L1 - Introduction to Robotics V1

Introduction to Robotics

Originally prepared by: Prof Engr Dr Ishkandar BaharinHead of Campus & Dean

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Robotics History350 B.CThe Greek mathematician, Archytas builds a mechanical bird named "the Pigeon" that is propelled by steam.

322 B.C.The Greek philosopher Aristotle writes;“If every tool, when ordered, or even of its own accord, could dothe work that befits it... then there would be no need either ofapprentices for the master workers or of slaves for the lords.”...hinting how nice it would be to have a few robots around.

200 B.C.The Greek inventor and physicist Ctesibus of Alexandria designs water clocks that have movable figures on them.

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Robotics History1495Leonardo Da Vinci designs a mechanical device that looks like an armored knight. The mechanisms inside "Leonardo's robot" are designed to make the knight move as if there was a real person inside.

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Robotics History

Leonardo’s Robot

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Robotics History

1738Jacques de Vaucanson begins building automata. The first one was the flute player that could play twelve songs.

1770Swiss clock maker and inventor of the modern wristwatch Pierre Jaquet-Droz start making automata for European royalty. He create three doll, one can write, another plays music, and the third draws pictures.

1801Joseph Jacquard builds an automated loom that is controlled with punched cards.

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Robotics History

Joseph Jacquard’s Automated Loom

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Robotics History

1898Nikola Tesla builds and demonstrates a remote controlled robot boat.

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Robotics History1921Czech writer Karel Capek introduced the word "Robot" in his play "R.U.R" (Rossuum's Universal Robots). "Robot" in Czech comes from the word "robota", meaning "compulsory labor“.

1940Issac Asimov produces a series of short stories about robots starting with "A Strange Playfellow" (later renamed "Robbie") for Super Science Stories magazine. The story is about a robot and its affection for a child that it is bound to protect. Over the next 10 years he produces more stories about robots that are eventually recompiled into the volume "I, Robot" in 1950. IssacAsimov's most important contribution to the history of the robot is the creation of his “Three Laws of Robotics”.

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Robotics HistoryThree Laws of Robotics:

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

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

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

Asimov later adds a "zeroth law" to the list:Zeroth law: A robot may not injure humanity, or, through

inaction, allow humanity to come to harm.

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The term “robot”• Karel Capek’s 1921 play RUR (Rossum’s Universal Robots)

– It is (most likely) a combination of “rabota” (obligatory work) and “robotnik” (serf)

• Most real-world robots today do perform such “obligatory work” in highly controlled environments– Factory automation (car assembly)

• But that is not what robotics research about; the trends and the future look much more interesting

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1946George Devol patents a playback device for controlling machines.1961Heinrich Ernst develops the MH-1, a computer operated mechanical hand at MIT.1961Unimate, the company of Joseph Engleberger and George Devoe, built the first industrial robot, the PUMA (Programmable Universal Manipulator Arm).1966The Stanford Research Institute creates Shakey the first mobile robot to know and react to its own actions.

Robotics HistoryU

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Robotics History

SRI ShakeyUnimate PUMA

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Robotics History1969Victor Scheinman creates the Stanford Arm. The arm's design becomes a standard and is still influencing the design of robot arms today.

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Robotics History1976Shigeo Hirose designs the Soft Gripper at the Tokyo Institute of Technology. It is designed to wrap around an object in snake like fashion.1981Takeo Kanade builds the direct drive arm. It is the first to have motors installed directly into the joints of the arm. This change makes it faster and much more accurate than previous robotic arms.1989A walking robot named Genghis is unveiled by the Mobile Robots Group at MIT.

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Robotics History1993Dante an 8-legged walking robot developed at Carnegie Mellon University descends into Mt. Erebrus, Antarctica. Its mission is to collect data from a harsh environment similar to what we might find on another planet.

1994Dante II, a more robust version of Dante I, descends into the crater of Alaskan volcano Mt. Spurr. The mission is considered a success.

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1996Honda debuts the P3.

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Robotics History1997The Pathfinder Mission lands on Mars

1999SONY releases the AIBO robotic pet.U

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2000Honda debuts new humanoid robot ASIMO.

Robotics HistoryU

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...1921 242121502020

Karl Capek

Dalek

1950

I, Robot

Where would these RHF robots go?

Hal 9000 with Arthur C. Clarke’s reflection

Robot TimelineU

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...1951

Tortoise “Elsie”

http://www.frc.ri.cmu.edu/~hpm/project.archive/robot.papers/2000/revo.slides/1950.html

Grey Walter http://www.epub.org.br/cm/n09/historia/documentos_i.htm

Robot TimelineU

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Shakey

Nils Nilsson @ Stanford Research Inst.

......1968

first “general-purpose” mobile platform

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Stanford Cart

Hans Moravec @ SAIL

......1976

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“functional” task decomposition

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Hybrid systems

......1995

Polly Navlab & ALVINN

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An assortment of robots…U

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Anthropomorphic RobotsU

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Animal-like RobotsU

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Humanoid Robots

Robonaut (NASA) Sony Dream Robot

Asimo (Honda)

DB (ATR)

QRIO

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Robots: Alternative Terms• UAV

– unmanned aerial vehicle• UGV (rover)

– unmanned ground vehicle• UUV

– unmanned undersea vehicle

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Autonomous Solutions Inc.

Mobius:Mobius is an easy to use software interface for controlling and monitoring multiple unmanned vehicles using the JAUS protocol.

It includes a robust feature set developed over the last severalyears to speed productivity and meet the needs of our customers.

JAGUAR - Multiple-Use Utility Vehicle:JAGUAR is a rugged, autonomous platform just waiting to take your orders. Built around the Bobcat Toolcat 5600 utility vehicle, JAGUAR can take advantage of all the stock attachments, plus custom additions such as robotic manipulators, mine flails, and the Dynamic Cone Penetrometer (DCP). Coupled with the physical capabilities is a full electronic sensor package that enables a completely autonomous deployment out of the box and ready to go.

U.V.I.S. - Under-Vehicle Inspection SystemUVIS is a specially-designed robot built to inspect the underside of vehicles at police and military checkpoints and in parking lots. It provides a significantly safer method for checking vehicles for car bombs and other contraband by allowing soldiers and other security personnel to remain a safe distance from the vehicles in question.

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P.G.A.P. - Proving Grounds Automation Package:P.G.A.P. combines an easy to use software suite (Mobius) and robust hardware and electronics with quality services and support to provide a rugged and reliable automated test machine; one that doesn't get tired, complain, or ask for a raise.

SCORPIONM.U.R.V. - Multi-Use Robotic Vehicle:Scorpian is ruggedly-built for hazardous environments and can be operated remotely, allowing it to go places no manned vehicle could safely go. Scorpion has ample lifting capacity and with the diesel powerplant has abundant power and runtime. The base platform can be easily serviced through a worldwide dealer network. Scorpian can be outfitted with a variety of off-the-shelf attachments to meet any need.

Unmanned Target VehiclesAutonomous Solutions Inc. can create a custom unmanned target vehicle for you. We are able to convert any off-the-shelf commercial vehicles and implement them with autonomous or teleoperational control. This type of vehicle is useful for weapons systems development, live battlefield-type training and testing, and many other operations.

Autonomous Solutions Inc.U

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NaviGator

The NaviGator is a medium-sized autonomy testbed that provides the core hardware necessary for research and development of UGV technologies. This vehicle is based on a John Deere Gator platform that has been retrofit with “smart” Animatics SmartMotors® on the steering, throttle, and brake systems. (Transmission actuation is optional). These motors are linked with an on-board electro-mechanical power and safety system. In addition, the system includes an independent 36VDC power system (including charger and shore power operation) and can optionally include conditioned AC and DC power supplies. When combined with one of the above software packages, the NaviGatorprovides an out-of-the-box solution for advanced UGV research and development.

Please contact us if you are interested in adapting the basic technology provided in the NaviGator to your vehicle platform.

Applied Perception Inc.U

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Schilling Sub Atlantic Robots

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What is a Robot?• In the past

– A clever mechanical device – automaton• Robotics Industry Association, 1985

– “A re-programmable, multi-functional manipulator designed to move material, parts, tools, or specialized devices […] for the performance of various tasks”

• What does this definition missing?– Notions of thought, reasoning, problem solving, emotion,

consciousness

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A Robot is…• … a machine able to extract information from its

environment and use knowledge about its world to act safely in a meaningful and purposeful manner (Ron Arkin, 1998)

• … an autonomous system which exists in the physical world, can sense its environment and can act on it to achieve some goals

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What is Robotics?

• Robotics is the study of robots, autonomous embodied systems interacting with the physical world

• Robotics addresses perception, interaction and action, in the physical world

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Synthetic field

Robotics

• Architecture

• Mapping

• Sensing and Motion

• Cooperative Robotics

• Visual Control

• Entertainment• Planning / Modeling • Robot Learning

• Biology

• Neuroscience

• Cognitive Science

• Mechanical Eng.

• Electrical Eng.

• Control

• CS & AI

• Vision, HCI

• Software Dev.

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A Brief History of Robotics• Early work at end of WWII for handling radioactive

materials: Teleoperation.• Computer numerically controlled machine tools for low-

volume, high-performance AC parts• Unimation Inc.: built first robot in a GM plant. The machine

is programmable.• Robots were then improved with sensing: force sensing,

rudimentary vision.

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Robot: An electromechanical device with multiple degrees-of-freedom (DOF) that is programmable to accomplish a variety of tasks.

Robotics Terminology

Industrial robot:The Robotics Industries Association (RIA) defines robot in the following way:

“An industrial robot is a programmable, multi-functional manipulator designed to move materials, parts, tools, or special devices through variable programmed motions for the performance of a variety of tasks”

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Robotics: The science of robots. Humans working in this area are called roboticists.

Robotics TerminologyU

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A Brief History of Industrial Robotics…

• Two famous robots:– Puma. (Programmable Universal Machine for Assembly).

‘78.– SCARA. (Selective Compliant Articulated Robot

Assembly). ‘79.• In the ‘80 efforts to improve performance: feedback control +

redesign. Research dedicated to basic topics. Arms got flexible.

• ‘90: modifiable robots for assembly. Mobile autonomous robots. Vision controlled robots. Walking robots.

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Other Industrial Robot ExamplesU

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Industrial Robot Production Trends

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Production Trends

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Production Trends

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DOF degrees-of-freedom: the number of independent motions a device can make. (Also called mobility)

five degrees of freedom

Robotics TerminologyU

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Manipulator: Electromechanical device capable ofinteracting with its environment.

Anthropomorphic: Like human beings.

ROBONAUT (ROBOtic astroNAUT), an anthropomorphic robot with two arms, two hands, a head, a torso, and a stabilizing leg.

Robotics TerminologyU

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End-effector: The tool, gripper, or other device mounted at the end of a manipulator, for accomplishing useful tasks.

Robotics TerminologyU

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Workspace: The volume in space that a robot’s end-effector can reach, both in position and orientation.

A cylindrical robots’ half workspace

Robotics TerminologyU

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Position: The translational (straight-line) location of something.

Orientation: The rotational (angle) location of something. Arobot’s orientation is measured by roll, pitch, and yawangles.

Link: A rigid piece of material connecting joints in a robot.

Joint: The device which allows relative motion between two links in a robot.

A robot joint

Robotics TerminologyU

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Kinematics: The study of motion without regard to forces.

Dynamics: The study of motion with regard to forces.

Actuator: Provides force for robot motion.

Sensor: Reads variables in robot motion for use in control.

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Speed•The amount of distance per unit time at which the robot can move, usually specified in inches per second or meters per second.•The speed is usually specified at a specific load orassuming that the robot is carrying a fixed weight. •Actual speed may vary depending upon the weight carried by the robot.

Load Bearing Capacity•The maximum weight-carrying capacity of the robot. •Robots that carry large weights, but must still be preciseare expensive.

Robotics TerminologyU

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Accuracy•The ability of a robot to go to the specified position without making a mistake. •It is impossible to position a machine exactly. •Accuracy is therefore defined as the ability of the robot to position itself to the desired location with the minimal error (usually 25 µm).

Repeatability•The ability of a robot to repeatedly position itself when asked to perform a task multiple times. •Accuracy is an absolute concept, repeatability is relative.•A robot that is repeatable may not be very accurate, visa versa.

Robotics TerminologyU

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Robotics TerminologyU

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Components of Industrial Robots

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Power Sources for Robots

• An important element of a robot is the drive system. The drive system supplies the power, which enable the robot to move.

• The dynamic performance of a robot mainly depends on the type of power source.

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There are basically three types of power sources for robots:

1. Hydraulic drive• Provide fast movements• Preferred for moving heavy parts • Preferred to be used in explosive

environments• Occupy large space area• There is a danger of oil leak to the shop floor

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2. Electric drive• Slower movement compare to the hydraulic

robots• Good for small and medium size robots• Better positioning accuracy and repeatability• stepper motor drive: open loop control• DC motor drive: closed loop control• Cleaner environment• The most used type of drive in industry

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3. Pneumatic drive• Preferred for smaller robots• Less expensive than electric or hydraulic robots • Suitable for relatively less degrees of freedom

design• Suitable for simple pick and place application• Relatively cheaper

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Robotic Sensors

• Sensors provide feedback to the control systems and give the robots more flexibility.

• Sensors such as visual sensors are useful in the building of more accurate and intelligent robots.

• The sensors can be classified as follows:

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1. Position sensors:Position sensors are used to monitor the position of joints. Information about the position is fed back to the control systems that are used to determine the accuracy of positioning.

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2. Range sensors:Range sensors measure distances from a reference point to other points of importance. Range sensing is accomplished by means of television cameras or sonar transmitters and receivers.

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3. Velocity Sensors:They are used to estimate the speed with which a manipulator is moved. The velocity is an important part of the dynamic performance of the manipulator. The DC tachometer is one of the most commonly used devices for feedback of velocity information. The tachometer, which is essentially a DC generator, provides an output voltage proportional to the angular velocity of the armature. This information is fed back to the controls for proper regulation of the motion.

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4. Proximity Sensors:They are used to sense and indicate the presence of an object within a specified distance without any physical contact. This helps prevent accidents and damage to the robot.– infra red sensors– acoustic sensors– touch sensors– force sensors – tactile sensors for more accurate data on the position

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The Hand of a Robot: End-Effector

The end-effector (commonly known as robot hand) mounted on the wrist enables the robot to perform specified tasks. Various types of end-effectors are designed for the same robot to make it more flexible and versatile. End-effectors are categorized into two major types: grippersand tools.

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The Hand of a Robot: End-Effector

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The Hand of a Robot: End-Effector

Grippers are generally used to grasp and hold an object and place it at a desired location. – mechanical grippers– vacuum or suction cups– magnetic grippers– adhesive grippers– hooks, scoops, and so forth

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The Hand of a Robot: End-Effector

At times, a robot is required to manipulate a tool to perform an operation on a workpiece. In such applications the end-effector is a tool itself– spot-welding tools– arc-welding tools– spray-painting nozzles– rotating spindles for drilling– rotating spindles for grinding

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Robot Movement and Precision

Speed of response and stability are two important characteristics of robot movement.

• Speed defines how quickly the robot arm moves from one point to another.

• Stability refers to robot motion with the least amount of oscillation. A good robot is one that is fast enough but at the same time has good stability.

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Robot Movement and Precision

Speed and stability are often conflicting goals. However, a good controlling system can be designed for the robot to facilitate a good trade-off between the two parameters.

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The precision of robot movement is defined by three basic features:

1. Spatial resolution: The spatial resolution of a robot is the smallest increment of movement into which the robot can divide its work volume.It depends on the system’s control resolution and the robot's mechanical inaccuracies.

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2. Accuracy: Accuracy can be defined as the ability of a robot to position its wrist end at a desired target point within its reach. In terms of control resolution, the accuracy can be defined as one-half of the control resolution. This definition of accuracy applies in the worst case when the target point is between two control points.The reason is that displacements smaller than one basic control resolution unit (BCRU) can be neither programmed nor measured and, on average, they account for one-half BCRU. U

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The accuracy of a robot is affected by many factors. For example, when the arm is fully stretched out, the mechanical inaccuracies tend to be larger because the loads tend to cause deflection.

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3. Repeatability: It is the ability of the robot to position the end effector to the previously positioned location.

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The Robotic Joints

A robot joint is a mechanism that permits relative movement between parts of a robot arm. The joints of a robot are designed to enable the robot to move its end-effector along a path from one position to another as desired.

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The Robotic Joints

The basic movements required for a desired motion of most industrial robots are:

• 1. rotational movement: This enables the robot to place its arm in any direction on a horizontal plane.

• 2. Radial movement: This enables the robot to move its end-effector radially to reach distant points.

• 3. Vertical movement: This enables the robot to take its end-effector to different heights.

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The Robotic Joints

These degrees of freedom, independently or in combination with others, define the complete motion of the end-effector. These motions are accomplished by movements of individual joints of the robot arm. The joint movements are basically the same as relative motion of adjoining links. Depending on the nature of this relative motion, the joints are classified as prismatic or revolute.

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The Robotic Joints

• Prismatic joints (L) are also known as sliding as well as linear joints.

• They are called prismatic because the cross section of the joint is considered as a generalized prism. They permit links to move in a linear relationship.

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The Robotic Joints

Revolute joints permit only angular motion between links. Their variations include:– Rotational joint (R)– Twisting joint (T)– Revolving joint (V)

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The Robotic JointsU

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The Robotic Joints

In a prismatic joint, also known as a sliding or linear joint (L), the links are generally parallel to one

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The Robotic Joints

A rotational joint (R) is identified by its motion, rotation about an axis perpendicular to the adjoining links. Here, the lengths of adjoining links do not change but the relative position of the links with respect to one another changes as the rotation takes place.

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The Robotic Joints

A twisting joint (T) is also a rotational joint, where the rotation takes place about an axis that is parallel to both adjoining links.

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The Robotic Joints

A revolving joint (V) is another rotational joint, where the rotation takes place about an axis that is parallel to one of the adjoining links. Usually, the links are aligned perpendicular to one another at this kind of joint. The rotation involves revolution of one link about another.

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