ISE 370 Industrial Automation Instructor: Thomas Koon

1. ISE 370 Industrial AutomationInstructor: Thomas Koon Introduction To Robotics ISE 370

2. Introduction • The main purpose of this discussion is to provide a very basic understanding of “Robotics”, and how to apply that knowledge to our lab using the ADEPT “Robot” in Lab B-9 ISE 370

3. Topics of Discussion • Overview of Robotics • Classification and application of robotics • Robot components and subsystems • Kinematics and inverse transformation • Control of actuators in robotics systems • Robot sensory devices ISE 370

4. What is a Robot? "A reprogrammable, multifunctional manipulator designed to move material, parts, tools, or specialized devices through various programmed motions for the performance of a variety of tasks" Robot Institute of America, 1979 ISE 370

5. Robots: Hollywood Fiction vs. Real-World Fact ISE 370

6. Why Use Robots? • To save money? • To save people? ISE 370

7. Robot Concepts •Notion derives from 2 strands of thought: – Humanoids -- human-like – Automata -- self-moving things • “Robot” -- derives from Czech word robota – “Robota”: forced work or compulsory service • Term coined by Czech playwright Karel Capek – 1921 play “R.U.R” (Rossum’s Universal Robots”) ISE 370

8. Robot Concepts • Current notion of a Robot: – Programmable – Mechanically capable – Flexible • One working definition of robot: physical agent that generates “intelligent” connection between perception and action ISE 370

9. Advantages of Machines • Do not tire or grumble • Higher quality. • Repeatable performance • Stronger, faster, more accurate • More productive. • Work 24 hours each day • Immune to dangerous environment. ISE 370

10. Advantages of People: • Adaptable to problems and environments. • Wide range of sensory inputs, with pattern recognition. • Make decisions, set priorities and define goals. • Investigate new techniques. • Easy to program. ISE 370

11. Some Current State-of-the-Art Robots ISE 370

12. Robot Applications ISE 370

13. ROBOT KINEMATICS * Kinematics: is the science of motion. Kinematics is important in robots, used to model: • Mechanisms • Actuators • Sensors from Greek kinema = movement Forward kinematics is the transformation from joint space to Cartesian space Inverse kinematics solves for the joint angles given the desired position and orientation in Cartesian space ISE 370

14. Forward & Reverse Kinematics Forward Kinematics: For a given set of joint displacements, the end-effector position and orientation can be calculated. Inverse Kinematics: For a given set of end-effector position and orientation, joint displacements are computed. ISE 370

15. Rotational Transforms Rotation about a single axis: ISE 370

16. Joints & Links ISE 370

17. Link Frame Assignments Denavit-Hartenberg notation ISE 370

18. Joints in Zero Position ISE 370

19. Tool Frame to Base Multiplication of these matrices leads to the complete transformation ISE 370

20. Possible Robot Classifications • Power Source? • Classification by Level of Technology • Arm Configuration? • Classification by Controller • Application? ISE 370

21. Robotic Power Sources • Electric - Stepper motors (for economy) or servo motors (for precision) • Hydraulic – For Power • Pneumatic - For Speed • Vacuum – For pick and place operations ISE 370

22. Level of Technology 3 current levels of technology now used by robots: • Low technology robots are nonservo-controlled. 2. Medium technology robots use point to point controllers. 3. High technology robots use continuous-path controllers. ISE 370

23. Robotic Arm Configuration Five recognized arm configurations: • Rectangular (or Cartesian) Coordinates • Cylindrical Coordinates • SCARA • Polar Coordinates • Jointed Arm (or revolute-coordinates, articulate, or anthropomorphic). ISE 370

24. Cartesian Configuration (TTT) 3 Linear Axis ISE 370

25. Cylindrical Configuration(TTR, RTR, RRT) ISE 370

26. SCARA Configuration (RRT) ISE 370

27. SCARA Selective Compliant AssemblyRobot Arm In general, traditional SCARA’s are 4-axis robot arms, i.e., they can move to any X-Y-Z coordinate within their work envelope. There is a fourth axis of motion which is the wrist rotate (Theta-Z). ISE 370

28. Polar Configuration (RRT) ISE 370

29. Jointed arm/ Revolute Configuration (RRR) ISE 370

30. Classification by Controller Three basic types of robot controllers: • Limited Sequence • Point to Point • Continuous Path. ISE 370

31. Comparisons ISE 370

32. Robotics Applications ISE 370

33. Industrial Automation and Robots • While industrial robots and automated machines are usually treated as two separate topics, most industrial robots work in cooperation with other automated machines. ISE 370

34. Robot Communications LAN - is short for "local area network MAP - stands for "manufacturing automation protocol"; it is a communications standard developed for General Motors. TOP - is an acronym for "technical and office protocol," was developed for use in office automation by Boeing Computer Services ISE 370

35. Automated Machines Automated machines classes:hard automation and flexible automation machines. Hard automation deals with specialized machines designed for a specific operation or a narrow range of operations. Flexible automation deals with relatively general-purpose machines, such as the industrial robot. ISE 370

36. An Early Use • An early automated programmable industrial machine was the automatic loom, invented by Joseph Marie Jacauard in 1801. Jacquard showed how powerful it was by using 10,000 punched cards to weave a portrait of himself in black and white silk ISE 370

37. Terms • Computer-aided design (CAD) and computer-aided engineering (CAE) • Computer-Aided Manufacturing (CAM) • Computer-Aided Robotics (CAR) ISE 370

38. Robot Components Robots use arms, end effectors (grippers), drive mechanisms, sensors, controllers, gears and motors to perform the human-like functions necessary to perform their jobs ISE 370

39. Robot Components Arms: Robot arms come in all shapes and sizes. The arm is the part of the robot that positions the end-effector and sensors to do their pre-programmed business. • Many (but not all) resemble human arms, and have shoulders, elbows, wrists, even fingers. This gives the robot a lot of ways to position itself in its environment. Each joint is said to give the robot 1 degree of freedom. ISE 370

40. Robot Components Degrees of freedom: So, a simple robot arm with 3 degrees of freedom could move in 3 ways: up and down, left and right, forward and backward. Most working robots today have 6 degrees of freedom. Humans have many more degrees of freedom. Most jointed-arm robots in use today have 6 degrees of freedom ISE 370

41. Degrees of Freedom ISE 370

42. Links Robot links are considered to be rigid and inflexible. It is the link geometry which is used to determine the relative position of the kinematic coordinate frames. The position of a robots end-effector can be described in two ways, in Cartesian coordinates relative to its base frame and in joint coordinates. ISE 370

43. 2 Most Common Joints: Prismatic (linear) Revolute (Rotary) ISE 370

44. Types of Joint ISE 370

45. Robot Components AXIS OF ROTATION: X, Y, & Z, Are 3 of the degrees of freedom that robots perform. Most arms move according to Cartesian coordinates ISE 370

46. Robot Components End-effector The end-effector is the "hand" connected to the robot's arm. It is often different from a human hand - it could be a tool such as a gripper, a vacuum pump, tweezers, scalpel, blowtorch - just about anything that helps it do its job. Some robots can change end-effectors, and be reprogrammed for a different set of tasks. ISE 370

47. Robot DC Motors Parts of a 2-Pole DC Motor: • An armature or rotor • A commutator • Brushes • An axle • A field magnet • A DC power supply of some sort ISE 370

48. Stepper Motors Stepping motors can be viewed as electric motors without commutators.. All of the commutation must be handled externally by the motor controller. Most stepping motors can be stepped at audio frequencies, allowing them to spin quite quickly, and with an appropriate controller, they may be started and stopped "on a dime" at controlled orientations. ISE 370

49. Robotics Sensors & Controllers Sensors:collect all the information a robot needs to operate and interact with its environment. Controllers:interpret all the input from the sensors and decide how to act in response. ISE 370

50. Robotics Sensors & Controllers Sensors:control of a manipulator or industrial robot is based on the correct interpretation of sensory information. This information can be obtained either internally to the robot (for example, joint positions and motor torque) or externally using a wide range of sensors. ISE 370