators, or remotely controlled mechanical manipulator, were developed at first by Argonne and Oak Ridge National Labs to handle radioactive materials. These devices are also called “master-slave”, and consisted of a “slave” arm being guided through mechanical links to mimic the motion of a “master” arm that is operated by the user. Eventually, the mechanical links were replaced by electrical or hydraulic links.

• Numerically controlled milling machines (CNC).

CNC machines were needed because of machining needs for very complex and accurate shapes, in particular aircraft parts.

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Introduction

Introduction: Mobile Robots

• Mobile robots were born out of “unmanned vehicles”, which also appear in WWII (for example an unmanned plane dropped the atomic bomb at Nagasaki).

• Unmanned Aerial Vehicles (UAV), Underwater Vehicles (UUV) and Ground Vehicles (UGV).

• Because tethered mobile vehicles could not move very far, and radiocommunications were limited, an approach to mobile robots is to endow them with the necessary control and decision capability -“autonomy”

• Autonomous Underwater/Ground/Aerial Vehicles (AUV/AGV/AAV).

• We do not think of a remotely controlled toy as a mobile robot, suggesting that one of the fundamental aspects of mobile robotics is the capacity for autonomous operation.

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Introduction

Introduction to Mobile Robotics (Chapter-1)

• Manipulators (robot arms) = $2 billion industry

• Manipulator = bolted down + high speed/accuracy (repetitive jobs):

• Yet, manipulators suffer from a fundamental disadvantage: lack of mobility

• Mobile robot = travelling throughout the manufacturing plant

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Introduction

Spot welding Packaging chocolate

Introduction to Mobile Robotics

• Hostile environments (Mars) more

unusual locomotion mechanisms

• Even on earth dangerous/inhospitable environments teleoperated systems

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Introduction

Pathfinder

missions to

Mars, 1997

1st application driven

walking robot

Airduct inspection

robotDesigned to explore

ChernobylAUV dives beneath the

Arctic ice

Introduction to Mobile Robotics

• Other commercial robots rather share space with humans

• Another example of AGV (Autonomous Guided Vehicle):• Deliver parts between various assembly stations

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Introduction

Tour guide robot, Swiss

Exhib. (Robox)

SwissLog 100 is guided

by an electric wire

installed in the floor

Helpmate is used

in hospitals for

transportation

tasks

Introduction to Mobile Robotics

• Industrial and residential size cleaning robots:

• Research oriented robots for laboratory• Cognition, localization, navigation

• Wide range of size and terrain capabilities

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Introduction

-BR700 (left) Germany, uses sophisticated

sonar system and gyros

-RC3000 (right) optical sensors measure

degree of pollution of the aspirated air

Pioneer, with a gripper/camera

B21 is used for

Navigation research

Strong processing (3

intel processors)

Introduction to Mobile Robotics (Lab-robots)

• Research and education:

• Robotics: broad range of applications, but for all of them:

• A successful mobile roboticist needs:• Mechanisms and kinematics and control Locomotion

• Signal analysis and computer vision robust perception

• Computer algorithms, information theory, probability, & AI Localization & Navigation

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Introduction

-Khepera, 60mm diameter

Alice (very small),

2x2x2 cm

~ 8 hours of autonomy

IR distance sensors

Tactile whiskers

Control scheme for mobile robots

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Introduction

Main bodies of knowledge associated

with mobile robotics

Book provides an introduction to all

aspects

Focus:

• not on robotics in general

• nor on mobile robot applications

• rather on mobility itself

Techniques and technologies that

enable robust mobility